bluuebunny/crossref_metadata_2025 huggingface dataset:
Overburdened Ferroptotic Stress Impairs Tooth Morphogenesis
Authors: Wang H.S. , Wang X.F. , Wang C.L. , Yu F.Y. , Ye L.
Published: August 2023

Regulated cell death (RCD) has been reported to play a critical role in organ development. Despite apoptosis, the best known and most studied RCD in organogenesis, whether newly identified non-apoptotic cell death participates in the physiological process like development is barely understood. As a metabolic-related cell death pathway, ferroptosis, characterized by iron-dependent and lethal lipid peroxidation, was firstly described in 2012 and is now being wildly explored for its pathological function. Main factors of ferroptosis, lipid metabolism, ROS biology, and iron regulation, are also critically involved in developmental progress but hard to manipulate and investigate effectively
in vivo
through a high throughput way. Here in our study, an
ex vivo
culture model of tooth germ is applied to investigate the possible role of ferroptosis in organogenesis, since both RCD and risk factors of ferroptosis (lipid metabolism, ROS biology, and iron regulation) participate in tooth morphogenesis and the well-established
ex vivo
culture model enables effective manipulation of ferroptosis. To investigate whether ferroptotic stress exists and may influence tooth germ development, we detect the spatiotemporal expression of Gpx4, a core anti-lipid peroxidation enzyme in ferroptosis, in mouse development first molar and incisor. Morphological changes in each group with/without activation of ferroptosis are identified by gross anatomy, sequential HE staining, and related 3D reconstruction. Ferroptosis-related genes, lipid peroxidation, the morphology of mitochondria, and iron accumulation are detected to confirm the activation of ferroptosis. Inhibition of ferroptosis by DFO, Fer-1, and Lip-1, could partly rescue organogenesis of erastin-impaired tooth morphogenesis. Moreover, apoptosis is not significantly activated in erastin-impaired tooth germ indicated by cleavage of Caspase-3 and TUNEL staining. These results demonstrate that ferroptotic stress exists in tooth organogenesis but is well controlled by following upregulation of Gpx4; Overburdened ferroptotic stress cause by erastin significantly suppress tooth morphogenesis.
The Alk receptor tyrosine kinase regulates Sparkly, a novel activity regulating neurosecretory protein in the Drosophila CNS
Authors: Sukumar Sanjay Kumar , Antonydhason Vimala , Molander Linnea , Sandakly Jawdat , Umapathy Ganesh , Mendoza-Garcia Patricia , Masudi Tafheem , Schlossser Andreas , Nässel Dick R. , Wegener Christian , Shirinian Margret , Palmer Ruth H.
Published: August 2023

Numerous roles for the Alk receptor tyrosine kinase have been described in
Drosophila
, including functions in the CNS, however the molecular details are poorly understood. To gain mechanistic insight, we employed Targeted DamID (TaDa) transcriptional profiling to identify targets of Alk signaling in the larval CNS. TaDa was employed in larval CNS tissues, while genetically manipulating Alk signaling output. The resulting TaDa data were analysed together with larval CNS scRNA-seq datasets performed under similar conditions, identifying a role for Alk in the transcriptional regulation of neuroendocrine gene expression. Further integration with bulk/scRNA seq and protein datasets from larval brains in which Alk signaling was manipulated, identified a previously uncharacterized
Drosophila
neuropeptide precursor encoded by
CG4577
as an Alk signaling transcriptional target.
CG4577
, which we named
Sparkly (Spar),
is expressed in a subset of Alk-positive neuroendocrine cells in the developing larval CNS, including circadian clock neurons. In agreement with our TaDa analysis, overexpression of the
Drosophila
Alk ligand Jeb resulted in increased levels of Spar protein in the larval CNS. We show that Spar protein is expressed in circadian (Clock) neurons, and
Spar
mutant flies exhibit defects in sleep and circadian rhythm control. In summary, we report a novel activity regulating neuropeptide precursor gene that is regulated by Alk signaling in the
Drosophila
CNS.
Social navigation: distance and grid-like codes support navigation of abstract social space in human brain
Authors: Liang Zilu , Wu Simeng , Wu Jie , Wang Wenxu , Qin Shaozheng , Liu Chao
Published: August 2023

People form impressions about others during daily social encounters and infer personality traits from others’ behaviors. Such trait inference is thought to rely on two universal dimensions, i.e., competence and warmth. These two dimensions can be used to construct a ‘social cognitive map’ organizing massive information obtained from social encounters efficiently. Originated from spatial cognition, the neural codes supporting representation and navigation of spatial cognitive map has been widely studied. Recent studies suggest similar neural mechanism subserves the map-like architecture in social cognition as well. Here we investigated how spatial codes operate beyond physical environment and support the representation and navigation of social cognitive map. We designed a social value space defined by two dimensions of competence and warmth. Behaviorally, participants were able to navigate to a learned location from random starting locations in this abstract social space. At neural level, we identified representation of distance in precuneus, fusiform gyrus and middle occipital gyrus. We also found grid-like representation patterns in medial prefrontal cortex and entorhinal cortex. Moreover, the intensity of grid-like response scaled with performance of navigating in social space and social avoidance trait scores. Our findings suggest a neurocognitive mechanism by which social information can be organized into a structured representation namely cognitive map and its relevance to social well-being.
Lactate transporter MCT1 in hepatic stellate cells promotes fibrotic collagen expression in nonalcoholic steatohepatitis
Authors: Min Kyounghee , Yenilmez Batuhan , Kelly Mark , Echeverria Dimas , Elleby Michael , Lifshitz Lawrence M. , Raymond Naideline , Tsagkaraki Emmanouela , Harney Shauna M. , DiMarzio Chloe , McHugh Nicholas , Bramato Brianna , Morrision Brett , Rothstein Jeffery D. , Khvorova Anastasia , Czech Michael P.
Published: August 2023

