bluuebunny/crossref_metadata_2025 huggingface dataset:
Activity pulses induce spontaneous flow reversals in viscoelastic environments
Authors: Plan Emmanuel L. C. VI M. , Yeomans Julia M. , Doostmohammadi Amin
Published: April 2021

Complex interactions between cellular systems and their surrounding extracellular matrices are emerging as important mechanical regulators of cell functions, such as proliferation, motility and cell death, and such cellular systems are often characterized by pulsating actomyosin activities. Here, using an active gel model, we numerically explore spontaneous flow generation by activity pulses in the presence of a viscoelastic medium. The results show that cross-talk between the activity-induced deformations of the viscoelastic surroundings and the time-dependent response of the active medium to these deformations can lead to the reversal of spontaneously generated active flows. We explain the mechanism behind this phenomenon based on the interaction between the active flow and the viscoelastic medium. We show the importance of relaxation time scales of both the polymers and the active particles and provide a phase space over which such spontaneous flow reversals can be observed. Our results suggest new experiments investigating the role of controlled pulses of activity in living systems ensnared in complex mircoenvironments.
Mosquito sound communication: are male swarms loud enough to attract females?
Authors: Feugère Lionel , Gibson Gabriella , Manoukis Nicholas C. , Roux Olivier
Published: April 2021

Given the unsurpassed sound sensitivity of mosquitoes among arthropods and the sound source power required for long-range hearing, we investigated the distance over which female mosquitoes detect species-specific cues in the sound of station-keeping mating swarms. A common misunderstanding, that mosquitoes cannot hear at long range because their hearing organs are ‘particle-velocity’ receptors, has clouded the fact that particle velocity is an intrinsic component of sound whatever the distance to the sound source. We exposed free-flyingAnopheles coluzziifemales to pre-recorded sounds of maleAn. coluzziiandAn. gambiae s.s.swarms over a range of natural sound levels. Sound levels tested were related to equivalent distances between the female and the swarm for a given number of males, enabling us to infer distances over which females might hear large male swarms. We show that females do not respond to swarm sound up to 48 dB sound pressure level (SPL) and that louder SPLs are not ecologically relevant for a swarm. Considering that swarms are the only mosquito sound source that would be loud enough to be heard at long range, we conclude that inter-mosquito acoustic communication is restricted to close-range pair interactions. We also showed that the sensitivity to sound in free-flying males is much enhanced compared to that of tethered ones.
Thermal and anticorrosion properties of polyurethane coatings derived from recycled polyethylene terephthalate and palm olein-based polyols
Authors: Adamu Abbas Ahmad , Muhamad Sarih Norazilawati , Gan Seng Neon
Published: April 2021

Polyols of palm olein/polyethylene terephthalate (PET) were synthesized by means of incorporating recycled PET from waste drinking bottles in different proportions into palm olein alkyd in the presence of ethylene glycol. The polyols were characterized by FTIR, and theirs hydroxyl value (OHV), acid value (AV) and viscosity were determined. The formulation of the polyurethane coating was carried out by dissolving the polyol in mixed solvent of cyclohexanone/tetrahydrofuran (THF) (4 : 1) followed by reacting 1 hydroxyl equivalent of the polyol with 1.2 equivalents of methylene diphenyldiisocyanate and 0.05% dibutyltin dilaurate (DBTDL) catalyst. The coating cured through the cross-linking reactions between hydroxyl and isocyanate groups. The formation of urethane linkages was established by FTIR spectroscopy. The set films were characterized by thermal analysis. To study their anticorrosion properties, polarization measurements and EIS in 3.5% NaCl solution were determined. The coatings displayed good thermal stability and anticorrosion properties which were supported by XRD analysis. The PU7 coating, with the highest proportion of PET (up to 15% w/w), displayed significantly improved thermal stability and anticorrosion properties. It is evident that the performance of the polyurethane (PU) coatings could be enhanced by the incorporation of PET.
Application strategies by selective medium treated with entomopathogenic bacteria
Serratia marcescens
and
Pseudomonas aeruginosa
as potential biocontrol against
Coptotermes curvignathus
Authors: Chin Kit Ling , H'ng Paik San , Lee Chuan Li , Wong Wan Zhen , Go Wen Ze , Khoo Pui San , Luqman Abdullah Chuah , Ashaari Zaidon
Published: April 2021

The success of microbial termiticides in controlling termites depends on the ability of microbes to grow in different media and the functionality of the microbes as a resistant barrier or toxic bait. This study was conducted to understand the mortality rate and behaviour changes of the subterranean termite
Coptotermes curvignathus
Holmgren introduced with different concentrations of
Serratia marcescens
strain LGMS 1 and
Pseudomonas aeruginosa
strain LGMS 3 using wood and soil as bacterial transfer medium. In general, higher concentration of bacteria in soil caused a reduction in tunnelling activity and wood consumption and an increase in mortality. However, application on wood revealed a different outcome. Wood treated with
S. marcescens
of 10
6
CFU ml
−1
concentration proved to be more efficient as bait than higher concentration applications as it caused a high mortality rate while still highly palatable for termites. Wood or soil treated with
S. marcescens
concentration higher than 10
9
CFU ml
−1
creates a high toxicity and repellent barrier for termites.
Pseudomonas aeruginosa
of 10
9
CFU ml
−1
concentrations applied on wood served as a slow-acting toxic bait. However, the ability for
S. marcescens
and
P. aeruginosa
to survive on wood is low, which made the bait unable to retain a useful level of toxicity for a long period of time and frequent reapplication is needed.
Harvesting strategies as evidence for 4000 years of camas (
Camassia quamash
) management in the North American Columbia Plateau
Authors: Carney Molly , Tushingham Shannon , McLaughlin Tara , d'Alpoim Guedes Jade
Published: April 2021

