text:
Ibolja Cernak
Mercer University School of Medicine, United States
Tim Harrigan
Johns Hopkins University, United States
Ginu Unnikrishnan
BlueHalo, United States
King Yang
Wayne State University, United States
Front. Neurol., 09 June 2021
Sec. Neurotrauma
Volume 12 - 2021 | https://doi.org/10.3389/fneur.2021.658461
Reproducibility and Characterization of Head Kinematics During a Large Animal Acceleration Model of Traumatic Brain Injury
Andrew R. Mayer1,2,3,4*, Josef M. Ling1, Andrew B. Dodd1, Julie G. Rannou-Latella1, David D. Stephenson1, Rebecca J. Dodd1, Carissa J. Mehos5, Declan A. Patton6, D. Kacy Cullen7, Victoria E. Johnson7, Sharvani Pabbathi Reddy1, Cidney R. Robertson-Benta1, Andrew P. Gigliotti1, Timothy B. Meier8,9,10, Meghan S. Vermillion1, Douglas H. Smith7 and Rachel Kinsler11
1The Mind Research Network/Lovelace Biomedical Research Institute, Albuquerque, NM, United States
2Neurology Department, University of New Mexico School of Medicine, Albuquerque, NM, United States
3Psychiatry Department, University of New Mexico School of Medicine, Albuquerque, NM, United States
4Psychology Department, University of New Mexico School of Medicine, Albuquerque, NM, United States
5Neurosciences Department, University of New Mexico School of Medicine, Albuquerque, NM, United States
6Center for Injury Research and Prevention, Children's Hospital of Philadelphia, Philadelphia, PA, United States
7Department of Neurosurgery and Penn Center for Brain Injury and Repair, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
8Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, WI, United States
9Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI, United States
10Department of Biomedical Engineering, Medical College of Wisconsin, Milwaukee, WI, United States
11Enroute Care Group, U.S. Army Aeromedical Research Laboratory, Fort Rucker, AL, United States
Acceleration parameters have been utilized for the last six decades to investigate pathology in both human and animal models of traumatic brain injury (TBI), design safety equipment, and develop injury thresholds. Previous large animal models have quantified acceleration from impulsive loading forces (i.e., machine/object kinematics) rather than directly measuring head kinematics. No study has evaluated the reproducibility of head kinematics in large animal models. Nine (five males) sexually mature Yucatan swine were exposed to head rotation at a targeted peak angular velocity of 250 rad/s in the coronal plane. The results indicated that the measured peak angular velocity of the skull was 51% of the impulsive load, was experienced over 91% longer duration, and was multi- rather than uni-planar. These findings were replicated in a second experiment with a smaller cohort (N = 4). The reproducibility of skull kinematics data was mostly within acceptable ranges based on published industry standards, although the coefficients of variation (8.9% for peak angular velocity or 12.3% for duration) were higher than the impulsive loading parameters produced by the machine (1.1 vs. 2.5%, respectively). Immunohistochemical markers of diffuse axonal injury and blood–brain barrier breach were not associated with variation in either skull or machine kinematics, suggesting that the observed levels of variance in skull kinematics may not be biologically meaningful with the current sample sizes. The findings highlight the reproducibility of a large animal acceleration model of TBI and the importance of direct measurements of skull kinematics to determine the magnitude of angular velocity, refine injury criteria, and determine critical thresholds.
Although heterogeneous in nature, most human traumatic brain injuries (TBI) are caused by the transmission of energy from an external force to the head that subsequently results in rapid acceleration/deceleration of the brain with or without deformation of the skull (1). Head kinematics have therefore been used to predict TBI pathology in both human and animal models, design safety equipment, and assess the risk of brain injury (2–4). However, to our knowledge, there have only been a handful of large animal studies that have used sensors (5–9) and/or high-speed cameras [see Table 1; (8, 10, 11)] to directly measure the magnitude of head kinematics during acceleration models of injury. To date, no studies have evaluated the reproducibility of head kinematics, which, by definition (65, 66), requires the exact same initial injury conditions to be repeated across multiple animals (i.e., methods reproducibility) and/or in separate experiments (i.e., results reproducibility).
Table 1. In vivo models of non-invasive diffuse axonal injury.
Preclinical trauma models are generally categorized into contusional (e.g., weight drop, controlled cortical impact, and fluid percussion injury), blast, penetrating, and acceleration models (67–69). Acceleration models are conceptually similar to blast tertiary injury and are generally considered to be the best model for generating diffuse injury and mimicking human trauma (12, 69). Acceleration injuries have traditionally been classified (see Table 1 for a review) into impact (e.g., bolt guns, sled models with impact) vs. non-impact models (e.g., HYGE, sled models without impact) and can be performed with or without protective equipment (1, 67). Although rodent acceleration models have been proposed (70), examination of the effects of linear and rotational accelerative forces is more practical in gyrencephalic animal species with a larger brain mass (11, 71).
For example, it has been estimated that swine models require an approximately 8-fold increase in acceleration to mimic the forces typically experienced by humans (72). The additional advantages of acceleration models include minimal preparation time (15–20 min) due to lack of craniotomy (73). The primary critiques of acceleration models (1, 69) are related to the financial cost of both instrumentation (non-impact models only) and large animal species themselves, as well as the higher incidence of skull fracture (impact models).
Reproducibility is proposed to be a cornerstone of science (65). However, to our knowledge, there have been no large animal acceleration studies (see Table 1) establishing the reproducibility of head kinematics by either directly mounting a sensor to the animal's head or using high-speed video capture. The majority of previous studies have instead quantified kinematics from the machine used to produce the initial biomechanical forces and assumed a direct correspondence to subsequent head kinematics [e.g., (4)]. The five large animal studies to date that directly measured head kinematics with skull-mounted sensors varied the initial injury load conditions with no repeat tests (5–9). Although these seminal studies were critical for establishing injury criteria and relationships with pathology, they do not permit for the establishment of reproducibility. Head kinematics are routinely used to drive finite element models of head impacts in both animal and human trauma scenarios. Finite element analyses indicate that the magnitude of axonal strains correlates with the velocity and direction of head rotation, moment of inertia, age, and brain size during acceleration (2, 4). Therefore, having accurate measurements of the magnitude of head kinematics is a critical boundary condition for finite element analyses.
The current series of experiments therefore quantified the reproducibility of head kinematics in a swine acceleration model using the HYGE device and examined for potential differences between head and machine kinematics. The HYGE device represents one of the original (12, 13) and more widely used acceleration non-impact models (see the discussion and Table 1) and has more recently been adapted for neonatal, juvenile, and adult swine (32, 52, 59, 62). A single angular velocity level (250 rad/s) was targeted in the coronal plane to establish method reproducibility for head kinematics (65) as quantified by the coefficient of variation (COV) across animals. Specifically, the COV is a widely utilized statistical construct to quantify dispersion in multiple scientific fields (66). In the current experimental context, COV quantifies the variability of head kinematic parameters across all animals when the identical impulsive load is targeted. Key parameters (peak angular velocity and pulse duration) were also directly compared between skull- and machine-mounted sensors to establish the transfer of biomechanical forces, with additional regressions performed against immunohistochemistry findings to examine potential relationships with pathology. Finally, we also examined result reproducibility (65) by repeating the experiment a second time in an independent cohort of animals.
General Animal Procedures for Initial (Experiment 1) and Replication (Experiment 2) Experiments
All animal procedures were approved by our local Institutional Animal Care and Use Committee (IACUC) and the USAMRMC ORP Animal Care and Use Review Office (ACURO). The animals in both experiments were part of a larger study to examine the therapeutic effects of synthetic estrogen on a combined model of TBI and hemorrhagic shock. Sexually mature Yucatan swine were fasted but provided with ad-libitum access to water for 6–12 h prior to the experimental procedures. The animals were initially sedated with midazolam (0.5 mg/kg IM injection) and pre-medicated with buprenorphine-SR (0.12 mg/kg IM). The animals were then intubated and maintained under general anesthesia (isoflurane: 5% induction, 1–4% for maintenance combined with oxygen) with a propofol bolus (0.8–1.5 mg/kg) as needed.
In both experiments, a closed-head rotational TBI was initiated via a pneumatic actuator device (HYGE, Inc., Kittanning, PA, USA), similar to a previously described model (73). For the TBI exposure, all animals were maintained under isoflurane (1–4%), with a midazolam IV bolus (0.1–0.5 mg/kg) immediately prior to injury. Isoflurane was disconnected ~30 s prior to the TBI and immediately re-established post-injury. The animals were secured to a custom-made linkage assembly connected to the HYGE device that converts the linear motion of the piston into angular (rotational) motion. The animals' heads were secured (see Supplementary Material) to the linkage assembly through a restraint device comprising a custom-made aluminum alloy bite bar with two straps (Figure 1A). The straps were placed around the snout and bolted into the bite bar. The targeted angular peak velocity for all experiments was 250 rad/s in the coronal plane, with all animals rotated toward their right side.
Figure 1. (A) Restraint device (bite bar and straps) used in the initial and replication cohorts. (B) Representative pig skull depicting the three principal axes (red rods) as well as the placement of the skull sensor (blue cube) and plate (gray rectangle). The skull is rotated 44° along the coronal axis to match the initial starting point of the head when mounted on the restraint device in experiments 1 and 2. The skull also depicts regions of observed fractures (green outline: frontal bone; blue: orbital bone; pink: nasal bone; purple: maxilla; yellow: mandible) recorded in Table 3. (B) was adapted from University of Texas High-Resolution X-ray CT Facility (NSF IIS-0208675; http://digimorph.org/specimens/Sus_scrofa/skull/). Angular velocity traces (radians/second, rad/s) are shown for the HYGE machine sensor [(C), red trace] and the triaxial sensor [(D), coronal axis = blue trance] when affixed directly onto the bite bar. All angular velocity traces are windowed to include 4 ms of data prior to the identified rise time.
Machine kinematics were quantified via an in-house data acquisition system using an ARS-06 angular rate sensor (Applied Technologies Associates, Albuquerque, NM, USA; 25 kHz sampling frequency) that was rigidly mounted to the side arm of the HYGE device. A lightweight triaxial angular rate sensor with a small footprint (Diversified Technical Systems ARS3 PRO; 50 kHz sampling rate; 19 × 19 × 12.5 mm, 10 g) was used to directly measure head kinematics during the TBI exposure using a separate data acquisition system than the machine sensor. The sensor was positioned on an aluminum mounting plate whose inferior edge was parallel to a plane extending across the most superior aspects of the orbital sockets, with the plate mid-point located along the longitudinal suture of the skull (see the schematic in Figure 1B and Supplementary Material).
