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Skillful seasonal predictions of continental East-Asian summer rainfall by integrating its spatio-temporal evolution

Efficient sex hormone biosensors in Saccharomyces cerevisiae cells to evaluate human aromatase activity and inhibition

Unconventional hexagonal open Prussian blue analog structures

Determining optimum assembly zone for modular reconfigurable robots using multi-objective genetic algorithm

AbstractReconfigurable modular robots can be used in application domains such as exploration, logistics, and outer space. The robots should be able to assemble and work as a single entity to perform a task that requires high throughput. Selecting an optimum assembly position with minimum distance traveled by robots in an obstacle surrounding the environment is challenging. Therefore, this paper proposes a novel approach for optimizing the assembly zone of modular robots in heterogeneous obstacle environments. The method uses a multi-objective Genetic Algorithm (GA) to minimize total travel distance and individual distance disparities. Utilizing the A* algorithm for path planning ensures efficient navigation. A generic kinematic model enabling holonomic locomotion with any reconfiguration and a new modular robot design are also introduced. Hardware experiments have been conducted to validate the kinematic model’s applicability for holonomic navigation across different robot configurations. Simulations and physical experiments demonstrated the effectiveness of the proposed method in determining assembly zones, with GA outperforming multi-objective pattern search and random selection in terms of total distance and individual distances traveled by the robots.

Copper-catalyzed intermolecular Regio- and Enantioselective Hydrosilylation of Alkenes with Prochiral Silanes

Pharmacological properties of biomimetic synthesized silver nanoparticles from endophytic fungus Coniothyrium chaingmaiense: KUMBMDBT-25

Multiscale X-ray scattering elucidates activation and deactivation of oxide-derived copper electrocatalysts for CO2 reduction

Explainable artificial intelligence with UNet based segmentation and Bayesian machine learning for classification of brain tumors using MRI images

Structural basis of human VANGL-PRICKLE interaction

Ultrasonographic accuracy in evaluating response of clipped lymph nodes in targeted axillary dissection in breast cancer

Author Correction: Multi-method evaluation of a 2-(1,3,4-thiadiazole-2-yl)pyrrolidine corrosion inhibitor for mild steel in HCl: combining gravimetric, electrochemical, and DFT approaches

Age and sex differences in the relationship of body weight changes with colon cancer risks: A nationwide cohort study

Validity and reliability of the brief form of the normative male alexithymia scale among Chinese patients after radical prostatectomy

Collision detection method for anchor digging machine water drilling rig

Abstract Loading water drilling rig on the anchor digging machine can effectively increase the tunneling efficiency. In order to avoid the interference between the water drilling rig and the anchor machine in the working process, it is necessary to calculate the joint variables of the drilling rig accurately. Using the robot kinematics analysis method, the kinematics model of the system is established. At the same time, combined with bounding box collision detection technology, the key parts of the equipment are mathematically modeled. A method for collision detection of onboard water exploration and drainage drilling rig of anchor digging machine is proposed. The simulation results show : The designed collision detection method can be used to guide the attitude adjustment of the equipment during the drilling operation of the equipment, and can accurately analyze the interference characteristics and collision detection of the equipment. It provides a theoretical basis for the automatic excavation of the research object and the automatic control of drilling. The azimuth adjustment range of the water drilling rig for the experiment is : ± 15°, and the pitch angle adjustment range is : + 5° to -10°.

Development of the membrane ceiling method for in vitro spermatogenesis

AbstractSpermatogenesis is one of the most complex processes of cell differentiation and its failure is a major cause of male infertility. Therefore, a proper model that recapitulates spermatogenesis in vitro has been long sought out for basic and clinical research. Testis organ culture using the gas-liquid interphase method has been shown to support spermatogenesis in mice and rats. However, the conventional method using agarose gel has limitations including medium replacement efficiency and live imaging because agarose absorbs medium and is not transparent. To overcome this issue, we developed a new device using microporous membranes and oxygen-permeable materials. Mouse testes sandwiched between a microporous polyethylene terephthalate (PET) membrane on top and an oxygen-permeable 4-polymethyl-1-pentene polymer (PMP) membrane base maintained spermatogenesis over months. The chamber volume was minimized to 0.1% of the culture medium. Weekly time-lapse live imaging enabled us to observe transgenically fluorescent acrosome and nuclear shape formation throughout spermatogenesis. Finally, we obtained healthy fertile offspring from spermatozoa generated in our system. The device could be used not only for basic research to understand spermatogenesis but also for applied research, such as diagnosing and treating male infertility.

