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1.
Accid Anal Prev ; 208: 107798, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39353301

RESUMO

Bottlenecks of the freeway generated especially by traffic accidents or temporary work zones contribute to significant reductions in system throughput and hinder the efficient traffic operations. It is imperative to take proactive measures to improve traffic state. With the rapid advancements in intelligent transportation, connected and autonomous vehicles (CAVs) have attracted much attention by its speculated capabilities in improving traffic safety and well-organized operational coordination. Therefore, reasonably utilizing the advantages of CAVs is possible to reduce the impact induced by bottlenecks. In this research, we propose a novel algorithm called CAV-Lead to obtain the CAV's regulated speed under mixed CAVs and human-driven vehicles (HVs) environment to improve the overall utilization of the freeway capacity near bottlenecks. Firstly, we illustrate the basic principle of the CAV-Lead algorithm that takes both microscopic and macroscopic traffic characteristics into account. Then, based on the local spatiotemporal traffic state, the CAV-Lead algorithm is proposed to determine each CAV's speed under mixed flow. Furthermore, a real-time simulation control framework considering the random behavior of HVs is presented. Moreover, several simulation evaluations including comparisons with basic scenarios and similar research are conducted under various CAV market penetration rates (MPRs). The results demonstrate that the CAV-Lead could improve the traffic performance, especially for the high traffic demand with certain MPRs.

2.
BMC Surg ; 24(1): 283, 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39363181

RESUMO

BACKGROUND: Current research on delayed gastric emptying (DGE) after pancreatic surgery is predominantly focused on pancreaticoduodenectomy (PD), with little exploration into DGE following total pancreatectomy (TP). This study aims to investigate the risk factors for DGE after TP and develop a predictive model. METHODS: This retrospective cohort study included 106 consecutive cases of TP performed between January 2013 and December 2023 at Peking Union Medical College Hospital (PUMCH). After applying the inclusion criteria, 96 cases were selected for analysis. These patients were randomly divided into a training set (n = 67) and a validation set (n = 29) in a 7:3 ratio. LASSO regression and multivariate logistic regression analyses were used to identify factors associated with clinically relevant DGE (grades B/C) and to construct a predictive nomogram. The ROC curve, calibration curve, decision curve analysis (DCA), and clinical impact curve (CIC) were employed to evaluate the model's prediction accuracy. RESULTS: The predictive model identified end-to-side gastrointestinal anastomosis, intraoperative blood transfusion, and venous reconstruction as risk factors for clinically relevant DGE after TP. The ROC was 0.853 (95%CI 0.681-0.900) in the training set and 0.789 (95%CI 0.727-0.857) in the validation set. The calibration curve, DCA, and CIC confirmed the accuracy and practicality of the nomogram. CONCLUSION: We developed a novel predictive model that accurately identifies potential risk factors associated with clinically relevant DGE in patients undergoing TP.


Assuntos
Esvaziamento Gástrico , Gastroparesia , Nomogramas , Pancreatectomia , Complicações Pós-Operatórias , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Pancreatectomia/efeitos adversos , Gastroparesia/etiologia , Gastroparesia/diagnóstico , Fatores de Risco , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologia , Esvaziamento Gástrico/fisiologia , Idoso , Adulto
3.
Phys Chem Chem Phys ; 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39356185

RESUMO

Singlet fission (SF) is considered as a promising strategy to overcome the Shockley-Queisser limit of single-junction solar cells. However, only a handful of chromophores were observed to undergo SF to date. To broaden the number of SF chromophores, we designed a series of phosphorus-doped perylenes based on the diradical character strategy and examined their SF feasibility using theoretical calculations. By analysis of frontier orbitals, diradical character and aromaticity, SF-capable candidates were prescreened. These analyses reveal that the diradical character of perylene is effectively enhanced by P-doping at bay- and peri-positions of perylene, making SF more thermodynamically feasible. However, the diradical character remains nearly unchanged when P atoms are doped at ortho-positions because the spin center cannot be stabilized, leading to a more endothermic SF. This study shows how SF-related energies and diradical character of SF chromophores are altered by P doping, and extends the SF-capable molecular library.

