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Topological whirls or 'textures' of spins such as magnetic skyrmions represent the smallest realizable emergent magnetic entities1-5. They hold considerable promise as robust, nanometre-scale, mobile bits for sustainable computing6-8. A longstanding roadblock to unleashing their potential is the absence of a device enabling deterministic electrical readout of individual spin textures9,10. Here we present the wafer-scale realization of a nanoscale chiral magnetic tunnel junction (MTJ) hosting a single, ambient skyrmion. Using a suite of electrical and multimodal imaging techniques, we show that the MTJ nucleates skyrmions of fixed polarity, whose large readout signal-20-70% relative to uniformly magnetized states-corresponds directly to skyrmion size. The MTJ exploits complementary nucleation mechanisms to stabilize distinctly sized skyrmions at zero field, thereby realizing three non-volatile electrical states. Crucially, it can electrically write and delete skyrmions to both uniform states with switching energies 1,000 times lower than the state of the art. Here, the applied voltage emulates a magnetic field and, in contrast to conventional MTJs, it reshapes both the energetics and kinetics of the switching transition, enabling deterministic bidirectional switching. Our stack platform enables large readout and efficient switching, and is compatible with lateral manipulation of skyrmionic bits, providing the much-anticipated backbone for all-electrical skyrmionic device architectures9,10. Its wafer-scale realizability provides a springboard to harness chiral spin textures for multibit memory and unconventional computing8,11.
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Advanced reproductive technologies are utilized to identify the genetic mutations that lead to spermatogenic impairment, and allow informed genetic counseling to patients to prevent the transmission of genetic defects to offspring. The purpose of this study was to identify potential single nucleotide polymorphisms (SNPs) associated with male infertility. Genetic variants that may cause infertility are identified by combining the targeted next-generation sequencing (NGS) panel and whole exome sequencing (WES). The validation step of Sanger sequencing adds confidence to the identified variants. Our analysis revealed five distinct affected genes covering seven SNPs based on the targeted NGS panel and WES data: SPATA16 (rs16846616, 1515442, 1515441), CFTR (rs213950), KIF6 (rs2273063), STPG2 (r2903150), and DRC7 (rs3809611). Infertile men have a higher mutation rate than fertile men, especially those with azoospermia. These findings strongly support the hypothesis that the dysfunction of microtubule-related and spermatogenesis-specific genes contributes to idiopathic male infertility. The SPATA16, CFTR, KIF6, STPG2, and DRC7 mutations are associated with male infertility, specifically azoospermia, and a further examination of this genetic function is required.
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Azoospermia , Infertilidade Masculina , Humanos , Masculino , Azoospermia/genética , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Infertilidade Masculina/genética , Mutação , Família MultigênicaRESUMO
In order to realize the green computing of the edge-cloud fiber-wireless networks, the cooperation between the edge servers and the cloud servers is particularly important to reduce the network energy consumption. Therefore, this paper proposes an energy-efficient workload allocation (EEWA) scheme to improve the energy efficiency by using the architecture of edge-cloud fiber-wireless networks. The feasibility of the proposed EEWA scheme was verified on our SDN testbed. We also do the simulation to obtain the optimal results for a given set of task requests. Simulation results show that our proposed EEWA scheme greatly reduces the blocking probability and the average energy consumption of task requests in edge-cloud fiber-wireless networks.
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Erythropoietin (EPO) is known as a hormone for erythropoiesis in response to anemia and hypoxia. However, the effect of EPO is not only limited to hematopoietic tissue. Several studies have highlighted the neuroprotective function of EPO in extra-hematopoietic tissues, especially the retina. EPO could interact with its heterodimer receptor (EPOR/ßcR) to exert its anti-apoptosis, anti-inflammation and anti-oxidation effects in preventing retinal ganglion cells death through different intracellular signaling pathways. In this review, we summarized the available pre-clinical studies of EPO in treating glaucomatous optic neuropathy, optic neuritis, non-arteritic anterior ischemic optic neuropathy and traumatic optic neuropathy. In addition, we explore the future strategies of EPO for optic nerve protection and repair, including advances in EPO derivates, and EPO deliveries. These strategies will lead to a new chapter in the treatment of optic neuropathy.
