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1.
Regen Biomater ; 9: rbac003, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35668921

RESUMO

Titanium alloy has been widely used in orthopedic surgeries as bone defect filling. However, the regeneration of high-quality new bones is limited due to the pro-inflammatory microenvironment around implants, resulting in a high occurrence rate of implant loosening or failure in osteological therapy. In this study, extracellular matrix-mimetic polysaccharide hydrogel co-delivering BMP-2 and interleukin (IL)-4 was composited with 3D printed titanium alloy to promote the osseointegration and regulate macrophage response to create a pro-healing microenvironment in bone defect. Notably, it is discovered from the bioinformatics data that IL-4 and BMP-2 could affect each other through multiple signal pathways to achieve a synergistic effect toward osteogenesis. The composite scaffold significantly promoted the osteoblast differentiation and proliferation of human bone marrow mesenchyme stem cells (hBMSCs). The repair of large-scale femur defect in rat indicated that the dual-cytokine-delivered composite scaffold could manipulate a lower inflammatory level in situ by polarizing macrophages to M2 phenotype, resulting in superior efficacy of mature new bone regeneration over the treatment of native titanium alloy or that with an individual cytokine. Collectively, this work highlights the importance of M2-type macrophages-enriched immune-environment in bone healing. The biomimetic hydrogel-metal implant composite is a versatile and advanced scaffold for accelerating in vivo bone regeneration, holding great promise in treating orthopedic diseases.

2.
Comput Intell Neurosci ; 2022: 6569279, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35685137

RESUMO

In order to improve the effect of online English teaching in the context of the epidemic, this paper combines intelligent feature recognition technology to carry out an online English teaching system in the context of the epidemic and greatly reduces the number of variants by selecting mutation operators with excellent performance. Moreover, in this paper, the mutation adequacy and the number of mutation operators are regarded as two objective functions, and the selection problem of mutation operators is generated into a two-stage optimization problem, and the above problems are solved by a genetic algorithm. In addition, this paper sorts the mutation branches and preferentially covers the mutation branches of the mutants corresponding to the mutation operators with higher mutation scores. The experimental study shows that the online English teaching system based on intelligent feature recognition technology proposed in this paper meets the actual needs of online English teaching in the context of the epidemic.


Assuntos
Algoritmos , Sistemas On-Line , Mutação , Tecnologia
3.
ACS Omega ; 7(22): 18745-18751, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35694476

RESUMO

Pentacyclic triterpenoids are considered to be the potential HMGB1 inhibitors, but due to the limited number of hydrogen bond donors and the number of rotatable bonds in the rigid skeletons, their further chemical biology research with this target was restricted. To improve these profiles, microbial-catalyzed Baeyer-Villiger oxidation of the primary ursane and oleanane-type triterpenoids including uvaol (1), erythrodiol (2), oleanolic acid (3), and ursolic acid (4) was performed by Streptomyces olivaceus CICC 23628. As a result, ten new and one known A-ring cleaved metabolites were obtained and the possible biogenetic pathways were also discussed based on the HPLC-MS analysis. Furthermore, the direct interactions between compounds 1d, 2b, and HMGB1 were observed by the biolayer interferometry technique. Molecular docking revealed that the newly introduced vicinal diol at C-4, C-24, and the hydroxyl group at C-21 of compound 1d are crucial for binding with HMGB1. The cellular assay showed that co-treatment of 1d could significantly block HMGB1-activated nitric oxide release with an IC50 value of 9.37 µM on RAW 264.7 cells. Altogether, our research provides some insights into 3,4-seco-triterpenes as potential anti-inflammatory candidates for the discovery of novel HMGB1 inhibitors.

