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1.
Materials (Basel) ; 17(11)2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38893948

RESUMO

Halide perovskite materials have broad prospects for applications in various fields such as solar cells, LED devices, photodetectors, fluorescence labeling, bioimaging, and photocatalysis due to their bandgap characteristics. This study compiled experimental data from the published literature and utilized the excellent predictive capabilities, low overfitting risk, and strong robustness of ensemble learning models to analyze the bandgaps of halide perovskite compounds. The results demonstrate the effectiveness of ensemble learning decision tree models, especially the gradient boosting decision tree model, with a root mean square error of 0.090 eV, a mean absolute error of 0.053 eV, and a determination coefficient of 93.11%. Research on data related to ratios calculated through element molar quantity normalization indicates significant influences of ions at the X and B positions on the bandgap. Additionally, doping with iodine atoms can effectively reduce the intrinsic bandgap, while hybridization of the s and p orbitals of tin atoms can also decrease the bandgap. The accuracy of the model is validated by predicting the bandgap of the photovoltaic material MASn1-xPbxI3. In conclusion, this study emphasizes the positive impact of machine learning on material development, especially in predicting the bandgaps of halide perovskite compounds, where ensemble learning methods demonstrate significant advantages.

2.
Front Plant Sci ; 15: 1382934, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38835866

RESUMO

Objectives: Bamboo is a globally significant plant with ecological, environmental, and economic bene-fits. Choosing suitable native tree species for mixed planting in bamboo forests is an effective measure for achieving both ecological and economic benefits of bamboo forests. However, little is currently known about the impact of bamboo forests on nitrogen cycling and utilization efficiency after mixing with other tree species. Therefore, our study aims to compare the nitrogen cycling in pure bamboo forests with that in mixed forests. Methods: Through field experiments, we investigated pure Qiongzhuea tumidinoda forests and Q. tumidinoda-Phellodendron chinense mixed forests, and utilized 15N tracing technology to explore the fertilization effects and fate of urea-15N in different forest stands. Results: The results demonstrated the following: 1) in both forest stands, bamboo culms account for the highest biomass percentage (42.99%-51.86%), while the leaves exhibited the highest nitrogen concentration and total nitrogen uptake (39.25%-44.52%/29.51%-33.21%, respectively) Additionally, the average nitrogen uptake rate of one-year-old bamboo is higher (0.25 mg kg-1 a-1) compared to other age groups. 2) the urea-15N absorption in mixed forests (1066.51-1141.61 g ha-1, including 949.65-1000.07 g ha-1 for bamboo and 116.86-141.54 g ha-1 for trees) was significantly higher than that in pure forests (663.93-727.62 g ha-1, P<0.05). Additionally, the 15N recovery efficiency of culms, branches, leaves, stumps, and stump roots in mixed forests was significantly higher than that in pure forests, with increases of 43.14%, 69.09%, 36.84%, 51.63%, 69.18%, 34.60%, and 26.89%, respectively. 3) the recovery efficiency of urea-15N in mixed forests (45.81%, comprising 40.43% for bamboo and 5.38% for trees) and the residual urea-15N recovery rate in the 0-60 cm soil layer (23.46%) are significantly higher compared to those in pure forests (28.61%/18.89%). This could be attributed to the nitrogen losses in mixed forests (30.73%, including losses from ammonia volatilization, runoff, leaching, and nitrification-denitrification) being significantly lower than those in pure forests (52.50%). Conclusion: These findings suggest that compared to pure bamboo forests, bamboo in mixed forests exhibits higher nitrogen recovery efficiency, particularly with one-year-old bamboo playing a crucial role.

3.
Nano Lett ; 24(22): 6821-6827, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38787786

RESUMO

In the quasi-two-dimensional superconductor NbSe2, the superconducting transition temperature (Tc) is layer-dependent, decreasing by about 60% in the monolayer limit. However, for the extremely anisotropic copper-based high-Tc superconductor Bi2Sr2CaCu2O8+δ (Bi-2212), the Tc of the monolayer is almost identical with that of its bulk counterpart. To clarify the effect of dimensionality on superconductivity, here, we successfully fabricate ultrathin flakes of iron-based high-Tc superconductors CsCa2Fe4As4F2 and CaKFe4As4. It is found that the Tc of monolayer CsCa2Fe4As4F2 (after tuning to the optimal doping by ionic liquid gating) is about 20% lower than that of the bulk crystal, while the Tc of three-layer CaKFe4As4 decreases by 46%, showing a more pronounced dimensional effect than that of CsCa2Fe4As4F2. By carefully examining their anisotropy and the c-axis coherence length, we reveal the general trend and empirical law of the layer-dependent superconductivity in these quasi-two-dimensional superconductors.

