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1.
J Hazard Mater ; 441: 129883, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36108495

RESUMO

Cadmium (Cd) and lead (Pb) are two of the most common elements found in contaminated sites. The behavior of specific metals in the soil may be affected by other metals because of the competition for adsorption sites. In this study, adsorption experiments after chemical extraction, multi-surface models, and advanced spectroscopy technology were jointly used to explain the adsorption mechanism of Cd and Pb and to determine the contribution of each component in the competitive system. The results show that pH is the key factor in determining the contribution of soil components to metal adsorption. Soil organic matter (SOM) is the dominant adsorbent for both Cd and Pb. Clay minerals play an adsorption role at low pH, whereas Fe/Al oxides adsorb metals primarily in the high pH range. Further, the competitive effect of Pb on Cd occurred primarily on SOM rather than on clay minerals. When the Pb concentration increased from 0 to 500 mg/L, the adsorption of Cd on SOM decreased by 132.0 mg/kg, whereas it decreased only by 1.9 mg/kg on clay minerals. Therefore, the competitive effect of Pb on Cd cannot be ignored in soils with high organic matter content.


Assuntos
Metais Pesados , Poluentes do Solo , Adsorção , Cádmio/química , Argila , Chumbo/análise , Metais Pesados/análise , Minerais , Óxidos/análise , Solo/química , Poluentes do Solo/análise
2.
Horm Metab Res ; 54(2): 84-93, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35130569

RESUMO

Long-term glycemic fluctuation has been associated with cardiovascular risk in patients with type 2 diabetes mellitus (T2DM). However, the findings are inconsistent. We performed a meta-analysis to summarize the association between parameters of long-term glycemic variability and risk of cardiovascular events in T2DM patients. Medline, Embase, and Web of Science databases were searched for longitudinal follow-up studies comparing the incidence of cardiovascular events in T2DM patients with higher or lower long-term glycemic variability. A random-effect model incorporating the potential heterogeneity among the included studies was used to pool the results. Twelve follow-up studies with 146 653 T2DM patients were included. The mean follow-up duration was 4.9 years. Pooled results showed that compared to those with the lowest glycemic variability, patients with the highest glycemic variability had significantly increased risk of cardiovascular events, as evidenced by the standard deviation of glycated hemoglobin [HbA1c-SD: relative risk (RR)=1.44, 95% confidence interval (CI): 1.23 to 1.69, p<0.001; I2=70%], HbA1c coefficient of variation (HbA1c-CV: RR=1.46, 95% CI: 1.19 to 1.79. p<0.001; I2=83%), standard deviation of fasting plasma glucose (FPG-SD: RR=1.33, 95% CI: 1.07 to 1.65, p=0.009; I2=0%), and FPG coefficient of variation (FPG-CV: RR=1.29, 95% CI: 1.01 to 1.64, p=0.04; I2=47%). In conclusion, increased long-term glycemic variability may be an independent risk factor for cardiovascular events in T2DM patients.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Glicemia , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Diabetes Mellitus Tipo 2/complicações , Jejum , Hemoglobina A Glicada/análise , Humanos , Fatores de Risco
3.
Front Cardiovasc Med ; 9: 827860, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35369329

