bluuebunny/crossref_metadata_2025 huggingface dataset:
Spatial Suppression and Sensitivity for Motion in Schizophrenia
Authors: Linares Daniel , Amoretti Silvia , Marin-Campos Rafael , Sousa André , Prades Laia , Dalmau Josep , Bernardo Miquel , Compte Albert
Published: September 2020

Perceptual spatial suppression is a phenomenon in which the perceived strength of a stimulus in some region of the space is reduced when the stimulus is surrounded by other stimuli. For contrast perception, several studies suggest that spatial suppression is reduced in patients with schizophrenia. For motion perception, only one study has been conducted in a cohort of 16 patients, suggesting that spatial suppression is reduced. It is unknown, however, whether this reduction is related to the lower intelligence quotient (IQ) that schizophrenic patients usually show; as there is evidence that spatial suppression for motion increases with IQ in healthy individuals. Here, we sought to determine the spatial suppression for motion in a larger cohort of 33 patients with schizophrenia, controlling for IQ. We found a weakened spatial suppression in patients with schizophrenia, consistent with the previous study (g = 0.47, CI = [0.055, 0.88], combining the previous and our study). For comparison, we performed a meta-analysis on spatial suppression for contrast and found a similar effect size. We found that patients had a lower IQ than controls, but this difference did not explain their weaker spatial suppression. Further, we found that spatial suppression of patients, but not controls, increased with their IQ and, it decreased with age in both groups. Finally, as we estimated lapses of attention, we could estimate motion sensitivity and found that it was decreased in patients. We speculate about possible alterations in neurotransmission that might explain the reduced spatial suppression and sensitivity that we found.
Medicine as a Lens to Examine Cross-Cultural Encounters: A Study of Medical Missionary Samuel Hayward Ford’s Writings in Nineteenth-Century New Zealand
Authors: Tilson Kate
Published: September 2020

Medical missionary Samuel Hayward Ford arrived in New Zealand’s Bay of Islands in the late 1830s, a few years before the formal colonisation of the country. His letters and medical reports to the Committee of the Church Missionary Society revealed the complicated and malleable nature of medicine in the cross-cultural encounter. Through close study of Ford’s writings, this article argues that medicine worked to transform and interweave Māori and missionary worlds in precolonial New Zealand. Experiencing the spread of disease in the Bay of Islands, Ford practised and was influenced by evangelical humanitarianism, and he was also entangled in the politics of empire. More than this, his medicine exposed the missionary objective to transform Māori society, and it showcased not just cultural differences regarding medical knowledge but also the exchange of ideas and treatments between Māori and the missionaries.
“Different Strolls, Different Worlds? Gentrification and its Impact on Outdoor Sex Work”
Authors: Oselin Sharon S , Hail-Jares Katie , Kushida Melanie
Published: September 2020

Research reveals mixed findings regarding gentrification’s effects on longtime residents and legal small businesses. There is only minimal examination of the ways in which urban redevelopment impacts illicit outdoor marketplaces, and the studies that do rarely employ a comparative analysis or focus on individual perceptions regarding such changes. Using the case of street-based sex work, this study illuminates how workers in the outdoor trade assess changing work conditions and establishes that such evaluations color workers’ decision-making. We draw on interviews with 51 sex workers of color who are familiar with two divergent sex work “strolls” in Washington, DC. Our findings suggest that participants perceive gentrification as a multifaceted phenomenon that reconfigures their work by altering social support, environmental conditions, and competition, changes which ultimately inform where they ply their trade. This research shows that individuals in illicit outdoor markets consider the ramifications of urban redevelopment on their work and make strategic decisions that have implications for their emotional, physical, and financial well-being.
An Evolving View of Phylogenetic Support
Authors: Simon Chris
Published: September 2020

If all nucleotide sites evolved at the same rate within molecules and throughout the history of lineages, if all nucleotides were in equal proportion, if any nucleotide or amino acid evolved to any other with equal probability, if all taxa could be sampled, if diversification happened at well-spaced intervals, and if all gene segments had the same history, then tree building would be easy. But of course, none of those conditions are true. Hence, the need for evaluating the information content and accuracy of phylogenetic trees. The symposium for which this historical essay and presentation were developed focused on the importance of phylogenetic support, specifically branch support for individual clades. Here, I present a timeline and review significant events in the history of systematics that set the stage for the development of the sophisticated measures of branch support and examinations of the information content of data highlighted in this symposium. [Bayes factors; bootstrap; branch support; concordance factors; internode certainty; posterior probabilities; spectral analysis; transfer bootstrap expectation.]
Steady-State Visual Evoked Potentials Elicited from Early Visual Cortex Reflect Both Perceptual Color Space and Cone-Opponent Mechanisms
Authors: Kaneko Sae , Kuriki Ichiro , Andersen Søren K
Published: September 2020

