343 research outputs found
Improved confinement of reinforced concrete columns
AbstractTraditional steel ties reinforcement cannot provide superior confinement for reinforced concrete (RC) columns due to the constraints on tie spacing and disturbance of concrete continuity. This paper presents a practical confinement configuration consisting of single Expanded Metal Mesh (EMM) layer in additional to regular tie reinforcement. The EMM layer is warped above ties. The proposed transverse reinforcement, with various volumetric ratios of ties, was investigated in sixteen square short RC column specimens categorized in two groups according to their slenderness ratios. The specimens were cast in vertical position simulating the construction field and they were tested under concentric compression till failure. The results indicated that the columns, confined with proposed lateral reinforcement, revealed significant improvement in the strength and ductility. Also, high reduction in ties volumetric ratio with no loss in ultimate load could be achieved by installing the EMM layer
A Practical Fast Acting Control Scheme For Fuzzy Logic-Based Voltage Stabilization Control
This paper presents a simplified control model for stabilizing a load voltage using a switched reactor in parallel with a fixed capacitor of static VAR compensator. Two IGBTâs are used to control the reactance of the switched reactor. A uniform pulse width modulation is used for controlling the two switches. The compensator has a simple control circuit and structure. A complete modeling and numerical simulation for the proposed systems is presented. A high speed Digital Signal Processor is used for implementing proportional-integral (PI) and fuzzy load voltage controllers. Experimental results indicate the superiority of fuzzy logic control over the conventional proportional-integral control method. Simulation results are reported and proved to be in good agreement with the relevant experimental results
Acute lower respiratory tract infection due to respiratory syncytial virus in a group of Egyptian children under 5 years of age
<p>Abstract</p> <p>Background and aim</p> <p>Respiratory syncytial virus (RSV) is one of the most important causes of acute lower respiratory tract infections (ALRTI) in infants and young children. This study was conducted to describe the epidemiology of ALRTI associated with RSV among children ⤠5 years old in Egypt.</p> <p>Patients and Methods</p> <p>We enrolled 427 children ⤠5 years old diagnosed with ALRTI attending the outpatient clinic or Emergency Department (ED) of Children Hospital, Cairo University during a one- year period. Nasopharyngeal aspirates were obtained from the patients, kept on ice and processed within 2 hours of collection. Immunoflourescent assay (IFA) for RSV was performed.</p> <p>Results</p> <p>91 cases (21.3%) had viral etiology with RSV antigens detected in 70 cases (16.4%). The RSV positive cases were significantly younger than other non-RSV cases (mean age 8.2 months versus 14.2 months, p <0.001). RSV cases had significantly higher respiratory rate in the age group between 2-11 months (mean 58.4 versus 52.7/minute, p < 0.001) and no significant difference in the mean respiratory rate in the age group between 12-59 months. More RSV cases required supplemental oxygen (46% versus 23.5%, p < 0.001) with higher rate of hospitalization (37.1% versus 11.2%, p < 0.001) than the non-RSV cases. 97% of RSV cases occurred in winter season (p < 0.001).</p> <p>Conclusion</p> <p>RSV is the most common viral etiology of ALRTI in children below 5 years of age, especially in young infants below 6 months of age. It is more prevalent in winter and tends to cause severe infection.</p
Vitamin C attenuates the toxic effect of nutmeg on primary visual occipital cortex in rats
Background: Nutmeg is neurotoxic in rats and possibly neurotoxic also in hu- mans. The aim of this study is to investigate the effect of nutmeg on the primary visual occipital cortex of adult male rat and to evaluate the possible protective role of vitamin C.Â
Materials and methods: Fifty Sprague-Dawley adults male rats were randomly divided into three main groups; control, nutmeg-treated (500 and 1000 mg/kg/ /day) and protected groups (nutmeg + vitamin C [500 mg/kg/day]). All rats were treated orally by gavage for 5 days per week for 6 weeks. At the end of the experiment, primary visual occipital cerebral cortex was subjected to histological, immunohistochemical and genetic analyses.Â
Results: Our results revealed toxic effects of nutmeg on the primary visual occipital cerebral cortex in adult male albino rat. This was indicated by histopathological alterations, including pyknotic nuclei surrounded with vacuolations by light micro- scopic studies and degenerations of organelles by electron microscopic studies. In addition, we detected an increase in immunoreactivity for GFAP and caspase-3 by immunohistochemical assessments. Apoptotic bands appeared in genetic studies. Co-administration of vitamin C ameliorated nutmeg-induced toxic alterations on the primary visual occipital cerebral cortex.Â
Conclusions: Nutmeg administration caused histopathological and genetic changes in the primary visual occipital cerebral cortex in adult male albino rats. These changes were improved by co-administration of vitamin C.