RESUMO

Background: The thoracoscopic trans-mitral approach can not only facilitate exposure of the ventricular septum, mitral valve, and subvalvular apparatus, it also enables the surgeons to perform concomitant mitral valve intervention. This study aimed to determine the safety and efficacy of thoracoscopic trans-mitral septal myectomy in elderly patients with hypertrophic obstructive cardiomyopathy (HOCM). Methods: We reviewed the demographic to clinical characteristics and outcomes of patients who underwent thoracoscopic trans-mitral septal myectomy in our center between April 2019 and April 2021. The population was divided into a younger group (<60 years) and an elderly group (≥60 years). Results: There were 46 and 20 patients in the younger and elderly groups, respectively. The majority of patients in the elderly group were female (39.1 vs. 80.0%, P < 0.01). Patients in the elderly group were more likely to be in New York Heart Association Class IV (2.2 vs. 80.0%, P < 0.01). The European System for Cardiac Operation Risk Evaluation II predicted mortality rates were significantly higher (3.97 ± 1.81 vs. 1.62 ± 0.86%, P < 0.01) in the elderly group. In the elderly group, a patient converted to median sternotomy due to left ventricular posterior free wall rupture following septal myectomy and mitral bioprosthetic valve replacement. The patient then underwent double-patch sandwich repair for rupture and mitral mechanical valve replacement and was eventually discharged. All patients in the elderly group were discharged, while one in the younger group died. No patient in the elderly group required permanent pacemaker implantation vs. one in the younger group. Patients in the elderly group were more likely to spend more time in the intensive care unit than those in the younger group (5.44 ± 5.80 days vs. 3.07 ± 2.72, P < 0.05). However, there was no significant intergroup difference in in-hospital mortality or complications. Importantly, the left ventricular outflow tract pressure gradient was significantly decreased from 96.15 ± 32.89 mmHg to 8.2 ± 3.42 mmHg with no residual obstruction in the elderly group. The interventricular septal thickness was significantly decreased from 19.73 ± 3.14 mm to 11.30 ± 2.23 mm. Postoperative mitral regurgitation severity was significantly improved in the elderly group. Conclusion: This study demonstrated that thoracoscopic trans-mitral septal myectomy is a feasible option for selected elderly patients with satisfactory outcomes similar to those of young patients.

4.
Curr Med Sci ; 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36190598

RESUMO

OBJECTIVE: To evaluate the feasibility of using gadopentetate dimeglumine (Gd-DTPA) for dual-energy computed tomography pulmonary angiography (CTPA). METHODS: Sixty-six patients were randomly divided into three groups and underwent CTPA. Group A had a turbo flash scan using an iohexol injection, Group B had a turbo flash scan using Gd-DTPA, and Group C had a dual-energy scan using Gd-DTPA. The original images of Group C were linearly blended with a blending factor of 0.5 or reconstructed at 40, 50, 60, 70, 80, 90, 100, and 110 keV, respectively. The groups were compared in terms of pulmonary artery CT value, image quality, and radiation dose. RESULTS: The pulmonary artery CT values were significantly higher in Group C40keV than in Groups B and C, but lower than in Group A. There was no significant difference in the image noise of Groups C40keV, B, and C. Moreover, Group A had the largest beam hardening artifacts of the superior vena cava (SVC), followed by Groups B and C. Group C40keV showed better vascular branching than the other three groups, among which Group B was superior to Group A. The subjective score of the image quality of Groups A, B, and C showed no significant difference, but the score was significantly higher in Group C40keV than in Groups A and B. The radiation dose was significantly lower in Group B than in Groups A and C. CONCLUSION: Gd-CTPA is recommended to patients who are unsuitable for receiving an iodine-based CTPA. Furthermore, a turbo flash scan could surpass a dual-energy scan without consideration for virtual monoenergetic imaging.

