67 research outputs found
Modification of cellulose ether with organic carbonate for enhanced thermal and rheological properties: Characterization and analysis
Reduction in viscosity at higher temperatures is the main limitation of utilizing cellulose ethers in high thermal reservoir conditions for petroleum industry applications. In this study, cellulose ether (hydroxyethyl methyl cellulose (HEMC)) is modified using organic carbonates, i.e., propylene carbonate (PC) and diethyl carbonate (DEC), to overcome the limitation of reduced viscosity at high temperatures. The polymer composites were characterized through various analytical techniques, including Fourier-transform infrared (FTIR), H-NMR, X-ray diffraction (XRD), scanning electron microscope (SEM), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), -potential measurement, molecular weight determination, and rheology measurements. The experimental results of structural and morphological characterization confirm the modification and formation of a new organic carbonate-based cellulose ether. The thermal analysis revealed that the modified composites have greater stability, as the modified samples demonstrated higher vaporization and decomposition temperatures. -potential measurement indicates higher stability of DEC- and PC-modified composites. The relative viscometry measurement revealed that the modification increased the molecular weight of PC- and DEC-containing polymers, up to 93,000 and 99,000 g/moL, respectively. Moreover, the modified composites exhibited higher levels of stability, shear strength and thermal resistance as confirmed by viscosity measurement through rheology determination. The observed increase in viscosity is likely due to the enhanced inter- and intramolecular interaction and higher molecular weight of modified composites. The organic carbonate performed as a transesterification agent that improves the overall properties of cellulose ether (HEMC) at elevated temperatures as concluded from this study. The modification approach in this study will open the doors to new applications and will be beneficial for substantial development in the petroleum industry
Utility of participatory rural appraisal for health needs assessment and planning.
BACKGROUND:
While poverty and lack of life opportunities are root causes of a high burden of disease and infant and maternal mortality, inadequate health care contributes heavily. Often those who are left without care are those who need it most. Existing health services are managed without taking into account acceptance and need perspectives. This further reduces the effectiveness of and equity in health care. In order to guide the planning of reproductive health services by a national NGO, health needs were assessed in a district in Sindh using a combination of participatory rural appraisal (PRA) and qualitative and quantitative research methods. PRA is considered as a better framework to assess, analyse and develop programs with communities. OBJECTIVE:
The objective of PRA was to initiate community involvement and to understand the needs of health care from a community perspective. METHODOLOGY:
PRA was conducted with groups of men and women from three rural areas in a district of Sindh, Pakistan using a life cycle framework. The community members identified various stages of their life with the associated health issues. RESULTS:
This research was empowering to community members as it facilitated community involvement. The respondents took charge of the process of identification of health needs at PRA sessions. PRA helped identify health problems considered prevalent and important by the community. More importantly, it helped potential service providers and the community to initiate community involvement in planning. CONCLUSION:
PRA is not only an effective tool for assessment and analysis of health issues but also a vehicle to promote community involvement. Additionally, participatory methods contribute to understand the context of quantitative data generated for planning purposes
Performance and Emission Analysis of a Diesel Engine Using Linseed Biodiesel Blends
The core object of this study is to examine the suitability of linseeds for biodiesel production. The performance of an engine at different proportions of linseed blends with petro-diesel and the amount of emissions rate were investigated. Initially, linseed biodiesel was produced through transesterification process, and then it was mixed with petro-diesel fuel (D100) blends at volumetric ratios of 10% (LB10), 20% (LB20), and 30% (LB30). The properties of linseed biodiesel and its blends were investigated and compared with petro-diesel properties with reference to ASTM standards. It has been observed that the fuel properties of produced biodiesel are within ASTM permissible limits. The specific fuel consumption (SFC) of LB10 blend has been found lesser compared to LB20 and LB30. SFC of D100 is slightly less than that of all the blends. The brake thermal efficiency (BTE) of LB30 is greater than that of pure diesel D100 at maximum load and greater than that of LB10 and LB20. The heat dissipation rate in all linseed blends is found to have been less than that of D100. Carbon monoxide, carbon dioxide and NOx emissions of linseed blends are mostly lower in comparison with D100’s. Among all blends, LB10 was found more suitable alternative fuel for diesel engines and can be blended with petro diesel without engine modifications. It can be concluded that cultivation and production of linseed in Pakistan is very promising, therefore, it is recommended that proper exploitation and use of linseed for energy production may be encouraged through pertinent agencies of Pakistan
Bladder Sparing Approaches for Muscle-Invasive Bladder Cancers.
