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In this work, seven copolymers possessing thienothiophene and mesitylboron units were prepared. Incorporation of triphenylamine (TPA) and tetraphenylethene (TPE) into TT unit was probed to enhance their light-emitting efficiencies. Density functional theory investigations of the model compounds revealed the presence of an intramolecular charge transfer transition between the donor TT units and the boron acceptor atom. Among the seven TT-boron copolymers, four of them were used for the fabrication of polymer light emitting diodes 9PLEDs) and two of the devices exhibited pure white color according to the CIE. Although the efficiencies of the devices are low, as this study is the first example of thienothiophene inverted perpendicular inverted perpendicular-boron copolymers emitting white color, they are promising examples for future studies.

The effect of thickness and alkoxy side chains on the optical properties of poly(p-phenyleneethynylene)alt-poly(p-phenylenevinylene)s (PPE-PPVs) have been investigated in parallel fashion. A Forster energy transfer mechanism has been invoked in order to infer the exciton diffusion length (L-D). The latter parameter has been determined for six differently alkoxy-substituted PPE-PPVs for different thicknesses. The dependence of L-D upon the donor-acceptor (D-A) distance (d) has been assessed as well. The results reveal an increase of L-D up to 25 nm, with the increase of the sample thickness and side chain length. (C) 2017 Elsevier B.V. All rights reserved.

Objective: In this experiment, supplementation of the diet with increased levels of glutamine was used to determine glutamine enriched diet effect on the healing of ileal anastomosis.Methods: Forty albino Wistar rats, in four groups, had a special diet 7 days prior to surgery and 7 days after surgery. On the 7th day of study a complete cut of the ileal wall was carried out and an anastomosis was performed using single layer interrupted inverting sutures. Group 1 received a normal diet for all 14 days; group 2 received a glutamine enriched diet 7 days prior to surgery and a normal diet 7 days after surgery; group 3 received a normal diet prior to surgery and a glutamine enriched diet after surgery; group 4 received a constant glutamine enriched diet. On the 7th postoperative day, tensile strength measurements and hydroxyproline level analyses were done.Results: A preoperative glutamine enriched diet did not show any significant improvement in the bursting pressure and hydroxyproline levels on the 7th postoperative day, but pre and postoperative, and postoperative glutamine enriched diet significantly improved when compared with the normal diet group (p

Two novel D-A (donor-acceptor) and one D-A-D small molecules containing mesitylborane as an acceptor and triphenylamine as a donor, linked through a thieno[3,2-b]thiophene p-conjugated spacer, are synthesized and characterized. Their photo- and electrochemical properties were investigated by experimental and computational studies. The emission quantum efficiencies were determined to be between 46% and 68% in THF. Their solid-state quantum yields were recorded up to 42%. The fabricated electroluminescent devices as emitting materials showed sky-blue to yellowish green emissions. Their devices exhibit high performance with a turn-on voltage, maximal brightness, and highest luminescence efficiency of up to 4.0 V, 1200 cd m(-2) and 1.13 cd A(-1), respectively. These results pave new avenues for the future molecules possessing D and A units connected via fused thiophenes.

Background: There is a lack of specificity of the analgesic agents used to treat headache and underlying acute carbon monoxide poisoning. Objective: To compare effectiveness of "oxygen alone" vs "metoclopramide plus oxygen" vs "metamizole plus oxygen" therapy in treating carbon monoxide-induced headache. Design: A prospective, multicenter, double-blind, controlled trial. Setting: Three emergency departments in Turkey. Population: Adult carbon monoxide poisoning patients with headache. Methods: A total of 117 carbon monoxide-intoxicated patients with headache were randomized into 3 groups and assessed at baseline, 30 minutes, 90 minutes, and 4 hours. Main Outcome Measure: The primary outcomewas patient-reported improvement rates for headache. Secondary end points included nausea, need for rescue medication during treatment, and reduction in carboxyhemoglobin levels. Results: During observation, there was no statistical difference between drug type and visual analog scale score change at 30 minutes, 90 minutes, or 4 hours, for either headache or nausea. No rescue medication was needed during the study period. The reduction in carboxyhemoglobin levels did not differ among the 3 groups. Conclusion: The use of "oxygen alone" is as efficacious as "oxygen plus metoclopramide" or "oxygen plus metamizole sodium" in the treatment of carbon monoxide-induced headache. (C) 2016 Elsevier Inc. All rights reserved.