5.
Cureus ; 14(8): e28606, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36185932

RESUMO

Objective To improve the efficiency of frame-based and frameless Gamma Knife® Icon™ (GKI) treatments by analyzing the workflows of both treatment approaches and identifying steps that lead to prolonged patient in-clinic or treatment time. Methods The treatment processes of 57 GKI patients, 16 frame-based and 41 frameless cases were recorded and analyzed. For frame-based treatments, time points were recorded for various steps in the process, including check-in, magnetic resonance imaging (MRI) completion, plan approval, and treatment start/end times. The time required for completing each step was calculated and investigated. For frameless treatments, the actual and planned treatment times were compared to evaluate the patient tolerance of the treatment. In addition, the time spent on room cleaning and preparation between treatments was also recorded and analyzed. Results For frame-based cases, the average in-clinic time was 6.3 hours (ranging from 4 to 8.7 hours). The average time from patient check-in to plan approval was 4.2 hours (ranging from 2.8 to 5.5 hours), during which the frame was placed, stereotactic reference MRI images were taken, target volumes were contoured, and the treatment plan was developed and second-checked. For patients immobilized with a mask, treatment pauses triggered by the intra-fractional motion monitoring system resulted in a significantly longer actual treatment time than the planned time. In 50 (or 55%) of the 91 frameless treatments, the patient on-table time was longer than the planned treatment time by more than 10 minutes, and in 19 (or 21%) of the treatments the time difference was larger than 20 minutes. Major treatment interruptions, defined as pauses leading to a longer than 10-minute delay, were more commonly encountered in patients with a planned treatment time longer than 40 minutes, which accounted for 64% of the recorded major interruptions. Conclusion For frame-based cases, the multiple pretreatment steps (from patient check-in to plan approval) in the workflow were time-consuming and resulted in prolonged patient in-clinic time. These pretreatment steps may be shortened by performing some of these steps before the treatment day, e.g., pre-planning the treatment using diagnostic MRI scans acquired a few days earlier. For frameless patients, we found that a longer planned treatment time is associated with a higher chance of treatment interruption. For patients with a long treatment time, a planned break or consideration of fractionated treatments (i.e., 3 to 5 fractionated stereotactic radiosurgery) may optimize the workflow and improve patient satisfaction.

6.
Front Genet ; 13: 1013178, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36186450

RESUMO

Background: The effects of fatty acid metabolism in many tumors have been widely reported. Due to the diversity of lipid synthesis, uptake, and transformation in clear cell renal cell carcinoma (ccRCC) cells, many studies have shown that ccRCC is associated with fatty acid metabolism. The study aimed was to explore the impact of fatty acid metabolism genes on the prognosis and immunotherapy of ccRCC. Methods: Two subtypes were distinguished by unsupervised clustering analysis based on the expression of 309 fatty acid metabolism genes. A prognostic model was constructed by lasso algorithm and multivariate COX regression analysis using fatty acid metabolism genes as the signatures. The tumor microenvironment between subtypes and between risk groups was further analyzed. The International Cancer Genome Consortium cohort was used for external validation of the model. Results: The analysis showed that subtype B had a poorer prognosis and a higher degree of immune infiltration. The high-risk group had a poorer prognosis and higher tumor microenvironment scores. The nomogram could accurately predict patient survival. Conclusion: Fatty acid metabolism may affect the prognosis and immune infiltration of patients with ccRCC. The analysis was performed to understand the potential role of fatty acid metabolism genes in the immune infiltration and prognosis of patients. These findings have implications for individualized treatment, prognosis, and immunization for patients with ccRCC.

7.
Front Pharmacol ; 13: 943812, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36188594

RESUMO

Purpose: The "radiotherapy-pharmacokinetic" ("RT-PK") phenomenon refers to the fact that radiation can significantly alter the pharmacokinetic behavior of a drug. At present, it is not clear whether there is an "RT-PK" phenomenon that can affect apatinib during concurrent chemoradiotherapy. In this study, we used a rat irradiation model to study the effects of X-ray radiation on absorption, tissue distribution, and excretion of apatinib. Method: Healthy Sprague-Dawley (SD) rats were randomly divided into control and radiation groups. The radiation group was given an appropriate dose of abdominal X-ray radiation, while the control group was not given irradiation. After 24 h of recovery, both groups were given apatinib solution 45 mg/kg by gavage. A quantitative LC-MS/MS method was developed to determine the concentration of apatinib in the rats, so as to compare the differences between the control and radiation groups and thus investigate the modulating effect of radiation on the pharmacokinetics of apatinib in rats. Results: After abdominal X-ray irradiation, the area under the curve (AUC0-t) of apatinib in rat plasma decreased by 33.8% and 76.3% at 0.5 and 2 Gy, respectively. Clearance (CL) and volume of distribution (Vd) increased and were positively correlated with radiation dose. X-ray radiation significantly reduced the concentration of apatinib in the liver and small intestine, and there was no tissue accumulation. In excretion studies, we found that X-ray radiation reduced the cumulative excretion of apatinib in feces and urine by 11.24% and 86.17%, respectively. Conclusion: Abdominal X-ray radiation decreased plasma exposure, tissue distribution, and excretion of apatinib in rats, suggesting that the RT-PK phenomenon affects apatinib. We speculate that this RT-PK phenomenon is closely related to changes in metabolic enzymes in vivo. In clinical practice, when apatinib is combined with radiotherapy, attention should be paid to adjusting the dose of apatinib and optimizing the treatment plan to alleviate the adverse effects of this RT-PK phenomenon.

