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Spatiotemporal structure of SARS-CoV-2 mutational frequencies in wastewater samples from Ontario

Starting October 2021, the Ontario wastewater surveillance initiative has used next-generation sequencing (NGS) to monitor SARS-CoV-2 RNA in wastewater samples. The fragmented and heterogeneous nature of these data precludes using comparative methods that require full-length genome sequences. In this study, we investigate the utility of the inner product of the vectors of mutation frequencies to quantify the temporal and spatial structure of these data. Raw sequence data were trimmed and mapped to the SARS-CoV-2 reference genome to extract mutation frequencies and coverage statistics. These data were filtered for samples with incomplete metadata, positions with insufficient coverage (> 100 reads), or mutations with frequencies below 1%. For every pair of samples, we calculated the inner product of the respective mutation frequency vectors, and normalized the result to obtain a cosine distance. In total, we processed 1,619 samples from October 2021 to June 2023. The average depth was 7,693 reads, with mean coverage of 24,853 nt. A total of 241,078 mutations were detected in these samples. We restricted our analysis to 20 consecutive months with samples from at least one health region per month. A projection of the resulting cosine distance matrix revealed substantial temporal structure largely driven by the rapid spread of variants of concern. Genetic similarity, as quantified by the normalized dot product of mutation frequencies, was significantly negatively correlated with the geographic distance between sampling locations. These results suggest that spatial differentiation in the genomic variation of SARS-CoV-2 among wastewater samples can be measured, even at the relatively small scale of a single province.

Author Correction: Morphine promotes non-small cell lung cancer progression by downregulating E-cadherin via the PI3K/AKT/mTOR pathway

Reimagining the role of teaching-focused faculty in research-intensive universities: The evolution of scholarly expectations and departmental influence

Research-intensive universities aim to conduct cutting-edge research while providing the knowledge and skills necessary to prepare students to excel in their respective fields. As student enrollments surge, many institutions have turned to hiring teaching-focused faculty. In the University of California (UC) system, there exists a unique position known as the Professor of Teaching (PoT). This position is tenure-eligible, and members are required to engage in classroom teaching, scholarly activities, and service responsibilities. To shed light on the background characteristics, roles and perceptions of the impact of teaching-focused faculty in research-intensive institutions, we collected survey data from STEM PoT faculty across the UC system. We employed a mixed methods approach, using descriptive and inferential statistics to analyze quantitative responses and thematic analysis to examine open-ended qualitative data. Our analysis shows that pre-tenure PoTs place greater emphasis on scholarly activities relative to their peers who have been in the role for longer. However, their training and the institutional resources provided may not align with expectations for scholarly activities. Additionally, we find that PoTs who engage in research perceive that they have a more significant impact on their colleagues’ teaching. This finding underscores the value of research, even for teaching-focused faculty. This study informs the evolving landscape of teaching-focused faculty within research-intensive universities and provides recommendations for administrators considering how to ensure that their institutions are fulfilling their educational mission.

Patterned invagination prevents mechanical instability during gastrulation

Abstract Mechanical forces are crucial for driving and shaping tissue morphogenesis during embryonic development1–3. However, their relevance for the evolution of development remains poorly understood4. Here we show that an evolutionary novelty of fly embryos—the patterned embryonic invagination known as the cephalic furrow5–7—has a mechanical role during Drosophila gastrulation. By integrating in vivo experiments and in silico simulations, we demonstrate that the head–trunk boundary of the embryo is under increased compressive stress due to the concurrent formation of mitotic domains and germ band extension and that the cephalic furrow counteracts these stresses, preventing mechanical instabilities during gastrulation. Then, by comparing the genetic patterning of species with and without the cephalic furrow, we find evidence that changes in the expression of the transcription factor buttonhead are associated with the evolution of the cephalic furrow. These results suggest that the cephalic furrow may have evolved through the genetic stabilization of morphogenesis in response to the mechanical challenges of dipteran gastrulation. Together, our findings uncover empirical evidence for how mechanical forces can influence the evolution of morphogenetic innovations in early development.

