Browse Articles

Author Correction: Miniaturized circularly polarized wearable array antenna for medical device applications

Diagnosis of early nitrogen, phosphorus and potassium deficiency categories in rice based on multimodal integration and knowledge distillation

Multi scale convolutional neural network combining BiLSTM and attention mechanism for bearing fault diagnosis under multiple working conditions

Steganography beyond space-time with chain of multimodal AI

Electromagnetic and heated pulse laser on wave propagation during electrons and holes excitation processes in a rotator semiconductor medium

Abstract This study focuses on intricate interplay between electrons and holes and generating a Hall current and its impact on the coupled behavior of thermal, mechanical, and electronic fields in a semiconductor thermoelastic medium. The model indeed considers the motion of microscopic particles (charge carriers such as electrons and holes) by coupling their behaviour with thermal and elastic fields. The process of optical-elastic-thermal-diffusion (OETD) is taken into account when a material is subjected to rotation, time, high electromagnetic fields, and laser pulses. Significant data on the existence of new and enhanced waves in many technological and geophysical applications can be obtained from wave propagation in a thermos-diffusion elastic material. Photoelastic and photoelectronic deformations are accounted for, especially when hall currents impact the semiconductor due to magnetic field pressure. To solve the non-dimensional coupled equations, Lame’s potential and normal mode analysis were employed to simplify the fundamental equations that describe the system in 2-D. Graphical representations of numerically simulated results using MATHEMATICA software highlight the influence of hall current (magnetic field), laser pulse, rotation and time on the results, with a focus on silicon (Si) material. Finding of the current study is that the effect of electromagnetic field on wave propagation heated by pulsed laser during the excitation processes of electrons and holes in a rotator semiconductor medium.

Epistasis-mediated compensatory evolution in a fitness landscape with adaptational tradeoffs

The evolutionary adaptation of an organism to a stressful environment often comes at the cost of reduced fitness. For example, resistance to antimicrobial drugs frequently reduces growth rate in the drug-free environment. This cost can be compensated without loss in resistance by mutations at secondary sites when the organism evolves again in the stress-free environment. Here, we analytically and numerically study evolution on a simple model fitness landscape to show that compensatory evolution can occur even in the presence of the stress and without the need for mutations at secondary sites. Fitness in the model depends on two phenotypes—the null-fitness defined as the fitness in the absence of stress, and the resistance level to the stress. Mutations universally exhibit antagonistic pleiotropy between the two phenotypes, that is they increase resistance while decreasing the null-fitness. Initial adaptation in this model occurs in a smooth region of the landscape with a rapid accumulation of stress resistance mutations and a concurrent decrease in the null-fitness. This is followed by a second, slower phase exhibiting partial recovery of the null-fitness. The second phase occurs on the rugged part of the landscape and involves the exchange of high-cost resistance mutations for low-cost ones. This process, which we call exchange compensation, is the result of changing epistatic interactions in the genotype as evolution progresses. The model provides general lessons about the tempo and mode of evolution under universal antagonistic pleiotropy with specific implications for drug resistance evolution.

The effect of H2O2 on elongation growth and oxidative stress in maize coleoptile cells treated with auxin and fusicoccin

Bourbon and Mycbp function with Otu to promote Sxl protein expression in the <i>Drosophila</i> female germline

In Drosophila ovaries, germ cells differentiate through several stages of cyst development before entering meiosis. This early differentiation program depends on both the stepwise deployment of specific regulatory mechanisms and on maintenance of germline sexual identity. The study of female sterile mutations that result in formation of germ cell tumors has been invaluable in identifying the mechanisms that control these developmental events. Here, we characterize the germ cell–enriched gene bourbon (bbn), null mutants of which cause the formation of a mixture of agametic ovarioles and cystic germ cell tumors. We performed proteomic analysis and found Bbn forms a complex with Ovarian tumor (Otu), a protein previously linked with regulation of the sex determination factor Sex lethal ( Sxl ), and the Drosophila ortholog of c-Myc binding protein (Mycbp). Loss of Mycbp also results in the formation of cystic germ cell tumors. Bbn promotes the stability of Otu and fosters interactions between Otu and Mycbp. Germ cells from bbn and Mycbp mutants display a loss of Sxl expression specifically in the germline. Transgenic rescue experiments show the bbn sterile phenotype is independent from Sxl splicing defects. Further evidence suggests Otu physically interacts with and promotes Sxl protein stability. This function does not depend on Otu’s deubiquitinase activity. Last, we find the human orthologs of Otu and Mycbp, OTUD4, and MYCBP, also physically interact, suggesting conservation of function. Together these data provide insights into how a conserved complex promotes the germline expression of Sxl protein and the differentiation of Drosophila germ cells.

