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1.
J Affect Disord ; 296: 183-188, 2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34607059

RESUMO

BACKGROUND: Evidence of an association between sleep duration and depression was inconsistent. METHODS: Adults who participated in the National Health and Nutrition Examination Survey (NHANES) from 2009 to 2016 were included. Multivariable logistic regression was used to evaluate the association between sleep duration and depression. RESULTS: Among the 25,962 participants (mean age 48.1 years; 49.2% male) in this study, 23,636 had a depression score <10 and 2,326 had a depression score ≥ 10. After adjustment for gender, age, race/ethnicity, education, marital status, and annual family income, BMI, alcohol status, and smoking status, hypertension, diabetes, dyslipidemia, work activity, and physical activity risk factors, participants who had short sleep duration had odds ratios (OR) of 1.86 (95% confidence interval 1.59, 2.17) and participants who had long sleep duration had OR of 1.49 (95% confidence interval 1.22, 1.83) for incident depression. Further analysis revealed a U-shaped association between sleep duration and incident depression. When sleep duration < 8 hours, increased sleep duration is associated with a significantly lower risk of incident depression (OR = 0.68 [95% CI 0.64, 0.71], P < 0.001). When sleep duration ≥ 8 hours, the risk of depression increased significantly with an increase in sleep duration (OR = 1.32 [95%CI 1.23, 1.41], P < 0.001). CONCLUSIONS: Sleep duration were independently associated with a higher incident depression. Not only insufficient sleep but excessive sleep also increase the risk of depression.

2.
Chemosphere ; 287(Pt 3): 132181, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34583297

RESUMO

The high toxicity of Cr-Ca compounds generated during the heat treatment of solid waste will heavily threat the environment. In this work, a kind of Ca-rich river sludge which is bound with Ca and heavy metals was combusted with kaolin under 900 °C for 3 h in a muffle to study the transformation of Cr. The effects of kaolin on Cr transformation were investigated through sequential extraction, the risk assessment of heavy metals, and constant pH leaching test, also combined with crystal phase analysis of Ca-Al-Si minerals. The experimental results showed that the formation of Ca10(SiO4)3(SO4)3Cl2 was inhibited by the addition of 10% (mass fraction) kaolin and the released Cl promoted the evaporation of target elements in priority while 30% kaolin addition further inhibited the solidification of Cr. Furthermore, the effect of NaCl and CaCO3 on the Cr solidification by kaolin were also explored by leaching procedure or XRD analysis of calcination products of their mixtures. It should be noticed that the addition of kaolin in Cr2O3-CaCO3 mixture will directly react with CaCrO4 and fixed the generated Cr2O3 into internal layered structure, preventing its re-oxidization by the free CaO. This work aims to help illustrate the Cr transformation with existence of Ca during sintering of Ca-rich solid wastes and reduce the Cr contamination in future.

3.
J Agric Food Chem ; 69(32): 9395-9406, 2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34344151

RESUMO

There are still many challenges in understanding the absorption and transport mechanism of liposomes in the gastrointestinal tract of infants, especially for liposome-coentrapped two or more substances. In this study, novel docosahexaenoic acid (DHA)-anthocyanidin-codelivery liposomes (DA-LPs) were fabricated and characterized, and their digestive and absorptive behaviors were evaluated using the in vitro infant digestive method combined with the Caco-2 cell model. The liposomal bilayer structure remained intact with the particles aggregated in simulated infant gastric fluid, while their phospholipid membrane underwent enzymatic lipolysis under simulated intestinal conditions. Compared to single substance-loaded liposomes (DHA- or anthocyanidin-loaded liposomes), the digested DA-LPs showed better cell viability, higher cellular uptake and membrane fluidity, and lower reactive oxygen species (ROS). It can be concluded that DA-LPs are promising carriers for simultaneously transporting hydrophobic and hydrophilic molecules and may be beneficial for improving nutrient absorption and alleviating intestinal stress oxidation.


