306 research outputs found

    Development of Control Setup for a Material Testing Machine and Experimental Analysis of the Effect of Void Volume Fraction on the Strength of Recycled High-Density Polyethylene Material

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    This study is part of a larger research effort to investigate the mechanical response of composite beams to cyclic loading caused by waves striking beams imbedded in a low-cost sea wall. In the course of the research, it has been determined that material characterization of the beams is needed, and toward this end an MTS (Materials Test Systems) testing machine has been purchased by the TAMU Ocean Engineering Department. The testing machine was used for the purpose of testing recycled high-density polyethylene glass fiber composite specimens in order to characterize the stress-strain response and to measure the effect of void volume fraction (VVF) within the high-density polyethylene beams. Samples taken from different areas of the beams with varying VVF were tested and the effect of these voids was investigated for the purpose of determining the efficacy of deploying these structural components within low-cost sea walls. The study includes developing testing protocols, calibrating, and proof testing the machine in order to perform the experiments. Since the lab’s testing machine does not have a controller, a control setup is developed herein to control the MTS Testing Machine with signal processing via a National Instrument USB-6346 Data Acquisition Device and LabVIEW software. Results display the decrease in the stiffness as the VVF increases as well as decreases in the ultimate stress and ultimate strain. Increasing strain rates displayed higher stiffness, ultimate stress, and ultimate strain values. The results are discussed and invalid tests are described in detail wherein large voids locally misrepresent the general behavior and are incongruent with the valid tests

    Investigation of the Relationship between Sagittal Skeletal Nasal Profile Morphology and Malocclusions: A Lateral Cephalometric Film Study

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    The aim of this study was to evaluate the relationship between skeletal sagittal nasal profile morphology and sagittal skeletal malocclusions. Regarding lateral cephalometric films, the study was conducted in a total of 135 individuals without any prior orthodontic treatment (mean age of 17.91 +/- 1.91), including 49 males (mean age 17.91 +/- 1.16) and 86 females (mean age 17.78 +/- 1.91 years). The groups were divided into two groups as male and female according to gender, and three groups as skeletal Class 1, Class 2, and Class 3 according to the Steiner's ANB angle. In addition, skeletal groups were compared within groups by dividing into two groups of male and female. A total of eight parameters, three skeletal sagittal angular (SNA, SNB, and ANB angles), four nasal linear (R-A, N-A, N-ANS, and N-R distances) and one nasal angular (N1-N2/N2-R angle), were measured on each cephalometric film. The arithmetic mean and standard deviation of all measured nasal parameters were calculated. For statistical analysis, independent sample t-test and one-way analysis of variance (One-Way ANOVA) were used for normally distributed data, and Mann Whitney U and Kruskal Wallis tests were used for data that did not show normal distribution. For statistical analysis, p 0.05). R-A and N-A linear nasal parameters showed statistically significant differences between male and female sex groups in all skeletal malocclusion classes (p < 0.05). At first, results showed that males had longer measurements than females in all linear nasal parameters. Second, longer measurements were found in all linear nasal parameters in skeletal Class 3 individuals than those in skeletal Class 1 and Class 2 individuals. Third, the nasal bone concavity angle was greater in skeletal Class 2 individuals than the others

    Nutritional Changes of Sour Cherry (Prunus cerasus) Kernel Subjected to Aspergillus niger Solid-state Fermentation

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    This study was carried out to investigate the effects of Aspergillus niger solid-state fermentation on main nutritional content of cherry (Prunus cerasus) kernel. Three Aspergillus niger strains (ATCC 52172, ATCC 200345, ATCC 9142) were used in this study. Cherry kernels were analyzed for crude protein (CP), total ash (TA), total fat (TF), crude fiber (CF), nitrogen free extract (NFE), neutral detergent fiber (NDF) and acid detergent fiber (ADF) before and after fermentation to see nutritional change. CP level of the sour cherry increased by 14.1% and reached up to 41.66% from 27.56%. Fungal fermentation changed also TA, TF, CF, NFE, NDF, ADF contents of cherry kernel. These results suggest that solid-state fermentation with Aspergillus niger can be used for utilization nutritional properties of cherry kernels to make having potential in animal nutrition