4.
Clin Sci (Lond) ; 2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35695067

RESUMO

Activation of the angiotensin II type 2 receptor (AT2R) induces diuresis and natriuresis. Increased expression or/and activity of G protein-coupled receptor kinase 4 (GRK4) or genetic variants (e.g., GRK4γ142V) cause sodium retention and hypertension. Whether GRK4 plays a role in the regulation of AT2R in the kidney remains unknown. In this study, we found that spontaneously hypertensive rats (SHRs) had increased AT2R phosphorylation and impaired AT2R-mediated diuretic and natriuretic effects, as compared with normotensive Wistar-Kyoto (WKY) rats. The regulation by GRK4 of renal AT2R phosphorylation and function was studied in human (h) GRK4γ transgenic mice. hGRK4γ142V transgenic mice had increased renal AT2R phosphorylation and impaired AT2R-mediated natriuresis, relative to hGRK4γ wild-type (WT) littermates. These were confirmed in vitro; AT2R phosphorylation was increased and AT2R-mediated inhibition of Na+-K+-ATPase activity was decreased in hGRK4γ142V, relative to hGRK4γ WT-transfected renal proximal tubule (RPT) cells. There was a direct physical interaction between renal GRK4 and AT2R that was increased in SHRs, relative to WKY rats. Ultrasound-targeted microbubble destruction of renal GRK4 decreased the renal AT2R phosphorylation and restored the impaired AT2R-mediated diuresis and natriuresis in SHRs. In vitro studies showed that GRK4 siRNA reduced AT2R phosphorylation and reversed the impaired AT2R-mediated inhibition of Na+-K+-ATPase activity in SHR RPT cells. Our present study shows that GRK4, at least in part, impairs renal AT2R-mediated diuresis and natriuresis by increasing its phosphorylation; inhibition of GRK4 expression and/or activity may be a potential strategy to improve the renal function of AT2R.

5.
Artigo em Inglês | MEDLINE | ID: mdl-35682270

RESUMO

The demand for improving health status of Chinese residents is growing with the rapid economic development. Happiness, which could be improved by some brief, self-administered, and cost-effective interventions, is reported to be associated with mortality, longevity, and self-rated health. Therefore, it is essential to assess the effect of happiness on health in China. Using data from the Chinese General Social Survey 2017, the present study explored the effect of happiness on health among Chinese residents after controlling for demographic variables, socioeconomic factors, social relationships, locations, and insurance plan. The happiness effect across subsamples by age and resident type and the mediator role of happiness were also evaluated. Based on an ordered probit regression model, we found that the effect of happiness on health was significantly positive in full sample and all subsamples. Using a structural equation model, we demonstrated that happiness could partially mediate the relationship between socioeconomic factors, social relationships factors, and health. Our data supplement the existing literature on the relationship between happiness and health and provide evidence for policymakers and stakeholders focusing on happiness as a health strategy to improve overall societal wellbeing.


Assuntos
Felicidade , Nível de Saúde , China , Humanos , Relações Interpessoais , Fatores Socioeconômicos
6.
Front Psychol ; 13: 829037, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35651562

RESUMO

The purpose of the study is to improve the business performance of new ventures. The influence of working environment and innovation behavior on business performance based on personality psychology is studied. First, the relevant theories of new ventures are introduced, and then the structural equation model is displayed. Second, the conceptual model is constructed in response to the two influencing factors of new ventures. Finally, the influencing factors of new venture performance are extracted according to the conceptual model, and a questionnaire is designed. Statistical Product and Service Solutions software is used to analyze the questionnaire data. The results show that the proportion of new enterprise developers is from 8 to 16%, and the number of employees is <150 people. The establishment time of the surveyed enterprises is from 3 to 7 years, and the proportion of the enterprises whose establishment time is <3 years is 30.79%. Management means policies, exploratory innovation, and applicability innovation have different effects on the business performance of new ventures. Among them, the management means of managers have the greatest impact on business performance, accounting for 32.57%, followed by the applicability innovation behavior of employees, accounting for 29.47%; the exploratory innovation behavior of employees takes up 26.47%. The policy environment in the industry where the enterprise is located has the smallest impact on business performance. The results of the hypotheses show that exploratory innovation and applicability innovation do not influence each other; working environment and innovation behavior have a great influence on the performance of enterprises; the most influential factor is the management means of managers. This study provides a reference for new ventures to improve their performance based on the working environment and innovation behavior.

7.
Dalton Trans ; 51(24): 9477-9485, 2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35678299

RESUMO

Aqueous Zn-ion batteries (ZIBs) show great potential in energy storage systems because of their high theoretical capacities, high safety, low cost, and environmental friendliness. The lack of suitable cathode materials for sustaining the Zn2+ intercalation/deintercalation severely restricts their further application. Herein, calcium-intercalated birnessite MnO2 anchored on carbon nanotubes (CNTs) was designed as a cathode for ZIBs. The cathode material can be facilely produced by a simple one-pot reaction process. The external calcium-intercalated MnO2 with large layer spacing affords a fast ionic migration rate and the internal CNTs serving as a structural framework endow the electrode with better electrical conductivity. Benefiting from the larger interlayer spacing and the enhanced electrical conductivity, the CNT-CaMO cathode shows a high specific capacity of 351.8 mA h g-1 at 200 mA g-1 and a long cycle life over 6000 cycles. Besides, the H+ and Zn2+ co-intercalation storage mechanism was confirmed by ex situ XRD, SEM, and XPS analyses. This work opens up a new way to develop aqueous ZIB cathode materials with a high reversible capacity and long cycle life.