One of the greatest archaeological enigmas is in understanding the role of decision-making, intentionality and interventions in plant life cycles by foraging peoples in transitions to and from low-level food production practices. We bring together archaeological, palaeoclimatological and botanical data to explore relationships over the past 4000 years between people and camas (
Camassia quamash
), a perennial geophyte with an edible bulb common across the North American Pacific Northwest. In this region throughout the late Holocene, people began experimenting with selective harvesting practices through targeting sexually mature bulbs by 3500 cal BP, with bulb harvesting practices akin to ethnographic descriptions firmly established by 1000 cal BP. While we find no evidence that such interventions lead to a selection for larger bulbs or a reduction in time to maturity, archaeological bulbs do exhibit several other domestication syndrome traits. This establishes considerable continuity to human intervention into camas life cycles, but these dynamic relationships did not result in unequivocal morphological indications of domestication. This approach to tracking forager plant management practices offers an alternative explanatory framework to conventional management studies, supplements oral histories of Indigenous traditional resource management and can be applied to other vegetatively propagated species.
The geography and development of language isolates
Authors: Urban Matthias
Published: April 2021

This contribution theorizes the historical dynamics of so-called language isolates, languages which cannot be demonstrated to belong to any known language family. On the basis of a qualitative review of how isolates, language families or their branches lost territory to other languages through time, I develop a simple model for the genesis of isolates as a function of proximity to major geographical barriers, and pit it against an alternative view that sees them as one manifestation of linguistic diversity generally. Using a variety of statistical techniques, I test both accounts quantitatively against a worldwide dataset of language locations and distances to geographical barriers, and find support for the position that views language isolates as one manifestation of linguistic diversity generally. However, I caution that different processes which are not necessarily mutually exclusive may have shaped the present-day distribution of language isolates. These may form elements of a broader theory of language isolates in particular and language diversity in general.
Common kinematic synergies of various human locomotor behaviours
Authors: Huang Bo , Xiong Caihua , Chen Wenbin , Liang Jiejunyi , Sun Bai-Yang , Gong Xuan
Published: April 2021

Humans show a variety of locomotor behaviours in daily living, varying in locomotor modes and interaction styles with the external environment. However, how this excellent motor ability is formed, whether there are some invariants underlying various locomotor behaviours and simplifying their generation, and what factors contribute to the invariants remain unclear. Here, we find three common kinematic synergies that form the six joint motions of one lower limb during walking, running, hopping and sitting-down-standing-up (movement variance accounted for greater than 90%), through identifying the coordination characteristics of 36 lower limb motor tasks in diverse environments. This finding supports the notion that humans simplify the generation of various motor behaviours through re-using several basic motor modules, rather than developing entirely new modules for each behaviour. Moreover, a potential link is also found between these synergies and the unique biomechanical characteristics of the human musculoskeletal system (muscular-articular connective architecture and bone shape), and the patterns of inter-joint coordination are consistent with the energy-saving mechanism in locomotion by using biarticular muscles as efficient mechanical energy transducers between joints. Altogether, our work helps understand the formation mechanisms of human locomotion from a holistic viewpoint and evokes inspirations for the development of artificial limbs imitating human motor ability.
Puckering and wrinkling in a growing composite ring
Authors: Michaels T. C. T. , Kusters R. , Mahadevan L.
Published: April 2021

Pattern formation driven by differential strain in constrained elastic systems is a common motif in many technological and biological systems. Here we introduce a biologically motivated case of elastic patterning that allows us to explore the conditions for the existence of local puckering and global wrinkling patterns: a soft growing composite ring adhered elastically to a constraining rigid ring. We explore how differential growth of the soft ring and the elastic resistance to shear and stretching deformations induced by soft adherence lead to a range of phenomena that include uniform aperture-like modes, localized puckers that are Nambu–Goldstone-like modes and global wrinkles in the system. Our analysis combines computer simulations of a discrete rod model with a nonlinear stability analysis of the differential equations in the continuum limit. We provide phase diagrams and scaling relations that reveal the nature and extent of the deformation patterns. Overall, our study reveals how geometry and mechanics conspire to yield a rich phenomenology that could serve as a guide to the design of programmable localized elastic deformations while being relevant for the mechanical basis of biological morphogenesis.
Species packing and the latitudinal gradient in beta-diversity
Authors: Cao Ke , Condit Richard , Mi Xiangcheng , Chen Lei , Ren Haibao , Xu Wubing , Burslem David F. R. P. , Cai Chunrong , Cao Min , Chang Li-Wan , Chu Chengjin , Cui Fuxin , Du Hu , Ediriweera Sisira , Gunatilleke C. S. V. , Gunatilleke I. U. A. N. , Hao Zhanqing , Jin Guangze , Li Jinbo , Li Buhang , Li Yide , Liu Yankun , Ni Hongwei , O'Brien Michael J. , Qiao Xiujuan , Shen Guochun , Tian Songyan , Wang Xihua , Xu Han , Xu Yaozhan , Yang Libing , Yap Sandra L. , Lian Juyu , Ye Wanhui , Yu Mingjian , Su Sheng-Hsin , Chang-Yang Chia-Hao , Guo Yili , Li Xiankun , Zeng Fuping , Zhu Daoguang , Zhu Li , Sun I-Fang , Ma Keping , Svenning Jens-Christian
Published: April 2021