Quantitative expression of estrogen, progesterone and human epidermal growth factor receptor-2 and their correlation with immunohistochemistry in breast cancer at Uganda Cancer Institute

The detection of Estrogen Receptor (ER), Progesterone Receptor (PR), and Human epidermal growth factor receptor 2 (HER-2) is important for the stratification of breast cancer and the selection of therapeutic modalities. This study aimed to determine the quantitative expression of ER, PR and HER-2 using Immunohistochemistry and their correlation with quantitative baseline Ct values measured using Quantitative Polymerase Chain Reaction (PCR). This study also assessed the use of fresh breast tissue biopsies preserved in RNAlater solution in the quantitative detection of these receptors using PCR technique. The study evaluated 20 matched formalin fixed paraffin embedded and RNAlater preserved samples for ER, PR, and HER-2 using IHC and quantitative PCR technique. One portion of the breast tissue biopsy was fixed immediately in 10% neutral buffered formalin and another was preserved in RNAlater. After the histological confirmation of breast cancer by the H&E technique, formalin fixed paraffin embedded tissues (FFPE)—positive cases were matched with their corresponding RNAlater samples for IHC and qPCR. The extracted RNA was quantified using Nanodrop technology, resulting into complementary DNA. ER and PR using IHC were expressed in 60% (n = 12) of the study samples and were negative in 40% (n = 8) of samples. HER-2 was negative in 70% (n = 14) of study samples, 25% (n = 5) positive, and 5% (n = 1) equivocal. With the quantitative expression of ER, PR, and HER-2 being reported in the IHC triple—negative breast cancer cases. The mean Ct values for the hormonal receptors correlated with what has been previously studied with ER at 19.631, PR at 25.410 and HER-2 at 25.695. There was no statistically significant difference between the mean Ct values of RNAlater and FFPE with their P-values being 0.9919, 0.0896 and < 0.0001 for ER, PR, and HER-2 respectively. P-values; 0.9919 and 0.0896 for ER and PR respectively being greater than 0.05 it’s a borderline significance although HER-2 had a statistical significance. With a concordance in the detection of these breast cancer hormonal receptors, qPCR can be used in our setting considering the delays that may be associated in following the samples through IHC processing.

Whole genome sequences of nine Taylorella equigenitalis strains isolated in the Czech Republic between 1982–2021: Molecular dating suggests a common ancestor at the time of Roman Empire

Taylorella equigenitalis is the causative agent of sexually transmitted contagious equine metritis. Infections manifest as cervicitis, vaginitis and endometritis and cause temporary infertility and miscarriages of mares. While previous studies have analyzed this organism for various parameters, the evolutionary dynamics of this pathogen, including the emergence of antibiotic resistance, remains unresolved. The aim of this study was to isolate contemporary strains, determine their genome sequences, evaluate their antibiotic resistance and compare them with other strains. We determined nine complete whole genome sequences of T. equigenitalis strains, mainly from samples collected from Kladruber horses in the Czech Republic. While T. equigenitalis strains from Kladruby isolated between 1982 and 2018 were inhibited by streptomycin, contemporary strains were found to be resistant to streptomycin, suggesting the recent emergence of this mutation. In addition, we used the collection dates of Kladruber horse strains to estimate the genome substitution rate, which resulted in a scaled mean evolutionary rate of 6.9×10−7 substitutions per site per year. Analysis with other available T. equigenitalis genome sequences (n = 18) revealed similarity of the Czech T. equigenitalis genomes with the Austrian T. equigenitalis genome, and molecular dating suggested a common ancestor of all analyzed T. equigenitalis strains from 1.5–2.6 thousand years ago, dating to the first centuries A.D. Our study revealed a recently emerged streptomycin resistance in T. equigenitalis strains from Kladruber horses, emphasizing the need for antibiotic surveillance and alternative treatments. Additionally, our findings provided insights into the pathogen’s evolution rate, which is important for understanding its evolution and preparing preventive strategies.

