bluuebunny/crossref_metadata_2025 huggingface dataset:
Enhancement of optical phonons limited electron mobility in an AlGaN step-shaped quantum well
Authors: Jia DongYi , Qu Yuan , Ban ShiLiang
Published: March 2022

Achieving high conductivity in n-type AlGaN of deep ultraviolet light-emitting diodes is still a challenge nowadays. In the Lei–Ting equilibrium equation method framework, a four-layer quantum well with n-Al0.7Ga0.3N barriers and an Al0.55Ga0.45N/AlxGa1−xN bi-component well could obtain a much higher electron mobility μT than that in a single-component quantum well over a relatively broad Al content range 0.56 < x < 0.68. While the built-in electric field induces strong confinement, pushing the electron to the interface, the optical phonon mode at this interface could be component-modulated to disappear due to the ternary mixed crystal effect. A significant enhancement of electron mobility can be achieved by avoiding the scattering from optical phonons at the interface where the electron gathers. The optical phonon limited μT could reach 7966 cm2/V s at x = 0.58, which is almost five times of 1518 cm2/V s in the case of x = 0.55 and ten times of 822 cm2/V s for x = 0.70. Such a step-shaped quantum well with high electron mobility could be an alternate or insert layer to the high Al content n-layer to alleviate the current crowding.
Alternative measures of cow–calf efficiency for Afrikaner, Bonsmara, Nguni, Angus and Simmental sired calves
Authors: Pyoos G. M. , Scholtz M. M. , MacNeil M. D. , Theunissen A. , Neser F. W. C.
Published: March 2022

Context It is desirable to identify cows that produce higher weaning weights while consuming less feed in order to increase biological efficiency; however, there is no universally accepted metric for cow–calf efficiency. Aim Due to the common usage of ratios to express biological cow efficiency, despite their theoretical defects, these measures and alternatives to them were examined to understand better some of the complexities in improving cow efficiency. Methods The analyses were carried out using SAS. In model 1, 205-day calf weight/cow weight was used to define cow–calf efficiency and in model 3, 205-day calf weight per Large Stock Unit (LSU), which is a standard unit of energy consumed, was used to quantify efficiency. In models 2 and 4, 205-day calf weight was analysed using cow weight and Large Stock Unit, respectively, as covariates. Key results The use of ratios was biased in favour of the smaller Nguni cows. The Bonsmara and Angus sired calves attained 53% of the weight of their Nguni dams, and their weaning weight per Large Stock Unit was 169 ± 9 kg. However, Angus sired calves from Bonsmara dams were most efficient when efficiency was determined by analysis of covariance when cow weight and Large Stock Unit were used as covariates (162 ± 17 kg and 133 ± 22 kg), respectively. Conclusions The results indicate the difficulty in determining differences in cow–calf efficiency in the absence of a standard definition. The difference between output and input can be maximised, when traits are reported in consistent units like joules, financial currency, or carbon footprint. Implications This inconsistent definition of cow–calf efficiency makes its improvement challenging.
The evidence for and against competition between the European honeybee and Australian native bees
Authors: Prendergast Kit S. , Dixon Kinglsey W. , Bateman Philip W.
Published: March 2022

In Australia, the European honeybee (Apis mellifera) is an exotic, abundant, super-generalist species. Introduced two centuries ago, it thrives in the absence of many diseases adversely impacting honeybees elsewhere. Australia’s native bees may be vulnerable to competition with honeybees, leading to reduced abundances, reproductive output or even loss of bee species. We review the literature concerning competition between honeybees and Australian native bees in order to: (1) identify the valuence and strength of honeybee associations with native bees, and how this varies according to the response variable measured; (2) assess potential research biases; (3) use ecological theory to explain variation in results; and (4) identify key knowledge gaps. We found honeybees typically comprised the majority of individuals in surveys of Australian bee communities. Data on whether honeybees outcompete native bees is equivocal: there were no associations with native bee abundance, species richness, or reproductive output in most cases. However, there were more negative than positive associations. Data indicate effects of honeybees are species-specific, and more detailed investigations regarding how different species and life-history traits affect interactions with honeybees is needed. We propose the following investigations to address deficiencies in the current literature: greater geographic and landscape representation; trait-based investigations; quantifying resource availability and overlap; disease and predator interactions; experimental feral colony removals; and studies spanning multiple seasons and years. Identifying conditions under which honeybees have negative, neutral or positive effects on native bees, and how the ecological traits of native bees are affected by honeybee competition can guide conservation and management.
Researchers discover that helium-8’s nucleus is shaped like a rugby ball
Authors: Jarman Sam
Published: March 2022

Work by an international team has revealed that helium-8’s shell of neutrons is shaped like a rugby ball.
Approval needed
Authors: Austin Jim
Published: March 2022

A response to Jorge E Hirsch’s letter “In moderation”, which argues that the preprint platform arXiv’s moderation processes disadvantage authors with controversial views.
A physicist’s experience of the mental-health system
Authors: Mendelsohn Alexander
Published: March 2022

Having suffered from depression and other mental-health problems for more than 10 years, Alexander Mendelsohn wonders why the mental-health system lacks the quantitative rigour that physics benefits from.
The transformative power of physics
Authors: O’Meara Joanne
Published: March 2022

Joanne O’Meara reviews Ten Days in Physics that Shook the World: How Physicists Transformed Everyday Life by Brian Clegg.
The dependence on parameters of the inverse functor to the 𝐾-finite functor
Authors: Wallach Nolan
Published: March 2022

