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Research on multi-condition optimization of centrifugal compressor impeller meridian profile

The turbocharger, a pivotal technology for energy conservation and emission reduction, offers substantial academic significance, particularly in the in-depth study of its core component: the centrifugal compressor impeller. This research aims to enhance the centrifugal compressor’s overall efficiency by optimizing its impeller meridional profile. By modifying the impeller meridional profile of a certain centrifugal compressor impeller to address the issue of discontinuous curvature, this paper aims to optimize the comprehensive average efficiency under variable speed and variable flow conditions. The optimization goal is to improve the overall average efficiency while maintaining the high pressure ratio based on the prototype scheme. The NSGA-III optimization algorithm is employed for multi-condition optimization, aiming to achieve comprehensive efficiency improvements under multiple operating speeds. The following conclusions are drawn: under multi-speed conditions, the optimized scheme exhibits comprehensive efficiency improvements over the prototype scheme, with an expanded stable operating flow range and maintained high-pressure ratio based on efficiency improvement, without sacrificing the operating flow range. Comparisons of internal flow conditions indicate that the optimized impeller features a smoother meridional passage and a reduced high-entropy region at the outlet, leading to lower entropy values. Additionally, pressure increases on both sides of the impeller blades while pressure differentials diminish, signifying enhanced internal flow conditions.

Wind power data cleaning using RANSAC-based polynomial and linear regression with adaptive threshold

A 5,000-fold increase in the HAT reactivity of a nonheme Fe ^IV =O complex simply by replacing two pyridines of the pentadentate N4Py ligand with pyrazoles

A pentadentate [N5] ligand (N2Py2Pz) based on the classic N4Py ( N,N -bis(2-pyridylmethyl)- N -bis(2-pyridyl)methylamine) framework has been synthesized by replacing the two pyridylmethyl arms with corresponding ( N -methyl)pyrazolylmethyl units to form [ N- bis(1-methyl-2-pyrazolyl)methyl- N -( bis -2-pyridylmethyl)amine] (L1). The oxidation of the iron(II) precursor (N2Py2Pz)Fe II (OTf) 2 ( 1 ) with ( t BuSO 2 )C 6 H 4 IO at 298 K leads to the formation of the [Fe IV (O)(N2Py2Pz)] 2+ intermediate ( 2 ) with a near-IR band at 750 nm (ε M = 250 M −1 cm −1 ) and a t 1/2 ~ 2 min at 298 K. The introduction of the less basic pyrazolylmethyl ligands in place of two pyridylmethyl units generates Fe IV =O intermediate 2 that exhibits a cyclohexane oxidation rate of 0.29 s −1 at 298 K, which is 5,000-fold faster than that observed for the classic Fe IV (O)N4Py parent complex and 40,000-fold more reactive than the least reactive Fe IV (O)N2Py2Q′ complex in this series (Py = pyridine, Q′ = isoquinoline) recently reported by Nordlander.

Severe outcomes of COVID-19 among adults with increased risk conditions: A population-based observational study

Background The individual risk of severe outcomes following COVID-19 is poorly understood in populations with prior immunity. The lack of contemporary estimates limits support of timely diagnosis and antiviral treatment for individuals most likely to benefit. Objective To determine the risk of severe outcomes following COVID-19 within strata of comorbidities, including patients without documented infection. Design Population-based cohort study utilizing electronic medical records and g methods to account for selection bias in the documentation of COVID-19 illnesses. Setting A large health system in northeastern United States Patients Adults with increased risk conditions (90% vaccinated) and COVID-19 from June to December 2022. Measurements Incidence of composite of inpatient admission within 14 days and death within 28 days of COVID-19 diagnosis. Results An estimated 265,248 patients with at least one increased risk condition developed COVID-19, including 76,996 documented cases. Severe outcomes occurred in 3344 (1.3%) patients following COVID-19— 3147 (1.2%) hospitalizations and 376 (0.14%) deaths. In the absence of treatment, individuals with few increased risk conditions (MASS of 3 or less) accounted for 57% of infections and 0.7% developed severe outcomes. In contrast, 2.3% of patients with multiple increased risk conditions (MASS 4 or greater) or severe immunocompromise experienced severe outcomes, including 81% of deaths. The observed risk reduction with antiviral treatment was -0.1% (-0.2 to 0.02%), -0.6% (-0.9 to -0.4%), -1.3% (-2 to -1%), and -1.9% (-3 to -1%) for patients with MASS 3 or less, MASS 4 and 5, MASS 6 or greater, and severe immunocompromise, respectively. Limitations Estimated number COVID-19 cases cannot be directly verified Conclusions Individuals with multiple medical conditions remain at substantial risk for severe outcomes of COVID-19 and benefit from treatment.

