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1.
Cell Mol Biol Lett ; 29(1): 50, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38594618

RESUMO

BACKGROUND: Melanoma is the most lethal skin cancer characterized by its high metastatic potential. In the past decade, targeted and immunotherapy have brought revolutionary survival benefits to patients with advanced and metastatic melanoma, but these treatment responses are also heterogeneous and/or do not achieve durable responses. Therefore, novel therapeutic strategies for improving outcomes remain an unmet clinical need. The aim of this study was to evaluate the therapeutic potential and underlying molecular mechanisms of RC48, a novel HER2-target antibody drug conjugate, either alone or in combination with dabrafenib, a V600-mutant BRAF inhibitor, for the treatment of advanced BRAF-mutant cutaneous melanoma. METHODS: We evaluated the therapeutic efficacy of RC48, alone or in combination with dabrafenib, in BRAF-mutant cutaneous melanoma cell lines and cell-derived xenograft (CDX) models. We also conducted signaling pathways analysis and global mRNA sequencing to explore mechanisms underlying the synergistic effect of the combination therapy. RESULTS: Our results revealed the expression of membrane-localized HER2 in melanoma cells. RC48 effectively targeted and inhibited the growth of HER2-positive human melanoma cell lines and corresponding CDX models. When used RC48 and dabrafenib synergically induced tumor regression together in human BRAF-mutant melanoma cell lines and CDX models. Mechanically, our results demonstrated that the combination therapy induced apoptosis and cell cycle arrest while suppressing cell motility in vitro. Furthermore, global RNA sequencing analysis demonstrated that the combination treatment led to the downregulation of several key signaling pathways, including the PI3K-AKT pathway, MAPK pathway, AMPK pathway, and FOXO pathway. CONCLUSION: These findings establish a preclinical foundation for the combined use of an anti-HER2 drug conjugate and a BRAF inhibitor in the treatment of BRAF-mutant cutaneous melanoma.


Assuntos
Antineoplásicos , Imidazóis , Imunoconjugados , Melanoma , Oximas , Neoplasias Cutâneas , Humanos , Melanoma/tratamento farmacológico , Melanoma/genética , Neoplasias Cutâneas/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Fosfatidilinositol 3-Quinases , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Imunoconjugados/genética , Imunoconjugados/uso terapêutico , Mutação
2.
Adv Sci (Weinh) ; : e2307691, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38454650

RESUMO

The 2D semiconductors are an ideal platform for exploration of bosonic fluids composed of coupled photons and collective excitations of atoms or excitons, primarily due to large excitonic binding energies and strong light-matter interaction. Based on first-principles calculations, it is demonstrated that the phonon polaritons formed by two infrared-active phonon modes in monolayer MoSi2 N4 and WSi2 N4 possess ultra-high confinement factors of around ≈105 and 103 , surpassing those of conventional polaritonic thin-film materials by two orders of magnitude. It is observed that the first bright exciton possesses a substantial binding energies of 750 and 740 meV in these two monolayers, with the radiative recombination lifetimes as long as 25 and 188 ns, and the Rabi splitting of the formed cavity-exciton polaritons reaching 373 and 321 meV, respectively. The effective masses of the cavity exciton polaritons are approximately 10-5 me , providing the potential for high-temperature quantum condensation. The ultra-confined and ultra-low-loss phonon polaritons, as well as strongly-coupled cavity exciton polaritons with ultra-small polaritonic effective masses in these two monolayers, offering the flexible control of light at the nanoscale, probably leading to practical applications in nanophotonics, meta-optics, and quantum materials.