8.
J Environ Manage ; 318: 115499, 2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35717695

RESUMO

We analyzed the dynamics of pollutant emissions from wildfires in mainland China from 2001 to 2019 using MODIS fire products combined with the measurements of emission factors of different vegetation types. The biomass distribution in Mainland China has heterogeneous temporal and spatial pattern, with inter-year variations and a decreasing trend from east to west. Overall, from 2001 to 2019, biomass combustion in Mainland China reached 479.59 Tg (25.24 Tg·a-1), in which northeast, north, east, south, central, northwest, and southwest regions accounted for 20.95%, 31.14%, 8.89%, 9.06%, 3.98%, 0.33% and 25.64% of total biomass combustion, respectively. The emissions of CO, CO2, CxHy, NOx, PM2.5, TC, OC and EC were 47.30, 288.05, 12.90, 0.40, 1.43, 0.83, 0.70, and 0.12 Tg (1 Tg = 1012g), respectively. PM2.5, TC and OC emissions increased in the southwest, while all pollutant emissions declined significantly in the southern region. For particulate matter from wildfires, both the ratio of its emissions to total dust and the ratio of its concentration to atmospheric PM2.5 showed an increasing trend, implying that the relative environmental impacts of particulate emissions from wildfires may be rising. In addition, our results show that the current Chinese wildfire management has successfully reduced on average more than 80% of pollutant emissions from wildfire from 2001 to 2019 compared to the natural wildfire regime (no strict wildfire management). This research on the temporal-spatial changes of pollutant emissions from wildfires in Mainland China provides support for further exploration of wildfire impacts on regional environments, and indicates the effectiveness of Chinese current wildfire policy on the pollutant emission mitigation.

9.
Front Oncol ; 12: 798829, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35719924

RESUMO

Background: There has been a paucity of evidence examining whether preventable behavioral risk factors led to ethnic differences of gastric precancerous lesions (GPL). We aimed to investigate the ethnic disparity of associations between GPL and lifestyle factors in Mongolian and Han Chinese populations. Methods: The study included participants aged 36-75 years enrolled in the Cancer Screening Program during 2016-2017 in Hohhot and Tongliao City, Inner Mongolia. GPL was defined as the gross cascading events (i.e., gastric ulcer, atrophic gastritis, intestinal metaplasia, and dysplasia) that preceded gastric cancer. Results: A total of 61638 participants were included, of whom 6863(11·1%) were Mongolians. Alcohol consumption was positively associated with GPL risk in both ethnic groups, but the magnitude was greater in Mongolians (odds ratio (OR) 6·91, 95%CI 5·82-8·28) than in Han Chinese (OR 5·64, 95%CI 5·27-6·04), corresponding to a higher population attributable fraction (PAF) for Mongolians (53·18% vs 43·71%). Besides, the strength of the positive association between physical inactivity and GPL risk was greater among Mongolians (OR 2·02, 95%CI 1·70-2·41; OR 1·09, 95%CI 1·02-1·17 among Han Chinese) with a higher PAF. Smoking was strongly associated with GPL risk in both ethnic groups as well, but the association was more prominent among Han Chinese (OR 5·24 (1·70-2·41) for <10 cigarettes/d, 8·19 (7·48-8·97) for 11-20 cigarettes/d, 7·07 (6·40-7·81) for ≥21 cigarettes/d; the corresponding ORs were 2·96 (2·19-4·00), 6·22 (5·04-7·68), and 7·03 (5·45-9·08) among Mongolians). Lastly, our findings revealed that a significant correlation between insufficient fruits and vegetable consumption and GPL risk was only found among Mongolians (OR 1·27, 95%CI 1·04-1·56). Conclusions: Our result suggested that high-risk lifestyle factors should be reduced, particularly in Mongolians. Further studies are needed to elucidate the underlying mechanisms and to reduce health disparities in underserved ethnic groups.