4.
Transl Vis Sci Technol ; 13(5): 12, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38758570

RESUMO

Purpose: To evaluate the visual performance in adolescents undergoing orthokeratology (OrthoK) treatment with two different optical zone diameters (OZDs). Methods: This randomized, double-masked, self-controlled prospective study was conducted at Tianjin Eye Hospital (Tianjin, China) in June 2022. Thirty-six eligible schoolchildren were enrolled and fitted with corneal refractive therapy lenses with two sizes of OZDs (5 mm [5OZ] and 6 mm [6OZ]). Each participant was randomized to wear the 5OZ in one eye and the 6OZ in the contralateral eye. Subjective visual quality was assessed using visual acuity, refraction, contrast sensitivity function, and visual symptoms, and the objective optical quality was assessed using ocular higher order aberrations (HOAs) and modulation transfer function (MTF). Results: Thirty-five myopic children completed a 1-month follow-up visit. The 5OZ lens induced significantly smaller treatment zone diameters than the 6OZ lens (P < 0.001). Subjective visual quality did not differ significantly between the two groups. Compared to baseline, aberrations of Z40, coma-like, spherical-like, and total HOAs in both groups increased significantly (P < 0.05). For the 3-mm pupils, spherical aberration in the 5OZ group was significantly higher than that in the 6OZ group (P < 0.05). The MTF value of the 6OZ group was significantly higher than that of 5OZ group for 0.3 and 1.5 cycles per degree for the 3-mm pupils (P = 0.006 and P = 0.026, respectively). However, HOAs or MTF did not differ significantly between the two groups for the 5-mm pupils. Conclusions: The difference induced by varying OZD was significant only in the smaller pupil condition. The selection of OZD in OrthoK designs in real-world patient management should be done while considering individual pupil size. Translational Relevance: This study revealed that the objective visual quality of small OZD lenses was only slightly affected for the small pupil size.


Assuntos
Miopia , Procedimentos Ortoceratológicos , Refração Ocular , Acuidade Visual , Humanos , Feminino , Procedimentos Ortoceratológicos/métodos , Masculino , Acuidade Visual/fisiologia , Estudos Prospectivos , Adolescente , Miopia/terapia , Miopia/fisiopatologia , Criança , Método Duplo-Cego , Refração Ocular/fisiologia , Sensibilidades de Contraste , Lentes de Contato
5.
Curr Oncol ; 31(5): 2836-2845, 2024 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-38785496

RESUMO

The Laparoscopic Approach to Cervical Cancer (LACC) trial was published in 2018 and demonstrated that minimally invasive surgery (MIS) yields inferior survival outcomes in early-stage cervical cancer compared to open surgery. This study investigates how the results of the LACC trial have impacted the selection of the primary treatment modality and adjuvant radiation utilization in early-stage cervical cancer. Using the National Cancer Database (NCDB), we compared patients with stage IA2-IB1 cervical cancer before (1/2016-12/2017) and after (1/2019-12/2020) the LACC trial. A total of 7930 patients were included: 4609 before and 3321 after the LACC trial. There was a decline in MIS usage from 67% pre-LACC to 35% thereafter (p < 0.001). In both the pre- and post-LACC periods, patients undergoing radical MIS more frequently had small volume disease (pre-LACC tumors ≤ 2 cm, 48% MIS vs. 41% open, p = 0.023; post-LACC stage IA2, 22% vs. 15%, p = 0.002). Pre-LACC, MIS radical hysterectomy was associated with White race (82% vs. 77%, p = 0.001) and private insurance (63% vs. 54%, p = 0.004), while there was no difference in socioeconomic factors in the post-LACC period. Although the proportion of patients treated with primary chemoradiation remained stable, the post-LACC cohort had a younger median age (52.47 vs. 56.37, p = 0.005) and more microscopic disease cases (13% vs. 5.4%, p = 0.002). There was no difference in the rate of radiation after radical hysterectomy before and after the trial (26% vs. 24%, p = 0.3). Conclusions: Post-LACC, patients were less likely to undergo MIS but received adjuvant radiation at similar rates, and primary chemoradiation patients were younger and more likely to have microscopic disease.