An interpretation of the Casselman-Wallach Theorem is that the

K
K

-finite functor is an isomorphism of categories from the category of finitely generated, admissible smooth Fréchet modules of moderate growth to the category of Harish-Chandra modules for a real reductive group,

G
G

(here

K
K

is a maximal compact subgroup of

G
G

). In this paper we study the dependence of the inverse functor to the

K
K

-finite functor on parameters. Our main result implies that holomorphic dependence implies holomorphic dependence. The work uses results from the excellent thesis of van der Noort. Also a remarkable family of universal Harish-Chandra modules, developed in this paper, plays a key role.
Isospectral Hyperbolic Surfaces of Infinite Genus
Authors: Fanoni Federica
Published: March 2022

We show that any infinite-type surface without planar ends admits arbitrarily large families of length isospectral hyperbolic structures. If the surface has infinite genus and its space of ends is self-similar, we construct an uncountable family of isospectral and quasiconformally distinct hyperbolic structures.
A Two-Year Evaluation of Flualprazolam Concentrations in Orange County Drivers: Effects on Driving and Field Sobriety Test Performance
Authors: Manaloto Fernando R , Meneses Vanessa M , Mata Dani C
Published: March 2022

Starting in early 2017, flualprazolam was detected in toxicology and seized drug cases across the USA. Due to the addition of fluorine to alprazolam, flualprazolam’s chemistry was enough to bypass targeted toxicology confirmations, and it has become increasingly available for purchase both on the dark web and in counterfeit pills. Flualprazolam was added to the exact mass screening regiment of the Orange County forensic laboratory in December 2018. Through data mining of previously analyzed cases, data were evaluated beginning from August 2018. Flualprazolam was subsequently added to the laboratory’s validated quantitative liquid chromatography dual mass spectrometry method in the summer of 2020, and all driving cases from August 2018 to June 2020 were re-analyzed to obtain concentrations. The police and drug recognition evaluation (if available) reports were collected and reviewed for all cases where flualprazolam was detected. Of the 203 cases containing quantifiable drug, the average flualprazolam concentration (median, range) was 22.8 ng/mL (15.4 ng/mL, 4.0–133.3 ng/mL). Only two cases had flualprazolam detected with no other drugs. The other most common drugs detected were cannabinoids (62%), ethanol (20%) and cocaine and/or methamphetamine (32%). The most common reason for the police investigation was an accident/collision (50%), and the most common time of officer contact was evening (18:00 to 23:59). The field sobriety test (FST) results were evaluated and showed a higher frequency of impaired performance in cases of flualprazolam in combination with other drugs. No conclusion could be made regarding the effect of flualprazolam alone on FST performance.
Inhibitory effect of ascorbate on tryptophan 2,3-dioxygenase
Authors: Yuasa Hajime Julie
Published: March 2022

Tryptophan 2,3-dioxygenase (TDO) and indoleamine 2,3-dioxygenase (IDO) catalyse the same reaction, oxidative cleavage of L-tryptophan (L-Trp) to N-formyl-kynurenine. In both enzymes, the ferric form is inactive and ascorbate (Asc) is frequently used as a reductant in in vitro assays to activate the enzymes by reducing the heme iron. Recently, it has been reported that Asc activates IDO2 by acting as a reductant; however, it is also a competitive inhibitor of the enzyme. Here, the effect of Asc on human TDO (hTDO) is investigated. Similar to its interaction with IDO2, Asc acts as both a reductant and a competitive inhibitor of hTDO in the absence of catalase, and its inhibitory effect was enhanced by the addition of H2O2. Interestingly, however, no inhibitory effect of Asc was observed in the presence of catalase. TDO is known to be activated by H2O2 and a ferryl-oxo (FeIV=O) intermediate (Compound II) is generated during the activation process. The observation that Asc acts as a competitive inhibitor of hTDO only in the absence of catalase can be explained by assuming that the target of Asc is Compound II. Asc seems to compete with L-Trp in an unusual manner.
‘It could never be just about beer’: race, gender, and marked professional identity in the US craft beer industry
Authors: Wilson Eli R
Published: March 2022

To critical observers, the growth and professionalization of the US craft beer industry over the last few decades has meant the expansion of yet another kind of workplace replete with standards of whiteness and masculinity. Yet the first-hand experiences of workers in this setting—one that values authenticity and features growing support for social inclusivity—remain understudied. This study asks how do women and people of color negotiate work identities in craft beer? Based on 56 in-depth interviews as well as ethnographic field research in US craft breweries, this study demonstrates how minoritized workers enact their work identities in ways that are both enabled and constrained by their workplace contexts. I find that women and people of color attempt to construct marked professional identities that adhere to existing standards of industry professionalism while selectively engaging their race and gender identities when it is advantageous to do so. I elaborate on how marked professional identities may especially resonate in organizational settings that prioritize authenticity and feature less entrenched organizational norms.
Characteristics and Risk Factors for Mortality by Coronavirus Disease 2019 Pandemic Waves in Fulton County, Georgia: A Cohort Study March 2020–February 2021
Authors: Chishinga Nathaniel , Smith Sasha , Gandhi Neel R , Onwubiko Udodirim N , Telford Carson , Prieto Juliana , Chamberlain Allison T , Khan Shamimul , Williams Steve , Khan Fazle , Sarita Shah N
Published: March 2022

Background

We examined differences in mortality among coronavirus disease 2019 (COVID-19) cases in the first, second, and third waves of the COVID-19 pandemic.