Colors are represented in the cone-opponent signals, L-M versus S cones, at least up to the level of inputs to the primary visual cortex. We explored the hue selective responses in early cortical visual areas through recordings of steady-state visual evoked potentials (SSVEPs), elicited by a flickering checkerboard whose color smoothly swept around the hue circle defined in a cone-opponent color space. If cone opponency dominates hue representation in the source of SSVEP signals, SSVEP amplitudes as a function of hue should form a profile that is line-symmetric along the cardinal axes of the cone-opponent color space. Observed SSVEP responses were clearly chromatic ones with increased SSVEP amplitudes and reduced response latencies for higher contrast conditions. The overall elliptic amplitude profile was significantly tilted away from the cardinal axes to have the highest amplitudes in the “lime-magenta” direction, indicating that the hue representation in question is not dominated by cone-opponency. The observed SSVEP amplitude hue profile was better described as a summation of a perceptual response and cone-opponent responses with a larger weight to the former. These results indicate that hue representations in the early visual cortex, measured by the SSVEP technique, are possibly related to perceptual color contrast.
Skipping a Beat: Heartbeat-Evoked Potentials Reflect Predictions during Interoceptive-Exteroceptive Integration
Authors: Banellis Leah , Cruse Damian
Published: September 2020

Several theories propose that emotions and self-awareness arise from the integration of internal and external signals and their respective precision-weighted expectations. Supporting these mechanisms, research indicates that the brain uses temporal cues from cardiac signals to predict auditory stimuli and that these predictions and their prediction errors can be observed in the scalp heartbeat-evoked potential (HEP). We investigated the effect of precision modulations on these cross-modal predictive mechanisms, via attention and interoceptive ability. We presented auditory sequences at short (perceived synchronous) or long (perceived asynchronous) cardio-audio delays, with half of the trials including an omission. Participants attended to the cardio-audio synchronicity of the tones (internal attention) or the auditory stimuli alone (external attention). Comparing HEPs during omissions allowed for the observation of pure predictive signals, without contaminating auditory input. We observed an early effect of cardio-audio delay, reflecting a difference in heartbeat-driven expectations. We also observed a larger positivity to the omissions of sounds perceived as synchronous than to the omissions of sounds perceived as asynchronous when attending internally only, consistent with the role of attentional precision for enhancing predictions. These results provide support for attentionally modulated cross-modal predictive coding and suggest a potential tool for investigating its role in emotion and self-awareness.
Gender Representation Matters: Intervention to Solicit Medical Resident Input to Enable Equity in Leadership in Graduate Medical Education
Authors: Klein Robin , Law Karen , Koch Jennifer
Published: September 2020

Problem

Gender equity in leadership across academic medicine remains a concern. The case of chief resident (CR) offers an opportunity to explore novel strategies in leadership selection in graduate medical education (GME). Means of identifying potential candidates for CR often rely on faculty assessment of resident performance, yet implicit gender bias has the potential to influence this assessment.

Approach

To diversify the metrics used in CR selection, an intervention was implemented to solicit resident input to identify candidates for CR at 2 U.S. internal medicine residency programs in 2018 and 2019. This involved a simple, cross-sectional survey of residents in which they were asked to identify individual residents as good candidates for consideration for CR.

Outcomes

There were 298 of 518 internal medicine resident responses to this intervention across sites and years (mean 58.2% response rate). Nomination patterns of residents and program leaders correlated significantly (correlation coefficient 0.62, P < .001). Controlling for site and year, gender was a significant factor associated with who residents nominated for CR (β-coefficient 0.325, P = .004) with women residents more likely to identify women for CR (odds ratio 1.38, 95% confidence interval 1.11–1.73). Fifty residents nominated themselves for CR, and there was no significant difference by gender (β-coefficient 0.038, P = .91).

Next Steps

Soliciting resident input to identify candidates for CR may enable gender representation of candidates for this position. Influencing candidate choices may be a promising way to impact leadership selection in medicine.
How Do OSCE Cases Activate Learners About Transgender Health?
Authors: Greene Richard E. , Blasdel Gaines , Cook Tiffany E. , Gillespie Colleen
Published: September 2020

Purpose

To describe the effect of transgender health–related objective structured clinical examination (THOSCE) case exposure on learner activation regarding gender-affirming care.

Method

A modified grounded theory approach was applied to identify the educational value of THOSCE cases. Focus groups with current and former primary care internal medicine residents who participated in THOSCE cases were conducted in 2018–2019. Transcripts were analyzed and coded until saturation to identify themes.

Results

Eighteen (72%) eligible learners participated in the focus groups. Themes were identified relating to gender-affirming care, and modified grounded theory analysis was used as a framework to organize the themes into 4 stages of learner activation: (1) believing the learner role is important, (2) having the confidence and knowledge necessary to take action, (3) taking action to maintain and improve one’s skills, and (4) staying the course even under stress.