Assuntos
Bases de Dados Factuais , Estadiamento de Neoplasias , Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias do Colo do Útero/terapia , Pessoa de Meia-Idade , Estados Unidos , Idoso , Histerectomia/métodos , Adulto , Radioterapia Adjuvante/estatística & dados numéricos
6.
Psychol Med ; 54(6): 1142-1151, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37818656

RESUMO

BACKGROUND: Remitted psychotic depression (MDDPsy) has heterogeneity of outcome. The study's aims were to identify subgroups of persons with remitted MDDPsy with distinct trajectories of depression severity during continuation treatment and to detect predictors of membership to the worsening trajectory. METHOD: One hundred and twenty-six persons aged 18-85 years participated in a 36-week randomized placebo-controlled trial (RCT) that examined the clinical effects of continuing olanzapine once an episode of MDDPsy had remitted with sertraline plus olanzapine. Latent class mixed modeling was used to identify subgroups of participants with distinct trajectories of depression severity during the RCT. Machine learning was used to predict membership to the trajectories based on participant pre-trajectory characteristics. RESULTS: Seventy-one (56.3%) participants belonged to a subgroup with a stable trajectory of depression scores and 55 (43.7%) belonged to a subgroup with a worsening trajectory. A random forest model with high prediction accuracy (AUC of 0.812) found that the strongest predictors of membership to the worsening subgroup were residual depression symptoms at onset of remission, followed by anxiety score at RCT baseline and age of onset of the first lifetime depressive episode. In a logistic regression model that examined depression score at onset of remission as the only predictor variable, the AUC (0.778) was close to that of the machine learning model. CONCLUSIONS: Residual depression at onset of remission has high accuracy in predicting membership to worsening outcome of remitted MDDPsy. Research is needed to determine how best to optimize the outcome of psychotic MDDPsy with residual symptoms.


Assuntos
Transtorno Depressivo Maior , Transtornos Psicóticos , Humanos , Olanzapina/uso terapêutico , Depressão , Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Maior/tratamento farmacológico , Transtornos Psicóticos/tratamento farmacológico , Sertralina/uso terapêutico
7.
Materials (Basel) ; 16(23)2023 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-38068228

RESUMO

Thorium monocarbide (ThC) is interesting as an alternative fertile material to be used in nuclear breeder systems and thorium molten salt reactors because of its high thermal conductivity, good irradiation performance, and wide homogeneous composition range. Here, the influence of carbon vacancy site and concentration on lattice distortions in non-stoichiometric ThC1-x (x = 0, 0.03125, 0.0625, 0.125, 0.1875, 0.25, or 0.3125) is systematically investigated using first-principle calculations by the projector augmented wave (PAW) method. The energy, mechanical parameters, and thermodynamic properties of the ThC1-x system are calculated. The results show that vacancy disordering has little influence on the total energy of the system at a constant carbon vacancy concentration using the random substitution method. As the concentration of carbon vacancies increases, significant lattice distortion occurs, leading to poor structural stability in ThC1-x systems. The changes in lattice constant and volume indicate that ThC0.75 and ThC0.96875 represent the boundaries between two-phase and single-phase regions, which is consistent with our experiments. Furthermore, the structural phase of ThC1-x (x = 0.25-0.3125) transforms from a cubic to a tetragonal structure due to its 'over-deficient' composition. In addition, the elastic moduli, Poisson's ratio, Zener anisotropic factor, and Debye temperature of ThC1-x approximately exhibit a linear downward trend as x increases. The thermal expansion coefficient of ThC1-x (x = 0-0.3125) exhibits an obvious 'size effect' and follows the same trend at high temperatures, except for x = 0.03125. Heat capacity and Helmholtz free energy were also calculated using the Debye model; the results showed the C vacancy defect has the greatest influence on non-stoichiometric ThC1-x. Our results can serve as a theoretical basis for studying the radiation damage behavior of ThC and other thorium-based nuclear fuels in reactors.

