I'm Larry Tollen and Team Leader of MyNCHomes. We specialize in assisting Buyers and Sellers throughout Carrboro, Cary, Chapel Hill, Durham, Hillsborough and Pittsboro, North Carolina. I've been buying and flipping homes from the time I was 18 years old and at 26, I got a real estate license which I never actively used other than to save on commission on the homes I was buying and selling. In 1991 I decided to move into real estate full time and have never looked back.
Buyer Side Brokering and First Time Homebuyers Specialist. I am SFR and e-PRO certified. I will diligently search for properties that meet your specific criteria. Once you find a property you want; I will analyze its true market value and show you how the neighborhood has trended over time.
Seller Representation. I am a master at Internet Marketing. I will guarantee that your home is given the most effective marketing possible, designed to give it maximum exposure to local, national and international Buyers.
Negotiations. I do not represent both Buyer and Seller in a single transaction; I am focused exclusively on doing wha'ts best for you. I have more than 25 years of experience in successfully negotiating real estate transactions; I know how to craft deals that work for my clients. I will track and communicate to you; throughout the entire process from start to finish. You will know at all times where we're at and what's being said so there are no surprises. My objective is a smooth transaction and closing.
Resource. I can offer personally vetted professional resources from Inspectors, Mortgage Lenders, Contractors, Tradesmen, etc. Long after you've purchased, I will be there for you.
2014 Best of Trulia Top Agent Award I was also very proud to be recently honored by Trulia and as the Featured Cover Agent on Top Agent Magazine.
2015 Featured Cover Agent in Top Agent Magazine - Read it here!
And, this is all only the beginning of what MyNCHomes provides to you. To learn much more, please visit our website at www.MyNCHomes.com .
My husband and I recently sold our home with Larry's help. We had an aggressive timeline and needed a reliable relator to promote our interests as we were planning to be out of state for the majority of the process. We could not have found a better person to assist us. Larry was knowledgable, professional, quick to respond, and helped make our move as smooth as possible. Our house sold within our timeframe for above asking price. We highly recommend Larry Tollen!
Larry Tollen is the best type of realtor. As a firs time homebuyer I had alot of questions and concerns about the process. I have had lots of friends who have been buying homes before me and so I asked them what type of realtor they had and decided that there are two types of realtors 1.) the type that helps you see the good things about the houses and 2.) the type who knows tons about construction, materials, and the possible drawbacks of each house and tells you all the critical information you can so that you can make the best decision for you. Larry is able to do both – but especially excels and looking deeply into the construction and materials of a house. He provided me with tons of information that I would not have known and helped me a avoid a few places that looked great but were concealing some flaws that would have made them a bad fit and that I would have never seen on my own. He was kind, caring, and amazingly in touch and communicative. He is someone you can trust and count on. I have already recommended him to friends and hope that everyone can have as positive a home buying experience as Larry was able to facilitate for me.
Larry Tollen recently helped my family to sell our place in Carrboro. With his breath of knowledge and skillset, we were able to get multiple offers to sell the property above our asking price. Larry was also our buyer's agent of the same property more than 10 years ago. We have to say from both experiences that he's a truly amazing buyer's agent and seller's agent.
Larry knows the ins and outs of the real estate market in the triangle area and NC. He works relentlessly for his clients and is always so responsive and honest that we will take his advice without any second guessing. In addition, Larry always keeps us in loop with every single step in the buying and selling process. He has done a great job with our negotiation. Based on the experience above, we truly think Larry is a first-rate real estate agent whom we would recommend without any reservations.
Larry is a first-rate buyer's agent. He's knowledgeable, responsive, professional, and a great communicator.
Larry helped us buy a home in Chapel Hill when we decided to move back to NC from out of state. Shopping from out of state in a tight market is tough, and Larry was extremely helpful. I flew in for 3 days and spent 2.5 of those days with Larry, looking at houses, negotiating an offer, and executing paperwork. I was glad to have his full attention during that time, and he helped me make the most of the time available.
The rest of the diligence and closing process went smoothly. Larry has extensive experience building and improving homes, which he puts to good use during both selecting and inspecting a home. He says his role is to help clients understand the condition of a home's major systems and leave the subjective, aesthetic matters up to his clients -- for us, that was a great fit.
We have already recommended Larry to two relatives shopping for homes in Chapel Hill, and I wouldn't hesitate to work with him again the next time I shop for a home here.
Larry helped us find our dream home in the Chapel Hill area. We were new to the process and the area, and Larry communicated everything we needed to know and helped us understand the process. Our home was for sale by owner, a situation we didn't quite understand. The seller ended up telling us that he accepted our offer over a higher one because he trusted that Larry would get it done quickly and efficiently. Larry also works with solid vendors and professionals in the area (home inspection, well/septic, maintenance, etc.) and the process from offer to close couldn't have been easier. His background in construction also helped us learn quite a bit as we toured homes. We'd definitely recommend working with Larry.
Larry did a fantastic job helping us buy our home. He is knowledgable, responsive, experienced and helped us greatly in the negotiation process. I would recommend Larry to anybody looking for real estate in the triangle area of NC.
My wife and I HIGHLY recommend our Realtor and friend Larry Tollen! I usually don't post many reviews, as I feel I get or have had the basic service from anyone or anything, like everyone else. This experience was not just like everything else! Larry went above and beyond for our family! We were selling our townhouse and also needed to find our dream home. Larry said "don't worry guys, I will take care of everything". We sold our place in just two days of being on the market, with 11 total offers! I was more than pleased with the whole process and felt like we were in the best hands possible! We are now in our dream home and couldn't be happier with Larry and all he has done for our family!
Larry helped me buy my first house on my own and then helped my husband and myself buy our first house together.
I wouldn't have used any other realtor. Larry's ridiculously responsive, genuinely attentive, has decades of experience under his belt and knows the ins and outs of houses. He's pragmatic, he works hard for you as a seller and as a buyer...and frankly, he's worth every penny.
It has been a pleasure to go through this experience twice with Larry and his team.
Larry was a great realtor to work with. He knew a tremendous amount about the area and was always just a phone call away. He was knowledgable about the entire process for first-time homebuyers like ourselves. Larry negotiated a good deal for us and even cut some of the closing costs.
My family recently relocated from New York City to Durham, NC, and Larry Tollen helped us throughout the process. I really can't recommend him highly enough. The experience was ideal and we are delighted with our new home. Larry combines a deep knowledge of the real estate environment down here (as well as home construction) with a strong sense of professionalism and integrity, as well as a robust network of resources for the home buyer and home owner. He quickly became our "go to" person for any questions we had related to our move, including referrals to a host of related services. We were particularly impressed with Larry's responsiveness. He very efficiently balanced a heavy load of clients during a busy season with our needs for information and questions about our house search. Larry is a calm and easygoing person, which was very reassuring during the occasionally stressful process of buying a home. His confidence and knowledge were always reassuring, and his proactive handling of the due diligence, legal, and financial aspects made everything that much easier for us. So, all in all, we will recommend Larry very highly to anyone who asks (and will likely take him up on his invitation to use him as a referral source for home services-related information!)?
Larry knows his stuff, and definitely works relentlessly on behalf of his buyers. Real Estate can sometime feel like a battle....and it is times like those, when you had better hope you have Larry on your side, and not against you.
Throughout the process, if I needed to talk, to strategize, or just vent, he was always available and willing to chat. If you had asked me at the time, I would have sworn we were his only customers, but I know for a fact that was not the case. Larry just somehow manages to stay on top of everything with ease.
Larry was absolutely great to work with. He was always quick to respond to my e-mails or phone calls, which is an absolute must-have for anyone I choose to work with. He has a great deal of experience not only with real estate transactions, but also with home building, so he was very handy to have in our corner when evaluating possible home purchases. In the end, my wife and I used Larry as our buyer's agent and couldn't have been happier with his services.
My husband and I recently worked with Larry to purchase our first home and we could not be more pleased with the outcome. Not only were we about to become first time homeowners, but also first time parents, so we were working against a budget and the countdown to the arrival of our son.
Larry has so much knowledge and understanding of the real estate market and as brand new shoppers this was so helpful to us. He was able to tell us things about a home we saw that we may not have noticed or thought to ask about and this helped us really see the whole picture and not just the price tag while we were out looking at homes.
Larry made himself available to us on the weekends so we could work within our work schedules and also made last minute changes to the lineup of homes we wanted to see if a house came on the market late the day before our scheduled outing.
In addition to being extremely knowledgeable, Larry was also a lot of fun to work with! We enjoyed our time with him and also felt comfortable and confident with any additional vendors he suggested (such as homeowners insurance agents, lenders etc.). We had hoped to be moved into our new home prior to our son joining our family and although we knew this was a tall order given the limited time we had (less than 4 months), with Larry's help we were moved into our home with time to spare.
Although we love our house, when/if we plan to move again we will definitely be giving Larry a call!
Larry Tollen is an excellent realtor and we wholeheartedly recommend his services as a real estate agent. Larry knows the local market and was able to show us homes in our price range throughout the Durham–Chapel Hill area. He suggested we look at new construction as it gave us virtually everything we wanted generally at a lower price point. We ended up taking that advice and just closed on our newly constructed house in mid-November. Larry was with us every step of the way; this was critical for us as we were out-of-state during the building process. He is diligent, knowledgeable and very easy to deal with. He responds to all enquiries promptly and in a thorough manner. Honestly, he exceeds expectations. Furthermore, he is professional; he neither smothers you in trite observations nor does he fail to listen to your preferences and requirements. He added genuine value to our real estate buying experience.
Larry is very knowledgeable and responsive. He's a strong negotiator and he made me and my wife extra confident during the process. His background as a contractor made him especially helpful during our purchase.
Read the good things everything everyone else wrote. It's true. Larry is great at his job. He helped me buy my first home. I went through the process and bought this house on my own, so it was extra important for me to work with someone who was thorough, patient, and honest.
My husband and I were comforted knowing that we were in such capable hands during our home building and buying process. Larry eloquently and effectively handled several mishaps on the part of the builder that occurred while our home was being built. Larry is an honest, dedicated realtor that shares his knowledge of critical aspects of the home and buying process with his buyers. He never pressured us to rush into any contract with him or the seller. We sincerely appreciate his expertise and highly recommend him to prospective buyers.
?My family recently relocated from New York City to Durham, NC, and Larry helped us throughout the process. I really can't recommend him highly enough. The experience was ideal and we are delighted with our new home. Larry combines a deep knowledge of the real estate environment down here (as well as home construction) with a strong sense of professionalism and integrity, as well as a robust network of resources for the home buyer and home owner. He quickly became our "go to" person for any questions we had related to our move, including referrals to a host of related services. We were particularly impressed with Larry's responsiveness. He very efficiently balanced a heavy load of clients during a busy season with our needs for information and questions about our house search. Larry is a calm and easygoing person, which was very reassuring during the occasionally stressful process of buying a home. His confidence and knowledge were always reassuring, and his proactive handling of the due diligence, legal, and financial aspects made everything that much easier for us. So, all in all, we will recommend Larry very highly to anyone who asks (and will likely take him up on his invitation to use him as a referral source for home services-related information!)?.
Larry was thoughtful and imaginative about what we were looking for, and often was able to anticipate both the limitations and the advantages of a space in relation to our vision. He has an eye for the possibilities of a space. He had from the outset a patient understanding that the search could take some time; we never felt the slightest pressure about time. He was flexible about scheduling. He is knowledgeable about building and repair: he can judge the life of a roof or an HVAC system or siding. He knows a lot about the way a house sits on a lot (he gave good notes on potential sources of flooding, the grading of the earth around the foundation, etc.). He is the king of email responsiveness: we always heard back from him within a few hours, often within a few minutes. He is very well connected and has helpful contact lists full of people who do not want to disappoint him (we used one of his recommended bankers, who very clearly works hard to remain high on Larry's list). I will recommend Larry to everyone I know and will call on him again the next time we're in the market.
Larry did a fantastic job assisting my wife and me with buying our first home! He was always very prompt in returning emails and answering questions. He was also a very effective negotiator when it came to ironing out the details of our transaction. We would absolutely use Larry again!
Larry is an ultimate professional who brings a discipline to the real estate selling/buying process. His negotiating skills and knowledge of the local "landscape" were invaluable and served to deliver a highly satisfying result. I strongly recommend him for both buying and selling a house in the area.
I know Larry for a few years. He helped me to buy a house and he helped me to sell a house when I had to move out of the area because of the family situation. The first of all Larry is very personable and amazing to work with! His knowledge of the market around the area is exceptional.His responsiveness is top-notch, and I felt like he was totally and completely selfless to make sure the house was looked after since I had move to a new area before the house was sold. He did an excellent job, the house was sold within a day of being on the market.
I highly recommend Larry to everybody and especially to a new buyers.
I would never work with another Realtor. Larry is exceptionally knowledgeable and communicative throughout the process. When I thought I might have to pull out of the deal due to my current lease situation, he came up with such a great alternative that my lender was envious, saying, "I wish I had thought of that!" We closed on time with very few hiccups. You will not regret hiring Larry as your Realtor!
Larry is very easy to get along with and he understands what the client is looking for. He is extremely well versed in his profession and he makes the process a fully informed experience.
As first time home buyers with a limited budget, we were in need of a Realtor who would be patient and willing to explain the process to us, and Larry met our needs and exceeded our expectations. Working with Larry was a pleasure, and his reassurances and suggestions were immensely valuable throughout this process. During viewings, Larry would point out all manner of things (while we were walking around doing the emotional assessment, he was busy looking for potential financial pitfalls: "Guys, I'd like you to come look at this..." was a phrase we heard often). He was good with giving guesstimates of the ages of things like the roof and HVAC system, and educating us about things like "just house settling cracks" and "signaling distress cracks" in the foundation.
When we decided on a house, Larry took care of EVERYTHING! He organized the inspections to be done all on one day, and the inspectors he set us up with were courteous and thorough. When someone else (the sellers, for instance) were taking too long to respond, Larry was quick to write a short note "just checking in" to make sure that the process didn't drag on. We were kept up to date on each communication Larry had with every other person we dealt with.
Larry Tollen has successfully been in the real estate business for more than two decades so he must be doing something right. We recently bought a home that he brokered for my wife and I. The transaction had been nothing less than exceptional. What made it exceptional was that we were purchasing the house while living in another state with few opportunities to be hands on.
We have owned several properties over the years and found the transaction process less than fun. Larry working extremely well with his excellent associate Andrew Palumbo has made our acquisition go extremely well. Larry absolutely knows real estate and communicates verbally and in writing clearly and understandably. He always has his client in mind and goes beyond what is usually required to make the transaction go smoothly as possible. We are glad we found him and you will be too.
Larry helped us buy a home in the Chapel Hill area. Our situation was unique in that we had specific requirements and we also were commuting to Chapel Hill from 450 miles away. Larry maximized the use of emails and telephone calls to make the long distance process much easier.
Furthermore, Larry's exceptional knowledge of home construction helped tremendously in that we were planning to perform major modifications to the home after our purchase.
Larry Tollen was a great broker to work with! Although I did not purchase the home that I was interested in, Larry worked very diligently to get information for me regarding the home buying process and the home itself. It was very communicative and made sure I understood each step of the home buying process which was good for me since I am a first-time home buyer.
Larry Tollen is truly great at what he does. He provides a wealth of knowledge for both buyers & sellers in the real estate market. He listens to clients & guides them to their best options based on both their needs & wants, providing insight & clarity along the way. A true professional, Larry makes what is a daunting task seem relatively easy. I trust his opinions in the world of real estate & look forward to the opportunity of working with him again.
As a first time homebuyer, I was pretty nervous about the whole process. Larry never pressured me to make any decisions; however, he worked more quickly than I could have asked for once I decided on a home. He is full of knowledge that extends farther than what I would expected with a broker. He gave me advice and held my hand through the whole process. I am extremely happy in my new home and have no regrets about any of the steps. Larry is a great guy, and I enjoyed working with him immensely.
Larry is a personable,sensitive and exceptional realtor and we would highly recommend him . Thank you Larry !
We are extremely pleased to have chosen Larry to help us buy our first home. We were a bit unsure at first about what exactly we wanted, but Larry was very accommodating and we soon found the perfect house for us. We appreciated that Larry did not hesitate to share his opinions about the houses we viewed. He seemed at all times to have our best interests in mind and wanted to make sure the house we bought is one we would be happy in for many years to come.
Once we found the house for us, Larry seemed to effortlessly guide us through to closing even though we were several states away. We felt very comfortable throughout the whole process and Larry has some great connections in the area that made thing go very smoothly.
Helped us sell our town home in Morrisville and buy a new home. I recommend him without reservation. He was an excellent source of support and his professional advice helped us through several tricky situations.
Larry is a gifted realtor. I have bought four houses in my lifetime, but I have never worked with a realtor who combines such a sharp an eye for value with such a thorough grasp of the buyer's aspirations. In addition, in my most recent transaction, Larry went out of his way to make every single step as painless as possible. I am deeply appreciative, and recommend Larry to anyone seeking a realtor in the Triangle.
I Have known Larry for almost ten years. He makes sure his clients gets the possible possible service in every transaction. He has superior communication skills and always keeps his clients up to date on their transactions.
Larry was referred to me by a lender that I had a relationship with. He was always very responsive and took the time to get to know what I was looking for. He only sent me listings that matched what I wanted, which saved a lot of time. After not finding anything I was happy with, I decided on new construction.
Larry went above and beyond once the sale was made and I signed the contract to build by showing up to the design center to give his opinion on what would be good to pick for resale purposes. He also stopped by the house several times to check in on it. His background in construction helped as he was able to point out red flags (both as we looked at used homes and through the new home build process).
I've already recommended Larry to some of my friends and clients looking to buy homes and will definitely be contacting him again for any future needs in the RDU area.
We wholeheartedly recommend Larry and the Home Team, as did an amazing job selling our homes and buying a new one. He came over a few months before we listed to give suggestions, talk about the market and prices, and get to know what was important to us. He was incredibly thorough and helpful at each and every stage. We listed and signed a contract above list price in less than 24 hours. That was exactly what we wanted (we had seen houses linger in our neighborhood the year before and that was a major concern so speed of sale was critical for us over pure price maximization). We are happily settled where we want to be with very little stress or disruption. With four small children, endless showings and open houses would have been impossible.
Although I could select for both in this review, Larry helped us navigate the contract, due diligence period and any repairs, and also purchase of our new home. I highly recommend Larry. He is an advocate for his clients and we enjoy the time we spend with him then and now. He has a wealth of information about the area, as well as excellent service providers for new projects or repairs/inspections. His marketing style and associated video were stellar (my husband works in marketing and was similarly impressed and pleased).
Truly no downsides for us either in the sale of our former homes or purchase of our new home. In our eyes, Larry is the only realtor to use.
We were out of state buyer's and Larry spent an entire week showing us homes. He was quick to realize what we wanted . Once we decided on the home we wanted, his negotiating skills were great!
We highly recommend working with Larry for buying or selling a home! He is, by far, the best realtor we have ever worked with!
We would recommend Larry without hesitation to anyone looking to sell their home. From our first meeting, his knowledge of the real estate business, the local area, and home building was evident. With his exceptional marketing skills and staging recommendations, our house was under contract at full asking price within two days of being on the market. Throughout the entire process, he was quick to respond to any emails or calls, and he always kept us in the loop. Our move was necessary because of health and resulting financial reasons, and Larry was understanding and honest about what he believed would be the best decision for us, even if it meant sacrificing a sale on his end. We appreciated his dedication and negotiation skills. We are so happy we decided to go with Larry when we sold our home, and we will contact him again if we decide to buy in the area.
Larry helped my husband and I both buy and sell our home in Durham, and I truly cannot say enough positive things about him.
On the buying side, Larry took me to view many homes, and he quickly grasped what my husband and I were looking for and found lots of great options in our price range. Additionally, Larry knew that we planned to live in the house for only three years (my grad school years), and he was knowledgeable and forthcoming with what he believed each house's resale potential would be. He was also very knowledgeable when it came to home maintenance and potential inspection issues.
When it came time to sell, Larry made the process seamless, despite the fact that we were out of state by the time the house got listed. Even from afar, it was clear that Larry worked hard to market the house, and we were under contract in less than three months. Just as when we bought the house, he was an excellent advocate during negotiations, and he walked us through every step of the closing process.
If you are looking for a real estate agent in the greater Durham/Chapel Hill area, I highly, highly recommend Larry. He is dedicated, professional, and an absolute pleasure to work with.