4.
J Transl Med ; 22(1): 900, 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39367493

RESUMO

BACKGROUND: Muscle invasive bladder cancer (MIBC) is a life-threatening malignant tumor characterized by high metastasis rates, poor prognosis, and limited treatment options. Immune checkpoint inhibitors (ICIs) targeting PD-1 and PD-L1 represent an emerging treatment for MIBC immunotherapy. However, the characteristics of patients likely to benefit from immunotherapy remain unclear. METHODS: We performed single-cell mass cytometry (CyTOF) analysis of 179,483 single cells to characterize potential immunotherapy-related cancer stem cells (CSCs)-like populations in the tumor microenvironment of 38 MIBC tissues. The upregulated expression of IGF2BP3 in CD274 + ALDH + CSC-like cells, which was associated with poor clinical prognosis, was analyzed by bulk RNA-sequencing data from an in-house cohort. The functional role of IGF2BP3 was determined through cell proliferation, colony formation, cell apoptosis and sphere formation assays. The regulation of SPHK1 expression by IGF2BP3 was  investigated using methylated RNA immunoprecipitation sequencing (MeRIP-seq) and bulk RNA-sequencing (bulk RNA-seq). We further utilized single-nucleus RNA sequencing (snRNA-seq) data from 67,988 cells of 25 MIBC tissues and single-cell RNA sequencing (scRNA-seq) data from MIBC patient-derived organoids to characterize the molecular features of bladder cancer cells co-expressing IGF2BP3 and SPHK1. Spatial transcriptomics (ST) and co-detection by indexing (CODEX) analysis were used to describe the spatial distribution and interactions of IGF2BP3 + SPHK1 + bladder cancer cells and immune cells. RESULTS: A subset of CD274 + ALDH + CSC-like cells was identified, associating with immunosuppression and low survival rates in MIBC patients. IGF2BP3, an m6A reader gene, was found to be upregulated in the CD274 + ALDH + CSC-like cell population and linked to poor clinical prognosis in MIBC. Knockout of IGF2BP3 dramatically promoted cell apoptosis and reduced cell proliferation in T24 cells. By integrating MeRIP-seq and bulk RNA-seq analyses, we identified SPHK1 served as a substrate for IGF2BP3 in an m6A-dependent manner. Further snRNA-seq, scRNA-seq, ST, and CODEX analysis revealed a closer topographical distance between IGF2BP3 + SPHK1 + bladder cancer cells and exhausted CD8 + T cells, providing one explanation for the superior response to immunotherapy in IGF2BP3 + SPHK1 + bladder cancer cells-enriched patients. Finally, an ICI-associated signature was developed based on the enriched genes of IGF2BP3 + SPHK1 + bladder cancer cells, and its potential ability to predict the response to immunotherapy was validated in two independent immunotherapy cohort. CONCLUSIONS: Our study highlighted the critical involvement of the IGF2BP3/SPHK1 signaling in maintaining the stemness of CSCs and promoting MIBC progression. Additionally, these findings suggested that the IGF2BP3/SPHK1 signaling might serve as a biomarker for prognosis and immunotherapy response in MIBC.


Assuntos
Imunoterapia , Invasividade Neoplásica , Células-Tronco Neoplásicas , Proteínas de Ligação a RNA , Transdução de Sinais , Neoplasias da Bexiga Urinária , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/imunologia , Humanos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Prognóstico , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Linhagem Celular Tumoral , Masculino , Feminino , Regulação Neoplásica da Expressão Gênica , Microambiente Tumoral , Pessoa de Meia-Idade , Proliferação de Células , Músculos/patologia , Músculos/metabolismo , Idoso , Multiômica
5.
Angew Chem Int Ed Engl ; : e202416291, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39389916

