Browse Articles

Fixation drift increases as a function of time-on-task in a brief saccade tracking study

Ocular fixations contain microsaccades, drift and tremor. We report an increase in the slope of linear fixation drift as a function of time-on-task (TOT). We employed a large dataset (322 subjects, multiple visits per subject). Subjects performed a random saccade task. The task, in which the target dot jumped randomly every one sec, was 100 sec in duration. For each fixation, we regressed eye position against time across multiple segment lengths (50, 100, 300, and 500 ms). We started with the first sample and continued until no further regressions were possible based on the segment length being evaluated. For each segment length, each fixation was characterized by a single value: the maximum slope over the segment length. The slopes were expressed in deg/sec. We were not interested in the direction of the linear drift, so we took the absolute value of the slope as a measure. For data analysis, each 100 sec task was divided into five 20 sec epochs. In an attempt to partially replicate an earlier study of fixation drift over time [1], we also measured drift as the mean velocity of an eye-position signal that had been low-pass filtered at 30 Hz. We found that both methods detected significant drift over our task. For each visit, subjects were tested in two sessions, approximately 20 min apart. Generally, we found statistically significant session effects indicating that drift started at a higher level and increased at a higher rate over the second session. We report that the mean velocity method detects distinctive types of drifting fixation trajectories including curvilinear drift and irregular oscillation. Our findings extend the observations of increased drift over time by [1] to other measures of drift and to a much shorter time interval (100 sec vs two hrs) and a simpler task.

Association between Platelet Count and In-Hospital Mortality in Critical Patients with Multiple Myeloma: A Cohort Study

Background Multiple myeloma (MM) is a malignant blood disease characterized by the abnormal proliferation of immature plasma cells in the bone marrow. Changes in platelet counts (PLT) may significantly impact patient mortality. This study investigates the correlation between platelet counts and mortality rates in critically ill multiple myeloma patients admitted to the Intensive Care Unit (ICU). Methods A retrospective cohort study was conducted with 242 patients diagnosed with MM. Data on platelet count(PLT), red blood cell count(RBC), serum calcium levels, International Normalized Ratio (INR), Sequential Organ Failure Assessment (SOFA) Score, Simplified Acute Physiology Score II (SAPS II), and comorbidities were collected. The study captured the highest and lowest values of laboratory data for patients during their ICU admission. Logistic regression analysis and smooth curve fitting technique were used for analysis. Subgroup analysis was applied to detect cross interactions. Sensitivity analysis was applied to detect consistency. Results When the minimum PLT (PLT-min) were treated as a continuous variable at every 10 × 109/L, the multivariate logistic regression analysis revealed that decreased PLT-min levels was an independent risk factor for mortality rate of critically ill patients with MM [Odds ratio (OR)=0.94, 95% confidence interval (95% CI): 0.89‑0.99, p = 0.023]. Additionally, when PLT-min levels were categorized into tertiles as <95 × 109/L (group 1), 95–160 × 109/L (group 2), and >160 × 109/L (group 3), a decrease in PLT-min levels was also associated with an increasing trend in hospital mortality rate. Compared to group 1, the OR values of group 2 and group 3 were 0.40((95% CI:0.15–1.07, p = 0.069) and 0.30 (95% CI: 0.11‑0.82, p = 0.020). The relationship between PLT-min and in-hospital mortality was found to be nonlinear. Subgroup analysis showed no significant interactions. Similar results were obtained when analyzing the association of maximum PLT(PLT-max) and mortality rate. Conclusions In MM patients in ICU, both minimum and maximum PLT were significantly associated with an increased risk of in-hospital mortality in critical ill patients with MM. These findings are important and warrant further investigation.

KIFC1 inhibition: Exploring the potential of propolis-derived small molecules for targeting cancer progression through in silico analysis