Assuntos
Antocianinas , Ácidos Docosa-Hexaenoicos , Células CACO-2 , Digestão , Humanos , Lactente , Lipossomos
4.
ISA Trans ; 2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34446282

RESUMO

In this paper, we focus on the tracking problem of a dual-arm robot (DAR) with prescribed performance and unknown input backlash-like hysteresis. Considering this problem, adaptive coordinated control with actor-critic (AC) design is proposed. Motivated by the increasing control requirements, prescribed performance is imposed on the DAR system to guarantee the tracking performance. In order to improve the self-learning ability and handle the problems caused by the input backlash-like hysteresis and system uncertainty, AC learning (ACL) algorithm is introduced. Through the cost function about tracking errors, a critic network is adopted to judge the control performance. An actor network is adopted to obtain the control input based on the critic result, where the system uncertainty and unknown part of the input backlash-like hysteresis are approximated by neural networks (NNs). In addition, the system stability is proven by the Lyapunov direct method. Numerical simulation is finally conducted to further testify the validity of the proposed coordinated control with AC design for the DAR system.

5.
Environ Entomol ; 50(5): 1037-1044, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34278427

RESUMO

Black soldier fly, Hermetia illucens (L.) (Diptera: Stratiomyidae), larvae are suspected to inhibit house flies, Musca domestica (L.) (Diptera: Muscidae), seeking oviposition sites. However, the mechanisms regulating these interactions are not well known. In this study, a Y-tube olfactometer was used to determine whether black soldier fly eggs, larvae, puparia (without pupae inside), adult carcasses, or resulting frass of black soldier fly decrease attractiveness of adult house flies to an oviposition substrate (i.e., sugar and wheat bran diet, used as the control). Secondly, two symbiotic bacteria associated were isolated, identified, and tested for house fly attractiveness with a Y-tube olfactometer. Thirdly, volatile organic compounds produced by swine feed before and after black soldier fly, or house fly larval digestion were analyzed with gas chromatography-mass spectrometry (GC-MS). Results indicate feed mixed with black soldier fly larval frass, and symbiotic bacteria, Paenalcaligenes sp. associated with black soldier fly, were less attractive to house flies than the control. However, another symbiotic bacterium Lysinibacillus sp. associated with black soldier fly pupae was attractive. In total, 52 volatile organic compounds were identified from treatments previously described. Quantitative differences in volatile profiles across treatments potentially explain the mechanism regulating house fly substrate choices in the presence, or absence, of black soldier fly larvae.

6.
Comput Methods Programs Biomed ; 208: 106287, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34311416

RESUMO

BACKGROUND: Preoperative prognostic biomarkers to guide individualized therapy are still in demand in esophageal squamous cell cancer (ESCC). Some studies reported that radiomic analysis based on CT images has been successfully performed to predict individual survival in EC. The aim of this study was to assess whether combining radiomics features from primary tumor and regional lymph nodes predicts overall survival (OS) better than using single-region features only, and to investigate the incremental value of the dual-region radiomics signature. METHODS: In this retrospective study, three radiomics signatures were built from preoperative enhanced CT in a training cohort (n = 200) using LASSO Cox model. Associations between each signature and survival was assessed on a validation cohort (n = 107). Prediction accuracy for the three signatures was compared. By constructing a clinical nomogram and a radiomics-clinical nomogram, incremental prognostic value of the radiomics signature over clinicopathological factors in OS prediction was assessed in terms of discrimination, calibration, reclassification and clinical usefulness. RESULTS: The dual-region radiomic signature was an independent factor, significantly associated with OS (HR: 1.869, 95% CI: 1.347, 2.592, P = 1.82e-04), which achieved better OS (C-index: 0.611) prediction either than the single-region signature (C-index:0.594-0.604). The resulted dual-region radiomics-clinical nomogram achieved the best discriminative ability in OS prediction (C-index:0.700). Compared with the clinical nomogram, the radiomics-clinical nomogram improved the calibration and classification accuracy for OS prediction with a total net reclassification improvement (NRI) of 26.9% (P=0.008) and integrated discrimination improvement (IDI) of 6.8% (P<0.001). CONCLUSION: The dual-region radiomic signature is an independent prognostic marker and outperforms single-region signature in OS for ESCC patients. Integrating the dual-region radiomics signature and clinicopathological factors improves OS prediction.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas/diagnóstico por imagem , Neoplasias Esofágicas/diagnóstico por imagem , Humanos , Linfonodos/diagnóstico por imagem , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
7.
J Consult Clin Psychol ; 89(6): 537-550, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34264701