The decline in species richness at higher latitudes is among the most fundamental patterns in ecology. Whether changes in species composition across space (beta-diversity) contribute to this gradient of overall species richness (gamma-diversity) remains hotly debated. Previous studies that failed to resolve the issue suffered from a well-known tendency for small samples in areas with high gamma-diversity to have inflated measures of beta-diversity. Here, we provide a novel analytical test, using beta-diversity metrics that correct the gamma-diversity and sampling biases, to compare beta-diversity and species packing across a latitudinal gradient in tree species richness of 21 large forest plots along a large environmental gradient in East Asia. We demonstrate that after accounting for topography and correcting the gamma-diversity bias, tropical forests still have higher beta-diversity than temperate analogues. This suggests that beta-diversity contributes to the latitudinal species richness gradient as a component of gamma-diversity. Moreover, both niche specialization and niche marginality (a measure of niche spacing along an environmental gradient) also increase towards the equator, after controlling for the effect of topographical heterogeneity. This supports the joint importance of tighter species packing and larger niche space in tropical forests while also demonstrating the importance of local processes in controlling beta-diversity.
Craniofacial development illuminates the evolution of nightbirds (Strisores)
Authors: Navalón Guillermo , Nebreda Sergio M. , Bright Jen A. , Fabbri Matteo , Benson Roger B. J. , Bhullar Bhart-Anjan , Marugán-Lobón Jesús , Rayfield Emily J.
Published: April 2021

Evolutionary variation in ontogeny played a central role in the origin of the avian skull. However, its influence in subsequent bird evolution is largely unexplored. We assess the links between ontogenetic and evolutionary variation of skull morphology in Strisores (nightbirds). Nightbirds span an exceptional range of ecologies, sizes, life-history traits and craniofacial morphologies constituting an ideal test for evo-devo hypotheses of avian craniofacial evolution. These morphologies include superficially ‘juvenile-like’ broad, flat skulls with short rostra and large orbits in swifts, nightjars and allied lineages, and the elongate, narrow rostra and globular skulls of hummingbirds. Here, we show that nightbird skulls undergo large ontogenetic shape changes that differ strongly from widespread avian patterns. While the superficially juvenile-like skull morphology of many adult nightbirds results from convergent evolution, rather than paedomorphosis, the divergent cranial morphology of hummingbirds originates from an evolutionary reversal to a more typical avian ontogenetic trajectory combined with accelerated ontogenetic shape change. Our findings underscore the evolutionary lability of cranial growth and development in birds, and the underappreciated role of this aspect of phenotypic variability in the macroevolutionary diversification of the amniote skull.
Detection of SARS-CoV-2 specific IgA in the human milk of COVID-19 vaccinated, lactating health care workers
Authors: Valcarce Vivian , Stafford Lauren S. , Neu Josef , Cacho Nicole , Parker Leslie , Mueller Martina , Burchfield David J , Li Nan , Larkin Joseph
Published: April 2021

Importance

In 2019, a deadly virus known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), responsible for COVID-19, emerged. In December 2020, two mRNA-based COVID-19 vaccines were approved for use in the United States (US) which provide immunity to those receiving the vaccine. Maternally derived antibodies are a key element of infants’ immunity. Certain vaccines given to pregnant and lactating mothers provide immunity to infants through transmission across the placenta, umbilical cord (IgG) and human milk (IgA). Human milk produced by mothers with a history of COVID-19 infection contains SARS-CoV-2 IgA and IgG.

Objective

To determine whether SARS-CoV-2 specific immunoglobulins are found in human milk after the COVID-19 vaccination, and to characterize the types of immunoglobulins present.

Design, setting, and participants

This is a prospective observational study conducted at Shands Hospital, University of Florida from December 2020 to March 2021. Twenty-two lactating healthcare workers who received the SARS-CoV-2 mRNA vaccine (Pfizer/BioNtech or Moderna) made up the sample group. Plasma and human milk were collected at three-time points (pre-vaccination, post-first vaccine dose, and post-second vaccine dose). SARS-CoV-2 specific IgA and IgG in human milk and in plasma were measured by ELISA. Maternal demographics was compiled.

Exposures

Pfizer/BioNtech or Moderna vaccination.

Main outcome and measure

Levels of SARS-CoV-2 IgA and IgG in human milk and plasma.

Results

We found significant secretion of SARS-CoV-2 specific IgA and IgG in human milk and plasma after SARS-CoV-2 vaccination.

Conclusions and relevance

Our results show that the mRNA-based COVID-19 vaccines induce SARS-CoV-2 specific IgA and IgG secretion in human milk. Further studies are needed to determine the duration of this immune response, its capacity to neutralize the COVID-19 virus, the transfer of passive immunity to breastfeeding infants, and the potential therapeutic use of human milk IgA to combat SARS-CoV-2 infections and COVID-19.

KEY POINTS

Question

Is there SARS-CoV-2 specific IgA in the human milk of lactating women after COVID-19 vaccination?

Findings

In this prospective observational study that included 22 lactating women, we found SARS-CoV-2 specific IgA in the human milk in response to the COVID-19 vaccination series. There is statistically significant secretion of SARS-CoV-2 IgA in human milk after mRNA COVID-19 vaccination series completion (p < 0.0001).