Propolis, a resinous compound produced by bees, possesses diverse medicinal properties and has gained significant attention for its potential in cancer therapy. This study investigated the therapeutic significance of propolis-derived compounds targeting the kinesin-like protein KIFC1, a motor protein overexpressed in various cancers, using a multistep computational methodology. Therefore, it is essential to utilize different in silico methods to predict their therapeutic potential. A 3D library of propolis-derived compounds sourced from previously published literature was compiled and screened for physicochemical properties, drug-likeness, and pharmacokinetic predictions using the SwissADME and BOILED-Egg permeation predictive model. Pharmacokinetic computations were used to filter out compounds that lacked drug-likeness attributes. KIFC1 3D homology model was selected from the AlphaFold database, its stereochemical properties were assessed and validated. Virtual screening was performed to identify the high-binding affinity-based top-ranked compounds. Furthermore, the active residues present in the druggable cavities were identified using the Cavity Blind (CB) docking tool to investigate grid-box-based residue-specific molecular docking and simulation analysis. We found five common propolis-derived compounds following the druglikeness rule, and having HBA (high binding affinity) for the KIFC1 protein, were subjected to CB docking to identify druggable binding pockets (recognition of consensus residues) on KIFC1 as well as residue-specific molecular docking and simulation. Grid-box-based docking experiments for exploring the molecular interactions of the five compounds above validated the inhibitory effects of kaempferide (∆G = −7.35 kcal/mol and Ki = 4.12 μM), luteolin (∆G = −6.74 kcal/mol and Ki = 11.48 μM), Izalpinin (∆G = −6.33 kcal/mol and Ki = 22.9 μM), 4’,5,7-Trihydroxy-3,6-dimethoxyflavone (∆G = −6.14 kcal/mol and Ki = 31.71 μM), and 6-methoxykaempferol (∆G = −6.55 kcal/mol and Ki = 15.81 μM). Molecular dynamics simulation analysis at 100 nanoseconds examined the binding modes of five screened compounds and predicted molecular interactions with KIFC1 protein residues. Two propolis-derived compounds, 4’,5,7-trihydroxy-3,6-dimethoxyflavone and 6-methoxy kaempferol, showed significant interactions with KIFC1 residues and exhibited stable binding pattern. MD simulations analysis showed minor variation in root-mean-square deviation and fluctuation, confirming their equilibrium with KIFC1 protein. The study enhances understanding of propolis compounds’ inhibitory effects on KIFC1 protein, providing insights for potential treatment approaches and requiring further experimental (in vivo and in vitro) as well as clinical validation.

Predictors of institutional delivery service utilization among women in Northern region of Ghana

Introduction An increase in home delivery among expectant mothers may likely lead to high maternal and newborn morbidities and mortalities. Despite the policy on free maternal healthcare in Ghana under the National Health Insurance Scheme (NHIS) since 2007, more than 25% of deliveries still occur outside health facilities in northern Ghana. Use of safe and effective delivery services including place of delivery is an important component of the Safe Motherhood concept. Hence, assessing predictors of institutional delivery could contribute to improving birth outcomes in the Northern Region. Methods We conducted a community-based cross-sectional survey of 310 women aged 15–49 years old who had given a live birth between January 2022 and January 2023, using a simple random sampling approach. Using a semi-structured questionnaire, we collected data on mothers’ background characteristics, place of delivery for their most recent birth and reported health facility factors. Descriptive analyses and multiple logistic regression models were performed to identify factors associated with institutional delivery at a 5% significance level. Results Of 310 women in the study, the prevalence of institutional delivery was 79%(245) in their most recent births. More than 60%(200/310) of the women were married and 53%(163/310) had no formal education. Being married (adjusted odds ratio {aOR}=2.8, 95%CI:1.48–5.32), the presence of skilled health personnel at post (aOR=2.9, 95%CI:1.54–5.43), reported positive attitude of health workers towards their clients (aOR=1.8, 95%CI:1.03–3.23) and positive community perception of health facility delivery (aOR=3.8, 95%CI:1.64–8.71) were associated with increased odds of institutional delivery. Conclusions Our study identified multiple predictors of institutional delivery; marital status, the presence of skilled health personnel at health facilities, the perceived attitude of health workers and community perception. The research team organized discussions on institutional delivery services with community members in five selected districts in the region. We recommend the Ministry of Health should develop well-defined care packages targeting unmarried pregnant women, negative health worker attitudes and negative community perceptions.