RESUMO

Dielectric capacitors harvest energy through an electrostatic process, which enables an ultrafast charging-discharging rate and ultrahigh power density. However, achieving high energy density (Wrec) and efficiency (η) simultaneously, especially when preserving them across a wide frequency/temperature range or cycling numbers, remains challenging. In this work, by especially introducing NaTaO3 into the representative ferroelectric relaxor of Bi0.5K0.5TiO3-Bi0.5Na0.5TiO3 and leveraging the mismatch between B-site atoms, we proposed a method of enhancing local structural fluctuation to refine the polar configuration and to effectively improve its overall energy-storage performances. As a consequence, the ceramic exhibits an ultrahigh Wrec of 15.0 J/cm3 and high η up to 80%, along with a very wide frequency stability of 10 - 200 Hz and extensive cycling number up to 108. In-depth local structure and chemical environment investigations, consisting of atom-scale electron microscopy, neutron total scattering, and solid-state nuclear magnetic resonance, reveal that the randomly distributed A/B-site atom pairs emerge in the system, leading to the evident local structural fluctuations and concomitant polymorphic polar nanodomains. These key ingredients contribute to the large polarization, minimal hysteresis, and high breakdown strength, thereby promoting energy-storage performances. This work opens a new path for designing high-performance dielectric capacitors via manipulating local structural fluctuations.

6.
Clin Cancer Res ; 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39226397

RESUMO

PURPOSE: Patients with HER2-positive breast cancer brain metastases have few effective systemic therapy options. In a prior study, pertuzumab with high-dose trastuzumab demonstrated a high clinical benefit rate (CBR) in the central nervous system (CNS) in patients with brain metastases. The current trial evaluated whether the addition of atezolizumab to this regimen would produce further improvements in CNS response. PATIENTS AND METHODS: This was a single-arm, multi-center, phase II trial of atezolizumab, pertuzumab, and high-dose trastuzumab for patients with HER2-positive breast cancer brain metastases. Participants received atezolizumab 1200 mg IV every 3 weeks (q3w), pertuzumab (loading dose 840 mg IV, then 420 mg IV q3w), and high-dose trastuzumab (6 mg/kg IV weekly for 24 weeks, then 6 mg/kg IV q3w). The primary endpoint was CNS overall response rate (ORR) per Response Assessment in Neuro-Oncology Brain Metastases (RANO-BM) criteria. Key secondary endpoints included CBR, overall survival (OS), and safety and tolerability of the combination. RESULTS: Among 19 enrolled participants, two had a confirmed intracranial partial response for a CNS-ORR of 10.5% (90% CI: 1.9%-29.6%). The study did not meet the prespecified efficacy threshold and was terminated early. The CBR was 42.1% at 18 weeks and 31.6% at 24 weeks. Seven patients (36.8%) required a dose delay or hold, and the most frequent any-grade adverse events were diarrhea (26.3%) and fatigue (26.3%). CONCLUSIONS: The addition of atezolizumab to pertuzumab plus high-dose trastuzumab does not result in improved CNS responses in patients with HER2-positive breast cancer brain metastases.

7.
PLoS Comput Biol ; 20(9): e1012415, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39226309

RESUMO

Revealing the relationship between neural network structure and function is one central theme of neuroscience. In the context of working memory (WM), anatomical data suggested that the topological structure of microcircuits within WM gradient network may differ, and the impact of such structural heterogeneity on WM activity remains unknown. Here, we proposed a spiking neural network model that can replicate the fundamental characteristics of WM: delay-period neural activity involves association cortex but not sensory cortex. First, experimentally observed receptor expression gradient along the WM gradient network is reproduced by our network model. Second, by analyzing the correlation between different local structures and duration of WM activity, we demonstrated that small-worldness, excitation-inhibition balance, and cycle structures play crucial roles in sustaining WM-related activity. To elucidate the relationship between the structure and functionality of neural networks, structural circuit gradients in brain should also be subject to further measurement. Finally, combining anatomical data, we simulated the duration of WM activity across different brain regions, its maintenance relies on the interaction between local and distributed networks. Overall, network structural gradient and interaction between local and distributed networks are of great significance for WM.


Assuntos
Memória de Curto Prazo , Modelos Neurológicos , Rede Nervosa , Memória de Curto Prazo/fisiologia , Rede Nervosa/fisiologia , Humanos , Biologia Computacional , Animais , Encéfalo/fisiologia , Simulação por Computador , Neurônios/fisiologia , Potenciais de Ação/fisiologia
8.
BMC Med Educ ; 24(1): 1040, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39334031

