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Species interactions such as facilitation and competition play a crucial role in driving species range shifts. However, density dependence as a key feature of these processes has received little attention in both empirical and modelling studies. Herein, we used a novel, individual-based treeline model informed by rich in situ observations to quantify the contribution of density-dependent species interactions to alpine treeline dynamics, an iconic biome boundary recognized as an indicator of global warming. We found that competition and facilitation dominate in dense versus sparse vegetation scenarios respectively. The optimal balance between these two effects was identified at an intermediate vegetation thickness where the treeline elevation was the highest. Furthermore, treeline shift rates decreased sharply with vegetation thickness and the associated transition from positive to negative species interactions. We thus postulate that vegetation density must be considered when modelling species range dynamics to avoid inadequate predictions of its responses to climate warming.
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Ecossistema , Árvores , Árvores/fisiologia , Aquecimento Global , Mudança Climática , ClimaRESUMO
Metal nanoclusters (NCs) hold great promise for expressing multipeak emission based on their well-defined total structure with diverse luminescent centers. Herein, we report the surface motif-dictated triple phosphorescence of Au NCs with dynamic color turning. The deprotonation-triggered isomerization of terminal thiouracils can evolve into a mutual transformation among their hierarchical motifs, thus serving a multipeak-emission expression with good tailoring. More importantly, the underlying electron transfer is thoroughly identified by excluding the radiative and nonradiative energy transfer, where electrons flow from the first phosphorescent state to the last two ones. The findings shed light on finely tailing motifs at the molecular level to motivate studies on customizable luminescence characteristics of metal NCs.
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The Hindu Kush high-altitude regions of Pakistan are currently experiencing severe consequences as a result of global warming. In this sense, increasing soil erosion and the quick melting of glaciers are two particularly evident effects. In such a scenario, understanding long-term temperature changes is crucial for making accurate forecasts about how the Hindu Kush region may experience regional temperature changes in the future. In this study, the climate tree-ring width (TRW) analysis designated a positive and significant correlation (r = 0.622, p < 0.001) between the TRW chronology and the June to September (summer) mean maximum temperature (MMT). Using the tree-ring width of Pinus wallichiana A. B. Jackson, we reconstructed summer temperatures in the Hindu Kush region from 1790 CE. Statistical analysis showed that the reconstruction model has explained 38.7% of the climate variance during the instrumental period of 1967 to 2018 CE. Five extremely warm summer periods (≥ 4 years; before the instrumental period 1967-2018 CE) of 1804-1830, 1839-1862, 1876-1879, 1905-1910, 1923-1935 CE, and six cold summer periods of 1790-1803, 1832-1838, 1863-1875, 1880-1904, 1911-1922, and 1936-1945 CE have been observed during the past 229 years. Individually, the year 1856 CE experienced severe warmth (31.85 °C), whereas 1794 CE was relatively cooler (29.60 °C). The spectral multi-taper method (MTM) shows significant (p < 0.05) cycles, which take place about every 9.3, 5.7, 4.2, and 3.6 years. In particular, the 9.3-year cycle, which closely aligns with the 11-year solar activity cycle, suggests a potential correlation between solar activity and local temperature fluctuations. Moreover, our reconstruction demonstrates a significant degree of consistency when compared to actual climate data and regional temperature reconstruction series, reporting a strong logic of trust in the reliability and accuracy of our findings. This evidence reaffirms that our reconstruction shows significant and dependable regional temperature signals, notably being representative for the Hindu Kush region.
