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Introduction: Moso bamboo forests, widely distributed in subtropical regions, are increasingly valued for their strong carbon sequestration capacity. However, the carbon flux variations and the driving mechanisms of Moso bamboo forest ecosystems of each phenology period have not been adequately explained. Methods: Hence, this study utilizes comprehensive observational data from a Moso bamboo forest eddy covariance observation for the full phenological cycle (2011-2015), fitting a light response equation to elucidate the evolving dynamics of carbon fluxes and photosynthetic characteristics throughout the entire phenological cycle, and employing correlation and path analysis to reveal the response mechanisms of carbon fluxes to both biotic and abiotic factors. Results: The results showed that, First, the net ecosystem exchange (NEE) of Moso bamboo forest exhibits significant variations across six phenological periods, with LSOFF demonstrating the highest NEE at -23.85 ± 12.61 gC·m-2·5day-1, followed by LSON at -19.04 ± 11.77 gC·m-2·5day-1 and FGON at -17.30 ± 9.58 gC·m-2·5day-1, while NFOFF have the lowest value with 3.37 ± 8.24 gC·m-2·5day-1. Second, the maximum net photosynthetic rate (Pmax) and apparent quantum efficiency (α) fluctuated from 0.42 ± 0.20 (FGON) to 0.75 ± 0.24 mg·m-2·s-1 (NFOFF) and from 2.3 ± 1.3 (NFOFF) to 3.3 ± 1.8 µg·µmol-1 (LSOFF), respectively. Third, based on the path analysis, soil temperature was the most important driving factor of photosynthetic rate and NEE variation, with path coefficient 0.81 and 0.55, respectively, followed by leaf area index (LAI), air temperature, and vapor pressure difference, and precipitation. Finally, interannually, increased LAI demonstrated the potential to enhance the carbon sequestration capability of Moso bamboo forests, particularly in off-years, with the highest correlation coefficient with NEE (-0.59) among the six factors. Discussion: The results provide a scientific basis for carbon sink assessment of Moso bamboo forests and provide a reference for developing Moso bamboo forest management strategies.
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Surface engineering in perovskite solar cells, especially for the upper surface of perovskite, is widely studied. However, most of these studies have primarily focused on the interaction between additive functional groups and perovskite point defects, neglecting the influence of other parts of additive molecules. Herein, additives with -NH3 + functional group are introduced at the perovskite surface to suppress surface defects. The chain lengths of these additives vary to conduct a detailed investigation into the impact of molecular size. The results indicate that the propane-1,3-diamine dihydroiodide (PDAI2 ), which possesses the most suitable size, exhibited obvious optimization effects. Whereas the molecules, methylenediamine dihydroiodide (MDAI2 ) and pentane-1,5-diamine dihydroiodide (PentDAI2 ) with unsuitable size, lead to a deterioration in device performance. The PDAI2 -treated devices achieved a certified power conversion efficiency (PCE) of 25.81% and the unencapsulated devices retained over 80% of their initial PCE after 600 h AM1.5 illumination.
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Net primary productivity (NPP) is an important indicator used to evaluate the carbon sequestration capacity of forest ecosystems. Subtropical forest ecosystems play an indispensable role in maintaining the global carbon balance, while frequently occurring drought events in recent years have seriously damaged their productivity. However, the spatiotemporal patterns of NPP, as well as its response to drought, remain uncertain. In this study, the multiscale drought characteristics in subtropical China during 1981-2015 were analyzed based on the standardized precipitation evapotranspiration index. Then, simulated and analyzed the spatiotemporal NPP of subtropical forests by the boreal ecosystem productivity simulator model. Finally, the response of NPP to drought was analyzed based on multiple statistical indices. The results show that most regions in subtropical China experienced mild and moderate drought during 1981-2015. In particular, the extent of drought severity has shown a noticeable increasing trend after 2000. The forest NPP ranged from 622.64 to 1323.82 gC·m-2·a-1, with an overall increase rate of 16.15 gC·m-2·a-1; in particular, the contribution of the western forest NPP became increasingly important. Drought stress has limited the growth of subtropical forest NPP in China, with summer and wet season time scales of drought having the greatest impact on forest NPP anomalies, followed by autumn time scales. The limitation is mostly because the drought duration continually increased, leading to differences in the impact of drought on forest NPP before and after 2000, with declines of 59.55 % and 82.45 %, respectively, mainly concentrated in southwestern regions, such as Yunnan, Guangxi, and Sichuan provinces. This study quantitatively analyzed the impact of drought on subtropical forest NPP, and provides scientific basis for subtropical forest response and adaptation to climate change.