To reduce high-frequency noise, both machine and skull sensor data were smoothed with a four-pole, Butterworth filter (channel frequency class = 1,000 Hz) based on SAE-J211-1 recommendations (74). Spikes in the head sensor data were eliminated from consideration if the maximum was below 100 rad/s, the peak width was <0.4 ms, or the difference between the maximum and neighboring values was >0.3 rad/s. The highest remaining peak was selected as the peak angular velocity. A proxy for impulse duration was calculated by measuring the full width at half-maximum (FWHM) of the peak value (see Supplementary Material). Both peak angular velocity and FWHM from the resultant velocity trace were used as the primary outcome variables to capture any off-axis rotation (i.e., plane of skull near orbital sockets is sloped downward). Time-to-peak (start time defined as 5% of peak velocity) of the resultant served as a secondary outcome variable. The COV (standard deviation divided by the mean) quantified reproducibility at the methods level as has been done in previous biomedical research (66), with COV <5% defined as good, 5–10% as acceptable, and 11–20% as marginal (75, 76).
Tissue Handling and Neuropathological Evaluation
All animals underwent necropsy, including recording of gross neuropathological findings ~5 h post-injury, as well as immunohistochemistry [Supplementary Material; (77)]. Histopathology was performed on 8-μm-thick sections, focusing at the level of the head of the caudate nucleus and at the vermis of the cerebellum. Single immunohistochemistry labeling was performed to examine for extravasated serum proteins (immunoglobulin G; IgG) as markers of blood–brain barrier integrity and axonal pathology (amyloid precursor protein; APP). All sections were visualized with 3,3′-diaminobenzidine (DAB), counterstained with hematoxylin, dehydrated, and coverslipped. Both negative (no primary antibody) and positive controls were included in each experiment. The immunostained sections were imaged using an Olympus IX71 microscope.
A semi-automated process for APP N-terminus label quantification was carried out using a macro code to allow for simultaneous batch processing of all images by two independent raters separately for each hemisphere. First, the Color Deconvolution plugin in ImageJ Fiji (NIH, Bethesda, MD) was used to separate the hematoxylin stain from the DAB stain by converting the original RGB image into three eight-bit images based on the vector colors for each stain (78). The resulting DAB image was then converted to grayscale and color-inverted. A threshold, determined by calculating the intensity of the lightest APP-positive axonal bulb, was applied to the image to remove background staining and to improve interrater reliability. APP-positive counts were determined using either the original RGB image or a combination of the original RGB (examined for cellular morphology) cross-referenced with the binarized image. The ImageJ Fiji cell counter plugin was utilized to track the count per unit area (877 × 660 μm).
For IgG quantification, six images were taken adjacent to the sulcal depths at the level of the caudate nucleus in addition to six images within the cerebellum. These areas were selected based on vulnerable regions highlighted in previous literature (64) and by differences observed between positive and negative controls in pilot data (77). IgG extravasation was quantified by performing color deconvolution to separate the DAB stain from the hematoxylin stain, calculating the percentage of pixels over a consistent pre-determined background threshold and then averaging the images.
Initial Cohort (Experiment 1)
Head and machine kinematic data were successfully collected in nine of 10 attempts (178.3 ± 5.5 days old; 26.4 ± 1.4 kg; four females) during experiment 1, with the mounting plate screws failing during one procedure (bone stripping during placement). Figure 1C depicts the rotational velocity of the sensor mounted directly to the HYGE side arms, while Figure 1D depicts the rotational velocity in the coronal plane of the triaxial skull sensor when mounted directly on the bite bar (i.e., no animal). The results indicate comparable data recorded from both sensors for the coronal axis.
Figure 2A and Table 2 depict sensor recordings from the HYGE side arm, the resultant (i.e., combination of all axes) from the triaxial skull sensor, and the angular velocity trace corresponding to the coronal plane. The peak angular velocity of the resultant for the triaxial skull sensor was ~51% (t8 = 29.00, p ≤ 0.001, Morris and Deshon d = 15.44) of the magnitude of the HYGE sensor (Figure 2A), with an 8-fold increase in COV (Table 2). The latter was a function of both reduced mean and higher standard deviation (Table 2). A metric of impulse duration (FWHM) from the skull sensor data was significantly (t8 = −12.06, p ≤ 0.001, d = −4.39) greater (~91%) than the mean value calculated from the HYGE sensor data. The mean time-to-peak was not statistically different (p = 0.09) between the HYGE and the skull sensor data. The comparisons between HYGE and skull sensor recordings in the plane approximating the coronal axis are presented in Supplementary Material.
Figure 2. (A) Average angular velocity traces (radians per second: rad/s) for experiment (Exp) 1 collected with the HYGE machine sensor (left column; red trace) and triaxial skull sensor (right column; resultant: green trace; coronal axis: blue trace; sagittal axis: purple trace; axial axis: orange trace) in the initial testing cohort (N = 9). Off-color shaded bands represent the standard error of the mean for each trace. All angular velocity traces are windowed to include 4 ms of data prior to the identified rise time. (B) Plotted data for replication cohort (Exp 2; N = 4) machine and skull sensors using an identical scheme. (C) Box and scatter plots (Exp 1; red diamonds) or scatter plots (Exp 2; teal diamonds) for peak velocity, full width at half-maximum of the impulse based on peak, and time to peak. Data are plotted separately for the resultant and the coronal axis of the skull sensor data.
Table 2. Key parameter results for initial testing (experiment 1) and replication (experiment 2) cohorts.
The next series of analyses compared skull sensor recordings for the resultant motion relative to the plane approximating the coronal axis. The largest difference was observed for FWHM (t8 = −9.96, p ≤ 0.001, d = −2.69), with the resultant exhibiting a longer impulse duration, most likely indicative of multiplanar movement. This can be further confirmed through an examination of the right column of Figure 2A. Consistent multiplanar motion is present in both axes, corresponding with the absolute magnitude of rotational velocity in the sagittal (54.7 ± 14.5 rad/s) and axial (62.6 ± 11.2 rad/s) planes. This multiplanar motion occurred following the peak angular velocity in the coronal plane (see Supplementary Figure 1A for individual sensor data on three randomly selected animals from experiment 1, which further confirms the relatively consistent pattern of head kinematics). Supplementary Video 1 further illustrates the average total angular excursion over time in the three rotation planes.
The resultant motion was also associated with a small but significant (t8 = −2.48, p = 0.03, d = −0.15) increase in angular velocity relative to the coronal axis. The time to peak was also significantly higher (t8 = −6.00, p ≤ 0.001, d = −1.11) for the resultant relative to coronal plane, although the COVs were roughly similar. Both of these results are expected due to the algorithmic calculation of the resultant (i.e., root mean square summing).
Gross necropsy indicated that all animals in experiment 1 exhibited maxillofacial fractures (herein defined as nasal, frontal, orbit, and mandible bones in the swine) of varying complexity (Table 3). Two animals had fractures that were limited to the left nasal bones only, whereas the other seven animals had more complex fractures that included the left nasal, frontal, and orbit bones. In addition, a right mandible fracture was observed in six animals. Six animals exhibited hemorrhage on the ventral surface of the brain, with one animal also demonstrating hemorrhage that extended from the frontal to the parietal lobes along the longitudinal fissure.
Table 3. Fracture distributions for the initial (experiment 1) cohort.
Replication Cohort (Experiment 2)
Four Yucatan (185.3 ± 10.5 days old; 25.5 ± 1.3 kg) male swine comprised the replication cohort. Figure 2B and Table 2 depict sensor recordings from the HYGE side arm and skull sensor data. All primary results from experiment 1 were replicated, even with the smaller sample size. Specifically, a 46.9% reduction in peak angular velocity magnitude (t3 = −17.58, p ≤ 0.001, d = −13.35; Figure 2B) and a significantly increased (86.2%) FWHM (t3 = 16.84, p ≤ 0.001, d = 5.37) for the triaxial skull sensor resultant were observed relative to the HYGE sensor (Table 2). Similar to previous findings, the COV was also higher for the skull sensor compared to the HYGE sensor (Table 2). Mean time-to-peak was not statistically different between the HYGE and skull sensor data, with a moderate effect size (p = 0.72; r = −0.13).
Uncorrected one-vs.-many t-tests confirmed that the peak angular velocity (p range = 0.08–0.23), FWHM (p range = 0.12–0.35), and time to peak (p range = 0.06–0.14) for each animal in experiment 2 were statistically similar to those in experiment 1 (Figure 2C; i.e., reproducibility at the single-subject level). The one-vs.-many t-tests were not corrected to provide a more liberal threshold for the determination of replication for non-significance. The FWHM for the resultant was also significantly larger than the coronal plane axis (t3 = 13.19, p = 0.001, d = 5.88), suggestive of a longer impulse duration (54.3% increase), potentially secondary to multiplanar movement. Specifically, a pattern of consistent magnitudes for the angular velocity components was again present in sagittal (56.3 ± 16.6 rad/s) and axial (54.2 ± 4.4 rad/s) planes (right column of Figure 2B), which temporally corresponded with the peak angular velocity in the coronal plane (see Supplementary Figure 1B for individual experiment 2 animal data).
Similar to experiment 1, gross necropsy indicated that all animals exhibited maxillofacial fractures of varying complexity, which were limited to the left side in all but one animal. Additionally, one animal presented with a right mandible fracture. All four animals exhibited varying degrees of hemorrhage, which was present for the most part on the ventral surface of the brain.
Necropsy Findings and Correlation With Pathology
Please see Supplementary Material for interrater reliability results and methods comparisons for experiment 1. Multifocal axonal pathology, characterized by accumulations of APP-positive axonal beads or varicosities, was observed throughout the periventricular section at 5 h post-injury, with the largest accumulation of pathology surrounding the dorsolateral tip of the lateral ventricles (Figure 3A). In contrast, there was minimal evidence of diffuse axonal injury in the vermis of the cerebellum (Figure 3B). IgG extravasation was observed in the depth of the sulci for 9/13 animals and in the vermis of the cerebellum for 11/13 animals (Figures 3C,D).
Figure 3. Immunohistochemistry results from, respectively, the periventricular region at the level of the caudate nucleus (A) and at the vermis of the cerebellum for amyloid precursor protein (B) for selected animals from the initial testing cohort (experiment 1). Periventricular region (C) and vermis of cerebellum (D): present data from immunoglobulin G (IgG) antibodies. The results indicated robust evidence of blood–brain barrier breach (IgG) in both the periventricular region and cerebellum, whereas diffuse axonal injury was limited to the cortical and periventricular regions at ~5 h post-injury.
Given the strong evidence for replication, data were combined across experiments 1 and 2 to determine the potential biological relevance of kinematics in relation to immunohistochemistry findings. Specifically, independent multiple-regression models were used to determine whether the primary measures of angular velocity (peak magnitude and FWHM) from either the HYGE (model 1) or resultant from the skull sensor (model 2) were associated with immunohistochemical evidence of diffuse axonal injury (APP; cross-hemisphere) or blood–brain barrier disruption (IgG; periventricular and cerebellum) across all animals in experiments 1 and 2 (N = 13). However, the omnibus tests for all six models were null (p's ≥ 0.21). The correlation coefficients between head kinematics and IHC findings demonstrated medium effect sizes (APP Pearson's r = 0.41; IgG r = 0.30), suggesting that larger sample sizes would be necessary to detect significant differences in cellular pathology.
Relationship Between Machine and Skull Sensors
Finally, correlation analyses examined the relationship between the skull sensor resultant motion and HYGE sensor data combined across experiments 1 and 2. There was minimal correlation between the HYGE and skull sensor measurements for peak angular velocity (Pearson's r = −0.23; p = 0.45), FWHM (r = 0.44; p = 0.14), or time to peak (r = 0.23; p = 0.45).
