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In this novel research, S-scheme Ag2CrO4/g-C3N4 heterojunctions were generated by sonochemical hybridization of different compositions of Ag2CrO4 nanoparticles [EVB = +2.21 eV] and g-C3N4 sheets [ECB = -1.3 eV] for destructing RhB dye under artificial solar radiation. The as-synthesized nanocomposites were subjected to X-ray diffraction [XRD], diffuse reflectance spectrum [DRS], X-ray photoelectron spectroscopy [XPS], N2-adsorption-desorption isotherm, photoluminescence [PL] and high resolution transmission electron microscope [HRTEM] analysis to explore the interfacial interactions between g-C3N4 sheets and Ag2CrO4 nanoparticles. Spherical Ag2CrO4 nanoparticles deposited homogeneously on the wrinkles points of g-C3N4 sheets at nearly equidistant from each other facilitating the uniform absorption of solar radiations. The absorbability of solar radiations was enhanced by introducing 20 wt % Ag2CrO4 on g-C3N4 sheets. The surface area of g-C3N4 sheets was reduced from 37.5 to 16.4 m2/g and PL signal intensity diminished by 80 % implying the successful interfacial interaction between Ag2CrO4 nanoparticles and g-C3N4 sheets. The photocatalytic performance of heterojunctions containing 20 % Ag2CrO4 and 80 % g-C3N4 destructed 96 % of RhB dye compared with 60 and 33 % removal on the surface of pristine g-C3N4 sheets and Ag2CrO4, respectively. Benzoquinone and ammonium oxalate are strongly scavenged the dye decomposition revealing the strong influence of valence band holes of Ag2CrO4 and superoxide radicals in destructing RhB dye under solar radiations. S-scheme charge transportation mechanism was suggested rather than type II heterojunction on the light of scavenger trapping experiments results and PL spectrum of terephthalic acid. Overall, this research work illustrated the manipulation of novel S-scheme heterojunction with efficient redox power for destructing various organic pollutants persisted in water resources.

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A total number of 65 specimens of a provisional crown and bridge (PMMA) poly methyl methacrylate (acrylic resin) was utilized in the present study. Sixty specimens were reinforced either by silane-treated or un-silane-treated poly-aramide fibres. The specimens were classified according to the length and the fiber orientations. It was found that, the silanated longitudinally fibered specimens offered the greatest transverse strength (87.2 Mn/m2). On the other hand, the transversely fibered specimens demonstrated the lowest value (44.4 Mn/m2). Moreover, the 6 mm long randomly oriented silanated fibered specimens possessed a higher transverse strength values (73.6 Mn/m2) compared with 3 mm long and the combination 6 mm + 3 mm long silanated fibered specimens (55.2 Mn/m2 and 62 Mn/m2) respectively. It was demonstrated also that, the inclusion of the un-silanated fibers reduced the transverse strength values of the resin specimens dramatically.

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PURPOSE: Radiobiological modeling was used to explore optimum combination strategies for treatment of disseminated malignancies of differing radiosensitivity and differing patterns of metastatic spread. The purpose of the study was to derive robust conclusions about the design of combination strategies that incorporate a targeting component. Preliminary clinical experience of a neuroblastoma treatment strategy, which is based upon general principles obtained from modelling, is briefly described. METHODS AND MATERIALS: The radiobiological analysis was based on an extended (dose-rate dependent) formulation of the linear quadratic model. Radiation dose and dose rate for targeted irradiation of tumors of differing size was in part based on microdosimetric considerations. The analysis was applied to several tumor types with postulated differences in the pattern of metastatic spread, represented by the steepness of the slope of the relationship between numbers of tumors present and tumor diameter. The clinical pilot study entailed the treatment of five children with advanced neuroblastoma using a combination of 131I metaiodobenzylguanidine (mIBG) and total body irradiation followed by bone marrow rescue. RESULTS: The theoretical analysis shows that both intrinsic radiosensitivity and pattern of metastatic spread can influence the composition of the ideal optimum combination strategy. High intrinsic radiosensitivity generally favors a high proportion of targeting component in the combination treatment, while a strong tendency to micrometastatic spread favors a major contribution by total body irradiation. The neuroblastoma patients were treated using a combination regimen with an initially low targeting component (2 Gy whole body dose from targeting component plus 12 Gy from total body irradiation). The treatment was tolerable and resulted in remissions in excess of 9 months in each of these advanced neuroblastoma patients. CONCLUSIONS: Radiobiological analysis, which incorporates simple models of metastatic spread, emphasizes the importance of the total body irradiation component in a targeting/total body irradiation combination strategy. However, the analysis favors a larger targeting component than is used in clinical practice at present. A cautious escalation of the 131I mIBG component in the combination treatment of advanced neuroblastoma appears justified.

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The pesticides endosulfan and amitraz were fed to 2 groups of Nubian goats (3 goats/group) at 5 mg/kg/d for 36 d to assess their effects on feedlot performance, carcass yield and meat quality. Growth rates, weight gains and feed conversion efficiencies were depressed insignificantly. The endosulfan-dosed group had significantly lower dressing-out percentage and both groups had significant depletions of omental and mesenteric fats. Significant reductions were also seen on body and cavity fats, the latter being severely reduced suggesting more mobilization of cavity fat than body fat. The fat-free body was homogenous with variations in the muscle/bone ratio reflected on carcass cuts. Meat quality was unaffected. Fat was the only chemical component of endosulfan-dosed total lean significantly reduced. In all parameters the effects of endosulfan were more pronounced than those of amitraz.