RESUMO

OBJECTIVE: To determine if the Transdiagnostic Intervention for Sleep and Circadian Dysfunction (TranS-C) improves functional impairment, psychiatric symptoms, and sleep and circadian functioning. METHOD: Adults diagnosed with serious mental illness (SMI) and sleep and circadian dysfunction (N = 121) were randomly allocated to TranS-C plus usual care (TranS-C + UC; n = 61; 8 individual weekly sessions) or 6 months of Usual Care followed by Delayed Treatment with TranS-C (UC-DT; n = 60). Schizophrenia (45%) and anxiety disorders (47%) were common. Blind assessments were conducted pre-treatment, post-treatment, and 6 months later (6FU). The latter two were the post-randomization points of interest. The location was Alameda County Behavioral Health Care Services (ACBHCS), a Community Mental Health Center (CMHC) in California. RESULTS: For the primary outcomes, relative to UC-DT, TranS-C + UC was associated with reduction in functional impairment (b = -3.18, p = 0.025, d = -0.58), general psychiatric symptoms (b = -5.88, p = 0.001, d = -0.64), sleep disturbance (b = -5.55, p < .0001, d = -0.96), and sleep-related impairment (b = -9.14, p < .0001, d = -0.81) from pre-treatment to post-treatment. These effects were maintained to 6-month follow-up (6FU; d = -0.42 to -0.82), except functional impairment (d = -0.37). For the secondary outcomes, relative to UC-DT, TranS-C + UC was associated with improvement in sleep efficiency and on the Sleep Health Composite score from pre-treatment to 6FU. TranS-C + UC was also associated with reduced total wake time and wake time variability from pre-treatment to post-treatment, as well as reduced hallucinations and delusions, bedtime variability, and actigraphy measured waking activity count variability from pre-treatment to 6FU. CONCLUSIONS: A novel transdiagnostic treatment, delivered within a CMHC setting, improves selected measures of functioning, symptoms of comorbid disorders, and sleep and circadian outcomes. (PsycInfo Database Record (c) 2021 APA, all rights reserved).


Assuntos
Centros Comunitários de Saúde Mental , Transtornos Mentais/terapia , Psicoterapia/métodos , Transtornos do Sono do Ritmo Circadiano/terapia , Transtornos do Sono-Vigília/terapia , Adulto , Ansiedade/terapia , Transtornos de Ansiedade/terapia , California , Feminino , Humanos , Masculino , Transtornos Mentais/complicações , Pessoa de Meia-Idade , Esquizofrenia/terapia , Sono , Transtornos do Sono do Ritmo Circadiano/complicações , Transtornos do Sono-Vigília/complicações , Resultado do Tratamento
8.
Behav Ther ; 52(4): 932-944, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34134832

