Reaction of 2,5-Disubstituted-1,3,4-oxadiazoles

Some 5-aryl-2-mercapto-1,3,4-oxadiazole (I) reacted with maleic anhydride, maleic acid and p-benzoquinone affording 2-(5-aryl- -1,3,4-oxadiazol-2-ylthio)succinic anhydrides (II), 2-(5-aryl-1,3,4- -oxadiazol-2-ylthio)succinic acids (III) and 2-(2,5 dihydroxyphenylthio)- 5-aryl-l,3,4-oxadiazoles (IV), respectively. Treatment of 2- methylthio-5-phenyl-l,3-oxadiazole (V) with amines gives 2-[(alkyl or aryl)-amino]-5-phenyl-l,3,4-oxadiazoles (VI). Compound VIe condensed with aromatic aldehydes to give 2-(4-cinnamoylanilino)- 5-phenyl-l,3,4-oxadiazoles (VII) which on bromination afforded the dibromo derivative VIlI and on treatment with hydroxylamine afforded 2-[4-(5-aryl-2-isoxazolin-3-yl)anilino]-5-phenyl-1,3,4-oxadiazoles (IX). Reacting VII with hydrazine hydrate gave 2-[4-(5-aryl-2-pyrazolin-3-yl)anilino]-5-phenyl-l,3,4-oxadiazoles (X), while on treatement VII with acetylacetone and ethylacetoacetate afforded 2- [4-(4-acetyl or carbethoxy-5-phenyl-l-cyclohexen -3-one- -1-yl)anilino]-5-phenyl-l,3,4-oxadiazoles (XIIa, b), respectively

High scrotal approach for secondary orchidopexy in cases of recurrent and iatrogenic undescended testes

Background/purpose Secondary orchidopexy is often difficult due to altered anatomy and dense scarring following previous operation. The aim of this study was to assess the feasibility and results of secondary transcrotal orchidopexy for the palpable recurrent and iatrogenic undescended testes.Patients and methods The case records of all children who underwent secondary orchidopexy through high scrotal incision during the study period May 2004 to April 2009 were retrospectively reviewed.Results Redo orchiopexy using the high scrotal approach was used to treat 41 testes during a 4-year period. Eight of these cases occurred after an inguinal hernia repair and 33 cases occurred after a previous orchiopexy. At follow-up, 39 of the 41 orchidopexies (95.2%) testes were found viable. Two testes (4.8%) were recorded to have atrophied.Conclusion This study shows that secondary orchidopexy through a high scrotal incision is a safe, effective, and applicable technique for recurrent and iatrogenic undescended testes.Keywords: high scrotal approach, redo orchidopexy, undescended testi

The properties of concrete sandwich beams with polystyrene concrete cores

Not availabl

First Principles Simulations of Boron Diffusion in Graphite

Boron strongly modifies electronic and diffusion properties of graphite. We report the first ab initio study of boron interaction with the point defects in graphite, which includes structures, thermodynamics, and diffusion. A number of possible diffusion mechanisms of boron in graphite are suggested. We conclude that boron diffuses in graphite by a kick-out mechanism. This mechanism explains the common activation energy, but large magnitude difference, for the rate of boron diffusion parallel and perpendicular to the basal plane. © 2007 The American Physical Society

Some Chemical Aspects of Tetrahydro-1-thiopyran-4-one Derivatives

3,5-Diarylmethylene-2,6-diphenyltetrahydrothiopyran-4-thiones, 2, reacted with two or four moles of bromine to form 3-aryimethylene 5-bromoarylmethylene- 2,6-dipheny1tetrahydrothiopyran- -4-thione, 3, and 3-arylmethylene-5-bromoarylmethylene-2,6-dibromo- 2,6-diphenyltetrahydrothiopyran-4-thione, 5, respectively. Compound 2a reacted with amines giving 2,6-diphenyl-5-iminophenylmethyl- 3-phenylmethylenetetrahydrothiopyran-4-thiones, 6. Diphenydiazomethane and 9-diazofluorene converted 2a into 4-diphenylethylene- 2,6-dipheny1-3,5 diphenylmethylenetetrahydrothiopyran, 7, and 2,6-diphenyl-3,5-diphenylmethylene-4-(9-fluorenylidene) tetrahydrothiopyran, 8, respectively. Compounds 2 with copper-bronze afforded 3,3\u27,5,5\u27-tetraarylmethylene-2,2\u27 ,6,6\u27-tetraphenyl-Lr-thio- 4,4\u27 dipyranylidenes

Platelet-Rich Fibrin Versus Connective Tissue Graft Using Vestibular Incision Subperiosteal Tunnel Access (VISTA) Technique in Multiple Gingival Recessions: Randomized Controlled Trial