Meaning

Newborn immunologic defense is present but immature. SARS-CoV-2 IgA secreted in the human milk could potentially provide COVID-19 protection to nursing infants. These results could guide a strategy for SARS-CoV-2 vaccination among lactating women.
Detection of SARS-CoV-2 variant 501Y.V2 in Comoros Islands in January 2021
Authors: Agoti Charles N. , Githinji George , Mohammed Khadija S. , Lambisia Arnold L. , de Laurent Zaydah R. , Mburu Maureen W. , Ong’era Edidah M. , Morobe John M. , Otieno Edward , Azali Hamza Abdou , Abdallah Kamal Said , Diarra Abdoulaye , Yahaya Ali Ahmed , Athanasius Dratibi Fred , Moeletsi Nicksy Gumede , Tsofa Benjamin , Bejon Philip , Borus Peter , Nokes D. James , Ochola-Oyier Isabella
Published: April 2021

Phylogenetic analysis of six SARS-CoV-2 genomes collected from the Comoros islands confirmed local circulation of the 501Y.V2 variant of concern during the country’s first major SARS-CoV-2 wave in January 2021. These findings demonstrate the importance of SARS-CoV-2 genomic surveillance and have implications for ongoing COVID-19 control strategies on the islands.

Article summary line

Circulation of SARS-CoV-2 501Y.V2 variant of concern in the Comoros Islands during a major COVID-19 infection wave in January 2021
The emergence of SARS-CoV-2 variant(s) and its impact on the prevalence of COVID-19 cases in Nabatieh region, Lebanon
Authors: Noureddine Fatima Y. , Chakkour Mohamed , El Roz Ali , Reda Jana , Al Sahily Reem , Assi Ali , Joma Mohamed , Salami Hassan , Hashem Sadek J. , Harb Batoul , Salami Ali , Ghssein Ghassan
Published: April 2021

Background

An outbreak of an unknown respiratory illness caused by a novel corona-virus, SARS-CoV-2, emerged in the city of Wuhan in Hubei province, China, in December 2019 and was referred to as coronavirus disease-2019 (COVID-19). Soon after, it was declared as a global pandemic by the World Health Organization (WHO) in March 2020. SARS-CoV-2 mainly infects the respiratory tract with different outcomes ranging from asymptomatic infection to severe critical illness leading to death. Different SARS-CoV-2 variants are emerging of which three have raised concerns worldwide due to their high transmissibility among populations.

Objective

To study the prevalence of COVID-19 in the region of Nabatieh - South Lebanon during the past year and assess the presence of SARS-CoV-2 variants and their effect on the spread of infection during times of lock-down. Methods: In our study, 37,474 nasopharyngeal swab samples were collected and analyzed for the detection of SARS-CoV-2 virus in suspected patients attending a tertiary health care center in South Lebanon during the period between March 16, 2020 and February 21, 2021.

Results

Results demonstrated a variation in the prevalence rates ranging from less than 1% during full lockdown of the country to 8.4% upon easing lockdown restrictions and reaching 27.5% after the holidays and 2021 New Year celebrations. Interestingly, a new variant(s) appeared starting January 2021 with a significant positive association between the prevalence of positive tests and the percentage of the variant(s).

Conclusion

Our results indicate that the lockdown implemented by the Lebanese officials presented an effective intervention to contain COVID-19 spread. Our study also showed that lifting lockdown measures during the holidays, which allowed indoor crowded gatherings to occur, caused a surge in COVID-19 cases and rise in the mortality rates nationwide. More importantly, we confirmed the presence of a highly transmissible SARS-CoV-2 variant(s) circulating in the Lebanese community, at least since January 2021 onwards.
Growth charts for individualized evaluation of brain morphometry for preschool children
Authors: Zhang Hongxi , Li Jia , Su Xiaoli , Hu Yang , Liu Tianmei , Ni Shaoqing , Li Haifeng , Zuo Xi-Nian , Fu Junfen , Yuan Ti-Fei , Yang Zhi
Published: April 2021

Brain development from 1 to 6 years-of-age anchors the rapid development of a wide range of functional capabilities. However, quantitative growth charts of typical development during this age period are lacking, preventing the identification of early brain abnormalities. Here we characterize the time-dependent individual differences of cortical thickness and subcortical volume in 340 typically developing children and construct regional growth curves for these brain morphological measures. The growth curves reflect four types of time-dependence for cortical thickness and subcortical volume metrics. At the individual level, the growth curve model provides percentiles for each brain region’s cortical thickness or volume during ages 1 to 6, allowing for individualized inferences of brain developmental status relative to the same-age population. The growth curves further demonstrate clinical utility potentials by identifying children with developmental speech and language disorders, achieving high accuracies on data collected on both 1.5T and 3T scanners. Our results fill the knowledge gap in brain morphometrics in a critical development period and provide an avenue for individualized brain developmental status evaluation, with demonstrated sensitivity and generalizability.
Volumetric lung cancer screening reduces unnecessary low-dose computed tomography scans: results from a single-centre prospective trial on 4,119 subjects
Authors: Milanese Gianluca , Sabia Federica , Ledda Roberta Eufrasia , Sestini Stefano , Marchianò Alfonso Vittorio , Sverzellati Nicola , Pastorino Ugo
Published: April 2021

Purpose

To compare low-dose computed tomography (LDCT) outcome and volume-doubling time (VDT) derived from measured volume (MV) and estimated volume (EV) of pulmonary nodules (PN) detected in a single-centre lung cancer screening trial.