RESUMO

Patient memory for the contents of treatment is staggeringly poor, and poor memory for treatment is associated with worse treatment outcome. Accordingly, the Memory Support Intervention was developed to improve patient memory for treatment as an adjunct to treatment as usual. As plans to disseminate the Memory Support Intervention are developed, it is important to have efficient, accurate methods of measuring fidelity to the intervention. However, the existing method of assessing fidelity to the Memory Support Intervention, the Memory Support Rating Scale (MSRS), is burdensome and requires trained independent-raters to spend multiple hours reviewing session recordings, which is not feasible in many routine mental health care settings. Hence, a provider-rated measure of fidelity to the MSI has been developed. The goal of this study is to examine the reliability and validity of scores on this measure-the Memory Support Treatment Provider Checklist. A sample of Memory Support Treatment Provider Checklists (N = 319) were completed by providers (N = 8) treating adults with depression (N = 84). Three metrics of the Memory Support Treatment Provider Checklist were evaluated: (a) the internal consistency and structural validity using confirmatory factor analysis based on prior research on the MSRS and the Memory Support Intervention, (b) construct validity, and (c) predictive validity. Results indicate that the Memory Support Treatment Provider Checklist yields reliable and valid scores of fidelity to the Memory Support Intervention. Overall, this checklist offers a viable, brief method of evaluating fidelity to the Memory Support Intervention.


Assuntos
Lista de Checagem , Projetos de Pesquisa , Adulto , Humanos , Reprodutibilidade dos Testes
9.
J Natl Med Assoc ; 2021 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-34158171

RESUMO

BACKGROUND: National data indicate low intentions for COVID-19 vaccination among a substantial minority of Black Americans, and disproportionately lower vaccination rates among Black Americans than White Americans. METHODS: A total of 207 of the 318 Black participants (65%) in the RAND American Life Panel, a nationally representative internet panel, were surveyed about COVID-19 vaccine intentions in November-December 2020. Participants' census tracts were geocoded using the Centers for Disease Control and Prevention's Social Vulnerability Index. RESULTS: Overall, 35% agreed or strongly agreed that they would not get a COVID-19 vaccine, 40% agreed or strongly agreed that they would get vaccinated, and 25% reported "don't know." Significant multivariable predictors of not wanting to get vaccinated included high mistrust of the vaccine itself (e.g., concerns about harm and side effects), OR (95% CI) = 2.2 (1.2-3.9), p = .007, and weak subjective norms for vaccination in one's close social network, OR (95% CI) = 0.6 (0.4-0.7), p < .001. Residence in an area of higher socioeconomic vulnerability was a marginally significant predictor, OR (95% CI) = 3.1 (0.9-11.0), p = .08. CONCLUSIONS: High mistrust around COVID-19 vaccines may lower vaccine confidence. Social network members' attitudes can be influential in encouraging vaccination. Public health communications could use transparent and clear messaging on safety and efficacy, and acknowledge historical and ongoing discrimination and racism as understandable reasons for low confidence in COVID-19 vaccines. Future research is needed to consider vaccine access challenges in tandem with mistrust as contributing to low vaccination rates across health conditions.

10.
Water Res ; 201: 117310, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34119967

RESUMO

Humic-like acids (HAs) are abundant in sewage sludge but mainly bonded with solids. Thus, their influences are often neglected in conventional digestion processes. Currently thermal hydrolysis pretreatment (THP) has been widely adopted in sludge anaerobic digestion (AD) to enhance hydrolysis of complex matters and further to improve methane production. However, the impacts of enhanced release of HAs and the mechanisms involved are not well understood and need to be further investigated because the substantial amounts of HAs present in AD could severely threaten the sludge AD processes. Results in the present study indicated that the concentration of soluble HAs in sludge was elevated by 90 times due to the THP, from 8 mg/L in raw sludge to 727 mg/L in the pretreated sludge hydrolyzed at 180 °C. Moreover, the structural characteristics of soluble HAs, including aromatic condensation degree, elemental composition and functional group, also showed substantial differences with the increased temperature of the THP. Furthermore, the release of HAs presented significant influences on sludge digestion. Acidification rate was inhibited by over 50% with 0.4 g/L of HAs, whereas methanogenesis was improved by nearly 200% with 0.8 g/L HAs and inhibited about 50% with 2.0 g/L. The activities of proteinase and co-enzyme F420 were decreased by 20% and increased by 19%, respectively, under HAs stress at 0.6 g/L for 5 days. Moreover, molecular structural changes of soluble HAs also contributed to the influences. Especially, the E4/E6 value representing the degree of HAs aromatic condensation and C/N ratio of soluble HAs were closely correlated with their inhibition degree to sludge hydrolysis. The findings of this study demonstrate that the influences of HAs are evident and also vary to the different steps of anaerobic digestion processes, which shall not be negligible during the sludge digestion that is with THP. Due to the rate-limiting step was methanogenesis in the AD process of pretreated sludge by thermal hydrolysis, HAs concentration was recommended at low level, for example around 1.0 g/L, to accelerate or not limit methanogenesis.