Circulating lactate is a fuel source for liver metabolism but may exacerbate metabolic diseases such as nonalcoholic steatohepatitis (NASH). Indeed, haploinsufficiency of lactate transporter monocarboxylate transporter 1 (MCT1) in mice reportedly promotes resistance to hepatic steatosis and inflammation. Here, we used adeno-associated virus (AAV) vectors to deliver thyroxin binding globulin (TBG)-Cre or lecithin-retinol acyltransferase (Lrat)-Cre to MCT1
fl/fl
mice on a choline deficient, high fat NASH diet to deplete hepatocyte or stellate cell MCT1, respectively. Stellate cell MCT1KO (AAV-Lrat-Cre) attenuated liver type 1 collagen protein expression and caused a downward trend in trichrome staining. MCT1 depletion in cultured human LX2 stellate cells also diminished collagen 1 protein expression. Tetra-ethylenglycol-cholesterol (Chol)-conjugated siRNAs, which enter all hepatic cell types, and hepatocyte-selective tri-N-acetyl galactosamine (GN)-conjugated siRNAs were then used to evaluate MCT1 function in a genetically obese NASH mouse model. MCT1 silencing by Chol-siRNA decreased liver collagen 1 levels, while hepatocyte-selective MCT1 depletion by AAV-TBG-Cre or by GN-siRNA unexpectedly increased collagen 1 and total fibrosis without effect on triglyceride accumulation. These findings demonstrate that stellate cell lactate transporter MCT1 significantly contributes to liver fibrosis through increased collagen 1 protein expression
in vitro
and
in vivo
, while hepatocyte MCT1 appears not to be an attractive therapeutic target for NASH.
Integrative analysis of DNA replication origins and ORC-/MCM-binding sites in human cells reveals a lack of overlap
Authors: Tian Mengxue , Wang Zhenjia , Su Zhangli , Shibata Etsuko , Shibata Yoshiyuki , Dutta Anindya , Zang Chongzhi
Published: August 2023

Based on experimentally determined average inter-origin distances of ~100 kb, DNA replication initiates from ~50,000 origins on human chromosomes in each cell cycle. The origins are believed to be specified by binding of factors like the origin recognition complex (ORC) or CTCF or other features like G-quadruplexes. We have performed an integrative analysis of 113 genome-wide human origin profiles (from five different techniques) and five ORC-binding profiles to critically evaluate whether the most reproducible origins are specified by these features. Out of ~7.5 million union origins identified by all datasets, only 0.27% (20,250 shared origins) were reproducibly obtained in at least 20 independent SNS-seq datasets and contained in initiation zones identified by each of three other techniques, suggesting extensive variability in origin usage and identification. Also, 21% of the shared origins overlap with transcriptional promoters, posing a conundrum. Although the shared origins overlap more than union origins with constitutive CTCF-binding sites, G-quadruplex sites, and activating histone marks, these overlaps are comparable or less than that of known transcription start sites, so that these features could be enriched in origins because of the overlap of origins with epigenetically open, promoter-like sequences. Only 6.4% of the 20,250 shared origins were within 1 kb from any of the ~13,000 reproducible ORC-binding sites in human cancer cells, and only 4.5% were within 1 kb of the ~11,000 union MCM2-7-binding sites in contrast to the nearly 100% overlap in the two comparisons in the yeast, Saccharomyces cerevisiae. Thus, in human cancer cell lines, replication origins appear to be specified by highly variable stochastic events dependent on the high epigenetic accessibility around promoters, without extensive overlap between the most reproducible origins and currently known ORC- or MCM-binding sites.
Unsupervised discovery of family specific vocal usage in the Mongolian gerbil
Authors: Peterson Ralph E , Choudhri Aman , Mitelut Catalin , Tanelus Aramis , Capo-Battaglia Athena , Williams Alex H , Schneider David M , Sanes Dan H
Published: August 2023

In nature, animal vocalizations can provide crucial information about identity, including kinship and hierarchy. However, lab-based vocal behavior is typically studied during brief interactions between animals with no prior social relationship, and under environmental conditions with limited ethological relevance. Here, we address this gap by establishing long-term acoustic recordings from Mongolian gerbil families, a core social group that uses an array of sonic and ultrasonic vocalizations. Three separate gerbil families were transferred to an enlarged environment and continuous 20-day audio recordings were obtained. Using a variational autoencoder (VAE) to quantify 583,237 vocalizations, we show that gerbils exhibit a more elaborate vocal repertoire than has been previously reported and that vocal repertoire usage differs significantly by family. By performing gaussian mixture model clustering on the VAE latent space, we show that families preferentially use characteristic sets of vocal clusters and that these usage preferences remain stable over weeks. Furthermore, gerbils displayed family-specific transitions between vocal clusters. Since gerbils live naturally as extended families in complex underground burrows that are adjacent to other families, these results suggest the presence of a vocal dialect which could be exploited by animals to represent kinship. These findings position the Mongolian gerbil as a compelling animal model to study the neural basis of vocal communication and demonstrates the potential for using unsupervised machine learning with uninterrupted acoustic recordings to gain insights into naturalistic animal behavior.
Structural characterization of ligand binding and pH-specific enzymatic activity of mouse Acidic Mammalian Chitinase
Authors: Díaz Roberto Efraín , Ecker Andrew K. , Correy Galen J. , Asthana Pooja , Young Iris D. , Faust Bryan , Thompson Michael C. , Seiple Ian B. , Van Dyken Steven J. , Locksley Richard M. , Fraser James S.
Published: August 2023

