bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparisons and Intercorrelations of Physical Performance Variables of Operational Preparedness in Special Operations Forces
Authors: Ross Jeremy A , Winters Joshua D , Royer Scott D , Hoch Matthew C , Bergin Reiley , Morelli Nathan , Conley Caitlin , Sheppard Ryan L , Heebner Nicholas R
Published: December 2021

Introduction

Marine Forces Special Operations Command (MARSOC) deploys teams of operators (OP) and enablers (EN) to accomplish special operations missions. OP and EN are required to train and deploy together to accomplish these missions; however, they have different training and selection pipelines. Advanced strength and conditioning training strategies are applied to both OP and EN to enhance physical preparedness; however, it is unclear how the selection pipeline of these two personnel types affects overall physical preparedness and the relationships between performance variables. The purpose of this study is to gain a greater understanding of the relationships of a wide array of physical preparedness variables in OP and EN in an effort to streamline testing and training strategies.

Materials and Methods

For this study, 155 male (82 OP, 73 EN) MARSOC personnel (age: 29.5 ± 4.9 years, mass: 87.9 ± 11.1 kg, height: 1.79 ± 0.07 m) completed a physical preparedness assessment that included a DEXA assessment of body composition (BF%), 27.4 m sprint (30 yd), countermovement jump (VJ), 5–10–5 pro-agility (Agility), medicine ball toss (UBP), isometric mid-thigh pull (IMTP), and a 30 second (AnC) and 5 minute (AC) non-motorized treadmill run. Independent samples t tests, Mann–Whitney U tests, and Spearman’s Rank correlations were used to compare variables between OP and EN.

Results

OP demonstrated greater VJ, UBP, IMTP, AnC, and AC (P < 0.05); and significantly lower BF% and agility time (P < 0.05). Measurements of mass, height, body mass index, and 30 yd were not significantly different (P > 0.05). Weak to moderate correlations were seen between anthropometric and performance variables. OP and EN demonstrated similar correlations for most performance and anthropometric variables.

Conclusions

These results suggest that MARSOC OP demonstrate better physical preparedness over EN, while similar trends are observed between performance variables. Tests with moderate to high correlations may be removed from the protocol to account for testing time constraints. Height, weight, and BF% variables are poorly correlated with performance, particularly in OP, questioning their value in physical performance assessments in this population.
Physical Exercise as Treatment for PTSD: A Systematic Review and Meta-Analysis
Authors: Björkman Frida , Ekblom Örjan
Published: December 2021

Introduction

Post-traumatic stress disorder (PTSD) is a cluster of physical and psychiatric symptoms following military or civilian trauma. The effect of exercise on PTSD symptoms has previously been investigated in several studies. However, it has not been fully determined what type of exercise most impacts PTSD symptoms. The aim of the present study was to systematically review the effects of different types of exercise on PTSD symptom severity and symptoms of coexisting conditions in adults.

Materials and Methods

Electronic searches were conducted in the databases PubMed, APA PsycInfo, and SportDiscus, from database inception up until February 1, 2021. Inclusion criteria were randomized controlled trials published in English, participants having a PTSD diagnosis or clinically relevant symptoms, and participants randomly allocated to either a non-exercising control group or an exercise group. Data concerning the number of participants, age, exercise type and duration, PTSD symptom severity (primary outcome), and symptoms of coexisting conditions (secondary outcomes) were extracted. The subgroup analysis included high or low training dose, military trauma versus non-military trauma, the type of intervention (yoga versus other exercise), active or passive control condition, group training versus individual exercise, and study quality. The study quality and risk of bias were assessed using grading of recommendation assessment, development and evaluation (GRADE) guidelines. A meta-analysis was performed with a mixed-effects model and restricted maximum likelihood as model estimator, and effect size was calculated as the standardized difference in mean and 95% CI.

Results

Eleven studies were included in the present review. Results showed a main random effect of exercise intervention (0.46; 95% CI: 0.18 to 0.74) and a borderline significant interaction between more voluminous (>20 hours in total) and less voluminous (≤20 hours in total) exercise interventions (P = .07). No significant findings from the subgroup analysis were reported. The secondary outcome analysis showed a small but significant effect of exercise on depressive symptoms (0.20, 95% CI: 0.01 to 0.38), and a larger effect on sleep (0.51, 95% CI: 0.29 to 0.73). For substance use (alcohol and drugs combined) and quality of life, we found significant effects of 0.52 (95% CI: 0.06 to 0.98) and 0.51 (95% CI: 0.34 to 0.69), respectively. No significant effect was found for anxiety (0.18, 95% CI: −0.15 to 0.51), and no sign of publication bias was found.

