bluuebunny/crossref_metadata_2025 huggingface dataset:
Early Hearing Preservation Outcomes Following Cochlear Implantation With New Slim Lateral Wall Electrode Using Electrocochleography
Authors: Walia Amit , Shew Matthew A. , Ettyreddy Abhinav , Lefler Shannon M. , Jiramongkolchai Pawina , Wick Cameron C. , Durakovic Nedim , Buchman Craig A. , Herzog Jacques A.
Published: February 2022

Objective:

Describe early hearing preservation (HP) cochlear implantation (CI) outcomes using a new slim lateral wall electrode (SLWE).

Study Design:

Prospective cohort study.

Setting:

Tertiary referral center.

Patients:

Adult CI candidates with preoperative low-frequency pure-tone average (LFPTA; 125, 250, 500 Hz) ≤60 dB HL.

Intervention:

CI with and without intracochlear real-time electrocochleography (RT-ECochG).

Main Outcome Measure:

HP (LFPTA ≤80 dB HL), LFPTA shift, speech-perception performance measures, postoperative CT reconstruction.

Results:

Forty-two subjects were implanted with the SLWE. Thirty patients underwent full insertion without RT-ECochG feedback, and HP was maintained at 3-months postactivation for 7 (23.3%) patients with mean LFPTA shift of 57.5 ± 25.6 dB HL. RT-ECochG feedback was utilized on 12 patients, of whom 6 patients had full insertions and 6 patients had anywhere from 1 to 3 electrodes left outside of the cochlea based on RT-ECochG feedback. At 3 months postoperatively, HP was achieved on 10 (83.3%) patients and mean LFPTA shift was 18.9 c 11.7 dB HL. Mean difference between LFPTA threshold shift at 3-months postactivation with and without RT-ECochG was 38.6 dB HL (95% CI, 25.6–51.67). There was an improvement in delta CNC from preoperative to 3-months postactivation when using RT-ECochG, with mean difference 20.7% (95% CI, 3.3–38.1).

Conclusions:

Use of RT-ECochG monitoring during SLWE placement results in fewer full electrode insertions and significantly better HP rates and speech-perception outcomes when compared with unmonitored insertions. Further investigation is needed to evaluate long-term audiologic outcomes to better understand the relationships among ECochG, cochlear trauma, functional outcomes, and HP.
Modified Power Piston Versus Simultaneous Stapedotomy With Hearing Aids in Otosclerosis: A Follow-Up Study Exploring Speech Recognition, Quality of Life and Usage of Device
Authors: Dejaco Daniel , Riedl David , Cassar Anna Elisabeth , Gottfried Timo , Rasse Thomas , Fischer Natalie , Kreuzer-Simonyan Armina , Seebacher Josef , Riechelmann Herbert , Keintzel Thomas , Schmutzhard Joachim
Published: February 2022

Objective:

To compare audiologic outcomes, quality-of-life (QoL) and usage-of-device (UoD) between case-matched, otosclerotic patients with mixed hearing loss (MHL) which received (a) stapedotomy and postoperative amplification with hearing aids (SDT+HA) or (b) short-incudial process coupled active middle ear implant with simultaneous stapedotomy (mPP).

Study design, setting, and patients:

Prospective, matched case-control, follow-up study conducted at two tertiary otologic referral centers. Eligible were all otosclerotic patients with MHL, which received mPP at either of the two institutions. A case-matched-cohort of SDT+HA-patients was generated from the hospitals database based on preoperative audiologic findings.

Main outcome measures:

For sound- and speech perception, primary outcome parameters were the mean postoperative, aided air-conduction pure tone average (mpa-AC-PTA) and word recognition score at 80 dB speech level (mpa-WRS), for QoL the mean Nijmegen-Cochlear-Implant-Questionnaire (NCIQ) total-score, and for UoD the mean score rated on a 10-point Likert-scale.

Results:

A total of 28 patients were included; 14 received mPP; mpa-AC-PTA and mpa-WRS significantly improved from 47.1 dB-HL to 34.3 dB-HL (−12.8 dB-HL; p < 0.001) and from 75.0% to 93.2% (+18.2%; p = 0.002) compared to 46.5 dB-HL to 31.9 dB-HL (−14.8 dB-HL; p < 0.008) and 75.0% to 93.2% (+18.2%; p = 0.002) for SDT+HA. No significant difference between groups was observed (all p > 0.1). NCIQ total-score between groups did not significantly differ (70.4 vs. 69.9; p = 0.93). UoD for mPP was significantly higher (6.1 vs. 3.0; p < 0.001).

Conclusions:

If medical/technical problems prevent usage of HA in otosclerosis with MHL, mPP can be considered as effective treatment option with similar audiological outcome and QoL. A significantly higher UoD for mPP was observed.
Nursing Infection Control Practice Adherence, Related Barriers, and Methods of Intervention
Authors: Driscoll Brendan , Evans Darlene
Published: February 2022

OBJECTIVE

This study aims to evaluate the level of infection control (IC) practice adherence and related barriers among nursing staff at a US academic medical center. Furthermore, it surveys staff to identify interventions to improve adherence with IC practices.