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Estações do Ano , Temperatura , Árvores , Paquistão , História do Século XIX , História do Século XX , Pinus , História do Século XVIIIRESUMO
OBJECTIVES: To compare the clinical outcomes of anterolateral femoral interregional flap with turbocharge technique and traditional anterolateral femoral flap in repair of limblarge wound surface. METHODS: Clinical data of 38 patients withlimb large wound surface (11 cm×39 cm-16 cm× 65 cm) admitted to the Department of Prosthetics and Reconstruction of Sir Run Run Shaw Hospital from May 2018 to May 2022 were retrospectively analyzed. Eighteen patients were treated by anterolateral femoral perforator flap and superficial circumflex iliac artery flap (ALTP-SCIAP) with turbocharge technique (interregional flap group); while 20 patients were treated with unilateral or bilateral anterolateral femoral flaps, combined with skin grafting if necessary (traditional anterolateral femoral flap group). The survival of skin flap, repair of donor area, complications and patient satisfaction were compared between the two groups. RESULTS: In interregional flap group, 18 flaps were harvested and transplanted, the flap width, length and the viable area were (9.9±2.0) cm, (44.2±3.5) cm and (343.2±79.9) cm2, respectively. In traditional anterolateral femoral flap group and 29 flaps were harvested and transplanted, the flap width, length and the viable area were (11.0-2.8) cm (21.7-3.2) cm and (186.4-49.2) cm2, respectively. There were significant differences in the flap length and survival area between the two groups (t=22.365 and 8.345, P<0.05), but not significant difference in the flap width (t=1.525, P>0.05). In the interregional flap group, the donor site of flap was closed by direct suture in 11 cases, by skin retractor assisted suture in 6 cases, and by skin grafting in 1 case. In traditional anterolateral femoral flap group, the donor site of flap was closed by direct suture in 12 flaps, by skin retractor assisted suture in 11 flaps, and by skin grafting in 6 flaps. No significant difference was found between the two groups (χ2=2.657, P>0.05). The interregional flap group had lower postoperative complications rate (5.6% vs. 35.0%, χ2=4.942, P<0.05) and higher patient satisfaction rate (94.4% vs. 70.0%, χ2=4.448, P<0.05) than traditional anterolateral femoral flap group. CONCLUSIONS: Compared with the traditional anterolateral thigh flap, the anterolateral femoral interregional flap with turbocharge technique has a larger flap area, less complications, and higher patient satisfaction rate. With sacrificing only one donor area and sharing a set of vascular pedicles, it can repair "super long", "super large" or irregular limb wound defects maximally. At the same time, most of the donor areas of the flap can be sutured directly without skin grafting.
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Membrane breakage can lead to filtration failure, which allows harmful substances to enter the effluent, posing potential hazards to human health and the environment. This study is an innovative combination of fluorescence and ultraviolet-visible (UV-Vis) spectroscopy to identify membrane breakage. It aims to unravel more comprehensive information, improve detection sensitivity and selectivity, and enable real-time monitoring capabilities. Fluorescence and UV-Vis data are extracted through variance partitioning analysis (VPA) and integrated through a decision tree algorithm to form a superior system with enhanced discrimination capabilities. VPA improves discrimination efficiency by extracting key information from spectral data and eliminating redundancy. The decision tree algorithm, on the other hand, can process large amounts of data simultaneously. In addition, the method has a wide range of applications and can be used in various scenarios accurately. The scenarios include domestic sewage, micropollutant water, aquaculture wastewater, and secondary treated sewage. The experimental results validate the application of machine learning classifiers in membrane breakage detection with an accuracy rate of 96.8 % to 97.4 %.
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Aprendizado de Máquina , Membranas Artificiais , Filtração , Espectrometria de Fluorescência , Águas Residuárias , Esgotos , Algoritmos , Espectrofotometria Ultravioleta , Poluentes Químicos da Água/análiseRESUMO
The poor outcome of glioblastoma multiforme (GBM) treated with immunotherapy is attributed to the profound immunosuppressive tumor microenvironment (TME) and the lack of effective delivery across the blood-brain barrier. Radiation therapy (RT) induces an immunogenic antitumor response that is counteracted by evasive mechanisms, among which transforming growth factor-ß (TGF-ß) activation is the most prominent factor. We report an extracellular vesicle (EV)-based nanotherapeutic that traps TGF-ß by expressing the extracellular domain of the TGF-ß type II receptor and targets GBM by decorating the EV surface with RGD peptide. We show that short-burst radiation dramatically enhanced the targeting efficiency of RGD peptide-conjugated EVs to GBM, while the displayed TGF-ß trap reversed radiation-stimulated TGF-ß activation in the TME, offering a synergistic effect in the murine GBM model. The combined therapy significantly increased CD8+ cytotoxic T cells infiltration and M1/M2 macrophage ratio, resulting in the regression of tumor growth and prolongation of overall survival. These results provide an EV-based therapeutic strategy for immune remodeling of the GBM TME and eradication of therapy-resistant tumors, further supporting its clinical translation.