Methods

A retrospective cohort study of COVID-19 cases in Fulton County, Georgia, USA, reported to a public health surveillance from March 2020 through February 2021. We estimated case-fatality rates (CFR) by wave and used Cox proportional hazards random-effects models in each wave, with random effects at individual and long-term-care-facility level, to determine risk factors associated with rates of mortality.

Results

Of 75 289 confirmed cases, 4490 (6%) were diagnosed in wave 1 (CFR 31 deaths/100 000 person days [pd]), 24 293 (32%) in wave 2 (CFR 7 deaths/100 000 pd), and 46 506 (62%) in wave 3 (CFR 9 deaths/100 000 pd). Compared with females, males were more likely to die in each wave: wave 1 (adjusted hazard ratio [aHR], 1.5; 95% confidence interval [CI], 1.2–1.8), wave 2 (aHR 1.5, 95% CI, 1.2–1.8), and wave 3 (aHR 1.7, 95% CI, 1.5–2.0). Compared with non-Hispanic whites, non-Hispanic blacks were more likely to die in each wave: wave 1 (aHR, 1.4; 95% CI, 1.1–1.8), wave 2 (aHR, 1.5; 95% CI, 1.2–1.9), and wave 3 (aHR, 1.7; 95% CI, 1.4–2.0). Cases with any disability, chronic renal disease, and cardiovascular disease were more likely to die in each wave compared with those without these comorbidities.

Conclusions

Our study found gender and racial/ethnic disparities in COVID-19 mortality and certain comorbidities associated with COVID-19 mortality. These factors have persisted throughout the COVID-19 pandemic waves, despite improvements in diagnosis and treatment.
Endothelial Progenitor Cells in Coronary Artery Disease: From Bench to Bedside
Authors: Pelliccia Francesco , Zimarino Marco , De Luca Giuseppe , Viceconte Nicola , Tanzilli Gaetano , De Caterina Raffaele
Published: March 2022

Endothelial progenitor cells (EPCs) are a heterogeneous group of cells present in peripheral blood at various stages of endothelial differentiation. EPCs have been extensively investigated in patients with coronary artery disease (CAD), with controversial findings both on their role in atherosclerosis progression and in the process of neointimal growth after a percutaneous coronary intervention (PCI). Despite nearly 2 decades of experimental and clinical investigations, however, the significance of EPCs in clinical practice remains unclear and poorly understood. This review provides an update on the role of EPCs in the most common clinical scenarios that are experienced by cardiologists managing patients with CAD. We here summarize the main findings on the association of EPCs with cardiovascular risk factors, coronary atherosclerosis, and myocardial ischemia. We then discuss the potential effects of EPCs in post-PCI in-stent restenosis, as well as most recent findings with EPC-coated stents. Based on the mounting evidence of the relationship between levels of EPCs and several different adverse cardiovascular events, EPCs are emerging as novel predictive biomarkers of long-term outcomes in patients with CAD.
The common bottlenose dolphin (Tursiops truncatus) ecotypes of the western North Atlantic revisited: an integrative taxonomic investigation supports the presence of distinct species
Authors: Costa Ana P B , Mcfee Wayne , Wilcox Lynsey A , Archer Frederick I , Rosel Patricia E
Published: March 2022

Integrative taxonomy can help us to gain a better understanding of the degree of evolutionary divergence between taxa. In the western North Atlantic (wNA), two ecotypes (coastal and offshore) of common bottlenose dolphin, Tursiops truncatus, exhibit some external morphological differences, and previous genetic findings suggested that they could be different species. However, their taxonomy remains unsettled. Using an integrative approach comparing traditional and geometric morphometrics, mitochondrial and nuclear DNA, we evaluated evolutionary relationships between these ecotypes. We observed congruence among these lines of evidence, strongly indicating that the wNA ecotypes are following distinct evolutionary trajectories. Based on mitochondrial DNA analyses, we detected significant divergence (Nei’s dA = 0.027), unshared haplotypes and one fixed difference leading to complete diagnosability (percentage diagnosable = 100%) of the wNA coastal ecotype. We found morphological diagnosability and negligible nuclear gene flow between the wNA ecotypes. Integration of these multiple lines of evidence revealed that the wNA coastal ecotype is an independent evolutionary unit, appearing to be more closely related to coastal dolphins in the Gulf of Mexico and Caribbean Sea than to their parapatric offshore neighbours, while the offshore dolphins form a relatively cohesive worldwide unit, T. truncatus. We propose that this coastal ecotype is recognized as a distinct species, resurrecting the name Tursiops erebennus.
Characterizing Electrophysiological Response Properties of the Peripheral Auditory System Evoked by Phonemes in Normal and Hearing Impaired Ears
Authors: Riggs William J. , Hiss Meghan M. , Adunka Oliver F.
Published: March 2022

Objective:

This study aimed to characterize time and spectral domain characteristics of the phoneme-evoked electrocochleography (ECochG) response and explore potential associations between the ECochG spectral content, word recognition scores (WRSs), residual hearing, and aging in normal and hearing-impaired listeners.

Design:

This was a prospective study with 25 adult participants. All participants underwent intraoperative ECochG testing and responses were recorded from the round window niche. Participants were divided into two groups based on their preoperative pure tone average: normal/mild sensorineural hearing loss and moderate/moderately-severe sensorineural hearing loss. Target stimuli were a 40 ms /da/ and an 80 ms /ba/ presented in alternating polarity (rarefaction/condensation). Waveform response patterns were analyzed including amplitude, latency, and spectra. Structural similarity index measure (SSIM) was used to determine similarity between the stimulus spectrum and that of the ECochG differential waveform. Correlation analyses were carried out among pure tone average, SSIM, age, and WRS.