Conclusions

Exercise can be an effective addition to PTSD treatment, and greater amounts of exercise may provide more benefits. However, as there were no differences found between exercise type, possibly due to the inclusion of a low number of studies using different methodologies, further research should aim to investigate the optimal type, dose, and duration of activity that are most beneficial to persons with PTSD.
Bias in apparent dispersion measure due to de-magnification of plasma lensing on background radio sources
Authors: Er Xinzhong , Yu Jiangchuan , Rogers Adam , Liu Shihang , Mao Shude
Published: December 2021

The effect of ionized gas on the propagation of radio signals is known as plasma lensing. Unlike gravitational lensing, plasma lensing causes both magnification and strong de-magnification effects to background sources. We study the cross-section of plasma lensing for two density profiles, the Gaussian and power-law models. In general, the cross-section increases with the density gradient. Radio sources can be used to measure the free electron density along the line of sight. However, plasma lensing de-magnification causes an underestimate of the electron density. Such a bias increases with the electron density, and can be up to $\sim 15{{\ {\rm per \ cent}}}$ in the high density region. There is a large probability that high density clumps will be missed due to this bias. The magnification of plasma lensing can also change the luminosity function of the background sources. The number density of sources on both the high- and low-luminosity ends can be overestimated due to this biasing effect.
Orbit decay of 2–100 au planetary remnants around white dwarfs with no gravitational assistance from planets
Authors: Veras Dimitri , Birader Yusuf , Zaman Uwais
Published: December 2021

A widely held assumption is that each single white dwarf containing observable rocky debris requires the presence of at least one terrestrial or giant planet to have gravitationally perturbed the progenitor of the debris into the star. However, these planets could have been previously engulfed by the star or escaped the system, leaving behind asteroids, boulders, cobbles, pebbles, sand, and dust. These remaining small bodies could then persist throughout the host star’s evolution into a white dwarf at ≈2–100 au scales, and then be radiatively dragged into the white dwarf without the help of a planet. Here, we identify the parameter space and cooling ages for which this one metal-pollution mechanism is feasible by, for the first time, coupling Poynting–Robertson drag, the Yarkovsky effect, and the YORP effect solely from rapidly dimming white dwarf radiation. We find that this no-planet pollution scenario is efficient for remnant 10−5 to 10−4 m dust up to about 80 au, 10−4 to 10−3 m sand up to about 25 au, and 10−3 to 10−2 m small pebbles up to about 8 au, and perhaps 10−1 to 100 m small boulders up to tens of au. Further, young white dwarf radiation can spin-up large strengthless boulders with radii of 102–103 m to destruction, breaking them down into smaller fragments that then can be dragged towards the white dwarf. Our work hence introduces a planetless metal-pollution mechanism that may be active in some fraction of white dwarf planetary systems.
Tracking the orbit of unresolved subhaloes for semi-analytic models
Authors: Delfino Facundo M , Scóccola Claudia G , Cora Sofía A , Vega-Martínez Cristian A , Gargiulo Ignacio D
Published: December 2021

We present a model to track the orbital evolution of ‘unresolved subhaloes’ (USHs) in cosmological simulations. USHs are subhaloes that are no longer distinguished by halo finders as self-bound overdensities within their larger host system due to limited mass resolution. These subhaloes would host ‘orphan galaxies’ in semi-analytic models of galaxy formation and evolution (SAMs). Predicting the evolution of the phase-space components of USHs is crucial for the adequate modelling of environmental processes, interactions, and mergers implemented in SAMs that affect the baryonic properties of orphan satellites. Our model takes into account dynamical friction drag, mass-loss by tidal stripping and merger with the host halo, involving three free parameters. To calibrate this model, we consider two DM-only simulations of different mass resolution (MultiDark simulations). The simulation with higher mass resolution (smdpl; $m_{\rm DM} = 9.6 \times 10^7\, h^{-1}\, \mathrm{M_{\odot }}$) provides information about subhaloes that are not resolved in the lower mass resolution one (mdpl2; $m_{\rm DM} = 1.5 \times 10^9\, h^{-1}\, \mathrm{M_{\odot }}$); the orbit of those USHs is tracked by our model. We use as constraining functions the subhalo mass function (SHMF) and the two-point correlation function (2PCF) obtained from smdpl, being the latter a novel aspect of our approach. While the SHMF fails to put tight constraints on the efficiency of dynamical friction and the merger condition, the addition of clustering information helps us to specify the parameters of the model related to the spatial distribution of subhaloes. Our model allows to achieve good convergence between the results of simulations of different mass resolution, with a precision better than 10 per cent for both SHMF and 2PCF.
Observed structural parameters of EAGLE galaxies: reconciling the mass–size relation in simulations with local observations
Authors: de Graaff Anna , Trayford James , Franx Marijn , Schaller Matthieu , Schaye Joop , van der Wel Arjen
Published: December 2021

We use mock images of z = 0.1 galaxies in the 100 Mpc EAGLE simulation to establish the differences between the sizes and morphologies inferred from the stellar mass distributions and the optical light distributions. The optical, r-band images used were constructed with a radiative transfer method to account for the effects of dust, and we measure galaxy structural parameters by fitting Sérsic models to the images with galfit. We find that the derived half-light radii differ systematically from the stellar half-mass radii, as the r-band sizes are typically 0.1 dex larger, and can deviate by as much as ${\approx}0.5\,$ dex, depending on the dust attenuation and star formation activity, as well as the measurement method used. Consequently, we demonstrate that the r-band sizes significantly improve the agreement between the simulated and observed stellar mass–size relation: star-forming and quiescent galaxies in EAGLE are typically only slightly larger than observed (by 0.1 dex), and the slope and scatter of the local relation are reproduced well for both populations. Finally, we compare the obtained morphologies with measurements from the GAMA survey, finding that too few EAGLE galaxies have bulge-like light profiles (Sérsic indices of n ∼ 4). Despite the presence of a significant population of triaxial systems among the simulated galaxies, the surface brightness and stellar mass density profiles tend to be closer to exponential discs (n ∼ 1–2). Our results highlight the need to measure the sizes and morphologies of simulated galaxies using common observational methods in order to perform a meaningful comparison with observations.
Dwarf stellar haloes: a powerful probe of small-scale galaxy formation and the nature of dark matter
Authors: Deason Alis J , Bose Sownak , Fattahi Azadeh , Amorisco Nicola C , Hellwing Wojciech , Frenk Carlos S
Published: December 2021

