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Expression of Concern: Uterine leiomyoma is associated with the risk of developing endometriosis: A nationwide cohort study involving 156,195 women
A Case of Cervical Ectopic Pregnancy after the <i>Dobbs</i> Decision
Repurposing antibacterial drugs identifies ridinilazole and CRS3123 as promising candidates against vancomycin-resistant enterococci
Genomic and enzymatic insights into α-amylase-producing Bacillus spizizenii strains isolated from Isfahan province, Iran
Objective α-Amylases represent a class of industrially critical enzymes widely employed in food processing, animal feed, and biotechnology sectors. While microbial sources, particularly Bacillus species, serve as preferred production platforms due to their efficiency and scalability, there remains a pressing need to discover novel strains with enhanced enzymatic properties from underexplored environments. This study investigated the isolation and characterization of high-performance α-amylase-producing bacteria from diverse ecological niches across Iran, including Golestan, Mazandaran, Gilan, Kurdistan, and Isfahan, with particular emphasis on their potential application in animal feed industries. Methods Strains capable of producing amylase were extracted from environmental samples in Iran, subjected to screening through starch hydrolysis, and subsequently optimized for their enzymatic activity. The chosen strains underwent morphological and genetic characterization, including 16S / rpoB and whole-genome sequencing, followed by the purification of the enzyme and in silico analysis. Results Through systematic screening of sixty bacterial isolates obtained from soil, water, and industrial effluent samples, four promising strains were selected based on their superior productivity indices (PI > 1.8) and enzymatic activity profiles. Among these, strains S1 and S3 (isolated from the Kuhrang water source and Gavkhouni Wetland in Isfahan province, respectively) demonstrated exceptional α-amylase production capabilities (reaching 34,121 U/g under optimal conditions) along with remarkable stability across broad pH (4−9) and temperature (30−80°C) ranges. Comprehensive genomic characterization, including whole-genome sequencing and phylogenetic analysis, identified these isolates as novel variants of Bacillus spizizenii , marking the first report of this species’ α-amylase potential from Iranian ecosystems, specifically originating from Isfahan province. Further analysis revealed a 1980 bp GH13-family α-amylase gene encoding a 62 kDa enzyme with 93.6% sequence similarity to AmyE of B. subtilis , while molecular docking studies demonstrated strong binding affinities (−8.4 kcal/mol) with maltotetraose, supported by critical interactions with catalytic residues. Conclusions The combination of robust enzymatic activity, exceptional environmental tolerance, and confirmed genetic basis positions these B. spizizenii strains as highly promising candidates for industrial enzyme applications. This work not only expands the known diversity of high-performance α-amylase producers but also provides valuable insights into the biotechnological potential of underutilized Bacillus species from unique geographical sources.
How to Save a Life
Plasma sodium levels are related to resting motor threshold in healthy humans
Abstract Electrolyte homeostasis is essential for normal neuronal function and clinically relevant imbalances can provoke neurological symptoms, including seizures. However, whether electrolyte variations within the normal physiological range affect cortical excitability remains unclear. In this exploratory secondary analysis, we examined baseline data from 42 healthy participants enrolled in a previously conducted clinical trial. We found a significant correlation between plasma sodium levels within the normal physiological range (136–143 mmol/L) and resting motor threshold ( r = 0.47, p = 0.002), an indirect index of cortical excitability, suggesting that lower sodium concentrations may be associated with increased cortical excitability. No significant associations were observed for chloride, potassium, phosphate, or calcium. These preliminary findings raise the possibility that subtle interindividual differences in plasma sodium levels are related to variability in corticospinal excitability. Given that this was a non-prespecified, secondary analysis, further controlled studies are warranted to confirm the association and investigate the underlying mechanisms.