text:
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Statement upon City Planning's certification of a zoning change to eliminate the Special Garment Center District
New York City's Garment Center is the greatest concentration of fashion design and production on the planet. The lasting vitality of this industry was made possible 30 years ago by creation of a Special Garment Center District, which mandated a diversity of spaces to sustain the diverse users that make up the fashion ecosystem: the designers, pattern makers, cutters, sewers and pleaters; the sellers of textiles, buttons and supplies; the showrooms, factors and truckers; the schools whose graduates both launch their own lines and infuse new talent to continuously rejuvenate the industry; and even the restaurants and delis where manufacturers meet to swap information and favors.
The implementation of the Special District was driven by the incredible dedication, foresight and enlightened self-interest of industry stakeholders led by the International Ladies Garment Workers Union, the New York Skirt and Sportswear Association, and many of the owners of the showroom buildings. They foresaw that the proposed redevelopment of Times Square immediately to the north of the Garment Center would attract office development that would eventually displace the manufacturers and that displacement would undermine the productivity of designers and the very desirable showrooms, which paid more than other office users. This cascading effect would have led to the collapse of the entire ecosystem.
Thirty years later, despite an almost complete lack of enforcement, the ecosystem continues to innovate and create fashion and jobs that generate $11 billion in wages and 184,000 jobs. As garment production has dropped in the United States and technology has made existing workers more productive, the need for production space in proximity to designers, while still important, has decreased. There is a need to maintain some space for production but not as much as provided by the zoning. At the same time, the City cites a need for additional low-cost office space to house new, emerging sectors.
Pratt Center for Community Development has long advocated that the Special District zoning could be replaced with alternative strategies to preserve the diversity of spaces needed to sustain the ecosystem and that the best way to achieve this would be through the ownership of space by a nonprofit organization dedicated to strengthening the industry. The industry must control its own space to ensure its future.
Today's expected certification of zoning changes to eliminate the Special District and replace it with tax incentives for building owners to rent to manufacturers and, more importantly, a commitment by the City to fund the acquisition of space by a mission-driven nonprofit is perhaps the most significant milestone since the creation of the district itself. These actions represent smart, prescient moves in a long-term strategy to ensure that the fashion industry remains vibrant for decades to come.
There have been many missteps along the way and many, many details remain to be hammered out for the vision to be fulfilled. But in this moment, there is unique alignment among the industry, elected officials, and the residents of the surrounding community that makes me hopeful. Council Speaker Corey Johnson, Manhattan Borough President Gale Brewer, EDC President James Patchett and their staffs have spent a tremendous amount of time and energy to build a new foundation for the industry's continued vitality.
At the Board of Estimate hearing before the vote on the proposed Special Garment Center District in 1987, a woman from Community Board 4 in Manhattan testified that it was her job sewing that kept bread on her family's table during the Depression. The fashion industry is one of the great forces that shaped the city's history and continues to be part of the constellation of industries that drive New York's future as a global center for creativity and innovation. Thousands of talented aspiring designers move to New York City each year to be part of this future.
We at the Pratt Center are committed to working with all the industry stakeholders – the manufacturers, the workers, the designers present and future and the residents of the surrounding communities – and elected officials to ensuring the fashion industry remains an exciting, vibrant and inspiring part of the city for generations to come.
Click here to learn more about Pratt Center's work in the Garment Center
Click below to download the statement as a PDF
Industrial Businesses in North Brooklyn Under Threat
Under the Hood: A look into New York City's Auto Repair Industry
What Makes the City Run: Preserving space for critical economic activities
Those who say 'wait:' What Industry City's opponents want
If Your City Wants Equitable Job Growth, It Has to Zone for It
New York's Famous Smoked Salmon Maker Wants a Big Brooklyn Expansion
Keeping Jobs in Fashion
Help Build a More Sustainable & Equitable NY!
© 2019 Pratt Center for Community Development

