UAV-Assisted Dynamic Clustering of Wireless Sensor Networks for Crop Health Monitoring.

In this study, a crop health monitoring system is developed by using state of the art technologies including wireless sensors and Unmanned Aerial Vehicles (UAVs). Conventionally data is collected from sensor nodes either by fixed base stations or mobile sinks. Mobile sinks are considered a better choice nowadays due to their improved network coverage and energy utilization. Usually, the mobile sink is used in two ways: either it goes for random walk to find the scattered nodes and collect data, or follows a pre-defined path established by the ground network/clusters. Neither of these options is suitable in our scenario due to the factors like dynamic data collection, the strict targeted area required to be scanned, unavailability of a large number of nodes, dynamic path of the UAV, and most importantly, none of these are known in advance. The contribution of this paper is the formation of dynamic runtime clusters of field sensors by considering the above mentioned factors. Furthermore a mechanism (Bayesian classifier) is defined to select best node as cluster head. The proposed system is validated through simulation results, lab and infield experiments using concept devices. The obtained results are encouraging, especially in terms of deployment time, energy, efficiency, throughput and ease of use.

Short and medium-term outcomes for general surgery in nonagenarian patients in a district general hospital.

Introduction Surgeons are increasingly performing surgery on older patients. There are currently no tools specifically for risk prediction in this group. The aim of this study was to review general surgical operations carried out on patients aged over 90 years and their outcome, before comparing these with predictors of morbidity and mortality. Methods A retrospective review was carried out at our district general hospital of all general surgery patients aged over 90 years who underwent a general surgical operation over a period of 14 years. Information collected included demographics, details of procedures, P-POSSUM (Portsmouth Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity), complications and outcomes. Results A total of 119 procedures were carried out, 72 involving entry into the peritoneal cavity. Overall, 14 patients (12%) died within 30 days and 34 (29%) died within one year. Postoperative complications included infection (56%), renal failure (24%), need for transfusion (17%) and readmission within 30 days (11%). Logistical regression analysis showed that the P-POSSUM correlated well with observed mortality and infection was a significant predictor of in-hospital mortality (p=0.003). Conclusions The P-POSSUM correlates significantly with outcome and should be used when planning major elective or emergency surgery in patients over 90 years of age. Infective complications appear to be a significant predictor of postoperative mortality. This study supports operative intervention as an option in this extreme age group but we emphasise the importance of appropriate patient selection and judicious clinical care.

Antiplasmodial Activity of Some Medicinal Plants Used in Sudanese Folk-medicine.

Ten plants indigenous to Sudan and of common use in Sudanese folk-medicine, were examined in vitro for antimalarial activity against schizonts maturation of Plasmodium falciparum, the major human malaria parasite. All plant samples displayed various antiplasmodial activity. Three plant extracts caused 100% inhibition of the parasite growth at concentrations of plant material

Latex agglutination test for the detection of urinary antigens in visceral leishmaniasis.

This paper describes a new latex agglutination test ('KATEX') for the detection of leishmanial antigen in the urine of patients with visceral leishmaniasis. In preliminary laboratory trials, using urine collected from well-defined cases and controls from Brazil, Yemen and Nepal, the test had 100% specificity and a sensitivity between 68 and 100%. When used in a time-course experiment in cotton rats infected with Leishmania donovani, the test became positive 1 week after inoculation and antigen levels in urine declined rapidly after chemotherapy (the test was negative before the end of the course of treatment). Finally, in an integrated study performed in Sudan, KATEX was compared to microscopy and four different serological tests in a group of 73 patients having presented with clinical manifestations suggestive of visceral leishmaniasis. Compared to microscopy, KATEX performed better than any single serological test in predicting positivity and a particularly good result was obtained by combining KATEX and the direct agglutination test (DAT).

Prevalence of hepatitis C virus infection in hemodialysis patients in Sudan.

To estimate the prevalence of positivity of hepatitis C virus (HCV) antibodies in the hemodialysis population in Sudan and the risk factors of this infection in them we studied 46 hemodialysis patients (34 males, 12 females) in the Khartoum Kidney Dialysis Center (KKDC) in December 1994. Also we studied 37 healthy staff members in that unit. The blood of both groups was screened for HCV antibodies using a second generation ELISA test and confirmed by two bead supplemental assays. In the patients group, 16 cases (34.9%) were confirmed seropositive for HCV. There was a history of jaundice in four them. The mean duration on dialysis was 3.28 years in the HCV seropositive group compared with 2.2 years in the HCV seronegative group (P < 0.05). The mean frequency of blood transfusion was 2.68 units of blood in the HCV seropositive group, while it was 3.16 units in the HCV seronegative group which was not significantly different. Only two patients had high liver enzymes in the HCV seropositive groups, while there were seven patients with high liver enzymes in the HCV seronegative group. There were two staff members (5.41%) with positive HCV antibodies, but none had a history of jaundice or elevated liver enzymes. Both staff members were not involved in the direct patients care. We conclude that the prevalence of HCV antibody positivity was high in the hemodialysis population in Sudan. Nosocomial transmission may be the factor of transmission since we found no correlation with the blood transfusions.

Accuracy of mixing oral rehydration solution at home by Egyptian mothers.

PIP: The study was conducted by the Rehydration Unit of Bab El-Sha'reya Hospital, Cairo to determine the impact on the mixing accuracy of oral rehydration solution (ORS) of a group of mothers of infants suffering from acute diarrhea. 1 group received a special 200 ml cup and brief verbal instructions; a control group received neither the cup nor instructions. The mothers were illiterate and of a low socioeconomic class. Results show that the median capacity of home containers used was 160ml/L. The mean ORS sodium concentration (98mmol/L) for the group supplied with the specified container was significantly lower than the ORS sodium concentration (123 mmol/L) of the group that used home containers (p 0.02). All mothers who received the 200 ml cup from the medical unit used it. 96% of mothers in both groups were ready to use ORS in the future. The present study showed that mothers mixing premarked ORS containers along with brief instructions and the 200 ml cups dispensed with the ORS container were more accurate because the standard container was provided. There is no financial obstacle to providing such containers since the cost in Egypt is US$0.1. Such containers could be provided free if Egyptian companies producing pediatric medicines would agree to such containers away as promotional tools.^ieng