Chitin is an abundant biopolymer and pathogen-associated molecular pattern that stimulates a host innate immune response. Mammals express chitin-binding and chitin-degrading proteins to remove chitin from the body. One of these proteins, Acidic Mammalian Chitinase (AMCase), is an enzyme known for its ability to function under acidic conditions in the stomach but is also active in tissues with more neutral pHs, such as the lung. Here, we used a combination of biochemical, structural, and computational modeling approaches to examine how the mouse homolog (mAMCase) can act in both acidic and neutral environments. We measured kinetic properties of mAMCase activity across a broad pH range, quantifying its unusual dual activity optima at pH 2 and 7. We also solved high resolution crystal structures of mAMCase in complex with chitin, where we identified extensive conformational ligand heterogeneity. Leveraging these data, we conducted molecular dynamics simulations that suggest how a key catalytic residue could be protonated via distinct mechanisms in each of the two environmental pH ranges. These results integrate structural, biochemical, and computational approaches to deliver a more complete understanding of the catalytic mechanism governing mAMCase activity at different pH. Engineering proteins with tunable pH optima may provide new opportunities to develop improved enzyme variants, including AMCase, for therapeutic purposes in chitin degradation.
Task-specific invariant representation in auditory cortex
Authors: Heller Charles R. , Hamersky Gregory R. , David Stephen V.
Published: August 2023

Categorical sensory representations are critical for many behaviors, including speech perception. In the auditory system, categorical information is thought to arise hierarchically, becoming increasingly prominent in higher order cortical regions. The neural mechanisms that support this robust and flexible computation remain poorly understood. Here, we studied sound representations in primary and non-primary auditory cortex while animals engaged in a challenging sound discrimination task. Population-level decoding of simultaneously recorded single neurons revealed that task engagement caused categorical sound representations to emerge in non-primary auditory cortex. In primary auditory cortex, task engagement caused a general enhancement of sound decoding that was not specific to task-relevant categories. These findings are consistent with mixed selectivity models of neural disentanglement, in which early sensory regions build an overcomplete representation of the world and allow neurons in downstream brain regions to flexibly and selectively read out behaviorally relevant, categorical information.
How small deviations in kinematics and body form dictate muscle performances in the finely tuned avian downstroke
Authors: Deetjen Marc E. , Chin Diana D. , Heers Ashley M. , Tobalske Bret W. , Lentink David
Published: August 2023

Avian takeoff requires peak pectoralis muscle power to generate sufficient aerodynamic force during the downstroke. Subsequently the much smaller supracoracoideus recovers the wing during the upstroke. How the pectoralis work loop is tuned to power flight is unclear. We integrate wingbeat-resolved muscle, kinematic and aerodynamic recordings
in vivo
with a new mathematical model to disentangle how the pectoralis muscle overcomes wing inertia and generates aerodynamic force during takeoff in doves. Doves reduce the incidence of their wing mid-downstroke to efficiently generate aerodynamic force, resulting in an aerodynamic power dip, that allows transferring excess pectoralis power into tensioning the supracoracoideus tendon to assist the upstroke—improving the pectoralis work loop efficiency simultaneously. Integrating extant bird data, our model shows how the pectoralis of birds with faster wingtip speed need to generate proportionally more power. Finally, birds with disproportionally larger wing inertia need to activate the pectoralis earlier to tune their downstroke.
WRNIP1 prevents transcription-associated genomic instability
Authors: Valenzisi Pasquale , Marabitti Veronica , Pichierri Pietro , Franchitto Annapaola
Published: August 2023

R-loops are non-canonical DNA structures that form during transcription and play diverse roles in various physiological processes. Disruption of R-loop homeostasis can lead to genomic instability and replication impairment, contributing to several human diseases, including cancer. Although the molecular mechanisms that protect cells against such events are not fully understood, recent research has identified the fork protection factors and the DNA damage response proteins as regulators of R-loop dynamics. Here, we identify the Werner helicase-interacting protein 1 (WRNIP1) as a novel factor that counteracts transcription-associated DNA damage upon replication perturbation. Loss of WRNIP1 leads to R-loop accumulation, resulting in collisions between the replisome and transcription machinery. We observe co-localization of WRNIP1 with transcription/replication complexes and R-loops after replication perturbation, suggesting its involvement in resolving transcription-replication conflicts. Moreover, WRNIP1-deficient cells show impaired replication restart from transcription-induced fork stalling. Notably, transcription inhibition and RNase H1 overexpression rescue all the defects caused by loss of WRNIP1. Importantly, our findings highlight the critical role of WRNIP1 ubiquitin-binding zinc finger (UBZ) domain in preventing pathological persistence of R-loops and limiting DNA damage, thereby safeguarding genome integrity.
Chromatin and gene expression changes during female Drosophila germline stem cell development illuminate the biology of highly potent stem cells
Authors: Pang Liang-Yu , DeLuca Steven , Zhu Haolong , Urban John M. , Spradling Allan C.
Published: August 2023

Highly potent animal stem cells either self renew or launch complex differentiation programs, using mechanisms that are only partly understood. Drosophila female germline stem cells (GSC) perpetuate without change over evolutionary time and generate cystoblast daughters that develop into nurse cells and oocytes. Cystoblasts initiate differentiation by generating a transient syncytial state, the germline cyst, and by increasing pericentromeric H3K9me3 modification, actions likely to suppress transposable element activity. Relatively open GSC chromatin is further restricted by Polycomb repression of testis or somatic cell-expressed genes briefly active in early female germ cells. Subsequently, Neijre/CBP and Myc help upregulate growth and reprogram GSC metabolism by altering mitochondrial transmembrane transport, gluconeogenesis and other processes. In all these respects GSC differentiation resembles development of the totipotent zygote. We propose that the totipotent stem cell state was shaped by the need to resist transposon activity over evolutionary time scales.
Postmortem Next-Generation Sequencing in an Autopsy Case with Hypertrophic Cardiomyopathy
Authors: Lee Junghye , Park Chaehyun , Yang Kyung-moo
Published: August 2023