Conclusions

Residents were grateful for the opportunity to practice the skills involved in transgender health in a simulation. Many felt unprepared and were concerned about how they were perceived by the standardized patient and faculty. Residents identified feeling more comfortable with gender-affirming language in the inpatient setting, which may provide an opportunity for learning in the future. Residents identified the psychosocial skills of gender-affirming care as more directly relevant while biomedical aspects of gender-affirming care seemed less accessible to residents, given the lack of outpatient experience. The authors propose a staged approach to teaching the skills of gender-affirming care using simulation to address learners of all levels.
Addressing and Undoing Racism and Bias in the Medical School Learning and Work Environment
Authors: Hess Leona , Palermo Ann-Gel , Muller David
Published: September 2020

Racism and bias are American medicine’s fatal flaw. They permeate clinical practice and biomedical research, and their influence on medical education is even more profound because it is through medical education that racism and bias are perpetuated across generations and throughout history. This insidious influence has persisted despite the stated values of the medical profession and well-intentioned efforts to lessen their impact. The authors assert that racism and bias in the learning and work environment of medical school can be mitigated only through a formal change management process that leads to change that is institutionally transformational and individually transformative. The authors describe the sequence of events at one U.S. medical school, beginning in 2016, that led from student activism to an initiative that encompasses every functional sphere within medical education. They also reflect on personal and structural lessons learned during the course of designing and implementing this initiative. Eliminating racism and bias demands that medical educators embrace a change process that is lifelong, people-centered, incremental, and nonlinear. It requires the courage to constantly course correct while never losing sight of the ultimate goal: health care and medical education that are free of racism and bias.
Using Rapid Design Thinking to Overcome COVID-19 Challenges in Medical Education
Authors: Thakur Anupam , Soklaridis Sophie , Crawford Allison , Mulsant Benoit , Sockalingam Sanjeev
Published: September 2020

The rapid rise of cases of coronavirus disease 2019 (COVID-19) has led to the implementation of public health measures on an unprecedented scale. These measures have significantly affected the training environment and the mental health of health care providers and learners. Design thinking offers creative and innovative solutions to emergent complex problems, including those related to training and patient care that have arisen as a result of the COVID-19 pandemic. Design thinking can accelerate the development and implementation of solution prototypes through a process of inspiration, ideation, and implementation. Digital technology can be leveraged as part of this process to provide care and education in new or enhanced ways. Online knowledge hubs, videoconference-based interactive sessions, virtual simulations, and technology-enhanced coaching for health care providers are potential solutions to address identified issues. Limitations of this model include inherent bias toward utilitarian instead of egalitarian principles and the subsequent threat to diversity, equity, and inclusion in solutions. Although medical educators have embraced digital transformation during the COVID-19 pandemic, there is a need to ensure that these changes are sustained.
SARS-CoV-2 found in semen
Authors: Carpinello Olivia J.
Published: September 2020

With a novel coronavirus comes novel unknowns. One such unknown was whether or not the SARS-CoV-2 virus could be detected in semen. A recent report demonstrated the presence of the virus in semen, which raises additional questions.
Magic state distillation with the ternary Golay code
Authors: Prakash Shiroman
Published: September 2020

The ternary Golay code—one of the first and most beautiful classical error-correcting codes discovered—naturally gives rise to an 11-qutrit quantum error correcting code. We apply this code to magic state distillation, a leading approach to fault-tolerant quantum computing. We find that the 11-qutrit Golay code can distil the ‘most magic’ qutrit state—an eigenstate of the qutrit Fourier transform known as the
strange state
—with cubic error suppression and a remarkably high threshold. It also distils the ‘second-most magic’ qutrit state, the Norell state, with quadratic error suppression and an equally high threshold to depolarizing noise.
Classifying financial markets up to isomorphism
Authors: Armstrong J.
Published: September 2020

Two markets should be considered isomorphic if they are financially indistinguishable. We define a notion of isomorphism for financial markets in both discrete and continuous time. We then seek to identify the distinct isomorphism classes, that is to classify markets. We classify complete one-period markets. We define an invariant of continuous-time complete markets which we call the absolute market price of risk. This invariant plays a role analogous to the curvature in Riemannian geometry. We classify markets when the absolute market price of risk is deterministic. We show that, in general, markets with non-trivial automorphism groups admit mutual fund theorems. We prove a number of such theorems.
The evolution of startle displays: a case study in praying mantises
Authors: Vidal-García Marta , O'Hanlon James C. , Svenson Gavin J. , Umbers Kate D. L.
Published: September 2020

Anti-predator defences are typically regarded as relatively static signals that conceal prey or advertise their unprofitability. However, startle displays are complex performances that deter or confuse predators and can include a spectacular array of movements, colours and sounds. Yet, we do not fully understand the mechanisms by which they function, their evolutionary correlates, or the conditions under which they are performed and evolve. Here, we present, to our knowledge, the first phylogenetically controlled comparative analyses of startle displays including behavioural data, using praying mantises as a model system. We included 58 species that provide a good representation of mantis diversity and estimated the strength of phylogenetic signal in the presence and complexity of displays. We also tested hypotheses on potential evolutionary correlates, including primary defences and body size. We found that startle displays and morphological traits were phylogenetically conserved, whereas behavioural traits were highly labile. Surprisingly, body size was not correlated with display presence or complexity in phylogenetically controlled analyses. Species-rich clades were more likely to exhibit displays, suggesting that startle displays were probably involved in lineage diversification. We suggest that to further elucidate the conditions under which startle displays evolve, future work should include quantitative descriptions of multiple display components, habitat type, and predator communities. Understanding the evolution of startle displays is critical to our overall understanding of the theory behind predator–prey dynamics.
Context-dependent modulation of natural approach behaviour in mice
Authors: Procacci Nicole M. , Allen Kelsey M. , Robb Gael E. , Ijekah Rebecca , Lynam Hudson , Hoy Jennifer L.
Published: September 2020