redpajama_set_name: RedPajamaCommonCrawl


text:
package client

import (
	"crypto/tls"
	"crypto/x509"
	"io/ioutil"
)

func (host *Host) getTLSConfig() (*tls.Config, error) {
	var tlsConfig tls.Config

	if !host.TLS {
		return nil, nil
	}

	tlsConfig.InsecureSkipVerify = !host.TLSVerify

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		certPool := x509.NewCertPool()
		file, err := ioutil.ReadFile(host.TLSCaCert)
		if err != nil {
			return nil, err
		}
		certPool.AppendCertsFromPEM(file)
		tlsConfig.RootCAs = certPool
	}

	cert, err := tls.LoadX509KeyPair(host.TLSCert, host.TLSKey)
	if err != nil {
		return nil, err
	}
	tlsConfig.Certificates = []tls.Certificate{cert}
	tlsConfig.MinVersion = tls.VersionTLS10

	return &tlsConfig, nil
}

redpajama_set_name: RedPajamaGithub


New Apple Multitouch ipod nano 6th generation 2010 (8GB, green). The most-talked about annual fall media event of Apple is over. The corporate-giant Apple discussed many important things on this most-talked about even that was held on Wednesday. Now it is over, but the debate continues to rage in the industry about its importance.
The bundle includes the Xbox 360 250GB Console. It also has the Kinect Sensor for the Xbox 360 so it will pick up on all your game moves. The bundle features the Adventures Game that is rated "E" for everyone. So be ready to go on an exciting adventure with your family and friends. The Xbox 360 has a black wireless controller and Xbox 360 Headset. It also comes with the Xbox 360 Composite a/v cable. This new and fun way to play games without the need for controllers is a hot ticket item so be sure to pre-order yours today so you get it when it releases.
The mobile phones are the basic necessity in day to day life. Apart from being a perfect communication tool, a gadget also serves all the entertainment purposes. There are many smartphone manufacturing companies like Nokia, BlackBerry, Samsung, LG etc. HTC is another name in the wide list of handset manufacturing brands. This company is quite popular for bringing latest gadgets packed with advanced technologies. This time HTC came into arena with fully featured mobile phone named as HTC Desire HD. This awesome handset is wrapped with a set of mind-blowing features.


The Graduate Diploma in Business Administration meets the need of those wanting to gain a qualification which provides a firm grounding in business administration and a basis for further academic study.
This course focuses on the functional areas of management and administration within an organisation and how those disciplines integrate at the operational level, linking with the overall corporate strategy to achieve short, medium and long term objectives.
Develop problem solving techniques and critical thinking skills in a business situation.
Demonstrate an understanding of internal structure and external relationship for companies doing business at an international level.
Demonstrate an understanding of the organisation and its management system.
Develop an ability to analyse information and to identify research question and to apply advanced research techniques and tools to create new literature which is justifiable and measureable.
Graduate Diploma in Business Administration learners need to complete all core units to a total of 120 credits to achieve the Graduate Diploma in Business Administration.
AssessmentModules are typically assessed by individual assessment.
Assessment involves investigative assignments to meet the assessment criteria detailed within each unit. Each unit contains 100% marks based on one assignment of 3000-3500 words.
Advance Diploma in Business Administration OR Any equivalent qualification.
The Graduate Diploma in Business Administration provides range of knowledge and skills relating to international business, entrepreneurship, management and leadership, finance, marketing, business law, sales force management and research methods for managers. Graduate can utilise those skills to find a good and well paid job in all areas of management and administration.
Candidates that successfully complete the Graduate Diploma in Business Administration will progress into University Certificate stage in Master Degree. Learners can also apply to the EBMA Postgraduate Diploma in Business Administration where they can progress onto the MBA/MA/MSC degree.


