Search

We study a long standing open problem by Ulam, which is whether the Euclidean ball is the unique body of uniform density which will float in equilibrium in any direction. We answer this problem in the class of origin symmetric n-dimensional convex bodies whose relative density to water is \frac {1}{2}. For n=3, this result is due to Falconer. [ABSTRACT FROM AUTHOR]

Extensive use of quantum chemical calculations has been made to rationally design a molecule whose spin state can be switched reversibly using light of two different wavelengths at room temperature in solution. Spin change is induced by changing the coordination number of a nickel complex. The coordination number in turn is switched using a photochromic ligand that binds in one configuration and dissociates in the other. We demonstrate that successful design relies on a precise geometry fit and delicate electronic tuning. Our designer complex exhibits an extremely high long-term switching stability (more than 20000 cycles) and a high switching efficiency. The high-spin state is extraordinarily stable with a half-life of 400 days at room temperature. Switching between the dia- and paramagnetic state is achieved with visible light (500 and 430 nm). The compound can also be used as a molecular logic gate with light and pH as input and the magnetic state as non-destructive read-out. [ABSTRACT FROM AUTHOR]

An invading pathogen must be held in check by the innate immune system until a specific immune response can be mounted. In the case of Gram-negative bacteria, the principal stimulator is LPS, a component of the outer membrane of the bacteria. In vitro LPS is bound by LBP and transferred to the LPS receptor CD14 on the macrophage surface. Binding to CD14 triggers an inflammatory response which is crucial for keeping an infection under control. In vitro, LBP mediates a response not only to LPS but also to intact Gram-negative bacteria. We show that whole Escherichia coli bacteria are recognised by CD14 on human monocytes, and subsequently may become phagocytosed. Although neither LBP nor CD14 interact with the heat inactivated, intact Gram-positive bacterium Bacillus subtilis both proteins form stable complexes with lipoteichoic acid derived from the bacterial cell wall. A brief exposure of B. subtilis to serum or antibiotics converts them into a form which can be recognised by CD14 in an LBP-dependent manner followed by phagocytosis. In preliminary experiments, it is shown that LBP is essential in vitro for the oxidative burst response of mouse macrophages induced by living Salmonella typhimurium as well as Staphylococcus epidermidis. Our results indicate that, in addition to CD14, LBP is also a pattern recognition element and is required to induce a rapid inflammatory response to Gram-negative as well as to Gram-positive bacteria and to initiate their phagocytosis. [ABSTRACT FROM PUBLISHER]

The immunoregulatory enzyme indoleamine 2,3-dioxygenase (IDO) controls tryptophan metabolism and is induced by pro-inflammatory stimuli. We investigated whether immunostimulatory treatment with granulocyte-macrophage colony-stimulating factor (GM-CSF) influences IDO activity and tryptophan metabolism in sepsis. Thirty-six patients with severe sepsis/septic shock and sepsis-associated immunosuppression (assessed using monocytic human leukocyte antigen-DR (mHLA-DR) expression) were assessed in a controlled trial of GM-CSF or placebo treatment for 8 days. Using tandem mass spectrometry, levels of tryptophan, kynurenine, kynurenic acid, quinolinic acid, 5-hydroxytryptophan, serotonin, and estimated IDO activity were determined in a blinded fashion over a 9-day interval. At baseline, tryptophan and metabolite levels did not differ between the study groups. Although tryptophan levels were unchanged in both groups over the treatment interval (all p>0.8), IDO activity was markedly reduced after GM-CSF treatment (35.4 ± 21.0 vs 21.6 ±9.9 (baseline vs day 9), p = 0.02). IDO activity differed significantly between the 2 groups after therapy ( p = 0.03). Metabolites downstream of IDO (kynurenine, quinolinic acid, kynurenic acid) were all induced in sepsis and declined in the GM-CSF group, but not in controls. Serotonin pathway metabolites remained unchanged in both groups (all p>0.15). Moreover, IDO activity correlated with procalcitonin ( p< 0.0001, r = 0.56) and mHLA-DR levels ( p = 0.005, r = -0.28) in the overall samples group. Thus, GM-CSF therapy is associated with decreased IDO activity and reduced kynurenine pathway catabolites in sepsis. This may be due to an improved antibacterial defence. [ABSTRACT FROM AUTHOR]

