18 research outputs found

    End Zone Reinforcement for Pretensioned Concrete Girders

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    In this study, a literature review was conducted to establish the background of current specifications and to evaluate the applicability of various theories and methods for design of end zone reinforcement. Analytical methods reviewed in this paper include finite element analysis, strut-and-tie modeling, and the Gergely-Sozen equivalent beam method. Previous experimental work combined with work conducted as part of this study was used to correlate between various theoretical and experimental results. This paper illustrates that no single theoretical method adequately represents the complex behavior at the end of a pretensioned concrete member. A general semi-empirical design procedure is proposed here. It is based on theoretical behavior and experimental observation. Standard reinforcement details are given. The proposed procedure could result in significant reduction in the amount of reinforcement while maintaining acceptable crack control at the member end. Application of the proposed procedure to highly pretensioned bridge girders is demonstrated

    EFFECT OF BIOMPHALARIA ALEXANDRINA SNAILS INFECTED BY BACILLUS THURINGIENSIS KURSTAKI ON THREE SUCCESSIVE GENERATIONS OF SCHISTOSOMA MANSONI

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    The effect of infection of Biomphalaria alexandrina snails with Bacillus thurin-giensis kurstaki on various stages of Schistosoma mansoni life cycle was studied for three successive generations. Thus, two groups of snails were exposed to a sublethal concentration of the bacteria (0.08 gm/L water) containing 32000 IU/mg, for one week and to schistosome miracidia. One group was exposed to the miracidia before bacterial infection, while the other group to the miracidia after the bacterial infec-tion. Cercariae produced from each group of snails were used to infect albino mice. The infection of snails and mice with the parasite was repeated for three generations of the parasite. In the first case, data obtained show that the schistosome infection rate of snails was considerably reduced being 60%, 18%, and 66.6% versus 90 % , 92% and 90% in untreated control snails in the three generations of the parasite, re-spectively. Meanwhile, the mean prepatent period was extended being 29.1 4.3 days, 33 1 days and 38.5 2.5 days versus 27 days in the control group. The num-ber of worms recovered from infected mice showed reduction of 52 %, 78.4% and 58.6%, respectively. In the second case, the infection rate of snails was 40%, 16% and 73.7% for the three successive parasite generations and the prepatent period was 32 1 days, 32 2.3 days and 35 2.8 days, respectively. The reduction percentage of the recovered worms was 34.8, 73.6 and 72.9 in the sccessive generations, respec-tively. The present results prove that infecting B.alexandrina snails with a sublethal concentration of B. thuringiensis kurstaki bacteria exhibits clear negative effect on the transmission of S. mansoni in three successive generations. So, it could be rec-ommended to use B. thuringiensis kurstaki as a potential biocontrol agent against S. mansoni

    The impact of immediate breast reconstruction on the time to delivery of adjuvant therapy: the iBRA-2 study

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    Background: Immediate breast reconstruction (IBR) is routinely offered to improve quality-of-life for women requiring mastectomy, but there are concerns that more complex surgery may delay adjuvant oncological treatments and compromise long-term outcomes. High-quality evidence is lacking. The iBRA-2 study aimed to investigate the impact of IBR on time to adjuvant therapy. Methods: Consecutive women undergoing mastectomy ± IBR for breast cancer July–December, 2016 were included. Patient demographics, operative, oncological and complication data were collected. Time from last definitive cancer surgery to first adjuvant treatment for patients undergoing mastectomy ± IBR were compared and risk factors associated with delays explored. Results: A total of 2540 patients were recruited from 76 centres; 1008 (39.7%) underwent IBR (implant-only [n = 675, 26.6%]; pedicled flaps [n = 105,4.1%] and free-flaps [n = 228, 8.9%]). Complications requiring re-admission or re-operation were significantly more common in patients undergoing IBR than those receiving mastectomy. Adjuvant chemotherapy or radiotherapy was required by 1235 (48.6%) patients. No clinically significant differences were seen in time to adjuvant therapy between patient groups but major complications irrespective of surgery received were significantly associated with treatment delays. Conclusions: IBR does not result in clinically significant delays to adjuvant therapy, but post-operative complications are associated with treatment delays. Strategies to minimise complications, including careful patient selection, are required to improve outcomes for patients

    PRECAST POST-TENSIONED SEGMENTAL POLE SYSTEM: U.S. Patent No. US 6,851,231 B2

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    A precast post-tensioned segmental pole system capable of supporting a load is provided. The pole system includes a plurality of pole segments that use connectors and strands to anchor them together. The strands extend within a cavity formed in the pole segments and are external to the wall structure of the pole segments. The strands may be coupled between both of the pole segments, or be anchored to a connector. The connector includes an upper piece that is coupled to one pole segment, and a lower piece that is coupled to the other pole segment. Upper and lower pieces interlock with each other to join the pole segments to one another. The strands are placed in tension so that pole system is capable of withstanding forces imposed by the load

