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1.
Nature ; 615(7950): 158-167, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36634707

RESUMO

Despite the success of PD-1 blockade in melanoma and other cancers, effective treatment strategies to overcome resistance to cancer immunotherapy are lacking1,2. Here we identify the innate immune kinase TANK-binding kinase 1 (TBK1)3 as a candidate immune-evasion gene in a pooled genetic screen4. Using a suite of genetic and pharmacological tools across multiple experimental model systems, we confirm a role for TBK1 as an immune-evasion gene. Targeting TBK1 enhances responses to PD-1 blockade by decreasing the cytotoxicity threshold to effector cytokines (TNF and IFNγ). TBK1 inhibition in combination with PD-1 blockade also demonstrated efficacy using patient-derived tumour models, with concordant findings in matched patient-derived organotypic tumour spheroids and matched patient-derived organoids. Tumour cells lacking TBK1 are primed to undergo RIPK- and caspase-dependent cell death in response to TNF and IFNγ in a JAK-STAT-dependent manner. Taken together, our results demonstrate that targeting TBK1 is an effective strategy to overcome resistance to cancer immunotherapy.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Evasão da Resposta Imune , Imunoterapia , Proteínas Serina-Treonina Quinases , Humanos , Evasão da Resposta Imune/genética , Evasão da Resposta Imune/imunologia , Imunoterapia/métodos , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , Organoides , Fatores de Necrose Tumoral/imunologia , Interferon gama/imunologia , Esferoides Celulares , Caspases , Janus Quinases , Fatores de Transcrição STAT
2.
PLoS Comput Biol ; 19(9): e1011442, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37695778

RESUMO

Biomolecular condensates are important structures in various cellular processes but are challenging to study using traditional experimental techniques. In silico simulations with residue-level coarse-grained models strike a balance between computational efficiency and chemical accuracy. They could offer valuable insights by connecting the emergent properties of these complex systems with molecular sequences. However, existing coarse-grained models often lack easy-to-follow tutorials and are implemented in software that is not optimal for condensate simulations. To address these issues, we introduce OpenABC, a software package that greatly simplifies the setup and execution of coarse-grained condensate simulations with multiple force fields using Python scripting. OpenABC seamlessly integrates with the OpenMM molecular dynamics engine, enabling efficient simulations with performance on a single GPU that rivals the speed achieved by hundreds of CPUs. We also provide tools that convert coarse-grained configurations to all-atom structures for atomistic simulations. We anticipate that OpenABC will significantly facilitate the adoption of in silico simulations by a broader community to investigate the structural and dynamical properties of condensates.


Assuntos
Condensados Biomoleculares , Simulação por Computador , Projetos de Pesquisa , Software
3.
Nucleic Acids Res ; 50(17): 9738-9747, 2022 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-36029149

RESUMO

The arrangement of nucleosomes inside chromatin is of extensive interest. While in vitro experiments have revealed the formation of 30 nm fibers, most in vivo studies have failed to confirm their presence in cell nuclei. To reconcile the diverging experimental findings, we characterized chromatin organization using a residue-level coarse-grained model. The computed force-extension curve matches well with measurements from single-molecule experiments. Notably, we found that a dodeca-nucleosome in the two-helix zigzag conformation breaks into structures with nucleosome clutches and a mix of trimers and tetramers under tension. Such unfolded configurations can also be stabilized through trans interactions with other chromatin chains. Our study suggests that unfolding from chromatin fibers could contribute to the irregularity of in vivo chromatin configurations. We further revealed that chromatin segments with fibril or clutch structures engaged in distinct binding modes and discussed the implications of these inter-chain interactions for a potential sol-gel phase transition.