BACKGROUND

Infectious disease emergencies have exposed healthcare workers to increased infection risk. This study aims to explore IC practice adherence in the tertiary hospital setting and further investigate the personal protective equipment (PPE) champion role as a method to boost adherence.

METHODS

This descriptive quality improvement study includes 2 parts: 1) A PPE champion role was piloted to support healthcare worker adherence to IC practices; and 2) a survey was disseminated to nursing staff to identify the perceptions of their own and coworkers' adherence to IC practices as well as suggestions for improvement.

RESULTS

Twenty-six percent of PPE champion observations found nursing staff nonadherent with IC practices and policies. Barriers included knowledge deficit (38%), lack of motivation (38%), time constraints (21%), and lack of supplies (3%). Two hundred sixty-four RNs and nurse technicians responded to the IC survey. Nursing staff rated their IC adherence higher than observed by their peers. Perceived barriers to adherence included the lack of supplies (53%), knowledge of proper technique (41%), time constraints (35%), and motivation (5%). Staff recommended using PPE champions (52%) and mandating supervised practice of essential skills (48%) to increase adherence.

CONCLUSIONS

Nursing staff reported barriers related to their knowledge of proper technique and suggested interventions including supervised practice of critical skills. It seems that the PPE champion role is a popular method to boost IC practice adherence that can be implemented during pandemic and nonpandemic environments at minimal cost.
Crisis Leadership During and After the COVID Pandemic
Authors: Turnipseed David L. , VandeWaa Elizabeth A.
Published: February 2022

This article explores crisis leadership, with the purpose of offering a series of leadership behaviors and strategies for nurse administrators to limit and reduce the harm of crises, specifically the COVID-19 pandemic, to healthcare professionals. Based on the assumption that generic or universal crisis management approaches are generally ineffective and efficacious crisis management must be tailored to a specific crisis, a study was conducted to identify the most serious COVID-based stressors. The results revealed 5 categories of COVID stressors which are, in ascending order: miscellaneous, administration, patients/patient family issues, inherent aspect of the job (nursing), and personal issues. Personal issues comprised more than half of the greatest COVID-specific stressors. Building on relevant crisis management literature and the identification of COVID-specific stressors, this article provides suggestions and proven tactics for nurse administrators to guide their crisis leadership efforts for the COVID-19 pandemic. The lessons of this article are applicable to other crises.
Competency Status and Desire for Training in Core Public Health Domains: An Analysis by Job Level
Authors: Cunningham James K.
Published: February 2022

Context:

Although trainings on core public health domains are widely available, and experts concur that competency in multiple core domains (analysis/assessment, leadership, communication, etc) is desirable for public health professionals, many still lack such competency. Employee job level could be a factor, as organizational research indicates that broad skill sets often hold importance mainly for higher-level employees.

Objective:

This study examines whether the association between competency and desire for training in core public health domains depends on job level.

Design:

A training preferences and domain competency survey of public health professionals: nonmanagers (n = 790), middle managers (n = 332), and upper managers (n = 69). The association of competency in domains overall with number of related training topics desired was examined using median tests. The association of competency in individual domains with desire for specific related training topics was assessed using logistic regressions adjusted for education.

Settings:

Public health departments in the US Southwest (2013-2019).

Main Outcome Measures:

Competence in core domains: Financial Planning and Management, Analysis/Assessment, Communication, Cultural Competency, Leadership/Systems Thinking, Policy Development/Program Planning, Public Health Sciences, and Community Dimensions of Practice. Desire for training (yes/no) in 25 domain-related topics.

Results:

Upper managers lacking overall competence in core domains desired more training topics than their competent counterparts (median of 12 topics vs 5, P = .02). In contrast, nonmanagers lacking overall competence desired fewer topics than their competent counterparts (4 vs 6, P < .001). Upper managers with lesser competency in an individual domain often had significantly higher odds of desiring training related to the domain, but the opposite was found for nonmanagers. Among middle managers, little association between competency and training desire was found.

Conclusions:

Ideally, lesser competence in core domains would be accompanied by greater desire for ameliorative training, but only upper managers exhibited this pattern. Efforts are needed to better connect domain competency status and training desire among nonmanagers and middle managers.
The Association of COVID-19 Infection and Vaccination Rates in Florida
Authors: Bernet Patrick
Published: February 2022

Objective:

This study investigates the association of COVID-19 infection and vaccination rates with 2020 presidential election voting preference in Florida counties and the moderating role of age, race, ethnicity, and other community characteristics.

Methods:

Florida county COVID-19 infection and vaccination counts through September 2021 were supplemented with socioeconomic characteristics and 2020 presidential election results. Poisson regression measured the association of infection and vaccination rates with county political preferences, race, ethnicity, and other county demographic and economic characteristics. For models of April through September 2021 infection rates, the same county characteristics were assessed alongside county vaccination levels.