Coherent control of optical lattices and optical unit cells in atomic medium by counter propagation of Laguerre Gaussian beams

Magnetic field sensing for 2D fault localization in underground power cables

Localizing faults in underground cables is a two-dimensional inverse problem, including the depth as the vertical dimension and the horizontal distance from the supply point. In this paper, a new approach based on magnetic field sensing is developed to accurately locate faults in underground cables without physically accessing them. Three types of fault are addressed, line-to-ground fault (LGF), leakage current fault (LCF), and line-to-line fault (LLF). Based on magnetic field sensing, the cable is first localized. Afterwards, the depth is calculated using the Quotient method and finally, the horizontal distance is determined using Kirchhoff’s law (KVL). The simulation results show average errors of 5.25%, 4.77%, and 3.53% for LGF, LCF, and LLF. respectively, while the experimental results yield errors of 20% and 29% for LGF and LLF. These findings highlight the reliability of the proposed approach. Additionally, since the method requires only a single magnetic field sensing device with minimal computational effort, it offers a practical and cost-effective solution for the location of underground cable faults.

Spatial modelling of groundwater potential zones in the Neyyar Basin using machine learning and morphometric analysis

Comparative analysis of the push-out bond strength of fiber posts: Immediate vs. delayed post-space preparation with two obturation techniques

Objectives The objective of this study was to assess the impact of immediate and delayed post- space preparation on the push-out bond strength (PBS) of fiber posts by employing two root canal obturation techniques: continuous wave of condensation (CWC) and single-cone (SC) obturation. Materials and methods Forty-eight human maxillary premolar teeth were instrumented, and the samples were divided into four groups according to the obturation technique and the time of post-space preparation. SC and CWC underwent immediate post-space preparation; and CWC and SC underwent delayed post-space preparation. The smear layer and dentine tubules from the apical, middle, and cervical regions of the samples were observed via scanning electron microscopy (SEM) and the %VoidsVol of the medium 4-mm fiber posts of each group was calculated via micro-computed tomography (CT). Each post space of the root was subsequently cut into slices, resulting in three 1-mm slices at 3 different depths (apical to the cervical region) and subjected to a push-out test. The failure mode was assessed. The data were analysed via the Shapiro-Wilk test, one-way analysis of variance and Bonferroni correction tests. Results In terms of depth from the apical to the cervical region, SC following immediate post-space preparation exhibited greater bond strength than did CWC following delayed post-space preparation. SEM images revealed that the smear layer was completely visible. In the SC with immediate post-space preparation group, the smear layer could be partially removed from the apical, middle and cervical regions of the samples and the outlines of the dentine tubules were visible. The percentage volume of the voids of the medium 4-mm fiber posts of the four groups and the samples in the three directions were not significantly different. No significant differences were observed in the CWC or SC obturation technique regardless of the time of post-space preparation or in immediate or delayed post-space preparation with different obturation techniques. Conclusions SC followed by immediate post-space preparation provided better bond strength of fiber posts to intraradicular dentine than did CWC followed by delayed post-space preparation.

Defending Ohuira Bay, Mexico

Identifying TP53RK as a key regulator of colorectal cancer survival and a potential therapeutic target

Appropriate complementary feeding practices and associated factors among mothers with infants aged 6–8 months in West Gojjam Zone, Northwest Ethiopia: A mixed methods study