8.
Clin Chim Acta ; 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36191610

RESUMO

OBJECTIVE: Venous thromboembolism (VTE) is a common and severe complication of joint arthroplasty. Microparticles (MPs) containing phosphatidylserine (PS) and tissue factor (TF) can trigger coagulation in VTE. This study aims to measure and compare MP levels in joint arthroplasty patients with and without VTE. METHODS: This prospective cohort study enrolled 181 patients who underwent joint arthroplasty. Ultrasound examination was used to diagnose VTE on preoperative day 0 and postoperative day 6. MPs were analysed using transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA), and flow cytometry. The levels of platelet-derived microparticles (PMPs), endothelial cell-derived microparticles (EMPs), granulocyte-derived microparticles (GMPs), red cell-derived microparticles (RMPs), monocyte-derived microparticles (MMPs), Annexin V+ MPs (AV+ MPs), and tissue factor+ MPs (TF+ MPs) derived from five kinds of MPs were measured on day 0 (before surgery), 1, 2, 3, 4, 5, and 6 after surgery. RESULTS: The levels of AV-TF+ EMPs and AV-TF+ MMPs were significantly increased in patients with VTE on postoperative day 5 compared to those without VTE (P=0.031 and P=0.031, respectively). CONCLUSION: AV-TF+ MPs may indicate the development of VTE and serve as predictive markers in joint arthroplasty patients.

9.
Patient Prefer Adherence ; 16: 2695-2707, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36196067

RESUMO

Purpose: Trial participation and adherence to interventions can directly influence the evaluation of outcomes in clinical trials for real world applications. The factors that influence trial participation and adherence to Tai Chi interventions in people with cardiovascular diseases remains unknown. This study aimed to explore participants' perceptions of influential factors on their trial participation and adherence to a Tai Chi intervention within a trial setting. Patients and Methods: Participants had coronary heart disease and/or hypertension in a randomized controlled trial comparing Tai Chi with a waitlist control. Data were collected via face-to-face, semi-structured interviews and analyzed using thematic analysis. Results: Thirty-four participants from the Tai Chi group who completed the randomized trial were interviewed. Six dominating themes and four sub-themes are discussed under the facilitators of internal and external motivation, positive feelings, benefits of Tai Chi and future practice with an overall internal motivation to improve health. Positive feelings had three sub-themes: positive feelings toward Tai Chi, the project, and the learning experience. The Tai Chi instructor(s) was found to be a crucial element in motivating participants' adherence to Tai Chi. Conclusion: From the perception of participants, the facilitators to their trial participation and adherence to a Tai Chi intervention included internal and external motivation, positive feelings towards Tai Chi, the project and the learning experience, and perceived benefits of Tai Chi. Perceived barriers included concerns about the safety and complexity of Tai Chi practice, lack of group atmosphere outside of class, and scheduling conflicts. Future researchers can address these factors to improve trial recruitment and implementation of Tai Chi and other mind-body interventions in research and for real world applications.