Results:

Each 1% increase in county full vaccination rates was associated with 82.47 fewer infections per 100 000 during the span of April to September 2021. Vaccination rate was the largest and most statistically significant determinant of vaccine era infections. Each 1% increase in the county share of votes for the 2020 Republican presidential candidate was associated with 109.7 more COVID-19 infections per 100 000 through March 2021 and a 0.546% decrease in county vaccination rates through September 2021.

Conclusions:

At the county level, COVID-19 vaccination rates are associated with infection rates, with a higher county population proportion of fully vaccinated associated with fewer infections per 100 000. County political preference in the 2020 presidential election is significantly associated with county-level COVID-19 infection and vaccination rates.
Effect of Adjuvant Steroid Therapy in Type 3 Biliary Atresia
Authors: Lu Xuexin , Jiang Jingying , Shen Zhen , Chen Gong , NP Ying Wu , Xiao Xianmin , Yan Weili , Zheng Shan
Published: February 2022

Objective:

To evaluate the efficacy and side effects of additional postoperative steroid therapy for type 3 BA versus the current routine care.

Summary Background Data:

Whether steroid therapy post-Kasai portoen-terostomy improves the outcomes of BA remains controversial. Clinical evidence from 2 randomized trials in the UK and USA do not support the routine use of steroid in the treatment of BA.

Methods:

In this open-label randomized controlled trial, patients with type 3 BA were randomized to routine postoperative treatment with or without 10 to 12 weeks of adjuvant steroid treatment. The primary outcome was the postoperative jaundice clearance rate with native liver at 6 months. The secondary outcomes included postoperative jaundice clearance rate at 3, 12, and 24 months, survival with native liver at 12 and 24 months, and SAEs within 3 months.

Results:

Overall, 200 participants were randomized and allocated into either steroid or control group (n = 100/group). The proportion of participants that are jaundice free without liver transplantation was significantly higher in the steroid group than in the control group at 6 months (54.1% vs 31.0%, P = 0.0015). The native liver survival rate was higher postoperatively in the steroid group than in the control group at 12 (66.3% vs 50.0%, P = 0.02) and 24 (57.1% vs 40.0%, P = 0.02) months. The survival time with native liver was significantly longer in the steroid group than in the control group (median survival, steroid vs control: not reached vs 1.21 years, P = 0.02). There were no significant differences between the 2 groups in the mean occurrence of SAEs within 3 months (steroid vs control: 0.63 vs 0.45, P = 0.20).

Conclusions:

Postoperative adjuvant steroid intervention improved bile drainage and survival with native liver in type 3 BA patients, without increasing early-stage SAEs.
Comment on ‘Quantum correlations are weaved by the spinors of the Euclidean primitives’
Authors: Gill R. D.
Published: February 2022

I point out fundamental mathematical errors in the recent paper published in this journal ‘Quantum correlations are weaved by the spinors of the Euclidean primitives’ by Joy Christian.
Intra-individual behavioural and neural signatures of audience effects and interactions in a mirror-game paradigm
Authors: Zimmermann Marius , Lomoriello Arianna Schiano , Konvalinka Ivana
Published: February 2022

We often perform actions while observed by others, yet the behavioural and neural signatures of audience effects remain understudied. Performing actions while being observed has been shown to result in more emphasized movements in musicians and dancers, as well as during communicative actions. Here, we investigate the behavioural and neural mechanisms of observed actions in relation to individual actions in isolation and interactive joint actions. Movement kinematics and EEG were recorded in 42 participants (21 pairs) during a mirror-game paradigm, while participants produced improvised movements alone, while observed by a partner, or by synchronizing movements with the partner. Participants produced largest movements when being observed, and observed actors and dyads in interaction produced slower and less variable movements in contrast with acting alone. On a neural level, we observed increased mu suppression during interaction, as well as to a lesser extent during observed actions, relative to individual actions. Moreover, we observed increased widespread functional brain connectivity during observed actions relative to both individual and interactive actions, suggesting increased intra-individual monitoring and action-perception integration as a result of audience effects. These results suggest that observed actors take observers into account in their action plans by increasing self-monitoring; on a behavioural level, observed actions are similar to emergent interactive actions, characterized by slower and more predictable movements.
Machine learning methods trained on simple models can predict critical transitions in complex natural systems
Authors: Deb Smita , Sidheekh Sahil , Clements Christopher F. , Krishnan Narayanan C. , Dutta Partha S.
Published: February 2022

Forecasting sudden changes in complex systems is a critical but challenging task, with previously developed methods varying widely in their reliability. Here we develop a novel detection method, using simple theoretical models to train a deep neural network to detect critical transitions—the Early Warning Signal Network (EWSNet). We then demonstrate that this network, trained on simulated data, can reliably predict observed real-world transitions in systems ranging from rapid climatic change to the collapse of ecological populations. Importantly, our model appears to capture latent properties in time series missed by previous warning signals approaches, allowing us to not only detect if a transition is approaching, but critically whether the collapse will be catastrophic or non-catastrophic. These novel properties mean EWSNet has the potential to serve as an indicator of transitions across a broad spectrum of complex systems, without requiring information on the structure of the system being monitored. Our work highlights the practicality of deep learning for addressing further questions pertaining to ecosystem collapse and has much broader management implications.
Age, breed, sex and diet influence serum metabolite profiles of 2000 pet dogs
Authors: Puurunen Jenni , Ottka Claudia , Salonen Milla , Niskanen Julia E. , Lohi Hannes
Published: February 2022