Background: Abdominal sepsis due to intestinal leakage of endogenous gut bacteria is a life-threatening condition. In healthy individuals, T lymphocytes have essential functions in balancing the immune response to the commensal gut flora. Aim: To determine how T lymphocytes shape the process of diffuse faecal peritonitis. Methods: In colon ascendens stent peritonitis (CASP), a clinically relevant mouse model of diffuse peritonitis, the kinetics of systemic T cell activation were investigated by assessment of activation markers. CD4+ T cells were then depleted with monoclonal antibodies, and survival, bacterial dissemination and cytokine concentrations were measured. T cell receptor signalling was blocked with tacrolimus. Results: In diffuse peritonitis, CD4+ T cells, both Foxp3- and Foxp3+, became systemically involved within hours and upregulated CTLA-4 and other activation markers. Depletion of the CD4+ T cells enhanced local bacterial clearance from the peritoneal cavity, reduced bacterial dissemination and improved survival. This was accompanied by increased immigration of granulocytes and macrophages into the peritoneum, indicating that CD4+ T cells inhibit the local innate immune response. Blockade of T cell receptor (TCR) signalling by tacrolimus did not influence the survival in this peritonitis model, showing that the inhibitory effects of the CD4+ T lymphocytes were independent of TCR-mediated antigen recognition. Conclusion: In diffuse peritonitis caused by commensal gut bacteria the CD4+ T lymphocytes exert a net negative effect on the local anti-bacterial defence, and thereby contribute to bacterial dissemination and poor outcome. [ABSTRACT FROM AUTHOR]

Background: The aim of the present study was to compare 16 routine clinical and laboratory parameters, acute physiologic and chronic health evaluation (APACHE) and sequential organ failure assessment (SOFA) score for their value in predicting mortality during hospital stay in patients admitted to a general intensive care unit (ICU). Methods: A retrospective observational clinical study was carried out in a 15-bed ICU in a university hospital. Nine hundred and thirty-three consecutive patients with ICU stay > 24 h (36.2% surgical, 29.1% medical and 34.7% trauma) were observed. Blood sampling, patient surveillance and data collection were performed. The primary outcome was mortality in the hospital. We used receiver operating characteristic (ROC) analyses and logistic regression to compare the 16 relevant parameters, APACHE II and SOFA scores. Results: Two hundred and thirty-three out of the 933 patients died (mortality 25.0%). One laboratory parameter, serum osmolality [area under the curve (AUC) 0.732] had a predictive value for mortality which lay between that of APACHE II (AUC 0.784) and SOFA (AUC 0.720) scores. When outcome prediction was restricted to long-term patients (ICU stay > 5 days), serum osmolality (AUC 0.711) performed better than either of the standard scores (APACHE AUC 0.655, SOFA AUC 0.636). Using logistic regression analysis, the association of clinical parameters, age and diagnosis group with mortality was determined. Conclusion: Elevated serum osmolality at ICU admission is associated with an increased mortality risk in critically ill patients. Serum osmolality is cheaper and more rapid to determine than the scoring systems. However, further studies are needed to evaluate the predictive value of serum osmolality in different patient populations. [ABSTRACT FROM AUTHOR]

Copyright of Erwerbs-Obstbau is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Erwerbs-Obstbau is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Erwerbs-Obstbau is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Hydrogen is a promising energy carrier, but its onboard application is limited by the need for compact, low-pressure storage solutions. Solid-state complex metal hydride systems, such as MgB 2 /Mg(BH 4) 2 , offer high storage capacities but suffer from sluggish kinetics and poor reversibility. One avenue for improving reactivity is to introduce metal dopants to alter electronic and atomic properties, but the role of these chemical additives remains poorly understood, particularly for the hydrogenation reaction. In this work, we used density functional theory calculations on model MgB 2 systems to rationalize the potential role of metal dopants in destabilizing B–B bonding within the MgB 2 lattice. We carried out detailed electronic structure analyses for 28 different metal dopant adatoms to identify properties that contribute to a dopant's efficacy. Based on the simulation results, we propose that an intermediate ionic and covalent character of the bonds between adatoms and B atoms is desirable for facilitating charge redistribution, disrupting the B–B bond network, and promoting H 2 dissociation and H atom chemisorption on MgB 2. [ABSTRACT FROM AUTHOR]

We present a method, based on the classical Green-Kubo theory of linear response, to compute the heat conductivity of extended systems, leveraging energy-density, rather than energy-current, fluctuations, thus avoiding the need to devise an analytical expression for the macroscopic energy flux. The implementation of this method requires the evaluation of the long-wavelength and low-frequency limits of a suitably defined correlation function, which we perform using a combination of recently-introduced cepstral-analysis and Bayesian extrapolation techniques. Our methodology is demonstrated against standard current-based Green-Kubo results for liquid argon and water, and solid amorphous Silica, and compared with a recently proposed similar technique, which utilizes mass-density, instead of energy-density, fluctuations. [ABSTRACT FROM AUTHOR]

Background/Aim: This study aimed to investigate the safety and efficacy of deferoxamine (DFO) pretreated feline adipose tissue derived mesenchymal stem cells (fATMSCs) for the treatment of inflammatory disorders. Materials and Methods: fATMSCs were isolated from feline adipose tissue and characterized using flow cytometry for surface marker expression and differentiation assays for adipogenic, osteogenic, and chondrogenic lineages. Different concentrations of DFO were used to evaluate its impact on fATMSC activity. The therapeutic potential of these preconditioned cells was validated using a mouse model of acute lung injury (ALI) by LPS injection. Comprehensive evaluations, including clinical, hematological, and radiological assessments, were conducted before and after intravenous injection of preconditioned cells in three feline subjects. Results: 25 μM DFO pretreatment significantly upregulated immunomodulatory genes (Tgfb, Hgf, and Tsg-6) in fATMSCs. In the mouse ALI model, DFO-pretreated fATMSCs exhibited enhanced anti-inflammatory effects, reducing inflammatory cytokines (Tnfa, Il1b, Il6). Clinical safety assessment in felines showed no immediate adverse effects, structural alterations, or tumorigenesis. Conclusion: Utilizing a mouse model of acute lung injury, we demonstrated the potential of DFO-pretreated fATMSCs as a safe and effective therapeutic approach for inflammatory disorders. [ABSTRACT FROM AUTHOR]