10.
Ann Transl Med ; 10(10): 593, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35722363

RESUMO

Background: Non-small cell lung cancer (NSCLC) is the most common subtype of all lung cancers, and KRAS is the most common mutation in this population. Unfortunately, this subgroup remains "undruggable" with the lack of an approved targeted therapy. Selumetinib has been investigated as a secondary therapy in several trials and compared to various drug regimens. Therefore, we conducted this systematic review and network meta-analysis to determine the comparative effectiveness of this drug as compared to others in patients with late-stage and malignant NSCLC. Methods: Up to July 1, 2020, 9 databases (PubMed, Scopus, Web of Science, mRCT, ICTRP, clinicaltrials.gov, VHL, SIGLE, and Google Scholar) were searched for studies following the PICOS framework: randomized trials reporting the efficacy (rate of disease progression/lack of response) of selumetinib compared to other therapies in patients with late-stage/metastatic NSCLC. The quality of retrieved studies were assessed with the revised Cochrane risk-of-bias tool. Frequentist network meta-analysis was conducted to estimate the efficacy of selumetinib as compared to other therapies and/or placebo. Results: Out of the 163 articles yielded from the primary search, 9 studies (1,195 patients) were finally included in our systematic review. The majority of clinical cases had a performance status (PS) of 0-2, and the mean age was 62 years. The overall efficacy of selumetinib was 71.77% (95% CI: 63.24-81.45%), with selumetinib administered alone having better efficacy compared to combined therapy (65.20% vs. 74.08%). In the network analysis, selumetinib had higher efficacy compared to chemo- or immune therapy, but not significantly so. The overall SAE rate of selumetinib was 42.96% (95% CI: 34.74-53.13%), with selumetinib having a significantly better safety profile compared to combined therapy (10.49% vs. 47.38%). In the network analysis, the placebo had the best safety profile followed by selumetinib and chemo- and immune therapy. Five studies had high risk of bias, 2 had some concerns, and 2 had low risk of bias. Discussion: The efficacy of selumetinib is not superior compared to combined therapy for treating NSCLC but does have a better safety profile. Current evidence is still limited, and more robust trials are still required.

12.
Eur J Radiol ; 154: 110392, 2022 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-35679701

RESUMO

PURPOSE: To explore the clinical value of diffusional kurtosis imaging (DKI) and dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) for predicting genotypes and prognostic factors of breast cancer. MATERIALS AND METHODS: A total of 130 female patients with pathologically-confirmed breast cancer and DKI and DCE-MRI data were reviewed retrospectively. Two radiologists independently evaluated mean diffusivity (MD) and mean kurtosis (MK) for the DKI model and volume transfer constant (Ktrans), reverse rate constant (Kep), and extracellular extravascular volume ratio (Ve) for the DCE-MRI model for post-processing analyses. Receiver operating characteristic (ROC) curves were used to analyse the diagnostic efficacies. RESULTS: MK, Ktrans, and Kep values were significantly higher in the high-grade Nottingham prognostic index (NPI) group (NPI ≥ 3.4) than in the low-grade NPI group (NPI < 3.4) (p < 0.01). The Ktrans had significantly greater area under ROC curve (AUC) than Kep and MK in predicting the NPI (p = 0.038 and 0.0217, respectively). Higher Ktrans, Kep, and MK values were observed in the high Ki-67 expression (≥14%) group than in the low Ki-67 expression (<14%) group (p < 0.05). Moreover, the MK value had better diagnostic performance than the Ktrans and Kep values in identifying Ki-67 expression status (p = 0.0097 and 0.0008, respectively). The combined model (MD + MK + Ktrans + Ve) had a significantly higher AUC than the single parameters for differentiating between luminal A/B and non-luminal subtypes (p = 0.003, < 0.001, 0.001, and < 0.001, respectively). The Human epidermal growth factor receptor 2-positive group had higher MD and Ve values than the other subtype groups (p < 0.05), and the Ve had a sensitivity of 100%. Moreover, the Ve AUC was significantly higher than that for MD in the identification of the triple-negative subtype (p = 0.048). CONCLUSION: Ktrans of DCE-MRI and MK of DKI demonstrated good diagnostic performance in predicting the prognostic factors of breast cancer. Additionally, the combination of the DCE-MRI and DKI models can improve the efficiency of predicting breast cancer genotypes.