As an individual's metabolism reflects health and disease states well, metabolomics holds a vast potential in biomedical applications. However, normal physiological factors, such as age, can also influence metabolism, challenging the establishment of disease-specific metabolic aberrations. Here, we examined how physiological and diet-related factors drive variance in the metabolism of healthy pet dogs. We analysed 2068 serum samples using a canine nuclear magnetic resonance (NMR) spectroscopy-based metabolomics platform. With generalized linear models, we discovered that age, breed, sex, sterilization, diet type and fasting time significantly affected the canine metabolite profiles. Especially, breed and age caused considerable variation in the metabolite concentrations, and breeds with very different body conformations systematically differed in several lipid measurands. Our results enhance the understanding how normal physiological factors influence canine metabolism, aid accurate interpretation of the NMR results, and suggest the NMR platform might be applied in identifying aberrations in nutrient absorption and metabolism.
Food security and emerging infectious disease: risk assessment and risk management
Authors: Trivellone Valeria , Hoberg Eric P. , Boeger Walter A. , Brooks Daniel R.
Published: February 2022

Climate change, emerging infectious diseases (EIDs) and food security create a dangerous nexus. Habitat interfaces, assumed to be efficient buffers, are being disrupted by human activities which in turn accelerate the movement of pathogens. EIDs threaten directly and indirectly availability and access to nutritious food, affecting global security and human health. In the next 70 years, food-secure and food-insecure countries will face EIDs driving increasingly unsustainable costs of production, predicted to exceed national and global gross domestic products. Our modern challenge is to transform this business as usual and embrace an alternative vision of the biosphere formalized in the Stockholm paradigm (SP). First, a pathogen-centric focus shifts our vision of
risk space
, determining how pathogens circulate in realized and potential fitness space.
Risk space
and pathogen exchange are always heightened at habitat interfaces. Second, apply the document-assess-monitor-act (DAMA) protocol developing strategic data for EID risk, to be translated, synthesized and broadcast as actionable information.
Risk management
is realized through targeted interventions focused around information exchanged among a community of scientists, policy practitioners of food and public health security and local populations. Ultimately, SP and DAMA protect human rights, supporting food security, access to nutritious food, health interventions and environmental integrity.
Precipitation during two weeks in spring influences reproductive success of first-year females in the long-lived Natterer's bat
Authors: Stapelfeldt Bianca , Scheuerlein Alexander , Tress Christoph , Koch Ralf , Tress Johannes , Kerth Gerald
Published: February 2022

Bats are characterized by low reproductive rates in contrast with most of other small mammals. This makes their populations vulnerable when inclement environmental conditions such as cold and rainy weather impair the reproductive success of females. The fine-scale effect of weather on bats, however, remains largely unknown. Using a sliding window analysis approach on an 18-year individualized dataset on six Natterer's bat (
Myotis nattereri
) colonies, we investigated the effect of fine-scale weather conditions on age-specific reproductive success. We found that increased precipitation during a short time window in spring strongly reduced the probability of successful reproduction of first-year (FY) females. Our data suggest that this time window is concomitant with implantation or early pregnancy, before substantial investment into embryo development. In addition, larger FY had higher reproductive success, suggesting that reproduction may be condition dependent in young females. Reproductive success of older females was not affected by either weather or individual parameters. Our results show that changes in precipitation pattern may compromise the reproductive success of FY females. Further studies are needed to better understand the impact of weather conditions on reproductive success in long-lived bats under climate change scenarios.
Quantum measurement and colour perception: theory and applications
Authors: Berthier Michel , Provenzi Edoardo
Published: February 2022

In this paper, we make a systematic use of the quantum measurement theory to describe perceived colours and analyse some of their fundamental properties. After motivating the naturalness of the quantum measurement approach in the mathematical framework of the colour perception theory proposed by the authors in previous papers, we show how to obtain several results. Among our theoretical outcomes, we mention the possibility to confine the colour cone to a finite-volume colour solid and the link between post-measurement state changes, Lorentz boosts and the Einstein–Poincaré relativistic addition law. We apply these results to obtain a chromatic match equation that emphasizes the importance of the Hilbert–Klein metric on the unit disk and we also present a quantitative description of Hunt’s effect.
Aberration-corrected transmission electron microscopy of a non-graphitizing carbon
Authors: Allen Christopher S. , Ghamouss Fouad , Boujibar Ouassim , Harris Peter J. F.
Published: February 2022

