168 research outputs found

    Behavior of Hexagonal Concrete-Filled Double-Skin Steel Short Columns under the Effect of Axial Compression

    Get PDF
    Concrete-filled double skin tubular (CFDST) columns involve a tube-‌in-‌tube arrangement, where the steel sections can be round, square or rectangular hollow sections, with the annulus between the hollow sections filled with concrete. To date there have been no significant applications of hexagonal concrete-filled double skin tubular columns (HCFDST) with inner circular tubes worldwide, partly due to the lack of design provisions. This paper addresses the compressive performance of these columns. To obtain the structural behavior of HCFDST columns, a finite element analysis was conducted. To indicate the accuracy and the reliability of the model, the proposed FEM model was verified by the available experimental data for HCFDST. Columns were employed to conduct parametric studies, the effects of various parameters on the load-displacement response of HCFDST short columns are studied by using the validated FE model. A new formula to determine ultimate load for regular HCFDST short columns in compression has been proposed in this study

    The outcomes of Skeletonized and Pedicled Internal Thoracic Artery in Patients undergoing coronary artery bypass grafting: a randomized clinical study

    Get PDF
    Background: Internal thoracic artery became the cornerstone graft in coronary artery bypass grafting. This study aimed to investigate sternal healing and wound infection in patients undergoing coronary artery bypass graft (CABG) surgery using skeletonized versus pedicled internal thoracic artery. Methods: 100 patients who underwent isolated CABG were divided into two groups; skeletonized internal thoracic artery (ITA) (50 patients) and pedicled internal thoracic artery (50 patients). The postoperative assessment was performed three months after surgery. Physical and radiological examinations were performed after surgery to assess sternal healing. Results: There was no significant difference in patients’ demographics between groups. Skeletonized group had more diabetic patients (65% vs 44%; p= 0.016). There was no significant difference between the two groups regarding the number of grafts (2.72 ± 0.89 vs. 2.68 ± 0.90; skeletonized vs pedicled group; p= 0.84). Harvesting time was longer in the skeletonized group (55.69 ± 8.80 vs. 44.28 ± 6.95 minutes; p=0.09). Superficial wound infection occurred more frequently in the pedicled group (24% vs. 8%; p=0.03). Conclusion: Skeletonization of the internal thoracic artery conduits lowers the risk of superficial and deep sternal wound infection in patients undergoing CABG compared to the pedicled technique. However, skeletonization of internal thoracic artery conduits prolongs the operation time and requires more surgical skills

    Intrauterine instillation of granulocyte colony stimulating factor for infertile women with thin endometrium in intrauterine insemination cycle: a non-randomized clinical trial

    Get PDF
    Background: Endometrial thickness is one of the major factors for a receptive endometrium and successful implantation. Thin endometrium, generally measuring <7 mm are thought to be less able to support implantation and pregnancy. Several adjuvants have been investigated for their efficacy on thin endometrium in assisted reproductive technology. Granulocyte colony stimulating factor (G-CSF) is a glycoprotein that promotes endometrial stromal cell decidualization via cyclic adenosine monophosphate mediator and induces endometrial proliferation and differentiation. This study was done to evaluate the effect of G-CSF in improving endometrial thickness and pregnancy rate in infertile patients undergoing stimulated IUI (intrauterine instillation) having thin endometrium.Methods: This was a non-randomized clinical trial done among 40 infertile patients with thin endometrium (<7 mm) on the day of ovulation trigger in stimulated IUI patients. Study subjects were non randomly allocated into 2 groups. In group A 20 patients received intrauterine instillation of G-CSF (300 mcg/0.5 ml) via intrauterine catheter on triggering day and in group B another 20 patients received intrauterine instillation of 0.5 ml normal saline in the same procedure. After 48 hours endometrial thickness was measured in both groups. IUI was done on the same day. Pregnancy was detected by serum beta hCG level after 14 days of IUI.Results: In both groups most of the respondents were aged between 30-34 years, 14 (70%) in group A and 11 (55%) in group B. The mean±SD of age 32.4±3.1 in group A, 32.2±3.4 in group B and P value was 0.9. In group A the minimum endometrial thickness on day of ovulation trigger was 4.4 mm and after 48 hours of treatment with G-CSF, it was found 6.3 mm. The maximum endometrial thickness recorded in group A was 6.9 mm and it also increased to 8.7 mm after G-CSF treatment and followed by in group B min thickness 4.8 mm increase to 5.2 mm and max thickness 6.8 mm increased to 8.7 mm. The mean±SD of ET (mm) on the day of ovarian trigger was 5.8±0.8 which increased to 7.4±0.8 in group A and followed by 5.9±0.6 to 7.1±0.9 in group B. ET mean change (mean±SD) for group A was 1.6±0.7 which was greater than the group B 1.3±0.8. Pregnancy rate was 2 (10%) in group A and 1(5%) in group B.Conclusions: Mean increase in endometrial thickness and pregnancy rate was higher in G-CSF group than normal saline group, but the difference was not statistically significant