3.
ACS Nano ; 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38320191

RESUMO

The electron-phonon interaction (EPI) and phonon-phonon interactions are ubiquitous in promising two-dimensional (2D) semiconductors, determining both electronic and thermal transport properties. In this work, based on ab initio calculations, the effects of intervalley scattering on EPI and higher-order four-phonon interactions of α-Te and ß-Te are investigated. Through the proposed selection rules for scattering channels and calculations of full electron-phonon scattering rates, we demonstrate that multiple nearly degenerate local valleys/peaks produce more scattering channels, resulting in stronger intervalley scattering over intravalley scattering. The lattice thermal conductivities of α-Te and ß-Te are decreased by as much as 10.9% and 30.8% by considering EPI under the carrier concentration of 2 × 1013 cm-2 (n-type) at 300 K compared to those limited by three-phonon scattering, respectively. However, when further considering four-phonon scattering, EPI reduces the lattice thermal conductivities by 2.6% and 19.4% for α-Te and ß-Te, respectively. Furthermore, it is revealed that the four-phonon interaction is more dominant in phonon transport for α-Te than that for ß-Te due to the presence of an acoustic-optical phonon gap in α-Te. Finally, we demonstrate strong intervalley scattering induces significant renormalization effects from EPI on all the constituent parameters of thermoelectric performance. Our results show the contributions of intervalley scattering to the electronic properties as well as thermal transport properties in band-convergent thermoelectric materials are essential and highlight the potential of monolayer tellurium as a promising candidate for advanced thermoelectric applications.

4.
Heliyon ; 10(4): e25677, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38370207

RESUMO

Reducing carbon emissions while maintaining simultaneous economic growth has been the focus of agricultural and environmental management research in recent times. To examine the influence of agricultural environmental regulations and related factors on agricultural carbon emissions efficiency, the entropy method was utilized to weigh each index and develop an index system for evaluating agricultural environmental regulations. This study utilizes the Super Slacked-Based Measure model that takes into account undesirable outputs. The research data used spans the years 2010-2019 and covers 31 provinces in China to calculate the efficiency of agricultural carbon emissions. A spatial Durbin model was employed to investigate the influence of environmental regulations and other influential factors on the efficiency of agricultural carbon emissions. The efficiency levels in the eastern region of China have consistently exceeded the national average, whereas the central region has demonstrated the lowest efficiency levels across the nation. Both the efficiency of agricultural carbon emissions and the intensity of agri-environmental regulations measured in this paper are strongly spatially autocorrelated between provinces. The environmental regulations index on local agricultural carbon emissions efficiency is significantly positive, while the effect on the agricultural carbon emissions efficiency in adjacent areas is not significant. Overall, agricultural environmental regulations effectively enhance agricultural carbon emissions efficiency, which in turn promotes technological innovation and economic growth. At the same time, local governments should actively adopt targeted strategies based on the actual situation of different regions in terms of their resource endowments and differences in the production characteristics of different crops.

5.
J Pediatr Urol ; 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-38000951

RESUMO

BACKGROUND: This meta-analysis aimed to evaluate the difference in postoperative complications as urethrocutaneous fistula or glans dehiscence, in children undergoing primary hypospadias repair with caudal block (CB) versus non-caudal block (NCB). METHODS: Data were obtained from MEDLINE, Embase, Web of Science, and the Cochrane Library. Comparative studies of CB versus NCB were identified, with reports of complications published or presented until October 2022. Subgroup analyses were performed based on study type, meatal location (distal only), type of NCB, surgeon and technique, and concentration and dose of anesthetics. RESULTS: Compared to the reference group of NCB, CB was not significantly associated with the development of complications following primary hypospadias repair (OR 1.40, 95 % CI 0.88-2.23). After adjusting for confounding factors, such as type of study(OR 1.51, 95%CI: 0.29-7.91), type of NCB[PB (OR 1.82, 95 % CI: 0.87-3.84), GA (OR 1.26, 95 % CI: 0.39-4.04)], meatal location (distal only) (OR 1.22, 95 % CI: 0.61-2.43), surgeon and technique (OR 1.37, 95 % CI: 0.59-3.14) and concentration and dose of anesthetics(OR 2.74, 95 % CI: 0.82-9.20), subgroup analyses revealed no significant association between CB and NCB (P > 0.05). DISCUSSION: Previous studies have found a correlation between CB and increased incidence of postoperative complications (urethrocutaneous fistula or glans dehiscence) of hypospadias, but different literature have suggested that surgical technique, surgical duration and the severity of hypospadias, rather than CB, are closely related to the occurrence of complications. In order to reduce confounding factors, subgroup analyses were conducted. The results showed that no correlation could be found in postoperative complications and CB. CONCLUSIONS: This meta-analysis compared the incidence of urethrocutaneous fistula or glans dehiscence in the CB and NCB groups for primary hypospadias repair in children, indicating that no clear correlation could be found in postoperative complications and CB. Subgroup analyses on study type, type of NCB, meatal location (distal only), surgeon and technique, and regional anesthetic concentration and dose supported this conclusion.