We carried out united-atom molecular dynamics simulations to understand the structural properties of peptide amphiphile (PA)-based cylindrical nanofibers and the factors that play a role in the "Self-Assembly" process on some specific nanofibers. In our simulations, we start from various cylindrical nanofiber structures with a different number of layers and a different number of PAs in each layer, based on previous experimental and theoretical results. We find that the 19-layered nanofiber, with 12 PAs at each layer, distributed radially and uniformly with alkyl chains in the center, is the most stable configuration with a diameter of 8.4 nm which is consistent with experimental results. The most dominant secondary structures formed in the fibers are random coils and beta-sheets, respectively. We also find that hydrophobic interactions between the VVAG-VVAG moiety of the PA molecules and electrostatic interactions between D-Na+ and between E-R are responsible for the fiber's self-assembly properties. During the aggregation process, first dimers, then trimers are formed.

We report on an example of odd even effect in self-assembled peptide amphiphiles (PAs) forming a cylindrical nanofiber. Minimum energy of the nanofiber depends on whether there are odd or even number of layers and whether each layer has odd or even number of PAs. More specifically, minimum energy for a nanofiber built of odd number of layers is achieved if each layer has even number of PAs uniformly, and radially aligned with alkyl chains in the center. On the other hand if the number of layers is even, energy is minimized if each layer has an odd number of PAs. (C) 2014 Elsevier B.V. All rights reserved.

Risk and Reliability in Geotechnical Engineering

Purpose: To investigate the efficacy and safety of neoadjuvant chemotherapy with docetaxel plus epirubicin with granulocyte colony-stimulating factor (G-CSF) support in locally advanced breast cancer patients.

Seroma formation is the most common complication after mastectomy and continues to be an important problem during the early postoperative period. Several surgical and medical methods have been developed to try to overcome this problem; however, so far none have been used successfully in the routine clinical practice. The aim of this study is to evaluate the effects of Corynebacterium parvum (CP) as a sclerosing agent in both prevention and treatment of seromas after mastectomy and axillary dissection in an animal model. Sixty female Sprague-Dawley rats underwent mastectomy and axillary dissection under general anaesthesia. Following surgery, the rats were treated in 1 of 3 ways. In the prevention group, 1 cm(3) (0.35 mg) CP solution was injected beneath the skin flap just before closure of the incision after mastectomy. In the treatment group, animals in which a seroma was formed, the fluid was aspirated, and 1 cm(3) CP solution was injected beneath the flap. In the control group, animals in which seromas formed, aspiration only was performed. The frequency of seroma for mation decreased when CP solution was injected immediately after the operation (p < 0.01). In addition, seroma formation was effectively treated by CP injection when compared with the control group (p < 0.05). CP was effective as a prophylactic agent in the prevention group and as a therapeutic agent in the treatment group in this experimental model. CP injection may be useful for the management of this problem in a clinical setting. Copyright (C) 2001 S. Karger AG, Basel.

Modern ooids from the Cleopatra Beach on Island in the Gokova Bay, South Aegean Sea, resemble ooids formed on the Bahamian platform. The concentric coatings of the ooids consist of two or more laminae around a carbonate-or non-carbonate nucleus. The oolite cortex is transparent, whereas the non-transparent portions seem to be the dark fields on the oolitic surfaces. The ooids are mixed with molluscan skeletal debris displaying micritic envelopes. Weakly consolidated ooids have been cemented by calcite in the form of meniscus cement.

Background: Phyllodes tumor (PT) is a rare neoplasm comprising less than 1 % of all breast tumors. Its clinical spectrum ranges from a benign and locally recurrent form of behavior to malignant and metastatic forms. The aim of the study was to evaluate the clinical characteristics, treatment regimens, survival and late complications in patients with PT.

The structural, vibrational and electronic properties of warfarin sodium, warfarin and its metabolites have been investigated theoretically by performing the molecular mechanics (MM+ force field), the semi-empirical self-consistent-field molecular-orbital (AM1), and density functional theory calculations. The geometry of the molecules have been optimized, the vibrational dynamics and the electronic properties of the molecules have been calculated in their ground state in gas phase.

Objective: Examination of predictive factors healthy lifestyle behaviours and compare coping styles with stress of adolescents with and without Hearing Loss (HL). Methods: A comparative cross-sectional design was employed. The participants comprise high school students with (n= 272) and without (n= 272) HL. Participants completed questionnaires on coping styles with stress and Adolescent Lifestyle Profile Scale 2 (ALP-R2). Descriptive statistics, chi-square, t-test, and multiple linear regression analysis were used to analyze the responses given to the above instruments. Results: Adolescents without HL (116.46 +/- 16.89) had significantly higher scores on the lifestyle profile scale than another group (113.68 +/- 16.12) (p