Background: One of the most common esthetic concerns in dentistry is gingival recession (GR), and despite the various treatment strategies for root coverage, multiple recessions still present a great challenge, especially Miller Class III/RT2. Thus, this study aimed to compare the effect of platelet-rich fibrin (PRF) versus connective tissue graft (CTG) using vestibular incision subperiosteal tunnel access (VISTA) in patients with Miller class III/RT2 multiple recessions for root coverage. Methods: Twenty-eight patients with multiple Class III/RT2 gingival recessions were randomly allocated to two equal groups – group 1 (VISTA+PRF) and group 2 (VISTA+CTG). Recession depth (RD) and width (RW), probing depth (PD), clinical attachment level (CAL), gingival thickness, keratinized tissue width, and root coverage esthetic score (RES) were measured at 0, 3, and 6 months. Statistical analysis was performed using repeated measures analysis of variance (ANOVA). Bonferroni’s post-hoc test was used for pair-wise comparisons when ANOVA was significant. For non-parametric data, the Mann-Whitney U test was used to compare between the two groups. Results: Within each group, a significant difference from baseline to six months was found. However, between groups, the results for the VISTA+CTG group significantly surpassed the VISTA+PRF group in most clinical outcomes; gingival recession depth (0.5 [0.25-1.75] and 1.33 [0.75-2], respectively), and width (1 [0.38-3.75] and 2.33 [1.33-3], respectively), gingival thickness at three and six months (2.62±0.36 and 2.63±0.36, respectively) and (1.85±0.2 and 1.87±0.18, respectively), and keratinized tissue width (3.98±0.72 and 3.33±0.56, respectively). However, CAL and PD showed a statistically insignificant difference when comparing both groups. Conclusion: The use of CTG is superior to PRF in root coverage of Miller Class III/RT2 when the VISTA technique is used. Connective tissue grafts can be considered the gold standard for root coverage

Neutrophil-surface antigens CD11b and CD64 expression: a potential predictor of early-onset neonatal sepsis

Background: CD11b, an α subunit of the β2 integrin adhesion molecule, and CD64, the high affinity Fcγ receptor I, are specific neutrophil-surface antigens activated in response to systemic inflammation and, hence, they might potentially help identifying neonatal infections. Objective: We sought to evaluate the time course of expression and diagnostic and prognostic utility of CD11b and CD64 in early-onset sepsis in the suspected newborn. Methods: Sixty newborn infants (28-40 weeks gestation) with antenatal risk factors for sepsis were enrolled and subjected to sepsis work-up including complete blood count, quantification of serum C reactive protein (CRP) and flow cytometric analysis of CD11b and CD64 in cord blood (0 h). These tests were repeated at 8, 24 and 48 h postnatally. Neonates were defined, retrospectively, in two groups: sepsis and no infection, on basis of clinical observation over their first five postnatal days and sepsis work-up results. Results: A significant enhancement of neutrophil CD11b and CD64 expression was demonstrated in the sepsis group as compared to the non-infected group. CD11b over-expression had an onset at 0 h. Its mean value approached two-fold mean level of non-infected neonates by 8-24 h, and declined thereafter. CD64 rising onset was detectable at 8 h and its mean percentage reached four-fold mean value of the non-infected group at 24 h. At 24 h, an optimal cut-off value for CD11b expression of 35% (sensitivity 80%, and specificity 100%), and for CD64 expression of 17% (sensitivity 88%, and specificity 90.3%) had the best performance for prediction of sepsis. Combined use of both markers at 24 h yielded 90% sensitivity and 95% specificity for sepsis prediction. Sepsis survivors showed significantly lower mean expression for CD11b and CD64 as compared to those with fatal outcome. At 24 h, a cut-off value of 88% expression for CD11b and 50% expression for CD64 predicted mortality with sensitivity and specificity of 100%. Conclusion: Enhanced expression of neutrophil-surface antigens CD11b and CD64 could be a promising tool for prediction and therapeutic decision-making in early-onset sepsis indicating the necessity of initiation of antimicrobial therapy and reduction of its unnecessary use in non-infected neonates even before definitive microbiologic identification.Keywords: sepsis, neonate, early-onset, neutrophil activation, surface antigen, CD11b, CD64Egypt J Pediatr Allergy Immunol 2004; 2(2): 90-10

Investigations on Recycling Methods of Gypsum Plaster Waste (Review)‎

يحتاج الإنسان إلى الحفاظ على البيئة التي يعيش فيها من أجل أن تبقى مناسبة للحياة للأجيال القادمة. حيث تتسبب الصناعات المختلفة التي يشكلها الإنسان في تلوث البيئة من خلال الطمر بالمخلفات التي تنتج عنها وتتسبب في استهلاك مواد أولية جديدة. من هذه الصناعات، صناعة البورك. حيث يتم إنتاج كمية كبيرة من مخلفات البورك من مجالات مختلفة يتم فيها استخدام البورك. لذلك من الضروري العمل على الحد من هذه النفايات عن طريق إعادة استخدامها أو إعادة تدويرها بأقل التكاليف والإجراءات. تهدف هذه الدراسة إلى مراجعة الطرق المستخدمة لتقليل كمية مخلفات البورك ومعرفة أفضلها. يمكن الاستنتاج أن أفضل الطرق لتقليل كمية مخلفات البورك بإعادة تدويرها بأقل التكاليف أو إعادة استخدامها بدون أي إجراءات مضافة.Humans need to keep on the clean environment in order to refine suitable life for the next generators. Where, the different industries formed by human, cause the environmental pollution by landfill with wastes produced from it and cause the consumption of fresh raw materials. One of these industries, is gypsum plaster industry. Where, a large amount of gypsum plaster waste is produced from different fields that use the gypsum plaster. Therefore, it is necessary to work on reduction of these wastes by reusing or recycling them with the least costs and procedures. This study aims to review the ways used to reduce gypsum waste amount and to figure ant the best among them. It can be concluded that the best ways to reduce the gypsum waste amount are by recycling it with the least costs or reusing it without any additional procedures