8.
BMC Health Serv Res ; 23(1): 621, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37312121

RESUMO

BACKGROUND: A significant number of late middle-aged adults with depression have a high illness burden resulting from chronic conditions which put them at high risk of hospitalization. Many late middle-aged adults are covered by commercial health insurance, but such insurance claims have not been used to identify the risk of hospitalization in individuals with depression. In the present study, we developed and validated a non-proprietary model to identify late middle-aged adults with depression at risk for hospitalization, using machine learning methods. METHODS: This retrospective cohort study involved 71,682 commercially insured older adults aged 55-64 years diagnosed with depression. National health insurance claims were used to capture demographics, health care utilization, and health status during the base year. Health status was captured using 70 chronic health conditions, and 46 mental health conditions. The outcomes were 1- and 2-year preventable hospitalization. For each of our two outcomes, we evaluated seven modelling approaches: four prediction models utilized logistic regression with different combinations of predictors to evaluate the relative contribution of each group of variables, and three prediction models utilized machine learning approaches - logistic regression with LASSO penalty, random forests (RF), and gradient boosting machine (GBM). RESULTS: Our predictive model for 1-year hospitalization achieved an AUC of 0.803, with a sensitivity of 72% and a specificity of 76% under the optimum threshold of 0.463, and our predictive model for 2-year hospitalization achieved an AUC of 0.793, with a sensitivity of 76% and a specificity of 71% under the optimum threshold of 0.452. For predicting both 1-year and 2-year risk of preventable hospitalization, our best performing models utilized the machine learning approach of logistic regression with LASSO penalty which outperformed more black-box machine learning models like RF and GBM. CONCLUSIONS: Our study demonstrates the feasibility of identifying depressed middle-aged adults at higher risk of future hospitalization due to burden of chronic illnesses using basic demographic information and diagnosis codes recorded in health insurance claims. Identifying this population may assist health care planners in developing effective screening strategies and management approaches and in efficient allocation of public healthcare resources as this population transitions to publicly funded healthcare programs, e.g., Medicare in the US.


Assuntos
Depressão , Medicare , Estados Unidos/epidemiologia , Pessoa de Meia-Idade , Humanos , Idoso , Depressão/diagnóstico , Depressão/epidemiologia , Estudos Retrospectivos , Hospitalização , Medição de Risco
9.
Sci Rep ; 13(1): 1746, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36720999

RESUMO

While it is known that social deprivation index (SDI) plays an important role on risk for acquiring Coronavirus Disease 2019 (COVID-19), the impact of SDI on in-hospital outcomes such as intubation and mortality are less well-characterized. We analyzed electronic health record data of adults hospitalized with confirmed COVID-19 between March 1, 2020 and February 8, 2021 from the INSIGHT Clinical Research Network (CRN). To compute the SDI (exposure variable), we linked clinical data using patient's residential zip-code with social data at zip-code tabulation area. SDI is a composite of seven socioeconomic characteristics determinants at the zip-code level. For this analysis, we categorized SDI into quintiles. The two outcomes of interest were in-hospital intubation and mortality. For each outcome, we examined logistic regression and random forests to determine incremental value of SDI in predicting outcomes. We studied 30,016 included COVID-19 patients. In a logistic regression model for intubation, a model including demographics, comorbidity, and vitals had an Area under the receiver operating characteristic curve (AUROC) = 0.73 (95% CI 0.70-0.75); the addition of SDI did not improve prediction [AUROC = 0.73 (95% CI 0.71-0.75)]. In a logistic regression model for in-hospital mortality, demographics, comorbidity, and vitals had an AUROC = 0.80 (95% CI 0.79-0.82); the addition of SDI in Model 2 did not improve prediction [AUROC = 0.81 (95% CI 0.79-0.82)]. Random forests revealed similar findings. SDI did not provide incremental improvement in predicting in-hospital intubation or mortality. SDI plays an important role on who acquires COVID-19 and its severity; but once hospitalized, SDI appears less important.