Few vocalists have pushed the boundaries of their art like the Norwegian vocalist and sound artist Stine Janvin (ne Stine Janvin Motland). The Berlin-based musician started out in improvised music, but she's embraced more radical techniques over the last half-decade she's constructed a sonic world that she alone inhabits. While she possesses a deep vocabulary of extended techniques, she's consistently sought at recontextualizing what human voice is capable of. She made her stunning 2014 album In Labour (Pica Disk) with fellow Norwegian sound artist Lasse Marhaug, situating her voice in a wide variety of environments where ambient noise served as a crucial component.
She's been pretty quiet on the recorded front in the last five years, but last week she made a powerful return with Fake Synthetic Music (PAN), a mind-warping solo project that's left my head spinning. Using a variety of electronic manipulations she transforms simple utterances into a visceral experience, by turns maddening and harrowing. The recording is aural representation of a rigorous live performance practice she's developed that also deploys lights and spatial distribution. I'm dying to experience it live, but the recording itself is mindfuck that needs no other help to make a deep impression. In the press materials Janvin says, "...I wanted to explore how I could vocalize in a way that would combine architectural sound with dance floor sequences," she says. While PAN often releases music that inventively subverts club music, Fake Synthetic Music goes so much further from anything used for a dance floor I have trouble parsing the connections.
Her source material seems to consist of little more than high-pitched swoops, screams, gurgles, and sweet if ominous long tones that are intensely extended, chopped-up layered, and wildly transformed by computer manipulations. There's a kind of watery bubbling sound on "Lips" that doesn't sound remotely human--and probably isn't it--but most of the tracks on the new album contain a vocal core, and by the time the fourth piece, "Like Right Now," explodes from the speakers, Janvin makes use of little else, crafting granular sound bombs that often sound like a police siren gone berserk, as rising and falling pitches produce violent psychoacoustic effects that would drive conservative listeners insane. The tonal interference and acoustic beating is unhinged, with very few outside textures or elements to soften the blow--there are some squiggling, far away bass tones on unknown provenance on "Like Last Night." Her pitch control is impressively precise, but this recording is more concerned with what she can electronically with her voice. Below you can check out a piece called "Tripple A." Hold tight.


It finally warmed up in Chicago! We had a high of 64 degrees and it felt soooooo nice! I could tell everyone was in a good mood. No joke, Chicago is a completely different city when it is nice out. It was so nice out that I could not resist but bust out my striped dress from The Shopping Bag, and guess what… I was comfortable wearing it out! I decided to keep it casual and layer with a denim vest for a transitional look. I love this dress. It's classic, comfortable, and versatile. I can easily come up with several ways to style it. I can have a girls night out by pairing it with a strappy heels or mules or style it in the Fall with booties. The best part is that it is affordable and less than $50. Want to know something even better? You can get additional 25% off just by entering the code RDOBSESSIONS at checkout. It's not just the dress, you can get 25% off of anything in The Shopping Bag. Head here to check out all their goodies. Trust me, you won't be disappointed!
Thanks Sara! It's one of my faves too!
LOVE ! Simple yet chic! Can't wait for warm weather to finally arrive here as well!
Love this casual look, girl! Yay for warmer weather – finally!
Love this casual dress!! You look gorgeous!
I love the chic striped dress – it fits you perfectly!
Super cute look! I love this dress with the denim vest you look great!
Love this stripe dress with the denim vest! Such a great casual look!
You look AMAZING!! Swooning over your your adorable dress! Sending you much love!
That's such a cute dress and the fit is impeccable! Love it on you, Rach!
Such a great Outfit. happy easter!
love the entire look 🙂 perfect for a casual weekend!
Love the striped dress with the Converse shoes!! Cute and casual!
So glad to hear it warmed up a bit for you! Where I live and Chicago seem to have very similar forecasts. Hopefully this sticks around and we really have seen the last of that dreaded snow! Have an excellent weekend Rach!
Yes, I'm so excited! Now just crossing fingers for the both of us that the weather stays this way!
I love this look! That striped dress is perfection, and I love how your paired it with the denim vest!
Thanks Katy! Thanks for stopping by!
Yay for spring! I love this look. The sneakers are so fun with your dress.
Such a perfect combo! Love the vest!
Such a beautiful, easy to put together casual weekender look!
Thanks Chelsea 🙂 I love walking around and buying flowers!
We love a dress that can take on the personality of it's accessories. Love that you can so easily dress it up for down, and to boot, it's way too cute on you. Loving those flowers!!
Oh my gosh, this outfit is so cute! Love the stripes paired with the denim vest…such a perfect combination!
Great combo! Love the stripes with the denim!
Cute outfit! Love the black and white striped dress!
Love this look! It's so effortless, simple but so chic! You look stunning!
Lovely dress. Thanks for sharing.
i'm loving this whole look , perfect for spring , i love the denim vest. Happy Easter to you!
Thanks Uzo! 🙂 Thanks for stopping by and hope you had a wonderful Easter!
stripes and denim += the best combo ever !


Bouqs. They're driving me crazy.
Does anyone update this blog anymore? Geesh.
Well, this news this morning just about broke my heart in two. Let's just give everything away, shall we?
So, the last couple of weeks? Oy vey, you know what I'm saying? You probably do – because I haven't really been able to shut up about it – but let me elaborate in writing. Thanks in advance.
On Sunday, April 26, my mom and Mollybear & Phoebe and I were heading out of Shawano (after attending my godson's spectacular first communion party) when I slumped over in the driver's seat (because I was driving) and became unconscious. I can't imagine what this must have been like for my mom. I know that she, and the rest of my family, handled it beautifully, though, because when Molly talks about it she laughs and says that I got sick and that she and Steve then went to a party and ate hot dogs. I remember nothing of the event itself and even the moments after are very foggy. For example, I distinctly remember throwing up in the ambulance, but I remember neither walking to the ambulance, which I'm told I did, nor getting from the ambulance to the hospital bed. While at the hospital (or medical center, as I guess it's more accurately called), I had a bunch of heart, brain and blood tests. Nothing looked too out of the ordinary and, after a decent amount of time with Ibuprofen and fluids inside of me, I was sent on my way with a diagnosis of having suffered a grand mal seizure and two directions: (1) no driving for three months and (2) call my primary doctor the next day to get a referral to neurology.
On Monday, April 27, I called my primary physician. I told the nurse that I was directed to ask for a referral to neurology. Instead, I was told that I would first need to be seen by an internist and the next available appointment for that wasn't until Friday. Uh, ok. I took Monday, Tuesday and part of Wednesday off of work because I couldn't move without significant muscular pain (for example, my jaw hurt like the dickens and moving from one position to another would have been comical if it weren't so painful) and I was uncommonly sleepy. When Friday came, I went through the hoops of the appointment. I relayed everything that I remembered and I gave a written report of what my mom had observed. I brought all of the paperwork from Shawano, including a DVD of the CT scan of my brain. I just kept thinking, "Answer the questions and we'll move this along." I did all of the muscle tests that were asked of me (push here, resist here, etc). The appointment must have lasted an hour. At the end of it? I was referred to a neurologist. First, though, she asked that I do more blood tests and another EKG. I complied and the tests were all returned with mostly normal results ("Good news!" read the note to me). I was told that Neurology (I'm going to capitalize it from now on, just because) would call me, but that if I didn't hear from them by Tuesday, I should call the office.
On Monday, May 4, I woke up with a horrible sore throat. I mean, ouch. But, I also had a bit of a cold so I thought that maybe it was related. We took Mollybear in for a dental appointment (during which she sat on my lap and cried, "I want my mommy!" – always confusing for everyone), then to school and then we went to work. My throat pain wasn't abating and I realized I'd had chills throughout the night. Hmm. I called the doctor and made an appointment, worrying that it might be strep. I had my performance review at work at 10 and asked Aaron to take me home around maybe 11. I just wasn't feeling right. I slept for a bit and Aaron picked me up at 2:30 to take me to my appointment. I went in, described my symptoms and was told, unequivocally, that I did not have strep throat. No swab was taken, no test performed. Although the resident said some of my lymph nodes were a little swollen, he was certain it was not strep, but was instead viral. He told me to come back if it got worse. I went home and felt kinda embarrassed. When I woke up on Tuesday, I felt no change in my condition, but I certainly felt like something was wrong. Even if this was *just* viral, it wasn't feeling very good. I needed to stay home. As the day went on, things got worse. The pain in my throat extended up to my ear. It no longer hurt only when I swallowed, but all the time. I measured a temperature of 100.6. This just couldn't be right. But I'd felt dismissed the day before, so I doubted myself and continued to hope that the pain would subside soon.
On Tuesday afternoon, I called my primary doctor's office to relay that I had not yet heard from Neurology. The response? Here's their number. Uh, ok. So, I called Neurology and explained the situation. The nice woman on the other end of the phone said, "Well, we've actually asked your doctor to request a couple of tests be performed before we see you and she has not yet ordered those tests. Let me transfer you back to their office, but I'll explain to them first what we need." So, I get transferred back and the guy to whom I'm transferred said to me – earnestly – "Ok, great, I'll get the ball rolling on this!" Uh, ok. It's been nine days now since I had the seizure.
On Wednesday, May 6, I woke up and felt terrible. Every time I swallowed, my body made a large jerking motion to try to offset the pain. I couldn't talk without pain. I couldn't breathe without pain. Whatever this was, I needed help. Ibuprofen hadn't alleviated any discomfort since Monday evening. Enough is enough. I just couldn't take it anymore. We dropped Molly off at school (well, AO did; I was far too reluctant to go near all of those kids) and he took me to Urgent Care. I walked in and asked to be seen. The woman at registration was so kind. The nurse who led me back to the exam room was mostly nice, but when I requested that we skip the scale – honestly, since turning 39 I feel more confident in asking to skip the scale at most appointments, but why on earth would anyone need to be weighed to determine if they have strep? Plus, I'd had it! I didn't want to take any more time to do any of this nonsense! – she said, "Ok, I can put down that you refused." Uh, ok, put that down. You do that. The nurse took my blood pressure and pulse and temperature (100 even) and became more sympathetic as her tasks wore on. She took a swab of my throat and left. The NP then came in and I almost started to cry immediately. She was so kind and caring and she listened so well. She looked at my throat and told me that no matter what the test results were, she was getting me medicine because things looked terrible. In about three minutes' time, the test results came back. Positive. I had strep. I actually started to cry. I felt so validated. She sent me on my way with a prescription for penicillin, three Ibuprofen and a bottle of apple juice. Praise modern medicine and health care providers who listen.
I went home. She said that I needed to stay home for 24 hours. While I didn't feel immediately better physically, I felt entirely different mentally. I felt listened to. I felt respected. I felt, weirdly maybe, vindicated.
This morning, Thursday, May 7, I realized that I had missed a phone call from my doctor's office that came in yesterday after 4 p.m. The voice mail just said to return the call from someone I'll call Jennifer. Around 8:15 a.m., on the way to take Molly to school, I returned the call. I was told that Jennifer was busy, but she would call me back. Around 11:20, Jennifer called back to tell me that Neurology had requested an EKG and an EEG. She said that I could come in anytime for an EKG, but that I'd have to wait for a call from a specialized scheduler for the EEG test. Ok, I thought, kinda puzzled. I hung up the phone, relayed the info to Aaron via text, and quickly checked MyChart. I thought, "Didn't I have an EKG on Friday? Isn't that what that was? And didn't I have one in Shawano? Why would I now need a third one? And why would Neuro want yet another one?" I quickly called my doctor's office back and – against all odds! – was actually able to speak to Jennifer during this same phone call! I said, "I think I had an EKG on Friday. I think Dr. X ordered it." Jennifer gave me a weird answer to something that I hadn't said, but eventually confirmed, yes, indeed, I had had an EKG on Friday and, oh wait, that's not what Neuro had asked for at all. Turns out, Neuro had asked for an EEG and an MRI of my head, something my doctor had not previously ordered. Oops! Ok, they will get on that now (four days after Neuro had requested it) and I will, once again, wait for a specialty scheduler to call me.