13.
Artigo em Inglês | MEDLINE | ID: mdl-35711498

RESUMO

Objective: To compare of the efficacy and safety of neuroendoscopic endonasal transsphenoidal surgeries and intracranial endoscopic pterional approach in resection of tuberculum sellae meningioma. Methods: From January 2014 to June 2021, 60 patients with tuberculum sellae meningioma diagnosed and treated in our hospital were enrolled and randomly divided into study group and control group. The tuberculum sellae meningioma was removed by neuroendoscopic endonasal transsphenoidal surgeries in the study group, while the intracranial endoscopic pterional approach was used in the control group. The chi-square test was used to compare the differences of tumor complete resection rate, visual acuity improvement rate, total effective rate at 3 months after operation, and adverse reactions between the two groups. Results: The clinical characteristics of the two groups were comparable (P > 0.05). After surgical treatment, the complete resection rate in the study group was higher than that in the control group (93.3% vs 70.0%), and the difference was statistically significant (P=0.020). After treatment, the visual acuity improvement rate of the study group was 83.3% (25/30), which was significantly higher than that of the control group (60.0%, 18/30), and the difference was statistically significant (χ 2 = 4.022, P=0.045). After surgical treatment, the total effective rate at 3 months after operation was higher in the study group than in the control group (96.7% vs 83.3%), with statistical significance (P=0.041). There was no significant difference in postoperative adverse reactions between the study group and control group (33.3% vs 30.0%, P=0.781). Conclusion: The neuroendoscopic endonasal transsphenoidal surgeries has significant efficacy and can significantly improve the visual acuity of patients without increasing adverse reactions, which is worthy of clinical promotion.

14.
Mol Ecol ; 2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35712997

RESUMO

Populus species have long been used as model organisms to study the adaptability of trees and the evolution of sex chromosomes. As a species belonging to the section Populus and limited to tropical areas, the P. qiongdaoensis genome contains important information for tropical poplar studies and protection. Here, we reported a chromosome-level genome assembly and annotation of a female P. qiongdaoensis. The gene family clustering, positive selection detection, and historical reconstruction of population dynamics revealed the tropical adaptation of P. qiongdaoensis, and showed the convergent evolution with another tropical poplar, P. ilicifolia at the molecular level, especially on some functional genes (such as PIF3 and PIL1). In addition, we also identified a ZW sex determination system on chromosome 19 of P. qiongdaoensis, and inferred that it seems to have a similar sex determination mechanism to other poplars, controlled by a type-A cytokinin response regulator (RR) gene. However, comparison and phylogenetic analysis of the sex determination regions confirmed a cryptic sex turnover event in the section Populus, which may be caused by the translocation and duplication of the RR gene driven by Helitron-like transposable elements. Our study provides new insights into the environmental adaptation and sex chromosome evolution of poplars, and emphasizes the importance of using long read sequencing in ecological and evolutionary inferences of plants.

15.
Transbound Emerg Dis ; 2022 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-35717667

RESUMO

The Chinese IBDV novel variant (nvIBDV), belonging to the genotype A2dB1b, an emerging pathotype that can cause subclinical disease with severe, prolonged immunosuppression, poses a new threat to the poultry industry. The process of the global origin, evolution and transmission dynamics of nvIBDV, however, is poorly understood. In this study, phylogenetic trees, site substitutions of amino acid (aa) and highly accurate protein structure modeling, selection pressure, evolutionary and transmission dynamics of nvIBDV was analyzed. Interestingly, nvIBDV was classified into the same genogroup with the early US antigenic variants (avIBDV) but in a new lineage with a markedly different and specific pattern of 17 aa-residual substitutions: 13 in VP2 (77D, 213N, 221K, 222T, 249K, 252I, 253Q, 254N, 284A, 286I, 299S, 318D and 323E) and 4 in VP1 (141I, 163V, 240E and 508K). Importantly, the aa-residues 299S and 163V may play a key role in cell binding and polymerase activity, respectively. The effective population size of the circulating avIBDV experienced two growth phases respectively in the years 1999-2007 (in North America) and 2015-2021 (in Asia), which is consistent with the observed trend of the epidemic outbreaks. The most recent common ancestor (tMRCA) of avIBDV most first originated in the USA and was dated around the 1970s. After its emergence, the ancestor virus of this group probably spread to China around the 1990s and the variants experienced a long-term latent circulation with the accumulation of several critical aa-residue mutations in VP2 until reemerging in 2016. At present, central China has become the epicenter of nvIBDV spread to other parts of China and Asian countries. Importantly, a strong correlation seems to exist between the transmission patterns of virus and the flow of commercial trade of live poultry and products. These findings provide important insights into the origin, evolution and transmission of the nvIBDV and will assist in the development of programs for control strategies for these emerging viruses. This article is protected by copyright. All rights reserved.