We use N-body cosmological simulations and empirical galaxy models to study the merger history of dwarf-mass galaxies (with $M_{\rm halo}\sim 10^{10}\, \mathrm{M}_\odot$). Our input galaxy models describe the stellar mass–halo mass relation, and the galaxy occupation fraction. The number of major and minor mergers depends on the type of dark matter; in particular, minor mergers are greatly suppressed in warm dark matter models. In addition, the number of mergers that bring in stars is strongly dependent on the galaxy occupation model. For example, minor mergers are negligible for stellar halo growth in models with a high mass threshold for galaxy formation (i.e. $10^{9.3}\, \mathrm{M}_\odot$ at z = 0). Moreover, this threshold for galaxy formation can also determine the relative difference (if any) between the stellar haloes of satellite and field dwarfs. Using isolated simulations of dwarf–dwarf mergers, we show that the relative frequency of major and minor mergers predict very different stellar haloes: Typically, ‘intermediate’ dark matter merger ratios (∼1:5) maximize the growth of distant stellar haloes. We discuss the observability of dwarf stellar haloes and find that the surface brightness of these features are incredibly faint. However, when several dwarfs are stacked together, models that form particularly rich stellar haloes could be detectable. Finally, we show that stellar streams in the Galactic halo overlapping in phase space with known dwarf satellites are likely remnants of their stripped stellar haloes. The mere existence of dwarf stellar haloes can already put constraints on some small-scale models, and thus observational probes should be a high priority.
Physics of radio emission in the long-period pulsars
Authors: Jones P B
Published: December 2021

Recent multifrequency measurements of pulse widths W50 for the long-period pulsar J0250+5854 by Agar et al. provide a unique insight into the emission process owing to its small polar-cap radius. The frequency dependence of W50 can be simply understood as a consequence of the emitting plasma remaining under acceleration during the interval of radio emission. This is possible in a plasma of ions and protons but not in one of high-multiplicity electron–positron pairs. Extension of the model to the pulse profiles of the general pulsar population is considered briefly.
Landscape and Climatic Variations Shaped Secondary Contacts amid Barn Owls of the Western Palearctic
Authors: Cumer Tristan , Machado Ana Paula , Dumont Guillaume , Bontzorlos Vasileios , Ceccherelli Renato , Charter Motti , Dichmann Klaus , Kassinis Nicolaos , Lourenço Rui , Manzia Francesca , Martens Hans-Dieter , Prévost Laure , Rakovic Marko , Roque Inês , Siverio Felipe , Roulin Alexandre , Goudet Jérôme
Published: December 2021

The combined actions of climatic variations and landscape barriers shape the history of natural populations. When organisms follow their shifting niches, obstacles in the landscape can lead to the splitting of populations, on which evolution will then act independently. When two such populations are reunited, secondary contact occurs in a broad range of admixture patterns, from narrow hybrid zones to the complete dissolution of lineages. A previous study suggested that barn owls colonized the Western Palearctic after the last glaciation in a ring-like fashion around the Mediterranean Sea, and conjectured an admixture zone in the Balkans. Here, we take advantage of whole-genome sequences of 94 individuals across the Western Palearctic to reveal the complex history of the species in the region using observational and modeling approaches. Even though our results confirm that two distinct lineages colonized the region, one in Europe and one in the Levant, they suggest that it predates the last glaciation and identify a secondary contact zone between the two in Anatolia. We also show that barn owls recolonized Europe after the glaciation from two distinct glacial refugia: a previously identified western one in Iberia and a new eastern one in Italy. Both glacial lineages now communicate via eastern Europe, in a wide and permeable contact zone. This complex history of populations enlightens the taxonomy of Tyto alba in the region, highlights the key role played by mountain ranges and large water bodies as barriers and illustrates the power of population genomics in uncovering intricate demographic patterns.
Clinical features of Behçet’s disease patients with joint symptoms in Japan: A national multicenter study
Authors: Tono Toshihiro , Kikuchi Hirotoshi , Sawada Tetsuji , Takeno Mitsuhiro , Nagafuchi Hiroko , Kirino Yohei , Tanaka Yoshiya , Yamaoka Kunihiro , Hirohata Shunsei
Published: December 2021

Objectives

Approximately 30–60% of Behçet’s disease patients exhibit joint symptoms. The aim of this study was to determine the clinical characteristics of such patients in Japan.

Methods

This study retrospectively analyzed 151 Behçet’s disease patients with joint symptoms who had been treated at seven cooperative medical institutions from 2007 to 2017. We investigated their clinical characteristics and treatments.

Results

The most commonly affected joints were the knee, ankle, and proximal interphalangeal joints. Of the cases with pain and swelling, 18 of 293 joints (11 cases) displayed narrowing of the cleft or deformity by X-ray analysis. Improvement in their arthritis was observed in 80% of the patients who received steroids as initial treatment; however, the rate of improvement was lower in patients who had received prednisolone (PSL) at <10 mg/day. The recurrence of joint symptoms was significantly less common in the colchicine group than in the PSL group.