Results:

ECochG alternating waveform morphology evoked by the /da/ stimulus consisted of five prominent peaks labeled N1-N5. Its spectrum was dominated by the fundamental (F0) frequency. The ECochG alternating response evoked by /ba/ consisted of nine prominent peaks labeled N1-N9 and was also dominated by F0. Amplitudes and latencies were not statistically different between groups for both stimuli. Significant positive correlations were found between SSIM and WRS for responses evoked by /da/ (r = 0.56) and responses evoked by /ba/ (r = 0.67). High frequency pure tone average and the /ba/ SSIM were found to have a significant negative correlation (r = −0.58).

Conclusions:

Speech-like stimuli have become increasingly utilized in the assessment of auditory function. Here, we provided the groundwork for understanding how commonly employed syllable stimuli are encoded by the peripheral auditory system in regard to temporal and spectral characteristics. Expanding this work to include measurements of central auditory processing in conjunction with cochlear physiology is warranted to further understand the relationship between peripheral and central encoding of speech-like stimuli.
Continuous Determination of the Optimal Bispectral Index Value Based on Cerebrovascular Reactivity in Moderate/Severe Traumatic Brain Injury: A Retrospective Observational Cohort Study of a Novel Individualized Sedation Target
Authors: Froese Logan , Gomez Alwyn , Sainbhi Amanjyot Singh , Batson Carleen , Stein Kevin , Alizadeh Arsalan , Mendelson Asher A. , Zeiler Frederick A.
Published: March 2022

BACKGROUND:

We have sought to develop methodology for deriving optimal bispectral index (BIS) values (BISopt) for patients with moderate/severe traumatic brain injury, using continuous monitoring of cerebrovascular reactivity and bispectral electroencephalography.

METHODS:

Arterial blood pressure, intracranial pressure, and BIS (a bilateral measure that is associated with sedation state) were continuously recorded. The pressure reactivity index, optimal cerebral perfusion pressure (CPPopt), and BISopt were calculated. Using BIS values and the pressure reactivity index, a curve fitting method was applied to determine the minimum value for the pressure reactivity index thus giving the BISopt.

RESULTS AND CONCLUSIONS:

Identification of BISopt was possible in all of the patients, with both visual inspection of data and using our method of BISopt determination, demonstrating a similarity of median values of 44.62 (35.03–59.98) versus 48 (39.75–57.50) (p = 0.1949). Furthermore, our method outperformed common CPPopt curve fitting methods applied to BISopt with improved percent (%) yields on both the left side 52.1% (36.3–72.4%) versus 31.2% (23.0–48.9%) (p < 0.0001) and the right side 54.1% (35.95–75.9%) versus 33.5% (12.5–47.9%) (p < 0.0001). The BIS values and BISopt were compared with cerebral perfusion pressure, mean arterial pressure, and CPPopt. The results indicated that BISopt’s impact on pressure reactivity was distinct from CPPopt, cerebral perfusion pressure, or mean arterial pressure. Real-time BISopt can be derived from continuous physiologic monitoring of patients with moderate/severe traumatic brain injury. This BISopt value appears to be unassociated with arterial blood pressure or CPPopt, supporting its role as a novel physiologic metric for evaluating cerebral autoregulation. BISopt management to optimize cerebrovascular pressure reactivity should be the subject of future studies in moderate/severe traumatic brain injury.
Low molecular weight heparin reduces arterial blood lactic acid content and increases estimated glomerular filtration rate in patients with moderate Covid-19 pneumonia
Authors: Ma Li , Zeng Yigang , Zhao Bing , Xu Lili , Li Jian , Zhu Tongyu , Mao Enqiang
Published: March 2022

Background:

Coronavirus disease 2019 (Covid-19) remains a serious health threat worldwide. We aimed to investigate whether low molecular weight heparin (LMWH) can promote organ function recovery in moderate Covid-19 pneumonia patients.

Methods:

We initiated an LMWH protocol in Covid-19 patients with increased D-dimer, body mass index >30 kg/m2 or a history of diabetes from January 18, 2020 at Shanghai Public Health Clinical Center. In this retrospective study, we assigned moderate Covid-19 pneumonia patients admitted between January 18th and April 18, 2020 receiving the LMWH protocol to the LMWH group. Moderate patients who met the inclusion criteria but did not receive LMWH protocol were included in the control group by 1:2 propensity score matching. General clinical information, indicators for renal function, arterial blood gas analyses, arterial blood lactic acid content (mmol/L), and coagulation indexes at 0 day, 3 days, 7 days, and 11 days after admission were recorded and compared between the two groups.

Results:

There were 41 patients in the LMWH group and 82 patients in the control group. General information in both groups were similar. Compared to the control group, the arterial blood lactic acid content (mmol/L) at day 11 (1.3 [1.1, 1.7] vs. 1.2 [0.9, 1.3], P = 0.016) was reduced in the LMWH group. The estimated glomerular filtration rate (eGFR) in the LMWH group was higher than that in the control group at day 7 (108.54 [89.11, 128.17] vs. 116.85 [103.39, 133.47], P = 0.039) and day 11 (113.74 [94.49, 126.34] vs. 128.31 [112.75, 144.12], P 
= 0.003). The serum creatinine levels (Scr) in the LMWH group were lower than that in the control group at day 7 (62.13 [51.47, 77.64] vs. 55.49 [49.50, 65.75], P = 0.038) and day 11 (63.35 [50.17, 75.73] vs. 51.62 [44.62, 61.24], P = 0.005).