Author Correction: LIM Homeobox 4 (lhx4) regulates retinal neural differentiation and visual function in zebrafish

Global subnational estimates of migration of scientists reveal large disparities in internal and international flows

Researchers are key contributors to innovation. Their migration results in talent circulation and recombination of ideas. Due to data shortage, little is known about subnational mobility of scientists and the interrelationships between their internal and international migration patterns. We used data on 30+ million Scopus publications of 19+ million authors to infer migration from changes in affiliations. Our publicly shared database of global subnational estimates of migration reveals relevant disparities in the attractiveness of subnational regions. While, at the country level, some countries have acted as a global hub that attracts scholars from throughout the world, at the subnational level, some of their regions have negative net migration rates, with implications for scientific output and regional development, as well as the perpetuation of migration corridors. On average, subnational inequalities in attracting and sending scholars have increased for international but decreased for internal migration. In most countries, there is no single trend such that all subnational regions have been sending or receiving more scholars. Instead, a mix of patterns has been simultaneously at work, on the backdrop of globalization of migration, which is an asymmetric process where specific regions and subpopulations have higher access to international migration. For most subnational regions, when they are attractive for international migrants, they are also attractive for internal migrants, which is not always the case for emigration. Our results have implications for the global circulation of academic talent by adding the dimension of internal migration to “brain drain” and “brain circulation” in international migration.

A CNN-LSTM-attention based seepage pressure prediction method for Earth and rock dams

Unsupervised learning of structural relaxation in supercooled liquids from short-term fluctuations

Unraveling the relationship between structural information and the dynamic properties of supercooled liquids is one of the great challenges of physics. Dynamic heterogeneity, characterized by the propensity of particles, is often used as a proxy for dynamic slowing. Over the years, significant efforts have been made to capture the structural variations linked to dynamic heterogeneity in supercooled liquids. In this work, we present an innovative unsupervised machine learning protocol based on time-lagged canonical correlation analysis or time-lagged autoencoder to autonomously identify a key order parameter (OP) for the amorphous structures of the Kob-Andersen glass former. The OP is constructed by integrating numerous classical structural descriptors and represents the component with the strongest short-term correlation on a timescale thousands of times shorter than the relaxation time. Strikingly, this OP demonstrates a remarkable correlation with the propensity at long times, significantly outperforming traditional unsupervised models and rivaling supervised models. This demonstrates that fluctuations of structural descriptors contain sufficient information about the long-time dynamic heterogeneity. The most important structural features are the density distributions at mid-range. As a consequence, the OP also exhibits excellent transferability in capturing dynamic heterogeneity across a wide temperature range and greatly facilitates the evaluation of descriptor importance, highlighting its potential for broader application to other glassy systems.

Molecular dynamics reveal potential effects of novel VHL variants on VHL-Elongin C binding in ccRCC patients from Eastern India

Implementation of adolescent HIV screening in two urban pediatric emergency departments in the United States

Objectives Routine, opt-out HIV screening of adolescents and youth (AY) is recommended in the United States in all healthcare settings, including emergency departments (EDs), however, data on ED-based HIV screening among AY remains limited. We aimed to describe the implementation and outcomes of a routine HIV AY screening program in two pediatric EDs in Washington, DC. Methods This was a cross-sectional prospective study of an opt-out HIV point-of-care testing (POCT) program of AY aged 13–24 years at a tertiary-based pediatric ED and community-based pediatric ED in Washington DC from March 2009 to February 2019. Descriptive statistics were used to analyze annual program performance by numbers of eligible AY seen, approached, tested, and new HIV identified. One-time ED staff survey collected barriers to HIV screening. Results During the 10-year period, out of 191,107 AY seen in ED, 21.9% (n=41,913) were approached for HIV POCT, of which 58.7% were tested (n=24,599); 23 new HIV infections (0.09% of tested AY) were identified. A higher proportion of AY were approached at the community-based ED compared to the tertiary-based ED (58.5% vs. 11.4%). The tertiary-based ED experienced a decline in AY approached after shifting the task from designated testers to ED staff. Among 179 surveyed ED staff, the most common barriers to HIV POCT included forgetting to offer the test (41.9%), lack of time (33.0%) and discomfort when approaching parents/guardians (15.6%). Conclusions The rate of new HIV diagnoses among screened AY ED patients was &lt;0.1%, however, less than one-quarter of eligible AY were approached for testing. The staff-run HIV POCT model was successful in the lower acuity community-based pediatric ED, while the larger tertiary-based pediatric ED performed well only with the support of dedicated testers. Future studies are necessary to identify the optimal implementation strategy for sustainable ED-based AY HIV screening in the US.