Surgical Management of Chronic Suppurative Otitis Media: A 3-year Experience
Background/Objective: To determine the outcome of surgery for chronic
suppurative otitis media at our department over 3 years, between 2001
and 2003. The outcome measures were; achievement of dry ear, closure of
tympanic membrane perforation and improvement in hearing for patients
who had myringoplasty. Methods: A retrospective review of case notes of
patients with chronic suppurative otitis media (cholesteatoma and
non-cholesteatomatous disease) operated upon by 2 consultant ENT
surgeons in our department over a 3 year period. The operations
performed were mastoidectomy and type I tympanoplasty or myringoplasty.
The results were analysed and presented. Results: Seventy three
patients were operated upon for cholesteatoma and non-cholesteatomatous
chronic otitis media during this period, there were 41 males and 32
females with a sex ratio of 1:1.3. Age range was 9 to 84 years with the
mean age of 37 years. 17 of them were children aged 9 to 15 years
(24%). 25 patients (34.2%) had cholesteatoma and 48 (65.8%) had
non-cholesteatomatous disease 41 (56.2%) had myringoplasty and 29
(39.7%) had mastoidectomy, and 3 (4.1%) patients had
tympanomastoidectomy. 62.5% (n=20) mastoid cavities were dry at 12
months follow up. Perforation closure was achieved in 89% (n=34).
Binaural hearing was achieved in 6 patients and in 4 patients the
operated ear became the better hearing ear; air-bone gap was closed
completely in 8 patients (19.5%), and in 36.6% (n=15) the gap was
closed to within 10dB. There was no deterioration in hearing in the
operated ears. One patient presented with House Brachman grade 2 facial
palsy pre-operatively which worsened to grade 4 post operatively but
improved to pre-operative grade at 12month follow up. Conclusion:
Chronic suppurative otitis media is a disease that is still with us,
and at our department, the surgery has a high success rate, which is
also comparable in adults and children.Fond/Objectif: Pour d\ue9terminer les r\ue9sultats de la
chirurgie pour l'otite moyenne chronique suppurative \ue0 notre
d\ue9partement pendand une p\ue9riode de 3 ans, entre 2001 et 2003.
Les mesures de r\ue9sultats \ue9taient; accomplissement d'oreille
s\ue8che, fermeture de perforation de tympan secondaire et
am\ue9lioration d'audition pour les malades qui ont eu la
myringoplastie. M\ue9thodes : Un examen r\ue9trospectif des notes
de cas des malades pr\ue9sentant l'otite moyenne chronique
suppurative ( maladie cholest\ue9atome et non-cholest\ue9atome) qui
ont \ue9t\ue9 op\ue9r\ue9s par 2 chirurgiens consultants ORL
dans notre d\ue9partement pendant une p\ue9riode de 3 ans. Les
op\ue9rations \ue9taient la masto\uefdectomie et le type I de la
tympanoplastie ou de la myringoplastie. Les r\ue9sultats ont
\ue9t\ue9 analys\ue9s et pr\ue9sent\ue9s. R\ue9sultats:
Soixante-treize malades ont \ue9t\ue9 op\ue9r\ue9s pour l'otite
moyenne chronique cholest\ue9atome et non cholest\ue9atome pendant
cette p\ue9riode. Il y avait 41 m\ue2les et 32 femelles avec un sex
ratio de 1:1,3. La cha\ueene d'\ue2ge \ue9tait de 9 \ue0 84 ans
avec l'\ue2ge moyen de 37 ans. 17 d'entre eux \ue9taient des
enfants \ue2g\ue9s 9 \ue0 15 ans (24%). 25 malades (34,2%) ont eu
le cholest\ue9atome et 48 (65,8%) ont eu la maladie
non-cholest\ue9atome. 41 (56,2%) ont eu la myringoplastie et 29
(39,7%) ont eu la masto\uefdectomie, et 3 (4,1%) malades ont eu
tympanomasto\uefdectomie. 62,5% (n=20) cavit\ue9s du mastoide
\ue9taient s\ue8ches \ue0 12 mois continuent. La fermeture de
perforation a \ue9t\ue9 r\ue9alis\ue9e dans 89% (n=34).