Conclusions

These results suggest that PSL is effective for remission induction for the treatment of joint symptoms of Behçet’s disease. Additionally, colchicine is effective in preventing the recurrence of joint symptoms in Behçet’s disease. Furthermore, joint damages like joint space narrowing or with any deformity can often be observed in Behçet’s disease.
Effect of gait protocols and postoperative shoes on off-loading of forefoot in preoperative patients for forefoot disorders
Authors: Kasai Taro , Tsuji Marina , Takeda Ryutaro , Chang Song Ho , Anzai Emi , Nakajima Kanako , Tanaka Sakae , Ohta Yuji , Matsumoto Takumi
Published: December 2021

Objectives

The purpose of this study was to clarify the effect of gait protocols and postoperative shoes on forefoot load in preoperative patients for forefoot disorders and compare footwear comfort between different types of postoperative shoes.

Methods

Fourteen subjects scheduled to undergo forefoot surgeries were recruited. The maximum force under the forefoot region was measured during 10 m straight walking in two gait patterns with six different shoe types. Visual analogue scale (VAS) scores for footwear comfort, subjective lower thigh pain, and electrical activities of lower thigh muscles were also evaluated.

Results

The body weight-normalized maximum force under the forefoot region significantly decreased in step-to gait compared to normal gait regardless of the shoe types used. Under the same gait condition, no significant difference was observed in the forefoot off-loading effect between the different shoe types used. Significantly worse VAS scores, significantly higher tibialis anterior muscle activities, and complaints of lower thigh pain were demonstrated in the gait with the reverse camber shoe.

Conclusions

Gait protocol of step-to gait had more forefoot off-loading effect than postoperative shoes. The forefoot off-loading effect did not differ among the postoperative shoes, suggesting that postoperative shoes can be selected with an emphasis on footwear comfort.
Challenges in diagnosing COVID-19 related disease in pediatric patients with rheumatic disease
Authors: Sener Seher , Basaran Ozge , Lacinel Gurlevik Sibel , Kaya Akca Ummusen , Atalay Erdal , Kasap Cuceoglu Muserref , Balik Zeynep , Batu Ezgi Deniz , Bilginer Yelda , Ozsurekci Yasemin , Ozen Seza
Published: December 2021

Objectives

Multisystem inflammatory syndrome in children (MIS-C) is a rare but severe condition associated with coronavirus disease 2019. Here we aimed to raise awareness for the symptoms of MIS-C in patients with rheumatic diseases, emphasizing the challenges of the differential features.

Methods

We retrospectively evaluated the demographic and clinical characteristics, laboratory and imaging findings, treatments, and outcomes of six MIS-C patients with previous rheumatic disease.

Results

Three of the patients had familial Mediterranean fever (FMF), one had juvenile dermatomyositis, one had systemic juvenile idiopathic arthritis (JIA), and another patient had oligoarticular JIA. All FMF patients presented with fever and abdominal pain, two also had chest pain. The patient with systemic JIA presented with fever, rash, and myalgia. All patients had elevated inflammatory markers and high d-dimer levels. Chest imaging of two FMF patients showed infiltrations compatible with pneumonia. One FMF patient had mildly decreased systolic functions with a shortening fraction of 48% in his echocardiography. Intravenous immunoglobulin and methylprednisolone were administered to all patients. Anakinra was given to four patients.

Conclusions

Clinical and laboratory signs of MIS-C may overlap with the findings of various rheumatic diseases, and this may cause a delay in diagnosis.
Have the radiographic characteristics of total knee arthroplasty recipients in rheumatoid arthritis changed after the induction of biologic disease modifying antirheumatic drugs?
Authors: Fujimura Kenjiro , Haraguchi Akihisa , Sakurai Ryuta , Kamura Satoshi , Sakuraba Koji , Miyahara Hisaaki , Fukushi Jun-ichi
Published: December 2021

Objectives

Whether the characteristics of patients with rheumatoid arthritis (RA) undergoing total knee arthroplasty (TKA) have changed in the era of biologic disease-modifying antirheumatic drugs (bDMARDs) is unclear. We compared the radiographic findings of the knees in TKA recipients with RA before and after the introduction of bDMARDs.

Methods

Consecutive patients who underwent primary TKA between 1999 and 2002 (115 knees; 79 patients, group A) and between 2013 and 2017 (117 knees; 95 patients, group B) were retrospectively evaluated. Clinical data, including disease duration, medication, C-reactive protein, erythrocyte sedimentation rate, and rheumatoid factor, were collected. The Larsen classification, joint space narrowing (JSN), bone erosion, and geode and osteophyte formation were evaluated on preoperative radiographs.

Results

Osteophyte formation was significantly increased, and bone erosion and geode formation were significantly decreased in group B. In addition, medial-dominant JSN was significantly increased, and bicompartmental JSN was significantly decreased in group B. Medial-dominant JSN was positively and bone erosion was negatively associated with osteophyte formation.