6.
Brain Sci ; 13(8)2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37626530

RESUMO

Early adverse life events (EALs) increase susceptibility to depression and impair cognitive performance, but the physiological mechanisms are still unclear. The target of this article is to clarify the impact of adverse childhood experiences on emotional and cognitive performance from the perspective of the heart-brain axis. We used the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) to test cognitive function and the Childhood Trauma Questionnaire (CTQ) to assess adverse childhood experiences. Heart rate variability (HRV) and electroencephalograms (EEG) were acquired at rest. We observed that subjects with depression had experienced more traumatic events during their childhood. Furthermore, they exhibited lower heart rate variability and higher power in the delta, theta, and alpha frequency bands. Moreover, heart rate variability partially mediated the association between childhood trauma exposure and depressive symptoms. Our findings suggested that adverse life events in childhood could influence the development of depression in adulthood, which might be linked to cardiac autonomic dysfunction and altered brain function.

7.
Front Plant Sci ; 14: 1201759, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37396636

RESUMO

Objective: Nutrient resorption efficiency and stoichiometric ratios are important strategies for understanding plants. The present study examined whether or not the nutrient resorption process of plant petals is similar to that of leaves and other vegetative organs, as well as the nutrient restriction status of the whole flowering process of plants in urban ecosystems. Methods: Four Rosaceae tree species, Prunus yedoensis Matsum, Prunus serrulata var. lannesiana, Malus micromalus Makino, and Prunus cerasifera 'Atropurpurea', were selected as urban greening species to analyze the contents of C, N, P, and K elements in the petals and their stoichiometric ratios and nutrient resorption efficiencies. Results: The results show interspecific differences in nutrient contents, stoichiometric ratios, and nutrient resorption efficiency of the fresh petals and petal litter of the four Rosaceae species. The nutrient resorption process was similar to that of the leaves before the petals fell. The nutrient contents of petals were higher than that of leaves at the global level, but the stoichiometric ratio and nutrient resorption efficiency of petals were lower. According to the "relative resorption hypothesis", N was limiting during the entire flowering period. The nutrient resorption efficiency of petals was positively correlated with nutrient variation. The correlation between the nutrient resorption efficiency of petals with nutrient content and stoichiometric ratio of petal litter was stronger. Conclusion: The experimental results provide scientific basis and theoretical support for the selection, scientific maintenance and fertilization management of Rosaceae tree species in urban greening.

8.
Front Med (Lausanne) ; 10: 1160828, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37425301

RESUMO

Introduction: Hand hygiene is a cost-effective measure to reduce healthcare-associated infections (HAIs) in healthcare facilities. The impact of the coronavirus disease 2019 (COVID-19) pandemic on hand hygiene performance (HHP) provided evidence for targeted hand hygiene intervention measures. Methods: This study evaluated the HHP rate in a tertiary hospital before and after the COVID-19 outbreak. HHP was checked by infection control doctors or nurses every day, and they inputted the HHP rate to the full-time infection control staff every week. A random examination of HHP was conducted by a confidential worker every month. The HHP of healthcare workers (HCWs) was monitored in the outpatient department, inpatient ward, and operating room from January 2017 to October 2022. The influence of COVID-19 prevention and control strategies on HHP was elucidated by analyzing the results of HHP during the study period. Results: The average HHP rate of HCWs was 86.11% from January 2017 to October 2022. The HHP rate of HCWs after the COVID-19 pandemic was statistically significantly higher than that before the pandemic (P < 0.001). The HHP rate was the highest (93.01%) in September 2022 when the local epidemic occurred. Among the different occupation categories, medical technicians showed the highest HHP rate (89.10%). The HHP rate was the highest after contact with body fluids or blood of patients (94.47%). Conclusion: The HHP rate of HCWs in our hospital showed an increasing trend in the recent 6 years, especially during the COVID-19 pandemic, and the increase was most obvious during the local epidemic.