Materials and Methods

MV, EV and VDT were obtained for prevalent pulmonary nodules detected at the baseline round of the bioMILD trial. LDCT outcome (based on bioMILD thresholds) and VDT categories were simulated on a PN- and a screenees-based analysis. Weighted Cohen’s kappa test was used to assess the agreement between diagnostic categories as per MV and EV.

Results

1,583 screenees displayed 2,715 pulmonary nodules. On a PN-based analysis 40.1% PNs would have been included in different LDCT categories if measured by MV or EV. Agreement between MV and EV was moderate (κ = 0.49) and fair (κ = 0.37) for LDCT outcome and VDT categories, respectively.

On a screenees-based analysis, 46% pulmonary nodules would have been included in different LDCT categories if measured by MV or EV. Agreement between MV and EV was moderate (κ = 0.52) and fair (κ = 0.34) for LDCT outcome and VDT categories, respectively.

Conclusions

Within a simulated lung cancer screening based on recommendation by estimated volumetry, the number of LDCT performed for the evaluation of pulmonary nodules would be higher as compared to the prospective volumetric management.
The Impact of HPV DNA/p16 in Laryngeal/Hypopharyngeal Cancer: a Systematic Review and Meta-analysis
Authors: Van der Elst Sarah , Russo Daniel P. , Mumaw Derek , Wotman Michael , Tham Tristan
Published: April 2021

Background

This meta-analysis seeks to investigate the association between HPV and p16 status with overall survival in laryngeal and hypopharyngeal carcinoma.

Methods

Medline, Scopus, EMBASE, and the Cochrane Library were used to identify studies for inclusion. Abstracts that discussed HPV/p16 status and prognosis in laryngeal or hypopharyngeal carcinoma were included. Next, full-text articles were screened and included based upon a checklist established a priori. Pooled hazard ratios for overall survival were generated using a random effects model. RevMan 5.3, Meta Essentials, and OpenMeta[Analyst] were used for statistical analysis.

Results

Thirteen studies published between 2014 and 2019 with sample sizes ranging from 31 to 9,656 were selected for inclusion in this meta-analysis. The pooled data demonstrated that p16 status was not significantly associated with OS in either laryngeal or hypopharyngeal carcinoma with HRs of 1.03 (95% CI: 0.73–1.45; p = 0.88) and 1.02 (95% CI: 0.55–1.86; p = 0.96), respectively. The pooled data showed that HPV status was predictive of OS in laryngeal cancer with 0.63 (95% CI: 0.41–0.97; p = 0.03).

Conclusions

Our results suggest that p16-positivity does not provide a survival benefit in LC and HPC. This is in contrast to studies in the oropharynx, where p16 status is a standard proxy for HPV infection and HPV infection is associated with improved prognosis.
Vaccination boosts protective responses and counters SARS-CoV-2-induced pathogenic memory B cells
Authors: Mishra Pankaj Kumar , Bruiners Natalie , Ukey Rahul , Datta Pratik , Onyuka Alberta , Handler Deborah , Hussain Sabiha , Honnen William , Singh Sukhwinder , Guerrini Valentina , Yin Yue , Dewald Hannah , Choudhary Alok , Horton Daniel B. , Barrett Emily S. , Roy Jason , Weiss Stanley H. , Fitzgerald-Bocarsly Patricia , Blaser Martin J. , Carson Jeffrey L. , Panettieri Reynold A. , Lardizabal Alfred , Chang Theresa Li-Yun , Pinter Abraham , Gennaro Maria Laura
Published: April 2021

Much is to be learned about the interface between immune responses to SARS-CoV-2 infection and vaccination. We monitored immune responses specific to SARS-CoV-2 Spike Receptor-Binding-Domain (RBD) in convalescent individuals for eight months after infection diagnosis and following vaccination. Over time, neutralizing antibody responses, which are predominantly RBD specific, generally decreased, while RBD-specific memory B cells persisted. RBD-specific antibody and B cell responses to vaccination were more vigorous than those elicited by infection in the same subjects or by vaccination in infection-naïve comparators. Notably, the frequencies of double negative B memory cells, which are dysfunctional and potentially pathogenic, increased in the convalescent subjects over time. Unexpectedly, this effect was reversed by vaccination. Our work identifies a novel aspect of immune dysfunction in mild/moderate COVID-19, supports the practice of offering SARS-CoV-2 vaccination regardless of infection history, and provides a potential mechanistic explanation for the vaccination-induced reduction of “Long-COVID” symptoms.
One Health Investigation of SARS-CoV-2 Infection and Seropositivity among Pets in Households with Confirmed Human COVID-19 Cases — Utah and Wisconsin, 2020
Authors: Goryoka Grace W. , Cossaboom Caitlin M. , Gharpure Radhika , Dawson Patrick , Tansey Cassandra , Rossow John , Mrotz Victoria , Rooney Jane , Torchetti Mia , Loiacono Christina M. , Killian Mary L. , Jenkins-Moore Melinda , Lim Ailam , Poulsen Keith , Christensen Dan , Sweet Emma , Peterson Dallin , Sangster Anna L. , Young Erin L. , Oakeson Kelly F. , Taylor Dean , Price Amanda , Kiphibane Tair , Klos Rachel , Konkle Darlene , Bhattacharyya Sanjib , Dasu Trivikram , Chu Victoria T. , Lewis Nathaniel M. , Queen Krista , Zhang Jing , Uehara Anna , Dietrich Elizabeth A. , Tong Suxiang , Kirking Hannah L. , Doty Jeffrey R. , Murrell Laura S. , Spengler Jessica R. , Straily Anne , Wallace Ryan , Behravesh Casey Barton
Published: April 2021

Background

Approximately 67% of U.S. households have pets. Limited data are available on SARS-CoV-2 in pets. We assessed SARS-CoV-2 infection in pet cohabitants as a sub-study of an ongoing COVID-19 household transmission investigation.