10.
Mater Today Bio ; 16: 100415, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36105673

RESUMO

Myocardium is an excitable tissue with electrical conductivity and mechanical strength. In this work, carbon fibers (CFs) and co-axial fibrous mesh were integrated which combined the high modulus and excellent electrical conductivity of CFs and the fibrous and porous structures of the electrospun fibers. The scaffold was fabricated by simply integrating coaxial electrospun fibers and carbon fibers through a freeze-drying procedure. It was shown that the integration of carbon fibers have the conductivity and Young's modulus of the fibrous mesh increased significantly, meanwhile, upregulated the expression of CX43, α-actinin, RhoA of the neonatal rat primary cardiomyocytes and primary human umbilical vein endothelial cells (HUVECs), and promoted the secretion of VEGF of HUVECs. Moreover, the cardiomyocytes grown on the scaffolds increased the ability of HUVECs migration. When implanted to the injury area post myocardial infraction, the scaffolds were able to effectively enhance the tissue regeneration and new vessel formation, which rescued the heart dysfunction induced by the myocardial infraction, evidenced by the results of echocardiography and histochemical analysis. In conclusion, the composite scaffolds could promote the myocardium regeneration and function's recovery by enhancing cardiomyocytes maturation and angiogenesis and establishing the crosstalk between the cardiomyocytes and the vascular endothelial cells.

11.
ACS Appl Mater Interfaces ; 14(36): 40546-40558, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36059107

RESUMO

Hypoxia-activated prodrugs (HAPs) have drawn increasing attention for improving the antitumor effects while minimizing side effects. However, the heterogeneous distribution of the hypoxic region in tumors severely impedes the curative effect of HAPs. Additionally, most HAPs are not amenable to optical imaging, and it is difficult to precisely trace them in tissues. Herein, we carefully designed and synthesized a multifunctional therapeutic BAC prodrug by connecting the chemotherapeutic drug camptothecin (CPT) and the fluorescent photothermal agent boron dipyrromethene (BODIPY) via hypoxia-responsive azobenzene linkers. To enhance the solubility and tumor accumulation, the prepared BAC was further encapsulated into a human serum albumin (HSA)-based drug delivery system to form HSA@BAC nanoparticles. Since the CPT was caged by a BODIPY-based molecule at the active site, the BAC exhibited excellent biosafety. Importantly, the activated CPT could be quickly released from BAC and could perform chemotherapy in hypoxic cancer cells, which was ascribed to the cleavage of the azobenzene linker by overexpressed azoreductase. After irradiation with a 730 nm laser, HSA@BAC can efficiently generate hyperthermia to achieve irreversible cancer cell death by oxygen-independent photothermal therapy. Under fluorescence imaging-guided local irradiation, both in vitro and in vivo studies demonstrated that HSA@BAC exhibited superior antitumor effects with minimal side effects.


Assuntos
Hipertermia Induzida , Nanopartículas , Neoplasias , Pró-Fármacos , Compostos Azo , Boro , Compostos de Boro , Camptotecina/química , Linhagem Celular Tumoral , Humanos , Hipóxia , Nanopartículas/química , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Fototerapia , Terapia Fototérmica , Porfobilinogênio/análogos & derivados , Pró-Fármacos/química
12.
Bioinformatics ; 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36111859

RESUMO

MOTIVATION: Large-scale heterogeneous data provides diverse perspectives for predicting drug-protein interactions (DPIs). However, the available information on molecular interactions and clinical associations related to drugs or proteins is incomplete because there may be unproven interactions and associations. This incomplete information in the available data is presented in the form of non-interaction and non-correlation, which may mislead the prediction model. Existing methods fuse incomplete and complete information without considering their integrity, so the negative effects of incomplete information still exist. RESULTS: We develop a network-based DPI prediction method named BRWCP, which uses the complete information network to correct the prediction results acquired by the incomplete information network. By integrating relevant heterogeneous information that may be incomplete, the feature similarities of drugs and proteins are obtained. Combining the feature similarities and known DPIs, an incomplete information-based drug-protein heterogeneous network is constructed. Then a bidirectional random walk with pruning algorithm is adopted in this heterogeneous network to predict potential DPIs. Next, the predicted DPIs are combined with the chemical fingerprint similarity of drugs and amino acid sequence similarity of proteins to construct the complete information network. The bidirectional random walk with pruning algorithm is applied in the new network to obtain the final prediction results until it converges. Experimental results show that BRWCP is superior to several state-of-the-art DPI prediction methods, and case studies further confirm its ability to tap potential drug-protein interactions. AVAILABILITY: The code of BRWCP is available at https://github.com/lyfdomain/BRWCP. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