Extreme two-phase change of ionospheric electron temperature overshoot during geomagnetic storms

Abstract An intense surge in the equatorial electron temperature (Te) at sunrise, known as the morning Te overshoot, has been one of the defining ionospheric features since its discovery early in the Space Age. Despite decades of study, the behavior of the morning overshoot during geomagnetic storms remains poorly understood. We report a two-stage response of the morning Te overshoot to geomagnetic activity, uncovered by a neural network model. Electron temperatures show an initial enhancement during the storm’s main phase, followed by a drastic depletion exceeding 1000 K and disappearance of the overshoot in the recovery phase. This two-phase change aligns with the early influence of westward prompt penetration electric field, overtaken by the development of the eastward disturbance dynamo later in the storm. These electric field changes affect vertical plasma drifts that redistribute electron densities, modifying ionospheric cooling rates. Our findings provide new insights into the dynamics of one of the most widely studied ionospheric features and showcase the potential of new-generation digital twin models of near-Earth space environment to reveal previously unrecognized physical patterns.

Co-zorbs: Motile, multispecies biofilms aid transport of diverse bacterial species

Biofilms are three-dimensional structures containing one or more bacterial species embedded in extracellular polymeric substances. Although most biofilms are stationary, Flavobacterium johnsoniae forms a motile spherical biofilm called a zorb, which is propelled by its base cells and contains a polysaccharide core. Here, we report the formation of spatially organized, motile, multispecies biofilms, designated “co-zorbs,” that are distinguished by a core–shell structure. F. johnsoniae forms zorbs whose cells collect other bacterial species and transport them to the zorb core, forming a co-zorb. Live imaging revealed that co-zorbs also form in zebrafish, thereby demonstrating a different type of bacterial movement in vivo. This finding opens different avenues for understanding community behaviors, the role of biofilms in bulk bacterial transport, and collective strategies for microbial success in various environments.

Bacterial targets of fecal host miRNAs in high-fat diet-fed mice

The gut microbiome composition is intricately linked to the host’s health status, yet the mechanisms underlying its interaction with the host are not fully understood. MicroRNAs (miRNAs), facilitating intercellular communication, are found in bodily fluids, including the intestinal content, where they may affect the microbiome. However, their role in type 2 diabetes (T2D)-associated microbiome and treatment implications are not explored. Our study investigated how host miRNAs may influence gut microbiome changes related to metformin treatment in a T2D mouse model. Analyzing fecal and gut mucosal samples via small RNA sequencing, we correlated results with microbiome sequencing data, identifying miRNA-microbiome correlations, bacterial targets, and proteins targeted in these bacteria. Significant differences in miRNA expression based on diet and intestinal location were noted, with minor effects from metformin treatment in the proximal small intestine of non-diabetic male mice. Key fecal miRNAs targeting bacteria included mmu-miR-5119, mmu-miR-5126, mmu-miR-6538, and mmu-miR-2137, primarily affecting Oscillospiraceae_NOV, Lachnospiraceae_NOV, and Bacteroides. Our analysis of targeted proteins revealed diverse biological and molecular effects. Further research into miRNA-bacteria interactions could lead to new strategies for manipulating the gut microbiome in T2D and beyond.