Assuntos
Cromatina , Nucleossomos , Núcleo Celular , Conformação Molecular
4.
J Sci Food Agric ; 104(7): 4331-4341, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38299439

RESUMO

BACKGROUND: Human milk fat analog emulsion (HMFAE) is an emulsion that mimics the composition and structure of human milk (HM) fat globules. The application of HMFAE in infant formula requires a series of milk powder processing steps, such as pasteurization and spray drying. However, the effect of milk powder processing on fat digestion of HMFAE is still unclear. In this study, the influence of pasteurization and spray drying on the lipolysis behavior of HMFAE was studied and compared with HM using a simulated infant in vitro digestion model. RESULTS: Pasteurization and spray drying increased the flocculation and aggregation of lipid droplets in HMFAE during digestion. Spray drying destroyed the lipid droplet structure of HMFAE, and partial milk fat globule membrane-covered lipid droplets turned into protein-covered lipid droplets, which aggravated lipid-protein aggregation during gastric digestion and hindered fat digestion in the small intestine. The final lipolysis degree was in the order HM (64.55%) > HMFAE (63.41%) > pasteurized HMFAE (61.75%) > spray-dried HMFAE (60.57%). After complete gastrointestinal digestion, there were no significant differences in free fatty acid and sn-2 monoacylglycerol profile among the HMFAE, pasteurized HMFAE, and spray-dried HMFAE. CONCLUSION: Milk powder processing can reduce lipolysis by altering the lipid droplet structure of HMFAE and the degree of lipid droplet aggregation during digestion. © 2024 Society of Chemical Industry.


Assuntos
Leite Humano , Pasteurização , Lactente , Humanos , Leite Humano/química , Emulsões/análise , Secagem por Atomização , Pós/análise , Digestão
5.
BMC Plant Biol ; 23(1): 313, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37308832

RESUMO

BACKGROUND: Environmental factors difference is the key factor for the difference in the production, transformation and accumulation of effective components in plants. UPLC-MS/MS and multivariate statistical methods were applied to describe the region difference of amides compounds in Chinese prickly ash peels from different regions and their correlation with climatic factors and soil factors. RESULTS: Amides compounds contents were significantly higher in high altitude areas, with obvious altitude change trend. Two ecotypes were classified based on the amides compounds contents, one was the high altitude-cool type from Qinghai, Gansu, Sichuan and western Shaanxi province, and the other one was low altitude-warm type from eastern Shaanxi, Shanxi, Henan, Hebei and Shandong province. Amides compounds content were negatively correlated with annual mean temperature, max temperature of warmest month, mean temperature of wettest quarter and mean temperature of warmest quarter (P < 0.01). Except for hydroxy-γ-sanshool and ZP-amide A, the residual amides contents were significantly positively correlated with organic carbon, available nitrogen, phosphorus and potassium in soil and negatively correlated with soil bulk density. Low temperature, low precipitation and high organic carbon in soil were conducive to amides accumulation. CONCLUSIONS: This study aided in site specific exploration of high amides contents yielding samples, enriched the environment factors effects on amides compounds, and provided scientific foundation for the improvement of Chinese prickly ash peels quality and the location of high-quality production areas.


Assuntos
Aralia , Zanthoxylum , Amidas , Carbono , Cromatografia Líquida , Solo , Espectrometria de Massas em Tandem
6.
Environ Sci Technol ; 57(48): 19860-19870, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37976424

RESUMO

Electricity consumption and sludge yield (SY) are important indirect greenhouse gas (GHG) emission sources in wastewater treatment plants (WWTPs). Predicting these byproducts is crucial for tailoring technology-related policy decisions. However, it challenges balancing mass balance models and mechanistic models that respectively have limited intervariable nexus representation and excessive requirements on operational parameters. Herein, we propose integrating two machine learning models, namely, gradient boosting tree (GBT) and deep learning (DL), to precisely pointwise model electricity consumption intensity (ECI) and SY for WWTPs in China. Results indicate that GBT and DL are capable of mining massive data to compensate for the lack of available parameters, providing a comprehensive modeling focusing on operation conditions and designed parameters, respectively. The proposed model reveals that lower ECI and SY were associated with higher treated wastewater volumes, more lenient effluent standards, and newer equipment. Moreover, ECI and SY showed different patterns when influent biochemical oxygen demand is above or below 100 mg/L in the anaerobic-anoxic-oxic process. Therefore, managing ECI and SY requires quantifying the coupling relationships between biochemical reactions instead of isolating each variable. Furthermore, the proposed models demonstrate potential economic-related inequalities resulting from synergizing water pollution and GHG emissions management.