Conclusions

Following the introduction of bDMARDs, typical radiographic findings of rheumatoid knees have decreased, and secondary osteoarthritis-like changes, characterized by osteophyte formation and medial-dominant JSN, have increased in the knees of TKA recipients.
Efficient target cleavage by Type V Cas12a effectors programmed with split CRISPR RNA
Authors: Shebanova Regina , Nikitchina Natalia , Shebanov Nikita , Mekler Vladimir , Kuznedelov Konstantin , Ulashchik Egor , Vasilev Ruslan , Sharko Olga , Shmanai Vadim , Tarassov Ivan , Severinov Konstantin , Entelis Nina , Mazunin Ilya
Published: December 2021

CRISPR RNAs (crRNAs) that direct target DNA cleavage by Type V Cas12a nucleases consist of constant repeat-derived 5′-scaffold moiety and variable 3′-spacer moieties. Here, we demonstrate that removal of most of the 20-nucleotide scaffold has only a slight effect on in vitro target DNA cleavage by a Cas12a ortholog from Acidaminococcus sp. (AsCas12a). In fact, residual cleavage was observed even in the presence of a 20-nucleotide crRNA spacer moiety only. crRNAs split into separate scaffold and spacer RNAs catalyzed highly specific and efficient cleavage of target DNA by AsCas12a in vitro and in lysates of human cells. In addition to dsDNA target cleavage, AsCas12a programmed with split crRNAs also catalyzed specific ssDNA target cleavage and non-specific ssDNA degradation (collateral activity). V-A effector nucleases from Francisella novicida (FnCas12a) and Lachnospiraceae bacterium (LbCas12a) were also functional with split crRNAs. Thus, the ability of V-A effectors to use split crRNAs appears to be a general property. Though higher concentrations of split crRNA components are needed to achieve efficient target cleavage, split crRNAs open new lines of inquiry into the mechanisms of target recognition and cleavage and may stimulate further development of single-tube multiplex and/or parallel diagnostic tests based on Cas12a nucleases.
Multiplex PCR Pathogen Detection in Acute Gastroenteritis Among Hospitalized US Children Compared With Healthy Controls During 2011–2016 in the Post–Rotavirus Vaccine Era
Authors: Harrison Christopher J , Hassan Ferdaus , Lee Brian , Boom Julie , Sahni Leila C , Johnson Coreen , Dunn James , Payne Daniel C , Wikswo Mary E , Parashar Umesh , Selvarangan Rangaraj
Published: December 2021

Background

Despite vaccine-induced decreases in US rotavirus (RV) disease, acute gastroenteritis (AGE) remains relatively common. We evaluated AGE pathogen distribution in hospitalized US children in the post–RV vaccine era.

Methods

From December 2011 to June 2016, the New Vaccine Surveillance Network (NVSN) conducted prospective, active, population-based surveillance in hospitalized children with AGE. We tested stools from 2 NVSN sites (Kansas City, Houston) with Luminex x-TAG Gastrointestinal Pathogen Panels (Luminex GPP) and analyzed selected signs and symptoms.

Results

For 660 pediatric AGE inpatients and 624 age-matched healthy controls (HCs), overall organism detection was 51.2% and 20.6%, respectively (P < .001). Among AGE subjects, GPP polymerase chain reaction detected >1 virus in 39% and >1 bacterium in 14% of specimens. Detection frequencies for AGE subjects vs HCs were norovirus (NoV) 18.5% vs 6.6%, RV 16.1% vs 9.8%, adenovirus 7.7% vs 1.4%, Shigella 4.8% vs 1.0%, Salmonella 3.1% vs 0.1%, and Clostridioides difficile in ≥2-year-olds 4.4% vs 2.4%. More co-detections occurred among AGE patients (37/660, 5.6%) than HCs (14/624, 2.2%; P = .0024). Per logistic regression analysis, ill contacts increased risk for NoV, RV, and Shigella (P < .001). More vomiting episodes occurred with NoV and RV, and more diarrheal episodes with Shigella and Salmonella. Modified Vesikari scores were highest for Shigella and lowest for C. difficile.

Conclusions

NoV detection was most frequent; however, RV remained important in hospitalized AGE in the post–RV vaccine era. Continued active surveillance is important to document ongoing vaccine effects, pathogen emergence, and baseline disease burden for new vaccines.
A cook with ‘burning in the thigh’ and a ‘hotspot’ in the groin!
Authors: Moy Wai Lun
Published: December 2021

Meralgia paresthetica (MP) is a condition characterised by abnormal sensations on the anterolateral aspect of the thigh due to the dysfunction of the lateral femoral cutaneous nerve. Here, I present a case of a 64-year-old female cook who attended the General Medicine clinic with 2 months of persistent numbness and ‘burning’ sensation over the right anterolateral thigh. Subsequent physical examination revealed the diagnosis of meralgia paresthetica. The significance of good history taking and thorough physical examination in reaching the diagnosis of meralgia paresthetica cannot be overemphasized. In most typical presentations, advanced imaging and neurodiagnostic testing do not add value to confirm the diagnosis. If the clinical diagnosis is doubtful, nerve conduction study and magnetic resonance imaging may still be performed to exclude other mimicking pathologies. Increasing awareness of MP among doctors unfamiliar with this condition will prevent the ordering of excessive investigations.
Na+ Sensitivity of the KAT2-Like Channel Is a Common Feature of Cucurbits and Depends on the S5-P-S6 Segment
Authors: Wang Li-Min , Zhao Li-Na , Shah Iftikhar Hussain , Ramirez Dora Cano , Boeglin Martin , Véry Anne-Aliénor , Sentenac Hervé , Zhang Yi-Dong
Published: December 2021