Conclusions:

LMWH treatment can reduce arterial blood lactic acid levels and improve eGFR in moderate Covid-19 pneumonia patients. Randomized controlled trials are warranted to further investigate this issue.

Trial registration:

ChiCTR.org.cn, ChiCTR2000034796.
Driving role of macrophages in transition from acute kidney injury to chronic kidney disease
Authors: Meng Xiaoming , Jin Juan , Lan Hui Yao
Published: March 2022

Acute kidney injury (AKI), characterized by acute renal dysfunction, is an increasingly common clinical problem and an important risk factor in the subsequent development of chronic kidney disease (CKD). Regardless of the initial insults, the progression of CKD after AKI involves multiple types of cells, including renal resident cells and immune cells such as macrophages. Recently, the involvements of macrophages in AKI-to-CKD transition have garnered significant attention. Furthermore, substantial progress has also been made in elucidating the pathophysiological functions of macrophages from the acute kidney to repair or fibrosis. In this review, we highlight current knowledge regarding the roles and mechanisms of macrophage activation and phenotypic polarization, and transdifferentiation in the development of AKI-to-CKD transition. In addition, the potential of macrophage-based therapy for preventing AKI-to-CKD transition is also discussed.
Lack of consensus in atypical congenital obstructive urethral lesions in children: Snapshot of the web-based ObsCUre (obstruction to the child urethra) study
Authors: Ng Rachel , Adam Ahmed , Poppleton Nathan , Oldmeadow Christopher , Deshpande Aniruddh V.
Published: March 2022

Background

Atypical Congenital Obstructive Urethral Lesions (ACOUL) are uncommon causes of urethral obstruction in children. They include Cobb’s collar or Moorman’s ring, Type III posterior urethral valve (PUV), congenital urethral narrowing and anterior urethral valves. This study is aimed to evaluate the knowledge and current practice amongst clinicians attending to ACOUL. An international online case based questionnaire was performed.

Materials and methods

A survey was administered to members of international urological societies. It included 22 clinical questions on cases with ACOUL (14 questions suitable for statistical analysis) using cases of Type I PUV as controls. Two sets of paired questions evaluated change in opinion(s) after additional information was provided.

Results

One hundred twenty-one participants responded with 71% reporting exposure of less than 5 cases per annum. In questions regarding diagnosis between 11.6% (14/121) and 21.5% (26/121) of participants identified the ACOUL as PUV. Among them, 66% of respondents agreed on ACOUL’s causative role in urethral obstruction. Gini coefficient was consistently lower for ACOUL compared to PUV: diagnosis (mean 0.33 vs. 0.44) and prognosis (0.23 vs. 0.43). High intra-rater concordance (kappa 0.420.57) was observed for paired questions–a mean of 5.79% (7.44% and 4.13% for questions 10 and 12, 16 and 17, respectively) of participants changed their answers from an alternate diagnosis to the correct diagnosis of ACOUL after viewing endoscopic images. High variation in management of ACOUL was noted (Gini 0.51).

Conclusions

This global snapshot survey identified substantial inconsistency among clinicians dealing with ACOUL. Although rarely encountered in clinical practice, better overall education of ACOUL is warranted.
Dose-Tracking Software: A Retrospective Analysis of Dosimetric Data in CT Procedures
Authors: Buono Mauro , Capussela Tiziana , Loffredo Filomena , Di Pasquale Maria Antonella , Serra Marcello , Quarto Maria
Published: March 2022

The increasing use of ionizing radiation in healthcare is causing growing alarm about radiation protection of patients and the doses they receive during procedures. Radiation dose assessment for patients in radiodiagnostic procedures is the subject of interest in view of the recent Italian D.Lgs 31 July 2020, n. 101 (Decreto Legislativo 31 luglio 2020, n. 101) and one of its most important focuses is the prescription to provide patient exposure information as an integral part of the examination report. Dose monitoring systems are therefore essential for the collection of the dosimetric data. In order to analyse potential and critical issues of these software, different systems, adopted at the Antonio Cardarelli Hospital in Naples, were employed. Data extracted from the DoseWatch software (GE Healthcare) and Gray Detector (EL.CO. S.r.l. Healthcare Solutions, Italy) and relating to several protocols adopted for computed tomography (CT), were retrospectively analysed for the purpose of identifying critical issues in the data acquisition and recording phase, comparing with Italian nationwide diagnostic reference levels (DRLs), as provided for in regulatory provisions for radiation safety. Multiphase examinations were also included in this study. Once the distributions of volumetric CT Dose Index (CTDIvol) and dose-length product (DLP) were determined for each acquisition phase and total DLP (DLPtot) for each examination, the 25th, 50th and 75th percentiles were calculated for each distribution and then compared with the relevant Italian nationwide DRLs. In addition, to improve protocol optimization and dose reduction the magnitude of the CT acquisition settings chosen in each procedure was evaluated. In conclusion, these systems allow accurate analysis of radiation dose according to equipment and protocol over time. For the application of optimization measures, a constant use of the dose tracking software is required, which can be translated into actions on scan parameters and prospective data analysis.
ASSOCIATION OF CHOROIDAL THICKNESS WITH RHEGMATOGENOUS RETINAL DETACHMENT REPAIR
Authors: Trivizki Omer , Eremenko Ron , Au Adrian , Rabinovitch David , Abumanhal Muhamad , Schwartz Shulamit , Segal Ori , Rabina Gilad
Published: March 2022

Purpose:

To compare the choroidal thickness before and after pars plana vitrectomy for rhegmatogenous retinal detachment repair.