A novel lncRNA enhances autophagy to suppress extracellular matrix via modulating TP53INP1 in human trabecular meshwork cells under oxidative stress

Spatiotemporal distribution of the North American Indigenous population prior to European contact

We examine spatiotemporal trends in the pre-European-contact Indigenous population of North America using radiocarbon ( 14 C) dates of the past 2000 y. At a continental scale, the Indigenous population of the past ~14,000 y peaked at ~1150 CE and then declined until a brief recovery shortly before 1500 CE, after which 14 C probability declines precipitously. After testing, we reject the hypothesis that the 1150 CE peak and decline is a result of 14 C sampling issues. We then examine the 14 C record of the past 2000 y in each of 18 watersheds where we find peaks ranging from ~800 to 770 CE to after European contact, with the majority, in the interior of the continent, declining ~1080 to 1300 CE. Although all Indigenous populations declined after European contact, that of a large portion of the country (the Great Lakes, New England, the Mid-Atlantic, the Central Plains, the Northwest, and California) did not decline until after contact.

A splendid banana enigma: Phylogenomic assessment of Vietnamese Musa splendida and Musa viridis populations shows that they are conspecific

Species delimitation is essential to study and conserve biological diversity. It is traditionally based on morphological trait variation observed in one or a few specimens. Nevertheless, such assessments may not sufficiently take intraspecific trait variation into account, misidentifying morphotypes as separate species. The use of high-throughput sequencing data alongside morphological data in taxonomic studies may substantially improve the accuracy of taxonomic assessments. The Musa genus, commonly known for comprising the wild relatives of banana varieties, consists of about seventy described species. However, the taxonomic status of multiple Musa species is uncertain due to typification errors and the lack of high-quality specimens. The species M. splendida and M. viridis from northern Viet Nam only substantially differ from each other in the color of their male flower bracts, which is red to pinkish-red in M. splendida and pink in M. viridis. Consequently, their taxonomic status as separate species has been debated. Here, we studied the genetic relationships between 121 M. splendida and M. viridis plants using high-throughput sequencing data (DArTseq) in which we identified 51,188 single nucleotide polymorphisms. We found that individuals genetically clustered in a principal component analysis (6 clusters), fastStructure analysis (four groups), and ASTRAL-III consensus phylogenetic tree (nine clades) based on their population origin rather than by their taxon identity. In addition, a strong signal for an isolation-by-distance pattern between populations was observed. Plants identified as M. viridis were more closely related to M. splendida plants from the same region than to M. viridis plants from other regions. Hence, we propose to treat M. viridis as a synonym of M. splendida.

Triamcinolone acetonide and botulinum toxin A for upper eyelid retraction in thyroid-associated ophthalmopathy

The Regulatory-associated protein of target of rapamycin 1B (RAPTOR 1B) interconnects with the photoperiod pathway to promote flowering in <i>Arabidopsis</i>

The transition from vegetative to reproductive growth, or floral transition, is a tightly regulated, energy-demanding process. In Arabidopsis , the interplay of light perception and circadian rhythms detects changes in photoperiod length, accelerating flowering under long days (LD). CONSTANS (CO), a transcription factor, upregulates FLOWERING LOCUS T (FT) in leaves during dusk. The FT protein then moves to the shoot apical meristem, triggering the floral transition. While light and circadian signals control CO protein levels, less is known about how the nutrients/energy sensing regulates the photoperiod pathway for flowering modulation in this process. In our study, we identify the contribution of the Regulatory-associated protein of target of rapamycin 1B (RAPTOR1B), a component of the nutrient-sensing TOR complex (TORC), in the induction of specific flowering genes under CO control. While transcription of CO remains unaffected in raptor1b mutants, a reduction in its protein levels at dusk is observed compared to the wild type. Remarkably, the mutant also exhibits compromised GIGANTEA (GI) protein levels, crucial for CO stabilization during dusk. Our results indicate that the interaction and colocalization of RAPTOR1B with GI in the nucleus might influence GI levels through an unknown posttranscriptional mechanism. Genetic crosses position RAPTOR1B upstream of CO and GI. This is supported by phenotypic and molecular analyses. Our findings demonstrate that RAPTOR1B, likely as part of TORC, contributes to the photoperiod pathway of the flowering network, ensuring the timely initiation of floral transition under LD conditions.