9.
BMJ Paediatr Open ; 7(1)2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37463825

RESUMO

BACKGROUND: Hypospadias repair is a complex surgical procedure that involves correcting penile ventral curvature (VC) and performing urethroplasty. This study aims to evaluate the effectiveness of different strategies for VC correction and analyse the trends in hypospadias repair at a national centre in China. METHODS: Prospective data collection was conducted from 2019 to 2020 for patients undergoing hypospadias repair. The effectiveness of VC correction was assessed based on the degree of VC change with different strategies. Furthermore, the choice of surgical techniques for different types of hypospadias repair was analysed. RESULTS: A total of 434 patients were included, with a median preoperative VC degree of 50° (35°, 70°). All patients achieved a straight penis postoperatively, with 15.2% undergoing degloving, 28.6% undergoing degloving and dorsal plication (DP), 13.1% undergoing degloving and urethral plate transection (UPT), and 43.1% undergoing degloving, UPT and DP. Degloving alone was effective in correcting VC in 57.6% of patients with VC less than 30°. In our analysis, DP after UPT resulted in a higher degree of correction (25°) compared with DP after degloving alone (20°) (p<0.001). The study identified the current trends in hypospadias repair, with tubularised incised plate urethroplasty (TIP) being the most common technique used in distal hypospadias repair (70.6% of patients) and transverse preputial island flap urethroplasty (TPIFU) being preferred for proximal hypospadias repair (63.0%). CONCLUSIONS: Degloving alone is effective for correcting VC less than 30°. The majority of patients in our centre underwent UPT, and DP after UPT yielded better results compared with DP after degloving alone. Distal hypospadias repair commonly used TIP, while TPIFU was favoured for proximal hypospadias repair. TRIAL REGISTRATION NUMBER: ChiCTR1900023055.


Assuntos
Hipospadia , Masculino , Humanos , Hipospadia/cirurgia , Estudos Prospectivos , Pênis/cirurgia , Uretra/cirurgia , China/epidemiologia
10.
Opt Express ; 31(11): 17480-17493, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37381480

RESUMO

Coherent optical links are becoming increasingly attractive for intra-data center applications as data rates scale. Realizing the era of high-volume short-reach coherent links will require substantial improvements in transceiver cost and power efficiency, necessitating a reassessment of conventional architectures best-suited for longer-reach links and a review of assumptions for shorter-reach implementations. In this work, we analyze the impact of integrated semiconductor optical amplifiers (SOAs) on link performance and power consumption, and describe the optimal design spaces for low-cost and energy-efficient coherent links. Placing SOAs after the modulator provide the most energy-efficient link budget improvement, up to 6 pJ/bit for large link budgets, despite any penalties from nonlinear impairments. Increased robustness to SOA nonlinearities makes QPSK-based coherent links especially attractive, and larger supported link budgets enable the inclusion of optical switches, which could revolutionize data center networks and improve overall energy efficiency.