Non-graphitizing carbons (NGCs) are an important class of solid carbons which cannot be converted into graphite by high-temperature heat treatment. They include commercially valuable materials such as activated carbon and glassy carbon. These carbons have been intensively studied for decades, but there is still no agreement about their detailed atomic structure, or the reasons for their resistance to graphitization. The first models for graphitizing and NGCs were proposed by Rosalind Franklin in the early 1950s, and while these are broadly correct, they are incomplete. Many alternative models of NGCs have been put forward since Franklin's time, but none has received universal acceptance. Diffraction and spectroscopic techniques can provide important insights into the nature of these carbons, but only direct microscopic imaging can reveal their true atomic structure. Here, we apply aberration-corrected transmission electron microscopy to an activated carbon prepared from waste biomass and present evidence for the presence of pentagonal and heptagonal carbon rings. This provides support for a model of the structure of NGC made up of curved fragments in which non-hexagonal rings are dispersed randomly throughout hexagonal networks.
Inconsistent evolution and growth–survival tradeoffs in
Gambusia affinis
Authors: Wood Zachary T. , Palkovacs Eric P. , Kinnison Michael T.
Published: February 2022

Growth–survival tradeoffs may be a generalizable mechanism influencing trajectories of prey evolution. Here, we investigate evolutionary contributions to growth and survival in western mosquitofish (
Gambusia affinis
) from 10 populations from high- and low-predation ancestral environments. We assess (i) the degree to which evolutionary components of growth and survival are consistent or inconsistent across populations within ancestral predation environments, and (ii) whether growth and survival trade off at the population level. We measure growth and survival on groups of common-reared mosquitofish in pond mesocosms. We find that evolution of growth is consistent, with fish from low-predation ancestral environments showing higher growth, while the evolution of survival is inconsistent, with significant population-level divergence unrelated to ancestral predation environment. Such inconsistency prevents a growth–survival tradeoff across populations. Thus, the generalizability of contemporary evolution probably depends on local context of evolutionary tradeoffs, and a continued focus on singular selective agents (e.g. predators) without such local context will impede insights into generalizable evolutionary patterns.
Sensitive periods, but not critical periods, evolve in a fluctuating environment: a model of incremental development
Authors: Walasek Nicole , Frankenhuis Willem E. , Panchanathan Karthik
Published: February 2022

Sensitive periods, during which the impact of experience on phenotype is larger than in other periods, exist in all classes of organisms, yet little is known about their evolution. Recent mathematical modelling has explored the conditions in which natural selection favours sensitive periods. These models have assumed that the environment is stable across ontogeny or that organisms can develop phenotypes instantaneously at any age. Neither assumption generally holds. Here, we present a model in which organisms gradually tailor their phenotypes to an environment that fluctuates across ontogeny, while receiving cost-free, imperfect cues to the current environmental state. We vary the rate of environmental change, the reliability of cues and the duration of adulthood relative to ontogeny. We use stochastic dynamic programming to compute optimal policies. From these policies, we simulate levels of plasticity across ontogeny and obtain mature phenotypes. Our results show that sensitive periods can occur at the onset, midway through and even towards the end of ontogeny. In contrast with models assuming stable environments, organisms always retain residual plasticity late in ontogeny. We conclude that critical periods, after which plasticity is zero, are unlikely to be favoured in environments that fluctuate across ontogeny.
Comparative genome analyses of five Vibrio penaeicida strains provide insights into their virulence-related factors
Authors: Ragab Wafaa , Kawato Satoshi , Nozaki Reiko , Kondo Hidehiro , Hirono Ikuo
Published: February 2022

Vibrio penaeicida

(family

Vibrionaceae

) is an important bacterial pathogen that affects Japanese shrimp aquaculture. Only two whole-genome sequences of

V. penaeicida

are publicly available, which has hampered our understanding of the pathogenesis of shrimp vibriosis caused by this bacterium. To gain insight into the genetic features, evolution and pathogenicity of V. penaeicida, we sequenced five

V. penaeicida

strains (IFO 15640T, IFO 15641, IFO 15642, TUMSAT-OK1 and TUMSAT-OK2) and performed comparative genomic analyses. Virulence factors and mobile genetic elements were detected. Furthermore, average nucleotide identities (ANIs), clusters of orthologous groups and phylogenetic relationships were evaluated. The

V. penaeicida

genome consists of two circular chromosomes. Chromosome I sizes ranged from 4.1 to 4.3 Mb, the GC content ranged from 43.9 to 44.1 %, and the number of predicted protein-coding sequences (CDSs) ranged from 3620 to 3782. Chromosome II sizes ranged from 2.2 to 2.4 Mb, the GC content ranged from 43.5 to 43.8 %, and the number of predicted CDSs ranged from 1992 to 2273. All strains except IFO 15641 harboured one plasmid, having sizes that ranged from 150 to 285 kb. All five genomes had typical virulence factors, including adherence, anti-phagocytosis, flagella-related proteins and toxins (repeats-in-toxin and thermolabile haemolysin). The genomes also contained factors responsible for iron uptake and the type II, IV and VI secretion systems. The genome of strain TUMSAT-OK2 tended to encode more prophage regions than the other strains, whereas the genome of strain IFO 15640T had the highest number of regions encoding genomic islands. For comparative genome analysis, we used