Inhibition of Shaker K+ channel activity by external Na+ was previously reported in the melon (Cucumis melo L.) inwardly rectifying K+ channel MIRK and was hypothesized to contribute to salt tolerance. In this study, two inward Shaker K+ channels, CsKAT2 from cucumber (Cucumis sativus) and ClKAT2 from watermelon (Citrullus lanatus), were identified and characterized in Xenopus oocytes. Both channels were inwardly rectifying K+ channels with higher permeability to potassium than other monovalent cations and more active when external pH was acidic. Similarly to MIRK, their activity displayed an inhibition by external Na+, thus suggesting a common feature in Cucurbitaceae (Cucumis spp., Citrullus spp.). CsKAT2 and ClKAT2 are highly expressed in guard cells. After 24 h of plant treatment with 100 mM NaCl, the three KAT2-like genes were significantly downregulated in leaves and guard cells. Reciprocal chimeras were obtained between MIRK and Na+-insensitive AtKAT2 cDNAs. The chimera where the MIRK S5-P-S6 segment was replaced by that from AtKAT2 no longer showed Na+ sensitivity, while the inverse chimera gained Na+ sensitivity. These results provide evidence that the molecular basis of the channel blockage by Na+ is located in the S5-P-S6 region. Comparison of the electrostatic property in the S5-P-S6 region in AtKAT2 and MIRK revealed four key amino acid residues potentially governing Na+ sensitivity.
Nonhomologous end joining as key to CRISPR/Cas-mediated plant chromosome engineering
Authors: Gehrke Fabienne , Schindele Angelina , Puchta Holger
Published: December 2021

Although clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein (Cas)-mediated gene editing has revolutionized biology and plant breeding, large-scale, heritable restructuring of plant chromosomes is still in its infancy. Duplications and inversions within a chromosome, and also translocations between chromosomes, can now be achieved. Subsequently, genetic linkages can be broken or can be newly created. Also, the order of genes on a chromosome can be changed. While natural chromosomal recombination occurs by homologous recombination during meiosis, CRISPR/Cas-mediated chromosomal rearrangements can be obtained best by harnessing nonhomologous end joining (NHEJ) pathways in somatic cells. NHEJ can be subdivided into the classical (cNHEJ) and alternative NHEJ (aNHEJ) pathways, which partially operate antagonistically. The cNHEJ pathway not only protects broken DNA ends from degradation but also suppresses the joining of previously unlinked broken ends. Hence, in the absence of cNHEJ, more inversions or translocations can be obtained which can be ascribed to the unrestricted use of the aNHEJ pathway for double-strand break (DSB) repair. In contrast to inversions or translocations, short tandem duplications can be produced by paired single-strand breaks via a Cas9 nickase. Interestingly, the cNHEJ pathway is essential for these kinds of duplications, whereas aNHEJ is required for patch insertions that can also be formed during DSB repair. As chromosome engineering has not only been accomplished in the model plant Arabidopsis (Arabidopsis thaliana) but also in the crop maize (Zea mays), we expect that this technology will soon transform the breeding process.
Cancer prevention, risk reduction, and control: opportunities for the next decade of health care delivery research
Authors: O’Malley Denalee M , Alfano Catherine M , Doose Michelle , Kinney Anita Y , Lee Simon J Craddock , Nekhlyudov Larissa , Duberstein Paul , Hudson Shawna V
Published: December 2021

In this commentary, we discuss opportunities to optimize cancer care delivery in the next decade building from evidence and advancements in the conceptualization and implementation of multi-level translational behavioral interventions. We summarize critical issues and discoveries describing new directions for translational behavioral research in the coming decade based on the promise of the accelerated application of this evidence within learning health systems. To illustrate these advances, we discuss cancer prevention, risk reduction (particularly precision prevention and early detection), and cancer treatment and survivorship (particularly risk- and need-stratified comprehensive care) and propose opportunities to equitably improve outcomes while addressing clinician shortages and cross-system coordination. We also discuss the impacts of COVID-19 and potential advances of scientific knowledge in the context of existing evidence, the need for adaptation, and potential areas of innovation to meet the needs of converging crises (e.g., fragmented care, workforce shortages, ongoing pandemic) in cancer health care delivery. Finally, we discuss new areas for exploration by applying key lessons gleaned from implementation efforts guided by advances in behavioral health.
Is tenofovir disoproxil fumarate associated with weight loss?
Authors: Shah Shahini , Pilkington Victoria , Hill Andrew
Published: December 2021

Background:

Recent clinical trials have shown weight gain associated with newer antiretrovirals. It is unclear how the nucleoside reverse transcriptase inhibitor backbone affects weight. Recent evidence suggests greater weight gain with tenofovir alafenamide (TAF) compared with tenofovir disoproxil fumarate (TDF). However, it is not fully understood whether TDF contributes to weight suppression.

Methods:

A systematic search of PubMed, Embase and clinicaltrials.gov was conducted to identify all randomized control trials comparing TDF/FTC or TDF to control in HIV-negative individuals. The primary endpoint included the number of events of 5% weight loss. Mantel–Haenszel test with random-effects modelling was used to calculate the odds ratio (OR) and 95% confidence intervals (95% CI). Further analyses of gastrointestinal (GI) adverse events were also undertaken.