RESUMO

BACKGROUND: With the rapid advancement of technology, minimally invasive surgery, particularly laparoscopic surgery, has made significant progress in the field of surgery. Despite the advantages of laparoscopic surgery, a systematic training system for laparoscopic procedures is lacking in Chinese postgraduate medical education. Our study aims to explore the prevalence of laparoscopic training among resident and attending physicians in China and to assess the current state of training programs. METHODS: A 10-item questionnaire was distributed to 1,750 resident and attending physicians specializing in surgery across China, with 1,324 valid responses (75.7% response rate). The survey focused on demographics, training curriculum content, and feedback on training effectiveness. Data analysis was conducted using Microsoft Excel and IBM SPSS. RESULTS: Among the 1,324 respondents, 30.7% reported receiving laparoscopic training, primarily at the attending physician stage. Only 4% of resident physicians and 14% of attending physicians could independently perform complex laparoscopic surgeries. Most respondents (76.6%) could only assist in surgeries. The majority expressed a desire for more frequent and longer training sessions, with suture training being identified as the most beneficial. CONCLUSIONS: This study underscores the critical need for comprehensive laparoscopic training in China. Early, frequent, and structured training programs are essential for developing proficient laparoscopic surgeons. Future initiatives should focus on expanding access to training at all levels of medical education, ensuring continuous skill development and improved surgical care quality.


Assuntos
Currículo , Internato e Residência , Laparoscopia , Laparoscopia/educação , Humanos , China , Inquéritos e Questionários , Masculino , Feminino , Competência Clínica , Adulto , Cirurgiões/educação , Educação de Pós-Graduação em Medicina
9.
J Chem Phys ; 161(12)2024 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-39344888

RESUMO

The microstructure plays a crucial role in the manufacturing and application of polyacrylonitrile fibers, which serve as precursors for carbon fibers. Synchrotron radiation small angle x-ray scattering (SR-SAXS) is a non-destructive and precise technique for analyzing fiber structures. This study employed one-dimensional SR-SAXS mapping to extract key structural parameters such as periodicity, lamellae thickness, and the extent of amorphous regions, as well as the directional orientation in γ-irradiated, pre-oxidized polyacrylonitrile fibers. The analysis revealed a three-layered structure comprising a surface skin, a transitional layer, and a central core. Notably, the lamellar thickness exhibits a "U"-shaped distribution, while the long-period structures, amorphous regions, and orientational properties demonstrate a "wave-like" pattern. Within this structure, the skin exhibits a higher level of orientation, with the orientation decreasing progressively from the skin toward the core layer. The structure of the layered crystal was further corroborated by the morphological analysis. In addition, molecular simulations were performed to propose the mechanisms underlying the formation of this layered structure. This comprehensive investigation using SR-SAXS and one-dimensional mapping provides detailed insights into the microstructural and morphological characteristics of polyacrylonitrile fibers, which can inform future advancements in material processing and refinement techniques for the production of advanced fibers.

10.
Proc Natl Acad Sci U S A ; 121(37): e2403038121, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39226359

RESUMO

Proteostasis and genomic integrity are respectively regulated by the endoplasmic reticulum-associated protein degradation (ERAD) and DNA damage repair signaling pathways, with both pathways essential for carcinogenesis and drug resistance. How these signaling pathways coordinate with each other remains unexplored. We found that ER stress specifically induces the DNA-PKcs-regulated nonhomologous end joining (NHEJ) pathway to amend DNA damage and impede cell death. Intriguingly, sustained ER stress rapidly decreased the activity of DNA-PKcs and DNA damage accumulated, facilitating a switch from adaptation to cell death. This DNA-PKcs inactivation was caused by increased KU70/KU80 protein degradation. Unexpectedly, the ERAD ligase HRD1 was found to efficiently destabilize the classic nuclear protein HDAC1 in the cytoplasm, by catalyzing HDAC1's polyubiquitination at lysine 74, at a late stage of ER stress. By abolishing HDAC1-mediated KU70/KU80 deacetylation, HRD1 transmits ER signals to the nucleus. The resulting enhanced KU70/KU80 acetylation provides binding sites for the nuclear E3 ligase TRIM25, resulting in the promotion of polyubiquitination and the degradation of KU70/KU80 proteins. Both in vitro and in vivo cancer models showed that genetic or pharmacological inhibition of HADC1 or DNA-PKcs sensitizes colon cancer cells to ER stress inducers, including the Food and Drug Administration-approved drug celecoxib. The antitumor effects of the combined approach were also observed in patient-derived xenograft models. These findings identify a mechanistic link between ER stress (ERAD) in the cytoplasm and DNA damage (NHEJ) pathways in the nucleus, indicating that combined anticancer strategies may be developed that induce severe ER stress while simultaneously inhibiting KU70/KU80/DNA-PKcs-mediated NHEJ signaling.


