Covering materials incorporating radiation-preventing techniques to meet greenhouse cooling challenges in arid regions: a review.

Cooling greenhouses is essential to provide a suitable environment for plant growth in arid regions characterized by brackish water resources. However, using conventional cooling methods are facing many challenges. Filtering out near infra-red radiation (NIR) at the greenhouse cover can significantly reduce the heating load and can solve the overheating problem of the greenhouse air. This paper is to review (i) the problems of using conventional cooling methods and (ii) the advantages of greenhouse covers that incorporate NIR reflectors. This survey focuses on how the cover type affects the transmittance of photosynthetically active radiation (PAR), the reflectance or absorptance of NIR and the greenhouse air temperature. NIR-reflecting plastic films seem to be the most suitable, low cost and simple cover for greenhouses under arid conditions. Therefore, this review discusses how various additives should be incorporated in plastic film to increase its mechanical properties, durability and ability to stand up to extremely harsh weather. Presently, NIR-reflecting covers are able to reduce greenhouse air temperature by no more than 5 °C. This reduction is not enough in regions where the ambient temperature may exceed 45 °C in summer. There is a need to develop improved NIR-reflecting plastic film covers.

Role of no scalpel vasectomy in male sterilization.

No Scalpel Vasectomy (NSV) is a modern method of delivery, ligation and excision of vas deference without use of a knife. It provides a permanent sterilization option for male. It is a safe, effective method of vasectomy with low complication and greater patient compliance. To evaluate effectiveness and its acceptance of the procedure data were collected on men who accepted NSV between Jan'2008 to Mar'09. Demographic information, motivating factors, educational status and surgical complications were recorded. The cases were done in rural hospitals & Primary health centers as camp procedure. A total of 649 vasectomies performed using NSV method from Jan'08 to Mar'09. The mean age of the acceptors was 35 years with 4 numbers of children on average. Complications included bleeding during surgery in 4 cases (0.6%), haematoma in one case (0.2%), and superficial wound infection occurred in two cases (0.3%) and scrotal pain in 4 cases (0.6%). NSV is an effective, minimal access method of vas delivery, ligation and excision. It provides safe and effective contraceptive option to male population with minimal complications. Doctors, health workers along with the simplicity of procedure and early return to work are great motivating factors. It is easily performed as camp procedure in a simple medical setup. Doctors can be effectively trained hands on during the camp procedure.

Chemical modification of rubber wood with styrene in combination with a crosslinker: effect on dimensional stability and strength property.

Chemical modification of rubber wood (Hevea Brasiliensis) was carried out by impregnating the wood with styrene and in combination with a crosslinker Glycidyl Methacrylate (GMA). Polymerization was carried out by catalyst heat treatment. The dimensional stability in terms of % volumetric swelling and anti-shrink efficiency was determined and found to be improved on treatment. Water absorption was also found to be decreased considerably for treated wood samples. Mechanical strength of the treated samples in terms of modulus of rupture and modulus of elasticity were also found to be improved. The wood polymer interaction was confirmed by FT-IR spectroscopy. Biodegradability of the wood/polymer composites was determined and found to be improved on treatment with styrene/styrene-GMA.