Rapid acceleration/deceleration of the head is potentially the most common factor in human brain trauma (1, 68). However, to date, only five other acceleration studies have mounted sensors directly to the head to quantify potential differences between machine and head kinematics (5–9), and no studies have examined reproducibility. Sano et al. (5) used a gravitational model (free fall from various heights) to induce injury in helmeted and unhelmeted primates, reporting peak linear accelerations of 28–230 g. Masuzawa et al. (8) reported linear accelerations of the head, ranging from 349 to 591 g, and verified with high-speed cameras that there was minimal rotational movement (angular velocity not measured). Ommaya et al. (9) and Kanda et al. (7) used a linear impactor to strike the head of an unrestrained primate, reporting linear head accelerations of up to 869 g (Ommaya) and 830 g (Kanda) and angular velocities of 52–510 rad/s (Kanda). In contrast, the sheep model of Anderson et al. (6) resulted in higher linear accelerations (714–1,835 g) but relatively lower angular velocities (39–118 rad/s), which were attributed to the use of a modified captive bolt gun with higher velocities than the linear impactor of Kanda et al. (7).
The reproducibility of head kinematics has not been examined at either the methodological (individual subjects) or results (across experiments 1 and 2) level for any large animal acceleration model (65). Current results indicate "good" method reproducibility for peak angular velocity (COV = 1.1%) and duration (FWHM COV = 2.5%) for machine kinematics, with exceptional targeting of the desired peak velocity (250.68 ± 2.88 rad/s). However, the mean angular velocity for head kinematics was approximately half of the machine and occurred over a duration that was approximately twice as great. The method reproducibility for these key head kinematic parameters ranged between 8 and 12%, with higher COVs observed for the secondary time-to-peak variable. Critically, the COV produced from the head kinematics data can still be classified in the acceptable or low marginal range based on previous biomechanical models and other biomedical fields (75, 76). There was no statistical relationship between the magnitude of the machine and skull sensor recordings when data were collapsed across experiments, which was likely a result of the extremely high reproducibility from the machine sensor and thus limited variance.
Most dynamic non-impact acceleration models assume that biomechanical forces are limited to a single plane (73), with the plane of rotation influencing clinical (i.e., loss of consciousness) and pathological (i.e., number of hematomas) outcomes in a species-dependent fashion (12, 62). Head kinematics, in the current study, exhibited a complex but relatively consistent pattern of multiplanar motion across both initial and replication cohorts. Specifically, more complex, multiplanar head motion occurred at angular velocities of 50–65 rad/s in both the axial and sagittal planes following the rapid deceleration of the head in the coronal plane. The multiplanar motion was primarily observed as the magnitude of angular velocity declined in the coronal plane, suggesting that it occurred after the snout was fully loaded against the straps. Previous HYGE studies have typically targeted head angular velocities approximately double those observed in the current experiment when principally rotating in the axial (e.g., 142–171 rad/s) or sagittal (e.g., 80–159 rad/s) plane [Table 1; (2, 39, 49, 51)]. However, these previous measurements were obtained from machine-affixed rather than skull sensors. It is therefore difficult to ascertain the biological impact of the multiplanar motion observed in the current study.
Factors related to animal morphometry, biomechanical properties, animal positioning, and/or construction of the restraint device potentially contributed to the observed differences between machine and head kinematics (magnitude and COV). The ratio of head-to-body mass differs among large animals as a function of age (2), species (sheep vs. swine), and strain [Yorkshire vs. Yucatan; (79)], with age and brain mass interacting in a complex fashion to produce axonal injury (2). The width and the length of the snout also likely affect the transfer of energy between the restraint device and the head. Genetically controlling for morphological differences (e.g., snout or head size) is not likely to be economically feasible in large animal models, with genetic modifications also resulting in other unintended consequences observed in other species (80).
Immunohistochemical evidence of diffuse axonal injury (periventricular region only) and blood–brain barrier breach (both periventricular and cerebellar regions) was observed in the initial cohort, replicating previous results observed with this hypovolemic polytrauma injury model (77) as well as multiple previous acceleration models (see Table 1). These two pathologies have been co-localized in other swine rapid acceleration studies using immunoenzymatic double-labeling techniques (64), and the breakdown of the blood–brain barrier (81) may further stimulate the cleavage of APP to release toxic species of Aβ (82). Previous studies have reported associations between immunohistochemically measured diffuse axonal injury and head kinematics (2, 6). However, these studies intentionally varied head kinematics either experimentally (6) or through retrospective data analyses (2), purposefully employing a much larger range of putative inertial load (i.e., measured at the machine level). Additional differences in sample size and statistical power (N = 49 in Atlan [2] vs. N = 13 in the current study) are also present across experiments. In contrast, a primary focus of experiments 1 and 2 was to examine reproducibility and thus minimize injury variation (e.g., a targeted machine exposure of 250 rad/s in coronal plane for all animals). With these caveats in mind, the current results indicate that the variations observed in head kinematics in the current experiment were not of sufficient magnitude to capture any differences in diffuse axonal injury or blood–brain barrier breach as measured through immunohistochemistry.
Historically, non-impact acceleration models have been characterized by whiplash injury caused by non-cranial strikes (10, 11) and sled crashes (8) or by attaching a helmeted head to the HYGE actuator (12, 13). During the current implementation of the HYGE model, all animals from the initial and replication cohorts exhibited a stereotypical maxillofacial fracture pattern that included the left nasal bones, which sometimes extended bilaterally, or into the orbits. A subset of animals also experienced fractures of the right mandible. The coronal rotation always occurred to the right side of the animal, such that the initial impulsive loading forces from the bite bar (see Figure 1) would maximally impact on the left upper palette/snout and right mandible prior to the rotation of the neurocranium, providing a close correspondence with the observed pattern of maxillofacial fractures. Future studies are required to more carefully delineate which individual or combination of factors principally affects the transfer of biomechanical force between the machine and head. Potential candidates include slippage from the device during the initialization of the injury or the dispersing of energy into maxillofacial structures resulting in fractures.
As previously mentioned, a strength and limitation of the current study was that the experimental procedures were carefully controlled. This is a necessary step to establish reproducibility but limits the generalization of results to the specific experimental methods studied herein. Critically, the transfer function for biomechanical forces between HYGE machine and head may vary based on the initial impulsive loading parameters (e.g., 125 vs. 250 rad/s) and primary plane of rotation (e.g., coronal vs. axial). The financial cost of a series of these experiments would be very high, representing a limitation of any large animal model. Several other limitations to the current study should be noted. First, individual differences in skull morphometry restricted the placement of animals in plumb/identical positions within the restraint device as well as for the placement of the sensor. This limitation is partially mitigated by the consistent head kinematics exhibited by all animals in both the initial and replication cohorts on a group and individual level (see the plots in Supplementary Figure 1) as well as our utilization of the resultant to characterize head kinematics. Second, the current placement of the sensor measured kinematics of the skull rather than the brain, with skull–brain kinematics potentially becoming decoupled during complex trauma (2, 83). Third, only male animals were utilized in the replication experiment, precluding the full generalization of the results to both biological sexes.
In summary, initial impulsive loading parameters such as angular velocity are often used in computational models to predict underlying deformations of brain tissue and the subsequent expression of pathology (2, 3, 28, 83–85). Determining the reproducibility of experienced head kinematics in large animal models is therefore critical for future therapeutic trials seeking to realistically model human trauma in animal surrogates (1, 69). Current results indicate that, for a target peak angular velocity of 250 rad/s in the coronal plane, key head kinematic parameters (angular velocity magnitude and duration) significantly differ from the initial loading conditions produced by the HYGE machine. However, the reproducibility of key head kinematics is generally within acceptable ranges (75, 76). Future studies are necessary to determine if similar results are observed for sagittal and axial rotations using the HYGE device at different angular velocities (2) as well as how other experimental factors (animal weight, body positioning, modifications to the restraint device, etc.) affect the transfer of biomechanical forces between the machine and the head.
The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.
The animal study was reviewed and approved by the USAMRMC ORP Animal Care and Use Review Office and Lovelace Biomedical Research Institute's local Institutional Animal Care and Use Committee.
AM and RK designed and conceptualized study and aided in collection and analysis of the data. JL wrote the software used to interface with data collection sensors and aided in collection. AD, JR-L, and RD collected, curated, and analyzed data. JL, DS, SP, CR-B, and CM curated and analyzed data. AD and DS performed visualization for figures, tables, and video. AG and MV aided in data collection. AM, JL, AD, DS, RD, CM, SP, and CR-B performed the initial draft of the manuscript. DP, DC, VJ, AG, TM, MV, DS, and RK revised the manuscript for intellectual content and, along with all other authors, approved the final version of the manuscript. All authors contributed to the article and approved the submitted version.
This research was supported by a grant from the Department of Defense (W81XWH-17-2-0052) to AM. Histological analysis was performed by the Preclinical Core Facility at the University of New Mexico Center for Brain Recovery and Repair, which was supported by an Institutional Development Award (IDeA) from the National Institute of General Medical Sciences of the National Institutes of Health under grant number P20GM109089.
We would also like to thank Mandy Pacheco, Fawn Reed, Sheila Alonzo, Jaime Leo, and Jimmy Gonzales for their help with data collection.
The Supplementary Material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fneur.2021.658461/full#supplementary-material
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Keywords: traumatic brain injury, large animal model, dynamic acceleration, head kinematics, sensors, diffuse axonal injuries
Citation: Mayer AR, Ling JM, Dodd AB, Rannou-Latella JG, Stephenson DD, Dodd RJ, Mehos CJ, Patton DA, Cullen DK, Johnson VE, Pabbathi Reddy S, Robertson-Benta CR, Gigliotti AP, Meier TB, Vermillion MS, Smith DH and Kinsler R (2021) Reproducibility and Characterization of Head Kinematics During a Large Animal Acceleration Model of Traumatic Brain Injury. Front. Neurol. 12:658461. doi: 10.3389/fneur.2021.658461
Received: 25 January 2021; Accepted: 03 May 2021;
Ibolja Cernak, Mercer University School of Medicine, United States
Ginu Unnikrishnan, Intelligent Automation, United States
Tim Harrigan, Johns Hopkins University, United States
King Yang, Wayne State University, United States
Copyright © 2021 Mayer, Ling, Dodd, Rannou-Latella, Stephenson, Dodd, Mehos, Patton, Cullen, Johnson, Pabbathi Reddy, Robertson-Benta, Gigliotti, Meier, Vermillion, Smith and Kinsler. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
*Correspondence: Andrew R. Mayer, amayer@mrn.org