Assuntos
Gases de Efeito Estufa , Purificação da Água , Eliminação de Resíduos Líquidos , Águas Residuárias , Esgotos , Purificação da Água/métodos , Efeito Estufa
7.
J Gastroenterol Hepatol ; 38(12): 2185-2194, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37731216

RESUMO

BACKGROUND: In recent years, the incidence of alcoholic liver disease (ALD) has gradually increased, the development of ALD is attached great attentions. Nostoc commune Vauch. polysaccharide (NCVP) is beneficial to maintain the gut health, but the protective effect of NCVP on the liver has not been reported yet. PURPOSE: To study the protective effect and the underlying mechanisms of NCVP on ALD, a mouse model of acute ALD was established. STUDY DESIGN AND METHODS: We built an acute ALD mouse model and explored the protective effect of NCVP through the detection of cytokines, histological examination, determination of short chain fatty acids, and 16S rRNA analysis of gut microbiota. RESULTS: NCVP had hepatoprotective effects on acute alcohol-induced mice by improving antioxidant capacity, reducing oxidative stress and the serum cytokine levels (IL-1ß, IL-6, and TNF-α). Simultaneously, histopathological changes in liver indicated that NCVP could inhibit local hepatocyte necrosis, cytoplasmic vacuolation and inflammatory cell infiltration induced by alcohol. NCVP also increased the level of total short-chain fatty acids of acute ALD mice. In addition, NCVP could significantly decrease the Firmicutes/Bacteroidetes ratio and the abundance of Patescibacteria, Helicobacter, and Actinomycetes and increase the abundance of Lachospiraceae, Prevotellaceae-UCG-003, Lactobacillaceae, and Desulfovibrio. CONCLUSION: Our study proved that NCVP had in vivo hepatoprotective effect on acute ALD mice and provided scientific evidences that NCVP might be a promising drug candidate for the prevention and treatment of ALD.


Assuntos
Microbioma Gastrointestinal , Hepatopatias Alcoólicas , Nostoc commune , Animais , Camundongos , RNA Ribossômico 16S , Hepatopatias Alcoólicas/prevenção & controle , Polissacarídeos/farmacologia , Fígado/patologia , Etanol/efeitos adversos , Citocinas , Camundongos Endogâmicos C57BL
8.
J Sci Food Agric ; 103(9): 4668-4675, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36997692

RESUMO

BACKGROUND: This study investigated whether milk fat globule membrane as an emulsifier could make fat easier for infants to digest. An emulsion was formed using the membrane material, where anhydrous milk fat was used as the core material, milk fat globule membrane polar lipid (MPL) as the emulsifier, and soybean phospholipid (PL) and milk protein concentrate (MPC) incorporated as control emulsifiers. Structural characterization, glyceride composition, and fatty acid release from emulsions by in vitro digestion were investigated. RESULTS: The average particle size at the end of intestinal digestion was in the order MPL < PL < MPC, with diameters of 3.41 ± 0.51 µm, 3.53 ± 0.47 µm, and 10.46 ± 2.33 µm respectively. Meanwhile, laser scanning confocal microscopy results also illustrated that MPL could reduce the degree of aggregation during digestion. The lipolysis degree of MPL emulsion was higher than that of PL and MPC emulsions. MPL not only released higher levels of long-chain fatty acids, such as C18:1, C18:2, C18:3, which are of great significance for infant growth and development, but also released increased levels of C20:4 (arachidonic acid) and C22:6 (docosahexaenoic acid) than PL and MPC emulsions did. CONCLUSION: Fat droplets enveloped by milk fat globule MPLs were easier to digest and are therefore more suitable for infant formula. © 2023 Society of Chemical Industry.