Methods:

A retrospective case series of rhegmatogenous retinal detachment patients presenting between January 2015 and September 2020. Subfoveal choroidal thickness (SFCT) and anatomical success were measured in operated eyes and fellow eyes at presentation, as well as 3 months and 6 months after pars plana vitrectomy for rhegmatogenous retinal detachment repair.

Results:

A total of 93 patients (males 59%) with a mean age of 61.8 ± 15.2 years were included. Eighty-one patients were anatomically successful (Group 1) and 12 redetached (Group 2). The mean SFCT of the operated eye at presentation was 258.3 ± 82.0 µm in comparison with 257.5 ± 83.7 µm in the fellow eye (P = 0.96). Group 2 presented with thicker SFCT than Group 1 at baseline (309.2 ± 56.2 vs. 250.7 ± 82.8 µm; P = 0.01). Both groups demonstrated thinning trend throughout follow-up. At 6-month follow-up, the mean SFCT was 225.6 ± 75.5 µm (P = 0.05). Fellow-eye SFCT was stable throughout follow-up (257 ± 83.7 at baseline vs. 255 ± 80.2 µm at 6 months).

Conclusion:

Eyes with rhegmatogenous retinal detachment demonstrated thinning in the SFCT after vitrectomy surgery. Eyes with recurrent retinal detachment presented with a thicker choroid at baseline. Thicker SFCT at presentation may play a role in retinal redetachment.
Rethinking Ankle-Foot Orthosis Design: Feasibility Study of a Flexible AFO
Authors: Parrott Cathy Bieber , Giuffre Suzanne M. , Whiteside Joseph , Tully Emily G.
Published: March 2022

Introduction

Ankle-foot orthoses (AFOs) are devices used to control the position and motion of the ankle and foot, so a safe and more efficient gait pattern results for people with lower-limb dysfunction. To provide the ankle and foot control, an AFO is typically made of hard plastic material. Research has shown that discomfort, difficulty using the device, or perceived lack of walking improvement results in low adherence to AFO use. The purpose of this study was to investigate an AFO made of a more flexible material to see if these drawbacks are improved.

Methods

Participants with a wide range of neurologic and musculoskeletal pathologies were issued a flexible AFO (FAFO). Performance and satisfaction data were collected at baseline, 2-week, and 3-month time points. Data collection included measures of balance (Berg Balance Scale) and temporal and spatial gait parameters (collected via the GAITRite Walkway System). Walking endurance was measured with the 6-minute walk test. Patient satisfaction was investigated using the Orthotic and Prosthetic User Satisfaction Survey (OPUS). Wearing adherence was measured as a percentage of the number of hours of wearing the FAFO per day.

Results

Statistical analysis using a paired t-test showed improvement was found from baseline to 2 weeks for balance and gait parameters of normalized velocity, double-limb support, and the Functional Ambulation Profile. These improvements were maintained at the 3-month follow-up. No improvement was found in patient satisfaction or walking endurance. Wearing adherence (number of hours per day) was found to be at the highest level of traditional AFO adherence-reported prior research.

Conclusions

This study found sufficient evidence to indicate the FAFO may be a feasible alternative to traditional hard material AFOs. Experimental trials comparing the FAFO to known gait improvements of currently accepted/traditional AFOs are needed.

Clinical Relevance

The FAFO investigated in this study provides beginning support for the feasibility of using ethylene-vinyl acetate thermoplastic as the sole material (coupled with the FAFO strapping system) for manufacturing an AFO. If further investigation confirms our findings, the FAFO can provide patients and orthotists another option to materials currently used in the manufacturing of an AFO.
Efficacy and Safety of Electroconvulsive Therapy in Patients With Deep Brain Stimulation
Authors: Bukowski Nicolas , Laurin Andrew , Laforgue Edouard-Jules , Preterre Cécile , Rouaud Tiphaine , Damier Philippe , Raoul Sylvie , Dumont Romain , Loutrel Olivier , Guitteny Marie , Derkinderen Pascal , Bulteau Samuel , Sauvaget Anne
Published: March 2022

Aim

Deep brain stimulation (DBS) has proven to be an effective therapy of some treatment-resistant psychiatric disorders and movement disorders. Comorbid depressive symptoms are common and difficult to manage. Treatment with electroconvulsive therapy (ECT) may be required. There are few published cases describing the safety and efficacy of ECT for patients with DBS implants, and there are no available guidelines for administration of ECT in patients with DBS and mood disorders. The current study had 3 aims: (i) to conduct a systematic review of case reports on patients with DBS implants who received ECT; (ii) to report the case of a 69-year-old man with a DBS implant for essential tremor, who required ECT; and (iii) to provide practical recommendations for ECT in patients with DBS implants.

Methods

We conducted a systematic review, in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, of existing case reports on patients with DBS implants administered ECT for psychiatric disorders.

Results

Our search yielded 25 cases of ECT in patients implanted with DBS systems. In addition, we here describe successful ECT management of major depressive disorder in a patient treated by DBS. We also set forth ECT management guidelines based on points of consensus. The 2 most important practical recommendations are to make sure the DBS system is set to 0 V and turned off before ECT, and to avoid sites near the DBS electrodes.