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Sequías , Ecosistema , China , Bosques , Incertidumbre , Cambio ClimáticoRESUMEN
INTRODUCTION: Stress urinary incontinence (SUI) occurs due to disruption of the pelvic floor anatomy; however, the complexity of the pelvic floor support structures and individual patient differences make it difficult to identify the weak points in the pelvic floor support that cause SUI to occur, develop, and recur. This study aimed to analyze the pelvic floor anatomy, structural features, and biomechanics of cystoceles to develop more effective treatment plans with individualized and precise healthcare. MATERIAL AND METHODS: In this observational case-controlled study (clinical trial identifier BOJI201855L), 102 women with normal pelvic floor function and 273 patients diagnosed with cystocele degrees I-III were identified at Shanghai General Hospital from October 2016 to December 2019. We combined ultrasound and vaginal tactile imaging (VTI) to assess the anatomy and biomechanical functions of the anterior and posterior vaginal walls. Both examinations included relaxation and muscle tension tests. RESULTS: Of the 42 VTI parameters, 13 were associated with the degree of cystocele, six with an increase in the urethral rotation angle (pointing to the mobility of the urethra), and six with a decrease in the retrovesical angle (pointing to hypsokinesis and decrease in bladder position). According to these data, the strength of tissues, especially the muscles in both the anterior and posterior compartments, contributes to the stability of the pelvic floor structure. The strength of the levator ani muscle (LAM) is important for the degree of cystocele, mobility of the urethra, hypsokinesis, and decrease in bladder position. CONCLUSIONS: In general, the biomechanical status of the pelvic floor in patients with cystocele is complex and involves various muscles, ligaments, tendons, and fascia. Of these, repair and exercise of the LAM have not received much attention in the treatment of patients with cystoceles, which may be an important risk factor for the high recurrence rate.
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Cistocele , Incontinencia Urinaria de Esfuerzo , Femenino , Humanos , China , Cistocele/diagnóstico por imagen , Cistocele/complicaciones , Diafragma Pélvico/diagnóstico por imagen , Vejiga Urinaria , Incontinencia Urinaria de Esfuerzo/diagnóstico por imagen , Incontinencia Urinaria de Esfuerzo/etiología , Estudios de Casos y ControlesRESUMEN
Subtropical forests are rich in vegetation and have high photosynthetic capacity. China is an important area for the distribution of subtropical forests, evergreen broadleaf forests (EBFs) and evergreen needleleaf forests (ENFs) are two typical vegetation types in subtropical China. Forest carbon storage is an important indicator for measuring the basic characteristics of forest ecosystems and is of great significance for maintaining the global carbon balance. Drought can affect forest activity and may even lead to forest death and the stability characteristics of different forest ecosystems varied after drought events. Therefore, this study used meteorological data to simulate the standardized precipitation evapotranspiration index (SPEI) and the Biome-BGC model to simulate two types of forest carbon storage to quantify the resistance and resilience of EBF and ENF to drought in the subtropical region of China. The results show that: 1) from 1952 to 2019, the interannual drought in subtropical China showed an increasing trend, with five extreme droughts recorded, of which 2011 was the most severe one; 2) the simulated average carbon storage of the EBF and ENF during 1985-2019 were 130.58 t·hm-2 and 78.49 t·hm-2, respectively. The regions with higher carbon storage of EBF were mainly concentrated in central and southeastern subtropics, where those of ENF mainly distributed in the western subtropic; 3) The median of resistance of EBF was three times higher than that of ENF, indicating the EBF have stronger resistance to extreme drought than ENF. Moreover, the resilience of two typical forest to 2011 extreme drought and the continuous drought events during 2009 - 2011 were similar. The results provided a scientific basis for the response of subtropical forests to drought, and indicating that improve stand quality or expand the plantation of EBF may enhance the resistance to drought in subtropical China, which provided certain reference for forest protection and management under the increasing frequency of drought events in the future.