Assuntos
Digestão , Lipólise , Lactente , Humanos , Emulsões/química , Ácidos Graxos , Intestinos , Emulsificantes
9.
BMC Plant Biol ; 22(1): 251, 2022 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-35596133

RESUMO

BACKGROUND: Flavonoids have strong free radical scavenging and antioxidant capacity. The high abundance of flavonoids in Chinese prickly ash peels have many benefits to human health. In this study, 'Hancheng Dahongpao', a main cultivar, was taken as materials to investigate the flavonoids biosynthesis mechanism of Zanthoxylum bungeanum Maxim at three key development stages by integration of metabolomics and transcriptomics analysis. RESULTS: A total of 19 differentially accumulated metabolites were identified, the key flavonoids compounds were kaempferol, quercetin and their glycoside derivatives, and two major anthocyanins (peonidin O-hexoside and peonidin 3-O-glucoside). 5 gene networks/modules including 15 important candidate genes were identified, which was highly correlated with flavonoids. Among these genes, ZM-163828 and ZM-184209 were strongly correlated with kaempferol and quercetin, and ZM-125833 and ZM-97481 were controlled the anthocyanins biosynthesis. Moreover, it was shown that MYB-ZM1, MYB-ZM3, MYB-ZM5, MYB-ZM6 and MYB-ZM7 coordinately controlled flavonoids accumulation through regulating the structural genes. CONCLUSIONS: Generally, this study systematically revealed the flavonoids metabolic pathways and candidate genes involved in flavonoids biosynthesis and laid a foundation for the potential targets for the breeding of new valuable Chinese prickly ash cultivars.


Assuntos
Antocianinas , Zanthoxylum , Antocianinas/metabolismo , Flavonoides/metabolismo , Quempferóis/metabolismo , Metabolômica , Melhoramento Vegetal , Quercetina/metabolismo , Transcriptoma , Zanthoxylum/genética
10.
BMC Gastroenterol ; 22(1): 245, 2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-35570284

RESUMO

BACKGROUND: Calcification of abdominal lymph node is a common clinical phenomenon, but it is extremely rare to cause serious adverse clinical outcomes. In the present case, the ruptured hemorrhage of the oesophagogastric fundic varices occurred as a result of portal hypertension due to compression of the portal vein by calcified lymph nodes. The patient was treated with medication, interventional therapy, endoscopic therapy, and surgery, respectively and the four different treatment options for the bleeding are worth summarizing. The etiology of this case is extremely rare and is the first to be reported in the world. CASE PRESENTATION: A 32-year-old male patient with no apparent causes of sudden onset of vomiting of blood, the patient underwent four different treatment methods to stop the hemorrhage. The combined diagnosis of whole abdomen enhanced CT and angiography was calcified abdominal lymph nodes compressing the portal vein, leading to portal hypertension and resulting in esophageal and gastric variceal bleeding. Postoperatively, a biopsy of the caseous tubercular tissue of the abdominal wall observed intraoperatively was performed and the biopsy did not show a tubercular component. Therefore, the extensive intra-abdominal lymph node calcification was not associated with tuberculosis. The patient's bleeding ceased after surgery. CONCLUSION: This case has improved the clinician's understanding of the etiology of non-cirrhotic portal hypertension. Based on this, and with this case, the differences between various hemostatic measures were studied in depth.


Assuntos
Varizes Esofágicas e Gástricas , Hipertensão Portal , Tuberculose , Abdome/diagnóstico por imagem , Adulto , Varizes Esofágicas e Gástricas/complicações , Varizes Esofágicas e Gástricas/terapia , Hemorragia Gastrointestinal/complicações , Hemorragia Gastrointestinal/terapia , Humanos , Hipertensão Portal/complicações , Linfonodos , Masculino , Veia Porta , Tuberculose/complicações
11.
Environ Res ; 215(Pt 1): 114127, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36041541