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Eritropoetina , Doenças do Nervo Óptico , Traumatismos do Nervo Óptico , Neuropatia Óptica Isquêmica , Epoetina alfa , Eritropoetina/metabolismo , Eritropoetina/uso terapêutico , Humanos , Nervo Óptico/metabolismo , Doenças do Nervo Óptico/tratamento farmacológico , Traumatismos do Nervo Óptico/tratamento farmacológico , Neuropatia Óptica Isquêmica/tratamento farmacológico , Receptores da Eritropoetina/metabolismoRESUMO
Magnetic skyrmions are nanoscale topological spin structures offering great promise for next-generation information storage technologies. The recent discovery of sub-100-nm room-temperature (RT) skyrmions in several multilayer films has triggered vigorous efforts to modulate their physical properties for their use in devices. Here we present a tunable RT skyrmion platform based on multilayer stacks of Ir/Fe/Co/Pt, which we study using X-ray microscopy, magnetic force microscopy and Hall transport techniques. By varying the ferromagnetic layer composition, we can tailor the magnetic interactions governing skyrmion properties, thereby tuning their thermodynamic stability parameter by an order of magnitude. The skyrmions exhibit a smooth crossover between isolated (metastable) and disordered lattice configurations across samples, while their size and density can be tuned by factors of two and ten, respectively. We thus establish a platform for investigating functional sub-50-nm RT skyrmions, pointing towards the development of skyrmion-based memory devices.
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Arrays of 14 nm thick L10-FePt nanodots with diameter of 27 nm and center-to-center spacing of 39 nm were produced by block copolymer patterning of an FePt film and their magnetic reversal and thermal stability were characterized. A self-assembled polystyrene-b-polydimethylsiloxane diblock copolymer film was used as a lithographic mask and a pattern transfer process based on ion beam etching and rapid thermal annealing of the sputtered FePt film was developed. The dot arrays exhibited perpendicular magnetic anisotropy with K = 4.8 × 107 erg cm-3 and a saturation magnetization of 960 emu cm-3. First order reversal curves indicate a softer magnetic component attributed to the ion-milled material at the edges of the dots. The switching volume and the thermal stability were obtained from relaxation measurements and DC demagnetization curves. Micromagnetic simulations reproduce the magnetic domain structure obtained for the continuous and patterned FePt thin film.
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Turmeric, derived from Curcuma longa, and Lactobacillus paracasei, a lactic acid bacteria, have been studied for their potential antiobesity effects. To date, the antiobesity effects of turmeric fermented with L. paracasei have not been sufficiently investigated. This study was conducted via oral administration of 5% L. paracasei-fermented (FT) and unfermented turmeric (UT) in diet over 16 weeks using high-fat diet (HFD)-induced obese C57BL/6J mice. Results showed that the curcuminoid content of turmeric decreased following fermentation. Furthermore, FT significantly suppressed weight gain and liver and visceral adipose tissue weight and reduced plasma metabolic parameters in both the UT and FT experimental groups. The effects of FT were more noticeable than those of the unfermented form. Moreover, FT downregulated the expression of adipogenesis, lipogenesis, and inflammatory-related protein, but upregulated liver ß-oxidation protein SIRT 1, PPARα, and PGC-1α in perigonadal adipose tissue. Additionally, FT ameliorated insulin resistance by activating insulin receptor pathway protein expressions in visceral adipose tissues. FT also modulated gut microbiota composition, particularly in two beneficial bacteria, Akkermansia muciniphila and Desulfovibrio, as well as two short-chain fatty acid-producing bacteria: Muribaculum intestinale and Deltaproteobacteria. Our findings indicate that the modulation effect of FT may be an important pathway for its antiobesity mechanisms.