Postmor tem next-generation sequencing (NGS) plays a crucial role in uncovering previously unidentified genetic causes of death. It provides essential findings useful for counseling affected family members and advancing our understanding of genetic diseases. In this report, we present the first documented autopsy case of hypertrophic cardiomyopathy (HCM) in South Korea in which postmortem NGS was used to identify a novel mutation. A 40-year-old male with no relevant medical history experienced sudden death at home. The autopsy revealed cardiac findings consistent with HCM but no other potential causes of sudden death. Through postmortem NGS analysis, a novel pathogenic mutation, c.2833_2834del, in MYBPC3 gene, was discovered; hence, this serves as the first report of this mutation in a Korean population. This finding not only confirms the diagnosis of HCM but also provides a plausible explanation for the sudden death. Given the hereditary nature of HCM, genetic counseling is strongly recommended, especially for the deceased’s nine-year-old son, who has a 50% risk of inheriting the mutation. This case underscores the critical role of postmortem NGS in the field of forensic medicine. The significance of NGS and necessity for integration into autopsy investigations are highlighted.
Development and evaluation of a mobile app-based musculoskeletal exercise program for operating room nurses
Authors: Nam Hwawon , Jun Sangeun
Published: August 2023

Purpose: The aim of this study was to develop a mobile app-based musculoskeletal exercise program (AMSEP) for operating room (OR) nurses and evaluate its effects on self-efficacy, the flexibility of the shoulders, lower back, and legs, and musculoskeletal symptoms and fatigue. Methods: The AMSEP was developed based on the information-motivation-behavioral skill model. In total, 48 OR nurses were recruited at a university hospital in Korea and divided into an experimental group (n=24) and a control group (n=24), matched for career experience in the OR. The experimental group participated in the AMSEP, while the control group received a booklet regarding musculoskeletal exercise. Results: The experimental group showed significant increases in self-efficacy (t = -2.77, p = .008) and flexibility of the right shoulder (t = -4.08, p < .001), left shoulder (t = -3.28, p = .002), lower back (t = -3.75, p < .001), and legs (t = -3.96, p < .001) compared to the control group. Musculoskeletal symptoms (t = 2.75, p = .008), and fatigue (Z = -1.98, p = .048) significantly decreased in the experimental group compared to the control group. Conclusion: Our findings indicate that the AMSEP for OR nurses provided information on the prevention of musculoskeletal disorders and methods of exercise, as well as an opportunity for continued exercise performance through self-management. The AMSEP was easily accessible and effective in increasing self-efficacy and flexibility and reducing musculoskeletal symptoms and fatigue.
Over 20% of marine fishes shifting in the North and Barents Seas, but not in the Norwegian Sea
Authors: Gordó-Vilaseca Cesc , Pecuchet Laurene , Coll Marta , Reiss Henning , Jüterbock Alexander , Costello Mark John
Published: August 2023

Climate warming generally induces poleward range expansions and equatorward range contractions of species’ environmental niches on a global scale. Here, we examined the direction and magnitude of species biomass centroid geographic shifts in relation to temperature and depth for 83 fish species in 9,522 standardised research trawls from the North Sea (1998–2020) to the Norwegian (2000–2020) and Barents Sea (2004–2020). We detected an overall significant northward shift of the marine fish community biomass in the North Sea, and individual species northward shifts in the Barents and North Seas, in 20% and 25% of the species’ biomass centroids in each respective region. We did not detect overall community shifts in the Norwegian Sea, where two species (8%) shifted in each direction (northwards and southwards). Among 9 biological traits, species biogeographic assignation, preferred temperature, age at maturity and maximum depth were significant explanatory variables for species latitudinal shifts in some of the study areas, and Arctic species shifted significantly faster than boreal species in the Barents Sea. Overall, our results suggest a strong influence of other factors, such as biological interactions, in determining several species’ recent geographic shifts.
Synthesis of ZnO Nanoparticle using Lidah Mertua (Sansevieria trifasciata) Extract through Sol-Gel Method and Its Application for Methylene Blue Photodegradation
Authors: Saridewi Nanda , Rustanti Selviana , Zulys Agustino , Nurbayti Siti , Aziz Isalmi , Adawiah Adawiah
Published: August 2023

Methylene blue is widely used in the textile industry and is difficult to degrade naturally because of its heterocyclic aromatic structure. One technique that can be used to degrade methylene blue is through a photocatalytic process using ZnO nanoparticles. This study aims to synthesize ZnO nanoparticles using Lidah mertua extract (Sansevieria trifasciata) as a capping agent by the sol-gel method, and determine the characteristics and stability of ZnO nanoparticles in methylene blue photodegradation. The synthesis of ZnO nanoparticles begins with drying Lidah mertua, grinding it, and then extracting it using distilled water. Furthermore, the extract was reacted with Zn(CH3COO)2.2H2O 0.15 M at pH 8. The extract was characterized using Fourier Transform Infrared (FTIR), and the ZnO nanoparticles were characterized using X-Ray Diffraction (XRD), ultraviolet-visible (UV-Vis) DRS, and Scanning Electron Microscopy (SEM). Lidah mertua extract has OH (hydroxyl), CN, CH, and C=C functional groups. The obtained ZnO nanoparticles have a crystal size of 19.324 nm. The crystalline phase is hexagonal; the morphology is spherical, with a particle size of 79.153 nm and a band gap energy of 3.21 eV. ZnO nanoparticles exhibited a methylene blue decolorization of 98.50% through 43.41% by adsorption and 55.09% by photocatalytic mechanism. ZnO nanoparticles showed good stability for a three-cycle reaction. Copyright © 2023 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0)
Deaths Due to COVID-19 in Patients With Cancer During Different Waves of the Pandemic in the US
Authors: Potter Alexandra L. , Vaddaraju Vedha , Venkateswaran Shivaek , Mansur Arian , Bajaj Simar S. , Kiang Mathew V. , Jena Anupam B. , Yang Chi-Fu Jeffrey
Published: August 2023

Importance

With the ongoing relaxation of guidelines to prevent COVID-19 transmission, particularly in hospital settings, medically vulnerable groups, such as patients with cancer, may experience a disparate burden of COVID-19 mortality compared with the general population.