Assuntos
COVID-19 , Privação Social , Adulto , Humanos , Área Sob a Curva , Nível de Saúde , Hospitais , Disparidades nos Níveis de Saúde
10.
Clin Lymphoma Myeloma Leuk ; 22(1): e57-e64, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34446381

RESUMO

BACKGROUND: Doxorubicin carries a risk of congestive heart failure (CHF). Black race has been suggested as a risk factor for doxorubicin-related cardiotoxicity, but data are limited. We assessed whether HF occurs at higher rates in Black patients compared to White patients who receive doxorubicin for DLBCL, and evaluated race as an independent risk factor for the development of HF after adjusting for known risk factors. PATIENTS AND METHODS: We used SEER-Medicare to identify patients 66 years and older with DLBCL. We excluded patients with CHF documented prior to diagnosis with DLBCL. We assessed for hypertension, type 2 diabetes, coronary artery disease, and arrhythmias prior to diagnosis with DLBCL. The primary outcome was documented CHF at any point following DLBCL diagnosis. Secondary outcomes included CHF in the first year following diagnosis and death. We performed analyses additionally stratified by cumulative dose of doxorubicin. RESULTS: Our study population consisted of 8,604 patients (White 96.8%, Black 3.2%). In both Kaplan-Meier and competing risk analyses, we observed no significant difference in the incidence of CHF between Black and White patients, both before and after adjusting for covariates. Finally, we observed no significant differences in the incidence of CHF by race after stratification by cumulative doxorubicin dose. CONCLUSIONS: CHF is common following doxorubicin chemotherapy for DLBCL in older patients. No association was observed between Black race and the onset of heart failure in this setting. Rigorous screening for known clinical risk factors is likely more relevant than race in treatment selection and optimization.


Assuntos
Cardiotoxicidade/etiologia , Doxorrubicina/efeitos adversos , Insuficiência Cardíaca/induzido quimicamente , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Cardiotoxicidade/fisiopatologia , Feminino , Humanos , Incidência , Linfoma Difuso de Grandes Células B/patologia , Masculino , Grupos Raciais , Estudos Retrospectivos , Medição de Risco , Fatores de Risco
11.
Front Neurosci ; 15: 693217, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34720848

RESUMO

Purpose: To establish the time course of the subjective visual function changes during the first month of orthokeratology treatment in myopic children, and to investigate how the time course variations are associated with the objective optical quality changes and the axial length growth (ALG) after 1 year of treatment. Methods: A total of 58 myopic children aged from 8 to 16 years participated in this self-controlled prospective study. All subjects were fitted with designed spherical four-zone orthokeratology lenses. Subjective visual function was evaluated with orientation discrimination threshold (ODT), and objective optical quality was quantified with the high-order aberration root-mean-square (HOA-RMS) and the changing speed of HOA. The measurements were done before the lens fitting and 1 day, 1-, 2-, and 4-weeks after lens wear. Axial length was obtained at baseline and 1-year follow-up, and ALG was defined as the difference. One-way ANOVA was conducted to compare the difference for statistical analysis. Results: After lens fitting, the ODT time courses peaked on day 1 in 28 children, 1 week in 15 children, 2 weeks in 11 children, and 4 weeks in 4 children. In contrast, the HOA-RMS steadily rose during the first month, and the changing speed of HOA was only transiently elevated on day 1 after the initial lens wear. The ALG was 0.12 ± 0.20 mm in subjects whose ODT peaked at day 1, 0.08 ± 0.09 mm in subjects whose ODT peaked on 1-week, and 0.12 ± 0.15 mm in subjects whose ODT peaked on 2-week or later. There was no difference in axial growth among the subjects whose ODT peaked at different days (P = 0.734). Conclusion: While half ODT time course resembled the changing speed of HOA with a transient elevation on day 1, about a quarter of the ODT time course resemble the steadily rising of HOA-RMS, and the rest was located in the middle. The ALGs in children with different types of ODT time courses were similar.

12.
Phys Chem Chem Phys ; 23(35): 19834-19840, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34525134

RESUMO

The thermoelectric properties of monolayer triphosphide BiP3 are studied via first principles calculations and Boltzmann transport equation. First, the Seebeck coefficient, electrical conductivity and electron thermal conductivity at different temperatures are calculated using the Boltzmann transport equation with relaxation time approximation. It has been observed that BiP3 has a large power factor (265 × 10-4 W K-2 m-1, 700 K). Then, by analyzing the second-order interatomic force constant (IFCS), the atomic structure and phonon dispersion were studied, and the thermal conductivity of monolayer BiP3 was predicted in the temperature range of 300-800 K, and it was found that it had a very low thermal conductivity (2.13 W m-1 K-1) at room temperature. The thermal conductivity is mainly contributed by the branches of acoustics along in-plane transverse (TA). Finally, the maximum ZT value of monolayer BiP3 is 3.06 at 700 K, when the electron doping concentration is 2.35 × 1011 cm-2, which indicates that it is a promising thermoelectric material.