V. penaeicida

(strain CAIM 285T) as a reference strain. ANIs between strain CAIM 285T and the five

V. penaeicida

strains were >95 %, which indicated that these strains belong to the same species. Orthology cluster analysis showed that strains TUMSAT-OK1 and TUMSAT-OK2 had the greatest number of shared gene clusters, followed by strains CAIM 285T and IFO 15640T. These strains were also the most closely related to each other in a phylogenetic analysis. This study presents the first comparative genome analysis of

V. penaeicida

and these results will be useful for understanding the pathogenesis of this bacterium.
A deep learning model trained on only eight whole-slide images accurately segments tumors: wise data use versus big data
Authors: Perennec T. , Bourgade R. , Henno Sébastien , Sagan Christine , Toquet Claire , Rioux-Leclercq N. , Kammerer-Jacquet Solène-Florence , Loussouarn D. , Griebel M.
Published: February 2022

Computer-assisted pathology is one of the biggest challenges in the medicine of the future. However, artificial intelligence is struggling to gain acceptance in the broader medical community due to data security issues, lack of trust in the machine, and poor data availability. Here, we develop a tumor delineation algorithm with only eight whole slide images of ovarian cancer to demonstrate the feasibility of an artificial intelligence application created from only a few data, finely annotated and with optimal processing. We test the model on seventeen other slides from the same hospital. The predictions are similar to the ground truth annotations made by an expert pathologist, with a mean DICE score of 0.90 [0.85 - 0.93]. The results on slides from another hospital are consistent, suggesting that the model is generalizable and that its performance does not suffer from different data acquisition. This study demonstrates the feasibility of a contouring algorithm based on a reduced dataset well optimized, going against the commonly accepted idea that a phenomenal amount of data is paramount. This study paves the way for other medical applications, especially for rare pathologies with limited available data.
Non-invasive stimulation with Temporal Interference: Optimization of the electric field deep in the brain with the use of a genetic algorithm
Authors: Stoupis D. , Samaras T.
Published: February 2022

Objective

Since the introduction of transcranial temporal interference stimulation (tTIS), there has been an ever-growing interest in this novel method, as it theoretically allows non-invasive stimulation of deep brain target regions. To date, attempts have been made to optimize the electrode montages and injected current to achieve personalized area targeting using two electrode pairs. Most of these methods use exhaustive search to find the best match, but faster and, at the same time, reliable solutions are required. In this study, the aforementioned stimulation settings were optimized using a genetic algorithm.

Methods

Simulations were performed on head models from the Population Head Model (PHM) repository. First, each model was fitted with an electrode array based on the 10-10 international EEG electrode placement system. Following electrode placement, the models were meshed and solved for all single-pair electrode combinations using an electrode on the left mastoid as a reference (ground). At the optimization stage, different electrode pairs and injection currents were tested using a genetic algorithm to obtain the optimal combination for each model.

Results

Greater focality was achieved with optimization, specifically for the right hippocampus (region of interest), with a significant decrease in the surrounding electric field intensity. In the non-optimized case, the brain volumes stimulated above 0.2V/m were 99.9% in the region of interest (ROI), and 76.4% in the rest of the gray matter. In contrast, the stimulated volumes were 91.4% and 29.6% for the best optimization case. Additionally, the maximum electric field intensity inside the region of interest was consistently higher than that outside the ROI for all optimized cases.

Significance

Given that the accomplishment of a globally optimal solution requires a brute-force approach, the use of a genetic algorithm can significantly decrease the optimization time and provide usable results. Although the method is promising and the indications are becoming more robust, such that optimal solutions can be achieved at the individual level, there are limitations on what can be achieved using only two electrode pairs.
Duration reproduction under memory pressure: Modeling the roles of visual memory load in duration encoding and reproduction
Authors: Zang Xuelian , Zhu Xiuna , Allenmark Fredrik , Wu Jiao , Müller Hermann J. , Glasauer Stefan , Shi Zhuanghua
Published: February 2022

Duration estimates are often biased by the sampled statistical context, yielding the classical central-tendency effect, i.e., short durations are over- and long duration underestimated. Most studies of the central-tendency bias have primarily focused on the integration of the sensory measure and the prior information, without considering any cognitive limits. Here, we investigated the impact of cognitive (visual working-memory) load on duration estimation in the duration encoding and reproduction stages. In four experiments, observers had to perform a dual, attention-sharing task: reproducing a given duration (primary) and memorizing a variable set of color patches (secondary). We found an increase in memory load (i.e., set size) during the duration-encoding stage to increase the central-tendency bias, while shortening the reproduced duration in general; in contrast, increasing the load during the reproduction stage prolonged the reproduced duration, without influencing the central tendency. By integrating an attentional-sharing account into a hierarchical Bayesian model, we were able to predict both the general over- and underestimation and the central-tendency effects observed in all four experiments. The model suggests that memory pressure during the encoding stage increases the sensory noise, which elevates the central-tendency effect. In contrast, memory pressure during the reproduction stage only influences the monitoring of elapsed time, leading to a general duration over-reproduction without impacting the central tendency.
RNA polymerase redistribution and increased gene dosage support growth in E. coli strains with a minimal number of ribosomal RNA operons
Authors: Fan Jun , El Sayyed Hafez , Pambos Oliver J. , Stracy Mathew , Kyropoulos Jingwen , Kapanidis Achillefs N.
Published: February 2022

