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121.
Abstract

The incidence of insect pests in cotton crop, such as Bemisia tabaci, Amrasca devastans and Pectinophora gossypiella (PBW) is dependent on climatic factors, such as maximum and minimum temperature, relative humidity and rainfall. Besides, cotton leaf curl disease (CLCuD) is also a major yield-limiting factor in the cotton crop. The results indicated that non-transgenic genotypes were heavily infested by whitefly, whereas jassid infested all genotypes with little difference. The population of whitefly and jassid acquired peak level in the month of July and August on all the genotypes. The correlation studies indicated the negative correlation of jassid, pink bollworm and CLCuD on yield component, whereas whitefly infestation was found positively correlated with CLCuD. Moreover, multivariate regression analysis (MRA) indicated the maximum and minimum temperature impacted the infestation of whitefly and jassid more than other factors, whereas maximum temperature greatly impacted the infestation of PBW in transgenic genotypes.  相似文献   
122.
Independent navigation for blind individuals can be extremely difficult due to the inability to recognise and avoid obstacles. Assistive techniques such as white canes, guide dogs, and sensory substitution provide a degree of situational awareness by relying on touch or hearing but as yet there are no techniques that attempt to make use of any residual vision that the individual is likely to retain. Residual vision can restricted to the awareness of the orientation of a light source, and hence any information presented on a wearable display would have to limited and unambiguous. For improved situational awareness, i.e. for the detection of obstacles, displaying the size and position of nearby objects, rather than including finer surface details may be sufficient. To test whether a depth-based display could be used to navigate a small obstacle course, we built a real-time head-mounted display with a depth camera and software to detect the distance to nearby objects. Distance was represented as brightness on a low-resolution display positioned close to the eyes without the benefit focussing optics. A set of sighted participants were monitored as they learned to use this display to navigate the course. All were able to do so, and time and velocity rapidly improved with practise with no increase in the number of collisions. In a second experiment a cohort of severely sight-impaired individuals of varying aetiologies performed a search task using a similar low-resolution head-mounted display. The majority of participants were able to use the display to respond to objects in their central and peripheral fields at a similar rate to sighted controls. We conclude that the skill to use a depth-based display for obstacle avoidance can be rapidly acquired and the simplified nature of the display may appropriate for the development of an aid for sight-impaired individuals.  相似文献   
123.
Abstract

Herein, we report the DNA interaction studies of rhenium(I) and -(V) compounds with Schiff base chelates encompassing biologically relevant moieties. More specifically, the DNA interaction capabilities of these rhenium complexes were probed using Gel Electrophoresis and Calf Thymus–DNA titrations monitored by temperature-controlled electronic spectroscopy. The DNA binding modes of the metal compounds were corroborated by molecular docking simulations. In addition, the synthesis and characterization of a novel facial tricarbonyl rhenium(I) compound, fac-[Re(chrs)(CO)3Br], (chrs = {3-{[(2-hydroxyphenyl)imino]methyl}-4H-chromen-4-one) are reported.  相似文献   
124.
Measuring similarities between objects based on their attributes has been an important problem in many disciplines. Object-attribute associations can be depicted as links on a bipartite graph. A similarity measure can be thought as a unipartite projection of this bipartite graph. The most widely used bipartite projection techniques make assumptions that are not often fulfilled in real life systems, or have the focus on the bipartite connections more than on the unipartite connections. Here, we define a new similarity measure that utilizes a practical procedure to extract unipartite graphs without making a priori assumptions about underlying distributions. Our similarity measure captures the relatedness between two objects via the likelihood of a random walker passing through these nodes sequentially on the bipartite graph. An important aspect of the method is that it is robust to heterogeneous bipartite structures and it controls for the transitivity similarity, avoiding the creation of unrealistic homogeneous degree distributions in the resulting unipartite graphs. We test this method using real world examples and compare the obtained results with alternative similarity measures, by validating the actual and orthogonal relations between the entities.  相似文献   
125.

Objective

To evaluate the coverage and timeliness of the Expanded Programme on Immunisation (EPI) in The Gambia.

Methods

Vaccination data were obtained between January 2005 and December 2012 from the Farafenni Health and Demographic Surveillance System (FHDSS), the Basse Health and Demographic Surveillance System (BHDSS), the Kiang West Demographic surveillance system (KWDSS), a cluster survey in the more urban Western Health Region (WR) and a cross sectional study in four clinics in the semi-urban Greater Banjul area of WR. Kaplan-Meier survival function was used to estimate the proportion vaccinated by age and to assess timeliness to vaccination.

