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Use of antibiotics as feed additives has been reduced to avoid the hazard of drug residues, and consequently, the search for alternative natural additives has developed. Thus, the aim was to evaluate the influence of royal jelly (RJ) supplementation on milk composition, blood biochemical and antioxidant parameters of lactating ewes. Thirty-six Ossimi ewes were divided randomly into two groups (18 animals each). For a period of 4 weeks, the control group (CON) was fed a basal diet only, while the other group was fed the basal diet and supplemented with a single bolus of RJ (1000 mg/head). The RJ-supplemented ewes produced significantly higher milk protein, fat and total solids than the CON group. The RJ group had a significantly higher red blood cell count, haemoglobin content, haematocrit value and total leucocyte counts, but lower neutrophil to lymphocyte ratio when compared with the control treatment. The RJ group showed significantly higher concentrations of total antioxidant capacity, superoxide dismutase activity and glutathione in the serum compared with the control treatment. In conclusion, RJ supplements can improve the nutritive value of milk fat and the serum antioxidant activities in lactating ewes.
In this paper, a type of parallel robot with three translational degrees of freedom is studied. Inverse and forward kinematic equations are extracted for position and velocity analyses. The dynamic model is derived by Lagrange’s approach and the principle of virtual work and related computational algorithms implementing inverse and forward dynamics are presented. Furthermore, some numerical simulations are performed using the kinematic and dynamic models in which the results show good agreement with expected qualitative behavior of the mechanism. Comparisons with the results of work-energy and impulse-momentum methods quantitatively verify the validity of the derived equations of motion. Also, a relative computational effectiveness is observed in implementation of virtual work model via the simulations.
This work aims to compare the dosimetric performance of three-dimensional conformal radiotherapy (3D-CRT), a relatively available technique in developing countries, to intensity-modulated radiotherapy (IMRT) in the treatment of different stages of nasopharyngeal carcinoma (NPC).
Materials and Methods
According to the diagnostic stages, 40 NPC patients were divided into two equal groups. Three planning techniques such as 3D-CRT, seven-field IMRT (7F-IMRT) and nine-field IMRT (9F-IMRT) were compared. Dose prescriptions of 70 and 66 Gy were delivered in 35 fractions to gross planning target volume (PTV1) and bilateral retropharyngeal carcinoma (PTV2), respectively.
Stage I dose data for almost all of the three investigated planning techniques obey the international recommendations. The dose delivered to PTV1 and PTV2 for 3D-CRT and 7F-IMRT are statistically similar, whereas 9F-IMRT is significantly better than 3D-CRT. For organs at risk (OARs), the delivered dose is significantly better for 9F-IMRT compared with the other two techniques, whereas 7F-IMRT is significantly better than 3D-CRT.
3D-CRT is an acceptable alternative treatment technique for stage I NPC patients in developing countries suffering from the lack of advanced radiotherapy treatment techniques. 3D-CRT and 7F-IMRT have comparable performance in PTVs, while 9F-IMRT is superior in PTVs and OARs.
Maintenance plays a critical role in reducing operating cost and maximizing reliability of a complex engineering system. This paper proposes a novel maintenance-focused, system-level design framework that attempts to capture the interactions between maintenance strategies and system-level design parameters overlooked in current modeling approaches. The goal of this maintenance-focused approach is to help designers better understand the interconnectedness of system architecture, choice of maintenance strategy, and uncertainties in a design. Application of the proposed design framework is demonstrated through a case example of a power plant condenser system. Results show that using an integrated approach can reveal the many nonobvious interactions between subsystems, and produce system designs that have lower life-cycle cost compared to traditional sequential design approaches.
Background: Coronary artery lesions in Kawasaki disease invasively assessed by coronary angiography. Evaluation of myocardial perfusion by single-photon emission computed tomography may identify the haemodynamic significance of coronary lesions. Objective: To evaluate diagnostic accuracy of dipyridamole stress technetium-99 m tetrofosmin, single-photon emission computed tomography as a possible alternative to invasive coronary angiography for detection and follow-up of myocardial ischaemia in patients with Kawasaki disease, and pre- and post-coronary bypass grafting. Patients and methods: Coronary angiography and single-photon emission computed tomography were performed on 21 patients who were classified into three groups – group I (stenosis), group II (giant aneurysms), and group III (small aneurysms). Of the 21 patients, 16 (groups I and II) patients with myocardial perfusion defects, who underwent coronary bypass grafting, were followed up with single-photon emission computed tomography. Result: In group I, all patients had significant coronary stenosis and 100% of them had perfusion defects in the anterior and septal walls. In group II, all patients had giant aneurysms and 83% of them had inferior and inferolateral perfusion defects. In group III, all patients had small aneurysms and 100% of them had normal perfusion. Pre-coronary bypass grafting myocardial ischaemic defects disappeared in all patients after surgery. Sensitivity, specificity, and accuracy of single-photon emission computed tomography were 94, 100, and 95%, respectively. Conclusion: Technetium-99 m tetrofosmin single-photon emission computed tomography can be applied as an accurate non-invasive diagnostic technique for detecting myocardial perfusion defects with coronary artery lesions, and to show improved or even normalised perfusion of the myocardium in patients after surgical revascularisation.