Specific features of visual objects innately draw approach responses in animals, and provide natural signals of potential reward. However, visual sampling behaviours and the detection of salient, rewarding stimuli are context and behavioural state-dependent and it remains unclear how visual perception and orienting responses change with specific expectations. To start to address this question, we employed a virtual stimulus orienting paradigm based on prey capture to quantify the conditional expression of visual stimulus-evoked innate approaches in freely moving mice. We found that specific combinations of stimulus features selectively evoked innate approach or freezing responses when stimuli were unexpected. We discovered that prey capture experience, and therefore the expectation of prey in the environment, selectively modified approach frequency, as well as altered those visual features that evoked approach. Thus, we found that mice exhibit robust and selective orienting responses to parameterized visual stimuli that can be robustly and specifically modified via natural experience. This work provides critical insight into how natural appetitive behaviours are driven by both specific features of visual motion and internal states that alter stimulus salience.
Microplastics negatively affect soil fauna but stimulate microbial activity: insights from a field-based microplastic addition experiment
Authors: Lin Dunmei , Yang Guangrong , Dou Pengpeng , Qian Shenhua , Zhao Liang , Yang Yongchuan , Fanin Nicolas
Published: September 2020

Microplastics are recognized as an emerging contaminant worldwide. Although microplastics have been shown to strongly affect organisms in aquatic environments, less is known about whether and how microplastics can affect different taxa within a soil community, and it is unclear whether these effects can cascade through soil food webs. By conducting a microplastic manipulation experiment, i.e. adding low-density polyethylene fragments in the field, we found that microplastic addition significantly affected the composition and abundance of microarthropod and nematode communities. Contrary to soil fauna, we found only small effects of microplastics on the biomass and structure of soil microbial communities. Nevertheless, structural equation modelling revealed that the effects of microplastics strongly cascade through the soil food webs, leading to the modification of microbial functioning with further potential consequences on soil carbon and nutrient cycling. Our results highlight that taking into account the effects of microplastics at different trophic levels is important to elucidate the mechanisms underlying the ecological impacts of microplastic pollution on soil functioning.
Adhaeribacter rhizoryzae sp. nov., a fibrillar matrix-producing bacterium isolated from the rhizosphere of rice plant
Authors: Chhetri Geeta , Kim Jiyoun , Kim Inhyup , Lee Byungjo , Jang Wonhee , Seo Taegun
Published: September 2020

A novel fibrillar matrix-producing, rod-shaped, red–orange, asporogenous, aerobic bacterium, designated DK36T, was isolated from roots of a rice plant in the Ilsan region near Dongguk University, South Korea. Cells of strain DK36T were Gram-stain-negative and motile by means of gliding. The temperature and pH ranges for growth were 7–35 °C (optimum: 30 °C) and pH 5–10 (optimum: pH 7.0). The strain did not require NaCl for growth but tolerated up to 8 % (w/v) NaCl. Phylogenetic anlaysis of the 16S rRNA gene sequence revealed that DK36T formed a monophyletic clade with

Adhaeribacter aerophilus

6425 S-25T,

Adhaeribacter aerolatus

6515 J-31T and

Adhaeribacter swui

17mud1-7T with sequence similarities of 96.3, 95.5 and 95.2%, respectively. The average nucleotide identity and in silico DNA–DNA hybridization values of strain DK36T with the most closely related strains whose whole genomes are publicly available were 72.5–83.6% and 19–28 %, respectively. The strain showed the typical chemotaxonomic characteristics of the genus

Adhaeribacter

, with the presence of menaquinone MK-7 as the respiratory quinone, and C16 : 1ω5c, iso-C15 : 0 and summed feature 4 (composed of iso-C17 : 1 I/anteiso-C17 : 1 B) as the major fatty acids. The polar lipid profile consisted of phosphatidylethanolamine, one unidentified aminophosphoglycolipid, one unidentified phospholipid, two unidentified aminolipids and five unidentified polar lipids. The genomic DNA G+C content based on the draft genome sequence was 43.4 mol%. The results of physiological and biochemical tests and 16S rRNA gene sequence analysis clearly revealed that strain DK36T represents a novel species of the genus

Adhaeribacter

, for which the name Adhaeribacter rhizoryzae sp. nov. is proposed. The type strain is DK36T (=KACC 19902T=NBRC 113689T).
The evolution of Covid-19 in Italy during the Summer 2020: analysis and interpretation of an unpredicted rest period
Authors: De Natale Giuseppe , De Natale Lorenzo , Troise Claudia , Somma Renato , Marchitelli Vito , Coviello Antonio , Holmberg Karen G.
Published: September 2020