Background Appropriate complementary feeding is critical to improve children’s nutrition, health, and development. However, these practices are notably low among Ethiopian mothers. Therefore, this study aimed to assess appropriate complementary feeding practices and associated factors among mothers with infants aged 6–8 months in West Gojjam Zone, Northwest Ethiopia. Methods A community-based cross-sectional study including 802 mothers with infants aged 6–8 months was conducted from June to December 2023. Study participants were selected using a cluster sampling technique. Quantitative data were collected using structured questionnaires, while semi-structured interview guides were employed for qualitative data collection. Multivariable logistic regression was used to identify factors associated with appropriate complementary feeding practices. A p-value <0.05 was considered statistically significant. Qualitative data were thematically analyzed using Open Code 4.03 software. Results The prevalence rate of appropriate complementary feeding practices among mothers with infants aged 6–8 months was only 9.6% (0.096; 95% CI: 0.077, 0.119). A month increase in the infant’s age [AOR = 2.92, 95% CI: (1.99, 4.29)], postnatal counseling on complementary feeding [AOR = 2.64, 95% CI: (1.46, 4.75)], feeding animal-source foods on fasting days [AOR = 2.60, 95% CI: (1.20, 5.66)], higher household wealth: being rich [AOR = 3.13, 95% CI: (1.32, 7.40)], and richest [AOR = 3.16, 95% CI: (1.34, 7.49)], and perceived susceptibility [AOR = 2.45, 95% CI: (1.39, 4.31)] were predictors of appropriate complementary feeding practices. Additionally, excessive workload, misconceptions, and poverty were barriers to these practices. Conclusion Most mothers in this study practiced inappropriate complementary feeding. Therefore, healthcare providers should strengthen postnatal counseling on complementary feeding and promote provision of age-appropriate animal-source foods on fasting days. Improving households’ economic status and mothers’ understanding of the risks associated with inappropriate complementary feeding practices is crucial. Collaboration among stakeholders, including women’s affairs and religious leaders, can help reduce mothers’ workload and address misconceptions about complementary feeding practices.

Development and validation of a predictive model for diabetic peripheral neuropathy with type 2 diabetes mellitus in Xinjiang, China

Trends and outcomes of cardiac arrest and extracorporeal membrane oxygenation during the COVID-19 pandemic in the United States

Background The COVID-19 Pandemic challenged the healthcare system worldwide, but its effect on outcomes of cardiac arrest (CA) and extracorporeal membrane oxygenation (ECMO) use are understudied. We examined trends in CA, ECMO use and survival, and evaluated the impact of receiving care during the COVID-19 Pandemic on outcomes following CA. We also evaluated the impact of COVID-19 infection on outcomes following CA. Methods Adults with out-of-hospital (OHCA) or in-hospital cardiac arrest (IHCA) were identified in the 2016−2020 National Inpatient Sample. For primary analysis, CA patients without COVID-19 were divided into Pre-Pandemic and Pandemic time-periods. For secondary analysis, CA patients treated during the Pandemic time-period were divided by COVID-19 infection status. Generalized linear models were used to evaluate associations between Pandemic time-period or COVID-19 infection with in-hospital mortality. Results Of 1,320,020 non-COVID-19 CA patients, 19.1% were managed during the Pandemic. From 2016−2019, CA incidence increased from 696 to 771 per 100,000 hospitalizations, and disproportionately increased to 1,023 per 100,000 hospitalizations by the end of 2020. Mortality for IHCA was stable prior to the Pandemic, but increased from 67.4% to 75.4% by the end of 2020, while mortality for OHCA was stable. ECMO use increased from 2016 to 2019 for OHCA and IHCA, declined during the second quarter of 2020, and recovered to pre-Pandemic levels by the end of 2020. After risk-adjustment, care during the Pandemic was associated with 1.2-fold greater odds of mortality after CA for non-COVID-19 patients. Among 277,975 patients experiencing CA during the Pandemic, 19.6% had concomitant COVID-19 infection. After risk-adjustment, COVID-19 infection was associated with 3.9-fold greater odds of mortality after CA. Conclusion CA incidence and mortality increased during the COVID-19 Pandemic, while ECMO use declined, emphasizing the need to improve care of CA and ECMO patients. COVID-19 patients with CA had dismal outcomes, suggesting no role for ECMO in this population.