RESUMO

Understanding the relationship between precipitation and SARS-CoV-2 is significant for combating COVID-19 in the wet season. However, the causes for the variation of SARS-CoV-2 transmission intensity after precipitation is unclear. Starting from "the Zhengzhou event," we found that the virus-laden standing water formed after precipitation might trigger some additional routes for SARS-CoV-2 transmission and thus change the transmission intensity of SARS-CoV-2. Then, we developed an interdisciplinary framework to examine whether the health risk related to the virus-laden standing water needs to be a concern. The framework enables the comparison of the instant and lag effects of precipitation on the transmission intensity of SARS-CoV-2 between city clusters with different formation risks of the virus-laden standing water. Based on the city-level data of China between January 01, 2020, and December 31, 2021, we conducted an empirical study. The result showed that in the cities with a high formation risk of the virus-laden standing water, heavy rain increased the instant transmission intensity of SARS-CoV-2 by 6.2% (95%CI: 4.85-10.2%), while in the other cities, precipitation was uninfluential to SARS-CoV-2 transmission, revealing that the health risk of the virus-laden standing water should not be underestimated during the COVID-19 pandemic. To reduce the relevant risk, virus-laden water control and proper disinfection are feasible response strategies.


Assuntos
COVID-19 , SARS-CoV-2 , COVID-19/epidemiologia , Óxido de Deutério , Humanos , Pandemias , Água
12.
Chem Biodivers ; 19(3): e202100965, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35112481

RESUMO

Wild Chinese prickly ash resources provide a valuable genetic resource for Zanthoxylum bungeanum Maxim improvement and breeding. The Qinling Mountains was an abundant source for wild Chinese prickly ash. In this study, the phenolic and flavonoid compounds of wild germplasm resources from different altitudes and six cultivated varieties were analyzed by high performance liquid chromatography (HPLC). The chromatograms of them were essentially consistent, although their chemical composition contents were greatly different. The thirty samples were divided into three categories through the hierarchical clustering analysis. Catechin, hyperoside and quercitrin were considered to be key compounds for the quality evaluation, and by contrast, the wild samples with an altitude of 2300±50 m (Group IV) had the highest content of key compounds, and presented stronger antioxidant activity and antibacterial ability, indicating that these wild samples could be identified as the excellent breeding resources. This is the first time to evaluate the quality of wild Chinese prickly ash at different altitudes in Qinling Mountains. These excellent wild germplasm resources provided substantial potential accessions for use directly in Chinese prickly ash breeding programs.


Assuntos
Zanthoxylum , China , Cromatografia Líquida de Alta Pressão , Flavonoides , Fenóis/química , Zanthoxylum/química
13.
Int J Phytoremediation ; 24(11): 1205-1212, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34995152

RESUMO

Soil lead (Pb) contamination has caused severe environmental threats and is in urgent need of remediation. This study was aimed to explore the feasibility of using the Miscanthus-microbe combination to reduce Pb pollution in the farmland surrounding a lead-zinc mining area. We have screened three heteroauxin (IAA)-producing microbes (Lelliottia jeotgali MR2, Klebsiella michiganensis TS8, and Klebsiella michiganensis ZR1) with high Pb tolerance. The IAA-producing ability of the mixed-species was stronger than that of the single bacterium. In pot experiments, the mixed-species of MR2-ZR1 and MR2-TS8 had better performance in enhancing the weight of Miscanthus grass (increased by 22.2-53.6% compared to the control group without inoculating microbes). The remediation efficiency of Pb was significantly higher in the MR2 (30.79%), MR2-TS8 (24.96%), and TS8-ZR1 (21.10%) groups than that in the control group (6.75%). We speculated that MR2 and mixed species of MR2-TS8 and TS8-ZR1 could promote the percentages of activated Pb fractions in soils and increase the Pb uptake of M. floridulus (Lab.). These results implied that the MR2-TS8 mixed-species might be selected as the effective microbial agent to simultaneously enhance the remediation efficiency of Pb-contaminated soils and the biomass of M. floridulus (Lab.).