Methods

Mammalian pets from households with ≥1 person with laboratory-confirmed COVID-19 were eligible for inclusion from April–May 2020. Demographic/exposure information, oropharyngeal, nasal, rectal, and fur swabs, feces, and blood were collected from enrolled pets and tested by rRT-PCR and virus neutralization assays.

Findings

We enrolled 37 dogs and 19 cats from 34 of 41 eligible households. All oropharyngeal, nasal, and rectal swabs tested negative by rRT-PCR; one dog’s fur swabs (2%) tested positive by rRT-PCR at the first animal sampling. Among 47 pets with serological results from 30 households, eight (17%) pets (4 dogs, 4 cats) from 6 (20%) households had detectable SARS-CoV-2 neutralizing antibodies. In households with a seropositive pet, the proportion of people with laboratory-confirmed COVID-19 was greater (median 79%; range: 40–100%) compared to households with no seropositive pet (median 37%; range: 13–100%) (p=0.01). Thirty-three pets with serologic results had frequent daily contact (≥1 hour) with the human index patient before the person’s COVID-19 diagnosis. Of these 33 pets, 14 (42%) had decreased contact with the human index patient after diagnosis and none (0%) were seropositive; of the 19 (58%) pets with continued contact, 4 (21%) were seropositive.

Interpretations

Seropositive pets likely acquired infection from humans, which may occur more frequently than previously recognized. People with COVID-19 should restrict contact with animals.

Funding

Centers for Disease Control and Prevention, U.S. Department of Agriculture
Genetic control of fetal placental genomics contributes to development of health and disease
Authors: Bhattacharya Arjun , Freedman Anastasia N. , Avula Vennela , Harris Rebeca , Liu Weifang , Pan Calvin , Lusis Aldons J. , Joseph Robert M. , Smeester Lisa , Hartwell Hadley J. , Kuban Karl C.K. , Marsit Carmen J. , Li Yun , O’Shea T. Michael , Fry Rebecca C. , Santos Hudson P.
Published: April 2021

As the master regulator in utero, the placenta is core to the Developmental Origins of Health and Disease (DOHaD) hypothesis but is historically understudied. To identify placental gene-trait associations (GTAs) across the life course, we performed distal mediator-enriched transcriptome-wide association studies (TWAS) for 40 traits, integrating placental multi-omics from the Extremely Low Gestational Age Newborn Study. At P < 2.5 × 10−6, we detected 248 GTAs, mostly for neonatal and metabolic traits, across 176 genes, enriched for cell growth and immunological pathways. In aggregate, genetic effects mediated by placental expression significantly explained 4 early-life traits but no later-in-life traits. 89 GTAs showed significant mediation through distal genetic variants, identifying hypotheses for distal regulation of GTAs. Investigation of one hypothesis in human placenta-derived choriocarcinoma cells showed that knockdown of mediator gene EPS15 upregulated predicted targets SPATA13 and FAM214A, both associated with waist-hip ratio in TWAS, and multiple genes involved in metabolic pathways. These results suggest profound health impacts of placental genomic regulation in developmental programming across the life course.
The effect of heat events on prehospital and retrieval service utilisation in rural and remote areas: a scoping review
Authors: O’Donnell Elen , Honan Bridget , Quilty Simon , Schultz Rebecca
Published: April 2021

Introduction

It is well established that heatwaves increase demand for emergency transport in metropolitan areas, however little is known about the impact of heat events on demand for prehospital retrieval services in rural and remote areas, or how heatwaves are defined in this context.

Inclusion criteria

Papers were eligible for inclusion if they reported on the impact of a heat event on the activity of a prehospital and retrieval service in a rural or remote area.

Methods

A search of PubMed, Cochrane, Science Direct, CINAHL and Google Scholar databases was undertaken on 18 August 2020, using search terms related to emergency medical transport, extreme heat and rural or remote. Data relevant to the impact of heat on retrieval service activity was extracted, as well as definitions of extreme heat.

Results

Two papers were identified, both from Australia. Both found that heat events increased the number of road ambulance call-outs. Both studies used the Excess Heat Factor to define heatwave periods of interest.

Conclusions

This review found almost no primary literature on demand for prehospital retrieval services in rural and remote areas, and no data specifically related to aeromedical transport. The research did recognise the disproportionate impact of heat-related increase in service demand on rural and regional health services. With the effects of climate change already being felt, there is an urgent need for more research and action in this area.
Recombinant binder of sperm protein1 (rec-BSP1) as a potent fertility factor mediates its effect on spermatozoa and production of blastocysts in buffalo
Authors: Bag Sudam , Ansari Shama , Turuk Alka , Mahanandia Nimai Charan , Saini Sikander , Biswal Satya Kumar , Singh Sandeep Kumar , Malik Praveen , Kumar Satish , Malakar Dhruba
Published: April 2021

Objective

To understand the effect of recombinant BSP1 (rec-BSP1) onin vitrocapacitation of sperm and fertilization study

Method(s)

Articles were screened for reports including rec-BSP1, Capacitation,in vitrofertilization

Intervention

None

Main Outcome Measure(s)