    External beam radiotherapy and intracavitary brachytherapy is an acceptable treatment for locally advanced carcinoma of the uterine cervix

    Get PDF
    Background: Cervical carcinoma is the second most common neoplasm in women worldwide and is the most frequent cancer among women in Bangladesh. In recent years, High Dose Rate (HDR) brachytherapy in combination with External Beam Radiotherapy (EBRT) has been popular in the management of cancers of uterine cervix.Objectives: To evaluate the effectiveness and acute toxicity of four fractions high dose rate intracavitary brachytherapy following pelvic external beam radiotherapy in the treatment of locally advanced cervical carcinoma. Methods: Bangabandhu Sheikh Mujib Medi­cal University & NICRH chosen as a research place for EBRT and HOR brachytherapy. A typical radiotherapy treatment involves daily inadiation for several weeks. Whole pelvis was treated with total dose of SO Gy in 5 weeks. Patients were treated once a day, 5 days a week with a daily fraction size of 2.0 Gy. EBRT: Pelvic radiotherapy dose is 50 Gy in 25 fractions (2.0 Gy per fraction) over 5 weeks. HDR brachytberapy dose is 7 Gy per fraction, total 4 fractions, each in a week over 4 weeks. Results: Ninety-eight patients were entered in the study. Three patients were excluded due to active non-malignant diseases. One patient had active tuberculosis, two patients had severe skin reactions and two patients withdrew following the first HDR application. The remaining Ninety patients were analyzed. Ninety patients completed the prescribed treatment and were evaluated. Eighty had complete response with relief of symptoms, negative Pap-smear and no clinical signs of persistence disease at 3 months. Ten patients had a positive Pap-smear with clinical signs of persis­tence disease. Patients were evaluated before statting treatment with EBRT and before starting treatment with HDR ICBT. Conclusion: It can be easily concluded that 4 fractions of HDR ICBT, 7 Gy each weekly and pelvic EBRT can effectively and safely control locally advanced carcinoma of the uterine cervix. So that EBRT and HDR ICBT is an acceptable treatment for locally advanced carcinoma of the uterine cervix. Careful attention to normal tissue doses such as the rectum, bladder, and small bowel is important in the treatment of locally advanced cervical cancer

    External beam radiotherapy and intracavitary brachytherapy is an acceptable treatment for locally advanced carcinoma of the uterine cervix

    Get PDF
    Background: Cervical carcinoma is the second most common neoplasm in women worldwide and is the most frequent cancer among women in Bangladesh. In recent years, High Dose Rate (HDR) brachytherapy in combination with External Beam Radiotherapy (EBRT) has been popular in the management of cancers of uterine cervix.Objectives: To evaluate the effectiveness and acute toxicity of four fractions high dose rate intracavitary brachytherapy following pelvic external beam radiotherapy in the treatment of locally advanced cervical carcinoma. Methods: Bangabandhu Sheikh Mujib Medi­cal University & NICRH chosen as a research place for EBRT and HOR brachytherapy. A typical radiotherapy treatment involves daily inadiation for several weeks. Whole pelvis was treated with total dose of SO Gy in 5 weeks. Patients were treated once a day, 5 days a week with a daily fraction size of 2.0 Gy. EBRT: Pelvic radiotherapy dose is 50 Gy in 25 fractions (2.0 Gy per fraction) over 5 weeks. HDR brachytberapy dose is 7 Gy per fraction, total 4 fractions, each in a week over 4 weeks. Results: Ninety-eight patients were entered in the study. Three patients were excluded due to active non-malignant diseases. One patient had active tuberculosis, two patients had severe skin reactions and two patients withdrew following the first HDR application. The remaining Ninety patients were analyzed. Ninety patients completed the prescribed treatment and were evaluated. Eighty had complete response with relief of symptoms, negative Pap-smear and no clinical signs of persistence disease at 3 months. Ten patients had a positive Pap-smear with clinical signs of persis­tence disease. Patients were evaluated before statting treatment with EBRT and before starting treatment with HDR ICBT. Conclusion: It can be easily concluded that 4 fractions of HDR ICBT, 7 Gy each weekly and pelvic EBRT can effectively and safely control locally advanced carcinoma of the uterine cervix. So that EBRT and HDR ICBT is an acceptable treatment for locally advanced carcinoma of the uterine cervix. Careful attention to normal tissue doses such as the rectum, bladder, and small bowel is important in the treatment of locally advanced cervical cancer