Assuntos
Substâncias Húmicas , Esgotos , Anaerobiose , Hidrólise , Metano , Eliminação de Resíduos Líquidos
11.
Mol Biol Evol ; 38(9): 3649-3663, 2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-33944941

RESUMO

Obligate scavenging on the dead and decaying animal matter is a rare dietary specialization that in extant vertebrates is restricted to vultures. These birds perform essential ecological services, yet many vulture species have undergone recent steep population declines and are now endangered. To test for molecular adaptations underlying obligate scavenging in vultures, and to assess whether genomic features might have contributed to their population declines, we generated high-quality genomes of the Himalayan and bearded vultures, representing both independent origins of scavenging within the Accipitridae, alongside a sister taxon, the upland buzzard. By comparing our data to published sequences from other birds, we show that the evolution of obligate scavenging in vultures has been accompanied by widespread positive selection acting on genes underlying gastric acid production, and immunity. Moreover, we find evidence of parallel molecular evolution, with amino acid replacements shared among divergent lineages of these scavengers. Our genome-wide screens also reveal that both the Himalayan and bearded vultures exhibit low levels of genetic diversity, equating to around a half of the mean genetic diversity of other bird genomes examined. However, demographic reconstructions indicate that population declines began at around the Last Glacial Maximum, predating the well-documented dramatic declines of the past three decades. Taken together, our genomic analyses imply that vultures harbor unique adaptations for processing carrion, but that modern populations are genetically depauperate and thus especially vulnerable to further genetic erosion through anthropogenic activities.

12.
J Clin Sleep Med ; 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33969821

RESUMO

STUDY OBJECTIVES: Black individuals and individuals of low socioeconomic status are at increased risk for obstructive sleep apnea (OSA). The Berlin Questionnaire is one of the most widely used screening tools for OSA; however, there is limited research on its diagnostic accuracy in low-income, Black populations. METHODS: This study analyzed data from an ongoing study taking place among a cohort from two predominantly Black neighborhoods in Pittsburgh, PA (96.3% Black, 79.6% female). The sample included 269 individuals without a prior diagnosis of OSA who completed the Berlin Questionnaire and also participated in a home sleep apnea test (HSAT). An apnea-hypopnea index (AHI) ≥ 15 was used to identify individuals with moderate or severe OSA. RESULTS: 19.3% of individuals met criteria for moderate to severe OSA based on HSAT, while 31.2% of participants screened as high risk for OSA based on the overall Berlin index. Using AHI>=15 as the reference standard, the Berlin Questionnaire had a sensitivity of 46.2%, specificity of 72.4%, positive predictive value (PPV) of 28.6%, and negative predictive value of 84.9% among this sample. Analyses stratified by sex suggested that the Berlin Questionnaire had better diagnostic validity in women than men. CONCLUSIONS: The Berlin Questionnaire has lower sensitivity and PPV in our sample than those observed in general population samples. The measure performed better among women, though a higher proportion of men fell into the moderate or severe OSA range based on the HSAT. Given the significant downstream consequences of OSA, utilizing screening tools that better detect OSA in Black communities is key.