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						$this->session->set_flashdata('message_error_left','Data tidak berhasil di tambah');
					}
				}else{
					$this->session->set_flashdata('message_error_left','Password yang dimasukkan belum sama.');
				}
				redirect('user');
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	{
		if ($this->uri->segment(3)!="")
		{
			$username = $this->uri->segment(3);
			$result['user'] = $this->user_model->selectById($username);
			header('Content-Type: application/json');
			echo json_encode($result);
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redpajama_set_name: RedPajamaGithub


Katniss Everdeen prepares for the reaping for the Hunger Games, a game watched on live television where one boy and one girl from each district who are twelve to eighteen years old are forced to participate to battle to the death until one person remains in an arena created by the Gamemakers. Primrose, Katniss' sister, is chosen as the female tribute for the Hunger Games. Katniss volunteers to replace Primrose in the games, and Peeta Mellark is selected as the male tribute which upsets Katniss, because he gave her free loaves of bread when her family was about to die of starvation a few years ago, so she would have a hard time killing him in the arena. They are transported to the Capitol in a train, and then they are prepared for the interview before the Hunger Games. The day after the interview, the Hunger Games start, and the twenty-four tributes are sent to the arena. Many are killed on the first day, but Katniss survives along with Peeta and eleven others. She encounters many situations that put her life on the line, but she survives. Soon, she realizes that the Hunger Games is not the only thing that may kill her.
Once I started to read this book, I found it hard to stop and close the book. The plot is fast-paced, and there is never a moment in the book where you question yourself about reading the book. The Hunger Games has strong vocabulary that is well-suited for eighth grade. It is hard for me to connect to this book, since I was never in a life-threatening situation or a time when a member of my family was about to be taken away from me. Some parts of the book are very unexpected, and it shapes the story in a unique way. I have never read a book similar to this, so The Hunger Games interested me. It is a popular book so I decided to try the book. I would recommend this book for people ages thirteen to eighteen because of the violence and the romance. I would rate this book ten out of ten stars.
1. Why does Katniss take Primrose's place in the Hunger Games?
2. Why did Katniss think that the odds were not in her favor when Peeta Mellark was chosen as the male tribute?
3. What does Katniss wear from her district to the arena?
4. Why does Katniss not trust her mother?
5. Why does Katniss shoot towards the Gamemakers in her private session?
6. Why is Katniss angry at Peeta after the interview?
7. What is Katniss' first problem after the Hunger Games start and she leaves the Cornucopia?
8. How does Katniss kill Glimmer and a girl from District 2?
9. Why does Katniss want Rue for an ally?
10. How does Katniss destroy the Careers' supplies?
11. What is the hidden message in the gift that Haymitch sends to Katniss?
12. How is Katniss able to go to the fest to get Peeta the cure for his wound even though Peeta objects?
13. Why does Thresh decide to not kill Katniss during the feast?
14. Why is the interview after the Hunger Games the most dangerous part of the games?
15. How come the Capitol did not like it when Katniss and Peeta were about to eat the poisonous berries so that there would be no victor for the Hunger Games?