Observing anyonization of bosons in a quantum gas

Abstract Anyons 1,2 are low-dimensional quasiparticles that obey fractional statistics, hence interpolating between bosons and fermions. In two dimensions, they exist as elementary excitations of fractional quantum Hall states 3–5 and are believed to enable topological quantum computing 6,7 . One-dimensional anyons have been theoretically proposed, but their experimental realization has proven to be difficult. Here we observed emergent anyonic correlations in a one-dimensional strongly interacting quantum gas, resulting from the phenomenon of spin–charge separation 8–10 . A mobile impurity provides the necessary spin degree of freedom to engineer anyonic correlations in the charge sector and simultaneously acts as a probe to reveal these correlations. Starting with bosons, we tune the statistical phase to transmute bosons through anyons to fermions and observe an asymmetric momentum distribution 11–14 , a hallmark of anyonic correlations. Going beyond equilibrium conditions, we observed dynamical fermionization of the anyons 15 . This study opens the door to the exploration of non-equilibrium anyonic phenomena in a highly controllable setting 15–17 .

Beyond the medical file: A scoping review on patients’ perspectives on depression treatment in primary care

Objectives Depressive disorders are common in the primary care setting. Despite its high prevalence, depression treatment in primary care is less guideline-oriented compared to specialized settings, which often makes it less efficient. Current research has focused on explanations on the practitioner’s side but has neglected the patient’s perspective and its effect on treatment largely. Methods We conducted a scoping review on the electronic databases Medline and Psycinfo. Eligible publications contained information of the patients’ perspective on depression treatment in primary care in OECD member states. Publications until August 2nd 2023 were considered. Results After the removal of duplicates, the search yielded 14.059 articles, of which 232 were included. Current literature focuses on behavioral and obvious measures like satisfaction, and on patient-sided barriers and facilitators to adherence. Other treatment-related behaviors are less researched. Patients with undiagnosed depression often report exclusively or mainly physical symptoms in general practice. Conclusion This review provides a comprehensive framework for the concept. Research on barriers and facilitators to depression treatment in primary care is still inconclusive. Educating patients and addressing stigmatizing beliefs are promising targets to promote the seeking out, initiation of, and adherence to treatment. Being aware of a hidden depression when somatic symptoms are present, can help to detect more cases. Registration This review is registered via OSF (https://osf.io/p9rnc).

How the brain spies on the gut: with help from newfound immune cells

Blocking a key node in cancer signalling unlocks therapeutic potential

Developmental transcriptomics of the Firebrat: Exploring developmental expression patterns and morphology during the embryogenesis of Thermobia domestica

Understanding the development of early-diverging lineages is crucial for inferring evolutionary context in evolutionary developmental biology. Thermobia domestica (the firebrat), a member of Zygentoma, holds particular significance to insect phylogenetics due to its position as a sister group to all winged insects (Pterygota). We explore its development by reporting on the embryonic morphology using DAPI staining at 14 selected timepoints throughout development, which lasts 10 days. At each timepoint, RNA sequencing was conducted to perform a large-scale transcriptomic analysis. Differential gene expression analysis and gene ontology (GO) enrichment studies revealed global expression patterns and linked biological processes to specific developmental stages. Key findings include the identification of major transcriptional turning points during three developmental stages: The maternal to zygotic transition between 16 and 24 hours after egg-laying (hAEL), katatrepsis between 72 and 96 hAEL, and hatching between 216 and 240 hAEL. Additionally, the GO study mapped the timing of biological processes, such as cleavage, blastoderm formation, dorsal closure, and organogenesis, particularly tracheal and muscular development. These insights establish a robust temporal framework for T. domestica embryogenesis and provide a foundation for inferring ancestral and derived developmental traits in insects. The dataset serves as a valuable library for genetic studies and reference for comparative evo-devo studies with other insect species.

Electrical switching of a p-wave magnet 

Targeting the SHOC2–RAS interaction in RAS-mutant cancers

Genomic determinants of antigen expression hierarchy in African trypanosomes

Abstract Antigenic variation is an immune evasion strategy used by many different pathogens. It involves the periodic, non-random switch in the expression of different antigens throughout an infection. How the observed hierarchy in antigen expression is achieved has remained a mystery1,2. A key challenge in uncovering this process has been the inability to track transcriptome changes and potential genomic rearrangements in individual cells during a switch event. Here we report the establishment of a highly sensitive single-cell RNA sequencing approach for the model protozoan parasite Trypanosoma brucei. This approach has revealed genomic rearrangements that occur in individual cells during a switch event. Our data show that following a double-strand break in the transcribed antigen-coding gene—an important trigger for antigen switching—the type of repair mechanism and the resultant antigen expression depend on the availability of a homologous repair template in the genome. When such a template was available, repair proceeded through segmental gene conversion, creating new, mosaic antigen-coding genes. Conversely, in the absence of a suitable template, a telomere-adjacent antigen-coding gene from a different part of the genome was activated by break-induced replication. Our results show the critical role of repair sequence availability in the antigen selection mechanism. Furthermore, our study demonstrates the power of highly sensitive single-cell RNA sequencing methods in detecting genomic rearrangements that drive transcriptional changes at the single-cell level.