16.
Viruses ; 14(5)2022 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-35632628

RESUMO

A human betaretrovirus (HBRV) has been linked with the autoimmune liver disease, primary biliary cholangitis (PBC), and various cancers, including breast cancer and lymphoma. HBRV is closely related to the mouse mammary tumor virus, and represents the only exogenous betaretrovirus characterized in humans to date. Evidence of infection in patients with PBC has been demonstrated through the identification of proviral integration sites in lymphoid tissue, the major reservoir of infection, as well as biliary epithelium, which is the site of the disease process. Accordingly, we tested the hypothesis that patients with PBC harbor a transmissible betaretrovirus by co-cultivation of PBC patients' lymph node homogenates with the HS578T breast cancer line. Because of the low level of HBRV replication, betaretrovirus producing cells were subcloned to optimize viral isolation and production. Evidence of infection was provided by electron microscopy, RT-PCR, in situ hybridization, cloning of the HBRV proviral genome and demonstration of more than 3400 integration sites. Further evidence of viral transmissibility was demonstrated by infection of biliary epithelial cells. While HBRV did not show a preference for integration proximal to specific genomic features, analyses of common insertion sites revealed evidence of integration proximal to cancer associated genes. These studies demonstrate the isolation of HBRV with features similar to mouse mammary tumor virus and confirm that patients with PBC display evidence of a transmissible viral infection.


Assuntos
Betaretrovirus , Neoplasias da Mama , Cirrose Hepática Biliar , Animais , Feminino , Humanos , Cirrose Hepática Biliar/etiologia , Vírus do Tumor Mamário do Camundongo/genética , Camundongos , Provírus/genética
17.
J Appl Clin Med Phys ; : e13656, 2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35635548

RESUMO

PURPOSE: To quantify the influence of beam optics asymmetric distribution on dose. METHODS: Nine reference cubic targets and corresponding plans with modulation widths (M) of 3, 6, and 9 cm and with center depths (CDs) of 6, 12, and 24 cm were generated by the treatment planning system (TPS). The Monte Carlo code FLUKA was used for simulating the dose distribution from the aforementioned original plans and the dose perturbation by varying ±5%, ±15%, ±20%, ±25%, and ±40% in spot full width half maximum to the X-direction while keeping consistent in the Y-direction. The dosimetric comparisons in dose deviation, γ-index analysis, lateral penumbra, and flatness were evaluated. RESULTS: The largest 3D absolute mean deviation was 15.0% ± 20.9% (mean ± standard deviation) in M3CD6, whereas with the variation from -15% to +20%, the values were below 5% for all cube plans. The lowest 2D γ-index passing rate was 80.6% with criteria of 2%-2 mm by a +40% variation in M3CD6. For the M9CD24 with a -40% variation, the maximum 1D dose deviations were 5.6% and 15.7% in the high-dose region and the edge of the radiation field, respectively. The maximum deviations of penumbra and flatness were 3.4 mm and 11.4%, respectively. CONCLUSIONS: The scenario of beam optics asymmetric showed relatively slight influence on the global dose distribution but severely affected dose on the edge of the radiation field. For scanning carbon-ion therapy facilities, beam spot lateral profile settings in TPS base data should be properly handled when beam optics asymmetry variation is over 15%.