text:
Marie Brand und das Erbe der Olga Lenau ist die vierzehnte Episode der Krimiserie Marie Brand. Der Fernsehfilm mit Mariele Millowitsch als Kriminalhauptkommissarin Marie Brand und Hinnerk Schönemann als Kriminalhauptkommissar Jürgen Simmel wurde am 21. Januar 2015 erstmals im ZDF ausgestrahlt.

Handlung
Hannah Lenau, eine junge Künstlerin, stellt auf ihrer ersten Vernissage großformatige Collagen aus. Sie verarbeitet darin die Hausbesetzerszene der 1970er und 1980er Jahre, zu der einst ihre Mutter Olga gehörte und von der sie auch einen Großteil der Fotos dazu erhalten hatte. Während sie auf das Eintreffen ihrer Mutter wartet, stürzt diese allerdings aus dem Fenster ihrer Altbauwohnung. Marie Brand und Jürgen Simmel sollen den Fall übernehmen und Marie findet schnell heraus, dass die Frau gestoßen wurde und nicht freiwillig den Tod gesucht hat. Sie wohnte wie vor vierzig Jahren noch immer in einer WG und war auch noch politisch aktiv. Laut ihres Testaments soll die Wohnung, die Olga gehörte, nach ihrem Tod in eine Stiftung übergehen und als WG mit stets vier Personen erhalten bleiben. Simmel verdächtigt Harald Wecker, eines der WG-Mitglieder, da das Verhältnis der vier untereinander in letzter Zeit nicht sehr harmonisch war. Brand findet indes fremde Fingerabdrücke an einem Glas, was auf einen unbekannten Besucher schließen lässt. Schnell können sie die Spuren dem Bauunternehmer Bernd Lüttke zuordnen, mit dem sich das Opfer in letzter Zeit massiv auseinandergesetzt hatte. Er bestreitet, Olga etwas angetan zu haben, und Brand hält ihn für glaubwürdig.

Unerwartet wird in Hannah Lenaus Atelier eingebrochen und alle Reserve-Fotos ihrer Ausstellung sind danach verschwunden. Glücklicherweise hat sie aber alle digital in einer Cloud gespeichert, sodass sie nicht ganz verloren sind. Marie Brand versucht, über die Fotos eine Spur zu dem Mörder zu finden. Doch ehe sie irgendeinen Hinweis entdecken kann, wird der Kleinkriminelle Nils Schmadtke erschossen aufgefunden. Alle Zeichen deuten darauf, dass er in das Atelier eingebrochen ist und nun von seinem Auftraggeber zum Schweigen gebracht wurde.

Marie Brand stößt bei ihren Ermittlungen auf den Todesfall eines Polizisten, der vor dreißig Jahren bei einer Hausbesetzung, die Olga organisiert hatte, ums Leben kam. Daher geht sie zusammen mit Simmel dieser Spur nach, die zu dem ehemaligen Polizeipräsidenten Artus Matthiesen führt. Die Ermittler finden heraus, dass Matthiesen Ermittlungsunterlagen manipuliert hatte. Ganz offensichtlich wollte er seinen unehelichen Sohn schützen, bei dem es sich, wie sich im Zuge der Ermittlungen herausstellt, um Harald Wecker handelt. Er hatte seinerzeit im Handgemenge den tödlichen Schuss auf den Polizisten abgegeben und Matthiesen wollte das vertuschen. Dass ihn nun nach so vielen Jahren die Problematik wieder einholen könnte, hatte er nicht gedacht. Er gibt zu, dass Olga ihm Karten hatte zukommen lassen, damit er sich die Ausstellung ansieht. Als er die Fotos mit den Szenen der damaligen Hausbesetzung sah, sei er umgehend zu Olga gefahren. Sie wollte ihn erpressen, so wie sie es schon einige Male getan hatte, und er wollte, dass damit nun endlich einmal Schluss ist. Den Mord an dem Einbrecher gibt er ebenfalls zu und wird daraufhin festgenommen.