text:
Improving classification of low-resource COVID-19 literature by using Named Entity Recognition
Oscar Lithgow-Serrano, Joseph Cornelius, Vani Kanjirangat, Carlos-Francisco Méndez-Cruz, Fabio Rinaldi
Lithgow-Serrano, Cornelius, Kanjirangat, Méndez-Cruz, and Rinaldi: Improving classification of low-resource COVID-19 literature by using Named Entity Recognition
Oscar Lithgow-Serrano 1* , Joseph Cornelius 1 , Vani Kanjirangat 1 , Carlos-Francisco Méndez-Cruz 2 , Fabio Rinaldi 1
1Dalle Molle Institute for Artificial Intelligence Research, IDSIA USI-SUPSI, Polo universitario Lugano-Campus Est, Via la Santa 1, CH-6962 Lugano, Switzerland
2Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Avenida Universidad s/n Col. Chamilpa, 62210 Cuernavaca, Mor., Mexico
*Corresponding author: E-mail: oscarwilliam.lithgow@idsia.ch
Received March 17, 2021 Revised August 6, 2021 Accepted August 12, 2021
Automatic document classification for highly interrelated classes is a demanding task that becomes more challenging when there is little labeled data for training. Such is the case of the coronavirus disease 2019 (COVID-19) clinical repository—a repository of classified and translated academic articles related to COVID-19 and relevant to the clinical practice—where a 3-way classification scheme is being applied to COVID-19 literature. During the 7th Biomedical Linked Annotation Hackathon (BLAH7) hackathon, we performed experiments to explore the use of named-entity-recognition (NER) to improve the classification. We processed the literature with OntoGene's Biomedical Entity Recogniser (OGER) and used the resulting identified Named Entities (NE) and their links to major biological databases as extra input features for the classifier. We compared the results with a baseline model without the OGER extracted features. In these proof-of-concept experiments, we observed a clear gain on COVID-19 literature classification. In particular, NE's origin was useful to classify document types and NE's type for clinical specialties. Due to the limitations of the small dataset, we can only conclude that our results suggests that NER would benefit this classification task. In order to accurately estimate this benefit, further experiments with a larger dataset would be needed.
Keywords: classification, COVID-19, Named Entity Recognition, NLP
The current pandemic took the world by surprise in all aspects, among which is the efficient broadcasting of relevant findings to reach interested researchers, clinicians and other stakeholders. The medical literature relevant to coronavirus disease 2019 (COVID-19) is growing exponentially and, doctors, clinicians, and health workers in general need tools for monitoring and prioritizing the literature to make the most of their time by allowing them to quickly identify the most relevant information.
We have witnessed an enormous effort and solidarity that experts around the world have put in contributing and sharing a broad scope of experiences and findings. In this paper we consider in particular the case of an interinstitutional COVID-19 cooperation group (https://covid19.ccg.unam.mx/) which has been working to provide tools and resources for COVID-19 literature exploration.
The main contribution of the group is a clinical repository consisting of continuously updated academic literature related to COVID-19 (https://covid19.ccg.unam.mx/repoinfo.html). Considering the PRECEPT [1] scheme, their clinical experience and, other common classifications, the group has adopted a 3-way classification strategy to organize the repository to make it easier for potential users to find relevant literature. Despite a big effort to read and manually classify these documents, the pace of production of this literature hamper the utility of this work. In response the group has been working on automatic document classification machine learning models (https://covid19.ccg.unam.mx/machinelearning.html), however the number of classes, the interconnected nature of the clinical fields and the very little labeled examples imposes considerable challenges [2,3].
On the other hand, another important contribution has been the inclusion of a specialized COVID-19 named-entity annotation service, OntoGene's Biomedical Entity Recogniser (OGER) [4]. OGER is an annotation tool that performs Named Entity Recognition and Disambiguation (NERD) using shallow and deep dependency parsing combined with state-of-the-art machine learning techniques. It interacts with The Bio Term Hub (https://covid19.nlp.idsia.ch/bth.html) which enables OGER to process and link named entities from major life science databases: cellosaurus, cell ontology, ChEBI, CTD, EntrezGene, Gene Ontology, MeSH, Molecular Process Ontology, NCBI Taxonomy, Protein Ontology, RxNorm, Sequence Ontology, Swiss-Prot, Uberon.
Aiming to leverage the convergence of both contributions we hypothesized that the named entities recognized by OGER could be used as a free-lunch feature augmentation strategy to boost the classification performance [5,6].
During the Biomedical Linked Annotation Hackathon 7 (https://blah7.linkedannotation.org/) within the task "Analyzing COVID-19 literature with OGER" we proposed a subtask oriented to investigate this hypothesis (https://coree.github.io/blah7/task3.html).
The task's aim was to classify COVID-19 literature according to three independent dimensions: clinical specialties, types, topics-and-subtopics, with special emphasis in exploring the use of Named Entities to better leverage the title, abstract and text during classification.
Here, we present a proof-of-concept experiment performed during the hackathon. We processed the literature with OGER and used the resulting identified named-entity-recognition (NER) and their links to major biological databases (NED) as extra input features for a basic classifier model. We then compared the results with the same classification model but without the OGER extracted features. Although very preliminary, the results are promising and show a clear gain on COVID-19 literature classification by using named-entity-recognition as an auxiliary feature augmentation step, suggesting the benefit of NER for this task.
In the preprocessing phase the original PDF documents were converted to text using the Linux utility pdftotext and no other cleaning or normalization steps were performed.
Next, the documents' title and full text were converted to features applying Term Frequency-Inverse Document Frequency (tf-idf), Latent Semantic Analisis (LSA), and using the CLS embedding (first embedding) of the pretrained BERT-base as a sentence-embedding [7].
Besides, the full-text was processed with the OGER's API specialized for COVID-19 applications (https://pub.cl.uzh.ch/projects/ontogene/oger/upload/txt/tsv?dict=509f822aaf527390). This process resulted in an average of 1,622 annotations per article (The same token can be annotated as multiple entities because OGER uses multiple sources) including, among others, the entity type (e.g., organism, disease) (The full list of entity types annotated by OGER in this dataset were: organism, sequence, cellular_component, clinical_drug, cell_line, organ/tissue, gene/protein, chemical, cell, disease, molecular_process, biological_process, molecular_function), the matched term (e.g., coronavirus), the preferred-form (e.g., coronavirus), the entity ID and, the origin database (e.g., MeSH diseases, CTD MeSH). OGER has the capacity to return results in different formats, for our purpose TSV was the most convenient (Table 1 for an output example).
The classification task was approached as a multi-class problem for each of the three classification axis; this is, each document can be labeled with at most one topic, one type, and one specialty.
The general approach to use the NERD results consisted in treating each field of OGER output as an alternative representations of the documents and, then, apply different feature extraction over these representations (Fig. 1). To create each representation, all the values of one field of the OGER results were joined as words, with a space as separator. For example, to obtain the preferred-form representation of a document, all the value of the preferred-form field of all the identified entities in the document were concatenated. The resulting string is then treated as if it were an additional sentence in the input text and thus, converted using two basic feature extraction strategies: tf-idf and LSA.
The result was 11 features: six corresponding to the tf-idf, LSA and bert-embedding (Due to the BERT model limitation, we use only the first 512 tokens of the article body to build the text embedding) for the document's title and the text representations, and 5 from the NERD extraction: tf-idf of the type, tf-idf and LSA [8,9] of the preferred-form, tf-idf of the entity-id and, tf-idf of the origin. These features were later reduced (independently for each classification axis) through a supervised exhaustive feature selection with a Support Vector Machine (SVM) [10] on a 3-fold cross validation, i.e., through a greedy search evaluating with the SVM classification model all possible combinations of features.
The final validation consisted in training the selected model (the SVM with the reduced features) on a stratified split corresponding to the 80% of the labeled dataset and, test it in the remaining 20%. This was repeated in 30 runs with random train-test split.
One possible limitation of this study is that we performed the search for the best features combination by 3-fold cross-validation in the full dataset. This was done because the dataset was very small, highly unbalanced and some classes had only three examples. Although in the final validation phase training and testing were done in clearly separated subsets of the original data, further experiments with more data are needed to validate the observed benefits.
The set of manually labeled documents from the clinical repository was used for these experiments.
It is worth noticing that the labeled dataset consists of 646 articles with a rounded average of 12 words for the title and 3,540 for the body. However not all documents are classified in each of the 3-classification axis: the Document type classification (e.g., observational studies, systematic reviews) has 269 examples for the 6 classes; the Clinical specialties classification (e.g., immunology, Cardiology) has also 269 examples but for 36 classes; and the Topic & Subtopic classification (e.g., epidemiology, diagnosis) counts 383 examples for the 16 topics and 161 examples for the 27 subtopics. Moreover within each classification axis the examples are not uniformly distributed through the classes.
The baseline was selected as the model with the best combination of features extracted from the document title and text, i.e., without the NERD results. In this case, the best baseline model was obtained by using the tf-idf of the title and LSA of the text.
For the Document type classification, the selected features were: tf-idf of the title, LSA of the text and tf-idf of the NE origin. The F1-weighted mean of the 30 validation runs was 0.739 (s = 0.041 [sample standard deviation]) and, by including the NE origin as feature the classifier had a significant 10% gain (t-test with p < 0.05) compared to the 0.669 (s = 0.044) F1-weighted score of the baseline (Table 2).
In the specialty classification the best model consisted of the features tf-idf of the title, LSA of the text and tf-idf of the NE type. This combination resulted in a statistically significant 8% gain in the F1-weighted mean compared to the baseline, 0.646 (s = 0.044) versus 0.597 (s = 0.048).
Finally, for the topic classification the best features were tf-idf of the title, LSA of the text and tf-idf of the NER origin. The F1-weighted mean of the 30 runs for this model was 0.599 (s = 0.051) whereas the baseline scored 0.595 (s = 0.049). Although this represented an improvement of 0.8%, it was not statistically significant. Fig. 2 shows the comparison of the results mentioned above.
It is worth noticing that the pdf to text conversion was done using a basic approach which produces quite noisy results, i.e., the extracted text includes lines that are not complete sentences due to how they are displayed in the PDF; it also includes statements interrupted by spurious chunks of text like footnotes, page numbers, etc. and other kinds of not cleanly extracted text. This might explain why BERT features played no role, and was detrimental to the OGER processing and the quality of its results.
Interestingly, we found that the named entities' type and origin, i.e., more general features, were more informative for the classification than the more specific ones, like the matched term, the preferred-form, and the entity ID. One possible explanation is that due to the granularity of the general features, there are more examples in the training data and, thus, the estimator can better learn the relation between those features and the target classes. The fact that NE's type (e.g., organism, disease) helped classify specialty may unveil an interesting pattern where some biomedical entities are more prevalent in some specialties. On the other hand, the fact that using the NE origin (MeSH diseases, CTD MeSH) improved document type classification is an interesting finding that should be further investigated. These experiments also opened the question of whether using BioBert Embeddings, trained for Biomedical Domain, instead of general Bert Embeddings may help classification.
It is important to stress that these were proof-of-concept experiments, and bearing in mind the methodological limitations due to the small dataset the conclusions here presented are only suggestive, and further experiments with more data are needed to accurately estimate the observed benefits of NER in the classification task.
Finally, it is important to highlight that due to the limited time in the hackathon, the experiments presented here were applied and compared to a baseline and not to the classification strategy that the COVID-19 cooperation group is developing. The next step would be to investigate if similar gains could be obtained when integrating NERD features in that strategy and applied to a larger dataset.
Conceptualization: OLS. Data curation: JC, VK. Formal analysis: OLS. Funding acquisition: FR. Methodology: OLS, FR, CFMC. Writing - original draft: OLS. Writing - review & editing: FR, CFMC, VK, JC.
The code and data are available at https://github.com/IDSIA-NLP/blah7/tree/task3/task3
We are grateful to the organizer of the Biomedical Linked Annotation Hackathon 2021 for the opportunity to work collaboratively on this project and share it with the other participants.
Schematic representation of the experiment pipeline. At the top half, feature extraction of documents, titles, and full-text was done with tf-idf and LSA techniques, respectively. At the bottom half, documents were first processed with OGER, and then different feature extraction strategies were applied over the extracted NERD fields. Tf-idf was applied to the origin and entity-ID values and LSA to preferred-form. Finally, an exhaustive search of feature combinations with an SVM classifier was performed. tf-idf, Term Frequency-Inverse Document Frequency; LSA, Latent Semantic Analisis; OGER, OntoGene's Biomedical Entity Recogniser; NERD, Named Entity Recognition and Disambiguation; SVM, Support Vector Machine.
Comparison of results distributions between baseline and the best model using Named Entity Recognition and Disambiguation (NERD) features for each classification axis.
Fragment exemplifying an OGER output in TSV format
Matched term
Preferred form
Disease 42 50 COVID-19 COVID-19 C000657245 MeSH supp (Diseases)
Organism 126 137 Coronavirus Coronavirus D017934 MeSH desc (Organisms)
Disease 138 145 COVID19 COVID-19 C000657245 MeSH supp (Diseases)
Disease 151 159 COVID-19 COVID-19 C000657245 MeSH supp (Diseases)
Chemical 776 785 Antiviral Antiviral agent CHEBI:22587 ChEBI
Chemical 907 910 com Coenzyme M CHEBI:17905 ChEBI
Clinical_drug 944 955 Chloroquine Chloroquine 2393 RxNorm
Chemical 944 955 Chloroquine Chloroquine D002738 CTD (MESH)
OGER, OntoGene's Biomedical Entity Recogniser; COVID-19, coronavirus disease 2019.
Best model results per classification axis
Classification axis
Baseline model
Model with NERD features
Document type 0.669 (s = 0.044) 0.739a (s = 0.041)
Specialty 0.597 (s = 0.048) 0.646a (s = 0.044)
Topic 0.595 (s = 0.049) 0.599 (s = 0.051)
Values are the average of the F1-weighted mean of 30 runs; s, sample standard deviation.
NERD, Named Entity Recognition and Disambiguation.
a The difference is statistically significant.
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text:
\section{Introduction}
\label{sec:intro}