Assessing the impact of internet-based cognitive behavioral therapy on sexual dysfunction: A systematic review protocol

Introduction Sexual dysfunction (SD), a prevalent health concern, can significantly impact an individual’s overall well-being and intimate relationships. Internet-based cognitive behavioral therapy (ICBT) has emerged as a promising and accessible intervention for addressing this issue. Therefore, this review aims to assess the impact of ICBT on SD among adults. Methods and analysis Searches will be conducted on PubMed, Scopus, EMBASE, Web of Science (ISI), Trialserach.who.int, and ClinicalTrials.gov, as well as search engines like Google Scholar. This review will focus on randomized clinical trials evaluating the efficacy of ICBT in addressing SD. The initial search and subsequent removal of duplicate entries will be conducted by the principal investigator. Two independent reviewers will then perform study selection, data extraction, and two independent assessors will assess methodological quality using the Cochrane risk of bias assessment tool 2 (RoB 2). The final data synthesis strategy will be contingent upon the characteristics and availability of the included studies. PROSPERO registration number CRD42023431255. Ethical code IR.SHMU.REC.1403.079.

Bed bugs boomed as the world’s first cities did

Shifts in phytoplankton community structure across oceanic boundaries

Phytoplankton communities play an important role in marine food webs and biogeochemical cycles. The transition zones between ocean gyres and surrounding waters represent critical ecological boundaries where environmental gradients drive significant shifts in phytoplankton community structure. This study investigates how nutrient availability and temperature shape the size distribution and composition of small phytoplankton (< 5 μm) communities across the North Pacific Subtropical Gyre (NPSG) boundaries, testing several ecological hypotheses that explain phytoplankton size distribution patterns in relation to environmental variability. We used high-resolution, underway flow cytometry data collected during eight oceanographic cruises from 2016 to 2021 to assess changes in phytoplankton biomass and growth rate across the gyre boundaries. The cyanobacterium Prochlorococcus dominated within the gyre, with biomass ranging from 3.2 to 13.1 μgC L−1, and its relative contribution to total phytoplankton biomass varied among cruises (31% to 81%, average 60 ± 16%). Prochlorococcus growth rates were significantly higher within the gyre (0.43 ± 0.18 per day) than outside the gyre (0.28 ± 0.16 per day) (one-sided t-test, p < 0.001). Northward in the gyre, Prochlorococcus biomass and growth rates declined. Some variations in biomass and growth rates were observed southward and eastward, with biomass ranging from 3 to 10 μgC L−1 and growth rate ranging from 0.2 to 0.6 per day. Outside the NPSG, total phytoplankton biomass increased, with nanoeukaryotes becoming the predominant contributors (up to 71%, 9.1 ± 7.3 μgC L−1). Picoeukaryote biomass also increased outside the gyre (up to 28 ± 12% of total biomass). Nutrient concentrations increased by nearly two orders of magnitude outside the NPSG, coinciding with the shift towards larger phytoplankton. The dominance of Prochlorococcus within the gyre emphasizes its adaptation to oligotrophic conditions, while the shift towards larger size classes outside the gyre likely reflects the relatively higher nutrient availability. The relatively low abundance of Synechococcus even in nutrient-rich regions suggest that that factors beyond nutrient availability, such as grazing, may influence its distribution. These findings have implications for understanding how phytoplankton communities will respond to future changes in oceanographic conditions, such as warming and altered nutrient regimes.