Following the equivalence between logarithmic Sobolev inequalities and hypercontractivity shown by L. Gross, and applying the ideas and methods of the work by Bobkov, Gentil and Ledoux, we would like to establish a new connection between the logarithmic Sobolev inequalities and the hypercontractivity of solutions of dual Hamilton–Jacobi equations. In addition, Poincaré inequality is also recovered by the dual Hamilton–Jacobi equations. [ABSTRACT FROM AUTHOR]

Liposcelis tricolor (Psocoptera: Liposcelididae) is a significant pest affecting stored products globally. However, due to the lack of a detailed genomic reference, the mechanisms of sex determination, stress resistance, and potential control methods for this booklouse remain poorly understood. In this study, the chromosome-level genome of L. tricolor was assembled by employing Illumina, Nanopore, and Hi-C sequencing technologies. The final genome size was determined to be 229.33 Mb, anchored to 9 pseudo-chromosomes. BUSCO analysis showed that 99.2% of complete BUSCOs were identified, suggesting the high completeness of the genome. A total of 91.49 Mb of repetitive sequences, accounting for 38.84% of the total genome, were annotated, and 15,647 protein-coding genes were predicted, with 88.17% functionally annotated. Additionally, we identified 25 typical sex-determining genes based on the genomic data. This high-quality genome assembly provides a crucial foundation for advancing our comprehension of the molecular biology, genetics, and potential control strategies for psocid L. tricolor. [ABSTRACT FROM AUTHOR]

As natural predators of bacteria, tailed bacteriophages can be used in biocontrol applications, including antimicrobial therapy. Also, phage lysis is a detrimental factor in technological processes based on bacterial growth and metabolism. The spectrum of bacteria bacteriophages interact with is known as the host range. Phage science produced a vast amount of host range data. However, there has been no attempt to analyse these data from the viewpoint of modern phage and bacterial taxonomy. Here, we performed a meta-analysis of spotting and plaquing host range data obtained on strains of production host species. The main metric of our study was the host range value calculated as a ratio of lysed strains to the number of tested bacterial strains. We found no boundary between narrow and broad host ranges in tailed phages taken as a whole. Family-level groups of strictly lytic bacteriophages had significantly different median plaquing host range values in the range from 0.18 (Drexlerviridae) to 0.70 (Herelleviridae). In Escherichia coli phages, broad host ranges were associated with decreased efficiency of plating. Bacteriophage morphology, genome size, and the number of tRNA-coding genes in phage genomes did not correlate with host range values. From the perspective of bacterial species, median plaquing host ranges varied from 0.04 in bacteriophages infecting Acinetobacter baumannii to 0.73 in Staphylococcus aureus phages. Taken together, our results imply that taxonomy of bacteriophages and their bacterial hosts can be predictive of intraspecies host ranges. [ABSTRACT FROM AUTHOR]

Epithelial-mesenchymal interactions (EMI) are fundamental mechanisms in regulating development and organogenesis. Here we summarized the signaling mechanisms involved in EMI in the major developmental events during craniofacial morphogenesis, including neural crest cell induction, facial primordial growth as well as fusion processes. Regional specificity/polarity are demonstrated in the expression of most signaling molecules that usually act in a mutually synergistic/antagonistic manner. The underlying mechanisms of pathogenesis due to disrupted EMI was also discussed in this review. [ABSTRACT FROM AUTHOR]

Highlights a study which was conducted to determine if the Halichondria panicea, a marine sponge, harbors bacteria. Introduction to the study; Identification of the materials used in the study; Methodology of the study; Indepth look at the results; Discussion on the findings.

One important feature of the Propionibacterium acnes-induced hypersensitivity to LPS is the enhanced production of TNFα induced in the sensitized mice upon LPS challenge [Katschinski T., Galanos G., Coumbos A., Freudenberg M.A. Gamma interferon mediates Propionibacterium acnes-induced hypersensitivity to lipopolysaccharide in mice. Infect Immun 1992; 60: 1994-2001]. We investigated the role of LPS binding protein (LBP) in the TNFα response of normal and P. acnes-sensitized mice to LPS in LBP+/+ and LBP-/- mice. Treatment of LBP+/+ (BalbC and 129 Sv) mice with P. acnes enhanced their TNFα response to LPS by 75-200-fold compared to the non-treated controls. Unsensitized LBP-/- (129 Sv x BalbC) mice were also stimulated by LPS to produce low amounts of TNFα. These were enhanced by prior P. acnes treatment, however, only by a factor of 4. The characteristic TNFα hyper-response was absent suggesting that the enhanced activity of LPS in sensitized mice is expressed only in the presence of LBP. Evidence for this was obtained by showing that administration of exogenous LBP restored fully the inducibility of the TNFα hyper-response in P. acnes-sensitized LBP-/- mice. Their response to LPS was 1000-fold higher then that of sensitized controls without LBP. A similar LBP treatment of unsensitized LBP-/- mice increased the TNFα response by a factor of only 5. In an analogous experiment, also IFN-γ-sensitized LBP-/- mice exhibited a TNFα overproduction in response to LPS only in the presence of exogenous LBP. [ABSTRACT FROM PUBLISHER]