The coronavirus (COVID-19) pandemic was particularly invasive in Italy during the period of March to the end of April 2020 then displayed a significant decrease both in the number of infections and in the seriousness of illness throughout the summer of 2020. In this discussion, we measure the seriousness of the disease by the ratio of Intensive Care Units (ICU) spaces occupied by COVID-19 patients and the number of still Active Cases (AC) each month from April to August 2020. We also use the ratio between the number of Deaths (D) and the number of Active Cases. What clearly emerges, from rigorous statistical analysis, is a progressive decrease of both the ratios, indicating progressive mitigation of the disease. This is particularly evident when comparing March-April with July-August; during the summer period the two ratios have become roughly 18 times lower. We test such sharp decreases against possible bias in counting active cases, and we confirm their statistical significance. We then interpret such evidence in terms of the well-known seasonality of the human immune system and the virus-inactivating effect of stronger UV rays in the summer.
Intra-Arterial Blood Pressure Measurement: Sources of Error and Solutions
Authors: Devasahayam Suresh , Surekha C. , Baskaran Bowya , Gangadharan Naveen , Mukadam Farhan Adam , Subramani Sathya
Published: September 2020

Rationale

Intra-arterial blood pressure measurement is the cornerstone of hemodynamic monitoring in Intensive Care Units (ICU). Accuracy of the measurement is dependent on the dynamic response of the measuring system, defined by its natural frequency (fnatural) and damping coefficient (Zdamping) which are estimated with a Fast-flush test. Locating the experimentally measured fnatural and Zdamping on the plot in the original paper by Gardner (1981) which defined the acceptable limits for these 2 parameters, has long been the only way to determine the accuracy of the pressure measurement.

In this paper, we extend the current understanding of the effect of poor dynamic response of the measurement system, enhance the usefulness of Gardner’s plots by providing a numerical value for the error in pressure measurement (for a given set of conditions) and depict the gradation of error value as heat maps, and also demonstrate the usefulness of a tunable filter for error correction.

Objectives

(i) Estimation of the amplitude of error in pressure measurement through simulations based on real-world data, and development of heat-maps for easy use by physicians to assess if the recording conditions are optimal (ii) A new method to correct the error.

Methods and Results

Simulated blood pressure waveforms of various heart rates and pressure levels were passed through simulated measurement systems with varying fnatural and Zdamping. The numerical errors in systolic and diastolic pressures and mean error in the measured pressure were used to generate heat maps denoting the errors for the various recording conditions, in the same plot as that by Gardner (1981). Performance of a tunable filter to correct the error is demonstrated.

Conclusions

In many clinical settings the measurement of intra-arterial pressure is prone to significant error. The proposed tunable filter is shown to improve the accuracy of intra-arterial pressure recording.
Entry screening and multi-layer mitigation of COVID-19 cases for a safe university reopening
Authors: Elbanna Ahmed , Wong George N. , Weiner Zach J. , Wang Tong , Zhang Hantao , Liu Zhiru , Tkachenko Alexei , Maslov Sergei , Goldenfeld Nigel
Published: September 2020

We have performed detailed modeling of the COVID-19 epidemic within the State of Illinois at the population level, and within the University of Illinois at Urbana-Champaign at a more detailed level of description that follows individual students as they go about their educational and social activities.

We ask the following questions:

How many COVID-19 cases are expected to be detected by entry screening?

Will this initial “bump” in cases be containable using the mitigation steps being undertaken at UIUC?

Our answers are:

Assuming that there are approximately 45,000 students returning to campus in the week beginning August 15, 2020, our most conservative estimate predicts that a median of 270 ± 90 (minimum-maximum range) COVID-19 positive cases will be detected by entry screening. The earliest estimate for entry screening that we report was made on July 24th and predicted 198 ± 90 (68% CI) positive cases.

If the number of returning students is less, then our estimate just needs to be scaled proportionately.

This initial bump will be contained by entry screening initiated isolation and contact tracing, and once the semester is underway, by universal masking, a hybrid teaching model, twice-weekly testing, isolation, contact tracing, quarantining and the use of the Safer Illinois exposure notification app.
Analyzing inherent biases in SARS-CoV-2 PCR and serological epidemiologic metrics
Authors: Makhoul Monia , Abou-Hijleh Farah , Seedat Shaheen , Mumtaz Ghina R , Chemaitelly Hiam , Ayoub Houssein , Abu-Raddad Laith J.
Published: September 2020

Background

Prospective observational data show that infected persons with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remain polymerase chain reaction (PCR) positive for a prolonged duration, and that detectable antibodies develop slowly with time. We aimed to analyze how these effects can bias key epidemiological metrics used to track and monitor SARS-CoV-2 epidemics.

Methods

An age-structured mathematical model was constructed to simulate progression of SARS-CoV-2 epidemics in populations. PCR testing to diagnose infection and cross-sectional surveys to measure seroprevalence were also simulated. Analyses were conducted on simulated outcomes assuming a natural epidemic time course and an epidemic in presence of interventions.