Findings

BCG vaccine uptake was over 95% in all regions. Coverage of DPT1 ranged from 93.2% in BHDSS to 99.8% in the WR. Coverage decreased with increasing number of DPT doses; DPT3 coverage ranged from 81.7% in BHDSS to 99.0% in WR. Measles vaccination coverage ranged from 83.3% in BHDSS to 97.0% in WR. DPT4 booster coverage was low and ranged from 43.9% in the WR to 82.8% in KWDSS. Across all regions, delaying on previous vaccinations increased the likelihood of being delayed for the subsequent vaccination.

Conclusions

The Gambia health system achieves high vaccine coverage in the first year of life. However, there continues to be a delay to vaccination which may impact on the introduction of new vaccines. Examples of effectively functioning EPI programmes such as The Gambia one may well be important models for other low income countries struggling to achieve high routine vaccination coverage.  相似文献   
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128.
Data providing direct evidence for a causative link between endothelial dysfunction, microvascular disease and diabetic end-organ damage are scarce. Here we show that activated protein C (APC) formation, which is regulated by endothelial thrombomodulin, is reduced in diabetic mice and causally linked to nephropathy. Thrombomodulin-dependent APC formation mediates cytoprotection in diabetic nephropathy by inhibiting glomerular apoptosis. APC prevents glucose-induced apoptosis in endothelial cells and podocytes, the cellular components of the glomerular filtration barrier. APC modulates the mitochondrial apoptosis pathway via the protease-activated receptor PAR-1 and the endothelial protein C receptor EPCR in glucose-stressed cells. These experiments establish a new pathway, in which hyperglycemia impairs endothelial thrombomodulin-dependent APC formation. Loss of thrombomodulin-dependent APC formation interrupts cross-talk between the vascular compartment and podocytes, causing glomerular apoptosis and diabetic nephropathy. Conversely, maintaining high APC levels during long-term diabetes protects against diabetic nephropathy.  相似文献   
129.
Influenza A subtype H5N1 has represented a growing alarm since its recent identification in Asia. Previously thought to infect only wild birds and poultry, H5N1 has now infected humans, cats, pigs and other mammals in an ongoing outbreak, often with a fatal outcome. In order to evaluate the risk factors for human infection with influenza virus H5N1, here we summarize 53 case patients confirmed with H5N1 infection during 2006. The review also compares the mortality rate among human cases from late 2003 until 15 June 2006 in different countries. Neither how these viruses are transmitted to humans nor the most effective way to reduce the risk for infection is fully understood. The association between household contact with diseased poultry in human infection has been demonstrated. This association could possibly operate by 2 mechanisms. First, transmission may be by inhalation or conjunctival deposition of large infectious droplets which may travel only in short distances. Second, having infected poultry in the home and preparation of infected poultry for consumption may result in exposure to higher virus concentrations than other types of exposure. There is so far no significant evidence for repeated human to human transmission, yet some cases of human to human transmission among the family relatives in Indonesia, Azerbaijan, Iraq and Turkey have been described. Recent outbreaks of highly pathogenic avian influenza A virus (H5N1 subtype) infections in poultry and humans (through direct contact with infected birds) have raised concerns that a new influenza pandemic might occur in the near future.  相似文献   
130.
This study aimed to investigate the effect of curcumin (CUR) on doxorubicin (DOX)‐induced testicular damage in male rats. Thirty‐five adult male Wistar rats were used. Control group was received saline for 7 days. CUR group received CUR for 7 days. DOX group received single dose DOX on the 5th day. DOX+ CUR‐100 group received 100 mg/kg/day CUR for 7 days and DOX injection on the 5th day. DOX + CUR‐200 group received 200 mg/kg/day CUR for 7 days and DOX injection on the 5th day. DOX treatment decreased in sperm motility rate, live sperm percentages, cellular antioxidants, and increased malondialdehyde (MDA) levels, necrosis, degenerations, and slimming in seminiferous tubules, and DNA damages in testes by inducing oxidative stress. CUR treatment mitigated significantly these side effects when compared with DOX group in a dose‐dependent manner. In conclusion, CUR treatment can be used in the mitigation of DOX‐induced testicular toxicity.  相似文献   
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