Objective

To evaluate COVID-19 mortality among US patients with cancer compared with the general US population during different waves of the pandemic.

Design, Setting, and Participants

This cross-sectional study used data from the Center for Disease Control and Prevention’s Wide-Ranging Online Data for Epidemiologic Research database to examine COVID-19 mortality among US patients with cancer and the general population from March 1, 2020, to May 31, 2022. The number of deaths due to COVID-19 during the 2021 to 2022 winter Omicron surge was compared with deaths during the preceding year’s COVID-19 winter surge (when the wild-type SARS-CoV-2 variant was predominant) using mortality ratios. Data were analyzed from July 21 through August 31, 2022.

Exposures

Pandemic wave during which the wild-type variant (December 2020 to February 2021), Delta variant (July 2021 to November 2021), or Omicron variant (December 2021 to February 2022) was predominant.

Main Outcomes and Measures

Number of COVID-19 deaths per month.

Results

The sample included 34 350 patients with cancer (14 498 females [42.2%] and 19 852 males [57.8%]) and 628 156 members of the general public (276 878 females [44.1%] and 351 278 males [55.9%]) who died from COVID-19 when the wild-type (December 2020-February 2021), Delta (July 2021-November 2021), and winter Omicron (December 2021-February 2022) variants were predominant. Among patients with cancer, the greatest number of COVID-19 deaths per month occurred during the winter Omicron period (n = 5958): at the peak of the winter Omicron period, there were 18% more deaths compared with the peak of the wild-type period. In contrast, among the general public, the greatest number of COVID-19 deaths per month occurred during the wild-type period (n = 105 327), and at the peak of the winter Omicron period, there were 21% fewer COVID-19 deaths compared with the peak of the wild-type period. In subgroup analyses by cancer site, COVID-19 mortality increased the most, by 38%, among patients with lymphoma during the winter Omicron period vs the wild-type period.

Conclusions and Relevance

Findings of this cross-sectional study suggest that patients with cancer had a disparate burden of COVID-19 mortality during the winter Omicron wave compared with the general US population. With the emergence of new, immune-evasive SARS-CoV-2 variants, many of which are anticipated to be resistant to monoclonal antibody treatments, strategies to prevent COVID-19 transmission should remain a high priority.
Utopian Geometries: Turning Forms and the (Science) Fictions of Utopian Architecture
Authors: Clear Nic
Published: August 2023

It is possible to give previous artworks by other artists a new lease of life as the prima materia for further artistic endeavour. Architects Clear + Park, based in West Yorkshire, have been doing just this with a sculpture by the renowned artist Barbara Hepworth – not by renovating or relocating it, but in an act of digital appropriation. Having 3D scanned it, they manipulated the point clouds produced, to create new forms, vectors and speculative interventions of their own originality. Nic Clear, a co‐founder of the practice, explains how.
Oxygen Defect‐Rich WO3−x–W3N4 Mott–Schottky Heterojunctions Enabling Bidirectional Catalysis for Sulfur Cathode
Authors: Zhang Dan , Duan Tengfei , Luo Yixin , Liu Sisi , Zhang Wanqi , He Yongqian , Zhu Kai , Huang Li , Yang Yue , Yu Ruizhi , Yang Xiukang , Shu Hongbo , Pei Yong , Wang Xianyou , Chen Manfang
Published: August 2023

The serious shuttle effect and intrinsically sluggish oxidation–reduction reaction kinetics of polysulfides severely hinder the practical commercialization of lithium–sulfur (Li–S) batteries. Herein, oxygen‐defect‐rich WO3−x–W3N4 Mott–Schottky heterojunctions are designed as efficient catalysts. Based on theoretical calculations and comprehensive experimental characterization, WO3−x–W3N4 exhibits a lower free energy change (1.03 eV) and Li2S decomposition energy barrier (0.92 eV) than WO3 and W3N4, which significantly enhances the sulfur reduction reaction (SRR) activity. Furthermore, a relationship between the catalytic activity and the energy gaps in the d and p bands centers (Δd–p) is also established, with the low Δd–p of the heterojunction leading to a lower antibonding state energy, which promotes electron transfer and interfacial redox kinetics. Oxygen vacancies can improve the catalytic effect without affecting adsorption. Hence, the Li–S battery using WO3−x–W3N4@CC/S exhibited outstanding rate and duration performance (913.9 mAh g–1 at 2 C, stable 400 cycles at 1 C). Impressively, the battery achieves a high areal capacity of 5.0 mAh cm−2 under a high sulfur loading of 4.98 mg cm−2.
Dynamical Integration of Antimicrobial, Anti‐Inflammatory, and Pro‐Osteogenic Activities on Polyetheretherketone via a Porous N‐Halamine Polymeric Coating
Authors: Wang Ziming , Tang Youchen , Wang Peng , Cheng Ziying , Chen Fenglei , Lu Yan , Wu Yanfeng , Xie Zhongyu , Wu Dingcai , Cai Zhaopeng , Shen Huiyong
Published: August 2023