Bacterial transcription by RNA polymerase (RNAP) is spatially organised. RNAPs transcribing highly expressed genes locate in the nucleoid periphery, and form clusters in rich media, with several studies linking RNAP clustering and transcription of ribosomal RNA (rrn). However, the nature of RNAP clusters and their association with rrn transcription remains unclear. Here we address these questions by using single-molecule tracking to monitor the subcellular distribution of mobile and immobile RNAP in strains with a heavily reduced number of chromosomal rrn operons (Δrrn strains). Strikingly, we find that the fraction of chromosome-associated RNAP (which is mainly engaged in transcription) is robust to deleting 5 or 6 of the 7 chromosomal rrn operons. Spatial analysis in Δrrn strains showed substantial RNAP redistribution during moderate growth, with clustering increasing at the cell end-caps, where the remaining rrn operons reside. These results support a model where RNAPs in Δrrn strains relocate to copies of the remaining rrn operons. We also show that Δrrn strains experience increased rrn gene dosage in rich media, minimising growth defects due to rrn deletions. Our study further links RNAP clusters and rrn transcription, and offers insight on how bacteria maintain growth in the presence of only 1-2 rrn operons.
How nutrition and energy needs affect bumble bee pollination services: A mathematical model
Authors: Capera-Aragones Pau , Foxall Eric , Tyson Rebecca C.
Published: February 2022

The balance between nutrition and energy needs has an important impact on the spatial distribution of foraging animals. In the present paper, we focus on the case of bumble bees moving around a landscape in search of pollen (to meet nutritional needs) and nectar (to meet energy needs). Depending on the colony demands, bumble bees can concentrate their foraging effort towards either pollen rich flower species or nectar rich flower species. This behaviour allows us to establish a strategy – a spatial landscape design – which can maximize the pollination services of crops that are nutritionally deficient for pollinators by adding nutritionally rich wildflower patches. To do this, we formulate a mathematical partial integro-differential equation model to predict the spatial distribution of foraging bumble bees. We use our model to predict the location, composition and quantity of the wildflower patches adjacent to crop fields that will be most beneficial for crop pollination services. Our results show that relatively small quantities of wildflowers in specific locations with respect to the nest sites and the crop can have a positive impact on pollination services when the composition (i.e., pollen to nectar ratio) of the added wildflowers is significantly different from the composition of the existing crop flowers.
Spatial patterns from a dispersal limitation perspective: revealing biotic interactions
Authors: Kalyuzhny Michael , Lake Jeffrey K. , Ostling Annette M.
Published: February 2022

Local spatial distributions of populations are often studied in comparison to Complete Spatial Randomness (CSR) and are found to be ubiquitously aggregated, likely due to dispersal limitation. Here we theoretically examine the advantages of comparing observed distributions to simulated populations subject only to drift and Dispersal Limitation (DL). Compared to this DL null, local competition produces overdispersion out to surprisingly large scales—much larger than the scale of competitive interactions. Furthermore, strong overdispersion provides a hallmark that a key requirement of stable coexistence is met, as it can only be observed if intraspecific competition is substantially stronger than interspecific competition. Dispersion compared to CSR is insensitive to competition and as a result unreflective of its presence. Hence, we suggest DL as a complement to CSR since the former focuses on biologically relevant spatial scales and has the potential to detect biotic interactions and habitat specificity.
Optimal routing to cerebellum-like structures
Authors: Muscinelli Samuel , Wagner Mark , Litwin-Kumar Ashok
Published: February 2022

The vast expansion from mossy fibers to cerebellar granule cells produces a neural representation that supports functions including associative and internal model learning. This motif is shared by other cerebellum-like structures, including the insect mushroom body, electrosensory lobe of electric fish, and mammalian dorsal cochlear nucleus, and has inspired numerous theoretical models of its functional role. Less attention has been paid to structures immediately presynaptic to granule cell layers, whose architecture can be described as a “bottleneck” and whose functional role is not understood. We therefore develop a general theory of cerebellum-like structures in conjunction with their afferent pathways. This theory predicts the role of the pontine relay to cerebellar cortex and the glomerular organization of the insect antennal lobe. It also reconciles theories of nonlinear mixing with recent observations of correlated granule cell activity. More generally, it shows that structured compression followed by random expansion is an efficient architecture for flexible computation.
Gait stability in ambulant children with cerebral palsy during dual tasks
Authors: Wist Sophie , Carcreff Lena , Bruijn Sjoerd M. , Allali Gilles , Newman Christopher J. , Fluss Joel , Armand Stéphane
Published: February 2022

Aim

The aim of this prospective cross-sectional study with matched controls was to measure the effect of dual tasks on gait stability in ambulant children with cerebral palsy (CP) compared to typically developing (TD) children.