Recently it has been demonstrated that the CDI4 molecule which is expressed on monocytes and macrophages serves as a receptor for lipopolysaceharide (LPS) bound to LPS-binding protein (LBP) and thus mediates LPS-induced tumour necrosis factor (TNF) production. Here we report that CD14 is found as a soluble (s) molecule in serum. In healthy volunteers sCDI4 levels (mean + s.c.m.) were 3.7±0.05 μg/ml (n=30, 25-50) years of age) as determined by EI.ISA (detection limit 20 ng/ml serum) using two monoclonal antibodies in a sandwich technique. In polytraumatized patients (n=16) significantly decreased level s(1.7±0.3) were detected immediately after the trauma, which increased to 4.9±0.3 μg/ml within the first 6 days post trauma. sCD14 remained elevated during the first 14 days post trauma in patients with the most severe injuries (injury severity score > 45 points), whereas a return to normal levels was observed in patients with an injury score of <45 points. In addition. the levels of the high-density lipoproteins that partially inactivate free endotoxin arc significantly decreased post trauma. No correlation between parameters of inflammation (C3a and neopterin levels, leucocyte counts, amount of band cells), liver function and sCD14 levels was established. Comparable to polytraumatized patients. increased sCD14 serum levels were observed in live patients with burn trauma (burned area > 35%) within the second week post trauma when clinical signs of septicaemia were evident. [ABSTRACT FROM AUTHOR]

The microbial lysis of deep-sea nodules as a possible result of large-scale, deep-sea mining is considered. It is assumed that the Mn (IV) and Fe (III) compounds of the manganese nodules are reduced by the numerous aerobic bacteria at the sediment/water interface as soon as the adjacent nodule area is buried by sedimentation of the disturbed deposits and the organic-rich debris from the blooming surface plankton. Intensive mineralization processes in the resettled sediments cause oxygen depletion. Subsequently, the aerobic (and anaerobic) microorganisms will switch to Mn (IV) and Fe (III) oxides as alternative electron acceptors in order to continue their energy-conserving (ATP synthesis) reactions (anaerobic respiration). The higher the amount of decomposable organic matter, the more intensive are these processes. Consequently, buried manganese nodules may be dissolved, thereby liberating mobile Mn (II), Fe (II) and several trace elements (Ni, Cu, Co and others). This possible hazard and its ecological consequences should be evaluated carefully before deep-sea mining is started on a large scale. [ABSTRACT FROM AUTHOR]

The introduction of modern Machine Learning Potentials (MLPs) has led to a paradigm change in the development of potential energy surfaces for atomistic simulations. By providing efficient access to energies and forces, they allow us to perform large-scale simulations of extended systems, which are not directly accessible by demanding first-principles methods. In these simulations, MLPs can reach the accuracy of electronic structure calculations, provided that they have been properly trained and validated using a suitable set of reference data. Due to their highly flexible functional form, the construction of MLPs has to be done with great care. In this Tutorial, we describe the necessary key steps for training reliable MLPs, from data generation via training to final validation. The procedure, which is illustrated for the example of a high-dimensional neural network potential, is general and applicable to many types of MLPs. [ABSTRACT FROM AUTHOR]

The application of Machine Learning (ML) algorithms in chemical sciences, particularly computational chemistry, is a vastly emerging area of modern research. While many applications of ML techniques have already been in place to use ML based potential energies in various dynamical simulation studies, specific applications are also being successfully tested. In this work, the ML algorithms are tested to calculate the unimolecular dissociation time of benzene–hexachlorobenzene, benzene–trichlorobenzene, and benzene–monochlorobenzene complexes. Three ML algorithms, namely, Decision-Tree-Regression (DTR), Multi-Layer Perceptron, and Support Vector Regression are considered. The algorithms are trained with simulated dissociation times as functions (attributes) of complexes' intramolecular and intermolecular vibrational energies. The simulation data are used for an excitation temperature of 1500 K. Considering that the converged result is obtained with 1500 trajectories, an ML algorithm trained with 700 simulation points provides the same dissociation rate constant within statistical uncertainty as obtained from the converged 1500 trajectory result. The DTR algorithm is also used to predict 1000 K simulation results using 1500 K simulation data. [ABSTRACT FROM AUTHOR]