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Through field investigation, UPLC-MS/MS technology and MaxEnt model were performed to predict the suitable distribution area for red huajiao (Zanthoxylum bungeanum maxim.) in China from 2021 s to 2060 s, and evaluate the effects of climate factors on the quality of red huajiao. The results demonstrated that mean temperature of the coldest quarter and min temperature of the coldest month were the most important environmental variables influencing red huajiao distribution. Suitable habitats for red huajiao were located mainly in dry and hot valley zone in the Qinba Mountains and the semi-humid and semi-arid areas of the Loess Plateau. The amides contents were higher in high suitability areas, while it was decreased in medium and low suitability areas, and temperature, wind speed and precipitation played a key role in their accumulation. This investigation was of great significance for the planting area optimization, quality control, benefit improvement and industrial development of red huajiao.
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Zanthoxylum bungeanum Maxim. as an important economic forest, its epidermis bears prickles which complicate the harvesting process and increase the labor costs. To explore the developmental mechanism of prickles, three varieties of Zanthoxylum bungeanum (PZB, SZB, GSZB) were selected for morphological and multi-omics analyses. The absorption spectra of prickles and stems were detected using Fourier-transform infrared spectroscopy (FTIR), and they were found different at 1617, 1110, 3319, and 1999 cm-1. The morphology of prickles and stems were observed using light microscopy and transmission electron microscopy (TEM). The growth direction of cells on the prickle side and stem side were perpendicular to each other, and there was a resembling abscission zone (RAZ) between them. The vacuolar deposits of prickle cells were much more than stem cells, indicating that the lignification degree of prickles was higher than stems. In addition, 9 candidate genes (ZbYABBY2, ZbYABBY1, ZbYABBY5, ZbWRKY, ZbLOG5, ZbAZG2, ZbGh16, ZbIAA33, and ZbGh16X1) were screened out and validated base on transcriptome and qRT-PCA. As well as, 30 key metabolites were found related to prickle development base on metabolome analysis. Among them, 4-hydroxy-2-oxopentanoate, trans-2-hydroxy-cinnamate, trans-cinnamate, polyhydroxy-fatty acid, 10,16-dihydroxypalmitate, cinnamic acid were related to the biosynthesis of cutin, suberine and wax. Indole-3-acetate, tryptamine, anthranilate, fromylanthranilate, N6-(delta2-isopentenyl)-adenine were related to plant hormone signal transduction. Generally, this is the first study to reveal the developmental mechanism of prickles. The results of this study lay the foundation for the breeding of non-prickle Zanthoxylum bungeanum.
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Hydroxyl radicals (â¢OH) are important reactive species that are photochemically generated through solar irradiation of chromophoric dissolved organic matter (CDOM) in surface waters. However, the spatial distribution within the complex three-dimensional structure of CDOM has not been examined. In this study, we used a series of hydrophobic chlorinated paraffins as chemical probes to elucidate the microheterogeneous distribution of â¢OH in illuminated CDOM solutions. The steady-state concentration of â¢OH inside the CDOM microphase is 210 ± 31-fold higher than the concentration in the aqueous phase. Our results suggest that the most photochemically generated â¢OH are confined into the CDOM microphase. Thus, illuminated CDOM behaves as a natural microreactor for â¢OH-based oxidations. By including intra-CDOM â¢OH, the quantum yield of â¢OH for CDOM solutions was estimated to be 2.2 ± 0.5 × 10-3, which is 2 orders of magnitude greater than previously thought. The elevated concentrations of photogenerated â¢OH within the CDOM microphase may improve the understanding of hydrophobic pollutant degradation in aqueous environments. Moreover, our results also suggest that â¢OH oxidation may play more important roles in the phototransformation of CDOM than previously expected.