Determinants of jaundice severity in neonates admitted at a Teaching Hospital in Ghana

Background Severe neonatal jaundice (NJ) is associated with significant morbidity and mortality globally with low and, middle income countries having a greater burden. Increased red blood cell destruction and reduced bilirubin elimination increase the risk of severe NJ development. Severe NJ predisposes the neonates to bilirubin-induced encephalopathy leading to kernicterus-spectrum disorders in the long-term. Objective The study was undertaken to determine the risk factors associated with development of significant jaundice in neonates at a teaching hospital in Ghana. Materials and methods A retrospective review of patient electronic medical records at the paediatric ward and Neonatal Intensive Care Unit (NICU) at the Cape Coast Teaching Hospital (CCTH) was conducted. Demographics, initial serum bilirubin concentration (total, direct and indirect), full blood count, G6PD status and outcome data were collected. Binary logistic regression models were used to determine the risk factors of NJ severity which was the main outcome. Stata 18.0 software was used for the analysis. Results Data on two hundred and ninety-three (293) neonates were extracted of which 247 were used for further analyses after data cleaning. Of these, 30% had significant NJ defined as initial TSB concentration ≥ 213micromol/L. Significant NJ was significantly associated with admission after 24 hours of birth (aOR = 2.45; 95% CI:1.26,4.77; p = 0.009) and full/partial defect G6PD (aOR = 2.21; 95% CI:1.03,4.71; p = 0.041). Conclusions Significant NJ is common and significantly associated with admission after 24 hours of life and G6PD full/partial defect at Cape Coast Teaching Hospital.

Progress in developing a bark beetle identification tool

This study presents an initial model for bark beetle identification, serving as a foundational step toward developing a fully functional and practical identification tool. Bark beetles are known for extensive damage to forests globally, as well as for uniform and homoplastic morphology which poses identification challenges. Utilizing a MaxViT-based deep learning backbone which utilizes local and global attention to classify bark beetles down to the genus level from images containing multiple beetles. The methodology involves a process of image collection, preparation, and model training, leveraging pre-classified beetle species to ensure accuracy and reliability. The model's F1 score estimates of 0.99 and 1.0 indicates a strong ability to accurately classify genera in the collected data, including those previously unknown to the model. This makes it a valuable first step towards building a tool for applications in forest management and ecological research. While the current model distinguishes among 12 genera, further refinement and additional data will be necessary to achieve reliable species-level identification, which is particularly important for detecting new invasive species. Despite the controlled conditions of image collection and potential challenges in real-world application, this study provides the first model capable of identifying the bark beetle genera, and by far the largest training set of images for any comparable insect group. We also designed a function that reports if a species appears to be unknown. Further research is suggested to enhance the model's generalization capabilities and scalability, emphasizing the integration of advanced machine learning techniques for improved species classification and the detection of invasive or undescribed species.

Unconventional solitonic high-temperature superfluorescence from perovskites

Body mass index mediates the association between sleep duration and academic performance: An evidence in Chinese adolescent students

Background Academic performance serves as a crucial indicator for evaluating adolescents’ educational outcomes in China, which prompting parents and schools to place significant emphasis on students’ academic achievements. However, the pursuit of excellent academic performance often leads to inadequate sleep duration, while the body mass index (BMI) is also disregarded when prioritizing academic achievement. This study aims to examine the association between sleep duration and academic performance and to explore the mediating role of body mass index (BMI) among adolescent students in rural and urban areas of China. Methods The study utilized baseline (2013–2014 academic year) and follow-up survey data (2014–2015 academic year) from the China Education Panel Study (CEPS). A total of 7,218 adolescent subjects aged between 12 and 14 were recruited using multi-stage random probability proportional to size sample (PPS) sampling, providing demographic, sleep duration, and body mass index (BMI) information. Descriptive analysis, Ordinary Least Square (OLS), and Product of Coefficients Approach were used to estimate the association and mediating role between sleep duration, BMI and academic performance. Results The sleep duration has significantly influenced the academic performance of adolescent students, (p < 0.01). A 10-minute increase in sleep duration was associated with a 6.3% decrease in academic performance for rural-urban students (β = -0.063, p < 0.01). Subgroup analyses further demonstrated that a 10-minute increase in sleep duration led to an 8.5% decrease in academic performance for rural adolescent students (β = -0.085, p < 0.01), while urban students experienced a 6.7% decrease under similar circumstances (β = -0.067, p < 0.05). Body mass index (BMI) negatively influenced students’ academic performance (β = -0.071, p < 0.01) and mediates the relationship between sleep duration and academic performance (β = 0.112, p < 0.001). Conclusions The sleep duration has negatively influenced rural-urban adolescent students’ academic performance in China, however, this influence was indirect when added the variable BMI into the model. The BMI played a mediating role in the relationship between sleep duration and academic performance.

Dating the evolution of oxygenic photosynthesis using La-Ce geochronology