Abrasive water jet drilling of advanced sustainable bio-fibre-reinforced polymer/hybrid composites : a comprehensive analysis of machining-induced damage responses

This paper aims at investigating the effects of variable traverse speeds on machining-induced damage of fibre-reinforced composites, using the abrasive water jet (AWJ) drilling. Three different types of epoxy-based composites laminates fabricated by vacuum bagging technique containing unidirectional (UD) flax, hybrid carbon-flax and carbon fibre-reinforced composite were used. The drilling parameters used were traverse speeds of 20, 40, 60 and 80 mm/min, constant water jet pressure of 300 MPa and a hole diameter of 10 mm. The results obtained depict that the traverse speed had a significant effect with respect to both surface roughness and delamination drilling-induced damage responses. Evidently, an increase in water jet traverse speed caused an increase in both damage responses of the three samples. Significantly, the CFRP composite sample recorded the lowest surface roughness damage response, followed by C-FFRP, while FFRP exhibited the highest. However, samples of FFRP and hybrid C-FFRP recorded lowest and highest delamination damage responses, respectively. The discrepancy in both damage responses, as further validated with micrographs of colour video microscopy (CVM), scanning electron microscopy (SEM) and X-ray micro-computed tomography (X-ray μCT), is attributed to the different mechanical properties of the reinforced fibres, fibre orientation/ply stacking and hybridisation of the samples.Peer reviewe

Antioxidant Activity of the Phenolic Leaf Extracts from Monechma ciliatum in Stabilization of Corn Oil

The total phenolic content and the antioxidan potential of methanolic extract (ME), ethyl acetate extract (EAE), and hexane extract (HE) from Monechma ciliatum leaves (MCL) were evaluated. The Folin-Ciocalteu, b-carotene bleaching, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and the accelerated oxidation methods were used for evaluation. Both the extraction yield and the antioxidant activity (AOA) were strongly dependent on the solvent. Among the extracts, ME exhibited highest total phenolic compounds (TPC) and IC50 values for DPPH, followed by EAE and HE, respectively. Peroxide value (PV), anisidine value (AV) conjugated dienes (CD), and thiobarbituric acid reactive substances (TBARS) were taken as the parameters for evaluation of stabilization efficacy of MCL extracts and results revealed MCL to be a potent antioxidant for the stabilization of corn oil. As a general trend, increased AOA was observed for increased extract concentration. The predominant phenolic compounds identified by HPLC-DAD in MCL extracts were p-coumaric acid, vanillin and ferulic acid

Prevalence of Group A beta-haemolytic Streptococcus isolated from children with acute pharyngotonsillitis in Aden, Yemen.

OBJECTIVES: To estimate the prevalence of Group A beta-haemolytic streptococcus (GAS) and non-GAS infections among children with acute pharyngotonsillitis in Aden, Yemen, to evaluate the value of a rapid diagnostic test and the McIsaac score for patient management in this setting and to determine the occurrence of emm genotypes among a subset of GAS isolated from children with acute pharyngotonsillitis and a history of acute rheumatic fever (ARF) or rheumatic heart disease (RHD). METHODS: Group A beta-haemolytic streptococcus infections in school-aged children with acute pharyngotonsillitis in Aden, Yemen, were diagnosed by a rapid GAS antigen detection test (RADT) and/or GAS culture from a throat swab. The RADT value and the McIsaac screening score for patient management were evaluated. The emm genotype of a subset of GAS isolates was determined. RESULTS: Group A beta-haemolytic streptococcus pharyngotonsillitis was diagnosed in 287/691 (41.5%; 95% CI 37.8-45.3) children. Group B, Group C and Group G beta-haemolytic streptococci were isolated from 4.3% children. The RADT had a sensitivity of 238/258 (92.2%) and specificity of 404/423 (95.5%) against GAS culture. A McIsaac score of ≥4 had a sensitivity of 93% and a specificity of 82% for confirmed GAS infection. The emm genotypes in 21 GAS isolates from children with pharyngitis and a history of ARF and confirmed RHD were emm87 (11), emm12 (6), emm28 (3) and emm5 (1). CONCLUSION: This study demonstrates a very high prevalence of GAS infections in Yemeni children and the value of the RADT and the McIsaac score in this setting. More extensive emm genotyping is necessary to understand the local epidemiology of circulating strains