Results:

Seven PrEP trials: PARTNERS, VOICE, TDF-2, Bangkok PrEP, iPrEX, FEM-PrEP and HPTN 084 were included in the analysis of weight loss, with a total sample size of 19 359. One study (HPTN 084) compared TDF/FTC to cabotegravir (CAB). HIV-negative individuals taking TDF were more likely to experience weight loss compared with control [odds ratio (OR) 1.44; 95% CI 1.12–1.85; P = 0.005). Exposure to TDF was also linked to greater odds of vomiting (OR 1.81; 95% CI 1.20–2.73; P < 0.005). There were no increased odds of nausea, diarrhoea or loss of appetite.

Conclusion:

There is evidence in HIV-negative individuals that TDF may be associated with weight loss. Further research should be carried out in HIV-positive individuals, and clinical trials of TDF/FTC should publish weight data to widen the evidence base.
Felix Jiri Weinberg. 2 April 1928—5 December 2012
Authors: Dunn-Rankin D.
Published: December 2021

Felix Weinberg's teenage years coincided with World War II. He spent much of the war in Nazi concentration camps, starting with Terezin in December 1942, followed by Auschwitz in December 1943, and finally Buchenwald, from which he was liberated on 11 April 1945. He joined Imperial College, London as a research assistant in 1951 and completed his PhD by 1954. He was appointed to a personal chair as professor of combustion physics in 1967, and he stayed at Imperial for his entire career. Weinberg was distinguished for his optical and electrical studies of flames and his pioneering development of innovative combustion methods. He invented a family of powerful optical tools in combustion, using both broad spectrum and laser light sources. His work on electrical diagnostics led to applications of electric fields to control combustion and to improved understanding of ionization and soot formation. He developed novel combustion devices that incorporated distinctive heat exchangers, thereby permitting the ignition and burning of very low calorific fuel–air mixtures. All of these works had a propelling influence on the global evolution of environmentally benign combustion furnaces. His wide-ranging service to academia, industry and scientific societies included visiting scholar appointments at universities around the world, consultancies for petroleum, chemical, aerospace and defence organizations, and active membership on committees and boards of governance for many scientific and professional bodies. He was author, co-author or editor of four books and well over 200 papers in the scientific literature.
Transmembrane topology and oligomeric nature of an astrocytic membrane protein, MLC1
Authors: Hwang Junmo , Park Kunwoong , Lee Ga-Young , Yoon Bo Young , Kim Hyunmin , Roh Sung Hoon , Lee Byoung-Cheol , Kim Kipom , Lim Hyun-Ho
Published: December 2021

MLC1 is a membrane protein mainly expressed in astrocytes, and genetic mutations lead to the development of a leukodystrophy, megalencephalic leukoencephalopathy with subcortical cysts disease. Currently, the biochemical properties of the MLC1 protein are largely unknown. In this study, we aimed to characterize the transmembrane (TM) topology and oligomeric nature of the MLC1 protein. Systematic immunofluorescence staining data revealed that the MLC1 protein has eight TM domains and that both the N- and C-terminus face the cytoplasm. We found that MLC1 can be purified as an oligomer and could form a trimeric complex in both detergent micelles and reconstituted proteoliposomes. Additionally, a single-molecule photobleaching experiment showed that MLC1 protein complexes could consist of three MLC1 monomers in the reconstituted proteoliposomes. These results can provide a basis for both the high-resolution structural determination and functional characterization of the MLC1 protein.
A nonlinear multi-scale model for blood circulation in a realistic vascular system
Authors: Qohar Ulin Nuha A. , Zanna Munthe-Kaas Antonella , Nordbotten Jan Martin , Hanson Erik Andreas
Published: December 2021

In the last decade, numerical models have become an increasingly important tool in biological and medical science. Numerical simulations contribute to a deeper understanding of physiology and are a powerful tool for better diagnostics and treatment. In this paper, a nonlinear multi-scale model framework is developed for blood flow distribution in the full vascular system of an organ. We couple a quasi one-dimensional vascular graph model to represent blood flow in larger vessels and a porous media model to describe flow in smaller vessels and capillary bed. The vascular model is based on Poiseuille’s Law, with pressure correction by elasticity and pressure drop estimation at vessels' junctions. The porous capillary bed is modelled as a two-compartment domain (artery and venous) using Darcy’s Law. The fluid exchange between the artery and venous capillary bed compartments is defined as blood perfusion. The numerical experiments show that the proposed model for blood circulation: (i) is closely dependent on the structure and parameters of both the larger vessels and of the capillary bed, and (ii) provides a realistic blood circulation in the organ. The advantage of the proposed model is that it is complex enough to reliably capture the main underlying physiological function, yet highly flexible as it offers the possibility of incorporating various local effects. Furthermore, the numerical implementation of the model is straightforward and allows for simulations on a regular desktop computer.
Risso's dolphins perform spin dives to target deep-dwelling prey
Authors: Visser Fleur , Keller Onno A. , Oudejans Machiel G. , Nowacek Douglas P. , Kok Annebelle C. M. , Huisman Jef , Sterck Elisabeth H. M.
Published: December 2021