Methods

The children of the CP (n= 20) and TD groups (n=20) walked first without a dual task, then while counting and finally while alternatively naming fruits and animals (DTf/a). They then completed the same cognitive exercises while sitting comfortably. We calculated the distance between the foot placement estimator (FPE) and the real foot placement in the anterior direction (DFPEAP) and in the mediolateral direction (DFPEML) as a measure of gait stability, in a gait laboratory using an optoelectronic system. Cognitive scores were computed. Comparisons within and between groups were analysed with linear mixed models.

Results

The dual task had a significant effect on the CP group in DFPEAP and DFPEML. The CP group was more affected than the TD group during dual task in the DFPEML. Children in both groups showed significant changes in gait stability during dual tasks.

Interpretation

The impact of dual task on gait stability is possibly due to the sharing of attention between gait and the cognitive task. All children favoured a ‘posture second’ strategy during the dual task of alternatively naming animals and fruits. Children with CP increased their mediolateral stability during dual task.
An extended SIR model with vaccine dynamics for SARS-CoV-2 adaptation rate
Authors: Horvat R. , Surić T.
Published: February 2022

The COVID-19 pandemic is caused by infection with a SARS-CoV-2 virus, a RNA virus characterized by high mutation and replication rates. From epidemiological perspective, the trajectory in time of viral adaptation is determined by two opposite forces: (a) proportion of the population who has acquired immunity, exerting thereby a selective pressure on the virus and (b) proportion of infected people in the population, measuring the net viral load in the population. We calculate both the number of advantageous mutations in the population that have accumulated by time t and the amount of viral adaptation transmitted to a susceptible compartment, the latter being called the Evolutionary Infectivity Profile (EIP). To this end we employ first a simple compartmental SIR model with a single parameter describing reduction in transmission due to vaccination. Then we switch to a model which actuates the full vaccine dynamics, including vaccination rate and short duration of immunity. In our models we have never come across a situation where vaccination plays a dominant role in driving new SARS-CoV-2 variants. Nevertheless if the vaccination rate is not high enough, the EIP would continuously grow with time, pointing to a fruitful field for proliferation of genetically variable SARS-CoV-2 viruses.
In vivo white matter microstructure in adolescents with early-onset psychosis: a multi-site mega-analysis via the ENIGMA Consortium
Authors: Barth Claudia , Kelly Sinead , Nerland Stener , Jahanshad Neda , Alloza Clara , Ambrogi Sonia , Andreassen Ole A , Andreou Dimitrios , Arango Celso , Baeza Inmaculada , Banaj Nerisa , Bearden Carrie E , Berk Michael , Bohman Hannes , Castro-Fornieles Josefina , Chye Yann , Crespo-Facorro Benedicto , de la Serna Elena , Díaz-Caneja Covadonga M , Gurholt Tiril P , Hegarty Catherine E , James Anthony , Janssen Joost , Johannessen Cecilie , Jönsson Erik G , Karlsgodt Katherine H , Kochunov Peter , Lois Noemi G , Lundberg Mathias , Myhre Anne M , Pascual-Diaz Saül , Piras Fabrizio , Smelror Runar E , Spalletta Gianfranco , Stokkan Therese S , Sugranyes Gisela , Suo Chao , Thomopoulos Sophia I , Tordesillas-Gutiérrez Diana , Vecchio Daniela , Wedervang-Resell Kirsten , Wortinger Laura A , Thompson Paul M. , Agartz Ingrid
Published: February 2022

Background

Emerging evidence suggests brain white matter alterations in adolescents with early-onset psychosis (EOP; age of onset <18 years). However, as neuroimaging methods vary and sample sizes are modest, results remain inconclusive. Using harmonized data processing protocols and a mega-analytic approach, we compared white matter microstructure in EOP and healthy controls (CTR) using diffusion tensor imaging (DTI).

Methods

Our sample included 321 adolescents with EOP (mean age: 16.3 ± 1.4 years, 46.4% females) and 265 adolescent CTR (mean age: 16.0 ± 1.7 years, 57.7% females) pooled from nine sites. All sites extracted mean fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD), and axial diffusivity (AD) for 25 white matter regions of interest per participant. ComBat harmonization was performed for all DTI measures to adjust for scanner differences. Multiple linear regression models were fitted to investigate case-control differences and associations with clinical variables in regional DTI measures.

Results

We found widespread lower FA in EOP compared to CTR, with the largest effect sizes in the superior longitudinal fasciculus (Cohen’s d = 0.37), posterior corona radiata (d = 0.32), and superior fronto□occipital fasciculus (d = 0.31). We also found widespread higher RD and more localized higher MD and AD. We detected significant effects of diagnostic subgroup, sex, and duration of illness, but not medication status.

Conclusion

Using the largest EOP DTI sample to date, our findings suggest a profile of widespread white matter microstructure alterations in adolescents with EOP, most prominently in male patients with early-onset schizophrenia and patients with a shorter duration of illness.