Tumor associated macrophages (TAMs) are the predominant innate immune cells in the tumor microenvironment (TME). Cytokines induce the differentiation of macrophages into distinct types of TAMs, primarily characterized by two phenotypes: M1-polarized and M2-polarized. Cancer growth is suppressed by M1-polarized macrophages and promoted by M2-polarized macrophages. The regulation of macrophage M1 polarization has emerged as a promising strategy for cancer immunotherapy. Polysaccharides are important bioactive substances found in numerous plants, manifesting a wide range of noteworthy biological actions, such as immunomodulation, anti-tumor effects, antioxidant capabilities, and antiviral functions. In recent years, there has been a significant increase in interest regarding the immunomodulatory and anti-tumor properties of polysaccharides derived from plants. The regulatory impact of polysaccharides on the immune system is mainly associated with the natural immune response, especially with the regulation of macrophages. This review provides a thorough analysis of the regulatory effects and mechanisms of plant polysaccharides on TAMs. Additionally, an analysis of potential opportunities for clinical translation of plant polysaccharides as immune adjuvants is presented. These insights have greatly advanced the research of plant polysaccharides for immunotherapy in tumor-related applications. [ABSTRACT FROM AUTHOR]

Background/Objectives: Rare diseases are a wide and heterogeneous group of multisystem life-threatening or chronically debilitating clinical conditions with reduced life expectancy and a relevant mortality rate in childhood. Some of these disorders have typical neurological symptoms, presenting from birth to adulthood. Dietary patterns and nutritional compounds play key roles in the onset and progression of neurological disorders, and the impact of alimentary needs must be enlightened especially in rare neurological diseases. This work aims to collect the in vitro, in vivo, and clinical evidence on the effects of diet and of nutrient intake on some rare neurological disorders, including some genetic diseases, and rare brain tumors. Herein, those aspects are critically linked to the genetic, biological, biochemical, and pathophysiological hallmarks typical of each disorder. Methods: By searching the major web-based databases (PubMed, Web of Science Core Collection, DynaMed, and Clinicaltrials.gov), we try to sum up and improve our understanding of the emerging role of nutrition as both first-line therapy and risk factors in rare neurological diseases. Results: In line with the increasing number of consensus opinions suggesting that nutrients should receive the same attention as pharmacological treatments, the results of this work pointed out that a standard dietary recommendation in a specific rare disease is often limited by the heterogeneity of occurrent genetic mutations and by the variability of pathophysiological manifestation. Conclusions: In conclusion, we hope that the knowledge gaps identified here may inspire further research for a better evaluation of molecular mechanisms and long-term effects. [ABSTRACT FROM AUTHOR]

Background: To investigate the association between serum osmolality and deteriorating renal function in patients with acute myocardial infarction (AMI). Methods: Three thousand eight hundred eighty-five AMI patients from the Medical Information Mart for Intensive Care IV were enrolled for this study. The primary outcome was deteriorating renal function. Secondary outcomes included the new-onset of acute kidney injury (AKI) and progress of AKI. < 293.2725 mmol/L was defined as low serum osmolality, and ≥ 293.2725 mmol/L as high serum osmolality based on upper quartile. Univariate and multivariate logistic regression models were used to explore the associations between serum osmolality and the development of deteriorating renal function, the new-onset of AKI and progress of AKI among AMI patients. Subgroup analysis was also conducted. Results: One thousand three hundred ninety-three AMI patients developed deteriorating renal function. After adjusting all confounding factors, high serum osmolality was associated with increased risk of deteriorating renal function [odds ratio (OR) = 1.47, 95% confidence interval (CI): 1.22–1.78], new-onset of AKI (OR = 1.31, 95% CI: 1.01–1.69), and progress of AKI risk (OR = 1.26, 95% CI: 1.01–1.59) among AMI patients. In addition, when the stratified analysis was performed for age, AMI type, cardiogenic shock, and estimated glomerular filtration rate (eGFR), high serum osmolality was risk factor for the risk of deteriorating renal function among patients aged 65 years or older, without cardiogenic shock, and with an eGFR ≥ 60 mL/min/1.73m2. Conclusion: Higher serum osmolality increased the risk of deteriorating renal function among AMI patients. [ABSTRACT FROM AUTHOR]

Copyright of Turkish Journal of Obstetrics & Gynecology is the property of Galenos Yayinevi Tic. LTD. STI and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We explore the stability of floating objects at a two-fluid interface through mathematical modeling and experimentation. Our models are based on standard ideas of center of gravity, center of buoyancy, and Archimedes' Principle extended to the two-fluid scenario. We investigate floating shapes with uniform, two-dimensional cross sections and identify analytically and/or computationally a potential energy landscape that helps identify stable and unstable floating orientations. We compare our analyses and computations to experiments on floating objects designed and created through 3D printing. Additionally, the paper includes open problems for further study. [ABSTRACT FROM AUTHOR]