13.
PLoS One ; 16(7): e0255171, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34324574

RESUMO

OBJECTIVES: There is limited evidence on how clinical outcomes differ by socioeconomic conditions among patients with coronavirus disease 2019 (COVID-19). Most studies focused on COVID-19 patients from a single hospital. Results based on patients from multiple health systems have not been reported. The objective of this study is to examine variation in patient characteristics, outcomes, and healthcare utilization by neighborhood social conditions among COVID-19 patients. METHODS: We extracted electronic health record data for 23,300 community dwelling COVID-19 patients in New York City between March 1st and June 11th, 2020 from all care settings, including hospitalized patients, patients who presented to the emergency department without hospitalization, and patients with ambulatory visits only. Zip Code Tabulation Area-level social conditions were measured by the Social Deprivation Index (SDI). Using logistic regressions and Cox proportional-hazards models, we examined the association between SDI quintiles and hospitalization and death, controlling for race, ethnicity, and other patient characteristics. RESULTS: Among 23,300 community dwelling COVID-19 patients, 60.7% were from neighborhoods with disadvantaged social conditions (top SDI quintile), although these neighborhoods only account for 34% of overall population. Compared to socially advantaged patients (bottom SDI quintile), socially disadvantaged patients (top SDI quintile) were older (median age 55 vs. 53, P<0.001), more likely to be black (23.1% vs. 6.4%, P<0.001) or Hispanic (25.4% vs. 8.5%, P<0.001), and more likely to have chronic conditions (e.g., diabetes: 21.9% vs. 10.5%, P<0.001). Logistic and Cox regressions showed that patients with disadvantaged social conditions had higher risk for hospitalization (odds ratio: 1.68; 95% confidence interval [CI]: [1.46, 1.94]; P<0.001) and mortality (hazard ratio: 1.91; 95% CI: [1.35, 2.70]; P<0.001), adjusting for other patient characteristics. CONCLUSION: Substantial socioeconomic disparities in health outcomes exist among COVID-19 patients in NYC. Disadvantaged neighborhood social conditions were associated with higher risk for hospitalization, severity of disease, and death.


Assuntos
COVID-19/patologia , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Idoso , COVID-19/virologia , Etnicidade/estatística & dados numéricos , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Cidade de Nova Iorque , Características de Residência/estatística & dados numéricos , Fatores de Risco , Fatores Socioeconômicos
14.
Phys Chem Chem Phys ; 23(11): 6388-6396, 2021 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-33704316

RESUMO

Through first-principles calculations, we report the thermoelectric properties of two-dimensional (2D) hexagonal group-IV tellurides XTe (X = Ge, Sn and Pb), with quadruple layers (QL) in the Te-X-X-Te stacking sequence, as promising candidates for mid-temperature thermoelectric (TE) materials. The results show that 2D PbTe exhibits a high Seebeck coefficient (∼1996 µV K-1) and a high power factor (6.10 × 1011 W K-2 m-1 s-1) at 700 K. The lattice thermal conductivities of QL GeTe, SnTe and PbTe are calculated to be 2.29, 0.29 and 0.15 W m-1 K-1 at 700 K, respectively. Using our calculated transport parameters, large values of the thermoelectric figure of merit (ZT) of 0.67, 1.90, and 2.44 can be obtained at 700 K under n-type doping for 2D GeTe, SnTe, and PbTe, respectively. Among the three compounds, 2D PbTe exhibits low average values of sound velocity (0.42 km s-1), large Grüneisen parameters (∼2.03), and strong phonon scattering. Thus, 2D PbTe shows remarkable mid-temperature TE performance with a high ZT value under both p-type (2.39) and n-type (2.44) doping. The present results may motivate further experimental efforts to verify our predictions.