Hintergrund
Die Folge wurde von der Eyeworks Germany GmbH, Köln, produziert und in Köln und Umgebung gedreht. In Italien soll der Film unter dem Titel Marie Brand e l'amore che non perdona ausgestrahlt werden.

Rezeption

Einschaltquoten
Der Fernsehfilm Marie Brand und das Erbe der Olga Lenau erreichte bei seiner Erstausstrahlung im ZDF am 21. Januar 2015 durchschnittlich 6,43 Millionen Zuschauer, was 20,2 Prozent des Marktanteils in Deutschland entspricht.

Kritiken
Volker Bergmeister von tittelbach.tv urteilt: "Schauspielerisch weiß neben den beiden Kommissaren insbesondere Peter Davor zu überzeugen. Der gibt – wie so oft – einen Gefallenen und Gezeichneten des Lebens. Den hat er gut drauf, wenngleich diese Typen-Psychologie schon ein wenig abgenutzt erscheint. Das gilt auch für den Krimi-Plot von 'Marie Brand und das Erbe der Olga Lenau'. Und so ist dieser 14. Fall der Kölner unterm Strich nicht mehr als nette, kurzweilige Krimiunterhaltung. Das ZDF weiß offenbar, weshalb Marie Brand am Mittwoch (lief auch schon donnerstags) ermittelt, für einen Samstagskrimi reicht die Qualität nicht ganz."

Die Kritiker der Fernsehzeitschrift TV Spielfilm geben den Daumen nach oben für viel Spannung und Humor und meinen zu diesem neuen Marie-Brand-Film: "Brand und Simmel, die hier zeitweise zusammenwohnen, amüsieren mit trockenen Dialogen über WG-Tauglichkeit. Fazit: Marie und Jürgen: eine nette Ermittler-WG."

Sidney Schering  bei Quotenmeter.de kommt zu dem Urteil: "Die Sprüche sitzen, auch in den weniger pointierten, gemeinsamen Szenen stimmt die Chemie zwischen den Mimen sowie ihren Figuren – daher nimmt auch die etwas konstruierte Spurensuche stellenweise amüsante Formen an. Dennoch holt der grundsolide inszenierte Film nicht das volle Potential aus Brand und Simmel heraus. Andererseits: Die Erlebnisse der ungleichen Ermittler wurden auch bereits träger und belangloser dargeboten als hier. Für Freunde der Reihe ist 'Marie Brand und das Erbe der Olga Lenau' also ganz adäquate Krimiunterhaltung. Novizen wiederum hätten schon bessere Ausgaben treffen können."

Bei der Osnabrücker Zeitung urteilt Tom Heise: "Marie Brand und ihr Partner Jürgen Simmel sind ein starkes Team, die ihnen offerierten Fälle überzeugen hingegen weniger. […]  Auch wenn sich der Krimi einem politisch links orientierten Personal widmet, bleibt er unpolitisch. Und leider auch ein wenig langatmig. Schade, denn die Reihe hätte das Potenzial zum ganz großen Wurf. Vielleicht beim nächsten Mal."