Expanding the application of methanol fuel cells in the energy economy is only feasible when a low-cost or highly CO-tolerant electrocatalyst replaces Pt catalysts to enhance the electrocatalytic properties of Pt. In this study, a PtAu thin film was produced at the liquid-liquid interface through the simple reduction of [Pt(cod)Cl2] and [Au(PPh3)Cl] complexes. The resulting thin film was directly transferred onto a glassy carbon electrode (without the application of Nafion™) and used as an electrocatalyst in the methanol oxidation reaction. Experimental and theoretical results both confirmed that PtAu exhibits lower CO poisoning compared to PtPd or Pt films. The high jf/jb ratio (where jf is the maximum current of the anodic peak in the forward route and jb is the maximum of peak current in the backward route), and theoretically calculated adsorption energies for PtAu thin film showed higher CO tolerance compared to Pt or PtPd thin film electrocatalysts. [ABSTRACT FROM AUTHOR]

SchNetPack is a versatile neural network toolbox that addresses both the requirements of method development and the application of atomistic machine learning. Version 2.0 comes with an improved data pipeline, modules for equivariant neural networks, and a PyTorch implementation of molecular dynamics. An optional integration with PyTorch Lightning and the Hydra configuration framework powers a flexible command-line interface. This makes SchNetPack 2.0 easily extendable with a custom code and ready for complex training tasks, such as the generation of 3D molecular structures. [ABSTRACT FROM AUTHOR]

Topological data analysis based on persistent homology has been applied to the molecular dynamics simulation for the fast ion-conducting phase (α-phase) of AgI to show its effectiveness on the ion migration mechanism analysis. Time-averaged persistence diagrams of α-AgI, which quantitatively record the shape and size of the ring structures in the given atomic configurations, clearly showed the emergence of the four-membered rings formed by two Ag and two I ions at high temperatures. They were identified as common structures during the Ag ion migration. The averaged potential energy change due to the deformation of the four-membered ring during Ag migration agrees well with the activation energy calculated from the conductivity Arrhenius plot. The concerted motion of two Ag ions via the four-membered ring was also successfully extracted from molecular dynamics simulations by our approach, providing new insight into the specific mechanism of the concerted motion. [ABSTRACT FROM AUTHOR]

ReaxFF reactive force fields have been parameterized for the ground and first excited states of azobenzene and its derivatives. In addition, an extended set of ab initio reference data ensures wide applicability, including to azosystems in complex environments. Based on the optimized force fields, nonadiabatic surface hopping simulations produce photoisomerization quantum yields and decay times of azobenzene, both in the gas phase and in n-hexane solution, in reasonable agreement with higher level theory and experiment. The transferability to other azo-compounds is illustrated for different arylazopyrazoles as well as ethylene-bridged azobenzene. Moreover, it has been shown that the model can be easily extended to adsorbates on metal surfaces. The simulation of the ring-opening of cyclobutene triggered by the photoisomerization of azobenzene in a macrocycle highlights the advantages of a reactive force field model. [ABSTRACT FROM AUTHOR]

Despite the deep conservation of the DNA damage response (DDR) pathway, cells in different contexts vary widely in their susceptibility to DNA damage and their propensity to undergo apoptosis as a result of genomic lesions. One of the cell signaling pathways implicated in modulating the DDR is the highly conserved Wnt pathway, which is known to promote resistance to DNA damage caused by ionizing radiation in a variety of human cancers. However, the mechanisms linking Wnt signal transduction to the DDR remain unclear. Here, we use a genetically encoded system in Drosophila to reliably induce consistent levels of DNA damage in vivo, and demonstrate that canonical Wnt signaling in the wing imaginal disc buffers cells against apoptosis in the face of DNA double-strand breaks. We show that Wg, the primary Wnt ligand in Drosophila, activates epidermal growth factor receptor (EGFR) signaling via the ligand-processing protease Rhomboid, which, in turn, modulates the DDR in a Chk2-, p53-, and E2F1-dependent manner. These studies provide mechanistic insight into the modulation of the DDR by the Wnt and EGFR pathways in vivo in a highly proliferative tissue. Furthermore, they reveal how the growth and patterning functions of Wnt signaling are coupled with prosurvival, antiapoptotic activities, thereby facilitating developmental robustness in the face of genomic damage. The Wnt pathway promotes resistance to DNA damage induced by ionizing radiation in several human cancers, but the mechanisms are not fully understood. This study shows that Wnt signaling in the Drosophila wing imaginal disc modulates the DNA damage response through EGFR, protecting cells from apoptosis induced by DNA double-strand breaks. [ABSTRACT FROM AUTHOR]