Results

The prolonged PCR positivity biased the epidemiological measures. There was a lag of 10 days between the true epidemic peak and the actually-observed peak. Prior to epidemic peak, PCR positivity rate was 2-fold higher than that based only on current active infection, and half of those tested positive by PCR were in the prolonged PCR positivity stage after infection clearance. Post epidemic peak, PCR positivity rate poorly predicted true trend in active infection. Meanwhile, the prolonged PCR positivity did not appreciably bias estimation of the basic reproduction number R0. The time delay in development of detectable antibodies biased measured seroprevalence. The actually-observed seroprevalence substantially underestimated true prevalence of ever infection, with the underestimation being most pronounced around epidemic peak.

Conclusions

Caution is warranted in interpreting PCR and serological testing data, and any drawn inferences need to factor the effects of the investigated biases for an accurate assessment of epidemic dynamics.
Impact of temperature on Covid 19 in India
Authors: Roy Manas Pratim
Published: September 2020

The role of temperature in Covid 19 pandemic has been subjected to frequent review. An effort was made to find out such relations from three districts in India. Data were analyzed for 14 weeks. It appears that temperature could impact the spread of the pandemic.
A Low-cost, Low-energy Wearable ECG System with Cloud-Based Arrhythmia Detection
Authors: Huda Nurul , Khan Sadia , Abid Ragib , Shuvo Samiul Based , Labib Mir Maheen , Hasan Taufiq
Published: September 2020

Continuously monitoring the Electrocardiogram (ECG) is an essential tool for Cardiovascular Disease (CVD) patients. In low-resource countries, the hospitals and health centers do not have adequate ECG systems, and this unavailability exacerbates the patients’ health condition. Lack of skilled physicians, limited availability of continuous ECG monitoring devices, and their high prices, all lead to a higher CVD burden in the developing countries. To address these challenges, we present a low-cost, low-power, and wireless ECG monitoring system with deep learning-based automatic arrhythmia detection. Flexible fabric-based design and the wearable nature of the device enhances the patient’s comfort while facilitating continuous monitoring. An AD8232 chip is used for the ECG Analog Front-End (AFE) with two 450 mi-Ah Li-ion batteries for powering the device. The acquired ECG signal can be transmitted to a smart-device over Bluetooth and subsequently sent to a cloud server for analysis. A 1-D Convolutional Neural Network (CNN) based deep learning model is developed that provides an accuracy of 94.03% in classifying abnormal cardiac rhythm on the MIT-BIH Arrhythmia Database.

Index Terms

Wearable ECG, deep learning, arrhythmia detection.
Selecting COVID-19 Convalescent Plasma for Neutralizing Antibody Potency Using a High-capacity SARS-CoV-2 Antibody Assay
Authors: Goodhue Meyer E , Simmons G , Grebe E , Gannett M , Franz S , Darst O , Di Germanio C , Stone M , Contestable P , Prichard A , Reik R , Vassallo R , Young P , Busch MP , Williamson P , Dumont LJ
Published: September 2020

BACKGROUND

Efficacy of COVID-19 convalescent plasma (CCP) to treat COVID-19 is hypothesized to be associated with the concentration of neutralizing antibodies (nAb) to SARS-CoV-2. High capacity serologic assays detecting binding antibodies (bAb) have been developed, nAb assays are not adaptable to high-throughput testing. We sought to determine the effectiveness of using surrogate bAb signal-to-cutoff ratios (S/CO) in predicting nAb titers using a pseudovirus reporter viral particle neutralization (RVPN) assay.

METHODS

CCP donor serum collected by 3 US blood collectors was tested with a bAb assay (Ortho Clinical Diagnostics VITROS Anti-SARS-CoV-2 Total, CoV2T) and a nAb RVPN assay. CoV2T prediction effectiveness at S/CO thresholds was evaluated for RVPN nAb NT50 titers using receiver operating characteristic analysis.

RESULTS

753 CCPs were tested with median CoV2T S/CO of 71.2 and median NT50 of 527.5. Proportions of CCP donors with NT50 over various target nAb titers were 86% ≥1:80, 76% ≥1:160, and 62%≥1:320. Increasing CoV2Ts reduced the sensitivity to predict NT50 titers, while specificity to identify those below thresholds increased. As the targeted NT50 increased, the positive predictive value fell with reciprocal increase in negative predictive value. S/CO thresholds were thus less able to predict target NT50 titers.

CONCLUSION

Selection of a clinically effective nAb titer will impact availability of CCP. Product release with CoV2T assay S/CO thresholds must balance the risk of releasing products below target nAb titers with the cost of false negatives. A two-step testing scheme may be optimal, with nAb testing on CoV2T samples with S/COs below thresholds.
Estimation of a state of Corona 19 epidemic in August 2020 by multistage logistic model: a case of EU, USA, and World
Authors: Batista Milan
Published: September 2020

The article provides an estimate of the size and duration of the Covid-19 epidemic in August 2020 for the European Union (EU), the United States (US), and the World using a multistage logistical epidemiological model.
Modeling an epidemic in an imaginary small town
Authors: Bell Graham
Published: September 2020