Enhanced short-term carbon emission forecasting via hybrid decomposition-denoising modeling

Antibacterial property of lead telluride quantum dot layer fabricated on glass substrate

Lead Telluride (PbTe) is a narrow band gap semiconductor alloy with excellent thermoelectric properties for several energy harvesting applications. However, the antibacterial properties of PbTe quantum dots (QDs) have not been investigated. PbTe QDs were synthesized using simple spin-coating method and deposited on Titanium dioxide layered ITO glass substrates. The resulting layers of PbTe QDs on the substrates were characterized using high-resolution scanning electron microscope, energy-dispersive X-ray spectroscopy, Fourier transform infra-red spectroscopy and contact angle measurement. The characterization results showed thin layers of PbTe quantum dots with mean sizes 6.1 ± 0.5 nm, 9.8 ± 0.7 nm, and 13.2 ± 1.1 nm and reduced surface wettability. PbTe QDs were tested for their antibacterial activity against Gram-positive bacteria Staphylococcus aureus and Gram-negative Escherichia coli, Salmonella Paratyphi B and Pseudomonas aeruginosa. The antibacterial effect of the QDs was estimated using the zones of inhibition to bacterial growth. The results show excellent antibacterial activity of PbTe QDs towards Gram-negative bacteria. FTIR micro-spectroscopy suggests disruption of cell boundaries as possible mechanism of antibacterial action of PbTe QDs. Given the demonstrated antibacterial effectiveness, the PbTe QDs can be considered for nanocoating bacterial-prone surfaces like solar panels to minimize bacterial colonization and improve system performance.

Efficient fusion transformer model for accurate classification of eye diseases

Comprehensive analysis and effective treatment of plugging in shale gas wells: From composition identification to removal agent optimization

With the extensive exploitation of shale gas fields in southern Sichuan, China, the Weiyuan Area – a key production zone within this region – has experinced a growing gas well plugging problem, which significantly hampers production efficiency. This study presents a comprehensive analysis of plugging problems in this area. Plugging samples were obtained from typically affected gas wells and subjected to a suite of analytical techniques. Results indicated that plugging materials were predominantly inorganic, primarily comprising iron-based impurities and mineral scale deposits, while organic components—present in minor proportions—primarily composed of long-chain alkanes. The formation of these plugs is attributed to downhole corrosion, high-salinity formation water, and complex chemical interactions occurring within the wellbore. In response, specialized plugging removal agents were developed: an organic composite acid-organic solvent system achieved up to 98% dissolution efficiency for iron oxide-dominated plugs; a chelating agent based on CDTA was optimized for iron sulfide-based plugging; and the DTPA-based system exhibited superior dissolution efficiency for barium sulfate/calcium carbonate scale deposits. This research provides a scientific basis for effectively mitigating plugging issues in comparable shale gas fields.

Power quality improvement and energy management in hybrid microgrids using a dual-optimization approach

A study protocol of the rehabilitative efficacy of cardiovascular ultrasound therapy after percutaneous coronary intervention in patients with coronary artery disease: A multicenter, parallel-group, randomized controlled study

Background Coronary artery disease (CAD) is a leading cause of mortality and disability, placing heavy burdens on healthcare systems. Although cardiovascular ultrasound therapy has demonstrated effectiveness and safety in improving refractory angina, relevant clinical studies are rare and clinical evidence is lacking. Methods and design This is a prospective, parallel-group, randomized controlled trial. We enrolled 200 patients with coronary artery disease who had undergone percutaneous coronary intervention (PCI) and randomized them into two groups. The intervention group will be given usual-practice plus cardiovascular ultrasound therapy intervention and the control group will be given only usual-practice intervention. After 20 treatments with cardiovascular ultrasound therapy, high‐sensitivity C‐reactive protein in serum will be used as the primary outcome measures. The following will be used in determining secondary outcomes: indicators of serum myocardial injury, blood lipid levels, markers of endothelial function, inflammatory factors, hemodynamic indicators, echocardiography, ultrasound examination for carotid plaques, 6-minute walk test, short-term variability in heart rate, and mental health assessment. The researchers plan to test the outcome indicators at multiple time points. Statistical analyses will be performed using SPSS version 26 statistical software (IBM, Armonk, NY). Discussion This is the first clinical study of the rehabilitative efficacy of cardiovascular ultrasound therapy in the treatment of CAD after PCI. Clinical recovery currently depends mainly on modalities such as medication, exercise, and nutritional therapy; therefore, cardiovascular ultrasound therapy, as a new mode of therapy, might become a major advance in the treatment of CAD after PCI. Trial registration ClinicalTrials.gov NCT06640400

Portable muon beam could accelerate archaeology scans