The impact of Stieltjes' work on continued fractions and orthogonal polynomials

Stieltjes' work on continued fractions and the orthogonal polynomials related to continued fraction expansions is summarized and an attempt is made to describe the influence of Stieltjes' ideas and work in research done after his death, with an emphasis on the theory of orthogonal polynomials

Antioxidant Activity of the Phenolic Leaf Extracts from Monechma ciliatum in Stabilization of Corn Oil

The total phenolic content and the antioxidan potential of methanolic extract (ME), ethyl acetate extract (EAE), and hexane extract (HE) from Monechma ciliatum leaves (MCL) were evaluated. The Folin-Ciocalteu, b-carotene bleaching, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and the accelerated oxidation methods were used for evaluation. Both the extraction yield and the antioxidant activity (AOA) were strongly dependent on the solvent. Among the extracts, ME exhibited highest total phenolic compounds (TPC) and IC50 values for DPPH, followed by EAE and HE, respectively. Peroxide value (PV), anisidine value (AV) conjugated dienes (CD), and thiobarbituric acid reactive substances (TBARS) were taken as the parameters for evaluation of stabilization efficacy of MCL extracts and results revealed MCL to be a potent antioxidant for the stabilization of corn oil. As a general trend, increased AOA was observed for increased extract concentration. The predominant phenolic compounds identified by HPLC-DAD in MCL extracts were p-coumaric acid, vanillin and ferulic acid

The Global Longitudinal Study of Osteoporosis in Women (GLOW): rationale and study design

SUMMARY: The Global Longitudinal study of Osteoporosis in Women (GLOW) is a prospective cohort study involving 723 physicians and 60,393 women subjects >or=55 years. The data will provide insights into the management of fracture risk in older women over 5 years, patient experience with prevention and treatment, and distribution of risk among older women on an international basis. INTRODUCTION: Data from cohort studies describing the distribution of osteoporosis-related fractures and risk factors are not directly comparable and do not compare regional differences in patterns of patient management and fracture outcomes. METHODS: The GLOW is a prospective, multinational, observational cohort study. Practices typical of each region were identified through primary care networks organized for administrative, research, or educational purposes. Noninstitutionalized patients visiting each practice within the previous 2 years were eligible. Self-administered questionnaires were mailed, with 2:1 oversampling of women >or=65 years. Follow-up questionnaires will be sent at 12-month intervals for 5 years. RESULTS: A total of 723 physicians at 17 sites in ten countries agreed to participate. Baseline surveys were mailed (October 2006 to February 2008) to 140,416 subjects. After the exclusion of 3,265 women who were ineligible or had died, 60,393 agreed to participate. CONCLUSIONS: GLOW will provide contemporary information on patterns of management of fracture risk in older women over a 5-year period. The collection of data in a similar manner in ten countries will permit comparisons of patient experience with prevention and treatment and provide insights into the distribution of risk among older women on an international basis

Is Adherence to Imatinib Mesylate Treatment Among Patients with Chronic Myeloid Leukemia Associated with Better Clinical Outcomes in Qatar?