Factors affecting behaviors during complementary feeding in infants and children aged 6–24 months

The process that begins around the 6th month of life and continues until the 24th month is called the complementary feeding period. During this period, infants and children start receiving foods that complement breast milk or formula for the first time. The psychosocial factors the infants and children encounter during this period may affect their growth and health in later life. This cross-sectional and descriptive study aimed to examine the factors influencing behaviors of infants and children during complementary feeding. The study sample included 345 mothers with infants and children aged 6–24 months. The research data were collected using two forms and one scale. The first form contained questions about the mothers’ sociodemographic characteristics, sources of support in childcare, and information sources related to complementary feeding. The second form contained questions about the sociodemographic characteristics of infants and children, the presence of allergies, breastfeeding, and feeding status. The scale used was the validated Behaviors of Transition to Complementary Feeding Scale. The effect of independent variables on behavior of infants and children during complementary feeding was examined using multiple linear regression analysis. Infants/children older than 12 months exhibited more negative behaviors during complementary feeding compared with those aged 6–12 months. The study also found that being the first infant/child in the family had a negative impact on behaviors during complementary feeding. Infants and children currently receiving only complementary feeding displayed more positive behaviors during the complementary feeding process. Paternal support in childcare positively influenced behaviors during this period. In conclusion, complementary feeding is a multifaceted process influenced by various factors, including the infant’s and child’s age, family dynamics, and parental support. Strategies to support mothers, involve fathers, and provide reliable information can facilitate a smoother process of complementary feeding and promote healthier feeding behaviors in infants and children. Descriptive, interventional, qualitative, and mixed-methods studies are required to analyze these factors in detail and improve the complementary feeding process.

Finite element analysis of the plantar support for the medial longitudinal arch with flexible flatfoot

Purpose The present study is to explore the appropriate plantar support force for its effect on improving the collapse of the medial longitudinal arch with flexible flatfoot. Methods A finite element model with the plantar fascia attenuation was constructed simulating as flexible flatfoot. The appropriate plantar support force was evaluated. The equivalent stress of the articular surface of the joints in the medial longitudinal arch and the maximum principal stress of the ligaments around the ankle were obtained. Results The height fall is smaller when applying 15% of body-weight-bearing force as the plantar support for the medial longitudinal arch compared with 10% of the body-weight-bearing while 20% of body-weight-bearing force is over plantar support. The equivalent stress on the articular surface of each joint is smallest when applying 15% of body-weight-bearing force compared with 10% or 20% of the body-weight-bearing force. The maximum principal stress of the anterior talofibular ligament is decreased while other ligaments increased when the plantar fascia attenuation under loading. The maximum principal stress of the tibiocalcaneal ligament and the posterior tibiotalar ligament are decreasing while other ligaments increased with the force increasing gradually. Conclusions Applying 15% of body-weight-bearing to the sole of the foot can restore the height fall of the medial longitudinal arch, and relieve the equivalent articular stress of the talonavicular joint and the talocalcaneal joint as well as the tension stress of the tibiocalcaneal ligament and the posterior tibiotalar ligament.

Relationship between middle school students’ academic stress and physical exercise behavior from the perspective of Self-Determination Theory: The chained mediation of motivation and intention

Academic stress is associated with lower engagement in healthy behaviors, including physical exercise, among middle school students. Based on Self-Determination Theory, this study examines the association between academic stress and physical exercise behavior among middle school students, exploring the mechanisms through the chained mediation of motivation and intention. Scales used in this study include the Academic Stress Scale, Autonomous and Controlled Motivation Scales, and Physical Exercise Intention and Behavior Scales to measure relevant variables. This cross-sectional study involve 290 middle school students (116 males, age = 13.76±0.96 years, grades 7–9) selected from a middle school in Xiamen, China. Structural equation modeling is used to analyze the data, revealing the following results: (1) Academic stress is significantly associated with middle school students’ exercise behavior through the mediating role of exercise intention; (2) Controlled motivation, autonomous motivation, and exercise intention serve as chained mediators between academic stress and exercise behavior; (3) Academic stress is not associated with exercise intention through the parallel mediation of controlled and autonomous motivations. These findings provide new insights into the relationship between academic stress and physical exercise behavior in middle school students.