Assuntos
Dano ao DNA , Proteína Quinase Ativada por DNA , Estresse do Retículo Endoplasmático , Ubiquitina-Proteína Ligases , Animais , Humanos , Camundongos , Linhagem Celular Tumoral , Reparo do DNA por Junção de Extremidades , Reparo do DNA , Proteína Quinase Ativada por DNA/metabolismo , Proteína Quinase Ativada por DNA/genética , Retículo Endoplasmático/metabolismo , Histona Desacetilase 1/metabolismo , Histona Desacetilase 1/genética , Autoantígeno Ku/metabolismo , Autoantígeno Ku/genética , Proteólise , Transdução de Sinais , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitinação
11.
J Am Chem Soc ; 146(40): 27460-27467, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39325860

RESUMO

Barocaloric materials hold great promise for next-generation solid-state cooling devices because of their green and efficient cooling performance. The insights into low-pressure-driven barocaloric materials are expected to pave the way for the widespread application of barocaloric refrigeration technology. Here, we reveal the low-pressure-driven large barocaloric effect (BCE) modulated by geometrical frustrations in Mn3Pt. The highest sensitivity to pressure of Mn3Pt in metal BCE materials results in an excellent temperature-change strength of 9.77 K 100-1 MPa-1. Neutron powder diffraction and first-principles calculations point out the dual effect of geometrical frustration on modulating the unusual BCE, which not only induces giant volume expansion by inspiring strong spin fluctuation and magnetic moment but also enhances the sensitivity of magnetic phase transition. The model of the dual effect of geometrical frustration in magnets with geometrical frustration is established, which will promote the research progress of barocaloric refrigeration devices.

12.
EBioMedicine ; 108: 105344, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39288533

RESUMO

BACKGROUND: Biliary atresia (BA) is a devastating neonatal cholangiopathy with an unclear pathogenesis, and prompt diagnosis of BA is currently challenging. METHODS: Proteomic and immunoassay analyses were performed with serum samples from 250 patients to find potential BA biomarkers. The expression features of polymeric immunoglobulin receptor (PIGR) were investigated using human biopsy samples, three different experimental mouse models, and cultured human biliary epithelial cells (BECs). Chemically modified small interfering RNA and adenovirus expression vector were applied for in vivo silencing and overexpressing PIGR in a rotavirus-induced BA mouse model. Luminex-based multiplex cytokine assays and RNA sequencing were used to explore the molecular mechanism of PIGR involvement in the BA pathogenesis. FINDINGS: Serum levels of PIGR, poliovirus receptor (PVR), and aldolase B (ALDOB) were increased in BA patients and accurately distinguished BA from infantile hepatitis syndrome (IHS). Combined PIGR and PVR analysis distinguished BA from IHS with an area under the receiver operating characteristic curve of 0.968 and an accuracy of 0.935. PIGR expression was upregulated in the biliary epithelium of BA patients; Th1 cytokines TNF-α and IFN-γ induced PIGR expression in BECs via activating NF-κB pathway. Silencing PIGR alleviated symptoms, reduced IL-33 expression, and restrained hepatic Th2 inflammation in BA mouse model; while overexpressing PIGR increased liver fibrosis and IL-33 expression, and boosted hepatic Th2 inflammation in BA mouse model. PIGR expression promotes the proliferation and epithelial-mesenchymal transition, and reduced the apoptosis of BECs. INTERPRETATION: PIGR participated in BA pathogenesis by promoting hepatic Th2 inflammation via increasing cholangiocytes derived IL-33; PIGR has the value as a diagnostic and therapeutic biomarker of BA. FUNDING: This study was financially supported by the National Natural Science Foundation of China (82170529), the National Key R&D Program (2021YFC2701003), and the National Natural Science Foundation of China (82272022).