13.
Sleep ; 44(10)2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-33884430

RESUMO

STUDY OBJECTIVES: This study examined longitudinal associations of sleep problems with alcohol and cannabis use across six annual waves of data from adolescence to emerging adulthood. METHODS: Participants were 3,265 youth from California (ages 16-22 across waves). At each wave, past-month alcohol use and cannabis use, mental health, and several dimensions of sleep health (i.e. social jetlag, bedtimes, time in bed, trouble sleeping) were assessed via questionnaire. Parallel process latent growth models examined the association between sleep and alcohol or cannabis use trajectories and the role of mental health in contributing to such trajectories. RESULTS: Smaller declines in social jetlag (r = 0.11, p = 0.04), increases in trouble sleeping (r = 0.18, p < 0.01), and later weekday (r = 0.16, p < 0.01) and weekend bedtimes (r = 0.25, p < 0.01) were associated with increases in likelihood of alcohol use over time. Declines in weekend TIB (r = -0.13, p = 0.03), as well as increases in weekday TIB (r = 0.11, p = 0.04) and later weekday (r = 0.18, p < 0.01) and weekend bedtime (r = 0.24, p < 0.01), were associated with increases in likelihood of cannabis use over time. Most associations remained significant after controlling for time-varying mental health symptoms. CONCLUSIONS: Trajectories of sleep health were associated with trajectories of alcohol and cannabis use during late adolescence to emerging adulthood. Improving sleep is an important target for intervention efforts to reduce the risk of substance use during this critical developmental transition.

14.
Annu Rev Food Sci Technol ; 12: 259-286, 2021 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-33770470

RESUMO

Thermal processing is one of the most important processing methods in the food industry. However, many studies have revealed that thermal processing can have detrimental effects on the nutritional and functional properties of foods because of the complex interactions among food components. Proteins are essential nutrients for humans, and changes in the structure and nutritional properties of proteins can substantially impact the biological effects of foods. This review focuses on the interactions among proteins, sugars, and lipids during thermal food processing and the effects of these interactions on the structure, nutritional value, and biological effects of proteins. In particular, the negative effects of modified proteins on human health and strategies for mitigating these detrimental effects from two perspectives, namely, reducing the formation of modified proteins during thermal processing and dietary intervention in vivo, are discussed.

15.
Virulence ; 12(1): 415-429, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33459158

RESUMO

Cronobacter sakazakii, an emerging opportunistic pathogen, is implicated in severe foodborne outbreak infections in premature and full-term infants. Generally, acid tolerance is vital for the pathogenesis of foodborne pathogens; however, its role in C. sakazakii virulence remains largely unknown. To screen out acid-tolerance determinants from transposon mutants, anovel counterselection method using gentamicin and acid was developed. Using the counterselection method and growth assay, we screened several acid-sensitive mutants and found that nlpD encodes an acid-resistance factor in C. sakazakii.  Compared to the wild-type strain, the nlpD mutant exhibited attenuated virulence in a rat model. Using macrophage THP-1 cells and a pH probe, we verified that nlpD enables bacteria to resist macrophages by resisting acidification. Finally, we confirmed that nlpD maintains C. sakazakii membrane integrity in acid using propidium iodide permeabilization assays via flow cytometry. Our results confirm that nlpD is a novel virulence factor that permits C. sakazakii to survive under acid stress conditions. Considering that NlpD is a conserved lipoprotein located in the bacterial outer membrane, NlpD could be used as a target for drug development.


Assuntos
Proteínas da Membrana Bacteriana Externa/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Cronobacter sakazakii/genética , Cronobacter sakazakii/patogenicidade , Regulação Bacteriana da Expressão Gênica , Lipoproteínas/genética , Lipoproteínas/metabolismo , Macrófagos/microbiologia , Ácidos/farmacologia , Animais , Proteínas da Membrana Bacteriana Externa/genética , Cronobacter sakazakii/efeitos dos fármacos , Ratos , Fatores de Virulência/genética
16.
Cancer Nurs ; 44(4): 272-280, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32022780