OPINION STATEMENT: Organ preservation has been increasingly utilised in the management of muscle-invasive bladder cancer. Multiple bladder preservation options exist, although the approach of maximal TURBT performed along with chemoradiation is the most favoured. Phase III trials have shown superiority of chemoradiotherapy compared to radiotherapy alone. Concurrent chemoradiotherapy gives local control outcomes comparable to those of radical surgery, but seemingly more superior when considering quality of life. Bladder-preserving techniques represent an alternative for patients who are unfit for cystectomy or decline major surgical intervention; however, these patients will need lifelong rigorous surveillance. It is important to emphasise to the patients opting for organ preservation the need for lifelong bladder surveillance as risk of recurrence remains even years after radical chemoradiotherapy treatment. No randomised control trials have yet directly compared radical cystectomy with bladder-preserving chemoradiation, leaving the age-old question of superiority of one modality over another unanswered. Radical cystectomy and chemoradiation, however, must be seen as complimentary treatments rather than competing treatments. Meticulous patient selection is vital in treatment modality selection with the success of recent trials within the field of bladder preservation only being possible through this application of meticulous selection criteria compared to previous decades. A multidisciplinary approach with radiation oncologists, medical oncologists, and urologists is needed to closely monitor patients who undergo bladder preservation in order to optimise outcomes
Is radiation-induced ovarian ablation in breast cancer an obsolete procedure? Results of a meta-analysis
Mushabbab Al Asiri,1,* Mutahir A Tunio,1,* Reham Abdulmoniem,2,*1Radiation Oncology, Comprehensive Cancer Center, King Fahad Medical City, Riyadh, Saudi Arabia; 2Radiation Oncology, National Cancer Institute, Cairo, Egypt *These authors contributed equally to this work Background: A meta-analysis was conducted to assess the impact of radiation-induced ovarian ablation (RT-OA) on amenorrhea cessation rates, progression-free survival, and overall survival in pre/perimenopausal women with breast cancer. Materials and methods: The Medline, CANCERLIT, and Cochrane Library databases and search engines were searched to identify randomized controlled studies comparing RT-OA with control for early or metastatic breast cancer. Further, radiotherapy doses, techniques, and associated side effects were evaluated. Results: Six controlled trials with a total patient population of 3,317 were identified. Pooled results from these trials showed significant amenorrhea rates (P<0.00001) and increase in progression-free survival in patients treated with RT-OA (P<0.00001). However, there was no difference in overall survival (P=0.37). The majority of patients were treated with larger field sizes with parallel-opposed anteroposterior and posteroanterior pelvic fields. RT-OA was generally well tolerated. Radiotherapy doses of 1,500 cGy in five fractions, 1,500 cGy in four fractions, 1,600 cGy in four fractions, and 2,000 cGy in ten fractions were associated with excellent amenorrhea rates. The resultant funnel plot showed no publication bias (Egger test P=0.16). Conclusion: RT-OA is cost-effective and can safely be used in pre/perimenopausal women with metastatic breast cancer, or if luteinizing hormone-releasing hormone analogs are contraindicated, or in patients in whom fertility preservation is not an issue. Radiation dose of 1,500 cGy in five fractions, 1,500 cGy in four fractions, 1,600 cGy in four fractions, and 2,000 cGy in ten fractions showed more efficacies. However, further studies incorporating three-dimensional conformal radiotherapy and intensity-modulated radiotherapy are warranted. Keywords: radiation-induced ovarian ablation, pre/perimenopausal, breast cancer, meta-analysi
IMPROVEMENT OF CONCEPTION RATE IN CROSSBRED CATTLE BY USING GnRH ANALOGUE THERAPY
This study was carried out to evaluate the effect of Dalmarelin (Lecirelin acetate, GnRH analogue) administration at the time of artificial insemination (AI) on conception rate in repeat breeding crossbred cows. A total of 64 cows maintained at the Military Farm Okara, Pakistan were included in the study. The experimental cows were divided into two groups A and B, with 32 cows in each group. Cows of group A received no treatment at the time of AI and served as untreated control, while 32 cows of group B received Dalmarelin therapy at the time of AI. The cows were examined for pregnancy 60 days post insemination per rectum. A total of 12 animals out of 32 were pregnant with a conception rate of 37.5% in control group and in treatment group 22 animals out of 32 were pregnant, having conception rate of 68.75% (P<0.05). The study revealed that use of GnRH analogue therapy improved the conception rate in repeat breeding crossbred cows when it was administered at the time of AI
Is extended-field concurrent chemoradiation an option for radiologic negative paraaortic lymph node, locally advanced cervical cancer?
Mushabbab Al Asiri,1 Mutahir A Tunio,1 Reham Mohamed,2 Yasser Bayoumi,2 Abdulrehman Alhadab,1 Rasha M Saleh,3 Muhannad Saud AlArifi,1 Abdelaziz Alobaid4 1Radiation Oncology, Comprehensive Cancer Center, King Fahad Medical City, Riyadh, Saudi Arabia; 2Radiation Oncology, National Cancer Institute, Cairo University, Cairo, Egypt; 3Medical Oncology, Comprehensive Cancer Center, King Fahad Medical City, Riyadh, Saudi Arabia; 4Women's Specialized Hospital, King Fahad Medical City, Riyadh, Saudi ArabiaBackground: The aim was to evaluate whether extended-field concurrent chemoradiation (EF-CCRT) leads to results better than those obtained by standard whole-pelvis concurrent chemoradiation (WP-CCRT) in locally advanced cervical cancer with radiologic negative paraaortic lymph nodes (PALNs).Patients and methods: A total of 102 patients with histopathologically proven squamous cell carcinoma, adenocarcinoma, or adenosquamous cell carcinoma, and radiologic negative PALN locally advanced cervical cancer, stage IIB-IVA, were accrued between July 2007 and April 2008 and were randomly assigned to WP-CCRT (50 patients) or EF-CCRT (52 patients), followed by high-dose rate brachytherapy. Data regarding the safety profile, response rates, and occurrence of local, PALN, or distant failure were recorded.Results: During a median follow-up time of 60 months (18–66), 74/102 patients completed the treatment protocol and were analyzed. Overall PALN, distant-metastasis control, disease-free survival, and overall survival rates were 97.1%, 86.9%, 80.3%, and 72.4% in EF-CCRT respectively in comparison with WP-CCRT (82.1%,74.7%, 69.1%, and 60.4%), with P-values of 0.02, 0.03, 0.03 and 0.04 respectively. No difference in acute toxicity profile was seen between the groups, and late toxicities were mild and minimal.Conclusion: Prophylactic EF-CCRT can be a reasonable option in patients with locally advanced cervical cancer with radiologic positive pelvic lymph nodes and radiologic negative PALN.Keywords: prophylactic extended field radiation therapy, concurrent chemotherap
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