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Early seed development is vital for plant reproduction, but the processes behind this in gymnosperms like Torreya grandis, which has a low rate of normal early-developed seeds, are not well understood. To fill this knowledge gap, we embarked on a comprehensive investigation encompassing the morphology and phenology of seed development in T. grandis. Using the 13C labelling analysis, coupled with leaf removal and seed thinning treatments, we observed a substantial increase in the content of photo-assimilate, an almost 10% increase in sucrose content under seed thinning treatments, thereby leading to an increase in the proportion of normal early-developed seeds, reaching 15%. Concurrently, through the integration of multi-omics analyses and transient overexpression validation, we identified cell wall invertase coding gene, TgCWIN2, which plays a pivotal role in sucrose cleavage during the early development of T. grandis seeds. Further gene co-expression, dual-luciferase assay, and yeast one-hybrid assay revealed that TgWRKY31 was a candidate regulator of TgCWIN2, positively influencing its expression by direct binding to the TgCWIN2 promoter. Notably, TgWRKY31 transient overexpression substantially enhances the expression of TgCWIN2, thereby contributing to a higher proportion of normal early-developed seeds. Our findings not only provide a comprehensive understanding of the underlying mechanisms governing the early development of T. grandis seeds, but are also essential for establishing strategies to enhance early seed development and improve yield.
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Urban expansion has the potentiality to disrupt ecosystems and form highly fragile urban landscapes. However, studies investigating the impact of different urban expansion patterns on the ecological environments are relatively limited. Taking the Yanhe river basin, a typical basin in a loess region, as a case study, we developed an ecological vulnerability assessment system as well as assessed the main drivers of ecological vulnerability for different time periods (1990, 2000, 2010 and 2018). Additionally, we classified each urban expansion region into three different patterns according to the landscape expansion index, and analyzed changes in the ecological vulnerability under these three diverse patterns. Finally, the Kruskal-Wallis rank sum test was applied to compare the factors for the different changes in ecological vulnerability across different urban expansion patterns. Our investigation also aimed to elucidate the impacts of different urban expansion patterns on ecological vulnerability and identify key physical-social-economic-climatic drivers. The results indicate that the ecological vulnerability index (EVI) of the study area is decreasing gradually from the peak value of 0.459 in 2000 to 0.383 in 2018. Habitat quality index is found to be the most influencing factor, followed by aridity index and building density (mean q of 0.53, 0.46, and 0.42, respectively). Our study also reveals that the outlying expansion areas have the greatest increase in EVI at 0.38, with edge and infill expansions at 0.31 and 0.27, respectively. It is also found that when the overall environment is improving, the outlying expansion areas have the smallest decrease in EVI. Initial ecological vulnerability and key drivers may explain this difference. Therefore, results of this study indicate that the ecological impacts of diverse urban expansion patterns are significantly different, among which outlying expansions should receive prioritized attention.
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INTRODUCTION: There is uncertainty and lack of consensus regarding optimal management of patent ductus arteriosus (PDA). We aimed to determine current clinical practice in PDA management across a range of different regions internationally. MATERIALS AND METHODS: We surveyed PDA management practices in neonatal intensive care units using a pre-piloted web-based survey, which was distributed to perinatal societies in 31 countries. The survey was available online from March 2018 to March 2019. RESULTS: There were 812 responses. The majority of clinicians (54%) did not have institutional protocols for PDA treatment, and 42% reported variable management within their own unit. Among infants <28 weeks (or <1,000 g), most clinicians (60%) treat symptomatically. Respondents in Australasia were more likely to treat PDA pre-symptomatically (44% vs. 18% all countries [OR 4.1; 95% CI 2.6-6.5; p < 0.001]), and respondents from North America were more likely to treat symptomatic PDA (67% vs. 60% all countries [OR 2.0; 95% CI 1.5-2.6; p < 0.001]). In infants ≥28 weeks (or ≥1,000 g), most clinicians (54%) treat symptomatically. Respondents in North America were more likely to treat PDAs in this group of infants conservatively (47% vs. 38% all countries [OR 2.3; 95% CI 1.7-3.2; p < 0.001]), and respondents from Asia were more likely to treat the PDA pre-symptomatically (21% vs. 7% all countries [OR 5.5; 95% CI 3.2-9.8; p < 0.001]). DISCUSSION/CONCLUSION: There were marked international differences in clinical practice, highlighting ongoing uncertainty and a lack of consensus regarding PDA management. An international conglomeration to coordinate research that prioritises and addresses these areas of contention is indicated.
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Conducto Arterioso Permeable , Unidades de Cuidado Intensivo Neonatal , Pautas de la Práctica en Medicina , Conducto Arterioso Permeable/terapia , Humanos , Recién Nacido , Pautas de la Práctica en Medicina/estadística & datos numéricos , Encuestas y Cuestionarios , Unidades de Cuidado Intensivo Neonatal/estadística & datos numéricos , Recien Nacido Prematuro , América del Norte , Encuestas de Atención de la Salud , Femenino , Australasia , InternetRESUMEN
BACKGROUND: Despite the known clinical benefits of continuous positive airway pressure (CPAP) to support preterm infants breathing, there are limited studies that have examined its effect on regional oxygenation. OBJECTIVES: This study aimed to investigate how the application of CPAP affects cerebral and splanchnic tissue oxygenation in preterm infants. METHODS: A pilot observational study was conducted in infants using near-infrared spectroscopy while off CPAP and on CPAP. Regional cerebral and splanchnic saturations and variability (coefficient of variability; CV) were evaluated. RESULTS: Twenty-six infants (25-37 weeks gestational age at birth) were studied. The mean cerebral oxygenation did not differ with the application of CPAP (80 ± 4.2% without CPAP; 80 ± 1.9% with CPAP), but variability around the mean was less with CPAP (CV 5 vs. 2%, respectively). Mean cerebral fractional oxygen extraction (FOE) increased with CPAP from 0.13 ± 0.06 to 0.17 ± 0.04% (p = 0.002). Splanchnic oxygenation increased significantly from 66 ± 11.6 to 75 ± 9.1% with CPAP (p < 0.001) and also became more stable (CV 13 vs. 7%, respectively). Splanchnic FOE decreased with CPAP from 0.28 ± 0.13 to 0.22 ± 0.10% (p = 0.002). CONCLUSION: The application of CPAP did not affect mean cerebral oxygenation in this group of preterm and term infants; however, it led to a significant increase in splanchnic oxygenation. These findings highlight the important role that respiratory support may play in maintaining adequate and stable oxygen delivery to vital organs.
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Circulación Cerebrovascular , Presión de las Vías Aéreas Positiva Contínua , Enfermedades del Prematuro/terapia , Oxígeno/sangre , Circulación Esplácnica , Femenino , Edad Gestacional , Humanos , Recién Nacido , Recien Nacido Prematuro , Masculino , Consumo de Oxígeno , Proyectos Piloto , Espectroscopía Infrarroja CortaRESUMEN
A nonlinear model of consistency with derivative absorption in multiple components systems has been given. Model data were estimated by partial least squares method. A method for the simultaneous derivative spectrophotometric determination of two components with nonlinear partial least squares method was established. The method has been applied to the simultaneous determination of two components in compound sulfamethoxazole tablets. The average recoveries of sulfamethoxazole and trimethoprim in synthetic samples were 99.8% and 100.1%, and relative standard deviations were 1.3% and 1.6%, respectively. The results by nonlinear PLS method are significantly better than those by linear PLS method. The results for actual compound formulation agreed with those obtained by standard method.