RESUMO

BACKGROUND: Lung cancer has become the leading cause of cancer-related deaths in China, and patients often experience multiple symptoms and substantial discomfort. Understanding and managing concurrent symptoms of patients with lung cancer are crucial during perichemotherapy. OBJECTIVE: To determine the types and components of symptom clusters according to the severity dimension and to understand how they change over time during perichemotherapy in a homogeneous population of patients with lung cancer. METHODS: Patients were recruited using convenience sampling. The Chinese version of the MD Anderson Symptom Inventory and the revised lung cancer module were used to measure multiple symptoms at the following 3 separate points: 2 weeks before chemotherapy (T1), chemotherapy cycle 1 (T2), and chemotherapy cycle 4 (T3). Symptom clusters were identified by exploratory factor analysis. RESULTS: A total of 144 patients with non-small cell lung cancer participated in the study. Six symptom clusters were identified at the 3 time points. Among the 6 symptom clusters, 3 symptom clusters remained stable at all time points, and differences were found in symptom clusters before and after chemotherapy. CONCLUSIONS: Symptom clusters can change during perichemotherapy, showing some stability and differences over time. IMPLICATIONS FOR PRACTICE: An improved understanding of symptom cluster trajectories in patients with lung cancer may facilitate effective assessment, prevention, and management of multiple concurrent symptoms. These findings will help clinicians to develop predictive interventions and reduce the symptom burden of patients undergoing chemotherapy.

17.
IEEE Trans Neural Netw Learn Syst ; 32(5): 2054-2065, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32554331

RESUMO

In this article, we study cooperative multiagent systems (MASs) with multiple tasks by using reinforcement learning (RL)-based algorithms. The target for a single-agent RL system is represented by its scalar reward signals. However, for an MAS with multiple cooperative tasks, the holistic reward signal consists of multiple parts to represent the tasks, which makes the problem complicated. Existing multiagent RL algorithms search distributed policies with holistic reward signals directly, making it difficult to obtain an optimal policy for each task. This article provides efficient learning-based algorithms such that each agent can learn a joint optimal policy to accomplish these multiple tasks cooperatively with other agents. The main idea of the algorithms is to decompose the holistic reward signal for each agent into multiple parts according to the subtasks, and then the proposed algorithms learn multiple value functions with the decomposed reward signals and update the policy with the sum of distributed value functions. In addition, this article presents a theoretical analysis of the proposed approach. Finally, the simulation results for both discrete decision-making and continuous control problems have demonstrated the effectiveness of the proposed algorithms.

18.
Environ Pollut ; 269: 116100, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33246765

RESUMO

Subsurface wastewater infiltration systems (SWISs) have been widely used to treat rural domestic sewage. However, the low nitrogen removal and severe clogging problem always restrict the sustainability of SWISs for wastewater treatment. This study investigated the effects of aeration and biochar on the accumulation of nutrients and dissolved organic matter (DOM) in the substrate of loess soil-based SWISs for understanding the accumulation characteristics of DOM and the enhanced decontamination mechanism. The results showed that biochar addition could not improve the accumulation of nitrogen and phosphorus in the substrate, but could enhance denitrification (22%) via providing sufficient carbon for microorganisms. Moreover, the accumulation of organic matter in the substrate was also greatly affected. The DOM concentration of System D in the 40-60 cm layer reached 85.76 mg L-1, which indicated that biochar could release abundant DOM. Substrate DOM mainly contained humic acid-like and tryptophan-like substances. Moreover, the refractory macromolecular DOM components with high aromaticity and humification were found in the substrate below 60 cm of systems with biochar addition. This may be related to the DOM released by biochar and the extracellular polymeric substance (EPS) produced by microorganisms. It may affect the sustainability of the substrate to a certain extent, but fortunately that intermittent aeration could reduce this adverse effect. This research could provide new insights for preventing clogging and useful guidance for improving wastewater treatment performance in SWISs.