18.
J Environ Manage ; 316: 115060, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35588672

RESUMO

To combat climate change, reducing carbon emissions from coal consumption in the power sector can be an effective strategy. We developed a price-exogenous mixed integer linear optimization model satisfying both traditional timber demand in Georgia and its neighboring states (Alabama, Florida, North Carolina, South Carolina, and Tennessee) and additional bioenergy demand to replace coal in the power plants of Georgia for 50 years, maximizing social welfare. We used Forest Inventory & Analysis unit level yield of five forest types (planted softwood, natural softwood, upland hardwood, bottomland hardwood, and mixed forest), timber demand, and price information, and developed three scenarios. In the Baseline scenario, traditional annual timber demand (152 million tons of wood) was satisfied with no coal replacement. In Scenario 1, 100% coal (7.34 million tons annually) was replaced using pulpwood only, along with traditional demand. In Scenario 2, also with traditional demand, 100% coal was replaced using pulpwood and logging residues. It would require approximately 336 and 98 thousand acres of additional annual timberland harvested in Scenario 1 and Scenario 2, respectively, compared to Baseline (1280 thousand acres). During 50 years, a total of 9.3, 10.2, and 9.6 billion tons of timber was produced in Baseline, Scenario 1, and Scenario 2, respectively. About one-third of all torrefaction plants would be located in the central region of Georgia. The net change in stand carbon was positive in all three scenarios-the highest in Baseline (1330 million tons C), followed by Scenario 2 (1261 million tons C), and the lowest in Scenario 1 (872 million tons C). About 240 million tons of carbon was avoided by using biomass instead of coal in Scenario 1 and Scenario 2. In Baseline, with continued emission from coal usage in the power plant for 50 years (285 million tons C), net carbon benefit was 1046 million tons C. Replacing 100% of coal with both pulpwood and logging residues provided a net benefit of 1501 million tons C, about 43% higher compared to baseline.


Assuntos
Carbono , Carvão Mineral , Biomassa , Florestas , Georgia , Centrais Elétricas , Programação Linear , Madeira
19.
Toxins (Basel) ; 14(5)2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-35622595

RESUMO

Silage, especially whole crop corn silage (WCCS), is an important part of ruminant diets, with its high moisture content and rich nutrient content, which can easily cause contamination by mold and their toxins, posing a great threat to ruminant production, food safety and human health. The objective of this study was to examine effects of lactic acid bacteria (LAB) Lactiplantibacillus (L.) plantarum subsp. plantarum ZA3 and Artemisia argyi (AA) on the fermentation characteristics, microbial community and mycotoxin of WCCS during 60 days (d) ensiling and subsequent 7 d aerobic exposure. The results showed that WCCS treated with LAB and AA both had lower pH value and ammonia nitrogen (NH3-N) contents, and higher lactic and acetic acids concentration compared with other groups after 60 d ensiling. In addition, for microbial communities, Acetobacter and Enterobacter were inhibited in all AA group, while higher abundance of Lactobacilli was maintained; besides, Candida, Pichia and Kazachstania abundances were decreased in both 6% and 12% AA groups. The content of five kinds of mycotoxins were all significantly lower after 7 d of aerobic exposure. As for the total flavonoid (TF), which is significantly higher in all AA treated groups, it was positively correlated with Paenibacillus, Weissella and Lactobacilli, and negatively with Acetobacter, Enterobacteria, Kazachstania and Pichia.


Assuntos
Artemisia , Lactobacillales , Microbiota , Fermentação , Humanos , Lactobacillus , Silagem/análise , Zea mays/microbiologia
20.
Food Chem Toxicol ; 165: 113142, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35595038

RESUMO

Bisphenol S (BPS) is extensively used for production of polycarbonates and other commodities, and is often detected in environment and biota. Parental BPS exposure has been reported to interfere with reproductive development of offspring, but limited information is available on its multigenerational reproductive toxicity. In our present study, zebrafish (Danio rerio) were exposed to BPS (1 and 100 µg/L) from 3 hpf to 120 dpf, and the effects on reproduction, sex steroid hormones, DNA methylation levels and gene transcription involved in steroidogenesis and DNA methylation were investigated in unexposed F1-2 offspring. The results showed that 100 µg/L BPS exposure increased DNA methylation in F1 testes, and 1 µg/L BPS led to DNA methylation in F2 ovaries. The increased DNA methylation levels led to decreased expression of steroidogenic enzymes, including cyp11a, cyp17 and 3ßhsd, which might be a main reason for the elevated plasma 17ß-estradiol and decreased testosterone levels. In addition, sex ratio indicated a female dominance trend, and reproductive capacity of male fish was severely impaired. Overall, these findings suggest that parental BPS exposure impairs reproductive development of unexposed offspring via DNA methylation and BPS-induced epigenetic modification inheritance has a long-term effect on the fitness and sustainability of fish populations.


Assuntos
Poluentes Químicos da Água , Peixe-Zebra , Animais , Feminino , Masculino , Fenóis/farmacologia , Reprodução , Sulfonas/toxicidade , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo
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