Conclusions

Electroconvulsive therapy may be an effective and safe treatment for DBS patients with MDD.
Structural deviations of the posterior fossa and the cerebellum and their cognitive links in a neurodevelopmental deletion syndrome
Authors: Sefik Esra , Li Yiheng , Sholar Brittney , Evans Lindsey , Pincus Jordan , Ammar Zeena , Murphy Melissa M. , Klaiman Cheryl , Saulnier Celine A. , White Stormi P. , Goldman-Yassen Adam Ezra , Guo Ying , Walker Elaine F. , Li Longchuan , Shultz Sarah , Mulle Jennifer G.
Published: March 2022

Background

High-impact genetic variants associated with neurodevelopmental disorders provide biologically defined entry points for etiological discovery. The 3q29 deletion (3q29Del) is one such variant that confers a ∼40-fold increased risk for schizophrenia, and a ∼30-fold increased risk for autism. However, the specific neural mechanisms underlying this link remain largely unknown.

Methods

Here, we report the firstin vivoquantitative neuroimaging study in 3q29Del individuals (N=24) and healthy controls (N=1,608) using structural MRI. Given prior reports of posterior fossa abnormalities in 3q29Del, we focus our investigation on the cerebellum and its primary tissue-types. Additionally, we compare the prevalence of cystic/cyst-like malformations of the posterior fossa between 3q29Del participants and controls, and examine the association between neuroanatomical findings and standardized behavioral measures to probe gene-brain-behavior relationships.

Results

3q29Del participants had smaller cerebellar cortex volumes than controls, both before and after correction for intracranial volume (ICV). 3q29Del participants also had larger cerebellar white matter volumes than controls following ICV-correction. The 3q29Del group displayed an elevated rate of posterior fossa arachnoid cysts and mega cisterna magna findings independent of cerebellar volume. Sex played a moderating role in a subset of findings. Cerebellar white matter volume was positively associated with visual-motor integration skills and cognitive ability, while cystic/cyst-like malformations yielded no behavioral link.

Conclusions

Abnormal development of posterior fossa structures may represent neuroimaging-based biomarkers in 3q29Del. Results reveal cerebellar associations with sensorimotor and cognitive deficits in 3q29Del and present a novel point of genetic convergence with cerebellar pathology reported in idiopathic forms of neurodevelopmental disease.
Network analysis of Differentially Expressed Genes (DEGs) identified in zebrafish after infection with Spring viremia of carp virus (SVCV) – an in silico approach
Authors: Guttula Praveen Kumar , Rather Mohd Asharf
Published: March 2022

Spring viremia of carp virus (SVCV) is a virus that belongs to family of spring viremia of carp (SVC) and frequently causes hemorrhagic symptoms in several types of cyprinids and causes severe economic and environmental losses. Therefore, the mechanism of the infection is not clearly understood. In this study, zebrafish was employed as the infection model to explore the pathogenesis of SVCV. 4 groups of zebrafish tissues were set and RNA sequencing (RNA-Seq) technology was employed to analyze the differentially expressed genes (DEGs) after SVCV-infection. A total of 360,971,498 clean reads were obtained from samples, 382 DEGs in the brain and 926 DEGs in the spleen were identified. These DEGs were annotated into three ontologies after gene ontology (GO) enrichment analysis. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed that these DEGs were primarily related to Influenza. A pathway and Herpes simplex infection pathway in brain and Tuberculosis and Toxoplasmosis pathways in spleen, and all of these pathways may be involved in response to pathogen invasion. The transcriptome analysis results demonstrated changes and tissue-specific influences caused by SVCV in vivo, which provided us with more information to understand the complex relationships between SVCV and its host.
Fluctuation-driven plasticity allows for flexible rewiring of neuronal assemblies
Authors: Devalle Federico , Roxin Alex
Published: March 2022

Synaptic connections in neuronal circuits are modulated by pre- and post-synaptic spiking activity. Heuristic models of this process of synaptic plasticity can provide excellent fits to results from in-vitro experiments in which pre- and post-synaptic spiking is varied in a controlled fashion. However, the plasticity rules inferred from fitting such data are inevitably unstable, in that given constant pre- and post-synaptic activity the synapse will either fully potentiate or depress. This instability can be held in check by adding additional mechanisms, such as homeostasis. Here we consider an alternative scenario in which the plasticity rule itself is stable. When this is the case, net potentiation or depression only occur when pre- and post-synaptic activity vary in time, e.g. when driven by time-varying inputs. We study how the features of such inputs shape the recurrent synaptic connections in models of neuronal circuits. In the case of oscillatory inputs, the resulting structure is strongly affected by the phase relationship between drive to different neurons. In large networks, distributed phases tend to lead to hierarchical clustering. Our results may be of relevance for understanding the effect of sensory-driven inputs, which are by nature time-varying, on synaptic plasticity, and hence on learning and memory.
A reduced-memory multi-layer perceptron with systematic network weights generated and trained through distribution hyper-parameters
Authors: Vinayak Neha , Ahmad Shandar
Published: March 2022