Polyetheretherketone (PEEK) has been widely used as orthopedic implants, but the poor antimicrobial and osseointegration properties hinder its advanced clinical applications. Most of the modification strategies are difficult to temporally fulfill initial broad‐spectrum antimicrobial and later pro‐osteogenic requirements for a long‐term success of implantation. N‐halamine is a kind of biofriendly antimicrobial agent, and its functional N─Cl groups could be converted into N─H groups, potentially resulting in new bioactivities. Therefore, it is supposed that N‐halamine might provide a feasible design for the dynamical integration of antimicrobial and pro‐osteogenic abilities. Herein, a new class of surface‐porous PEEK implant with an N‐halamine polymeric coating (sp‐PEEK‐NCl) is constructed by successive pore‐making, polymer grafting, and chlorination. The as‐prepared sp‐PEEK‐NCl exhibits broad‐spectrum antibacterial, antifungal, anti‐inflammatory, and pro‐osteogenic effects. More importantly, with the consumption of oxidative chlorine, the N─Cl groups in sp‐PEEK‐NCl are transformed into N─H groups with enhanced pro‐osteogenic ability, endowing sp‐PEEK‐NCl with dynamically compatible bioactivities for osseointegration in different periods after implantation. Rat implant‐associated osteomyelitis model confirms that sp‐PEEK‐NCl obviously reduces infectious bone destruction and promotes osseointegration in vivo. This work may provide a promising strategy for intelligent integration of bioactivities and valuable insight into the design of orthopedic implants in bone tissue engineering.
Spray‐Coated Inorganic Lead‐Free Double Perovskite Cs2AgBiBr6 Based Large‐Scale Triboelectric Nanogenerator for Enhanced Energy Harvesting
Authors: Wang Mengrou , Zhao Jingda , Xu Yubing , Wang Xin , Onwudiwe Damian Chinedu , Fayemi Omolola Esther , Elemike Elias Emeka , Bae Byung Seong , Zhu Ying , Zhu Zhuoya , Zhao Zhiwei , Li Qing , Lei Wei
Published: August 2023

Low‐cost and efficient large‐scale triboelectric nanogenerator (TENG) is considered as the new scheme for distributed mechanical conversion or renewable energy utilization. An extremely popular all‐inorganic lead‐free double perovskite Cs2AgBiBr6 (CABB) has emerged as extraordinary potential material in triboelectric semiconductors’ substitution, overcoming high‐impedance limitations associated with organic‐polymer‐insulator based materials. In this study, assembled by the certified available positive frictional material CABB, TENG with sandwiched structure of ITO/compact‐TiO2/mesoporous‐TiO2/CABB – the poly‐tetra‐fluoroethylene/Al exhibits appropriate performance on environmental stability and output capacity for which structure can impede charges decay. Fabrication process comparison shows that as an inexpensive large‐scale functional films preparation method, sprayed CABB TENG with brilliant relative dielectric constant and work function difference possess more distinguished output characteristics. This is confirmed by higher open‐circuit voltage of 105 V, larger short‐current density of 2.45 mA m−2 at 0.25 Hz motion parameter, and more abundant output power density of 0.76 W m−2 under 10 Hz. Further study confirms that both higher frequency and larger contact‐area are conducive to total output power, while terminal charging speed is inversely or positively proportional with capacitance or mechanical frequency. Final physical display effect of sprayed CABB TENG lights up at least 53 commercial yellow‐LEDs, holding decent energy conversion ability.
The role of ion‐membrane interactions in fast and selective mono/multivalent ion separation with hierarchical nanochannels
Authors: Zhang Jiayu , Lin Yuqing , Zhang Yiren , Wu Baolong , Cao Xingzhong , Shi Zhenjia , Xu Zhicheng , Ying Jiadi , Jin Yan , She Qianhong , Matsuyama Hideto , Yu Jianguo
Published: August 2023

Precise control over the nanofluid behavior of polyelectrolyte‐based membranes is a primary step toward understanding the structure‐morphology‐property relationships to ultimately determine the mass transfer characteristics. In this study, a high‐performance multistacked polyelectrolyte‐based cation exchange membrane (CEM) with a heterogeneous structure and versatile surface chemistry was developed to achieve selective ion conductance. The self‐assembled CEM can facilitate ion permeation with fluxes of 2.9 mol m−2 h−1 for K+ and 0.22 mol m−2 h−1 for Mg2+, reaching a mono/multivalent ionic selectivity of up to 13, outperforming mono/divalent fractionation when compared with state‐of‐the‐art membranes. Molecular dynamic (MD) simulations illustrated the ionic transport trajectory in hierarchical channels with angstrom‐scale cavities using multilayered CEMs. Both the experimental measurements and theoretical simulations indicated that ionic fractionation was associated with a large disparity in the energy barrier between mono/multivalent cations, which was the primary origin of the differences in the ion dehydration‐rehydration processes in the angstrom‐confinement membrane ion channels.
Auf dem Weg zum Verständnis des Bildungs‐ und OER‐Katalysemechanismus von Hydroxiden durch In situ‐ und Operando‐Techniken
Authors: Chen Zongkun , Fan Qiqi , Zhou Jian , Wang Xingkun , Huang Minghua , Jiang Heqing , Cölfen Helmut
Published: August 2023

