101 research outputs found
Heartwood Extractives of a Western Larch Tree (Larix Occidentalis Nutt.)
Heartwood meal of a western larch (Larix occidentalis Nutt.) was successively extracted with solvents of increasing polarity. The total extractable material collected was 15%. Compounds in each solvent fraction were separated by column chromatography followed by preparative-layer chromatography. Some isolates were characterized by comparison with standards, IR, UV, and NMR spectra, and various chromatographic parameters.Compounds previously unreported found in western larch heartwood were: four resin acids (0.2% total yield), sandaracopimaric, isopimaric, abietic and dehydroabietic, together with larixol and larixyl acetate from the petroleum ether extract; pinocembrin (5,7-dihydroxy-flavanone) from the benzene extract (0.003% yield); isolariciresinol from the ethanol extract; and free L-arabinose and secoisolariciresinol from the water extract
Exergetic analysis of breakfast cereal production in Nigeria
This work comprehensively studied energy and exergy analyses of breakfast cereal production in Nigeria. The process analysis method of energy accounting wa s used to evaluate the energy requirement for each of the five defined unit operations. The total energy used in the operation is 1,287.94 MJ. The types of energy used in breakfast cereal production were electrical, thermal and manual and the respective pe rcentages are 48.87%, 50.53% and 0.60%. It was estimated that an average energy intensity of 11.27 MJ/kg was required for the production of breakfast cereals. The most energy intensive operation was identified as the mixing operation followed by milling with energy intensities of 665.10 MJ/kg and 383.04 MJ/kg, respectively. The exergy analysis revealed that the roller dryer was responsible for most of the inefficiency (over 65.94%) followed by the wet mixer (27.40%). Suggestions for energy saving which will help in the reducing the high expenditure on energy and thus improve the profit margin were provided. Keywords : Energy, Exergy, Efficiency Breakfast Cerea
Relationship between rickets and incomplete distal renal tubular acidosis in children
<p>Abstract</p> <p>Background</p> <p>In the Sub Saharan Africa Rickets has now been established to be due primarily to calcium deficiency and sometimes in combination with vitamin D deficiency. The main thrust of management is calcium supplementation with or without vitamin D. An observation was made that some children with nutritional rickets do not respond to this management modality. The recently reported high prevalence of Incomplete Distal Renal Tubular Acidosis (idRTA) in adults with osteoporosis as brought to fore the possibility of this being a possible cause of calcium wastage and therefore the poor response in these group of children with rickets.</p> <p>Aim</p> <p>To determine the prevalence of idRTA amongst a cohort of subjects with rickets</p> <p>To show a relationship between rickets and incomplete distal renal acidosis</p> <p>To determine the response of children with rickets and idRTA to addition of Shohl's solution to therapy</p> <p>Methodology</p> <p>Two separate cohorts of children with rickets performed the ammonium chloride loading test to detect those with incomplete renal tubular acidosis. Following identification for idRTA, Shohl's solution was added to therapy of calcium and vitamin D supplementation and their response compared to those without idRTA on calcium and vitamin D supplementation solely.</p> <p>Results</p> <p>50 children with rickets aged from two to six years of age and composed of 29 females and 21males were investigated. Incomplete renal tubular acidosis was found in 38% of them. Prevalence of idRTA was highest amongst those aged 3-6 years of age. Those with idRTA had worse limb deformities, biochemical and radiological parameters than those who hadn't. Rate of response on those with idRTA treated with Shohl's solution was at par with those without idRTA.</p> <p>Conclusion</p> <p>Incomplete idRTA exist amongst children with rickets and should be looked out for in severe rickets and older children. Treatment of idRTA will lead to optimal response and healing of rickets.</p
Numerical and Analytical Modeling of Solar for Chimney Combined Ventilation and Power in Buildings
Analytical and numerical studies were carried out to investigate the performance of the combined solar chimney for power generating system and ventilation based on a developed mathematical model. Numerical solution of the problem was based on the continuity, momentum and energy equations for turbulent, steady-flow using k-ε model and the finite volume method using ANSYS Fluent CFD package. The analysis domain was a 2-D room of 4 x 4 m2 with solar chimney of various dimension attached. The results obtained revealed that Chimney Height (CH), Collector Width (CW), Solar Heat Flux (SHF) and ambient wind speed were found to be the most important factors in the design of the SC. Results showed that the room mass flow rate increased from 1 kg/s with no wind effect to about 30 kg/s with induced wind of 1 m/s. The mass flow rate increased from about 6 to 9 kg/s at CH of 5 and 8 m respectively for no wind condition and SHF of 400 W/m2. Power outputs were obtained for the average velocity of the chimney, collector area and chimney height. It was observed from results obtained from both the numerical and analytical analysis that power outputs of the power generating systems increases with increase in heat energy in the collector space area which is a function of the global solar radiation intensity, the collector area, and the chimney height. The power outputs results showed that with SHF of 400 W/m2 for CH of 5 and 9 m were 33 and 85 W/m2 respectively. The respective power output for SHF of 200 and 1,000 W/m2 were 25 and 47 W/m2. Furthermore, the optimum values of CH, CW and SHF were 5 m, 1 m and 417 W/m2 respectively under no wind condition with room temperature of 300 K and chimney velocity 0.12 m/s. It was also observed that with the increase in the mass flow rate in the chimney, the ventilation requirements were adequately met