This study investigated the effects of single and mixed IAA-producing bacteria on the phytoremediation of Pb-contaminated soils and the growth of energy crop-Miscanthus floridulus (Lab.). The results showed that the bacterial combination of MR2-TS8 may be most suitable as a microbial agent to simultaneously enhance the remediation efficiency of Pb in soils and the biomass of M. floridulus (Lab.) compared to the single strain. This study significantly contributes to offering a potential and effective strategy for Pb remediation of farmland around mine areas.


Assuntos
Poluentes do Solo , Biodegradação Ambiental , Ácidos Indolacéticos , Klebsiella , Chumbo , Poaceae , Solo , Poluentes do Solo/análise
14.
Molecules ; 27(12)2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35744991

RESUMO

The chemotypic and the content variation in taste substances and nutrients in 'Shushanggan apricot' fruits were detected by UPLC-MS/MS. A total of 592 compounds were identified, of which sucrose contributed mainly to the sweet taste and malic acid and citric acid were important organic acids affecting sweet-sour taste. γ-linolenic acid, α-linolenic acid and linoleic acid were the dominant free fatty acids, and neochlorogenic acid and chlorogenic acid were the predominant phenolic acids. Fruit taste was positively correlated with sucrose and negatively correlated with malic acid and citric acid. The differential metabolites were significantly enriched in the biosynthesis of amino acids and 2-oxocarboxylic acid metabolism pathways, regulating the sugar and organic acid biosynthesis. Taste and nutrient differences could be revealed by variations in composition and abundance of carbohydrates, organic acids and amino acids. The purpose of this study was to provide a comprehensive chemical characterization of taste and nutrient compounds in 'Shushanggan apricot' fruits.


Assuntos
Prunus armeniaca , Ácidos/análise , Aminoácidos/metabolismo , Carboidratos/análise , Cromatografia Líquida , Ácido Cítrico/metabolismo , Frutas/química , Metabolômica , Sacarose/metabolismo , Espectrometria de Massas em Tandem , Paladar
15.
J Environ Sci (China) ; 117: 173-189, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35725069

RESUMO

The qualified finished water from water treatment plants (WTPs) may become discolored and deteriorated during transportation in drinking water distribution systems (DWDSs), which affected tap water quality seriously. This water stability problem often occurs due to pipe corrosion and the destabilization of corrosion scales. This paper provides a comprehensive review of pipe corrosion in DWDSs, including corrosion process, corrosion scale formation, influencing factors and monitoring technologies utilized in DWDSs. In terms of corrosion process, corrosion occurrence, development mechanisms, currently applied assays, and indices used to determine the corrosion possibility are summarized, as well as the chemical and bacterial influences. In terms of scale formation, explanations for the nature of corrosion and scale formation mechanisms are discussed and its typical multilayered structure is illustrated. Furthermore, the influences of water quality and microbial activity on scale transformation are comprehensively discussed. Corrosion-related bacteria at the genus level and their associated corrosion mechanism are also summarized. This review helps deepen the current understanding of pipe corrosion and scale formation in DWDSs, providing guidance for water supply utilities to ensure effective measures to maintain water quality stability and guarantee drinking water safety.


Assuntos
Água Potável , Ferro , Corrosão , Ferro/química , Qualidade da Água , Abastecimento de Água
16.
Conserv Biol ; 35(1): 316-324, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32839996

RESUMO

Very high-resolution (VHR) satellite sensors can be used to estimate the size of animal populations, a critical factor in wildlife management, and acquire animal spatial distributions in an economical, easy, and precise way. We developed a method for satellite population size estimation that includes a noninvasive photogrammetry, from which the animal's average orthographic area is calculated, and an imagery interpretation method that estimates population size based on the ratio of an observed animal population area to the average individual area. As a proof of concept, we used this method to estimate the population size of Whooper Swans (Cygnus cygnus) in a national nature reserve in China. To reduce errors, the reserve was subdivided into regions of interest based on locations of Whooper Swan and background brightness. Estimates from the satellite pixels were compared with manual counts made over 2 years, at 3 locations, and in 3 land-cover types. Our results showed 1124 Whooper Swans occupied a national nature reserve on 15 February 2013, and the average percent error was 3.16% (SE = 1.37). These results demonstrate that our method produced robust data for population size estimation that were indistinguishable from manual count data. Our method may be used generally to estimate population sizes of visible and gregarious animals that exhibit high contrast relative to their environments and may inform estimations of populations in complex backgrounds.