Recognition of molecules and regulation of extracellular matrix synthesis are some of the functions of enzymes in addition to their catalytic activity. While a diverse array of enzyme-like materials have been developed, these efforts have largely been confined to the imitation of the chemical structure and catalytic activity of the enzymes, and it is unclear whether enzyme-mimetic molecules can also be used to replicate the matrix-regulatory roles ordinarily performed by natural enzymes. Self-assembled peptide nanofibers can provide multifunctional enzyme-mimetic properties, as the active sequences of the target enzymes can be directly incorporated into the peptides. Here, we report enhanced bone regeneration efficiency through peptide nanofibers carrying both catalytic and matrix-regulatory functions of alkaline phosphatase, a versatile enzyme that plays a critical role in bone formation by regulating phosphate homeostasis and calcifiable bone matrix formation. Histidine presenting peptide nanostructures were developed to function as phosphatases. These molecules are able to catalyze phosphate hydrolysis and serve as bone-like nodule inducing scaffolds. Alkaline phosphatase-like peptide nanofibers enabled osteogenesis for both osteoblast-like and mesenchymal cell lines.

Cataloged from PDF version of article. Amyloid peptides are important components in many degenerative diseases as well as in maintaining cellular metabolism. Their unique stable structure provides new insights in developing new materials. Designing bioinspired selfassembling peptides is essential to generate new forms of hierarchical nanostructures. Here we present oppositely charged amyloid inspired peptides (AIPs), which rapidly self-assemble into nanofibers at pH 7 upon mixing in water caused by noncovalent interactions. Mechanical properties of the gels formed by selfassembled AIP nanofibers were analyzed with oscillatory rheology. AIP gels exhibited strong mechanical characteristics superior to gels formed by self-assembly of previously reported synthetic short peptides. Rheological studies of gels composed of oppositely charged mixed AIP molecules (AIP-1 + 2) revealed superior mechanical stability compared to individual peptide networks (AIP-1 and AIP-2) formed by neutralization of net charges through pH change. Adhesion and elasticity properties of AIP mixed nanofibers and charge neutralized AIP-1, AIP-2 nanofibers were analyzed by high resolution force− distance mapping using atomic force microscopy (AFM). Nanomechanical characterization of self-assembled AIP-1 + 2, AIP-1, and AIP-2 nanofibers also confirmed macroscopic rheology results, and mechanical stability of AIP mixed nanofibers was higher compared to individual AIP-1 and AIP-2 nanofibers self-assembled at acidic and basic pH, respectively. Experimental results were supported with molecular dynamics simulations by considering potential noncovalent interactions between the amino acid residues and possible aggregate forms. In addition, HUVEC cells were cultured on AIP mixed nanofibers at pH 7 and biocompatibility and collagen mimetic scaffold properties of the nanofibrous system were observed. Encapsulation of a zwitterionic dye (rhodamine B) within AIP nanofiber network was accomplished at physiological conditions to demonstrate that this network can be utilized for inclusion of soluble factors as a scaffold for cell culture studies. Copyright © 2012 American Chemical Society

Bu çalışma II. Int. Congress of C.I.A.N.S. 1975 Prague kongresinde tebliğ edilmiştir. Bu çalışmada, son zamanlarda geniş bir kullanım sahası bulan Nobrium'un 100 mg/ kg/24 saat lik dozunun sıçanların karaciğer ve böbrekleri üzerindeki toksik etkisi araştırılmıştır. Bu amaçla ağırlıkları 170-230 gr. arasında değişen 60 adet wistar tipi beyaz sıçan kullanılmıştır. Hayvanlar test ve kontrol grubu olarak ikiye ayrılmış olup böbrekler için, histopatolojik muayene yanında maksimal renal konsantrasyon kapasitesi, glomerüler filtrasyon oranı ile serum kreatinin seviyesi ve akciğerler için de yine histopatolojik muayene yanında serum total proteini, serum protein elektroforezi ve serum transaminazları kriter olarak kullanılmıştır. Deneyimlerimizin sonuçlarına göre, çanlara 30 gün süreyle 100 mg/kg/ 24 saat Nobrium uygulanması bu hayvanların karaciğer ve böbreklerinde gerek morfolojik ve gerekse araştırılan fonksiyon testlerinde anlamlı bir değişikliğe sebep olmamıştır. We searched the side effects of Nobrium (1 00 mg/ kg/ 24h.) on kidneys and livers of rats. 60 white wistar rats weighing between 170-230 gr. were used for this research. Animals were divided in two groups were the first was the test group . The following parameters were used to evaluate the changes in kidneys and livers: Maximal renal concentrating ability, glomerular filtration rate,serum creatinin level, total blood proteins, serum protein electrophoresis, serum transaminases and histopathological examinations. According to the results of our experiments 100 mg/ kg/24h of Nobrium,for 30 days, has not any significant effect on livers and kidneys of rats in morphological examinations and functional tests.