13.
Mol Cells ; 45(9): 649-659, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36058890

RESUMO

A long-term energy nutritional imbalance fundamentally causes the development of obesity and associated fat accumulation. Lysosomes, as nutrient-sensing and lipophagy centers, critically control cellular lipid catabolism in response to nutrient deprivation. However, whether lysosome activity is directly involved in nutrient-induced fat accumulation remains unclear. In this study, worm fat accumulation was induced by 1 mM glucose or 0.02 mM palmitic acid supplementation. Along with the elevation of fat accumulation, lysosomal number and acidification were also increased, suggesting that lysosome activity might be correlated with nutrient-induced fat deposition in Caenorhabditis elegans. Furthermore, treatments with the lysosomal inhibitors chloroquine and leupeptin significantly reduced basal and nutrient-induced fat accumulation in C. elegans. The knockdown of hlh-30, which is a critical gene in lysosomal biogenesis, also resulted in worm fat loss. Finally, the mutation of aak-2, daf-15, and rsks-1 showed that mTORC1 (mechanistic target of rapamycin complex-1) signaling mediated the effects of lysosomes on basal and nutrient-induced fat accumulation in C. elegans. Overall, this study reveals the previously undescribed role of lysosomes in overnutrition sensing, suggesting a new strategy for controlling body fat accumulation.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Tecido Adiposo/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Lisossomos/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Nutrientes
14.
Biomed Pharmacother ; 154: 113622, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36081291

RESUMO

Osteoclasts play an important role in maintaining the relative stability of bone mass. Abnormal number and function of osteoclasts are closely related to osteoporosis and osteolytic diseases. Thiaplakortone B (TPB), a natural compound derived from the Great Barrier Reef sponge Plakortis lita, has been reported to inhibit the growth of the malaria parasite, Plasmodium falciparum, but its effect on osteoclastogenesis has not been previously investigated. In our study, we found that TPB suppresses the receptor activator of nuclear factor-κB (NF-κB) ligand (RANKL)-induced osteoclast formation and resorption activity by tartrate-resistant acid phosphatase (TRAcP) staining, immunofluorescence staining of F-actin belts and hydroxyapatite resorption assay. Furthermore, using quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting analysis, we discovered that TPB inhibits osteoclast-specific genes and proteins expression. Mechanistically, TPB blocks multiple upstream pathways including calcium oscillation, NF-κB, mitogen-activated protein kinase (MAPK) and nuclear factor of activated T cells 1(NFATc1) signaling pathways. In vivo, TPB could dampen bone loss in an ovariectomy (OVX) mouse model by micro-CT assessment and histological staining. Therefore, TPB may serve as a potential therapeutic candidate for the treatment of osteoporosis and osteolysis.


Assuntos
NF-kappa B , Osteoporose , Animais , Sinalização do Cálcio , Diferenciação Celular , Feminino , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Fatores de Transcrição NFATC/metabolismo , Osteoclastos , Osteogênese , Osteoporose/patologia , Ovariectomia , Ligante RANK/metabolismo
15.
Sci Rep ; 12(1): 15308, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36096934