The course of an epidemic in an imaginary small town has been simulated with an agent-based model. The reproduction number R of the virus could be counted directly, and was roughly, but not precisely, exponentially distributed. The number of secondary infections was greater for an infection which was itself one of many secondary infections because of environmental heterogeneity, which created variance of R among sites and could drive the spread of infection, even when global R < 1. Different kinds of intervention were deployed to curtail the spread of infection. Measures applied to the general population, such as closing down sites and services or regulating individual behaviour, did not reduce the total number of individuals infected during the epidemic unless they were maintained until the virus became extinct. This was primarily because measures taken to reduce indirect transmission tended to increase direct transmission, and vice versa. Consequently, the overall effect of any combination of interventions was much less than the sum of their separate effects. On the other hand, the quarantine of infected or exposed individuals was effective in driving the virus to extinction and caused a permanent and substantial reduction in the number of cases.
Daily rewiring of a neural circuit generates a predictive model of environmental light
Authors: Song Bryan J. , Sharp Slater J. , Rogulja Dragana
Published: September 2020

Ongoing sensations are compared to internal, experience-based, reference models; mismatch between reality and expectation can signal opportunity or danger, and can shape behavior. The nature of internal reference models is largely unknown. We describe a model that enables moment-to-moment luminance evaluation in flies. Abrupt shifts to lighting conditions inconsistent with the subjective time-of-day trigger locomotion, whereas shifts to appropriate conditions induce quiescence. The time-of-day prediction is generated by a slowly shifting activity balance between opposing neuronal populations, LNvs and DN1as. The two populations undergo structural changes in axon length that accord with, and are required for, conveying time-of-day information. Each day, in each population, the circadian clock directs cellular remodeling such that the maximum axonal length in one population coincides with the minimum in the other; preventing remodeling prevents transitioning between opposing internal states. We propose that a dynamic predictive model resides in the shifting connectivities of the LNv- DN1a circuit.
Engineering high-yield biopolymer secretion creates an extracellular protein matrix for living materials
Authors: Charrier Marimikel , Orozco-Hidalgo Maria Teresa , Tjahjono Nicholas , Li Dong , Molinari Sara , Ryan Kathleen R. , Ashby Paul D. , Rad Behzad , Ajo-Franklin Caroline M.
Published: September 2020

The bacterial extracellular matrix forms autonomously, giving rise to complex material properties and multicellular behaviors. Synthetic matrix analogues can replicate these functions, but require exogenously added material or have limited programmability. Here we design a two-strain bacterial system that self-synthesizes and structures a synthetic extracellular matrix of proteins. We engineeredCaulobacter crescentusto secrete an extracellular matrix protein composed of elastin-like polypeptide (ELP) hydrogel fused to Supercharged SpyCatcher (SC(-)). This biopolymer was secreted at levels of 60 mg/L, an unprecedented level of biopolymer secretion by a gram-negative bacterium. The ELP domain was swapped with either a crosslinkable variant of ELP or resilin-like polypeptide, demonstrating this system is flexible. The SC(-)-ELP matrix protein bound specifically and covalently to the cell surface of aC. crescentusstrain that displays a high-density array of SpyTag peptides via its engineered Surface-layer. Our work develops protein design rules for Type I secretion inC. crescentus, and demonstrates the autonomous secretion and assembly of programmable extracellular protein matrices, offering a path forward towards the formation of cohesive engineered living materials.

IMPORTANCE

Engineered living materials (ELM) aim to mimic characteristics of natural occurring systems, bringing the benefits of self-healing, synthesis, autonomous assembly, and responsiveness to traditional materials. Previous research has shown the potential of replicating the bacterial extracellular matrix (ECM) to mimic biofilms. However, these efforts require energy intensive processing or have limited tunability. We propose a bacterially-synthesized system that manipulates the protein content of the ECM, allowing for programmable interactions and autonomous material formation. To achieve this, we engineered a two-strain system to secrete a synthetic extracellular protein matrix (sEPM). This work is a step towards understanding the necessary parameters to engineering living cells to autonomously construct ELMs.
Analysis of Biological Noise in an Organelle Size Control System
Authors: Bauer David , Ishikawa Hiroaki , Wemmer Kimberly A. , Kondev Jane , Marshall Wallace F.
Published: September 2020

Analysis of fluctuation in organelle size provides a new way to probe the mechanisms of organelle size control systems. By analyzing cell-to-cell variation and within-cell fluctuations of flagellar length inChlamydomonas, we show that the flagellar length control system exhibits both types of variation. Cell to cell variation is dominated by cell size, while within-cell variation results from dynamic fluctuations that are subject to a constraint, providing evidence for a homeostatic size control system. We analyzed a series of candidate genes affecting flagella and found that flagellar length variation is increased in mutations which increase the average flagellar length, an effect that we show is consistent with a theoretical model for flagellar length regulation based on length-dependent intraflagellar transport balanced by length-independent disassembly. Comparing the magnitude and time-scale of length fluctuations with simple models suggests that tubulin assembly is not directly coupled with IFT-mediated arrival and that observed fluctuations involve tubulin assembly and disassembly events involving large numbers of tubulin dimers. Cells with greater differences in their flagellar lengths show impaired swimming but improved gliding motility, raising the possibility that cells have evolved mechanisms to tune intrinsic noise in length. Taken together our results show that biological noise exists at the level of subcellular structures, with a corresponding effect on cell function, and can provide new insights into the mechanisms of organelle size control.
Integrative proteomic and phosphoproteomic analysis of granulosa cells during follicular atresia in porcine
Authors: Yang Feng , Liu Qiang , Chen Yanhong , Ye Huizhen , Wang Han , Zeng Shenming
Published: September 2020