Weblinks

 Marie Brand und das Erbe der Olga Lenau bei fernsehserien.de

Einzelnachweise

Filmtitel 2015
Deutscher Film
Erbe der Olga Lenau #Marie Brand und das

redpajama_set_name: RedPajamaWikipedia


text:
Penguin Putnam
As a New England mother struggles to support her family in the wake of her husband's service in the Civil War, her four daughters struggle, too—caught between childhood dreams and the realities of burgeoning adulthood. For Meg, Jo, Beth, and Amy March, raised in integrity and virtue, negotiating the right path in life means making choices that will either narrow or expand their destinies.
Based on the author's life, Little Women transcends genre, gender, and class with its examination of personal quests, societal restrictions, family ties, and the end of innocence.
>"Let us be elegant or die!"
I'd like to confess up front, I avoided reading this book for most of my life simply because of the title. It sounded so… painfully feminine. And as someone who's struggled to make peace with their biological gender, I felt some sort of misplaced obligation to resist exposure to something that could so clearly hold no interest for me.
I was horrendously mistaken.
This is a sweeping family drama, set during the American Civil War. Languidly paced and often treading on the poetic side, it centers on the March family—specifically on the four young sisters who are all close in age—as they grow up throughout the book. There's Meg, the kind and responsible eldest; Josephine, our tomboy protagonist (who happens to be based semi-autobiographically on the author herself); Beth, the quiet and virtuous; and Amy, the somewhat vain and more shallow-minded youngest of the four sisters. Their family is somewhat poor, and girls spend a good deal of their childhood coming up with interesting and artful methods of amusing/distracting themselves while their minister father goes off to serve Union soldiers as a chaplain.
I'm not really doing the characters any justice here, but it's their growth, development, and chemistry that largely, and successfully, drove the narrative. There are undercurrents of empathy-building, imaginative fancy, gratefulness and optimism in the face of trials, along with a coming-of-age element experienced across several very different personalities within the same family unit.
For obvious reasons, I connected with the character of Jo from the very beginning. While the era, being what it was, would have made it particularly difficult to be a more independent and masculine-bent female, Jo had the benefit of the unconditional love and support of her family. Perhaps most significantly, she had an encouraging father who at no point made her feel limited by (or inferior on account of) her sex. Her struggle with herself, the world's stifling expectations, and her own goals, is something most readers may be able to relate to.
"I keep turning over new leaves, and spoiling them, as I used to spoil my copybooks; and I make so many beginnings there never will be an end."
As a part of my needless resistance to this classic, I decided to listen to this one in audio book. I don't regret that move. This particular narrator (Andrea Emmes) did a masterful (mistressful?) job of bringing the cast to life. With four sisters as main characters, I was concerned about not being able to tell voices apart. But Emmes made the experience into more of a richly layered auditory play than a simple reading.
Favorite Quotes:
*"I'd rather take coffee than compliments just now."
* "There are many Beths in the world, shy and quiet, sitting in corners till needed, and living for others so cheerfully that no one sees the sacrifices till the little cricket on the hearth stops chirping, and the sweet, sunshiny presence vanishes, leaving silence and shadow behind."
Angela Blount, Staff Reviewer Top 50 Reviewer 272 reviews
View all user reviews View most helpful
Curl Up With A Classic
I read and re-read my copy of The Little Women so many times as a girl, the cover fell off. The book is a lovely treasure trove of family relationships, growing up, romance, and learning how to celebrate even during the pain that sometimes happens in life. Alcott has an unassuming story-teller style of writing that immediately ushers the reader into the heart of the characters and makes you feel part of the family. I can't recommend it enough.
CJ Redwine, Site and Staff Manager Top 10 Reviewer 406 reviews
Classic Girl Story
"Christmas won't be Christmas without any presents."
Everyone is no doubt familiar this opening line. It comes from Little Women, the beloved classic of the four young March girls. Meet sixteen-year-old Meg, the plump and matronly oldest sister; Jo, the awkward and rambunctious tomboy; Amy, the spoiled and artistic blond; and Beth, the quiet and reserved youngest sister. With their father away at war, the girls grow up under the watchful eye of Marmee.
Of course, the March family is not perfect, which is why we love them. Meg succumbs to vanity a party when she borrows a dress that is far too stiff with a train that is far too long. She also fears during dances that her earrings will fall off. Jo refuses to forgive her sister Amy for an act of vengeance, until a skating disaster reunites them. Amy receives the strap at school for ignoring a rule about candy. And Beth loses a beloved bird during a disastrous week when the girls experiment with idleness. Even the one who most often instills moral guidance, Mrs. March, admits that it's taken her over forty years to only partially cure her anger.
While the entire family is creative, Jo is the writer amongst them. This is my main reason for liking her best. We're both always reading. Jo likes to receive books as presents, is most attracted to homes where the owners have libraries, and typically cites examples from literature to prove her points. We're also both always writing. Jo writes plays and contributes news to the family newsletter. She loves sharing stories about what happens in her life. I also most identify with her habit of getting herself into scrapes.
Despite the absence of their father, the family is close knit. The Marches sing together. They help the needy, even to the point of giving up their Christmas breakfast to help a starving family. Not being rich themselves, they produce their own plays and a family newspaper for entertainment. Under the moral direction of their mother, they also learn many life lessons. I embraced many of the principles myself such as refusing to let the sun go down on my anger. Little Women continues to be one of my favorite girl books.
Allison Top 500 Reviewer 19 reviews
Reader reviewed by Sarima89
This is one of the most special books for me. It was the first one I read. The one that made me a booklover, and for that it has a very special place in my heart.
This is a tocuhing story, a beautiful book, beautifully written. The story of a family, going thru a lot of things, good and bad things, and they always support each other and know how to look at the bright side.
Is really good, you will enjoy it no matter how many times you read it.
a reader #1 Reviewer 19911 reviews
Well Deserving of Its Classic Status
Reader reviewed by Stephanie
The four March sisterswarm and fashionable Meg, literary and tomboyish Jo, frail and angelic Beth, and lovely but vain Amylive in Civil War New England. With their father off to war, they grow and learn to be better women under the ever-patient guide of their mothers hand. Lessons in humility, romance, friendship, loss, and joy occur to the March sisters in a variety of scenarios which have been pleasingly narrated for us by the character-writer Alcott. Never dull, and full of important morals and fun, it is no wonder that LITTLE WOMEN remains a beloved classic over a century after it was first published.
Classic!
Reader reviewed by Kit-Kat
Though this book was written in the 1800's, a lot of the content still applies today.
The characters are individual and comical, and you learn to love them. The plot is funny, with a few unexpected twists.
The book is simple, but sweet, and teaches important values.
Dont know about you...
Reader reviewed by joanne
I don't know about you, but I thought Little Women was fantastic. I'v read it a million times...and yes, my opinion has changed. When I first read it, I still thought it was great, but I didn't understand parts of it, and was a bit dissapointed with the ending. When I read it a second and third time, though, I got to apprieciate the whole meaning of the story. Personally, I thought it was a touching story of a loving family...I loved the characters, the closeness of the friends and families; a beautiful, timeless classic.
Over-rated, really...
Reader reviewed by Ally
I appreciate that this book is a classic, but it didn't sit too well with me. It would have been better to read it in the time period it was written. The characters were pretty nerve-racking, and the plot was a tad thin. Also, I was annoyed by the constant reminders of a womans supposed place. Beautifully written, but very over-rated.
Reader reviewed by Jessica M.
Little Women is considered one of the greatest American classics of all time. I thought so too, because it tells the life stories of four sisters growing up in 19th century America. It is kind of like The Sisterhood of the Traveling Pants in a way, because in the 2nd part of the novel, each chapter tells about one of the girls. I liked reading about the four March sisters, Meg, Jo, Beth (wish she didn't die), and Amy. I read this book when I was 9, but didn't know its true meaning until I read it again. This book is one of the greatest girl books of all time!
Disapointed Hearts
Reader reviewed by Aimee
This was a surprising book full of laughs and tears just like any good book ought to have. Jo was confused in love, and she suffered a loss of her unguided acts. But as we al do, she moved on. And although I was disapointed in the ending, I think everyone who has read this book will agree -- it is the most colorful book a reader could ask for.
Till Next Time -Aimee
Jo is a FOOL! But other than that, it's a really good book
Reader reviewed by FlooCrookshanks
Unfortunately due to a revealing Friends episode (you know the one I mean!), I knew half of the main things that happened in this book before I even picked it up. However, it's beautifully written and easy to read and understand - unlike a lot of classics, which are so garbled it's no wonder you have to study them at school to understand them.
The book has two parts, and I must say, I loved the first part with a dozen passions. The second part was disappointment after disappointment - not because it was bad, don't get me wrong - but as in life, things don't always turn out the way you want them to.
This story will most likely make you smile, sob, and want to tear out specific pages in the hope it would stop certain things from happening. Were I to read it again, I'd read it only halfway and then just pretend everything ended the way I wanted it to. ;)
Four sisters and their mother have to deal with their father being away at war. Meanwhile they meet friends and love interests, grow up and deal with the trials and tribulations of life, and learn to become better people. Marriage proposals, arguments, jobs, illness and heartache are but a few of the things they are forced to deal with, but no matter what, they never stop loving one another.
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redpajama_set_name: RedPajamaCommonCrawl


text:
Indenfor telekommunikation, er multipleksing (MUX-ing) det at kombinere to eller flere informationskanaler i en fælles transmissionsmedium ved at anvende hardware kaldet en multiplekser (eller MUX). Det modsatte af dette er kendt som demultipleksing (DEMUX) eller inverteret multipleksing.

George O. Squier (1863–1934) opfandt princippet i 1910 ved at anvende en bærebølgefrekvens til at kombinere flere telefonsignaler i én telefonlinje.

I elektrisk datakommunikation, er de to basisformer af multipleksing tidsdelt multipleksing (TDM)) og frekvensdelt multipleksing (FDM). Indenfor optisk kommunikation kaldes analog FDM bølgelængdemultipleksing, ofte omtalt med den engelske betegnelse wavelength division multiplexing (WDM).

Indenfor kodning af videosignaler er multipleksing processen at kombinere flere video-, lyd- og/eller billedstrømme i en signalstrøm. Det modsatte af dette, at dele strømmene ind i sine oprindelige separate signalstrømme, kaldes demultipleksing.

Indenfor spektroskopi er udtrykket anvendt i en sammenhæng til at indikere at et eksperiment er udført med en blanding af flere frekvenser på en gang – og at resultatet blev afdækket ved anvendelse af Fouriertransformation.