11.
Int J Psychophysiol ; 191: 1-8, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37348762

RESUMO

OBJECTIVES: To investigate the changes in sleep quality, heart rate variability (HRV) and resting-state electroencephalogram (rsEEG) in patients with major depressive disorder (MDD), and to explore whether HRV and rsEEG may be served as more convenient tools to assess sleep quality in MDD patients. METHOD: We included a total of 91 subjects (46 healthy controls and 45 MDD patients) and compared their sleep quality, HRV and power spectra of rsEEG. Correlation analyses were conducted to discuss the relationship between HRV and seven factors of PSQI. Multiple linear regression model was used to examine whether absolute band power could predict sleep quality in MDD patients. RESULTS: We found higher PSQI scores and lower levels of HRV in depressive individuals compared with healthy controls. In MDD patients, sleep latency was negatively correlated with RMSSD and HF. Delta, theta, and alpha band power of rsEEG were higher in MDD patients. Regression analyses showed delta band power of TP8, as well as theta, alpha band power of AF3 predicts PSQI score of MDD patients. CONCLUSIONS: The findings of our study show that some aspects of sleep problems had negative correlations with parasympathetic activity and the regression model supports that the band power of rsEEG may be used as a potential indicator to evaluate the sleep quality in MDD patients. SIGNIFICANCE: Cortical hyperarousal may be one of the reasons leading to poor sleep quality of MDD patients. And resting-state EEG can be used as a potential indicator for clinical assessment of MDD patients' sleep quality.


Assuntos
Transtorno Depressivo Maior , Distúrbios do Início e da Manutenção do Sono , Humanos , Transtorno Depressivo Maior/complicações , Qualidade do Sono , Eletroencefalografia , Análise de Regressão , Frequência Cardíaca/fisiologia
12.
ACS Appl Mater Interfaces ; 15(15): 19545-19559, 2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37037677

RESUMO

The convergence of multivalley bands is originally believed to be beneficial for thermoelectric performance by enhancing the charge conductivity while preserving the Seebeck coefficients, based on the assumption that electron interband or intervalley scattering effects are totally negligible. In this work, we demonstrate that ß-Bi with a buckled honeycomb structure experiences a topological transition from a normal insulator to a Z2 topological insulator induced by spin-orbit coupling, which subsequently increases the band degeneracy and is probably beneficial for enhancement of the thermoelectric power factor for holes. Therefore, strong intervalley scattering can be observed in both band-convergent ß- and aw-Bi monolayers. Compared to ß-Bi, aw-Bi with a puckered black-phosphorus-like structure possesses high carrier mobilities with 318 cm2/(V s) for electrons and 568 cm2/(V s) for holes at room temperature. We also unveil extraordinarily strong fourth phonon-phonon interactions in these bismuth monolayers, significantly reducing their lattice thermal conductivities at room temperature, which is generally anomalous in conventional semiconductors. Finally, a high thermoelectric figure of merit (zT) can be achieved in both bismuth monolayers, especially for aw-Bi with an n-type zT value of 2.2 at room temperature. Our results suggest that strong fourth phonon-phonon interactions are crucial to a high thermoelectric performance in these materials, and two-dimensional bismuth is probably a promising thermoelectric material due to its enhanced band convergence induced by the topological transition.

13.
J Texture Stud ; 54(3): 394-409, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36111886

RESUMO

Meat is the main source of protein nutrition for humans. However, given the increasing population and environmental pressure, a shortage of meat is expected in the future. The preparation of plant-based (meat) products using existing processing methods represents a breakthrough to solve the shortage of traditional animal meat in the future, and texture is a key issue determining whether plant-based (meat) products can replace traditional animal meat. Therefore, this review highlights recent progress in the texture of plant-based (meat) products. First, the texture changes in plant-based (meat) products were reviewed based on components (proteins, starch, lipids, food additives) and processing methods (processing factors, instrumental factors). Then, the current methods used to analyze the texture of plant-based (meat) products were summarized based on sensory evaluation and instrumental analysis (mechanical analysis, spectral analysis, and image analysis). Finally, this review outlined methods to improve the texture quality of plant-based (meat) products and analytical evaluation methods and provided an outlook on future research priorities.