To compare the outcome among patients with invasive bladder cancer treated with cystectomy alone with outcome among those treated with combined-modality treatment in a randomised phase III trial.
Patients and methods
Patients with histologically confirmed invasive non-metastatic bladder cancer T2-3, N0 and M0 were randomly assigned to two arms: Arm 1: of which all patients underwent radical cystectomy (RC) alone; and Arm 2, of which all patients were subjected to maximal transurethral resection of bladder tumour, followed 2 weeks later by combined chemoradiotherapy. The whole pelvis received 46 Gy in 23 fractions over 4·5 weeks. Chemotherapy was administered concomitantly with radiotherapy with: cisplatin 70 mg/m2 q. 3 weeks and Gemcitabine 300 mg/m2 D 1, 8 and 15 q. 3 weeks for two cycles. Patients who had complete response were shifted to phase II treatment: 20 Gy/10 fractions/2 weeks to the bladder. Patients with residual tumour underwent RC.
Of the 80 patients assigned Arm 2, a visibly completed transurethral resection of the bladder tumour was possible in 48 patients (60%). Phase I of combined chemoradiotherapy (CCRT) was accomplished in 74 patients. Post-induction urologic evaluation revealed no evidence of disease in 62 patients (83·8%) and residual disease in 12 patients (16·2%). Phase II of CCRT was completed in 58 of the 62 patients. The median follow-up for all patients is 27 months (range: 4–49). The 3-year overall survival (OS) for the combined-modality group and for the surgery group were 61 and 63%, respectively (p = 0·425), whereas the disease-specific survival (DSS) for each group was 69 and 73%, respectively (p = 0·714). The 3-year OS with bladder preservation for Arm 2 patients was 50%.
Multivariate analysis for the whole series showed that tumour stage and performance status (PS) were the only factors independently associated with DSS, although PS was the only factor independently associated with OS. In addition, residual disease after transurethral resection of the bladder tumour in Arm 2 patients was independently associated with both DSS and OS.
Acute toxicity was moderate and most of the late toxicities were grade 2 with no grade 4 toxicity and no treatment-related deaths, none required cystectomy for bladder contraction.
This study demonstrates that trimodality bladder-preserving approach represents a valid alternative for suitable patients. The OS and DSS rates of patients treated with trimodality bladder-preserving protocol are comparable to the results reported on patients treated with immediate radical cystectomy.
This study examines the trends and determinants of child marriage among women aged 20–49 in Bangladesh. Data were extracted from the last six nationally representative Demographic and Health Surveys conducted during 1993–2011. Simple cross-tabulation and multivariate binary logistic regression analyses were adopted. According to the survey conducted in 2011, more than 75% of marriages can be categorized as child marriages. This is a decline of 10 percentage points in the prevalence of child marriage compared with the survey conducted in 1993–1994. Despite some improvements in education and other socioeconomic indicators, Bangladeshi society still faces the relentless practice of early marriage. The mean age at first marriage has increased by only 1.4 years over the last one and half decades, from 14.3 years in 1993–1994 to 15.7 years in 2011. Although the situation on risk of child marriage has improved over time, the pace is sluggish. Both the year-of-birth and year-of-marriage cohorts of women suggest that the likelihood of marrying as a child has decreased significantly in recent years. The risk of child marriage was significantly higher when husbands had no formal education or little education, and when the wives were unemployed or unskilled workers. Muslim women living in rural areas have a greater risk of child marriage. Women's education level was the single most significant negative determinant of child marriage. Thus, the variables identified as important determinants of child marriage are: education of women and their husbands, and women's occupation, place of residence and religion. Programmes to help and motivate girls to stay in school will not only reduce early marriage but will also support overall societal development. The rigid enforcement of the legal minimum age at first marriage could be critical in decreasing child marriage.