Reproductive outcomes, effect on gametes and embryos

Result(s)

Here we report an optimization of condition for rec-BSP1 production which was used forin vitrocapacitation and enhancement of buffalo embryo production. The sequence of the protein was used for multiple sequence alignment which has 99% similarity with PDC 109 protein. The expression of rec-BSP1 was carried out successfully with 1 mM IPTG at 160C for 22 hrs and purified it in soluble form. The structure of rec-BSP1 was generated using 3D modelling and analysed its mode of binding with heparin and PC by molecular docking and the structural stability of rec-BSP1-PC and rec-BSP1-heparin complexes by using molecular dynamic (MD) simulation. The effect of rec-BSP1 was observed onin vitrocapacitation of spermatozoa and buffalo blastocyst production. It was found that the rec-BSP1 enhanced the sperm motility at a concentration of 50 μg/ml for 1 h of incubation without having any detrimental effect on the sperm morphology and a significant increase in blastocyst production at concentration of 50 μg/ml rec-BSP1. Hence this finding represents a new insight and advance the prospective approach to develop a potential fertility factor in reproduction.

Conclusion(s)

The purified rec-BSP1 may enhance on male fertility and mediated its effect onin vitroblastocyst production in buffalo.
Cortico-Fugal Regulation of Predictive Coding
Authors: Lesicko Alexandria M.H. , Angeloni Christopher F. , Blackwell Jennifer M. , De Biasi Mariella , Geffen Maria N.
Published: April 2021

Sensory systems must account for both contextual factors and prior experience to adaptively engage with the dynamic external environment. In the central auditory system, neurons modulate their responses to sounds based on statistical context. These response modulations can be understood through a hierarchical predictive coding lens: responses to repeated stimuli are progressively decreased, in a process known as repetition suppression, whereas unexpected stimuli produce a prediction error signal. Prediction error incrementally increases along the auditory hierarchy from the inferior colliculus (IC) to the auditory cortex (AC), suggesting that these regions may engage in hierarchical predictive coding. A potential substrate for top-down predictive cues is the massive set of descending projections from the auditory cortex to subcortical structures, although the role of this system in predictive processing has never been directly assessed. We tested the effect of optogenetic inactivation of the auditory cortico-collicular feedback in awake mice on responses of IC neurons to stimuli designed to test prediction error and repetition suppression. Inactivation of the cortico-collicular pathway led to a decrease in prediction error in IC. Repetition suppression was unaffected by cortico-collicular inactivation, suggesting that this metric may reflect fatigue of bottom-up sensory inputs rather than predictive processing. We also discovered populations of IC neurons that exhibit repetition enhancement, a sequential increase in firing with stimulus repetition. Cortico-collicular inactivation led to a decrease in repetition enhancement in the central nucleus of IC, suggesting that it is a top-down phenomenon. Negative prediction error, a stronger response to a tone in a predictable rather than unpredictable sequence, was suppressed in shell IC units during cortico-collicular inactivation. These changes in predictive coding metrics arose from bidirectional modulations in the response to the standard and deviant contexts, such that neurons in IC responded more similarly to each context in the absence of cortical input. We also investigated how these metrics compare between the anesthetized and awake states by recording from the same neurons under both conditions. We found that metrics of predictive coding and deviance detection differ depending on the anesthetic state of the animal, with negative prediction error emerging in the central IC and repetition enhancement and prediction error being more prevalent in the absence of anesthesia. Overall, our results demonstrate that the auditory cortex provides cues about the statistical context of sound to subcortical brain regions via direct feedback, regulating processing of both prediction and repetition.
Selection for or against Escape from Nonsense Mediated Decay is a Novel Signature for the Detection of Cancer Genes
Authors: Kumar Runjun D. , Burns Briana A. , Vandeventer Paul J. , Luna Pamela N. , Shaw Chad A.
Published: April 2021

Escape from nonsense mediated decay (NMD-) can produce activated or inactivated gene products, and bias in rates of escape can identify functionally important genes in germline disease. We hypothesized that the same would be true of cancer genes, and tested for NMD- bias within The Cancer Genome Atlas pan-cancer somatic mutation dataset. We identify 29 genes that show significantly elevated or suppressed rates of NMD-. This novel approach to cancer gene discovery reveals genes not previously cataloged as potentially tumorigenic, and identifies many potential driver mutations in known cancer genes for functional characterization.
Genetic architecture of floral traits in bee- and hummingbird-pollinated sister species ofAquilegia(columbine)
Authors: Edwards Molly B. , Choi Gary P. T. , Derieg Nathan J. , Min Ya , Diana Angie C. , Hodges Scott A. , Mahadevan L. , Kramer Elena M. , Ballerini Evangeline S.
Published: April 2021

Interactions with animal pollinators have helped shape the stunning diversity of flower morphologies across the angiosperms. A common evolutionary consequence of these interactions is that some flowers have converged on suites of traits, or pollination syndromes, that attract and reward specific pollinator groups. Determining the genetic basis of these floral pollination syndromes can help us understand the processes that contributed to the diversification of the angiosperms. Here, we characterize the genetic architecture of a bee-to-hummingbird pollination shift inAquilegia(columbine) using QTL mapping of 17 floral traits encompassing color, nectar composition, and organ morphology. In this system, we find that the genetic architectures underlying differences in floral color are quite complex, and we identify several likely candidate genes involved in anthocyanin and carotenoid floral pigmentation. Most morphological and nectar traits also have complex genetic underpinnings; however, one of the key floral morphological phenotypes, nectar spur curvature, is shaped by a single locus of large effect.
Maintenance of Bound or Independent Features in Visual Working Memory is Task-dependent
Authors: Cao Ruoyi , Pertzov Yoni , Gao Zaifeng , Shen Mowei , Deouell Leon Y.
Published: April 2021