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Curcuma , Dieta Hiperlipídica , Fermentação , Microbioma Gastrointestinal , Lacticaseibacillus paracasei , Camundongos Endogâmicos C57BL , Obesidade , Animais , Microbioma Gastrointestinal/efeitos dos fármacos , Dieta Hiperlipídica/efeitos adversos , Obesidade/metabolismo , Obesidade/microbiologia , Camundongos , Curcuma/química , Curcuma/metabolismo , Masculino , Lacticaseibacillus paracasei/metabolismo , Humanos , Fármacos Antiobesidade/administração & dosagem , Adipogenia/efeitos dos fármacos , Fígado/metabolismo , Extratos Vegetais/administração & dosagem , Extratos Vegetais/farmacologia , PPAR alfa/metabolismo , PPAR alfa/genética , Resistência à Insulina , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/metabolismo , Bactérias/efeitos dos fármacosRESUMO
Some thermal degradants of curcuminoids have demonstrated moderate health benefits in previous studies. Feruloyl acetone (FER), recently identified as a thermal degradant of curcumin, has been previously associated with anticancer and antioxidative effects, yet its other capabilities remain unexplored. Moreover, earlier reports suggest that methoxy groups on the aromatic ring may influence the functionality of the curcuminoids. To address these gaps, an animal study was conducted to investigate the antiobesity effects of both FER and its demethoxy counterpart (DFER) on mice subjected to a high-fat diet. The results demonstrated the significant prevention of weight gain and enlargement of the liver and various adipose tissues by both samples. Furthermore, these supplements exhibited a lipid regulatory effect in the liver through the adiponectin/AMPK/SIRT1 pathway, promoted thermogenesis via AMPK/PGC-1α activation, and positively influenced gut-microbial-produced short-chain fatty acid (SCFA) levels. Notably, DFER demonstrated superior overall efficacy in combating obesity, while FER displayed a significant effect in modulating inflammatory responses. It is considered that SCFA may be responsible for the distinct effects of FER and DFER in the animal study. Future studies are anticipated to delve into the efficacy of curcuminoid degradants, encompassing toxicity and pharmacokinetic evaluations.
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Fármacos Antiobesidade , Curcumina , Dieta Hiperlipídica , Camundongos Endogâmicos C57BL , Obesidade , Animais , Curcumina/química , Curcumina/farmacologia , Curcumina/metabolismo , Camundongos , Obesidade/metabolismo , Obesidade/tratamento farmacológico , Masculino , Fármacos Antiobesidade/química , Fármacos Antiobesidade/administração & dosagem , Humanos , Dieta Hiperlipídica/efeitos adversos , Fígado/metabolismo , Fígado/efeitos dos fármacos , Fígado/química , Termogênese/efeitos dos fármacos , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Tecido Adiposo/químicaRESUMO
The interplay of magnetic interactions in chiral multilayer films gives rise to nanoscale topological spin textures that form attractive elements for next-generation computing. Quantifying these interactions requires several specialized, time-consuming, and resource-intensive experimental techniques. Imaging of ambient domain configurations presents a promising avenue for high-throughput extraction of parent magnetic interactions. Here, we present a machine learning (ML)-based approach to simultaneously determine the key magnetic interactionsâsymmetric exchange, chiral exchange, and anisotropyâgoverning the chiral domain phenomenology in multilayers, using a single binarized image of domain configurations. Our convolutional neural network model, trained and validated on over 10,000 domain images, achieved R2 > 0.85 in predicting the parameters and independently learned the physical interdependencies between magnetic parameters. When applied to microscopy data acquired across samples, our model-predicted parameter trends are consistent with those of independent experimental measurements. These results establish ML-driven techniques as valuable, high-throughput complements to conventional determination of magnetic interactions and serve to accelerate materials and device development for nanoscale electronics.