The goal of this study is to empirically investigate the major hot rolling process
parameters affecting the yield strength, ultimate tensile strength and strain-hardening
exponent of Nb-microalloyed steel sheets. The parameters considered were the roughing,
finishing and coiling temperatures. Three levels for each parameter were used to develop a
model relating the process parameters to mechanical properties. By applying the response
surface methodology, analysis of variance was done to determine the mathematical models
related to each response. The results indicated that decreasing the coiling and finishing
temperatures significantly influenced the mechanical properties. Also, the models
predicted that the maximum yield strength, ultimate tensile strength and strain-hardening
exponent are simultaneously obtained under the following conditions: roughing temperature
= 1097 °C, finishing temperature = 837 °C and coiling temperature = 580 °C. The predicted
values were close to the experimental values, indicating the suitability of the
A nonlinear stability of two superposed semi-infinite Walters B′ viscoelastic dielectric fluids streaming through porous media in the presence of vertical electric fields in absence of surface charges at their interface is investigated in three dimensions. The method of multiple scales is used to obtain a Ginzburg-Landau equation with complex coefficients describing the behavior of the system. The stability of the system is discussed both analytically and numerically in linear and nonlinear cases, and the corresponding stability conditions are obtained. It is found, in the linear case, that the surface tension and medium permeability have stabilizing effects, and the fluid velocities, electric fields and kinematic viscoelastici-ties have destabilizing effects, while the porosity of porous medium and kinematic viscosities have dual role on the stability. In the nonlinear case, it is found that the fluid velocities, kinematic viscosities, kinematic viscoelasticities, surface tension and porosity of porous medium have stabilizing effects; while the electric fields and medium permeability have destabilizing effects.
By conducting a case-control study in two university hospitals, we explored the association between modifiable risk behaviours and diarrhoea. Children aged <5 years attending outpatient clinics for diarrhoea were matched by age and sex with controls. Data were collected on family demographics, socioeconomic indicators, and risk behaviour practices. Two rectal swabs and a stool specimen were collected from cases and controls. Samples were cultured for bacterial pathogens using standard techniques and tested by ELISA to detect rotavirus and Cryptosporidium spp. Four hundred cases and controls were enrolled between 2007 and 2009. The strongest independent risk factors for diarrhoea were: presence of another household member with diarrhoea [matched odds ratio (mOR) 4·9, 95% CI 2·8–8·4] in the week preceding the survey, introduction to a new kind of food (mOR 3, 95% CI 1·7–5·4), and the child being cared for outside home (mOR 2·6, 95% CI 1·3–5·2). While these risk factors are not identifiable, in some age groups more easily modifiable risk factors were identified including: having no soap for handwashing (mOR 6·3, 95% CI 1·2–33·9) for children aged 7–12 months, and pacifier use (mOR 1·9, 95% CI 1·0–3·5) in children aged 0–6 months. In total, the findings of this study suggest that community-based interventions to improve practices related to sanitation and hygiene, handwashing and food could be utilized to reduce the burden of diarrhoea in Egyptian children aged <5 years.
Mathematical formulation for Magnetohydrodynamic (MHD) stability of a streaming cylindrical model penetrated by varying transverse magnetic field is presented. Eigen value relation is derived and discussed analytically. In the current paper, Artificial Neural Network (ANN) model, one of the artificial intelligence techniques, is developed to simulate the stability of streaming jet penetrated by magnetic field. The ANN results presented in the current study showed that ANN technique, with less effort and time, is very efficiently capable of simulating and predicting the effect of magnetic field variation and axial exterior field on the stability of the streaming jet. The influence of magnetic field has a stabilizing effect for all short and long wavelengths. However the streaming is strongly destabilizing.
The present work reports the synthesis of self-organized strontium-doped titania nanotubes arrays as a potential material for photocatalytic water splitting. Electrochemical anodization process was used to grow such material under various electrochemical conditions. The effect of dopant concentration on the morphology and photoelectrochemical properties of the material was investigated. The microstructure, morphology and composition of as-prepared and heat treated nanotubes were characterized by field emission scanning electron microscopy (FESEM), x-ray diffraction (XRD), transmission electron microscopy (TEM) and x-ray photoelectron spectroscopy (XPS). The results showed that increasing the dopant concentration up to its solubility limit results in higher photoelectrochemical activity. A preliminary proof of concept of the photocatalytic activity of the fabricated material was estimated in terms of the use of such material as a photoanode for photoelectrochemical water splitting.
Single-phase KNbO3 was prepared using bimetallic alkoxides. Potassium-niobium ethoxide, KNb(OC2H5)6, and potassium-niobium propoxide, KNb(OC3H7)6, were synthesized and subsequently hydrolyzed using several water concentrations. Potassium-deficient particles were rapidly precipitated when higher water concentrations were used and this resulted in the formation of a multiphase material after calcination. In contrast, single-phase KNbO3 powders could be prepared by two methods: (1) hydrolysis of KNb(OC3H7)6/propanol solutions using 1 mole water (per mole of propoxide) added as a water/propanol solution and (2) hydrolysis of KNb(OC2H5)6,/ethanol solutions using 1 mole of water (per mole of ethoxide) added as a water/methanol solution. The latter method was also used to form thin films of KNbO3.