    Effects of autologous stem cell therapy for fertility enhancement among women with premature ovarian insufficiency

    Get PDF
    Background: Premature ovarian insufficiency (POI) is a condition where the ovary loses its normal reproductive potential earlier than 40 years, compromising fertility. There is no treatment for POI, only ovum or embryo donation. Autologous stem cell ovarian transplant (ASCOT) may be a procedure that creates new eggs in the ovaries of women with POI. The aim of the study was to find out the efficacy of ASCOT in patients suffering from POI. Methods: A total of 50 patients were included according to inclusion and exclusion criteria in this prospective observational study. POI was confirmed with low levels of anti-mullerian hormone (AMH) (<0.5 ng/dl), high level of follicle stimulating hormone (FSH) >25 ng/ml, and or a low number of antral follicle count (AFC) (<3 in each ovary). Results: Results showed that after stem cell therapy, mean AMH values increased by 0.48±0.306 and mean FSH values increased by 2.73±3.98 but the difference was not statistically significant. AFC values significantly decreased by 1.33±0.625 at 1st post-stem-cell cycle. During the second cycle, AMH and AFC increased by 0.110±0.051 and 4.63±1.49, respectively, and FSH decreased by 7.4±2.78. In third cycle, AMH & FSH was significantly increased by 0.820±0.44 & 4.120±0.470 and FSH has been decreased by 2.150±3.625. The increase in AMH & AFC was statistically significant, and the decrease in FSH was not statistically significant compared to baseline values. Conclusions: The study showed that autologous stem cell therapy can have a significant effect on women’s ovarian function and fertility. It showed that ASCOT can increase AMH and AFC, and decrease FSH in patients with POI, with a total pregnancy rate of 4% after the third cycle follow-up

    Prognosis of Elevated Serum Ferritin in Allogeneic-HCT

    Get PDF
    Introduction: Serum ferritin was demonstrated to be a useful tool to predict the risk in patients who undergo hematopoietic stem cell transplantation (HCT). Still it is not clear if its predictive value solely represents iron overload (IO) and published results are sometimes contradictory. So the objective of present study was to determine relationship between elevated pre-HCT serum ferritin levels, morbidity and mortality after allogeneic hematopoietic stem cell transplantation (allo-HCT) on one side, and its correlations with various risk indexes which were developed recently to predict outcomes after allo-HCT on the other side. Patients and Methods: In this retrospective study we have reviewed medical records of one hundred six consecutive patients (52 males and 54 females), with a median age of 32 years (range, 5 to 60), who underwent allo-HCT with unmanipulated grafts between Jan 2013 and Dec2014. We retrieved pre-allo-HCT serum ferritin levels and also calculated risk indexes before HCT. The incidence of complications and outcomes after allo-HCT was assessed. The median follow-up period was 12 (range, 4-27) months after allo-HCT. Results: We have determined a cuttoff ferritin level of 500 ng/mL for early complications and 737 for outcomes. We found increased incidence of number of febrile neutropenic episodes (P =0.02), number of bacterial infection episodes (P =0.009), pneumonias (P =0.039), slower period of neutrophil engraftment (P=0.032), demand for multiple red blood cell (RBC) transfusions (P =0.002) within 100 days post transplantation. A significant association was found between pre-transplant ferritin concentrations and different risk indexes; European Group for Blood and Marrow Transplantation (EBMT) risk score (P=0.001), Hematopoietic cell transplantation comorbidity index (HCT-CI) (P=0.003), Pre-transplant Assessment of Mortality (PAM) score (P=0.007) and disease risk (DR) (P =0.037). Conclusion: On the one hand we did confirmed that even moderate serum ferritin elevation is associated with increased incidence of infections, slower period to engraftment and increasing demand of RBC units transfusions, but strong correlation with pre-transplant indexes that take into account disease risk raises the question if IO is the only factor that adversely affect the outcome of HCT in patients with increased ferritin. This should be studied in prospective trials

    Association of serum leptin and ghrelin levels with smoking status on body weight: a systematic review and meta-analysis