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Purpose: The Rho-associated protein kinase and myosin light chain kinase (ROCK/MYLK) pathway undeniably plays a pivotal role in the pathophysiology of primary open-angle glaucoma (POAG). In our study, we utilized both ocular hypertension (OHT) rabbit models and clinical investigations to gain invaluable insights that propel the development of novel treatments targeting proteins and genes associated with the trabecular meshwork (TM), thereby offering promising avenues for the management of POAG. Methods: Following microbead injections into the anterior chamber of the ocular cavity of rabbits, we observed elevated histiocyte numbers and immune scores for MYLK-4/ pMLC-2, alongside a reduction in the void space within the TM. Notably, treatment was performed with 0.1% ITRI-E-(S)-4046, a compound with dual kinase inhibitor (highly specific inhibitor of ROCK1/2 and MYLK4), significantly reduced intraocular pressure (IOP; P < 0.05) and expanded the void space within the TM (P < 0.0001) compared with OHT rabbits. In clinical investigations, we utilized whole transcriptome sequencing to analyze gene expression specifically related to the TM, obtained from patients (5 early-onset and 5 late-onset) undergoing trabeculectomy. Results: Our findings revealed 103 differential expression genes (DEGs) out of 265 molecules associated with the Rho family GTPase pathway, exhibiting a P value of 1.25E-10 and a z-score of -2.524. These results underscore significant differences between the early-onset and late-onset POAG and highlight the involvement of the ROCK/MYLK pathway. Conclusions: These findings underscore the critical involvement of the ROCK/MYLK pathway in both OHT-related and different onsets of POAG, providing valuable insights into the TM-related molecular mechanisms underlying the disease.
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Modelos Animais de Doenças , Glaucoma de Ângulo Aberto , Pressão Intraocular , Quinase de Cadeia Leve de Miosina , Hipertensão Ocular , Malha Trabecular , Quinases Associadas a rho , Animais , Malha Trabecular/metabolismo , Malha Trabecular/patologia , Quinases Associadas a rho/genética , Coelhos , Hipertensão Ocular/genética , Hipertensão Ocular/fisiopatologia , Hipertensão Ocular/metabolismo , Pressão Intraocular/fisiologia , Humanos , Glaucoma de Ângulo Aberto/genética , Glaucoma de Ângulo Aberto/metabolismo , Glaucoma de Ângulo Aberto/fisiopatologia , Quinase de Cadeia Leve de Miosina/genética , Quinase de Cadeia Leve de Miosina/metabolismo , Masculino , Feminino , Transdução de Sinais , Idoso , Pessoa de Meia-IdadeRESUMO
Obesity is a global health crisis, marked by excessive fat in tissues that function as immune organs, linked to microbiota dysregulation and adipose inflammation. Investigating the effects of Lactobacillus rhamnosus SG069 (LR069) and Lactobacillus brevis SG031 (LB031) on obesity and lipid metabolism, this research highlights adipose tissue's critical immune-metabolic role and the probiotics' potential against diet-induced obesity. Mice fed a high-fat diet were treated with either LR069 or LB031 for 12 weeks. Administration of LB031 boosted lipid metabolism, indicated by higher AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC) phosphorylation, and increased the M2/M1 macrophage ratio, indicating LB031's anti-inflammatory effect. Meanwhile, LR069 administration not only led to significant weight loss by enhancing lipolysis which evidenced by increased phosphorylation of hormone-sensitive lipase (HSL) and adipose triglyceride lipase (ATGL) but also elevated Akkermansia and fecal acetic acid levels, showing the gut microbiota's pivotal role in its antiobesity effects. LR069 and LB031 exhibit distinct effects on lipid metabolism and obesity, underscoring their potential for precise interventions. This research elucidates the unique impacts of these strains on metabolic health and highlights the intricate relationship between gut microbiota and obesity, advancing our knowledge of probiotics' therapeutic potential.