PbTe quantum dots highly packed monolayer fabrication by a spin coating method

This study investigates the fabrication of large-area, highly-ordered monolayers of PbTe quantum dots (QDs) on TiO2/ITO substrate, using a fast, simple, and repeatable spin-coating technique. For the first time, a real monolayer (a layer with the height of a single QD) covering approximately 3 cm2 was successfully prepared, achieving a root-mean-square roughness (Rq) of 1.37 nm. The research systematically explores key parameters such as QD morphology, concentration, spin-coating conditions, substrate characteristics, wetting properties, and solvent effects to optimize thin film deposition. The findings reveal that the spin-coating method favors the formation of layers with spherical QDs (6–9 nm) over cubical QDs (10–13 nm). The findings highlight the significant influence of solvent evaporation rate, viscosity, and wettability on monolayer quality. Chloroform was identified as the optimal solvent for cubical QDs (~90% coverage), while hexane was more effective for spherical QDs (90%-100% coverage). Beyond monolayers, high-quality bilayers were also fabricated, demonstrating the method’s potential for multilayer fabrication. This rapid and efficient method for monolayer and bilayer fabrication marks a significant breakthrough in producing uniform, large-area films, facilitating seamless integration with existing technologies. It offers a scalable and cost-effective solution, opening the door to broader applications in fields that demand high-quality thin film deposition.

Dexamethasone as an adjuvant with ropivacaine in thoracoscopy guided thoracic paravertebral block for postoperative analgesia in thoracic surgery

Active vision in freely moving marmosets using head-mounted eye tracking

Our understanding of how vision functions as primates actively navigate the real-world is remarkably sparse. As most data have been limited to chaired and typically head-restrained animals, the synergistic interactions of different motor actions/plans inherent to active sensing—e.g., eyes, head, posture, movement, etc.—on visual perception are largely unknown. To address this considerable gap in knowledge, we developed an innovative wireless head-mounted eye-tracking system that performs Chair-free Eye-Recording using Backpack mounted micROcontrollers (CEREBRO) for small mammals, such as marmoset monkeys. Because eye illumination and environment lighting change continuously in natural contexts, we developed a segmentation artificial neural network to perform robust pupil tracking in these conditions. Leveraging this innovative system to investigate active vision, we demonstrate that although freely moving marmosets exhibit frequent compensatory eye movements equivalent to other primates, including humans, the predictability of the visual behavior (gaze) is higher when animals are freely moving relative to when they are head-fixed. Moreover, despite increases in eye/head-motion during locomotion, gaze stabilization remains steady because of an increase in vestibularocular reflex gain during locomotion. These results demonstrate the efficient, dynamic visuo-motor mechanisms and related behaviors that enable stable, high-resolution foveal vision in primates as they explore the natural world.

Acceptability and implementation potential of colorectal cancer screening and health literacy training: A qualitative study among general practitioners in deprived areas

Background Colorectal cancer (CRC) is a significant contributor to cancer-related burden, ranking second in cancer mortality in France. Despite the proven survival benefits of systematic CRC screening, uptake remains suboptimal, particularly among people with limited health literacy (HL) and lower socioeconomic position. This study aimed to assess the acceptability of an e-learning training programme on HL and CRC screening among general practitioners (GPs) in deprived areas while also exploring strategies for its promotion and scale-up. Methods A qualitative study nested within the DECODE cluster-randomised controlled trial (NCT04631692) across four French regions was conducted. Semi-structured interviews (phone or online) were carried out to capture opinions, experiences, and recommendations of GPs in the intervention arm. Thematic analysis, employing manual and NVivo coding, was performed. Results The majority of 22 GPs (16/22) found the training acceptable, informative, tailored to their knowledge needs and offering great flexibility of use. The module on HL garnered more interest than the one on CRC screening, as it addressed a relatively new area for many GPs. It facilitated reflection on patient communication techniques and identified areas for improvement in physician-patient interaction. A perceived gap in the training was the insufficient interactivity in both didactic and virtual group sessions. Conclusion The findings of this study show high acceptability of the e-learning training by participants, indicating a potential for implementation, if kept concise, self-paced, asynchronous, and with a stronger focus on HL. The training helped GPs reflect on their practices, enhance HL knowledge, and improve patient communication strategies, leading some to adopt new techniques in daily interactions with low HL patients, beyond just screening.