Assuntos
Atresia Biliar , Biomarcadores , Modelos Animais de Doenças , Interleucina-33 , Fígado , Receptores de Imunoglobulina Polimérica , Células Th2 , Atresia Biliar/diagnóstico , Atresia Biliar/metabolismo , Atresia Biliar/etiologia , Atresia Biliar/imunologia , Animais , Humanos , Camundongos , Interleucina-33/metabolismo , Interleucina-33/genética , Receptores de Imunoglobulina Polimérica/metabolismo , Receptores de Imunoglobulina Polimérica/genética , Células Th2/imunologia , Células Th2/metabolismo , Fígado/metabolismo , Fígado/patologia , Fígado/imunologia , Masculino , Feminino , Lactente , Células Epiteliais/metabolismo , Citocinas/metabolismo
13.
Biochim Biophys Acta Rev Cancer ; 1879(6): 189183, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39303859

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is a digestive system malignancy characterized by challenging early detection, limited treatment alternatives, and generally poor prognosis. Although there have been significant advancements in immunotherapy for hematological malignancies and various solid tumors in recent decades, with impressive outcomes in recent preclinical and clinical trials, the effectiveness of these therapies in treating PDAC continues to be modest. The unique immunological microenvironment of PDAC, especially the abnormal distribution, complex composition, and variable activation states of tumor-infiltrating immune cells, greatly restricts the effectiveness of immunotherapy. Undoubtedly, integrating data from both preclinical models and human studies helps accelerate the identification of reliable molecules and pathways responsive to targeted biological therapies and immunotherapies, thereby continuously optimizing therapeutic combinations. In this review, we delve deeply into how PDAC cells regulate the immune microenvironment through complex signaling networks, affecting the quantity and functional status of immune cells to promote immune escape and tumor progression. Furthermore, we explore the multi-modal immunotherapeutic strategies currently under development, emphasizing the transformation of the immunosuppressive environment into an anti-tumor milieu by targeting specific molecular and cellular pathways, providing insights for the development of novel treatment strategies.

14.
Sci Total Environ ; 954: 176404, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39306133

RESUMO

There is increasing evidence that forage nutrition quality is becoming more unstable over time due to climate change and/or human activities. However, there are limited numbers of studies at the regional scale exploring the spatiotemporal patterns and driving mechanisms of temporal stability of nutrition quality. Therefore, this study quantified the spatiotemporal patterns of temporal stability of forage nutrition quality in alpine grasslands of the Qinghai-Tibet Plateau under the singular or combined influences of climate change and human activities in 2000-2020. Temporal stability of forage nutrition quality displayed obvious spatiotemporal patterns, with human activities altering the impact of climate change on these spatiotemporal patterns. Under combined effects of climate change and human activities, spatial average values of temporal stability of crude protein (CP), ash (Ash), ether extract (EE), water-soluble carbohydrates (WSC), acid detergent fiber (ADF), and neutral detergent fiber (NDF) decreased by 13.54 %, 7.40 %, 9.02 %, 17.78 %, 9.20 %, and 7.28 % across the whole grasslands, respectively. However, 39.43 %, 45.72 %, 42.98 %, 37.82 %, 42.27 %, and 43.50 % areas showed increasing trends for the temporal stability of CP, Ash, EE, WSC, ADF and NDF, respectively. Climate change predominated 46.15 %, 44.46 %, 44.22 %, 47.32 %, 28.68 %, and 45.31 % of the relative change of temporal stability of CP, Ash, EE, WSC, ADF, and NDF, but human activities had higher influence for 53.82 %, 55.53 %, 55.77 %, 52.55 %, 71.30 %, and 54.68 % of grasslands, respectively. Therefore, the spatial patterns of temporal stability of forage nutrition quality were shifting towards homogeneity, with an overall decrease in temporal stability but localized increases in alpine grasslands of the Qinghai-Tibet Plateau. The effects of climate change and human activities on forage nutrition quality were not always synergistic. The trade-off between nutrition quality and its temporal stability did not always exist, but varied with geographic position.