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Radical Hidroxilo , Procesos Fotoquímicos , Oxidación-Reducción , Fenómenos Físicos , AguaRESUMEN
[This corrects the article DOI: 10.3389/fpubh.2020.589359.].
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This review summarizes the recent research on nitride nanostructures and their applications. We cover recent advances in the synthesis and growth of porous structures and low-dimensional nitride nanostructures via metal-assisted photochemical etching and molecular beam epitaxy. The growth of nitride materials on various substrates, which improves their crystal quality, doping efficiency, and flexibility of tuning performance, is discussed in detail. Furthermore, the recent development of In(Ga)N nanostructure applications (light-emitting diodes, lasers, and gas sensors) is presented. Finally, the challenges and directions in this field are addressed.
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Although it is known that the solar irradiation of chromophoric dissolved organic matter (CDOM) solutions generates H2O2, whether or not organic hydroperoxides (ROOHs) are photochemically formed remains unclear. This study employs high-performance liquid chromatography with the postcolumn enzymatic derivatization method to examine whether ROOHs can be formed in CDOM solutions under simulated solar irradiation. Methylhydroperoxide (MHP) is the only identified ROOH under our experimental conditions, and the quantum yields of MHP (ΦMHP) vary from (1.09 ± 0.09) × 10-6 to (4.95 ± 0.11) × 10-6 in the tested CDOM solutions, including four reference natural organic matters and two effluent organic matters. The quantum yields of H2O2 (ΦH2O2) are simultaneously measured, and the ratios of ΦH2O2 to ΦMHP range from 147 to 676. The formation of MHP is highly related to the presence of superoxide radical ions (O2â¢-) and methyl radicals (CH3â¢); therefore, a photoformation mechanism of MHP has been proposed. The photochemically generated CH3⢠reacts with O2 to yield CH3OOâ¢. Subsequently, CH3OO⢠is reduced to MHP by O2â¢-. Our results also suggest that the yield of CH3⢠to MHP under air-saturated conditions is 52% and increases to 98% under oxygen-saturated conditions. The decays of MHP and H2O2 are very similar in terms of photodegradation, hydrolysis, Fenton, and photo-Fenton reactions. This study can be useful to understand the photochemical formation of organic peroxides in surface waters.
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Peróxido de Hidrógeno , Procesos Fotoquímicos , Peróxidos , Fenómenos Físicos , SuperóxidosRESUMEN
This study aimed to evaluate the psychological effects of the partial lockdown on the people in Vietnam during the COVID-19 pandemic. An online questionnaire regarding attitudes toward COVID-19 along with psychological parameters, including the Impact of Event Scale-Revised (IES-R) Depression, Anxiety, Stress Scale-21 (DASS-21) was conducted. From a total of 1,382 questionnaires, the respondents reported low prevalence of depression (4.9%), anxiety (7.0%), and stress (3.4%). The mean DASS-21 scores recorded were also markedly lower compared to similar studies conducted in China, Italy, and Iran. Respondents who reported severe PTSD had significantly higher depression, anxiety, and stress levels. Factors that were associated with an increased level of depression, stress, and anxiety were being single, separated, or widowed, a higher education level, a larger family size, loss of jobs and being in contact with potential COVID-19 patients. Contrary to expectations, the level of depression, stress, and anxiety observed has been low. Our findings can aid in future research on the impact of a partial lockdown and guide mental health professionals in Vietnam and other countries in the preparation of better care for populations under such circumstances.