Foraging decisions of deep-diving cetaceans can provide fundamental insight into food web dynamics of the deep pelagic ocean. Cetacean optimal foraging entails a tight balance between oxygen-conserving dive strategies and access to deep-dwelling prey of sufficient energetic reward. Risso's dolphins (Grampus griseus) displayed a thus far unknown dive strategy, which we termed the spin dive. Dives started with intense stroking and right-sided lateral rotation. This remarkable behaviour resulted in a rapid descent. By tracking the fine-scale foraging behaviour of seven tagged individuals, matched with prey layer recordings, we tested the hypothesis that spin dives are foraging dives targeting deep-dwelling prey. Hunting depth traced the diel movement of the deep scattering layer, a dense aggregation of prey, that resides deep during the day and near-surface at night. Individuals shifted their foraging strategy from deep spin dives to shallow non-spin dives around dusk. Spin dives were significantly faster, steeper and deeper than non-spin dives, effectively minimizing transit time to bountiful mesopelagic prey, and were focused on periods when the migratory prey might be easier to catch. Hence, whereas Risso's dolphins were mostly shallow, nocturnal foragers, their spin dives enabled extended and rewarding diurnal foraging on deep-dwelling prey.
Parallel generation of extensive vascular networks with application to an archetypal human kidney model
Authors: Cury L. F. M. , Maso Talou G. D. , Younes-Ibrahim M. , Blanco P. J.
Published: December 2021

Given the relevance of the inextricable coupling between microcirculation and physiology, and the relation to organ function and disease progression, the construction of synthetic vascular networks for mathematical modelling and computer simulation is becoming an increasingly broad field of research. Building vascular networks that mimicin vivomorphometry is feasible through algorithms such as constrained constructive optimization (CCO) and variations. Nevertheless, these methods are limited by the maximum number of vessels to be generated due to the whole network update required at each vessel addition. In this work, we propose a CCO-based approach endowed with a domain decomposition strategy to concurrently create vascular networks. The performance of this approach is evaluated by analysing the agreement with the sequentially generated networks and studying the scalability when building vascular networks up to 200 000 vascular segments. Finally, we apply our method to vascularize a highly complex geometry corresponding to the cortex of a prototypical human kidney. The technique presented in this work enables the automatic generation of extensive vascular networks, removing the limitation from previous works. Thus, we can extend vascular networks (e.g. obtained from medical images) to pre-arteriolar level, yielding patient-specific whole-organ vascular models with an unprecedented level of detail.
Theoretical Analysis of Principal Components in an Umbrella Model of Intraspecific Evolution
Authors: Estavoyer Maxime , François Olivier
Published: December 2021

Principal component analysis (PCA) is one of the most frequently-used approach to describe population structure from multilocus genotype data. Regarding geographic range expansions of modern humans, interpretations of PCA have, however, been questioned, as there is uncertainty about the wave-like patterns that have been observed in principal components. It has indeed been argued that wave-like patterns are mathematical artifacts that arise generally when PCA is applied to data in which genetic differentiation increases with geographic distance. Here, we present an alternative theory for the observation of wave-like patterns in PCA. We study a coalescent model – the umbrella model – for the diffusion of genetic variants. The model is based on genetic drift without any particular geographical structure. In the umbrella model, splits from an ancestral population occur almost continuously in time, giving birth to small daughter populations at a regular pace. Our results provide detailed mathematical descriptions of eigenvalues and eigenvectors for the PCA of sampled genomic sequences under the model. Removing variants uniquely represented in the sample, the PCA eigenvectors are defined as cosine functions of increasing periodicity, reproducing wave-like patterns observed in equilibrium isolation-by-distance models. Including rare variants in the analysis, the eigenvectors corresponding to the largest eigenvalues exhibit complex wave shapes. The accuracy of our predictions is further investigated with coalescent simulations. Our analysis supports the hypothesis that highly structured wave-like patterns could arise from genetic drift only, and may not always be artificial outcomes of spatially structured data. Genomic data related to the peopling of the Americas are reanalyzed in the light of our new theory.
Rapid multilocus adaptation of clonal cabbage leaf curl virus populations toArabidopsis thaliana
Authors: Hoyer J. Steen , Wilkins Olivia W. , Munshi Aanandi , Wiese Emma , Dubey Divya , Renard Savannah , Mortensen Karoline Rosendal Hartø , Dye Anna E. , Carbone Ignazio , Duffy Siobain , Ascencio-Ibáñez José Trinidad
Published: December 2021

Cabbage leaf curl virus (CabLCV) has a bipartite single-stranded DNA genome and infects the model plantArabidopsis thaliana. CabLCV serves as a model for the genusBegomovirus, members of which cause tremendous crop losses worldwide. We have used CabLCV as a model for within-plant virus evolution by inoculating individual plants with infectious clones of either a wild-type or mutagenized version of the CabLCV genome. Consistent with previous reports, detrimental substitutions in the Replication-associated gene (Rep) were readily compensated for by direct reversion and/or alternative mutations. A surprising number of common mutations were detected elsewhere in both viral segments (DNA-A and DNA-B) indicating convergent evolution and suggesting that CabLCV may not be as well adapted toA. thalianaas commonly presumed. Consistent with this idea, a spontaneous coat protein variant consistently rose to high allele frequency in susceptible accession Col-0, at a higher rate than in hypersusceptible accession Sei-0. Numerous high-frequency mutations were also detected in a candidate Rep binding site in DNA-B. Our results reinforce the fact that spontaneous mutation of this type of virus occurs rapidly and can change the majority consensus sequence of a within-plant virus population in weeks.