L'audition binaurale \ue9tait accomplie dans 6 malades et dans 4
malades, l'oreille op\ue9r\ue9e est devenue l'oreille de meilleure
audition ; l'\ue9nergie r\ue9serve de l'oreille interne a
\ue9t\ue9 combl\ue9e compl\ue8tement dans 8 malades (19,5%), et
dans 36,6% (n=15) l'\ue9cart a \ue9t\ue9 r\ue9duit au sein de
10dB. Il n'y avait aucune d\ue9t\ue9rioration d'audition dans les
oreilles op\ue9r\ue9es. Un malade a \ue9t\ue9
pr\ue9sent\ue9 avec la paralysie du nerf facial de la
cat\ue9gorie 2 de la Chambre Brachman pr\ue9-perop\ue9ratoirement
qui a empir\ue9 \ue0 la cat\ue9gorie 4
post-perop\ue9ratoirement mais a am\ue9lior\ue9 \ue0 la
cat\ue9gorie pr\ue9-perop\ue9ratoire \ue0 12 mois
ult\ue9rieurs. Conclusion: L'otite moyenne chronique suppurative
est une maladie qui est toujours avec nous, et \ue0 notre
d\ue9partement, la chirurgie a un taux \ue9lev\ue9 de
succ\ue8s, qui est \ue9galement comparable dans les adultes et les
enfants
Effect of vitamin B17 on experimentally induced colon cancer in adult male albino rat
Background: Colon cancer is considered to be the third most common cancer worldwide. At diagnosis of colon cancer, 3.7â11% developed bone metastasis. Diet based strategies are important for prevention and treatment of colon cancer. This study investigated the effect of vitamin B17 on a DMH induced rat model of colon cancer.
Materials and methods: Eighty young adult male albino rats were divided into five groups: group I (control group), group II (vitamin B17), group III (colon cancer), group IV (protected) and group V (treated). Distal colon sections were prepared for light and scanning electron microscopic examination. Lumbar vertebrae specimens were prepared for light microscopic study. Morphometric and statistical analysis were done.
Results: In comparison with the control, both colon cancer and treated groups showed invasion of the colonic tissue by pleomorphic branching colonic glands of variable shapes and sizes lined with dysplastic elongated hyperchromatic nuclei with frequent mitotic figures or stratified multi-layered crowded nuclei with an extremely significant (p < 0.0001) reduction of goblet cell number when compared to the control together with major pathological bone changes were observed in colon cancer and the treated groups.
Conclusions: While the protected group showed impressive improvement of all previously mentioned diameters
MODIFIED DOUBLE-DISC SYNERGY TEST (MDDST) FOR DETECTION OF EXTENDED-SPECTRUM BETA-LACTAMASES IN AmpC BETA-LACTAMASE-PRODUCING KLEBSIELLA CLINICAL ISOLATES
The detection of ESBL(S) in gram-negative bacteria that produce AmpC beta-lactamases is problematic. In the present study, the performance of MDDST that employs a combination of cefepime and piperacillin-tazobactam for the detection of ESBL(S) Klebsiella producing AmpC beta-lactamases was evaluated and compared with DDST. E-test phenotypic confirmatory and MTDT tests were adopted for more data confidence. A total of 100 clinical isolates of Klebsiella, which met the CLSI (2012) screening criteria as having broth microdilution (BMD) MIC of > or =2 mg/mL for at least one extended spectrum cephalosporin [ceftazidime (CAZ), cefotaxime (CTX) and cefpodoxime], were accurately-selected for the study. MDDST detected ESBLs in 62 out of the100 studied isolates with 100% sensitivity and specificity, whereas DDST detected ESBLs in only 52 isolates with 92.9% sensitivity and 100% specificity. E-test could detect ESBLs in 62 isolates, while as many as 34/62 ESBL positive isolates were confirmed to be AmpC beta-lactamase positive by the MTDT. MDDST and E-Test could detect ESBLs in all the 34 AmpC positive isolates, whereas DDST detect ESBLs in only 26 isolates.The study recommended MDDST as superior to DDST for the detection of ESBLs in AmpC beta-lactamase-producing Klebsiella spp. and this was confirmed by MTDT and E-Tests
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