Assuntos
Aditivos Alimentares , Carne , Humanos , Animais , Carne/análise
14.
Front Oncol ; 12: 1035487, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36313695

RESUMO

Diabetes mellitus often results in several complications, such as diabetic kidney disease (DKD) and end-stage renal diseases (ESRDs). Cancer patients often have the dysregulated glucose metabolism. Abnormal glucose metabolism can enhance the tumor malignant progression. Recently, lncRNAs have been reported to regulate the key proteins and signaling pathways in DKD development and progression and in cancer patients with diabetes. In this review article, we elaborate the evidence to support the function of lncRNAs in development of DKD and diabetes-associated cancer. Moreover, we envisage that lncRNAs could be diagnosis and prognosis biomarkers for DKD and cancer patients with diabetes. Furthermore, we delineated that targeting lncRNAs might be an alternative approach for treating DKD and cancer with dysregulated glucose metabolism.

15.
Front Psychiatry ; 13: 950910, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36159933

RESUMO

Backgrounds: The neural circuit mechanisms underlying depression remain unclear. Recently optogenetics has gradually gained recognition as a novel technique to regulate the activity of neurons with light stimulation. Scientists are now transferring their focus to the function of brain regions and neural circuits in the pathogenic progress of depression. Deciphering the circuitry mechanism of depressive-like behaviors may help us better understand the symptomatology of depression. However, few studies have summarized current progress on optogenetic researches into the neural circuit mechanisms of depressive-like behaviors. Aims: This review aimed to introduce fundamental characteristics and methodologies of optogenetics, as well as how this technique achieves specific neuronal control with spatial and temporal accuracy. We mainly summarized recent progress in neural circuit discoveries in depressive-like behaviors using optogenetics and exhibited the potential of optogenetics as a tool to investigate the mechanism and possible optimization underlying antidepressant treatment such as ketamine and deep brain stimulation. Methods: A systematic review of the literature published in English mainly from 2010 to the present in databases was performed. The selected literature is then categorized and summarized according to their neural circuits and depressive-like behaviors. Conclusions: Many important discoveries have been made utilizing optogenetics. These findings support optogenetics as a powerful and potential tool for studying depression. And our comprehension to the etiology of depression and other psychiatric disorders will also be more thorough with this rapidly developing technique in the near future.

16.
Membranes (Basel) ; 12(5)2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35629803

RESUMO

Food packaging plays a vital role in the food supply chain by acting as an additional layer to protect against food contamination, but the main function of traditional conventional packaging is only to isolate food from the outside environment, and cannot provide related information about food spoilage. Intelligent packaging can feel, inspect, and record external or internal changes in food products to provide further information about food quality. Importantly, intelligent packaging indicators will account for a significant proportion of the food industry's production, with promising application potential. In this review, we mainly summarize and review the upcoming progress in the classification, preparation, and application of food packaging indicators. Equally, the feasibility of 3D printing in the preparation of intelligent food packaging indicators is also discussed in detail, as well as the limitations and future directions of smart food packaging. Taken together, the information supported in this paper provides new insights into monitoring food spoilage and food quality.

17.
Artigo em Inglês | MEDLINE | ID: mdl-35409953

RESUMO

Due to the natural production properties, agriculture has been adversely affected by global warming. As an important link between individual household farmers and modern agriculture, it is crucial to study the influence of agricultural productive services on farmers' climate-responsive behaviors to promote sustainable development and improve agricultural production. In this paper, a questionnaire survey has been conducted among 374 maize farmers by using the combination of typical sampling and random sampling in Jilin Province of China. Moreover, the Poisson regression and the multi-variate Probit model have been used to analyze the effects of agricultural productive services on the choices of climate-responsive behaviors as well as the intensity of the behaviors. The results have shown that the switch to suitable varieties according to the frost-free period have been mostly common among maize growers in Jilin province. Agricultural productive services have a significant effect on the adoption intensity of climate- responsive behaviors, at the 1% level. Based on this conclusion, this paper proposes policy recommendations for establishing a sound agricultural social service system and strengthening the support for agricultural productive services. It has certain reference significance for avoiding climate risk and reducing agricultural pollution in regions with similar production characteristics worldwide.