Spin hall effect of light ellipsometry for nanoscale areal surface measurement

Abstract This paper presents a novel method for the measurement of nanometer-scale surfaces. The proposed technique takes advantage of the spin hall effect of light (SHEL), which occurs as a sub-wavelength beam shift due to the spin-orbit interaction of light when it interacts with non-homogeneous optical media. Governed by the conservation of total angular momentum, the SHEL offers a sensitive approach to detecting the variations of optical properties at an interface. “SHEL Ellipsometry” applies weak measurement principles to observe beam shifts, analogous to traditional ellipsometry, which analyzes the polarization states of incident and reflected light. In ellipsometry, a homogeneous sample with surface roughness less than a tenth of the wavelength can be modeled as a thin film characterized by an equivalent thickness and refractive index. By measuring the transverse shifts of the reflected beam and using raster scanning, SHEL Ellipsometry can map the two-dimensional surface roughness distribution, showing significant potential for nanometer-scale surface measurement.

Structural basis of ZP2-targeted female nonhormonal contraception

Monoclonal antibody IE-3 prevents mouse fertilization by binding ZP2, a major component of the oocyte-specific zona pellucida (ZP). We show that an IE-3-derived single-chain variable fragment (scFV) is sufficient for blocking fertilization in vitro and determine the structural basis of IE-3/ZP2 recognition. The high affinity of this interaction depends on induced fit of the epitope, offering insights for nonhormonal contraceptive design without off-target effects.

Retraction: Casticin potentiates TRAIL-induced apoptosis of gastric cancer cells through endoplasmic reticulum stress

Gated recurrent deep learning approaches to revolutionizing English language learning for personalized instruction and effective instruction

DprA recruits ComM to facilitate recombination during natural transformation in Gram-negative bacteria

Natural transformation (NT) represents one of the major modes of horizontal gene transfer in bacterial species. During NT, cells can take up free DNA from the environment and integrate it into their genome by homologous recombination. While NT has been studied for &gt;90 y, the molecular details underlying this recombination remain poorly understood. Recent work has demonstrated that ComM is an NT-specific hexameric helicase that promotes recombinational branch migration in Gram-negative bacteria. How ComM is loaded onto the postsynaptic recombination intermediate during NT, however, remains unclear. Another NT-specific recombination mediator protein that is ubiquitously conserved in both Gram-positive and Gram-negative bacteria is DprA. Here, we uncover that DprA homologs in Gram-negative species contain a C-terminal winged helix domain that is predicted to interact with ComM by AlphaFold. Using Helicobacter pylori and Vibrio cholerae as model systems, we demonstrate that ComM directly interacts with the DprA winged-helix domain, and that this interaction is critical for DprA to recruit ComM to the recombination site to promote branch migration during NT. These results advance our molecular understanding of recombination during this conserved mode of horizontal gene transfer. Furthermore, they demonstrate how structural modeling can help uncover unexpected interactions between well-studied proteins to provide deep mechanistic insight into the molecular coordination required for their activity.

The impact of ischemic reperfusion injury on contralateral kidneys and the determinants of renal prognosis after robot-assisted partial nephrectomy

Robot-assisted laparoscopic partial nephrectomy (RAPN) is a safe and effective option for renal cell carcinoma (RCC). However, clamping of renal artery during RAPN sometimes causes ischemic reperfusion (IR) injury (IRI), which affects renal function at some later time. In the present study, we inserted catheters into the bilateral ureters from before RAPN until 24 hours after and analyzed urine biomarkers of renal injury excreted from both resected and contralateral kidneys to determine and investigated which biomarkers predict the future decline in renal function in patients with RCC and rodent IR model. Twenty-three patients diagnosed with RCC (66.4 ± 10.8 years old, eGFR: 73.6 ± 15.3 mL/min/1.73m2) were enrolled and ureteral catheters were inserted in both ureters. Urinary neutrophil gelatinase-associated lipocalin (NGAL), beta-2-microglobulin (β₂MG), N-acetyl-β-D-glucosaminidase were measured at several time points. Gene expression of injury markers in contralateral kidneys were analyzed in unilateral IR rodents. All the urinary markers were elevated 30 minutes after the clamping and sustained high until 24 hours in resected kidneys. Meanwhile, urinary NGAL and β2MG excreted from contralateral kidneys increased at 6 and 24 hours after the clamping. Warm ischemic time, estimated blood loss, and excised kidney weight were not associated with renal dysfunction; however, only contralateral urinary β2MG at 6 hours was correlated. Ngal and Il-6 mRNA in contralateral kidneys were upregulated in unilateral IR rodents. RAPN-related IRI induces contralateral kidney injury. Contralateral urinary β2MG can become a potent biomarker to predict the onset of kidney injury after RAPN.