Background: Despite the revolutionary success of introducing tyrosine kinase inhibitors (TKIs), such as imatinib mesylate (IM), for treating chronic myeloid leukemia (CML), a substantial proportion of patients' treatments fail. Aim: This study investigates the correlation between patient adherence and failure of TKIs' treatment in a follow-up study. Methods: This is a follow-up study of a new cohort of CML patients. Adherence to IM is assessed using the Medication Event Monitoring System (MEMS 6 TrackCap, AARDEX Ltd). The 9-item Morisky Medication Adherence Scale, medication possession ratio (MPR) calculation, and the electronic medical records are used for identifying potential factors that influence adherence. Clinical outcomes are assessed according to the European LeukemiaNet 2013 guidelines via reverse transcriptase quantitative polymerase chain reaction measurement of the level of BCR-ABL1 transcripts in peripheral blood. Response is classified at the hematological, cytogenetic, and molecular levels into optimal, suboptimal, or failure. Results: A total of 36 CML patients (5 citizens and 31 noncitizen residents) consented to participate in the study. The overall mean MEMS score was 89. Of the 36 patients, 22 (61%) were classified as adherent (mean: 95) and 14 (39%) were classified as nonadherent (mean: 80.2). Adherent patients were significantly more likely to obtain optimal response (95%) compared to the nonadherent group (14.3%; P < 0.0001). The rate of poor adherence was as high as 39% using MEMS, which correlates with 37% treatment failure rate. The survey results show that 97% of patients increased the IM dose by themselves when they felt unwell and 31% of them took the missing IM dose when they remembered. Other factors known to influence adherence show that half of patients developed one or more side effects, 65% of patients experienced lack of funds, 13% of patients declared unavailability of the drug in the NCCCR pharmacy, and 72% of patients believed that IM would cure the disease. The MPR results reveal that 16% of patients had poor access to treatment through the hospital pharmacy. Discussion and conclusion: This is the first prospective study to evaluate CML patients' adherence and response to IM in Qatar. The high rate of treatment failure observed in Qatar is explained by poor adherence. An economic factor (unaffordable drug prices) is one of the main causes of nonadherence and efforts should be made locally to improve access to medication for cancer diseases. Other risk factors associated with poor adherence could be improved by close monitoring and dose adjustment. Monitoring risk factors for poor adherence and patient education that include direct communication between the health-care teams, doctors, nurses, pharmacists, and patients are essential components for maximizing the benefits of TKI therapy and could rectify this problem. The preliminary results show that patients' response to treatment may be directly linked to patients' adherence to treatment. However, further in-depth and specific analysis may be necessary in a larger cohort

Morphological and molecular evaluation of some Egyptian pomegranate cultivars

Six Egyptian pomegranate (Punica granatum L.) cultivars were characterized by fruit characteristics (physical and chemical) and two molecular markers; Inter simple sequence repeat (ISSR) and amplified fragment length polymorphism (AFLP). Genetic diversity of the pomegranate genotypes was evaluated. Physical fruit traits were determined (weight, volume and diameter), calyx [diameter, length (mm) and Carpels number], fruit firmness (Newton), peel as (weight and thickness), arils weight (g), volume of juice (ml), seeds [fresh and dry weight (g)], and color parameter of (fruit skin, internal peel, arils, juice and seeds). The chemical traits such as soluble solids contents (SSC), vitamin C content, anthocyanin content, pH, and titratable acidity (TA) were assessed and wide variations were observed in each of these traits among the studied cultivars. The genetic variability and relationships among six Egyptian pomegranate cultivars were tested using ISSR and AFLP analyses. The level of polymorphism across cultivars was 53 and 90.7% as revealed by ISSR and AFLP, respectively. ISSR and AFLP revealed different genetic similarities among the six pomegranate cultivars. Each analysis differs not only in its underlying principle, but also in their in-formativeness with regard to the type and amount of polymorphism detected. Genetic similarity matrices estimated from ISSR and AFLP data, showed similarity coefficients to range from 0.77 to 0.94 and 0.33 to 0.73, respectively. ISSR and AFLP characterized the six pomegranate cultivars by a large number of unique markers being 23 and 46 unique markers, respectively. The fruit weight ranged between 479.4 to 185 g of ʻNab El Gamalʼ and ʻAssuityʼ, the firmness was 79.98 of ʻNab El Gamalʼ and 71.84 Newton of ʻManfaloutyʼ cv. The fruit peel thickness varied from 0.6 mm ʻArabyʼ, ʻHegazyʼ and ʻWardiʼ to 0.3 mm ʻAssuityʼ. The arils weight ranged from 87.5 to 275 g of ʻAssuityʼ and ʻNab El Gamalʼ cvs. The percentage net of arils weight/ fruit weight was the highest (59.34% of ʻManfaloutyʼ cv). The juice volume ranged from 62.41 to 71.81 ml/100 g arils for ʻ Wardiʼ and ʻNab El Gamalʼ cvs. The SSC content ranged between 16.01 ʻHegazyʼ and 12.55% ʻAssuityʼ. V.C. content ranged from 3.21 to 14 mg. vitamin/100 ml juice of ʻNab El Gamalʼ and ʻAssuityʼ. The anthocyanin content ranged from 1.47 to 10.03 for ʻArabyʼ and ʻHegazyʼ. The pH values varied from 3.3 (Wardi) to 2.9 (Araby). The Egyptain cultivars of pomegranate have a wide variation in the morphological and chemical characteristics for many uses of fresh fruit and of industry purpose.Keywords: Morphological and chemical fruits characterization, pomegranate, inter simple sequence repeat (ISSR), DNA markers, amplified fragment length polymorphism (AFLP)African Journal of Biotechnology, Vol. 13(2), pp. 226-237, 8 January, 201