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Spintronics-based artificial neural networks (ANNs) exhibiting nonvolatile, fast, and energy-efficient computing capabilities are promising neuromorphic hardware for performing complex cognitive tasks of artificial intelligence and machine learning. Early experimental efforts focused on multistate device concepts to enhance synaptic weight precisions, albeit compromising on cognitive accuracy due to their low magnetoresistance. Here, we propose a hybrid approach based on the tuning of tunnel magnetoresistance (TMR) and the number of states in the compound magnetic tunnel junctions (MTJs) to improve the cognitive performance of an all-spin ANN. A TMR variation of 33-78% is controlled by the free layer (FL) thickness wedge (1.6-2.6 nm) across the wafer. Meanwhile, the number of resistance states in the compound MTJ is manipulated by varying the number of constituent MTJ cells (n = 1-3), generating n + 1 states with a TMR difference between consecutive states of at least 21%. Using MNIST handwritten digit and fashion object databases, the test accuracy of the compound MTJ ANN is observed to increase with the number of intermediate states for a fixed FL thickness or TMR. Meanwhile, the test accuracy for a 1-cell MTJ increases linearly by 8.3% and 7.4% for handwritten digits and fashion objects, respectively, with increasing TMR. Interestingly, a multifarious TMR dependence of test accuracy is observed with the increasing synaptic complexity in the 2- and 3-cell MTJs. By leveraging on the bimodal tuning of multilevel and TMR, we establish viable paths for enhancing the cognitive performance of spintronic ANN for in-memory and neuromorphic computing.
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The quest to mimic the multistate synapses for bioinspired computing has triggered nascent research that leverages the well-established magnetic tunnel junction (MTJ) technology. Early works on the spin transfer torque MTJ-based artificial neural network (ANN) are susceptible to poor thermal reliability, high latency, and high critical current densities. Meanwhile, work on spin-orbit torque (SOT) MTJ-based ANN mainly utilized domain wall motion, which yields negligibly small readout signals differentiating consecutive states and has designs that are incompatible with technological scale-up. Here, we propose a multistate device concept built upon a compound MTJ consisting of multiple SOT-MTJs (number of MTJs, n = 1-4) on a shared write channel, mimicking the spin-based ANN. The n + 1 resistance states representing varying synaptic weights can be tuned by varying the voltage pulses (±1.5-1.8 V), pulse duration (100-300 ns), and applied in-plane fields (5.5-10.5 mT). A large TMR difference of more than 13.6% is observed between two consecutive states for the 4-cell compound MTJ, a 4-fold improvement from reported state-of-the-art spin-based synaptic devices. The ANN built upon the compound MTJ shows high learning accuracy for digital recognition tasks with incremental states and retraining, achieving test accuracy as high as 95.75% in the 4-cell compound MTJ. These results provide an industry-compatible platform to integrate these multistate SOT-MTJ synapses directly into neuromorphic architecture for in-memory and unconventional computing applications.
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Geopolymer materials have excellent properties such as high strength, low thermal conductivity, fire resistance, acid and alkali resistance, and low carbon emissions. They can be used as protective engineering materials in places with explosion risks. At present, the common composite blast resistant panel is in the form of a sandwich: the outer layer isgalvanized steel plate, and fiber cement board or calcium carbonate board is used as the inner layer material, as these boards have the advantages of easy installation, good fire resistance, and explosion resistance. This study investigates the effect of adding different types of fibers to geopolymer mortar on the mortar's basic mechanical properties, such as compression strength, bending strength, and impact resistance. The explosive resistance of the fiber-reinforced geopolymer mortar blast resistant panels was evaluated through free-air explosion. In this paper, experimental procedures and numerical simulation have been performed to study the failure modes, maximum deflection, and dynamic response of the fiber-reinforced geopolymer mortar blast resistant panel under free-air explosion. The research results can provide a reference for the design and production of blast resistant panels.
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Benzo[a]pyrene (B[a]P) is a genotoxic polycyclic aromatic hydrocarbon that is metabolized by cytochrome P450 family 1 enzymes (CYP 1s) and can bind to DNA to form DNA adducts, leading to DNA damage and increased colorectal cancer risk. Previous studies have shown polymethoxyflavones to have a high potential for anticancer effects by regulating CYP 1s, especially nobiletin (NBT) and 5-demethylnobiletin (5-DMNB). However, the effects of NBT and 5-DMNB on B[a]P metabolism remain unclear. Therefore, this study aimed to clarify the effects of NBT and 5-DMNB on B[a]P-induced DNA damage in vitro and in vivo. In NCM460 cells, 5-DMNB and NBT appeared to reduce the metabolic conversion of B[a]P by regulating the aryl hydrocarbon receptor (AhR)/CYP 1s signaling pathway. This process protected NCM460 cells from B[a]P's cytotoxic effects by decreasing DNA damage and suppressing B[a]P diol-epoxide-DNA adduct formation. In BALB/c mice, 5-DMNB and NBT also protected against B[a]P-induced DNA damage. Altogether, these findings indicate that 5-DMNB and NBT attenuate B[a]P-induced DNA damage by modulating biotransformation, highlighting their chemopreventive potential against B[a]P-induced carcinogenesis. Therefore, 5-DMNB and NBT are promising agents for colorectal cancer chemoprevention in the future.