Estimación del Tamaño de las Poblaciones Animales Mediante Imágenes Satelitales de Muy Alta Resolución Resumen Los sensores satelitales de muy alta resolución (VHR) pueden utilizarse para estimar el tamaño de las poblaciones animales, un factor muy importante para el manejo de fauna, y para adquirir las distribuciones espaciales de los animales de una manera económica, sencilla y precisa. Desarrollamos un método para la estimación satelital del tamaño poblacional que incluye fotogrametría no invasiva, a partir de la cual se calcula el área ortogonal promedio del animal, y un método de interpretación de imágenes que estima el tamaño poblacional con base en la proporción del área poblacional observada de un animal con respecto al área individual promedio. Como demostración conceptual, usamos este método para estimar el tamaño poblacional del cisne trompetista (Cygnus cygnus) dentro de una reserva natural nacional en China. Para reducir los errores, subdividimos la reserva en regiones de interés con base en las ubicaciones de los cisnes y el brillo del fondo. Las estimaciones a partir de los pixeles satelitales fueron comparadas con los conteos manuales realizados a lo largo de dos años en tres ubicaciones y en tres tipos de cobertura de suelo. Nuestros resultados mostraron a 1124 cisnes ocupando una reserva natural nacional el 15 de febrero de 2013 y el error porcentual promedio fue de 3.15% (SE 1.37). Estos resultados demostraron que nuestro método produjo datos sólidos para la estimación del tamaño poblacional que eran indistinguibles de los datos obtenidos mediante el conteo manual. Nuestro método puede usarse de manera generalizada para estimar el tamaño poblacional de especies gregarias y visibles que exhiben un contraste alto en relación con su entorno y puede orientar las estimaciones de poblaciones con fondos complejos.


Assuntos
Conservação dos Recursos Naturais , Imagens de Satélites , Animais , Animais Selvagens , China , Densidade Demográfica
17.
J Craniofac Surg ; 32(5): 1762-1764, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33252519

RESUMO

ABSTRACT: Even though the pectoralis major myocutaneous flap (PMMF) still has an important role in the free flaps ear, it is reported to have drawbacks such as the limited cephalad extension and high incidence of total or partial flap necrosis. Various modifications have been attempted to augment the limited cephalad extension and a stable blood supply.The aim of this study is to describe a modified design of the skin paddle and preparation of the PMMF, to achieve stable blood circulation and sufficient pedicle length. The priority skin paddle is the medial part for its stable blood supply, and the lateral margin should be adjusted as needed. During the harvesting, the lateral thoracic artery (LTA) is preserved to protect the perforating branches, and the anterior sheath of the rectus abdominis muscle is used as a suture margin to prevent damage of the thin muscle of the PMMF. The skin paddles in this study are larger than those previously reported. All of the 21 patients in our study, the skin paddles show complete survival with no partial necrosis of skin paddle, fistula, or wound dehiscence.It is worthwhile to consider and preserve the LTA as a major contributor to a lateral and distal PMMF. This study would be useful in future and preparation of the PMMF in head and neck reconstruction.


Assuntos
Neoplasias de Cabeça e Pescoço , Retalho Miocutâneo , Procedimentos de Cirurgia Plástica , Humanos , Pescoço/cirurgia , Músculos Peitorais/transplante
18.
Nanotechnology ; 31(26): 265406, 2020 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-32155614

