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Extreme weather events have led to widespread yield losses and significant global economic damage in recent decades. African agriculture is particularly vulnerable due to its harsh environments and limited adaptation capacity. This systematic review analyzes 96 articles from Web of Science, Science Direct, and Google Scholar, focusing on biophysical studies related to maize in Africa and worldwide. We investigated the observed and projected extreme weather events in Africa, their impacts on maize production, and the approaches used to assess these effects. Our analysis reveals that drought, heatwaves, and floods are major threats to African maize production, impacting yields, suitable cultivation areas, and farmers' livelihoods. While studies have employed various methods, including field experiments, statistical models, and process-based modeling, African research is often limited by data gaps and technological constraints. We identify three main gaps: (i) lack of reliable long-term experimental and empirical data, (ii) limited access to advanced climate change adaptation technologies, and (iii) insufficient knowledge about specific extreme weather patterns and their interactions with management regimes. This review highlights the urgent need for targeted research in Africa to improve understanding of extreme weather impacts and formulate effective adaptation strategies. We advocate for focused research on data collection, technology transfer, and integration of local knowledge with new technologies to bolster maize resilience and food security in Africa.
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BACKGROUND: The fractures of proximal humerus have a high incidence in elderly patients, especially 3- or 4-part fracture. There are 4 main treatments including nonoperation, open reduction and internal fixation(ORIF), hemiarthroplasty(HA) and reverse shoulder arthroplasty(RSA). However, which one is the optimal choice remains a controversial topic. METHODS: Through the search of three electronic databases (PubMed, Embase, and Cochrane), the randomized controlled trials of 3- or 4-part proximal humeral fracture, until the end of July 2017, which is concerned with the elderly patients, were identified. The quality evaluation of each study was evaluated, Constant score and reoperation rates were extracted and analyzed. We used R(R i386 3.3.2) and the package of gemtc to perform our network meta-analysis. RESULTS: Seven randomized controlled experiments with a total number of 347 patients were brought into our network meta-analysis. The rank probability plot of Constant score showed that the RSA had significantly the highest Constant score and lower reoperation than other treatments. The other way around, the efficacy of ORIF was the poorest. The rank for the Constant score was: RSA, HA, nonoperation and ORIF. The rank for the reduction in total reoperation rates was: RSA, nonoperation, HA and ORIF. CONCLUSIONS: The statistical result suggested that RSA has become a beneficial choice to treat displaced 3-or 4-part fracture in elderly patients, that might result in more favorable clinical outcomes and reduction of reoperation rates than other methods performed for the same indication. But the ORIF is the worst.
Assuntos
Fraturas Múltiplas/terapia , Metanálise em Rede , Fraturas do Ombro/terapia , Idoso , Artroplastia do Ombro , Fixação Interna de Fraturas , Hemiartroplastia , Humanos , Imobilização , Redução Aberta , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
This study aimed to investigate the role of real-time B-mode ultrasound in posterior decompression and reduction and to observe the signal changes in spinal cord blood flow in a thoracolumbar burst fracture (TBF). Between February 2004 and December 2008, 138 patients with TBF were divided into group A (108 cases) and group B (30 cases). In group A, under the assistance of real-time B-mode ultrasound, posterior decompression and fracture piece reduction were performed, and we observed the signal changes in spinal cord blood flow. In group B, posterior fenestration was combined with pushing the fracture piece into the fractured vertebral body using an L-shaped operative tool. Presurgical and postsurgical recovery of neurological function was evaluated according to American Spinal Injury Association (ASIA) standards, and the range of spinal decompression was determined by measuring the proportion of encroached fracture piece in the spinal canal (spinal stenosis rate) on the computed tomography (CT) image. In group A, 12 patients had a grade A spinal injury according to the Frankel grading system, and there were six cases without neurological recovery. In the other patients, neurological function increased by 1-3 grades. There were no aggravated spinal cord injuries or other serious complications. In group B, three patients were categorized as grade A and there were two cases without neurological recovery. In the other patients, neurological function increased by 1-3 grades. In groups A and B, the postsurgical spinal stenosis rate was significantly lower than the presurgical stenosis rate (P<0.05). The postsurgical spinal stenosis rate in group B was significantly higher compared with group A (P<0.05). There was no significant difference in neurological function recovery between the groups (P>0.05). Real-time B-mode ultrasound is an effective method for posterior decompression and reduction and to observe signal changes in spinal cord blood flow in TBF.
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High levels of glucose in diabetics can react with plasma proteins through a non-enzymatic process. Herein, the influence of glucose on the interaction between flavones and human serum albumin (HSA) was investigated, as well as the effect of glucose on the antioxidant potential of a flavone-HSA system. It looks like the interactions of HSA and flavones with more hydroxyl groups on ring A are more easily affected by glucose. Flavones act as hydrogen bond donors with HSA by means of interacting with glucose. With increased incubation time in air (from 1 to 23 days), the affinities of HSA for multi-hydroxyl flavones on ring A were obviously higher than for non- or mono-hydroxyl flavones on ring A. HSA significantly masked the DPPH radical scavenging potential of 7,8-dihydroxyflavone and baicalein. However, glucose obviously enhances the DPPH scavenging potential of a baicalein-HSA system. Moreover, glucose slightly weakens the DPPH scavenging potential of a 7,8-dihydroxyflavone-HSA system.