As is well-known, Casimir and Polder~\cite{CP48} calculated the interaction
energy between an atom in its ground state and a perfectly reflecting plate
and obtained the result
\begin{equation}
V = - \frac{1}{4 \pi z^3}\, \int_0^\infty d\xi \, \alpha(i \xi) \,
 (2  z^2 \xi^2 + 2 z \xi +1)\, {\rm e}^{-2 z \xi} \, , \label{eq:CP}
\end{equation}
where $z$ is the distance between the atom and the plate and $\alpha(i \xi)$
is the atomic polarizability evaluated at imaginary frequency. In the limit
of large $z$, this potential takes the simple form
\begin{equation}
V \sim V_a = - \frac{3\, \alpha(0)}{8 \pi\, z^4}\,,   \label{eq:CPA}
\end{equation}
which can be interpreted as due to the interaction of the atom with
the quantized electromagnetic field. In particular, the asymptotic
Casimir-Polder potential can be expressed as
\begin{equation}
 V_a = - \frac{1}{2} \alpha(0) \, \langle {\mathbf E}^2 \rangle =
\frac{\alpha(0)}{4 \pi \, z^3}\, \int_0^\infty d \omega\,
 \Bigl[(2\,\omega^2\,z^2 -1) \sin 2\omega z
+ 2\,\omega\,z \cos 2\omega z \Bigr] \,.  \label{eq:Va}
\end{equation}
Here $\langle {\mathbf E}^2 \rangle$ is the shift in the mean square
of the quantized electric field due to the plate, and the integral on
$\omega$ is understood to be evaluated by use of a convergence factor.
For example, insert a factor of ${\rm e}^{- \beta \omega}$ in the integrand,
and then take the limit $\beta \rightarrow 0$ after evaluation of the integral.
The integrand is a function which is highly oscillatory, and the area under
each oscillation is much larger than the final result for the integral.
Thus, if one could slightly modify the frequency spectrum, which is the
integrand in Eq.~(\ref{eq:Va}), both the magnitude and sign of the result
could be dramatically altered. The Casimir effect between parallel plates
also exhibits a quasi-oscillatory spectrum~\cite{Ford88,Hacyan}, and
the possible effects of its modification were discussed in
Ref.~\cite{Ford93}.