Die Entwicklung effizienter und kostengünstiger Elektrokatalysatoren für die träge Sauerstoffentwicklungsreaktion (engl. oxygen evolution reaction, OER), stellt nach wie vor eine große Hürde dar die überwunden werden muss, um die praktische Anwendung der Wasserstoffproduktion mittels Wasserelektrolyse, der Umwandlung von CO2 in chemisch hochwertige Verbindungen sowie in Metall‐Luft‐Batterien zu ermöglichen. In letzter Zeit haben sich Hydroxide als vielversprechende Elektrokatalysatoren für die OER erwiesen. In situ‐ oder Operando‐Techniken sind insbesondere für die Überwachung der zentralen Zwischenprodukte und das Verständnis des Reaktionsprozesses unerlässlich. Dies ist von entscheidender Bedeutung für die Aufklärung des Katalytischemechanismus der Hydroxidbildung und für die Entwicklung kostengünstiger Elektrokatalysatoren für die OER. Es fehlt jedoch eine umfassende Diskussion über den aktuellen Stand und die Herausforderungen bei der Untersuchung dieser Mechanismen mit In situ‐ oder Operando‐Techniken, was uns daran hindert, die in diesem Bereich bestehenden Hindernisse zu erkennen und zu überwinden. Dieses Review gibt einen Überblick über In situ‐ sowie Operando‐Techniken und beschreibt deren Potenziale, Vor‐ und Nachteile. Jüngste Erkenntnisse über den Bildungsmechanismus und den OER‐Katalysemechanismus von Hydroxiden, die durch In situ‐ oder Operando‐Techniken aufgedeckt wurden, werden ebenfalls eingehend erörtert. Darüber hinaus werden einige aktuelle Herausforderungen auf diesem Gebiet aufgezeigt und geeignete Lösungsstrategien vorgestellt.
Sorption of vapors in methanol soaked and in thermally annealed Matrimid® films
Authors: Vopička Ondřej , Dendisová Marcela , Sysel Petr , Hrdlička Zdeněk
Published: August 2023

Matrimid® shows well separated sub‐glass transitions and substantial entrapment of dichloromethane (DCM) in the solution‐cast films. The entrapped DCM was removed by soaking the polymer in the excess of liquid methanol followed either by thermal annealing (vacuum at 200°C) or by the desorption at mild conditions. These physical treatments influenced the sorption kinetics and even the sorption isotherms for vapors of DCM, methanol (MeOH) and acetonitrile (MeCN) at 35.0°C. The sorption isotherms for the thermally annealed Matrimid® were shifted to those for the methanol‐soaked Matrimid® upon its exposure to sufficiently saturated vapors. The physical treatments changed the β sub‐glass transition of the polymer, and did not cause changes in the chemical composition and microstructure as sensed using ATR‐FTIR and SEM, respectively. Relaxation of the annealed Matrimid® was achieved by its soaking in liquid MeOH and by the exposure to vapors, their threshold saturation followed the same order as diffusivity: MeOH > MeCN > DCM. Although methanol appears the least effective agent to induce the relaxation of Matrimid®, it diffuses in and desorbs from the polymer readily. Liquid MeOH and its vapor thus appear the media of choice for causing the relaxation and removal of entrapped solvents from Matrimid®.
Benton Harbor: From Lead Crisis to Lead‐Free
Authors: Betanzo Elin Warn , Pinkney Edward , Land Danielle
Published: August 2023

Key Takeaways

A community effort in Benton Harbor, Mich., drew attention to the lack of public education about lead levels in water and highlighted the need for lead service line replacement.

The state and the US Environmental Protection Agency responded quickly to a community petition to address the lead crisis and involved the community in the response.

In 11 months, 99% of Benton Harbor's service lines had been replaced or confirmed as non‐lead, while residents received information and solutions to ensure they had safe drinking water.
Laboratory Safety Program Fundamentals
Authors: Adams Hunter , Chapman Vanessa , Reyes Dimas , Cottrell Ashley , Schneider Christine , Beier Alejandra
Published: August 2023

Key Takeaways

An effective laboratory safety program focuses on preventing harm by reducing risks to staff and the laboratory itself.

All laboratory safety programs should include documentation and training, safety data sheets, personal protective equipment, emergency shower/eyewash, fire safety, and first aid.

Safety programs should address the specific analysis, such as microbiology or hazardous chemicals present.

Operations laboratories should also have safety programs, even if they only perform process control testing.
Über das b der Van der Waalsschen Gleichung
Authors: Herz W.
Published: August 2023

Die Proportionalität von bk und M : dk wurde untersucht und im großen Ganzen durch das bekannte Tatsachenmaterial bestätigt; einzelne besonders hervortretende Abweichungen wurden zu charakterisieren gesucht. In der Reihe der Edelgase stellt Neon in Bezug auf bk und M : dk eine Unstimmigkeit vor. b0 und M : d0 fallen sehr nahezu zusammen; in homologen Reihen organischer Verbindungen wächst M : d0 etwas stärker als b0 mit steigendem Molekülgewicht.
Recherches sur la surtension d'hydrogène
Authors: Darmois‐Sutra Geneviève , Darmois Eugène
Published: August 2023

Das Wasserstoff‐Ion in wässeriger Lösung wird gewöhnlich (H3O)+ formuliert. In bezug auf dieses Ion haben wir 1946 die Vorstellung entwickelt: das Ion wäre ein Proton, das in einem Käfig aus Wassermolekülen eingeschlossen sei; in diesem Käfig führe das Ion eine thermische Bewegung aus. Wir haben auf diese Bewegung die Theorie von Drude‐Lorentz und die klassische Statistik angewandt. Diese Theorie erklärt

1. die anomale Leitfähigkeit des Ions H+,

2. das Verhältnis der Beweglichkeiten der Ionen H+ und D+,

3. die große Hydratationswärme dieser Ionen.