    Letrozole plus misoprostol versus misoprostol alone in the induction of anembryonic missed abortion: a randomized controlled trial conducted in Upper Egypt

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    Abstract Background A missed abortion is a spontaneous abortion in which the embryo or fetus has already died but has remained in the uterus for days or weeks with a closed cervical ostium. Termination of pregnancy could be achieved either by surgical evacuation or medical or expectant management. Letrozole is a third-generation aromatase inhibitor. According to many recent studies, letrozole given for three days before the administration of misoprostol was more effective than misoprostol alone at inducing abortion. Our study compared the efficacy of various letrozole regimens (10 mg/d for three days and a single dose of 20 mg) combined with misoprostol vs. misoprostol alone in inducing abortion. To find the most efficient regimen of letrozole administered before misoprostol to induce an abortion. Methodology This prospective, parallel, three-arm, single-blinded, allocation-concealed randomized controlled trial was conducted in Sohag Teaching Hospital in Upper Egypt. We randomly divided 105 patients with anembryonic missed abortion (up to 63 days gestation) with no history of medical disorders or a history of allergies to misoprostol or letrozole into three equal groups (a single-dose letrozole group, a multiple-dose letrozole group, and a misoprostol-only group). The complete abortion rate, incomplete abortion rate, failure to abort rate, and induction-to-abortion interval were all collected. All statistical calculations were performed using the computer program SPSS (Statistical Package for the Social Science, SPSS Inc., Chicago, IL, USA). Results The complete abortion rate was significantly higher in the single-dose letrozole and multiple-dose letrozole groups than in the misoprostol group (p values = 0.0455 and 0.001, respectively). On the other hand, there was no significant difference in the complete abortion rate between the single-dose group and the multiple-dose letrozole group (p-value = 0.1713). The time to complete abortion was significantly shorter in the single-dose and multiple-dose letrozole groups than in the misoprostol group (p values = 0.0036 and 0.0049, respectively). On the other hand, there was no significant difference in the time to complete abortion between the single-dose letrozole group and the multiple-dose letrozole group (P = 0.532). Conclusion Single- and multiple-dose letrozole regimens followed by misoprostol had a higher rate and a shorter time to complete abortion than misoprostol alone. Trial registration The trial is registered at gov with the name “letrozole and abortion” and the identifier “NCT05198050”. The date of registration was April 1, 2022, registered prospectively. URL: https://register.clinicaltrials.gov/prs/app/action/ViewOrUnrelease?uid=U0004GED&ts=25&sid=S000BPDQ&cx=43mobl

    Gene Expression Changes for Antioxidants Pathways in the Mouse Cochlea: Relations to Age-related Hearing Deficits

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    Age-related hearing loss – presbycusis – is the number one neurodegenerative disorder and top communication deficit of our aged population. Like many aging disorders of the nervous system, damage from free radicals linked to production of reactive oxygen and/or nitrogen species (ROS and RNS, respectively) may play key roles in disease progression. The efficacy of the antioxidant systems, e.g., glutathione and thioredoxin, is an important factor in pathophysiology of the aging nervous system. In this investigation, relations between the expression of antioxidant-related genes in the auditory portion of the inner ear – cochlea, and age-related hearing loss was explored for CBA/CaJ mice. Forty mice were classified into four groups according to age and degree of hearing loss. Cochlear mRNA samples were collected and cDNA generated. Using Affymetrix® GeneChip, the expressions of 56 antioxidant-related gene probes were analyzed to estimate the differences in gene expression between the four subject groups. The expression of Glutathione peroxidase 6, Gpx6; Thioredoxin reductase 1, Txnrd1; Isocitrate dehydrogenase 1, Idh1; and Heat shock protein 1, Hspb1; were significantly different, or showed large fold-change differences between subject groups. The Gpx6, Txnrd1 and Hspb1 gene expression changes were validated using qPCR. The Gpx6 gene was upregulated while the Txnrd1 gene was downregulated with age/hearing loss. The Hspb1 gene was found to be downregulated in middle-aged animals as well as those with mild presbycusis, whereas it was upregulated in those with severe presbycusis. These results facilitate development of future interventions to predict, prevent or slow down the progression of presbycusis

    Correlation between <i>Txnrd1</i> gene expression and audiological measurements.

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    <p><sup>*</sup> denotes statistical significance at 0.05 level;</p><p><sup>**</sup> at the 0.01 level;</p><p><sup>***</sup> at the 0.001 level.</p

    Correlation between Gpx6 gene expression and audiological measurements.

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    <p><sup>*</sup> denotes statistical significance at 0.05 level;</p><p><sup>**</sup> at the 0.01 level.</p
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