Correction: A GAN-Based Approach for enhancing security in satellite based IoT networks using MPI enabled HPC
Cardiovascular Outcomes with Tirzepatide versus Dulaglutide in Type 2 Diabetes
Safety regulations for cloning and a compass that finds true north
Intelligent carbon price prediction system based on improved secondary decomposition and multi-head attention bidirectional long short-term memory (BiLSTM) model
Simulation and symbolic thinking in equations representing change
Learning simulations can enhance conceptual understanding in numerous education contexts, like physics, chemistry, ecology, and more. This conceptual understanding is often expressed symbolically using equations, and students are assessed on their ability to accurately express their ideas using these equations. In the current study, we explore how simulations can facilitate symbolic thinking, and specifically, how the presentation format of a simulation affects symbolic thinking in physics. Sixty-one undergraduate participants were assigned to one of three conditions: Animated Simulation, Textual Simulation and Control. In both simulation conditions, participants completed a set of tasks by manipulating values of key variables and observing changes in situations. These variables were speed, acceleration and time, and they influenced the motion of a ball in one dimension. While the Animated condition used animation of a moving ball to reflect these changes, the Textual condition reflected these changes through a structured text. No simulation was present in the Control condition. Participants then identified the equation which best described the situation. Compared to the Animated and Control conditions, participants in the Textual condition were more likely to identify the correct general form of the equation, where change was expressed through an addition term. These results highlight the importance of Textual simulations for equations describing one dimensional motion in physics.
Contact Precautions for MRSA and Vancomycin-Resistant Enterococcus
How my institution strengthened research despite chronic underfunding
SD-YOLO: a lightweight model for small target defect detection in complex environments of lithium batteries in new energy vehicles
Distribution of pediatric intensive care beds in Brazil: Regional inequalities and implications for equity in the public health system
Background Pediatric Intensive Care Units (PICUs) play a critical role in reducing child mortality, but their distribution across Brazil remains markedly uneven. Understanding how the spatial and technological distribution of PICU beds relates to regional child health indicators is essential for promoting equity within the Unified Health System (SUS). Objective To examine the national distribution of PICU beds in Brazil, identify regional inequality patterns, and explore their association with pediatric mortality to inform equitable health planning. Methods This cross-sectional ecological study analyzed data from the National Register of Health Establishments (CNES) and demographic indicators from the Brazilian Institute of Geography and Statistics (IBGE) , encompassing all 5,570 municipalities and 450 health regions as of July 2023. Variables included the number and type of PICU beds (types I, II, and III), resident population, proportion of individuals under 14 years, and mortality in this age group. A multivariate cluster analysis was applied to group health regions by similarities in bed availability and mortality profiles, using Bayesian and Akaike Information Criteria and the Silhouette coefficient to define cluster quality. Results A total of 6,489 PICU beds were identified in 708 healthcare providers, with 50% allocated to SUS. Most beds were type II (64.7%), followed by type III (18.6%) and type I (16.6%). Six clusters were identified, revealing marked inequalities: regions with higher proportions of type III beds had lower child mortality (16.5 per 100,000), while areas with predominantly type I beds or none had higher mortality (up to 25.0 per 100,000). Notably, 259 health regions (46%) lacked any PICU beds, affecting over 53 million residents. Conclusions The unequal distribution of PICU beds across Brazil reflects structural inequities in access to pediatric critical care. Policies should prioritize regionalized, quality-based allocation, intergovernmental coordination, and integration of health data systems to guide equitable expansion of pediatric intensive care capacity within the SUS.
Cutaneous Sarcoidosis with Annular Plaques
Sensory processing sensitivity and overstimulation in daily life: an experience sampling method study
Abstract Individuals differ in how they perceive and process social and sensory information in their environment, a personality trait known as Sensory Processing Sensitivity (SPS). Approximately 30% of the general population scores high on this trait making them more responsive to both negative and positive environmental influences than individuals lower in SPS. Overstimulation is one of the biggest challenges associated with SPS. Associations between SPS, triggers, and fluctuations of overstimulation in everyday life were examined using an experience sampling method study (during one week with 5 prompts a day) in 139 healthy adults. Results showed that overstimulation increased in the afternoon to early evening and in the presence of others. Furthermore, more sensitive individuals reported higher levels of overstimulation when auditory and visual stimuli were rated as unpleasant, when fatigued, or in a negative mood. Yet, more sensitive individuals reported lower levels of overstimulation with momentary pleasant auditory and visual stimuli, when not fatigued, and in a positive mood at the current moment. Everyone, but particularly individuals high in SPS, may benefit from interventions preventing fatigue, promoting positive mood and the pleasantness of sensory stimuli in their daily environments to reduce feelings of overstimulation.