An einer Kathode sind die H+‐Ionen mit Wassermolekülen adsorbiert; von Zeit zu Zeit entweichen die Protonen ihrer Umgebung; die Bildung des Wasserstoffs findet in der Kathode statt. Auf diesen Prinzipien kann eine Theorie der Wasserstoffüberspannung aufgebaut werden.
Experimentelle Ergebnisse über die Primärreaktionen bei der Kohlenstoffverbrennung
Authors: Rossberg M.
Published: August 2023

Mit graphitisierter, poröser Spektralkohle höchster Reinheit wurden nach der Methode des durchströmten Kohlezylinders Abbrandversuche bei Temperaturen von 520 bis 1420°C und verschiedenen Drucken (26 bis 208 Torr) durchgeführt. Die drei zu erwartenden Gebiete mit verschiedener Temperaturabhängigkeit — chemische Reaktion, Porendiffusion, Gasraum‐ bzw. Grenzschichtdiffusion — konnten deutlich erfaßt werden. Für die chemische Oberflächenreaktion wurde eine Aktivierungsenergie von etwa 50 kcal/mol gemessen. Das [CO]/[CO2]‐Verhältnis ergab sich weitgehend druckunabhängig und lediglich als eine (exponentielle) Temperaturfunktion. CO und CO2 treten beide als Primärprodukte auf, da die CO‐Nachverbrennung und die Boundouard‐Reaktion nachweislich nicht stattfinden. Für die Primärreaktion wird ein Mechanismus vorgeschlagen, dessen geschwindigkeitsbestimmender Schritt in der Dissoziation adsorbierten Sauerstoffs und Umlagerung zu Oberflächenoxyden besteht und der die hier erhaltenen Befunde sowie anderweitige Erfahrungen zu deuten gestattet.
Über die Diffusion von Argon in Kalifeldspäten
Authors: Noddack W. , Zeitler G.
Published: August 2023

Im Temperaturintervall von 500 bis 1000 °C wurde gemessen, welche Argonmengen aus Orthoklas bestimmter Korngröße entweichen. Diese Messungen sollen zur Klärung de Frage dienen, ob bei den radiochemischen Altersbestimmungen nach der Argonmethode eventuell Korrekturen für das in geologischen Zeiten aus den Gesteinen diffundierende Argon anzubringen sind.
Dicke und Aufbau von passivierenden Oxydschichten auf Eisen
Authors: Vetter K. J.
Published: August 2023

Der Zusammenhang zwischen Schichtwachstum, Stromdichte, Ionenleitfähigkeit und Korrosionsgeschwindigkeit wird behandelt. Hieraus folgt eine potentialabhängige stationäre Schichtdicke. Es ergibt sich, daß die Potentialdifferenz an der Phasengrenze Oxyd/Elektrolyt durch das Gleichgewicht O2− + 2H+ ⇋ H2O eingestellt wird. Innerhalb des Oxyds befindet sich ein starkes Feld der Größenordnung 106 Volt/cm, das die Ionen für die Korrosion und den Schichtaufbau durch die Schicht hindurchzieht. Die gute Elektronenleitfähigkeit ermöglicht den Ablauf von Redoxreaktionen. Die Ionenleitfähigkeit folgt einem Exponentialgesetz der Feldstärke. Aus den Konstanten ergibt sich eine Sprungweite der Ionen von etwa 3 AE.

Das Fladepotential ϵF (Aktivierungs‐ und Passivierungspotential) wird nicht als eine thermodynamisch reversible Potentialgröße gedeutet. Für die Schicht wird ein Aufbau Eisen/Fe3O4/Fe2O3/Elektrolyt angenommen. In der Fe3O4‐Schicht läuft die Reaktion Fe + 4Fe2O3 → 3Fe3O4 vollständig irreversibel ab und gibt Veranlassung zur Ausbildung einer konstanten Potentialdifferenz Δϕ = 0,66 Volt im Fe3O4. Dieses ist die lange so problematische Fehlspannung zwischen Theorie und Experiment. Innerhalb der Fe2O3‐Schicht liegt die Potentialdifferenz Δϵ = ϵ — ϵ. Die Korrosionsgeschwindigkeit des Fe3O4 muß in saurer Lösung als sehr groß angenommen werden, so daß das passive Eisen sich nach Abbau der Fe2O3‐Schicht in saurer Lösung spontan aktiviert. Als Ferrioxyd ist γ‐Fe2O3 wahrscheinlich, das mit Fe3O4 lückenlose Mischphasen bildet.
The passivation process in the presence of the XOn−4 inhibitors
Authors: Cartledge G. H.
Published: August 2023

The behavior of several XOn−4 ions and molecules with respect to the corrosion of iron and steel was studied. The results support the view that a competitive adsorption of the effective inhibitors is involved in their action, and that their specificity derives from an internal difference other than precipitating power and ionic charge or configuration. It is proposed that this specificity depends upon a difference in the polarity of the X‐O bonds, such that those particles in which the polarity and the valence of X are high exert an effective electrostatic polarization in the substrate.

It was shown that the film formed on iron in an aerated inhibitor exhibits the Flade potential during activation by addition of an indifferent electrolyte. An electrode process corresponding to the Flade potential is suggested. The passivation process is discussed from the point of view of the relative rates of reduction of protons and oxygen, respectively, and the possible effect of electrostatic polarization upon these rates.

Evidence is presented for considering the XOn−4 particles to differ among themselves in the degree of polarity of the X‐O bonds. It is shown that covalently and ionically bonded structures lead to very different electrostatic fields near the surface on which they are adsorbed, and the field of the polar particles is discussed with respect to its possible relation to inhibition and other phenomena dependent upon the kinetics of charged‐particle transfer at interfaces.
The passivity of iron in chromate solutions I. Structure and composition of the film
Authors: Cohen M. , Beck A. F.
Published: August 2023

A study of the reactions of chromate with iron has been made. The amount of chromium in the passivating film has been measured using radio‐active chromium and by chemical analysis. The surface of the iron after exposure to chromate was examined by auto‐radiography, electron diffraction and electron microscopy. It was concluded that passivity of iron in chromate solutions is caused by the formation of an oxide film about 100 Å thick containing about 25% Cr2O3 and 75% γ‐Fe2O4.