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PURPOSE: A model is presented for calculating combinations of targeted 131I and total body irradiation, followed by bone marrow rescue, in the treatment of tumors of different radiosensitivity. The model is used to evaluate the role of the total body irradiation component in the optimal combination regime as a function of the radiosensitivity of the tumor cells. METHODS AND MATERIALS: A microdosimetric model was used to calculate absorbed dose in small tumors and micrometastases when uniformly targeted by the radionuclide 131I. Cell kill was calculated from absorbed dose using an extended version of the linear quadratic model. The addition of varying total doses of total body irradiation, assuming 2 Gy fractions, was also calculated using the linear quadratic model. The net cell kill from combined modality (targeted 131I and total body irradiation) was computed for varying proportions of the two components, for a range of tumor sizes, restricting the total radiation dose to within tolerance for a full-course TBI regime (approximately 14 Gy total) in all cases. The calculations were repeated for a range of presumed tumor uptakes of the targeting agent and for a range of tumor radiosensitivities, typical of those reported for tumor cells of differing type in culture. Optimal regimes were identified as those predicted to yield a high probable tumor cure rate (evaluated using a Poisson statistical model) for all tumor sizes. RESULTS: The analysis supports earlier model studies which predicted that systemic combination treatment with targeted 131I and total body irradiation would be superior to either component used alone. The intrinsic tumor radiosensitivity is found to be a factor which influences the optimal combination of the 131I and external beam total body irradiation components. The total body irradiation component is greater in optimal regimes treating radio-resistant than radiosensitive tumors. However, an obligatory total body irradiation component is also predicted for more radiosensitive tumors; the analysis suggests that the total body irradiation component should in no circumstances be less than 2 x 2 Gy, whilst practical arguments exist in favor of higher doses. CONCLUSION: Total body irradiation is an obligatory component for effective systemic treatment of disseminated malignant tumors to which 131I can be selectively targeted. Clinical studies applying this strategy to the treatment of neuroblastoma by 131I targeted by meta-iodo-benguanidine (mIBG), total body irradiation and bone marrow rescue are now in progress.

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Molasses at 10, 30 or 50% of the diet for 12 w was not toxic to goats and could be used as an inexpensive substitute for sorghum grain. No animals showed signs or lesions of illness attributable to feeding molasses. There were no differences among treatment groups in any of the following parameters: WBC, RBC, PCV, Hb, MCV, MCHC, GOT, uric acid, urea, cholesterol, and zinc. Serum creatinine, total protein, iron, copper, magnesium and calcium varied between groups but remained within the ranges for normal goats. Feedlot performance indicated that utilization of molasses energy for body weight gain was a function of intake; feeding 50% dietary molasses did not produce economic weight gain.

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Nubian goats were given single or repeated dosages of 5, 2.5 and 0.25 g/kg of dried leaves or stem of C. tomentosa by drench and died or were slaughtered at various times post-dosing. One goat receiving Capparis stem at 2.5 g/kg on every other day basis for 8 days developed signs of toxicosis and recovered following cessation of plant administration. The prominent features of toxicity were inappetence, locomotor disturbances, paresis especially of the hind limbs and recumbency. Lesions comprised perineuronal vacuolation in the gray matter of the spinal cord at the sacral region, centrilobular hepatocellular necrosis, degeneration of the renal proximal convoluted and collecting tubules, serous atrophy of the cardiac fat and renal pelvis and straw-coloured fluid in serious cavities. In Capparis-fed goats, anaemia developed and the results of kidney and liver function tests were correlated with clinical abnormalities and pathologic changes.

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131I is the radionuclide most commonly used in biologically targeted radiotherapy at the present time. Microdosimetric analysis has shown that microtumors whose diameters are less than the beta-particle maximum range absorb radiation energy inefficiently from targeted radionuclides. Micrometastases of diameters < 1 mm are likely to be spared if targeted 131I is used as a single modality. Because of this, combined modality therapy incorporating targeted 131I, external beam total-body irradiation (TBI), and bone marrow rescue has been proposed. In this study, the minimum necessary TBI component is shown to depend on the radiosensitivity of the tumor cells. The analysis shows that the TBI component, to achieve radiocurability, increases directly with tumor radioresistance. For the most radiosensitive tumors, a whole-body TBI treatment dose 2 x 2 Gy is calculated to be obligatory, whereas practical arguments exist in favor of higher doses. For more radioresistant tumors, the analysis implies that a TBI treatment delivery of 5 x 2 Gy is obligatory. In all situations, external beam TBI appears to be an essential factor in providing reasonable probability of cure of disseminated malignant disease. Reasonable prospects of tumor cure by combination strategies incorporating 131I exist for the more radiosensitive tumor types (e.g., neuroblastoma, lymphoma, leukemia, myeloma, seminoma), but more resistant tumors are unlikely to be curable at present. Superior targeting agents, and the possible use of panels of different radionuclides, may be necessary to achieve high cure probabilities for less radiosensitive tumor types.

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