Association between neutrophil percentage to albumin ratio and short term prognosis of acute on chronic liver failure treated with artificial liver support system

Energyscapes pinpoint marine megafauna feeding hotspots in the Mediterranean

Ocean giants shape the structure and functioning of marine food webs via trophic top–down controls, landscapes of fear, vertical and horizontal redistribution of nutrients, energy, and matter. Yet, they face threats from overfishing, pollution, habitat degradation, and climate change, and one-third of marine megafauna species are at risk of extinction, ultimately endangering the resilience of entire ecosystems. In such a context, knowing when and where megafauna find resources to balance their substantial energy requirements is critical for their management. Through an energyscape approach integrating abundance censuses, diet, and energy requirements, we investigated the prey consumption patterns of Mediterranean marine megafauna during the summer. We thereby shed light on a diverse guild of species composed of fishes, mammals, reptiles, and birds and estimated that 4.1 million individuals consume 1.6 million tons of prey each summer, pelagic cephalopods being the primary food resource and cetaceans and tunas being key players in the community. Spatial patterns in prey consumption reflected the diverse distribution and needs of the megafauna species and underlined the critical importance of the western Mediterranean for the megafauna community. Conservation strategies should prioritize spatial and biological diversity to safeguard megafauna and ecosystem functions across the Mediterranean basin.

Antibodies response in symptomatic and asymptomatic SARS-CoV-2 infected persons in Thailand

Antibody assays of IgM, IgG and surrogate isotype independent virus neutralizing antibody (sVNT) targeting receptor binding domain of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) were employed in 97 real-time Reverse Transcription Polymerase Chain Reaction (RT-PCR) confirmed Coronavirus Disease 2019 (COVID-19) patients with varying severity admitted to King Chulalongkorn Memorial Hospital. Concordance rate was 100% regardless of severity, onset of symptoms and magnitude of viral load. Per available samples, antibodies appeared on the same day of symptom onset in one patient; one day after in 18 patients and two days after in 19 patients. In two patients, antibodies appeared as early as 4 days after infection (exposure). IgM and IgG were evident in all patients’ first assay (within two days of admission). sVNT was also evident within two days of admission in all but 3 patients. IgM usually remained positive during the entire course of hospital stay, where the longest in this study was 32 days. Antibody assays were also applied to samples collected at a State Quarantine premise from 77 asymptomatic Thais returning from Sudan in October. Virus was detected by real-time RT-PCR in 15 cases (day 0 = 6, day 3 = 4, day 5 = 4 and day 9 = 1). Twenty-nine (including 11 RT-PCR positive cases) were antibody positive on day 0, while 4 PCR positive with antibody negative on day 0 became antibody positive on day 14. Evaluation on antibody response at days 7 or 10 is needed to help build a case to shorten length of quarantine among negative cases.

Connectivity enhances resilience of marine forests after an extreme event

Abstract The resilience of populations to extreme climatic events comprises the resistance to withstand and the ability to recover, which depends on factors such as remaining genetic diversity and population connectivity. In 2011, a MHW caused a 100 km range contraction of kelp (Ecklonia radiata) off Western Australia, but recently recovering kelp forests were discovered. To understand mechanisms of recovery and determine if recovering populations are survivors or immigrants, we used genotyping-by-sequencing to assess patterns of genetic diversity and connectivity. We found that two of the three recovering kelp forests (PG1 and 2) were likely survivors whereas a third smaller population (PGCr 1) was likely produced through re-colonisation from nearby surviving forests. Connectivity was high among populations and migration analysis identified one population (Horrocks) as the most important source for the recovering kelps. All recovering populations had higher neutral genetic diversity, and similar putative adaptive diversity to surrounding surviving populations, suggesting local adaptation. Our results elucidate how mixed processes can contribute to kelp forest resilience following MHWs but cryptic survival and maintenance of population connectivity is key to recovery.