Kilder/referencer
 Federal Standard 1037C

Telekommunikation
Radio
Spektroskopi


text:
Home » centerfold » A Very Happy Accident: FireFly Farms' MountainTop Bleu
A Very Happy Accident: FireFly Farms' MountainTop Bleu
Leigh Belanger and Photographer Callie Lindsey | June 22, 2017
A Very Happy Accident is featured in our Summer 2017 issue.
Accident, a town of 320 people in Garrett County, occupies a rough triangle of land in the westernmost corner of Maryland. Though within striking distance of Baltimore, Pittsburgh, Philadelphia, and Washington, D.C., the hilly county is one of the most sparsely populated areas in the state. Bordered by West Virginia to the south and west and by Pennsylvania to the north, the bucolic region drew Mike Koch and his husband, Pablo Solanet, who both lived and worked in D.C. (as a financial services executive and a chef, respectively), to buy a 130-acre farm there in 1997.
They knew they wanted to start a business, and when deciding among beekeeping, growing greens and herbs, and cheesemaking, the couple chose cheese. "We'd been reading about Mary Keehn at Cypress Grove, Allison Hooper and Bob Reese at Vermont Creamery, [Judy Schad] at Capriole," Koch says. "We're three hours from 16 million mouths in the Mid-Atlantic foodshed. We thought there was a gap to be filled for goat cheese in the [region]."
Mike Koch and Pablo Solanet, the founders of FireFly Farms
Though the couple had no prior cheesemaking experience, they dove in. The men attended a cheese technology course at the University of Wisconsin at Madison, and between Solanet's culinary background and some chemistry courses Koch took in college, they found their way, discovering that "cheese is something you learn to make by doing it again and again and again," Koch says. They founded FireFly Farms in 2000, and their first wheels hit markets in 2002.
The pair planned to begin with fresh chèvre, a soft-ripened pyramid, and blue cheese. The proximity of the bloomy-rind pyramid to the blue wheels in the creamery, however, created something else altogether. "The brie got into the blue and it totally changed the cheese," Solanet says. "I thought I'd made a mistake, but [the cross-pollination] made it creamy with a really mild blue-cheese flavor."
Koch and Solanet ran with the unintended consequences. During the summer of 2002, the cheese (christened MountainTop Bleu, a name inspired by the nearby Allegheny Plateau) won a blue ribbon at the American Cheese Society Judging & Competition. Since then, the blue-gray pyramid has racked up 27 more awards—making it FireFly's most decorated cheese. It's little wonder: With an understated, earthy funk from the blue cultures and a gooey texture that develops as the cheese ripens from the outside in, MountainTop Bleu is a unique but approachable crowd-pleaser.
"The first time I tried it, I didn't realize [what it was]," says Alicia Clugh, founder of the Maryland Cheese Guild. "I always say to people, if you don't think you like blue cheese, try it— this is like a gateway drug."
FireFly Farms' retail shop in Accident, Md.
Today MountainTop Bleu is part of FireFly's growing line, which also includes the cooked-curd wheel Bella Vita and an aged washed rind named Cabra La Mancha, among others. In 2017 the farm will produce 200,000 pounds of cheese, according to director of operations Matt Cedro, who has been with the company since 2003 and now runs day-to-day production. The business includes a retail outlet and a 3,000-square-foot creamery built in 2011 (the original creamery was down the road in Bittinger, Md.), and employs 25 people, 15 of whom are full-time. The company sources milk from a network of seven goat dairies just over the border in Somerset County, Penn.
FireFly Farms is dedicated to creating opportunities in this rural region, says Koch, who served as Garrett County's director of economic development from 2012 to 2015. "It's remarkable to see what they've done—where they've done it," Clugh adds. In an area where farmers struggle to make a living, Koch and his team are devoted to their milk suppliers. They pay higher milk prices than the farmers would get in the commodity market and offer incentives for high quality.
"In 2016, 44 percent of the value of our cheese sales went into the pockets of our farmers," Koch says. "We care about that—if they succeed, we succeed."
In an economy driven heavily by tourism (nearby Deep Creek Lake draws visitors from across the region) and the seasonal, often part-time jobs that come with it, FireFly staffers enjoy health benefits, paid sick time and vacation time, and a retirement plan. Employee retention is high as a result, Cedro says. Some workers have stayed on board a decade or longer—including Cedro's wife, Andrea, who runs sales and marketing, and director of cheesemaking Dan Porter.
Cedro started at FireFly as an apprentice and now works with new hires. "First, they become sanitarians—sanitation is number one in cheesemaking," he says. "Slowly but surely we integrate them into the cheesemaking process."
Director of operations Mike Cedro (center) stands with members of the cheesemaking team
COMPLICATED CULTURES
Currently seven FireFly cheesemakers are trained to make MountainTop Bleu. After the goat's milk is pasteurized, cultured (with both P. candidum and P. roqueforti), and set with rennet, it rests 30 minutes before curds are cut into marble-size pieces and stirred. "The goal is to get the curd to the same consistency every time for when it goes into the molds," Cedro says.
A curious kid at one of the Pennsylvania farms where FireFly sources its milk
Reaching that goal takes skill, he says, because the stirring process changes depending on the fat and protein levels in the milk and the amount of moisture in the curds. The most experienced cheesemakers, then, get the task. "It's a 'feel' thing," Cedro says, "something you learn over time." When curds are ready, team members ladle them into pyramid molds. The cheeses drain a day before they're unmolded and soaked in brine a few hours before heading to the aging room.
During ripening, blue mold appears on the cheese's surface first. Staffers then have a two-day window before candidum growth emerges to pierce the pyramids, which encourages MountainTop's delicate veining to develop in the paste. Soon after, Cedro explains, white mold grows on the rind, covering the blue mold and suppressing its growth. As the cheese matures, "you get a balance of the mild blue flavor with that gooeyness [from the] soft-ripening process," induced by the candidum, he says.
After two weeks, the cheese is wrapped for sale and transferred to cold storage, where low temperatures curtail ripening. The team holds the cheese until it reaches just the right point—most retailers and distributors prefer to receive the cheese when it's about 30 days old, Cedro says, so they have time to sell it at varying levels of maturity. MountainTop Bleu "reaches its peak anywhere from 60 to 90 days from the beginning of production," he adds.
Once shipped, MountainTop Bleu makes its way to FireFly's retail and restaurant customers. The company will sell almost $2 million worth of cheese this year, helping to stimulate the economy further—fostering full-time, career-track jobs with benefits and offering fair prices for farmers, thereby allowing them to expand their herds—in this corner of the countryside.
"They have their act together," Clough says of FireFly Farms. With more than two decades of careful planning directed by Koch, Solanet, and team, this is clearly—wait for it—no accident.
Janssen's Market
Standard Market
1508 Aurora Ave.
333 E. Ogden Ave.
FireFly Farms Creamery & Market
Accident, MD
Gilbert's Provisions
25 Commerce St.
Tastings Gourmet Market
1410 Forest Dr.
Boston Cheese Cellar
18 Birch St.
Roslindale, MA
Shop-Rite
808 Rte. 46
Eastern District
1053 Manhattan Ave.
Cheesetique
2411 Mt. Vernon Ave.
The Organic Butcher of McLean
6712 Old Dominion Dr.
In addition to the shops above, FireFly Farms cheeses may be found throughout the Mid-Atlantic in grocery stores such as MOM's Organic Market, Whole Foods Market, and Wegmans.
ENJOYING MOUNTAINTOP BLEU
When MountainTop Bleu is young and still firm, the cheese holds its shape when cut and may be crumbled over spinach salads sweetened with berries or softened atop a burger. When the pyramid ages, spoon its gooey paste onto crackers or baguette slices and dollop with plum or fig jam—those lush, round fruit flavors complement the understated blue flavor and creamy texture of the cheese beautifully.
Leigh Belanger
Leigh Belanger is culture's former food editor. She's been a food writer, editor, and project manager for over a decade— serving as program director for Chefs Collaborative and contributing to local newspapers and magazines. Her first book, The Boston Homegrown Cookbook, was published in 2012. She lives and cooks in Boston with her family.
Photographer Callie Lindsey
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Everything You Need to Know About Pairing Rosé and Cheese


Pearson: "We were always chasing the game."
The Reds defender spoke to the press following the Aston Villa match.
Reds defender Matty Pearson faced up to the press yesterday following the 3-0 defeat against Aston Villa.
A recent run of good results came to an end at Oakwell yesterday evening as Barnsley were on the end of some ruthlessly efficient Aston Villa play, going down 3-0 on the day of the Club's 130th anniversary.
Whilst the man signed from Accrington Stanley this summer didn't feel the 3-0 scoreline reflected the game truthly, he admitted that the Reds were part of their own downfall after mistakes led to all three of the visitors goals.
"There wasn't much in it in the first half, apart from their two goals, which were really really soft. One's a mistake, the other's a penalty. And then we were always chasing the game. We'd a big mountain to climb then and gave ourselves too much to do.
"It's just a shame really, because I thought we were okay first half but those goals killed us. But it's all about scoring goals, and we didn't score.
"It was 3-0 today, but it wasn't from our point of view a 3-0 game. We just need the fans to stay with us. We can feel hard done by, or we can put it right. And we've next week now to put it right."
Paul Heckingbottom's Aston Villa Reaction.
The Reds Gaffer was reacting to the 3-1 defeat against high-flying Aston Villa in the Sky Bet Championship.
Thiam: "It was another important step."
Reds forward Mamadou Thiam reacted to Saturday's latest Sky Bet League one victory.


The Glass Girl is ready at last! On 8 September it was prematurely launched, but now it's truly available. Click on the image if you'd like a copy.
And here's a Spotify link to the soundtrack to How To Make Life Nice - or the imagined film, starring say Emma Thompson or Tamsin Greig.