Modulation of PON2 and Proinflammatory Cytokine Genes in Rat Tissue Exposed to Combined oral Contraceptive Ethinylestradiol and Levonorgestrel
Paraoxonase (PON2) was identified as a genetic risk factor for cardiovascular disease (CVD) and usage of oral contraceptive (OC) is associated with increased cervical cancer and cardiovascular risk. PON2 protect against atherosclerosis development at the cellular level and this phenomenon could be related to their antioxidative properties. Therefore, the aim of the present study was to investigate the effect of OC on the expression of PON2, pro-inflammatory cytokines interleukin one alpha (IL1α) and tumor necrosis factor alpha (TNFα) in the liver, kidney and brain of rats. Different dosage groups of eight female rats were treated with oral contraceptive (0.15mg levonorgestrel 0.03mg ethinylestradiol(A); 0.3mg levonorgestrel 0.06 mg ethinylestradiol (B) and 0.075 mg levonorgestrel 0.015 mg ethinylestradiol (C))/kg body-weight(bw)). Two groups of eight rats were included in the study for a control group (D) and ≤0.1% DMSO (drug vehicle) group (E), which were not subject to drug administration for 21days. The levels of expression of the gene were assessed using quantitative reverse polymerase chain reaction technique. Combined oral contraceptive treatment produced a significant increase(p<0.001) in the level expression of renal IL1α and TNFα in all the groups compared to control in a dose-dependent manner but has no significant effect on PON2.
Meanwhile, OC resulted in significantly (p<0.0001) reduced level of expression of hepatic IL1α with no significant effect on hepatic PON2 and TNFα level. In the brain, OC resulted in significantly (p<0.0001) reduced level of expression of TNFα in all dose groups and IL1α level at 0.015mg/bw. Although OC treatment did increase the expression of brain PON2 significantly (p<0.05) at the lowest dose. Therefore, pharmacological modulation of the expression of genes could constitute a useful approach for preventing atherosclerosi
Developing a digital intervention for cancer survivors: an evidence-, theory- and person-based approach
This paper illustrates a rigorous approach to developing digital interventions using an evidence-, theory- and person-based approach. Intervention planning included a rapid scoping review which identified cancer survivors’ needs, including barriers and facilitators to intervention success. Review evidence (N=49 papers) informed the intervention’s Guiding Principles, theory-based behavioural analysis and logic model. The intervention was optimised based on feedback on a prototype intervention through interviews (N=96) with cancer survivors and focus groups with NHS staff and cancer charity workers (N=31). Interviews with cancer survivors highlighted barriers to engagement, such as concerns about physical activity worsening fatigue. Focus groups highlighted concerns about support appointment length and how to support distressed participants. Feedback informed intervention modifications, to maximise acceptability, feasibility and likelihood of behaviour change. Our systematic method for understanding user views enabled us to anticipate and address important barriers to engagement. This methodology may be useful to others developing digital interventions
Utilisation of an operative difficulty grading scale for laparoscopic cholecystectomy
Background
A reliable system for grading operative difficulty of laparoscopic cholecystectomy would standardise description of findings and reporting of outcomes. The aim of this study was to validate a difficulty grading system (Nassar scale), testing its applicability and consistency in two large prospective datasets.
Methods
Patient and disease-related variables and 30-day outcomes were identified in two prospective cholecystectomy databases: the multi-centre prospective cohort of 8820 patients from the recent CholeS Study and the single-surgeon series containing 4089 patients. Operative data and patient outcomes were correlated with Nassar operative difficultly scale, using Kendall’s tau for dichotomous variables, or Jonckheere–Terpstra tests for continuous variables. A ROC curve analysis was performed, to quantify the predictive accuracy of the scale for each outcome, with continuous outcomes dichotomised, prior to analysis.
Results
A higher operative difficulty grade was consistently associated with worse outcomes for the patients in both the reference and CholeS cohorts. The median length of stay increased from 0 to 4 days, and the 30-day complication rate from 7.6 to 24.4% as the difficulty grade increased from 1 to 4/5 (both p < 0.001). In the CholeS cohort, a higher difficulty grade was found to be most strongly associated with conversion to open and 30-day mortality (AUROC = 0.903, 0.822, respectively). On multivariable analysis, the Nassar operative difficultly scale was found to be a significant independent predictor of operative duration, conversion to open surgery, 30-day complications and 30-day reintervention (all p < 0.001).