Over the last decade, seemingly conflicting results were obtained regarding the question of whether features of an object are stored separately, or bound together, in visual working memory. Many of these studies are based on an implicit assumption about a default, or fixed, mode of working memory storage. In contrast, here we asked whether the anticipated memory probes used in a given experiment might determine the format in which information is maintained in working memory, consistent with its task-oriented function. In order to test this flexible maintenance hypothesis, we recorded EEG while subjects performed a delayed-match-to-sample task with different requirements and load. In Experiment 1, by contrasting conditions with and without the requirement of maintaining bound features, we found significant differences in EEG signals recorded in central-parietal channels while controlling for differences in visual stimulation. Such difference was confirmed by multivariate pattern analysis (MVPA). Moreover, behavior results, topographical distributions and cross-contrast MVPA decoding jointly suggested that this effect is not the same as task load effect. These results were confirmed in Experiment 2 with an independent group of subjects with the same paradigm, providing reliable evidence that the format of object maintenance in visual working memory could be flexibly shaped by the current task.
Cross-dataset reproducibility of human retinotopic maps
Authors: Himmelberg Marc M. , Kurzawski Jan W. , Benson Noah C. , Pelli Denis G. , Carrasco Marisa , Winawer Jonathan
Published: April 2021

Population receptive field (pRF) models fit to fMRI data are used to non-invasively measure retinotopic maps in human visual cortex, and these maps are a fundamental component of visual neuroscience experiments. Here, we examined the reproducibility of retinotopic maps across two datasets: a newly acquired retinotopy dataset from New York University (NYU) (n=44) and a public dataset from the Human Connectome Project (HCP) (n=181). Our goal was to assess the degree to which pRF properties are similar across datasets, despite substantial differences in their experimental protocols. The two datasets simultaneously differ in their stimulus apertures, participant pool, fMRI protocol, MRI field strength, and preprocessing pipeline. We assessed the cross-dataset reproducibility of the two datasets in terms of the similarity of vertex-wise pRF estimates and in terms of large-scale polar angle asymmetries in cortical magnification. Within V1, V2, V3, and hV4, the group-median NYU and HCP vertex-wise polar angle estimates were nearly identical. Both eccentricity and pRF size estimates were also strongly correlated between the two datasets, but with a slope different from 1; the eccentricity and pRF size estimates were systematically greater in the NYU data. Next, to compare large-scale map properties, we quantified two polar angle asymmetries in V1 cortical magnification previously identified in the HCP data. The NYU dataset confirms earlier reports that more cortical surface area represents horizontal than vertical visual field meridian, and lower than upper vertical visual field meridian. Together, our findings show that the retinotopic properties of V1, V2, V3, and hV4 can be reliably measured across two datasets, despite numerous differences in their experimental design. fMRI-derived retinotopic maps are reproducible because they rely on an explicit computational model of the fMRI response. In the case of pRF mapping, the model is grounded in physiological evidence of how visual receptive fields are organized, allowing one to quantitatively characterize the BOLD signal in terms of stimulus properties (i.e., location and size). The new NYU Retinotopy Dataset will serve as a useful benchmark for testing hypotheses about the organization of visual areas and for comparison to the HCP 7T Retinotopy Dataset.
Two tales of one neural link predict blind individual’s Braille reading proficiency
Authors: Wang Ruxue , Gong Jiangtao , Zhao Chenying , Xu Yingqing , Hong Bo
Published: April 2021

Natural Braille reading, a demanding cognitive skill, poses a huge challenge for the brain network of the blind. Here, with behavioral measurement and functional MRI imaging data, we pinpointed the neural pathway and investigated the neural mechanisms of individual differences in Braille reading in late blindness. Using resting state fMRI, we identified a distinct neural link between the higher-tier ‘visual’ cortex—the lateral occipital cortex (LOC), and the inferior frontal cortex (IFC) in the late blind brain, which is significantly stronger than sighted controls. Individual Braille reading proficiency positively correlated with the left-lateralized LOC-IFC functional connectivity. In a natural Braille reading task, we found an enhanced bidirectional information flow with a stronger top-down modulation of the IFC-to-LOC effective connectivity. Greater top-down modulation contributed to higher Braille reading proficiency via a broader area of task-engaged LOC. Together, we established a model to predict Braille reading proficiency, considering both functional and effective connectivity of the LOC-IFC pathway. This ‘two-tale’ model suggests that developing the underpinning neural circuit and the top-down cognitive strategy contributes uniquely to superior Braille reading performance.

SIGNIFICANCE STATEMENT

For late blind humans, one of the most challenging cognitive skills is natural Braille reading. However, little is known about the neural mechanisms of significant differences in individual Braille reading performance. Using functional imaging data, we identified a distinct neural link between the left lateral occipital cortex (LOC) and the left inferior frontal cortex (IFC) for natural Braille reading in the late blind brain. To better predict individual Braille reading proficiency, we proposed a linear model with two variables of the LOC-IFC link: the resting-state functional connectivity and the task-engaged top-down effective connectivity. These findings suggest that developing the underpinning neural pathway and the top-down cognitive strategy contributes uniquely to superior Braille reading performance.