RESUMO

The shuttling-effect of soluble lithium-based polysulfides (LiPS) represents one of the main obstacles for practical application of lithium-sulfur (Li-S) batteries. Herein, to address this issue, a flexible Li-S interlayer consisting of a two-dimensional α-Co(OH)2 nano-plate and graphene oxide (GO) is developed using a simple vacuum filtration technique. In the interlayer, the α-Co(OH)2 and GO are assembled into a layered structure forming a physical barrier for the shuttling of LiPS. Additionally, the α-Co(OH)2 offers strong chemical adsorption and efficient catalysis performance towards LiPS conversion, further inhibiting its shuttling. Attributed to these beneficial features of the interlayer, the Li-S battery delivers an initial discharge capacity of 834 mAh g-1 at the current density of 1 C. More importantly, after 300 cycles, a high discharge capacity of 590 mAh g-1 was retained, corresponding to a low capacity fading rate of 0.1% per cycle. This work might be of great interest for the feasible and scalable preparation of multifunctional interlayers in Li-S batteries.

19.
J Oral Maxillofac Surg ; 78(1): 167-172, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31604061

RESUMO

PURPOSE: The aim was to evaluate the safety and efficacy of subcutaneous injection of hyaluronic acid in decreasing acute skin toxicity after adjuvant interstitial brachytherapy in parotid gland cancer patients. MATERIALS AND METHODS: Patients with histologically proven parotid gland cancer who would be treated with adjuvant interstitial brachytherapy were included in this nonrandomized controlled trial. Participants were nonrandomly divided into the experimental group and control group. Participants in the experimental group received an injection of hyaluronic acid subcutaneously immediately after interstitial brachytherapy during the operation. Acute toxicity was evaluated in the first 2 months. RESULTS: Thirty consecutive participants were included from April to September 2018. Twenty participants were in the experimental group, and 10 were in the control group. The median volume of hyaluronic acid was 8 mL (range, 4 to 11 mL). In total, the incidence of acute skin toxicity was 40% (8 of 20 patients) and 100% (10 of 10 patients) in the experimental group and control group, respectively. The difference in the dose delivered to 90% of the target volume of the affected skin was significant between the pre-plan (mean, 36.93 Gy) and the actuarial quality verification (mean, 27.70 Gy) in the experimental group (P = .004). The difference in scoring of acute skin toxicity was significant between the experimental and control groups (P = .001). No clear correlation was found between the dose delivered to 90% of the target volume of the affected skin and the scoring of acute skin toxicity (P = .266). CONCLUSIONS: Subcutaneous injection of hyaluronic acid was safe and efficient in decreasing acute skin toxicity after adjuvant interstitial brachytherapy in parotid gland cancer patients according to the preliminary results.


Assuntos
Braquiterapia , Neoplasias , Humanos , Ácido Hialurônico , Injeções Subcutâneas , Glândula Parótida , Dosagem Radioterapêutica
20.
J Environ Sci (China) ; 89: 218-226, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31892393

RESUMO

The current study analyzes the contribution of 10 water quality parameters (including pH, turbidity, conductivity, total dissolved solids (TDS), hardness, total organic carbon (TOC), alkalinity, calcium ions, chlorides and sulfates) to corrosion extent of stainless steel valves taken from different locations in a reverse osmosis system of a reclaimed water plant. The valves were in service for 5 years. Raman spectroscopy and X-ray photoelectron spectroscopy analyses are conducted to quantify corrosion products on different valves under various water quality conditions. On that basis, bivariate and multivariate regression analyses between the 10 water quality parameters and the corrosion extent of valve specimens (represented by metal loss percentage (MLP) values) are carried out to check the contribution of those water quality parameters to MLP. The results indicate that the proportions of metal oxides as corrosion products vary according to the corrosion extent of the valves. Although no linear correlation is found, all 10 water quality parameters except for pH show a significant positive correlation with the MLP values of the valve specimens. Moreover, results of multivariate regression suggest that the variation of MLP can be explained by turbidity, TDS, TOC and sulfates. A positive contribution of turbidity, TDS and TOC to MLP is observed, whereas the contribution of sulfates is negative. The results from the current work help to identify the reasons for water quality-induced failure of stainless steel equipment in RO systems.


Assuntos
Aço Inoxidável , Purificação da Água , Qualidade da Água , Corrosão , Osmose , Abastecimento de Água
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