RESUMO

Thermal loading is an important factor that could lead to the weakening and deterioration of rock materials. Understanding the thermal properties of rocks and their evolution under different high temperatures is important in the post-fire-hazard evaluation and cultural heritage conservation. Yet it is challenging to understand the evolution of thermally-induced changes in rock properties and to quantitatively study degrees of thermal damage when samples are limited. This study investigates the effects of high temperatures (i.e., 200 °C, 400 °C, 600 °C, 800 °C, and 1000 °C) on a dolomitic marble using combined mesoscopic and macroscopic testing techniques. The test results show that increasing marble temperature led to a deterioration of physical properties (i.e., increasing open porosity and weight loss; but decreasing P-wave velocity) and mechanical properties (i.e., increasing axial strain corresponding with the peak stress; but decreasing uniaxial compressive strength, Young's modulus, and brittleness). There existed a threshold temperature of 600 °C, which marks different thermal damage mechanisms. Below the threshold, the rock deterioration was mainly caused by physical changes such as crack propagation and grain breakage, which can be characterized by mesoscopic parameters (i.e., linear crack density and mineral grain size distribution). On the contrary, when the temperature was higher than the threshold, the deterioration was caused by chemical changes, including mineral decomposition and re-crystallization, which was indicated by the changes in mineral compositions and relative atomic mass calculation. Based on the experimental results (e.g., mineralogical and physico-mechanical changes) and obtained relationships between the parameters in mesoscale and macroscale, a novel scheme for thermal damage evaluation is proposed to estimate thermally-induced changes in macroscopic parameters (e.g., Young's modulus) based on the corresponding mesoscopic parameters (e.g., particle size distribution and linear crack density).

16.
mSystems ; : e0042222, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36102532

RESUMO

Recent studies have reported that some rumen microbes are heritable. However, it is necessary to clarify the functions and specific contributions of the heritable rumen microbes to cattle phenotypes (microbiability) in comparison with those that are nonheritable. This study aimed to identify the distribution and predicted functions of heritable and nonheritable bacterial taxa at species level in the rumen of dairy cows and their respective contributions to energy-corrected milk yield, protein content and yield, and fat content and yield in milk. Thirty-two heritable and 674 nonheritable bacterial taxa were identified at species level, and the functional analysis revealed that predicted microbial functions for both groups were mainly enriched for energy, amino acid, and ribonucleotide metabolism. The mean microbiability (to reflect a single taxon's contribution) of heritable bacteria was found to range from 0.16% to 0.33% for the different milk traits, whereas the range for nonheritable bacteria was 0.03% to 0.06%. These findings suggest a strong contribution by host genetics in shaping the rumen microbiota, which contribute significantly to milk production traits. Therefore, there is an opportunity to further improve milk production traits through attention to host genetics and the interaction with the rumen microbiota. IMPORTANCE Rumen bacteria produce volatile fatty acids which exert a far-reaching influence on hepatic metabolism, mammary gland metabolism, and animal production. In the current study, 32 heritable and 674 nonheritable bacterial taxa at species level were identified, and shown to have different microbiability (overall community contribution) and mean microbiability (the average of a single taxon's contribution) for lactation performance. The predicted functions of heritable and nonheritable bacterial taxa also differed, suggesting that targeted nutritional and genetic breeding approaches could be used to manipulate them to improve dairy cow performance.

17.
Psychol Res Behav Manag ; 15: 2331-2341, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36046254

RESUMO

Purpose: An individual's willingness to report is largely related to whether he or she is a direct victim. This study takes two scenarios of whether medical insurance fraud results in a direct loss of personal benefit and explores the differences in individuals' willingness to report and influencing factors in the two scenarios. Methods: In this study, questionnaires were used and participants were selected from 571 individuals in eastern, central, and western China. Analysis was performed using descriptive statistics and logistic regression models. Results: 51.0% of individuals were willing to report when no direct loss of personal benefit was caused, and conversely, 78.3% of individuals were willing to report when direct loss of personal benefit was caused. The factors influencing the attitude dimension of individuals toward whistleblowing behavior were consistent in the two scenarios. In contrast, there were significant differences among the influences in the perceived behavioral control, consequence perception, and subjective norm dimensions. Conclusion: There were significant differences in the willingness of individuals to report medical insurance fraud and the factors influencing it in both scenarios. The most significantly influencing factor difference was perceived behavioral control, a dimension that had an effect only when it did not result in a direct loss of personal benefit. When an individual's direct interests are at stake, the individual's fear for his or her safety is not a deterrent to his or her willingness to report. And when there is no loss of direct personal benefit, individuals care more about government measures to protect whistleblowers. There are differences in the subjects that influence individuals' willingness to report in the two scenarios. The factors influencing the attitude dimension are the same in both scenarios, and the more supportive the attitude toward the whistleblower, the stronger the individual's willingness to report will be.