In a previous paper, Ref.~\cite{F98}, the force on a small dielectric
sphere in the presence of a perfectly reflecting plate was discussed.
It was shown that the interaction of the sphere with the quantized
electromagnetic field produces a quasi-oscillatory force whose magnitude
can be much larger than the force associated with the asymptotic
Casimir-Polder potential, Eq.~(\ref{eq:CPA}). This result suggests
a modification of the frequency spectrum of vacuum fluctuations.
More recently, the model in Ref.~\cite{F98} was extended to include
finite reflectivity of the wall and finite temperature effects~\cite{SF04}.
However, Barton~\cite{Barton04} has suggested that the results in
Refs.~\cite{F98} and \cite{SF04} are incomplete in that they do not
include a contribution from the quantum charge fluctuations
in the sphere, and that this effect will cancel the quasi-oscillatory terms
when the sphere is in its ground state.
 This contribution, also known as radiation reaction
or the effect of plasmonic modes, arises from the retarded self-interaction
of  quantum charge fluctuations in the presence of the mirror.

As will be discussed below, Barton's suggestion is correct; the
quasi-oscillatory terms cancel for the ground state, but not for other
quantum states of the plasma in the sphere, which is essentially a three
dimensional quantum harmonic oscillator. In this way, the sphere behaves
just as does an atom. An atom in its ground state has the attractive
interaction found by Casimir and Polder, Eq.~(\ref{eq:CP}), but an atom
in an excited state has a quasi-oscillatory interaction potential with the
plate~\cite{Barton74}.

In Sect.~\ref{sec:vacuum}, the vacuum mode contribution found in
Ref.~\cite{F98} will be reviewed. The contribution of the charge fluctuations
will be computed in Sect.~\ref{sec:plasmon}, and the results will be
discussed in Sect.~\ref{sec:final}.

\section{Contribution of the Quantized Electromagnetic Field}
\label{sec:vacuum}

In this section, we will summarize the results of Ref.~\cite{F98}
concerning the
force due to the vacuum modes, or the quantized electromagnetic field.
If one has a polarizable particle with dynamic polarizability
$\alpha(\omega)$
located a distance $z$ from a perfectly reflecting plane, the force on the
particle may be computed from the Maxwell stress tensor. The vacuum modes
in the presence of the plate consist of a linear combination of an incident and
a reflected wave. Each of these interacts with the particle and creates a
radiated dipole field. The force on the particle arises from cross terms
between (1) the  reflected wave and the dipole field induced by the incident
wave, and (2) the incident wave and the dipole field induced by the reflected
wave. After integrating over all modes, one finds the net force to be
\begin{eqnarray}
F_V &=&   - \frac{1}{4\pi z^4} \int_0^\infty d \omega \, \alpha_1(\omega)\,
   \nonumber \\
 &\times&    \Bigl[ 3\sin 2\omega z -6 z\,\omega\, \cos 2\omega z
 -6 z^2\,\omega^2\,\sin 2\omega z
  + 4z^3\,\omega^3\,\cos 2\omega z \Bigr] \,.  \label{eq:force4}
\end{eqnarray}
Here $\alpha_1(\omega)$ is the real part of $\alpha(\omega)$.
The appearance of the real part of the dynamic polarizability is a crucial
feature of this result for $F_V$. Equation~(\ref{eq:force4}) is derived
using a dipole approximation which requires the sphere to be small compared
to both the distance to the plane, $z$, and to the characteristic wavelengths
associated with $\alpha_1(\omega)$.

Now consider a sphere of radius $a$ composed of a uniform material with
dielectric function $\varepsilon(\omega)$. The complex polarizability is given
by
\begin{equation}
\alpha(\omega) = a^3\, \frac{\varepsilon(\omega) - 1}{\varepsilon(\omega) +2}
                              \,.  \label{eq:alpha}
\end{equation}
We will take the dielectric function to be that of the Drude model,
\begin{equation}
\varepsilon(\omega) = 1 - \frac{\omega_p^2}{\omega(\omega + i\gamma)} \,,
                                                \label{eq:epsilon}
\end{equation}
where $\omega_p$ is the plasma frequency and $\gamma$ is the damping parameter.
From Eqs.~(\ref{eq:alpha}) and (\ref{eq:epsilon}), we find that the real part
of the polarizability is given by
\begin{equation}
\alpha_1 =  a^3\, \omega_p^2\,
\frac{\omega_p^2 -3 \omega^2}{(3 \omega^2 -\omega_p^2)^2 + 9 \omega^2 \gamma^2}
                               \,.  \label{eq:alpha_1}
\end{equation}
Note that although $\alpha(\omega)$ has poles only in the lower half-$\omega$
plane, its real part $\alpha_1(\omega)$ has poles in both the upper and lower
half planes. In the context of this model, the sphere is required to be small
in the sense that $a \ll z$ and
\begin{equation}
a\, \omega_p \ll 1 \,.
\end{equation}

We can evaluate the integral in Eq.~(\ref{eq:force4})
by rotating the contour of integration
to the imaginary $\omega$-axis.
However, in this process we will also acquire
a contribution from the residue of the pole of $\alpha_1(\omega)$ at
$\omega = \Omega + \frac{1}{2}\, i\, \gamma$, where
 \begin{equation}
\Omega = \frac{1}{6} \sqrt{12 \omega_p^2 - 9 \gamma^2} \,.
\end{equation}
Here we are primarily interested in the limit of small damping, so we
will take the limit $\gamma \rightarrow 0$ after the integrals are evaluated.
In this limit,
 \begin{equation}
\Omega = \frac{\omega_p}{\sqrt{3}} \,. \label{eq:Omega}
\end{equation}

The force can be written as
\begin{equation}
F_V = J_V + P_V \,,
\end{equation}
where $J_V$ is the net contribution from integrals along the imaginary axis,
and $P_V$ is that from the pole.
The explicit forms of these two contributions for $\gamma = 0$ are
\begin{equation}
J_V = - \frac{a^3\, \omega_p^2}{4 \pi \, z^4}\, \int_0^\infty d \xi \,
\frac{(3 \xi^2 +\omega_p^2)(4 z^3 \xi^3 +6z^2 \xi^2 +6z\xi +3)}
     {(3 \xi^2 +\omega_p^2)^2 }\;  e^{-2 z \xi} \,,
                                                        \label{eq:J}
\end{equation}
and
\begin{equation}
P_V = - \frac{a^3\, \omega_p^2}{24 \,\Omega\, z^4}\,
\Bigl[ 2\Omega \,z\,(2\,\Omega^2\, z^2 -3) \sin (2\Omega z)
 + 3\,( 2\Omega^2\, z^2  -1) \cos (2\Omega z) \Bigr] \,.  \label{eq:P}
\end{equation}
Here  the positive direction is taken to be away from the plate, so
a positive value for the force indicates repulsion.

\section{Contribution of the Quantum Charge Fluctuations}
\label{sec:plasmon}

In this section, we will calculate the average force on the sphere
due to quantum fluctuations of the charge density in the sphere.
Here we consider only the case where $\gamma = 0$, so the plasma
oscillations are undamped, and have a resonate frequency at the pole of
$\epsilon(\omega)$, that is at $\omega = \Omega$ where $\Omega$ is given by
Eq.~(\ref{eq:Omega}).
Classically, the plasma forms a three-dimensional harmonic oscillator
with a frequency $\Omega$. When the electron gas is described quantum
mechanically, the plasma becomes a  three-dimensional quantum harmonic
oscillator.

First, let us consider  a classical oscillating dipole in the presence
of a perfectly reflecting plate located at $z = 0$. Let the instantaneous
dipole moment be given by
\begin{equation}
\mathbf{p}(t) = \mathbf{p_0}\, \cos \Omega t \,.
\end{equation}
The electromagnetic field radiated by this dipole is reflected by the plate
and returns to exert a reaction force on the dipole. Let $\mathbf{E}(t)$
and $\mathbf{B}(t)$ be the reflected electric and magnetic fields  at the
location of the dipole. The resulting force on the dipole is given by
\begin{equation}
\mathbf{F}_P = p^j\, \partial_j\, \mathbf{E} + \mathbf{\dot{p} \times B}\,.
\end{equation}
(This form can be derived directly from the Lorentz force law, and differs
slightly from the expression for the force used in Ref.~\cite{F98},
which was derived from the Maxwell stress tensor. However, one can show that
both expressions lead to the same time-averaged force.)