Ovarian follicular atresia is a natural physiological process; however, the mechanism is not fully understood. In this study, quantitative proteomic and phosphoproteomic analyses of granulosa cells (GC) in healthy (H), slightly atretic (SA), and atretic follicles (A) of porcine were performed by TMT labeling, enrichment of phosphopeptides and LC-MS/MS analysis. In total, 6,201 proteins were quantified and 4,723 phosphorylation sites of 1,760 proteins were quantified. In total, 24 (11 up, 13 down) and 50 (29 up, 21 down) proteins with a fold change (FC) > 5 were identified in H/SA and H/A, respectively. In addition, there were 20 (H/SA, up) and 39 (H/A, up) phosphosites with an FC > 7, that could serve as potential biomarkers for distinguishing different quality categories of follicles. Western blotting and immunofluorescence confirmed the reliability of the proteomic analysis. Some key proteins (e.g., MIF, beta catenin, integrin β2), phosphosites (e.g., S76 of caspase6, S22 and S636 of lamin A/C), pathways (e.g., apoptosis, regulation of actin cytoskeleton pathway), transcription factors (e.g., STAT5A, FOXO1, and BCLAF1), and kinases (e.g., PBK, CDK5, CDK12, AKT3) involved in atresia process were revealed via further analysis of the differentially expressed proteins (DEPs) and phosphorylated proteins (DEPPs). Collectively, the proteomic and phosphoproteomic profiling and functional research in the current study comprehensively analyzed the dynamic changes in protein expression and phosphorylation during follicular atresia and provided some new explanations regarding the regulation of this process.
Prophylactic Application of Tailocins Prevents Infection byPseudomonas syringae
Authors: Baltrus David A. , Clark Meara , Hockett Kevin L. , Mollico Madison , Smith Caitlin , Weaver Savannah
Published: September 2020

Tailocins are phage-derived bacteriocins that demonstrate great potential as agricultural antimicrobials given their high killing efficiency and their precise strain-specific targeting ability. Our group has recently categorized and characterized tailocins produced by and tailocin sensitivities of the phytopathogenPseudomonas syringae, and here we extend these experiments to test whether prophylactic tailocin application can prevent infection ofNicotiana benthamianabyP. syringae pv. syringaeB728a. Specifically, we demonstrate that multiple strains can produce tailocins that prevent infection by strain B728a and engineer a deletion mutant to prove that tailocin targeting is responsible for this protective effect. Lastly, we provide evidence that heritable resistance mutations do not explain the minority of cases where tailocins fail to prevent infection. Our results extend previous reports of prophylactic use of tailocins against phytopathogens, and establish a model system with which to test and optimize tailocin application for prophylactic treatment to prevent phytopathogen infection.
Impact of COVID-19 pandemic on cancer care delivery : A Real World Experience
Authors: Pandey A , Mala R , Neelam C , Mridula P , Ravindra S , Kanchan M , Umesh Y , Shivkant S
Published: September 2020

Background

There is lack of information on impact of Corona Virus Disease (COVID-19) pandemic on routine cancer care delivery.

Aims and Objectives

To evaluate the change in Day Care Chemotherapy (DCC) and Out Patient Department (OPD) patient numbers before and after COVID-19 national lockdown.

Material and Methods

Demographic data, diagnosis, type and frequency of chemotherapy delivered in Day Care between 1st February 2020 to 31st July 2020 were retrieved. Out Patient Department daily patient numbers were collected. Descriptive statistics, Odds ratio, Chi-square and Student T test were used to measure change in pattern of DDC and OPD patient numbers before and after 24th March 2020 (day of Lockdown). Pearson correlation coefficient was used to measure the strength of correlation between rise in COVID-19 cases and patient numbers.

Results

3192 DCC and 8209 OPD visits were recorded in 126 working days. Median age was 47 years(SD + 19.06). Breast (17%) and Gall bladder(15%) were the most common cancers receiving chemotherapy. There was a significant decrease in number of DCC delivered in post COVID lockdown [mean 21.97 (+ 9.7)] compared to pre COVID lockdown [mean 33.30 (+11.4)], t=4.11, p = 0.001.There was a significant decrease in number of OPD visits in post COVID lockdown [mean 47.13 (+ 18.8)] compared to pre COVID lockdown [mean 89.91 (+30.0)], t=7.09, p = 0.001. The odds of receiving weekly chemotherapy over non weekly regimes significantly decreased post COVID lockdown with Odds ratio of 0.52 (95% CI, 0.36-0.75) with Chi square of 12.57, p =0.001. Daily COVID cases in State and OPD patient number were found to be moderately positively correlated on Pearson correlation coefficient, r = 0.35,p =0.001.

Conclusion

There was a significant fall in patient visit and chemotherapy cycles immediately after lockdown. The numbers increased later despite rise in COVID-19 cases.