Hospital and community isolates of uropathogens at a tertiary hospital in South Africa

Aim. To investigate the profile of common uropathogensisolated from urine specimens submitted to the diagnostic microbiology laboratory at a tertiary teaching hospital and assess their antimicrobial susceptibility patterns to commonly used antimicrobial agents.Methods. We conducted a retrospective analysis of laboratoryreports for all urine specimens submitted for investigations over a 1-year period. Isolates were tested by means of the Kirby-Bauer disc diffusion method for susceptibility to amoxicillin, ciprofloxacin, gentamicin, co-trimoxazole and nitrofurantoin, and for extended-spectrum beta-lactamase (ESBL) production.Results. Out of the total specimens (N=2 203) received over the 1-year study period, 51.1% (1 126) of the urine samples were culture-positive, the majority (65.4%) having come from females. The most common isolate was Escherichia coli (39.0%) followed by Klebsiella species (20.8%) and Enterococcus faecalis (8.2%). The  ram-negative isolates displayed a very high level of resistance to amoxicillin (range 43 - 100%) and co-trimoxazole (range 29 - 90%), whereas resistance to gentamicin (range 0 - 50%) and ciprofloxacin (range 0 - 33%)was lower. E. coli isolates were susceptible to nitrofurantoin (94%), and ESBL production was significantly higher (p=0.01) in the hospital isolates, compared with those from the community referral sites.Conclusions. The culture-positive rate for uropathogens washigh, with a greater incidence among females. E. coli was the most common aetiological agent identified, and remained susceptible to nitrofurantoin. Resistance levels to amoxicillin and co-trimoxazole were very high for all Gram-negative isolates, and it is recommended that these antibiotics should not be used for the empiric treatment of urinary tract infections

Growth response of eight tropical turfgrass species to salinity

Irrigation seawater of different salinity levels (0, 24, 48 and 72 dSm-1) were applied to experimental plants grown in a plastic pots filled with a mixture of sand and peat (9:1). The results were analyzedusing SAS and treatment means were compared using LSD Test. The results indicated that Paspalum vaginatum (seashore paspalum) (SP), Zoysia matrella (manilagrass) (MG), Pasplaum vaginatum local(SPL), Cynodon dactylon (common bermuda) (CB), Cynodon dactylon (bermuda greenless park) (GLP), Eremochloa ophiuroides (centipede) (CP), Axonopus compressus (cow grass) (CG) and Axonopusaffinis (narrowleaf carpet grass) (NCG) experienced a 50% shoot growth reduction at the EC of 39.8, 36.5, 26.1, 25.9, 21.7, 22.4, 17.0 and 18.3 dSm-1, respectively, and a 50% root growth reduction at the ECof 49.4, 42.1, 29.9, 29.7, 26.0 24.8, 18.8 and 20.0 dSm-1, respectively. The ranking for salinity tolerance of selected grasses was  SP>MG>SPL>CB>GLP>CP>NCG>CG. The results indicate the importance of the selection of turfgrass varieties according to the soil salinity and seawater salinity levels to be used for irrigation