15.
Neuro Oncol ; 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39211994

RESUMO

BACKGROUND: There are limited data regarding HER2-low expression dynamics between matched primary tumors and brain metastases (BrMs) in breast cancer. HER2-low expression has emerged as a new therapeutic biomarker for highly active antibody-drug conjugates with emerging intracranial activity. METHODS: Patients with metastatic breast cancer (MBC) and BrMs seen at an NCI-designated center between 2003-2023 were identified. HER2 expression was defined as HER2-positive (3+,2+/ISH amplified), HER2-low (1+,2+/ISH negative), or HER2-0 by ASCO-CAP guidelines. Estrogen receptor (ER) status was defined as ER≥1%. Multivariate survival analyses by Cox proportional hazard models were determined from time of BrM resection to death or last follow-up between the 3 subtypes, controlling for ER and age. RESULTS: Among 197 matched primary and resected BrMs, 81% exhibited HER2 expression in the brain:61% HER2-positive, 20% HER2-low, and 19% HER2-0. Concordance was high in HER2-positive primary tumors with 100% retaining HER2 expression (97% retained HER2+ expression and 2.7% switched to HER2-low). HER2-0 primaries frequently showed HER2 gain in BrMs to HER2-low (35%) or HER2-positive (5.4%) status. Among 48 HER2-low primary tumors, 52% were discordant for HER2 status in the brain with 21% testing HER2-positive and 31% testing HER2-0. In adjusted analyses, patients with HER2-positive BrMs had significantly lower death risk than patients with HER2-low BrMs (HR=0.41, P=0.0006); no difference was observed between HER2-0 and HER2-low. CONCLUSIONS: In this retrospective analysis, HER2 expression is common in breast cancer BrMs, emphasizing the need for improved, non-invasive diagnostics. Patients with HER2-low and HER2-0 BrMs face inferior survival, presenting an unmet clinical need.

16.
Polymers (Basel) ; 16(16)2024 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-39204548

RESUMO

A functionalized ethylene-vinyl-alcohol (EVOH) nanofibrous membrane (NFM) was fabricated via co-electrospinning H4SiW12O40 (SiW12) and EVOH first, and then grafting citric acid (CCA) on the electrospun SiW12@EVOH NFM. Characterization with FT-IR, EDX, and XPS confirmed that CCA was introduced to the surface of SiW12@EVOH NFM and the Keggin structure of SiW12 was maintained well in the composite fibers. Due to a number of carboxyl groups introduced by CCA, the as-prepared SiW12@EVOH-CCA NFM can form a high number of hydrogen bonds with CR, and thus can be used to selectively absorb congo red (CR) in aqueous solutions. More importantly, the CR enriched in the NFM can be rapidly degraded via photocatalysis. SiW12 in the NFM acted as a photocatalyst, and the hydroxyl groups in the NFM acted as an electron donor to accelerate the photodegradation rate of CR. Meanwhile, the SiW12@EVOH-CCA NFM was regenerated and then exhibited a relatively stable adsorption capacity in five cycles of filtration-regeneration. The bifunctional nanofibrous membrane filter showed potential for use in the thorough purification of dye wastewater.

17.
Nat Commun ; 15(1): 7338, 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39187489

RESUMO

Relaxor ferroelectrics are highly desired for pulse-power dielectric capacitors, however it has become a bottleneck that substantial enhancements of energy density generally sacrifice energy efficiency under superhigh fields. Here, we demonstrate a novel concept of highly polarizable concentrated dipole glass in delicately-designed high-entropy (Bi1/3Ba1/3Na1/3)(Fe2/9Ti5/9Nb2/9)O3 ceramic achieved via substitution of multiple heterovalent ferroelectric-active principal cation species on equivalent lattice sites. The atomic-scaled polar heterogeneity of dipoles with different polar vectors between adjacent unit cells enables diffuse reorientation process but disables appreciable growth with electric fields. These unique features cause superior recoverable energy density of ~15.9 J cm-3 and efficiency of ~93.3% in bulk ceramics. We also extend the highly polarizable concentrated dipole glass to the prototype multilayer ceramic capacitor, which exhibits record-breaking recoverable energy density of ~26.3 J cm-3 and efficiency of ~92.4% with excellent temperature and cycle stability. This research presents a distinctive approach for designing high-performance energy-storage dielectric capacitors.