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Neoplasias Encefálicas , Vesículas Extracelulares , Glioblastoma , Fator de Crescimento Transformador beta , Microambiente Tumoral , Glioblastoma/terapia , Animais , Humanos , Neoplasias Encefálicas/terapia , Linhagem Celular Tumoral , Oligopeptídeos/química , Oligopeptídeos/administração & dosagem , Camundongos Endogâmicos C57BL , Receptor do Fator de Crescimento Transformador beta Tipo II/genética , Camundongos , FemininoRESUMO
Common vetch (Vicia sativa L.) is widely planted as forage, green manure and food. Phosphate (Pi) deficiency is an important constraint for legume crop production. In this study, P-deficiency tolerance in 40 common vetch collections was evaluated under hydroponic condition. The collections were clustered into three groups based on the tolerance level. Physiological responses to P-deficiency in two tolerant collections (418 and 426) in comparison with one sensitive collection (415) were investigated. Greater growth inhibition was observed in sensitive collection compared with two tolerant collections, although the inorganic phosphorus (P) content in sensitive collection was higher than those in tolerant collections. The internal and external purple acid phosphatase activity in plants showed no significant difference between 418 and 415 under low phosphate condition. Transcriptomic analysis in the tolerant collection 426 in response to Pi starvation showed that many common adaptive strategies were applied and PHOSPHATE STARVATION RESPONSE (PHR)-related Pi signaling and transporter genes were altered. VsPHT1.2 had the highest expression level in root among all VsPHT1s, and it was remarkably upregulated after short time of P-deficiency treatment in tolerant collections compared with sensitive collection. In conclusion, common vetch response to P starvation by altering the expressions of core genes involved in Pi transport and signaling, and the elevated expression of VsPHT1.2 gene might contribute to higher Pi acquisition efficiency in P-deficiency tolerant collections.
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Extreme drought events have increased, causing serious losses and damage to the social economy under current warming conditions. However, short-term meteorological data limit our understanding and projection of these extremes. With the accumulation of proxy data, especially tree-ring data, large-scale precipitation field reconstruction has provided opportunities to explore underlying mechanisms further. Using point-by-point regression, we reconstructed the April-September precipitation field in China for the past â¼530 years on the basis of 590 proxy records, including 470 tree-ring width chronologies and 120 drought/flood indices. Our regression models explained average 50% of the variance in precipitation. In the statistical test on calibration and verification, our models passed the significance level that assured reconstruction quality. The reconstruction data performed well, showing consistency and better quality than previously reported reconstructions. The first three leading modes of variability in the reconstruction revealed the main distribution modes of precipitation over China. Wet/drought and extremely wet/drought years accounted for 12.81%/10.92% (68 years/58 years) and 1.69%/3.20% (9 years/17 years) of the past â¼530 years in China, respectively. Major extreme drought events can be identified explicitly in our reconstruction. The detailed features of the Chongzhen Great Drought (1637-1643), the Wanli Great Drought (1585-1590), and the Ding-Wu Great Famine (1874-1879), indicated the existence of potentially different underlying mechanisms that need further exploration. Although further improvements can be made for remote uninhabited areas and large deserts, our gridded reconstruction of April-September precipitation in China over the past â¼530 years can provide a solid database for studies on the attribution of climate change and the mechanism of extreme drought events.
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PURPOSE: Appendiceal adenocarcinoma (AA) remains an orphan disease with limited treatment options for patients unable to undergo surgical resection. Evidence supporting the efficacy of combined VEGF and PD-1 inhibition in other tumor types provided a compelling rationale for investigating this combination in AA, where immune checkpoint inhibitors have not been explored previously. EXPERIMENTAL DESIGN: We conducted a prospective, single-arm phase II study evaluating efficacy and safety of atezolizumab in conjunction with bevacizumab (Atezo+Bev) in advanced, unresectable AA. RESULTS: Patients treated with the Atezo+Bev combination had 100% disease control rate (1 partial response, 15 stable disease) with progression-free survival (PFS) of 18.3 months and overall survival not-yet-reached with median duration of follow-up of 40 months. These survival intervals were significantly longer relative to a clinically and molecularly matched synthetic control cohort treated with cytotoxic chemotherapy designed for colorectal cancer (PFS of 4.4 months, P = 0.041). CONCLUSIONS: In light of recent data demonstrating a lack of efficacy of 5-fluorouracil-based chemotherapy, Atezo+Bev is a promising treatment option for patients with low-grade unresectable AA; further study is warranted. SIGNIFICANCE: AA remains an orphan disease with limited systemic therapy options for patients who are not candidates for surgical resection. These data suggest activity from combined VEGF and PD-L1 inhibition that warrants further study.