Interactions between bacterial microbiota and epibenthic species of the dinoflagellate Prorocentrum may define the onset and persistence of benthic harmful algal blooms (bHABs). Chemical ecological interactions within the dinoflagellate phycosphere potentially involve a complex variety of organic molecules, metabolites, and toxins, including undefined bioactive compounds. In this study, the bacterial diversity and core members of the dinoflagellate-associated microbiota were defined from 11 strains of three epibenthic Prorocentrum species, representing three geographically disjunct locations within Mexican coastal waters. Microbiota profiles in stable monoclonal Prorocentrum cultures were obtained by sequencing amplicons of the V3-V4 region of the 16S rRNA gene. Thirteen classes of bacteria were identified among dinoflagellate clones, where Alphaproteobacteria, Gammaproteobacteria, and Bacteroidia were consistently dominant. The bacterial community structure exhibited significantly different grouping by the location of origin of dinoflagellate clones. No significant diversity difference was found among free-living or unattached bacteria in the dinoflagellate culture medium (M) compared with those in closer association with the dinoflagellate host cells (H). Twelve taxa were defined as core members of the bacterial assemblage, representing the genera Algiphilus, Cohaesibacter, Labrenzia, Mameliella, Marinobacter, Marivita, Massilia, Muricauda, Roseitalea, and an unclassified member of the Rhodobacteraceae. The core members are inferred to significantly contribute to primary and secondary metabolic functions, but no direct correlation with dinoflagellate toxigenicity was apparent. Overall the bacterial profile and implied gene functionality indicated a suite of positive interactions, suggesting either mutualism or commensalism with the dinoflagellate. The further characterization and interpretation of specific gene functions and interactions between bacteria and dinoflagellates, such as epibenthic members of genus Prorocentrum, are key to understanding their role in toxigenesis and bHAB development. [ABSTRACT FROM AUTHOR]

Ceramides are signals of fatty acid excess that accumulate when a cell's energetic needs have been met and its nutrient storage has reached capacity. As these sphingolipids accrue, they alter the metabolism and survival of cells throughout the body including in the heart, liver, blood vessels, skeletal muscle, brain, and kidney. These ceramide actions elicit the tissue dysfunction that underlies cardiometabolic diseases such as diabetes, coronary artery disease, metabolic-associated steatohepatitis, and heart failure. Here, we review the biosynthesis and degradation pathways that maintain ceramide levels in normal physiology and discuss how the loss of ceramide homeostasis drives cardiometabolic pathologies. We highlight signaling nodes that sense small changes in ceramides and in turn reprogram cellular metabolism and stimulate apoptosis. Finally, we evaluate the emerging therapeutic utility of these unique lipids as biomarkers that forecast disease risk and as targets of ceramide-lowering interventions that ameliorate disease. [ABSTRACT FROM AUTHOR]

We consider the problem of producing a ruled Möbius band by subjecting an unstretchable, homogeneous, isotropic, elastic material surface material surface in a circular helicoidal reference configuration to a deformation that is isometric and chirality preserving. We find that such a Möbius band is completely determined by the unit binormal of the Frenet frame of its midline, which must be a geodesic and must have uniform torsion inversely proportional to the pitch of the helicoidal reference configuration. Granted that the energy density of the material surface depends quadratically on the mean curvature of its deformed configuration, we show that the total energy stored in producing a ruled Möbius band as described reduces, in closed form and without approximation, to an integral over the midline of the Möbius band. We formulate and numerically solve a constrained variational problem for finding relative minima of the dimensionally reduced bending energy and construct corresponding stable Möbius bands. The only input parameter entering our variational problem is the number ν of turns in a helicoidal reference configuration. We only find solutions if ν exceeds a certain threshold, which we compute to machine precision. Above that threshold, an interplay between the operative constraints leads to a multiplicity of coexisting stable solutions with n ≥ 3 half twists. For each n ≥ 3 , we construct an energetically optimal Möbius band which exhibits n -fold rotational symmetry. All other energy minima yield Möbius bands which lack symmetry. To our knowledge, this study contains the first examples of stable Möbius bands produced by isometrically deforming reference configurations that are not flat. [ABSTRACT FROM AUTHOR]

Microfluidic tools enable to investigate and manipulate various chemical and biological processes at small scales. As a result, it finds widespread applications in lab‐on‐chip devices, drug delivery systems, or miniaturized cell cultures. However, microfluidic devices are still limited in their flexibility and are often designed to fulfill a single functionality. Moreover, technologies to introduce dynamic functionalities with high precision and at high resolution after the development of a continuous phase microfluidic chip remain scarce. Herein, two‐photon polymerization direct laser writing is introduced as a suitable approach to equip continuous phase microfluidic chips with structurally defined thermoresponsive poly(N‐isopropyl‐acrylamide) (pNIPAM) microactuators. Harnessing the lower critical phase transition temperature of pNIPAM, and upon controlling specific design parameters, the efficient catch and release of polystyrene beads of different sizes using a pNIPAM micropillar brush array is demonstrated. Moreover, a biocompatible pNIPAM microgripper array is designed to subsequently capture and release differently sized (single) cell populations. Overall, the method offers great flexibility and a high degree of freedom toward the fabrication of dynamic microfluidic devices with great adaptability to experimental conditions in real time. [ABSTRACT FROM AUTHOR]