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Benzo(a)pireno , Neoplasias Colorretais , Camundongos , Animais , Benzo(a)pireno/toxicidade , Benzo(a)pireno/metabolismo , Xenobióticos , Dano ao DNA , Adutos de DNA , Neoplasias Colorretais/induzido quimicamente , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genéticaRESUMO
Purple Pennisetum (Pennisetum purpureum Schumach), a hybrid between Taihucao No. 2 and the local wild species of purple Pennisetum, has dark red stems and leaves due to its anthocyanin content. This study explores the potential of purple napiergrass extracts (PNE) in alleviating obesity and metabolic disorders induced by a high-fat diet in mice, where 50% of the caloric content is derived from fat. Mice were orally administered low-dose or high-dose PNE alongside a high-fat diet. Experimental findings indicate that PNE attenuated weight gain, reduced liver, and adipose tissue weight, and lowered blood cholesterol, triglyceride, low-density lipoprotein, and blood sugar levels. Stained sections showed that PNE inhibited lipid accumulation and fat hypertrophy in the liver. Immunoblotting analysis suggested that PNE improved the inflammatory response associated with obesity, dyslipidemia, and hyperglycemia induced by a high-fat diet. Furthermore, PNE potentially functions as a PPAR-γ agonist, increasing the adiponectin (ADIPOQ) concentration and suppressing inflammatory factors, while elevating the anti-inflammatory factor interleukin-10 (IL-10) in the liver. PNE-treated mice showed enhanced activation of the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) and AMP-activated protein kinase (AMPK) pathways and increased fatty acid oxidation and liver lipolysis. In conclusion, this study elucidated the mechanisms underlying the anti-inflammatory, PI3K/Akt, and AMPK pathways in a high-fat diet-induced obesity model. These findings highlight the potential of PNE in reducing weight, inhibiting inflammation, and improving blood sugar and lipid levels, showing the potential for addressing obesity-related metabolic disorders in humans.
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Doenças Metabólicas , Pennisetum , Humanos , Camundongos , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Pennisetum/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Dieta Hiperlipídica/efeitos adversos , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Glicemia/metabolismo , Extratos Vegetais/farmacologia , Obesidade/tratamento farmacológico , Obesidade/etiologia , Fígado/metabolismo , Triglicerídeos/metabolismo , Água/metabolismo , Doenças Metabólicas/tratamento farmacológico , Doenças Metabólicas/etiologia , Doenças Metabólicas/metabolismo , Anti-Inflamatórios/metabolismo , Camundongos Endogâmicos C57BLRESUMO
SCOPE: The aging biomarkers are alternatives and none of them can act as a strong predictor of frailty during the progression of aging. Several studies reveal the relationship between metabolites and frailty or gut microbiota and frailty. However, the connection between metabolites and gut microbiota in non-robust older adults has not been discussed yet. The study aims to combine the findings of serum metabolites and gut microbiota in non-robust subjects as a possible diagnostic biomarker. METHODS AND RESULTS: Frailty-related assessments are conducted to ensure the discrimination of non-robustness. The serum and fecal are collected for serum metabolomics and gut microbiota analysis. Robust and non-robust subjects show very different gut microbial compositions. Among the gut microbial differences, Escherichia/Shigella and its higher taxonomic ranks are found to have the most discriminative abundance among compared groups. More importantly, the abundance of Escherichia/Shigella is found to be positively correlated (p < 0.05) with the level of discriminant metabolites, such as serum oxoglutarate, glutamic acid, and 1-methyladenosine. CONCLUSION: These results indicate the obvious interrelation between gut microbiota and serum metabolites in non-robust older adults. Besides, the findings suggest that Escherichia/Shigella can be a potential biomarker candidate for robustness sub-phenotypic identification.
