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The present study was conducted in the National Sheep Research Station in Elhuda, Sudan where the sheep flocks are kept for scientific research purposes. The aim of the study is to evaluate two systems of sheep productivity namely: the prevailing annual single lamb cropping (sheer-sedentary) and induced three lamb cropping per two years to which feed supplementation is provided (improved - sedentary). Three subtypes: Shugor, Dubasi and Watish in Sudan Desert sheep were used for a three -lamp crops, per two years, in addition to feed supplementation, to represent an improved-sedentary system, (B) against a sheer sedentary (A), that represents an annual single-lamp-crop system. The improved sedentary was associated with reductions in the overall average values of the traits: ewes losses (1.95 vs 3.09%), ewe barrenness (17.30 vs 28.67%) and lambing interval (257.97 vs 353.50 days), whereas it enhanced lambing rate (82.73 vs72.67 %), litter size at weaning measured: as lambs weaned per ewes exposed for breeding (1.01 vs 0.67) and as lambs weaned per ewes that actually lambed (1.12 vs 0.93) improved adjusted lamb weaning weight per ewe at 60 days of lamb age (13.62 vs 10.58 kg), increased lamb survival rate (93.91 vs 75.63%) and eventually promoted productivity index (18.36 vs 5.25kg) of lambs weaned per ewe per year. These overall average values were calculated out of the mean values of the measured traits shown in tables (1 and 2) of the text. Furthermore, the comparison between the three subtype sheep groups for their performance as affected by the improved sedentary against the sheer - sedentary revealed similar trends of response as above, that culminated in the Shugor subtype having the greatest productivity index mean value (20.82 kg) as subsequently compared with that of either the subtype Dubasi (17.56 kg) or the Watish subtype (16.70 kg). It is concluded that these results do encourage the adoption and projection on the improved-sedentary system, specially, under the surroundings of irrigated agriculture land use to provide extra income to the welfare of the farmer. [ABSTRACT FROM AUTHOR]

This study was carried out at the National Sheep Research Station in Elhuda, Sudan to investigate the situation of female sheep conditions while in gestation and to consult some aspects associated to pregnancy parameters and others on live weight were collected, processed and statistically tested in addition to variability consideration. Thus, live weight changes its variability and some relationships for certain reproductive traits in the Shugor and Dubasi subtypes of Sudanese Desert sheep ewes were studied from mating events to the immediate postpartum date. The overall live weight changes during this period resulted in an increase of 22.8 and 27.6% in the live weight of either of these two ewe groups, respectively, but with an overall greater in live weight variability within the Shugor as contrasted with that within their contemporary Dubasi ewe group (11.33vs 8.27%, CV), having periodic mean value which ranges from 10.70 -13.5% CV and 7.2 - 8.5% CV, respectively, for the Shugor and Dubasi ewe groups. The combined contribution of the foetal lamb weights, foetal placenta fluids weights composed 20.0% for the Shugor and 17.9% for the Dubasi of the breeding (mating) live weight of each while the weight of the lamb at birth and that of the associated placenta had mean values of 11.1 ±0.06% and 1.23 ± 0.06, respectively, of the Shugor pre-partum ewe live weight but the corresponding mean proportional values in the Dubasi group were 9.48 ± 0.49% and 1.20 ±0.08 %. The regression of gestation length, post-partum ewe live weight and lamb birth weight had mean values of + 0.37, + 0.71 and 0.002 as related to the breeding (mating) ewe live weight of the Shugor whereas the corresponding regression values in the Dubasi ewes were +0.03, + 0.67 and + 0.03. None of these contrasting parameter values was significantly different in the two subtype groups. Similarly, the regression values of the placenta weight on the lamb birth weight were not significantly different, respecttively, - 0.02 and + 0.032 in the Shugor and Dubasi ewe groups. It is concluded that live weights variations in breeding females should be made manageable to their least possible to allow for more solid data, on the female and its offspring, as this is conductive to performance development. [ABSTRACT FROM AUTHOR]

The unique memory property of thermodynamic wire is only partially understood. It is believed to result from the wire's inherent capability to markedly alter its atomic bonding forces as a function of temperature. This shape recovery phenomenon may be the result of a transition in crystal structure that occurs by deformation and cooling. When the transition is reversed, by heating, the structure reverts to its original form and abrupt property changes occur. The purpose of this study was to determine the transition temperature ranges (TTR) of three commercially available thermodynamic archwires and to determine the rate of recovery of the wires when bent to a uniform shape. A jig was constructed to hold the wires and was suspended in a water bath within a plexiglass box. The temperature of the water bath was gradually increased. A program was written to acquire a single video frame from a running video tape and then allow the operator to graphically overlay the position of each wire specimen. The results indicate that the TTRs for the three commercially available thermodynamic wires are of similar magnitudes (x = 6.7 degrees C, 6.2 degrees C and 6.7 degrees C). The greatest differences were in the standard deviations (1.3 degrees C, 2.2 degrees C and 3.7 degrees C) which may be a function of manufacturing during alloying of the wire and/or its heat treatment.

Various whitening/bleaching systems have been introduced on the market, including an over-the-counter external bleaching material, containing carbamide peroxide. It has been suggested that the process might alter the enamel surface structure in a manner similar to acid etching. Orthodontists are interested in determining whether the process will alter the adhesive characteristics of orthodontic bonding systems. The results of this study indicate that the use of 10% carbamide peroxide did not result in significant changes in the shear debonding strength of orthodontic brackets.