18.
Artigo em Inglês | MEDLINE | ID: mdl-36048979

RESUMO

With the increasing penetration of the Internet of things (IoT) into people's lives, the limitations of traditional medical systems are emerging. First, the typical way of handling sensitive information can easily lead to privacy disclosure. Second, the medical system is relatively isolated. It is difficult for one medical system to share data with another, and the scope of users' activities is limited within the system boundary. To solve these two problems, we propose a new privacy-preserving medical data-sharing scheme by introducing the authorization mechanism and attribute-based encryption (ABE) based on blockchain, which breaks system boundaries and realizes data sharing among several medical institutions. ABE is used to realize scalable access control. In addition, doctors can share their knowledge to diagnose users by introducing many-to-many matching, which means that patients' health data can be represented by multiple keywords and doctors' expertise can be represented by multiple interests. We provide the correctness and security analysis of our scheme and implement a prototype tool on Ethereum. The experimental results show that our scheme solves the contradiction between the privacy preservation of medical data and the necessity of data sharing.

19.
Annu Int Conf IEEE Eng Med Biol Soc ; 2022: 1371-1374, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36085955

RESUMO

Mental health disorders, such as depression, affect a large and growing number of populations worldwide, and they may cause severe emotional, behavioral and physical health problems if left untreated. As depression affects a patient's speech characteristics, recent studies have proposed to leverage deep-learning-powered speech analysis models for depression diagnosis, which often require centralized learning on the collected voice data. However, this centralized training requiring data to be stored at a server raises the risks of severe voice data breaches, and people may not be willing to share their speech data with third parties due to privacy concerns. To address these issues, in this paper, we demonstrate for the first time that speech-based depression diagnosis models can be trained in a privacy-preserving way using federated learning, which enables collaborative model training while keeping the private speech data decentralized on clients' devices. To ensure the model's robustness under attacks, we also integrate different FL defenses into the system, such as norm bounding, differential privacy, and secure aggregation mechanisms. Extensive experiments under various FL settings on the DAIC-WOZ dataset show that our FL model can achieve high performance without sacrificing much utility compared with centralized-learning approaches while ensuring users' speech data privacy. Clinical Relevance- The experiments were conducted on publicly available clinical datasets. No humans or animals were involved.


Assuntos
Privacidade , Fala , Depressão/diagnóstico , Humanos , Aprendizagem
20.
Annu Int Conf IEEE Eng Med Biol Soc ; 2022: 1362-1365, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36086432

RESUMO

As the most common neurodegenerative disease among older adults, Alzheimer's disease (AD) would lead to loss of memory, impaired language and judgment, gait disorders, and other cognitive deficits severe enough to interfere with daily activities and significantly diminish quality of life. Recent research has shown promising results in automatic AD diagnosis via speech, leveraging the advances of deep learning in the audio domain. However, most existing studies rely on a centralized learning framework which requires subjects' voice data to be gathered to a central server, raising severe privacy concerns. To resolve this, in this paper, we propose the first federated-learning-based approach for achieving automatic AD diagnosis via spontaneous speech analysis while ensuring the subjects' data privacy. Extensive experiments under various federated learning settings on the ADReSS challenge dataset show that the proposed model can achieve high accuracy for AD detection while achieving privacy preservation. To ensure fairness of the model performance across clients in federated settings, we further deploy fair aggregation mechanisms, particularly q-FEDAvg and q-FEDSgd, which greatly reduces the algorithmic biases due to the data heterogeneity among the clients. Clinical Relevance -The experiments were conducted on publicly available clinical datasets. No humans or animals were involved.


Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Doença de Alzheimer/diagnóstico , Humanos , Privacidade , Qualidade de Vida , Fala
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