Conclusion
We have shown that an operative difficulty scale can standardise the description of operative findings by multiple grades of surgeons to facilitate audit, training assessment and research. It provides a tool for reporting operative findings, disease severity and technical difficulty and can be utilised in future research to reliably compare outcomes according to case mix and intra-operative difficulty
The impact of muscle relaxation techniques on the quality of life of cancer patients, as measured by the FACT-G questionnaire
Introduction Patients with cancer frequently suffer from emotional distress, characterized by psychological symptoms such as anxiety or depression. The presence of psychological symptoms combined with the complex nature of oncology processes can negatively impact patients' quality of life. We aimed to determine the impact of a relaxation protocol on improving quality of life in a sample of oncological patients treated in the Spanish National Public Health System. Materials and methods We conducted a multicenter interventional study without a control group. In total, 272 patients with different oncologic pathologies and showing symptoms of anxiety were recruited from 10 Spanish public hospitals. The intervention comprised abbreviated progressive muscle relaxation training, according to Bernstein and Borkovec. This was followed by weekly telephone calls to each patient over a 1-month period. We collected sociodemographic variables related to the disease process, including information about mental health and the intervention. Patients' quality of life was assessed using the Functional Assessment of Cancer Therapy-General (FACT-G) questionnaire. Bivariate and univariate analyses were performed, along with an analysis of multiple correspondences to identify subgroups of patients with similar variations on the FACT-G. Results Patients showed statistically significant improvements on the FACT-G overall score (W = 16806; p<0.001), with an initial mean score of 55.33±10.42 and a final mean score of 64.49±7.70. We also found significant improvements for all subscales: emotional wellbeing (W = 13118; p<0.001), functional wellbeing (W = 16155.5; p<0.001), physical wellbeing (W = 8885.5; p<0.001), and social and family context (W = ?1840; p = 0.037). Conclusions Patients with cancer who learned and practiced abbreviated progressive muscle relaxation experienced improvement in their perceived quality of life as measured by the FACT-G. Our findings support a previous assumption that complementary techniques (including relaxation techniques) are effective in improving the quality of life of patients with cancer
The Role of Medical Interpretation on Breast and Cervical Cancer Screening Among Asian American and Pacific Islander Women
We examined whether the impact of medical interpretation services was associated with the receipt of a mammogram, clinical breast exam, and Pap smear. We conducted a large cross-sectional study involving four Asian American and Pacific Islander (AAPI) communities with high proportions of individuals with limited English proficiency (LEP). Participants were recruited from community clinics, churches and temples, supermarkets, and other community gathering sites in Northern and Southern California. Among those that responded, 98% completed the survey rendering a total of 1,708 AAPI women. In a series of multivariate logistic regression models, it was found that women who typically used a medical interpreter had a greater odds of having received a mammogram (odds ratio [OR] = 1.85; 95% confidence interval [CI] = 1.21, 2.83), clinical breast exam (OR = 3.03; 95% CI = 1.82, 5.03), and a Pap smear (OR = 2.34; 95% CI = 1.38, 3.97) than those who did not usually use an interpreter. The study provides support for increasing language access in healthcare settings. In particular, medical interpreters may help increase the utilization of breast and cervical cancer screening among LEP AAPI women
The development and validation of a scoring tool to predict the operative duration of elective laparoscopic cholecystectomy
Background: The ability to accurately predict operative duration has the potential to optimise theatre efficiency and utilisation, thus reducing costs and increasing staff and patient satisfaction. With laparoscopic cholecystectomy being one of the most commonly performed procedures worldwide, a tool to predict operative duration could be extremely beneficial to healthcare organisations.
Methods: Data collected from the CholeS study on patients undergoing cholecystectomy in UK and Irish hospitals between 04/2014 and 05/2014 were used to study operative duration. A multivariable binary logistic regression model was produced in order to identify significant independent predictors of long (> 90 min) operations. The resulting model was converted to a risk score, which was subsequently validated on second cohort of patients using ROC curves.
Results: After exclusions, data were available for 7227 patients in the derivation (CholeS) cohort. The median operative duration was 60 min (interquartile range 45–85), with 17.7% of operations lasting longer than 90 min. Ten factors were found to be significant independent predictors of operative durations > 90 min, including ASA, age, previous surgical admissions, BMI, gallbladder wall thickness and CBD diameter. A risk score was then produced from these factors, and applied to a cohort of 2405 patients from a tertiary centre for external validation. This returned an area under the ROC curve of 0.708 (SE = 0.013, p 90 min increasing more than eightfold from 5.1 to 41.8% in the extremes of the score.
Conclusion: The scoring tool produced in this study was found to be significantly predictive of long operative durations on validation in an external cohort. As such, the tool may have the potential to enable organisations to better organise theatre lists and deliver greater efficiencies in care
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