15.
Leuk Lymphoma ; 62(8): 1850-1859, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33627025

RESUMO

Positron emission tomography-computed tomography (PET-CT) has become the primary modality for staging in diffuse large B-cell lymphoma (DLBCL), whereas the role of staging bone marrow biopsy (BMB) has become less clear. In this analysis, we included 7,005 DLBCL patients in SEER-Medicare who received either PET-CT without BMB (PET-CT w/o BMB), CT with BMB (CT w/ BMB), or both PET-CT and BMB (PET-CT w/ BMB). The proportion of patients undergoing PET-CT increased across years of diagnosis, while the proportion undergoing CT or BMB decreased. In a fully adjusted Cox proportional hazards model, PET-CT w/ BMB was associated with a marginally superior OS compared to PET-CT w/o BMB. Notably, the association between PET-CT w/ BMB and OS was strongest in patients ≤70 years, but was not present when looking at individual stage of diagnosis. Overall, these data do not provide sufficient support to eliminate staging BMB in patients who undergo PET-CT.


Assuntos
Linfoma Difuso de Grandes Células B , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Idoso , Biópsia , Medula Óssea , Fluordesoxiglucose F18 , Humanos , Linfoma Difuso de Grandes Células B/diagnóstico , Medicare , Tomografia por Emissão de Pósitrons , Prognóstico , Estudos Retrospectivos , Estados Unidos/epidemiologia
16.
Am J Geriatr Psychiatry ; 29(7): 645-654, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33268022

RESUMO

OBJECTIVE: To examine the effect of older versus younger age on change in anthropometric and metabolic measures during extended treatment of psychotic depression with sertraline plus olanzapine. METHODS: Two hundred and sixty-nine men and women aged 18-85 years with an episode of psychotic depression were treated with open-label sertraline plus olanzapine for up to 12 weeks. Participants who remained in remission following an 8-week stabilization phase were eligible to participate in a 36-week randomized controlled trial (RCT) that compared the efficacy and tolerability of sertraline plus olanzapine with sertraline plus placebo. Weight, waist circumference and plasma lipids, glucose, HbA1c, and insulin were measured at regular intervals during the acute, stabilization and randomized phases of the study. Linear mixed models were used to analyze the trajectories of anthropometric and metabolic measures. RESULTS: Participants aged 60 years or older experienced less weight gain and less increase in cholesterol during the combined acute and stabilization phases of the study compared with those aged 18-59 years. At the acute-stabilization termination visit, mean weight in older participants was 6.5 lb. less than premorbid weight, whereas it was 17.9 lb. more than premorbid weight in younger participants. In the RCT, there was a significant interaction of treatment and age group for the trajectory of weight, but the post hoc tests that compared age groups within each treatment arm were not statistically significant. There were no clinically significant differences between younger and older participants in glycemic measures. CONCLUSION: Older patients with psychotic depression experienced less increase in weight and total cholesterol than their younger counterparts during acute and stabilization treatment with sertraline plus olanzapine. In the older group, weight gained during the acute and stabilization phases appeared to be partial restoration of weight lost during the index episode of depression, whereas weight gain in younger participants was not.


Assuntos
Antipsicóticos , Sertralina , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antipsicóticos/efeitos adversos , Benzodiazepinas/efeitos adversos , Depressão , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Olanzapina/efeitos adversos , Sertralina/efeitos adversos , Resultado do Tratamento , Adulto Jovem
17.
J Med Chem ; 63(24): 15541-15563, 2020 12 24.
Artigo em Inglês | MEDLINE | ID: mdl-33264017

RESUMO

Poly (ADP-ribose) polymerase (PARP) plays a significant role in DNA repair responses; therefore, this enzyme is targeted by PARP inhibitors in cancer therapy. Here we have developed a number of fused tetra- or pentacyclic dihydrodiazepinoindolone derivatives with excellent PARP enzymatic and cellular PARylation inhibition activities. These efforts led to the identification of pamiparib (BGB-290, 139), which displays excellent PARP-1 and PARP-2 inhibition with IC50 of 1.3 and 0.9 nM, respectively. In a cellular PARylation assay, this compound inhibits PARP activity with IC50 = 0.2 nM. Cocrystal of pamiparib shows similar binding sites with PARP with other PARP inhibitors, but pamiparib is not a P-gp substrate and shows excellent drug metabolism and pharmacokinetics (DMPK) properties with significant brain penetration (17-19%, mice). The compound is currently being investigated in phase III clinical trials as a maintenance therapy in platinum-sensitive ovarian cancer and gastric cancer.