    Get PDF
    Background and aimsSmoking cigarettes is a major global health problem that affects appetite and weight. The aim of this systematic review was to determine how smoking affected plasma leptin and ghrelin levels.MethodsA comprehensive search of PubMed, Scopus, Web of Science, and Ovid was conducted using a well-established methodology to gather all related publications.ResultsA total of 40 studies were included in the analysis of 11,336 patients. The overall effect showed a with a mean difference (MD) of −1.92[95%CI; −2.63: −1.20] and p = 0.00001. Subgroup analysis by study design revealed significant differences as well, but with high heterogeneity within the subgroups (I2 of 82.3%). Subgroup by sex showed that there was a significant difference in mean difference between the smoking and non-smoking groups for males (MD = −5.75[95% CI; −8.73: −2.77], p = 0.0002) but not for females (MD = −3.04[95% CI; −6.6:0.54], p = 0.10). Healthy, pregnant, diabetic and CVD subgroups found significant differences in the healthy (MD = −1.74[95% CI; −03.13: −0.35], p = 0.01) and diabetic (MD = −7.69[95% CI, −1.64: −0.73], p = 0.03). subgroups, but not in the pregnant or cardiovascular disease subgroups. On the other hand, the meta-analysis found no statistically significant difference in Ghrelin serum concentration between smokers and non-smokers (MD = 0.52[95% CI, −0.60:1.63], p = 0.36) and observed heterogeneity in the studies (I2 = 68%).ConclusionThis study demonstrates a correlation between smoking and serum leptin/ghrelin levels, which explains smoking’s effect on body weight.Systematic review registrationhttps://www.crd.york.ac.uk/ prospero/display_record.php, identifier (Record ID=326680)

    Photoelectrocatalytic reduction of CO2 to methanol over CuFe2O4@PANI photocathode

    Get PDF
    The present study was aimed to convert CO2 into methanol which not only addresses the potential solution for controlling the CO2 concentration level in the atmosphere but also offers an alternative approach for the production of renewable energy source. In this perspective, a hybrid photocatalyst, PANI@CuFe2O4 was synthesized, characterized and used as a photocathode for photoelectrocatalytic (PEC) reduction of CO2 to methanol in aqueous medium at an applied potential of −0.4 V vs NHE under visible light irradiation. The combination of PANI with CuFe2O4 greatly increased the PEC CO2 reduction to methanol owing to enhance the CO2 chemisorption capacity by the photocathode surface and at the same time facilitated the separation of photogenerated electron-hole (e−/h+) pairs. The incident photon to current efficiency (IPCE) and quantum efficiency (QE) for methanol formation in PEC CO2 reduction could be achieved as 7.1 and 24.0% respectively. The rate of formation of methanol in PEC CO2 reduction was found as 49.3 μmol g−1h−1 with 73% Faradaic efficiency. Compared to photocatalytic reaction, the PEC results demonstrated that the applied potential could effectively separate the photogenerated e−/h+ pairs and therefore, enhanced the PEC CO2 reduction activity of the hybrid photocatalyst

    Hetero-structure CdS-CuFe2O4 as an efficient visible light active photocatalyst for photoelectrochemical reduction of CO2 to methanol

    Get PDF
    In the present paper, hetero-structured CdS–CuFe2O4 nanocomposite was synthesized by a facial method to convert CO2 to methanol in the photoelectrochemical (PEC) system. The synthesized catalysts were characterised by XRD, Raman spectroscopy, TEM, FESEM, EDX, XPS, UV–vis and PL spectroscopy. The CdS–CuFe2O4 photocatalyst showed ~6 times higher photocurrent compared to the CuFe2O4 at −0.35 V vs. NHE of bias potential under CO2 environment as revealed by chronoamperometry results. Incident photon to current efficiency (IPCE) for CuFe2O4 and CdS–CuFe2O4 at 470 nm were found as 7.28 and 12.09%, respectively which clearly indicates the proficiency of CdS–CuFe2O4 heterojunction to absorb the visible light resulting in e−/h+ generation and the charge transfer during PEC CO2 reduction. Products in aqueous and gas phases were analysed which confirmed the selective production of methanol with trace amounts of H2 and CO. The CdS–CuFe2O4 catalyst demonstrated 72% and 16.9% of Faradaic and quantum efficiencies, respectively in terms of methanol production where a methanol yield of 23.80 μmole/Lcm2 was achieved in CO2 saturated aqueous solution of NaHCO3 (0.1 M). Detailed investigation revealed that the conduction band (CB) of the CdS in the heterojunction catalyst could act as a CO2 reduction site by trapping photogenerated electrons from the highly photosensitive CuFe2O4 while the water oxidation could take place at the valance band (VB) of CuFe2O4
    • …
    corecore