Assuntos
Fazendeiros , Zea mays , Agricultura/métodos , China , Clima , Humanos
18.
Phys Chem Chem Phys ; 24(16): 9384-9393, 2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35383793

RESUMO

The emerging semiconductor boron arsenide (BAs) with high thermal conductivity has attracted much attention recently, due to its promising application to overcome the bottleneck of high-density heat generated in power electronics and optoelectronic devices. In this work, based on first-principles calculations, we find that cubic BAs possesses high intrinsic electron/hole mobilities and the ionized impurity scattering plays a more important role in carrier scattering, compared with other scattering processes. The mobilities can be significantly enhanced by 14.9% and 76.2% for electrons and holes, respectively, by strain engineering. The investigation of the optoelectronic properties of indirect semiconductor cubic BAs by considering the many-body excitonic effects reveals that the contribution from finite-momentum excitons to optical properties is larger for photon energy ranging from 2.25 eV to 3.50 eV, compared with that from zero-momentum excitons. Finally, we observe that the phonon-electron couplings to total lattice thermal conductivities are non-trivial at low temperatures. These findings provide new insight into the transport and optoelectronic properties of cubic BAs, which are beneficial for the acceleration of the application of this revolutionary thermal management material.

19.
Front Mol Biosci ; 9: 843150, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35223997

RESUMO

Retinal Degeneration (RD) is an inherited retinal disease characterized by degeneration of rods and cones photoreceptor cells and degeneration of retinal pigment epithelial cells. The age of onset and disease progression of RD are related to genes and environment. At present, research has discovered five genes closely related to RD. They are RHO, PDE6B, MERTK, RLBP1, RPGR, and researchers have developed corresponding gene therapy methods. Gene therapy uses vectors to transfer therapeutic genes, genetically modify target cells, and correct or replace disease-causing RD genes. Therefore, identifying the pathogenic genes of RD will play an important role in the development of treatment methods for the disease. However, the traditional methods of identifying RD-related genes are mostly based on animal experiments, and currently only a small number of RD-related genes have been identified. With the increase of biological data, Xgboost is purposed in this article to identify RP-related genes. Xgboost adds a regular term to control the complexity of the model, hence using Xgboost to find out true RD-related genes from complex and massive genes is suitable. The problem of overfitting can be avoided to some extent. To verify the power of Xgboost to identify RD-related genes, we did 10-cross validation and compared with three traditional methods: Random Forest, Back Propagation network, Support Vector Machine. The accuracy of Xgboost is 99.13% and AUC is much higher than other three methods. Therefore, this article can provide technical support for efficient identification of RD-related genes and help researchers have a deeper the understanding of the genetic characteristics of RD.

20.
Adv Sci (Weinh) ; 9(4): e2103648, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34904393

RESUMO

Exploring lead-free candidates and improving efficiency and stability remain the obstacle of hybrid organic-inorganic perovskite-based devices commercialization. Traditional trial-and-error methods seriously restrict the discovery especially for large search space, complex crystal structure and multi-objective properties. Here, the authors propose a multi-step and multi-stage screening scheme to accelerate the discovery of hybrid organic-inorganic perovskites A2 BB'X6 from a large number of candidates through combining machine learning with high-throughput calculations for pursuing excellent efficiency and thermal stability in solar cells. Followed by a series of screenings, the structure-property relationships mapping A2 BB'X6 properties are built and the predictions are close to reported experimental results. Successfully, four experimental-feasibly candidates with good stability, high Debye temperature and suitable band gap are screened out and further verified by density-functional theory calculations, in which the predicted efficiency for three lead-free candidates ((CH3 NH3 )2 AgGaBr6 , (CH3 NH3 )2 AgInBr6 and (C2 NH6 )2 AgInBr6 ) achieves 20.6%, 19.9% and 27.6% due to ultrabroadband absorption region ranging from UVC to IRC with excitonic radiative combination rates as low as 10 ps, large or intermediate polarons form with properties similar to CH3 NH3 PbI3 and the calculated thermal conductivities are 5.04, 4.39 and 5.16 Wm-1 K-1 , respectively, with Debye temperatures larger than 500 K, beneficial for suppression of both nonradiative combination and heat-induced degradation.

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