Assuntos
Fluorenos/química , Inibidores de Poli(ADP-Ribose) Polimerases/química , Poli(ADP-Ribose) Polimerases/química , Animais , Sítios de Ligação , Carbazóis/química , Carbazóis/metabolismo , Carbazóis/farmacologia , Carbazóis/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Cães , Feminino , Fluorenos/metabolismo , Fluorenos/farmacologia , Fluorenos/uso terapêutico , Meia-Vida , Humanos , Indóis/química , Indóis/metabolismo , Indóis/farmacologia , Indóis/uso terapêutico , Isoenzimas/antagonistas & inibidores , Isoenzimas/metabolismo , Camundongos , Microssomos/metabolismo , Simulação de Acoplamento Molecular , Neoplasias/tratamento farmacológico , Inibidores de Poli(ADP-Ribose) Polimerases/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Ratos , Relação Estrutura-Atividade , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Materials (Basel) ; 13(21)2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-33143105

RESUMO

The hydrogen blistering phenomenon is one of the key issues for the target station of the accelerator-based neutron source. In the present study, the effect of monovacancies and divacancies defects on the solution, clustering and diffusion behaviors of H impurity in fcc-Pd were studied through first principles calculations. Our calculations prove that vacancies behave as an effective sink for H impurities. We found that, although the H-trap efficiency of the larger vacancy defect was reduced, its H-trap ability strengthened. There is a short-ranged area around the vacancy defects in which H impurities tend to diffuse to vacancy defects, gather and form hydrogen bubbles. Therefore, the characteristic of large vacancy defects formation in materials should be considered when screening anti-blistering materials for neutron-producing targets or when designing radiation resistant composite materials.

19.
Nanomaterials (Basel) ; 10(10)2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33081158

RESUMO

The thermoelectric property of the monolayer MAs2 (M = Ni, Pd and Pt) is predicted based on first principles calculations, while combining with the Boltzmann transport theory to confirm the influence of phonon and electricity transport property on the thermoelectric performance. More specifically, on the basis of stable geometry structure, the lower lattice thermal conductivity of the monolayer NiAs2, PdAs2 and PtAs2 is obtained corresponding to 5.9, 2.9 and 3.6 W/mK. Furthermore, the results indicate that the monolayer MAs2 have moderate direct bang-gap, in which the monolayer PdAs2 can reach 0.8 eV. The Seebeck coefficient, power factor and thermoelectric figure of merit (ZT) were calculated at 300, 500 and 700 K by performing the Boltzmann transport equation and the relaxation time approximation. Among them, we can affirm that the monolayer PdAs2 possesses the maximum ZT of about 2.1, which is derived from a very large power factor of 3.9 × 1011 W/K2ms and lower thermal conductivity of 1.4 W/mK at 700 K. The monolayer MAs2 can be a promising candidate for application at thermoelectric materials.

20.
Neoplasia ; 22(9): 431-440, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32652442

RESUMO

Pamiparib, an investigational Poly (ADP-ribose) polymerase (PARP) inhibitor in clinical development, demonstrates excellent selectivity for both PARP1 and PARP2, and superb anti-proliferation activities in tumor cell lines with BRCA1/2 mutations or HR pathway deficiency (HRD). Pamiparib has good bioavailability and is 16-fold more potent than olaparib in an efficacy study using BRCA1 mutated MDA-MB-436 breast cancer xenograft model. Pamiparib also shows strong anti-tumor synergy with temozolomide (TMZ), a DNA alkylating agent used to treat brain tumors. Compared to other PARP inhibitors, pamiparib demonstrated improved penetration across the blood brain barrier (BBB) in mice. Oral administration of pamiparib at a dose as low as 3 mg/kg is sufficient to abrogate PARylation in brain tumor tissues. In SCLC-derived, TMZ-resistant H209 intracranial xenograft model, combination of pamiparib with TMZ overcomes its resistance and shows significant tumor inhibitory effects and prolonged life span. Our data suggests that combination of pamiparib with TMZ has unique potential for treatment of brain tumors. Currently, the combination therapy of pamiparib with TMZ is evaluated in clinical trial [NCT03150862].


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Fluorenos/farmacologia , Poli(ADP-Ribose) Polimerase-1/antagonistas & inibidores , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Animais , Apoptose , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Proliferação de Células , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
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