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COVID-19 , Pandemias , Ansiedad/epidemiología , China , Control de Enfermedades Transmisibles , Depresión/epidemiología , Humanos , Irán , Italia , Salud Mental , SARS-CoV-2 , Estrés Psicológico/epidemiología , Vietnam/epidemiologíaRESUMEN
This study aimed to assess and compare the immediate stress and psychological impact experienced by people with and without psychiatric illnesses during the peak of 2019 coronavirus disease (COVID-19) epidemic with strict lockdown measures. Seventy-six psychiatric patients and 109 healthy control subjects were recruited from Chongqing, China and completed a survey on demographic data, physical symptoms during the past 14 days and a range of psychiatric symptoms using the Impact of Event Scale-Revised (IES-R), Depression, Anxiety and Stress Scale (DASS-21) and Insomnia Severity Index (ISI). IES-R measures PTSD symptoms in survivorship after an event. DASS-21 is based on tripartite model of psychopathology that comprise a general distress construct with distinct characteristics. The mean IES-R, DASS-21 anxiety, depression and stress subscale and ISI scores were higher in psychiatric patients than healthy controls (p < 0.001). Serious worries about their physical health, anger and impulsivity and intense suicidal ideation were significantly higher in psychiatric patients than healthy controls (p < 0.05). More than one-third of psychiatric patients might fulfil the diagnostic criteria post-traumatic stress disorder (PTSD). More than one-quarter of psychiatric patients suffered from moderately severe to severe insomnia. Respondents who reported no change, poor or worse physical health status and had a psychiatric illness were significantly more likely to have higher mean IES-R, DASS depression, anxiety and stress subscale scores and ISI scores (p < 0.05). This study confirms the severity of negative psychological impact on psychiatric patients during the COVID-19 epidemic with strict lockdown measures. Understanding the psychological impact on psychiatric patients during the COVID-19 pandemic has the potential to provide insight into how to develop a new immunopsychiatry service. Further research is required to compare pro-inflammatory cytokines between psychiatric patients and healthy controls during the pandemic.
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Infecciones por Coronavirus/psicología , Depresión/psicología , Neumonía Viral/psicología , Adulto , Ansiedad/epidemiología , Ansiedad/psicología , Trastornos de Ansiedad/epidemiología , Trastornos de Ansiedad/psicología , Betacoronavirus , COVID-19 , Estudios de Casos y Controles , China , Coronavirus , Depresión/epidemiología , Femenino , Estado de Salud , Humanos , Masculino , Trastornos Mentales/psicología , Persona de Mediana Edad , Pandemias , Psiconeuroinmunología , SARS-CoV-2 , Trastornos del Inicio y del Mantenimiento del Sueño/psicología , Trastornos por Estrés Postraumático/epidemiología , Trastornos por Estrés Postraumático/psicología , Estrés Psicológico/psicología , Encuestas y CuestionariosRESUMEN
Multiple osteochondroma (MO) is an autosomal dominant disease characterized by abnormal skeleton development: one or more exostoses localized mainly at the end of long bones. Three pathogenic gene loci have been identified and cloned: EXT1, 2, and 3. Only EXT1 and 2 mutations were reported to cause MO. Here, we report on a large Chinese family with MO and a disease-causing mutation in EXT. We extracted DNA from peripheral blood samples of 25 family members, 9 with MO. Polymerase chain reaction and direct DNA sequencing of the entire coding regions of EXT1 and 2 for the nine patients revealed a novel pathogenic mutation, insertion of a T in exon 2 (c.72-73 insT) of EXT2. Our results extend the mutational spectrum of MO and can help with genetic counseling and prenatal diagnosis for this family.
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Exostosis Múltiple Hereditaria/genética , Genes Relacionados con las Neoplasias , Sitios Genéticos , Mutación , Adulto , Pueblo Asiatico , China , Análisis Mutacional de ADN/métodos , Familia , Femenino , Humanos , Masculino , N-Acetilglucosaminiltransferasas/genética , Proteínas de Neoplasias/genética , Linaje , Reacción en Cadena de la Polimerasa/métodosRESUMEN
OBJECTIVE: To explore the effect of the tri-cuff vascular anastomosis for simplifying the surgical procedure and improving the success rate. METHOD: Sixty recipient Wistar rats were randomized into experimental group and the control group, the former was subjected to the tri-cuff vascular anastomosis for heterotopic small bowel transplantation while the latter had vascular anastomosis using classical methods. The effects of the two methods for anastomosis were compared. RESULTS: The tri-cuff vascular anastomosis was superior to the classical methods in view of the total operation time, arterial anastomosis time, and hot-ischemia time of the small bowel graft. CONCLUSION: Compared with the classical methods, the tri-cuff vascular anastomosis is safer and time-saving.