A multi-layer perceptron (MLP) consists of a number of forward-connected weights (Wijk) from each feeding layer node (nij) to the many initially equivalent nodes (ni+1,k) in the next layer. Exact a priori order and search space of these weights (Wijk) is random and prone to redundancy, irreproducibility and non-optimality. We demonstrate that a weight subspace (Wijk for each i and j), generated systematically using a statistical distribution with predefined breakpoints and Genetic algorithm-trained hyper-parameters substantially reduces the computational complexity of an MLP and produces comparable or better performance than similarly trained equivalent models with fully defined weights. This distribution based neural network (DBNN) provides a novel framework to create very large neural network models with currently prohibitive memory requirements.
Kv7 channel antagonists block glycine receptors
Authors: Lu Hsin-Wei , Romero Gabriel E. , Apostolides Pierre F. , Huang Hai , Trussell Laurence O.
Published: March 2022

XE991 (10,10-bis(4-pyridinylmethyl)-9(10H)-anthracenone) is currently the most widely used and specific antagonist of the Kv7 (KCNQ) family of K+ channels. We report an unexpected antagonistic effect of this drug on ionotropic glycine receptors. In recordings of synaptic transmission in two brainstem nuclei (the medial nucleus of the trapezoid body and the dorsal cochlear nucleus), 10 μM XE991, a concentration typical for Kv7 studies in brain tissue, inhibited evoked glycinergic inhibitory postsynaptic currents (IPSCs) without altering paired-pulse ratio, and also reduced the amplitude of glycinergic miniature IPSCs. These results are indicative of a direct effect of the drug on postsynaptic glycine receptors. XE991 also produced dose-dependent block of the response to exogenously applied glycine, to a degree comparable to the block of synaptic transmission. Moreover, the drug inhibited homomeric glycine receptors expressed on presynaptic membrane of the calyx of Held. The degree of block was independent of glycine concentration, suggesting an allosteric interaction. The effects of XE991 on glycine responses are not likely to reflect block of the glycine-activated Cl- channels themselves, because block was voltage independent, and because GABA-activated Cl- currents were resistant to XE991 at concentrations up to 100 µM. Linopirdine, but not retigabine, also antagonized glycine receptor currents. Given the prevalence of glycine receptor signaling in the brain, these observations should be taken into account in studies of the roles of Kv7 channels in neural circuit function and disease.
Amplification of Olfactory Signals by Anoctamin 9 is Essential for Mammalian Olfaction: a Risk Factor for the Covid-19-associated Anosmia
Authors: Kim Hyungsup , Kim Hyesu , Nguyen Luan Thien , Ha Taewoong , Lim Sujin , Kim Kyungmin , Kim Soon Ho , Han Kyungreem , Hyeon Seung Jae , Ryu Hoon , Park Yong Soo , Kim Sang Hyun , Kim In-Beom , Hong Gyu-Sang , Lee Seung Eun , Choi Yunsook , Cohen Lawrence B. , Oh Uhtaek
Published: March 2022

Sensing smells of foods, prey, or predators determines animal survival. Olfactory sensory neurons in the olfactory epithelium (OE) detect odorants, where cAMP and Ca2+ play a significant role in transducing odorant inputs to electrical activity. Here we show Anoctamin 9, a cation channel activated by cAMP/PKA pathway, is expressed in the OE and amplifies olfactory signals. Ano9- deficient mice had reduced olfactory behavioral sensitivity, electro-olfactogram signals, and neural activity in the olfactory bulb. In line with the difference in olfaction between birds and other vertebrates, chick ANO9 failed to respond to odorants, whereas chick CNGA2, a major transduction channel, showed greater responses to cAMP. Importantly, single-cell transcriptome data from Covid-19 patients revealed that Ano9 transcripts were markedly suppressed among genes in the olfactory signal pathway. The signal amplification by ANO9 is essential for mammalian olfactory transduction, whose downregulation may be a risk factor for the olfactory dysfunction in Covid-19 patients.
Bis(2-amino-3,5-dichloropyridinium) hexachloridostannate(IV) dihydrate
Authors: Ghallab Rochdi , Bougueria Hassiba , Merazig Hocine
Published: March 2022

The title hybrid compound, (C5H5N2Cl2)2[SnCl6]·2H2O, was synthesized and its structure was identified by single-crystal X-ray diffraction. The structure is non-polymeric (0D) in terms of containing isolated [SnCl6]2− polyhedra. The special position (0,0,0) of the SnIV atom in the crystal structure gives rise to a stacking structure with alternating cationic and anionic layers parallel to (001). The water molecules are intercalated between these layers, which are linked by cation–anion hydrogen bonds and dominant non-covalent interactions. The stability of the three-dimensional network for this compound is also discussed.
The impact of farm-level variables on federal crop insurance coverage selections
Authors: Boyd Mark , Belasco Eric
Published: March 2022

Purpose

This paper examines the relationship between farm-level variables related to cash flow and premium rates on federal crop insurance coverage selection.

Design/methodology/approach

Using farm-level data from the Agricultural Resource Management Survey (ARMS), the authors estimate a linear fixed effects model to evaluate the relationship between farm-level and regional variables and federal crop insurance coverage selections.

Findings

The authors find evidence indicating that expected cash flow plays an important role in coverage level decisions. For example, variables directly related to cash flow, such as higher costs, are associated with significant differences in coverage level selection, though the direction of the association is dependent on the type of costs, whether fixed or variable, while higher revenue higher acreage farms insure at higher coverage levels. In addition, higher premium costs are associated with lower coverage level selections, despite subsidy incentives.

Originality/value

This is the first paper that identifies a potential solution to the puzzling finding that farmers do not consistently maximize coverage level. This research points to the influence of credit constraints as playing a role in limiting coverage level selections.