Drosophila models of neurological disease contribute tremendously to research progress due to the high conservation of human disease genes, the powerful and sophisticated genetic toolkit, and the rapid generation time. Fragile X syndrome (FXS) is the most prevalent heritable cause of intellectual disability and autism spectrum disorders, and the Drosophila FXS disease model has been critical for the genetic screening discovery of new intercellular secretion mechanisms. Here, we focus on the roles of three major signaling pathways: BMP, Wnt, and insulin-like peptides. We present Drosophila FXS model defects compared to mouse models in stem cells/embryos, the glutamatergic neuromuscular junction (NMJ) synapse model, and the developing adult brain. All three of these secreted signaling pathways are strikingly altered in FXS disease models, giving new mechanistic insights into impaired cellular outcomes and neurological phenotypes. Drosophila provides a powerful genetic screening platform to expand understanding of these secretory mechanisms and to test cellular roles in both peripheral and central nervous systems. The studies demonstrate the importance of exploring broad genetic interactions and unexpected regulatory mechanisms. We discuss a number of research avenues to pursue BMP, Wnt, and insulin signaling in future FXS investigations and the development of potential therapeutics. [ABSTRACT FROM AUTHOR]

The accurate identification of infections is critical for effective treatment in intensive care units (ICUs), yet current diagnostic methods face limitations in sensitivity and specificity, alongside cost and accessibility issues. Consequently, there is a pressing need for a marker that is economically feasible, rapid, and reliable. Presepsin (PSP), also known as soluble CD14 subtype (sCD14-ST), has emerged as a promising biomarker for early sepsis diagnosis. PSP, derived from soluble CD14, reflects the activation of monocytes/macrophages in response to bacterial infections. It has shown potential as a marker of cellular immune response activation against pathogens, with plasma concentrations increasing during bacterial infections and decreasing post-antibiotic treatment. Unlike traditional markers such as procalcitonin (PCT) and C-reactive protein (CRP), PSP specifically indicates monocyte/macrophage activation. Limited studies in critical illness have explored PSP's role in sepsis, and its diagnostic accuracy varies with threshold values, impacting sensitivity and specificity. Recent meta-analyses suggest PSP's diagnostic potential for sepsis, yet its standalone effectiveness in ICU infection management remains uncertain. This review provides a comprehensive overview of PSP's utility in ICU settings, including its diagnostic accuracy, prognostic value, therapeutic implications, challenges, and future directions. [ABSTRACT FROM AUTHOR]

Introduction: The role of lipopolysaccharide binding protein (LBP), an inflammation marker of bacterial translocation from the gastrointestinal tract, in Alzheimer's disease (AD) is not clearly understood. Methods: In this study the concentrations of LBP were measured in n = 79 individuals: 20 apolipoprotein E (APOE)3/E3 carriers with and 20 without AD dementia, and 19 APOE3/E4 carriers with and 20 without AD dementia. LBP was found to be enriched in the 1.21-1.25 g/mL density fraction of plasma, which has previously been shown to be enriched in intestinally derived high-density lipoproteins (HDL). LBP concentrations were measured by ELISA. Results: LBP was significantly increased within the 1.21-1.25 g/mL density fraction of plasma in APOE3/E3 AD patients compared to controls, but not APOE3/E4 patients. LBP was positively correlated with Clinical Dementia Rating (CDR) and exhibited an inverse relationship with Verbal Memory Score (VMS). Discussion: These results underscore the potential contribution of gut permeability to bacterial toxins, measured as LBP, as an inflammatory mediator in the development of AD, particularly in individuals with the APOE3/E3 genotype, who are genetically at 4-12-fold lower risk of AD than individuals who express APOE4. [ABSTRACT FROM AUTHOR]

(1) The early assessment of wood quality, even while trees are standing, provides significant benefits for forest management, sales efficiency, and market diversification. Its definition cannot be in absolute terms but must always be linked to the material's intended use. (2) In this contribution, a review of the scientific literature is given to discuss the visually evaluable attributes that define wood quality in standing trees, the applicability of the techniques used for their assessment, and the effectiveness of these attributes and technologies in predicting quality, to finally highlight future research needs. (3) The visual characteristics generally used to evaluate wood quality are linked to stem form and dimension, branchiness, and stem damage, but their assessment is challenging due to time and resource constraints. To address these challenges, laser-based and image-based techniques have been applied in field surveys. (4) Laser scanners offer detailed and accurate measurements. Photogrammetry, utilizing images to reconstruct 3D models, provides a cost-effective and user-friendly alternative. Studies have demonstrated the effectiveness of these tools in surveying the visible properties of stems and branches, but further development is necessary for widespread application, particularly in software development, with faster and more effective algorithmic advancements for automatic recognition and subsequent measurement of pertinent characteristics being critical for enhancing tool usability. (5) However, predicting wood quality from these surveys remains challenging, with a limited correlation between the visible tree characteristics assessed and the sawn product quality. Empirical studies evaluating products downstream in the forest-wood supply chain could provide valuable insights. In this sense, the implementation of traceability systems could facilitate the linkage between data on standing trees and the quality of the sawn product. Also, further research is needed to develop models that can accurately predict internal tree characteristics and their impact on product quality. [ABSTRACT FROM AUTHOR]