Assuntos
Solo , Águas Residuárias , Carvão Vegetal , Matriz Extracelular de Substâncias Poliméricas/química , Substâncias Húmicas/análise
19.
J Acquir Immune Defic Syndr ; 86(2): 200-207, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33196555

RESUMO

BACKGROUND: Medical mistrust, a result of systemic racism, is prevalent among Black Americans and may play a role in COVID-19 inequities. In a convenience sample of HIV-positive Black Americans, we examined associations of COVID-19-related medical mistrust with COVID-19 vaccine and COVID-19 treatment hesitancy and negative impacts of COVID-19 on antiretroviral therapy (ART) adherence. METHODS: Participants were 101 HIV-positive Black Americans (age: M = 50.3 years; SD = 11.5; 86% cisgender men; 77% sexual minority) enrolled in a randomized controlled trial of a community-based ART adherence intervention in Los Angeles County, CA. From May to July 2020, participants completed telephone interviews on negative COVID-19 impacts, general COVID-19 mistrust (eg, about the government withholding information), COVID-19 vaccine and treatment hesitancy, and trust in COVID-19 information sources. Adherence was monitored electronically with the Medication Event Monitoring System. RESULTS: Nearly all participants (97%) endorsed at least one general COVID-19 mistrust belief, and more than half endorsed at least one COVID-19 vaccine or treatment hesitancy belief. Social service and health care providers were the most trusted sources. Greater COVID-19 mistrust was related to greater vaccine and treatment hesitancy [b (SE) = 0.85 (0.14), P < 0.0001 and b (SE) = 0.88 (0.14), P < 0.0001, respectively]. Participants experiencing more negative COVID-19 impacts showed lower ART adherence, assessed among a subset of 49 participants [b (SE) = -5.19 (2.08), P = 0.02]. DISCUSSION: To prevent widening health inequities, health care providers should engage with communities to tailor strategies to overcome mistrust and deliver evidence-based information, to encourage COVID-19 vaccine and treatment uptake.


Assuntos
Afro-Americanos/psicologia , Vacinas contra COVID-19 , COVID-19/psicologia , Infecções por HIV/tratamento farmacológico , Adesão à Medicação/psicologia , Confiança/psicologia , Adulto , Antirretrovirais/uso terapêutico , COVID-19/tratamento farmacológico , COVID-19/etnologia , COVID-19/prevenção & controle , Feminino , Infecções por HIV/etnologia , Infecções por HIV/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Los Angeles , Masculino , Adesão à Medicação/estatística & dados numéricos , Pessoa de Meia-Idade , SARS-CoV-2 , Minorias Sexuais e de Gênero
20.
Water Res ; 189: 116665, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33254070

RESUMO

Effects of calcium ions and polyaluminum chloride (PACl) on membrane fouling in coagulation-ultrafiltration (UF) process were investigated in this study. Filtration tests demonstrated three interesting filtration behaviors: 1) high specific filtration resistance (SFR) of alginate solution with low CaCl2 or PACl addition (e. g. 3.51×1015 m·kg -1 under the condition of 1.5 mM CaCl2 addition); 2) unimodal pattern of alginate SFR with PACl or CaCl2 addition alone; 3) synergistic effects between CaCl2 and PACl on alginate SFR. It was found that, the foulant morphological changes driven by the thermodynamic mechanisms based on Flory-Huggins lattice theory take the critical roles in these filtration behaviors. Density functional theory (DFT) calculations showed that initial coordination of Ca2+ and Al3+ ions with alginates tended to form tetrahedron geometry and geometry of coordinating three terminal carboxyl groups, respectively, which facilitated to elongate the alginate chains (without clustering the flocs) and form more stable gel, increasing SFR. Improving Ca2+ and Al3+ dosages triggered transition to other geometries for clustering polymeric network and flocculation, reducing SFR. Due to the higher binding affinity of Ca2+ over Al3+, Ca2+ and Al3+ sequentially take roles of enlarging polymeric network and clustering the coordination compounds, and then facilitate to form large size flocs and reduce SFR, causing the synergistic effects between CaCl2 and PACl additions. The proposed thermodynamic mechanisms satisfactorily explained these interesting fouling behaviors, allowing to further optimize coagulation-UF process.


Assuntos
Ultrafiltração , Purificação da Água , Alginatos , Hidróxido de Alumínio , Cálcio , Floculação , Íons , Membranas Artificiais
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