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Fragilidade , Microbioma Gastrointestinal , Humanos , Idoso , Estudos Transversais , Envelhecimento , Fezes , Biomarcadores , RNA Ribossômico 16SRESUMO
Use of online social networks (OSNs) undoubtedly brings the world closer. OSNs like Twitter provide a space for expressing one's opinions in a public platform. This great potential is misused by the creation of bot accounts, which spread fake news and manipulate opinions. Hence, distinguishing genuine human accounts from bot accounts has become a pressing issue for researchers. In this paper, we propose a framework based on deep learning to classify Twitter accounts as either 'human' or 'bot.' We use the information from user profile metadata of the Twitter account like description, follower count and tweet count. We name the framework 'DeeProBot,' which stands for Deep Profile-based Bot detection framework. The raw text from the description field of the Twitter account is also considered a feature for training the model by embedding the raw text using pre-trained Global Vectors (GLoVe) for word representation. Using only the user profile-based features considerably reduces the feature engineering overhead compared with that of user timeline-based features like user tweets and retweets. DeeProBot handles mixed types of features including numerical, binary, and text data, making the model hybrid. The network is designed with long short-term memory (LSTM) units and dense layers to accept and process the mixed input types. The proposed model is evaluated on a collection of publicly available labeled datasets. We have designed the model to make it generalizable across different datasets. The model is evaluated using two ways: testing on a hold-out set of the same dataset; and training with one dataset and testing with a different dataset. With these experiments, the proposed model achieved AUC as high as 0.97 with a selected set of features.
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Anxiety and depression are increasingly prevalent in adolescents, often causing daily distress and negative long-term outcomes. Despite the significant and growing burden, less than 25% of those with probable diagnosis of anxiety and depression are receiving help in England. Significant barriers to help-seeking exist in this population, with a scarcity of easily accessible, effective, and cost-effective interventions tailored specially for this age group. One intervention that has been shown to be feasible to deliver and with the promise of reducing stress in this age group is a school-based stress workshop programme for 16-18-year-olds (herein called DISCOVER). The next step is to rigorously assess the effectiveness, and cost-effectiveness, of the DISCOVER intervention in a fully powered cluster randomised controlled trial (cRCT). If found to be clinically and cost-effective, DISCOVER could be scaled up as a service model UK-wide and have a meaningful impact on the mental health of adolescents across the country.Trial registration: ISRCTN registry ISRCTN90912799. Registered with ISRCTN 28 May 2020.
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Ansiedade , Instituições Acadêmicas , Adolescente , Humanos , Ansiedade/diagnóstico , Ansiedade/terapia , Ansiedade/psicologia , Saúde Mental , Transtornos de Ansiedade , Análise Custo-Benefício , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
Magnetic skyrmions are nanoscale spin textures touted as next-generation computing elements. When subjected to lateral currents, skyrmions move at considerable speeds. Their topological charge results in an additional transverse deflection known as the skyrmion Hall effect (SkHE). While promising, their dynamic phenomenology with current, skyrmion size, geometric effects and disorder remain to be established. Here we report on the ensemble dynamics of individual skyrmions forming dense arrays in Pt/Co/MgO wires by examining over 20,000 instances of motion across currents and fields. The skyrmion speed reaches 24 m/s in the plastic flow regime and is surprisingly robust to positional and size variations. Meanwhile, the SkHE saturates at â¼22∘, is substantially reshaped by the wire edge, and crucially increases weakly with skyrmion size. Particle model simulations suggest that the SkHE size dependence - contrary to analytical predictions - arises from the interplay of intrinsic and pinning-driven effects. These results establish a robust framework to harness SkHE and achieve high-throughput skyrmion motion in wire devices.