18.
ACS Appl Mater Interfaces ; 16(35): 46516-46526, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39163566

RESUMO

Real-time monitoring of UAV motor speed is crucial for enhancing control performance and ensuring flight safety. However, this task faces challenges such as difficult sensor installation and high costs. This study introduces a wireless rotational speed sensing system based on a UAV-rotary triboelectric nanogenerator (UR-TENG). By employing a carefully designed structure with soft contact and a freestanding-triboelectric-layer mode, UR-TENG exhibits characteristics like low friction, affordability, ease of production, and self-powering capability. This eliminates the need for an external power source and addresses the complexity of installation in the limited space of UAVs. Experimental findings demonstrate that UR-TENG possesses high sensitivity and stability, maintaining the structural integrity of the UAV. The goodness of fit is notably high at 0.99959, with a maximum error rate of only 0.014 within a range of 6270 rpm. Moreover, UR-TENG integrates with a microcontroller unit (MCU) and external circuitry to form a monitoring system. This system transmits electrical signals to a PC via a Wi-Fi module, facilitating real-time rotational speed sensing and anomaly detection. Finally, a practical application demonstration on a UAV validates the adaptability of UR-TENG to complex operational environments. This study presents a promising approach for online rotation monitoring of UAV motors, with potential for commercialization, and introduces new avenues for TENG application in UAV technology.

19.
J Am Chem Soc ; 146(35): 24296-24309, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39172075

RESUMO

Li-excess Mn-based disordered rock salt oxides (DRX) are promising Li-ion cathode materials owing to their cost-effectiveness and high theoretical capacities. It has recently been shown that Mn-rich DRX Li1+xMnyM1-x-yO2 (y ≥ 0.5, M are hypervalent ions such as Ti4+ and Nb5+) exhibit a gradual capacity increase during the first few charge-discharge cycles, which coincides with the emergence of spinel-like domains within the long-range DRX structure coined as "δ phase". Here, we systematically study the structural evolution upon heating of Mn-based DRX at different levels of delithiation to gain insight into the structural rearrangements occurring during battery cycling and the mechanism behind δ phase formation. We find in all cases that the original DRX structure relaxes to a δ phase, which in turn leads to capacity enhancement. Synchrotron X-ray and neutron diffraction were employed to examine the structure of the δ phase, revealing that selective migration of Li and Mn/Ti cations to different crystallographic sites within the DRX structure leads to the observed structural rearrangements. Additionally, we show that both Mn-rich (y ≥ 0.5) and Mn-poor (y < 0.5) DRX can thermally relax into a δ phase after delithiation, but the relaxation processes in these distinct compositions lead to different domain structures. Thermochemical studies and in situ heating XRD experiments further indicate that the structural relaxation has a larger thermodynamic driving force and a lower activation energy for Mn-rich DRX, as compared to Mn-poor systems, which underpins why this structural evolution is only observed for Mn-rich systems during battery cycling.

20.
J Environ Manage ; 368: 122090, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39126848

RESUMO

The saline wastewater produced in industrial activities and seawater use would flow into wastewater treatment plants and affect the characteristic of extracellular polymeric substance (EPS) of activated sludge, which could potentially impact the removal of antibiotics via adsorption. Nonetheless, the effect of salinity on trimethoprim adsorption by activated sludge extracellular polymeric substances at trace concentration and the underlying mechanism remain largely unknown. In this study, the effect of salinity on the adsorption removal of a typical antibiotic, i.e., trimethoprim (TMP) at trace concentration (25.0 µg/L) was evaluated. The results showed the content of EPS was decreased significantly from 56.36 to 21.70 mg/g VSS when the salinity was increased from 0 to 10 g/L. Protein fractions occupied the predominant component of EPS, whose concentration was decreased from 38.17 to 12.83 mg/g VSS. The equilibrium adsorption capacity of activated sludge for TMP was decreased by 49.70% (from 4.97 to 2.50 µg/g VSS). The fluorescence quenching results indicated the fluorescence intensity of tryptophan-like substances was decreased by 30% and the adsorption sites of EPS were decreased from 0.51 to 0.21 when the salinity was increased. The infrared spectrum and XPS results showed that the nitrogen-containing groups from protein were decreased significantly. The circular dichroic analysis showed α helix structure of protein in EPS was decreased with the increase of salinity, which was responsible for the decrease of adsorption capacity for TMP.


Assuntos
Matriz Extracelular de Substâncias Poliméricas , Salinidade , Esgotos , Trimetoprima , Esgotos/química , Adsorção , Trimetoprima/química , Matriz Extracelular de Substâncias Poliméricas/química , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Águas Residuárias/química , Poluentes Químicos da Água/química
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