We are interested in the component of time-averaged force which is normal
to the plate. A lengthy but straightforward calculation leads to the
result
\begin{eqnarray}
F_P &=& \frac{p_{0x}^2 + p_{0y}^2}{32 \, z^4} \,
\Bigl[ (8 \Omega^2 z^2 - 3)\, \cos(2 \Omega z)
+ 2 \Omega z\,(4 \Omega^2 z^2 -3 ) \sin (2 \Omega z) \Bigr]   \nonumber \\
 &+& \frac{p_{0z}^2}{16 \, z^4} \Bigl[(4 \Omega^2 z^2 -3) \, \cos(2 \Omega z)
-6 \, \Omega z \, \sin (2 \Omega z) \Bigr] \,.
\end{eqnarray}

Now we need to briefly summarize the quantum mechanical description
of the plasma in the sphere. Suppose that there are $N$ free electrons
in the sphere, and that each electron is displaced by $\mathbf{u}$
from its equilibrium position during the plasma oscillations. The
Lagrangian for the plasma may be written as
\begin{equation}
{\cal L} = \frac{1}{2} N m (\mathbf{\dot{u}}^2 - \Omega^2 \mathbf{u}^2) \,,
\end{equation}
where $m$ is the electron mass. Thus the system is equivalent to a single
particle with mass $N m$ is a three-dimensional harmonic potential  with
resonant frequency $\omega$. The dipole moment of the system can be expressed
as
\begin{equation}
\mathbf{p} = N e \, \mathbf{u} \,,
\end{equation}
where $e$ is the electron charge.
When the system is  quantized,  the Cartesian components of  $\mathbf{u}$
can be expressed as
\begin{equation}
u_j = \frac{1}{\sqrt{2 N m \Omega}} \, (a_j + a^\dagger_j) \, ,
\end{equation}
where $a_j$ and $a^\dagger_j$ are the annihilation and creation operators,
respectively, for quanta in mode $j$.

We can make the link between the previous description of a classical
oscillating dipole and a dipole undergoing quantum fluctuations by
identifying  $\langle p_j^2 \rangle$,
the quantum expectation value of $p_j^2$, with the time-average
of the corresponding squared classical field. Thus, we can set
\begin{equation}
p_{0j}^2 = 2 \langle p_j^2 \rangle \,.
\end{equation}

If the oscillator is in its ground state, we have
\begin{equation}
\langle p_x^2 \rangle_0 = \langle p_y^2 \rangle_0 = \langle p_z^2 \rangle_0
= \frac{1}{2 N M \Omega} = \frac{a^3 \, \omega_p^2}{6 \Omega} \,,
\end{equation}
where we used the fact that
\begin{equation}
\omega_p^2 = \frac{4 \pi N e^2}{V m} = \frac{3 N e^2}{ a^3 m} \, ,
\end{equation}
where $V$ is the volume of the sphere.
Thus in the ground state, we find that $F_P = -P_V$. The force due to
the averaged charge fluctuations exactly cancels the quasi-oscillatory
term coming from the vacuum modes. The net force is then
\begin{equation}
F = J_V +P_V  + F_P = J_V \,,
\end{equation}
which is always attractive.

The situation is quite different of the quantum oscillator is not in its
ground state. In this case, we can write the net force as
\begin{eqnarray}
F &=& J_V + \frac{1}{16 \, z^4} \,
\Bigl(\langle p_x^2 \rangle - \langle p_x^2 \rangle_0 +
\langle p_y^2 \rangle - \langle p_y^2 \rangle_0 \Bigr)
\Bigl[ (8 \Omega^2 z^2 - 3)\, \cos(2 \Omega z)  \nonumber \\
&+& 2 \Omega z\,(4 \Omega^2 z^2 -3 ) \sin (2 \Omega z) \Bigr]   \nonumber \\
 &+& \frac{1}{8\, z^4} \,
\Bigl(\langle p_z^2 \rangle-\langle p_z^2 \rangle_0\Bigr)
\Bigl[(4 \Omega^2 z^2 -3) \, \cos(2 \Omega z)
-6 \, \Omega z \, \sin (2 \Omega z) \Bigr] \,. \label{eq:genstate}
\end{eqnarray}
Consider, for example, the case where the state of the oscillator contains
one quantum in a particular mode. For that mode, we will have
$\langle p_j^2 \rangle = 2 \langle p_j^2 \rangle_0$, and $F$ will have a
quasi-oscillatory part which is just minus the vacuum contribution.
Note that Eq.~(\ref{eq:genstate}) is equivalent to
Barton's~\cite{Barton74} Eq.~(4.1).

A case of special interest is when the oscillator is in a coherent state
of each mode. In this case,
we have
\begin{equation}
a_j |\psi \rangle = \beta_j |\psi \rangle \,,
\end{equation}
 where $|\psi \rangle$ is the quantum state of the oscillator, and the
$\beta_j$ are three complex numbers. In this case, the net force becomes
\begin{eqnarray}
F &=& J_V + \frac{2 \sqrt{3} a^3 \omega_p}{48 \, z^4} \,
\biggl\{\Bigl[ ({\rm Re} \beta_x)^2 +  ({\rm Re} \beta_y)^2
\Bigl[ (8 \Omega^2 z^2 - 3)\, \cos(2 \Omega z)  \nonumber \\
&+& 2 \Omega z\,(4 \Omega^2 z^2 -3 ) \sin (2 \Omega z) \Bigr]   \nonumber \\
 &+&  2\, ({\rm Re} \beta_z )^2
\Bigl[(4 \Omega^2 z^2 -3) \, \cos(2 \Omega z)
-6 \, \Omega z \, \sin (2 \Omega z) \Bigr] \biggr\}\,.
\end{eqnarray}
Thus if the quantum state of the plasma is a coherent state with $|\beta_j|$
of order one, then there is a quasi-oscillatory force on the sphere which
is of the same order of magnitude as the vacuum contribution, $F_V$.

\section{Discussion and Conclusions}
\label{sec:final}

We have seen that plasmonic contributions, due to quantum charge fluctuations,
give a significant  contribution to the force on the sphere. When these modes
are in their ground state, they exactly cancel the quasi-oscillatory terms
$P_V$ arising from the vacuum modes. In this case, only the vacuum mode
term $J_V$ which can be written as an integral over imaginary frequency
remains. Thus if one had ignored both the plasmon mode contribution and
the residues of the poles of $\alpha_1(\omega)$, one would have inadvertently
obtained the correct answer. When the plasmon modes are not in the ground
state, the net force is quasi-oscillatory.

In the context of atomic systems, there is an extensive literature on
the relative effects of vacuum modes and quantum charge fluctuations,
often called radiation reaction or self-reaction. See, for example,
Ref.~\cite{Dalibard} and \cite{MJH90}. However, many of the treatments
for atomic systems do not make it clear whether the separation between vacuum
and self-reaction effects is gauge invariant. In the present model, it
is obvious that the two effects are separately gauge invariant, as all
of the calculations involve field strengths rather than potentials.
When calculations are performed by doing second order perturbation theory
on a Hamiltonian, as in Refs.~\cite{CP48} and \cite{Barton74}, there is
no need to consider the effects separately, and the cancellation is
automatic.

In the case of the Casimir effect between planar geometries, the role
of plasmonic contributions at short distances has long been
recognized~\cite{VanKampen,Barton79}.
More recently, Intravaia and  Lambrecht~\cite{IL05} have argued that they
are significant at all separations.

It seems to be desirable to understand better the physical reason for
the cancellation between vacuum and plasmonic effects.  It is clear that
one way to upset the cancellation is to excite the plasmon modes.
However, it is less clear if this is the only way in more general
geometries.

\ack
I would like to thank Gabriel Barton for valuable criticism and discussions.
This work was supported in part by the National Science Foundation under
Grant PHY-0244898.

\section*{References}

redpajama_set_name: RedPajamaArXiv


text:
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text:
Q: Singular varieties Let $y^2=x^3+ax+b$ and V be its affine variety. V is singular iff $y^2-x^3-ax-b$, 2y, and $3x^2+a$ have a common zero iff $x^3+ax+b$ and $3x^2+a$ have a common zero iff $x^3+ax+b$ has a multiple root.
Is it correct that the first iff occurs because elements of the variety are solutions to the polynomial equation, and 2y and $3x^2+a$ are the partial derivatives in terms of y and x respectively (which means the point is singular).
Also, could someone explain the next two 'iffs'

A: Let $f = y^2 - x^3 - ax - b$.
The first iff is the Jacobian test.  A point of $V = V(f)$ is singular if and only if the matrix of partial derivatives
$$\begin{bmatrix} \frac{\partial f}{\partial x} \\ \frac{\partial f}{\partial y}\end{bmatrix}$$
does not have rank $1$.  The only way this happens is if it's the zero matrix, so if $2y$ and $3x^2 + b$ are both zero.  The reason $f$ is also in this list is to ensure that you're talking about a point in $V$.
For the second iff note $2y = 0$ means $y = 0$ so we can plug this into the other polynomials and get $-(x^3 + ax + b)$ and $3x^2 + a$.
Finally observe that $3x^2 + a$ is the derivative of $x^3 + ax + b$.  It's well known that a polynomial has a solution in common with it's derivative if and only if that polynomial has a repeated root.  To prove this write $p(x) = (x - c)^n\cdot g(x)$ and assume $c$ is not a root of $g(x)$.  Now just take the derivative of $p(x)$ and check whether $a$ is also a root.  You'll find that it is when $n > 1$ but it is not when $n = 1$.

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