    TÜKETİCİ GÜVEN ENDEKSİ İLE SEÇİM SONUÇLARI ARASINDAKİ İLİŞKİ: AK PARTİ VE CHP ÜZERİNE EKONOMETRİK BİR ANALİZ

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    Güven kavramıyla hayatın her alanında karşılaşılmaktadır. Evde, okulda, alışverişte, hatta gündelik ilişkilerimizde bile vazgeçilmez bir kavram olarak hayatımızla iç içedir. Güvenmediğimiz bir ürünü satın almayız, güvenmediğimiz bir bilgiyi kabul etmeyiz ya da güvenmediğimiz kişilerle samimi ilişkiler kurmayız. Dolayısıyla her alanda gördüğümüz bu kavramı siyaset alanında da görmek mümkündür. Nitekim bu kavram siyasetin en çok ilgilendiği konulardan biridir. Siyasete ve siyasetçilere bu anlamda duyulan bir güvensizlik günümüz rejimlerinde sıklıkla karşımıza çıkmaktadır. Bu bağlamda araştırma şirketlerinin yapmış olduğu güven ölçen anketlerde siyasetçilerin ve siyasal kurumların son sıralarda yer alması, siyasetin güven kavramına eğilmesine ön ayak olmuştur. Bu bağlamda oldukça etkili olan güven kavramın ölçülmesi bizi tüketici güven endeksi (TGE) kavramına yönlendirmektedir. Çalışmada 2004-2019 yılları arasında tüketici güven endeksi ile oy oranları arasındaki ilişkinin panel veri analizi ile araştırılması amaçlanmıştır. Dolayısıyla bu çalışmada siyasal partilerin özellikle iktidarda olan partinin, seçim dönemlerinde anket yaptırmak yerine tüketici güven endeksini baz alarak her ay seçim sonuçlarını tahmin etme imkanına sahip olması amacıyla hazırlanmıştır. Burada esasen tüketici güven endeksi ve partilerin oy oranları arasında ilişkinin tespit edilmesi amaçlanmıştır. Özellikle hipotezin doğruluğunun kanıtlanması amacıyla yapılan panel veri analizi sayesinde veriler arasındaki bağlantı kanıtlanarak çalışma özgünlüğünü ortaya koyacaktır. Yapılan analiz sonucunda Cumhuriyet Halk Partisi’nin aldığı oy oranlarıyla tüketici güven endeksi arasında bir ilişki tespit edilemezken, Adalet ve Kalkınma Partisi’nin aldığı oy oranı ile tüketici güven endeksi arasında istatistiksel olarak anlamlı ve pozitif yönlü bir ilişki tespit edilmiştir

    Evaluation of the Corrosion Resistance of Different Types of Orthodontic Fixed Retention Appliances: A Preliminary Laboratory Study

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    (i) Objective: The present study aimed to compare the electrochemical corrosion resistance of six different types of fixed lingual retainer wires used as fixed retention appliances in an in vitro study. (ii) Methods: In the study, two different Ringer solutions, with pH 7 and pH 3.5, were used. Six groups were formed with five retainer wires in each group. In addition, 3-braided stainless steel, 6-braided stainless steel, Titanium Grade 1, Titanium Grade 5, Gold, and Dead Soft retainer wires were used. The corrosion current density (i(corr)), corrosion rate (CR), and polarization resistance (R-p) were determined from the Tafel polarization curves. (iii) Results: The corrosion current density of the Gold retainer group was statistically higher than the other retainer groups in both solutions (p < 0.05). The corrosion rate of the Dead Soft retainer group was statistically higher than the other retainer groups in both solutions (p < 0.05). The polarization resistance of the Titanium Grade 5 retainer group was statistically higher than the other retainer groups in both solutions (p < 0.05). As a result of Scanning Electron Microscope (SEM) images, pitting corrosion was not observed in the Titanium Grade 1, Titanium Grade 5 and Gold retainer groups, while pitting corrosion was observed in the other groups. (iv) Conclusion: From a corrosion perspective, although the study needs to be evaluated in vivo, the Titanium Grade 5 retainer group included is in this in vitro study may be more suitable for clinical use due to its high electrochemical corrosion resistance and the lack of pitting corrosion observed in the SEM images

    Evaluation of the Demineralization Development around Different Types of Orthodontic Brackets

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    The aim of this study was to compare the demineralizations of the enamel surfaces around different types of orthodontic brackets in an artificial cariogenic environment. A total of 90 extracted human maxillary first premolar teeth were used in this in vitro study. The teeth were divided into 6 groups, 5 study and 1 control, each consisting of 15 samples. Victory metal, Gemini metal, Clarity self-ligating ceramic, APC Clarity Advanced ceramic and Clarity Advanced ceramic brackets (3M Unitek, Monrovia, Calif) used in the study groups were bonded to the teeth with the direct technique. The gingival, occlusal and proximal enamel surfaces adjacent to the brackets were measured with a DIAGNOdent pen (KaVo, Biberach, Germany) (T0). Then, the teeth were placed in a cariogenic suspension environment containing Streptococcus mutans, sucrose and artificial saliva. The teeth were removed from the cariogenic suspension at the end of 28 days. Enamel surfaces were remeasured with DIAGNOdent and the values were recorded (T1). Whether the obtained data were homogeneously distributed or not was determined by the Kolmogorov-Smirnov test, within-group comparisons were performed with the Wilcoxon test, and between-group comparisons were performed with Mann-Whitney U and Kruskal-Wallis tests. Significance level was accepted as p < 0.05. In all groups, the demineralization values of the enamel surfaces in the gingival, proximal and occlusal surfaces adjacent to the brackets were significantly higher in the T1 period than in the T0 period (p < 0.05). In the T1 period of Gemini metal, Clarity self-ligating ceramic and Clarity advanced ceramic bracket groups, the demineralization values of the proximal enamel surfaces were found to be significantly higher than the Victory metal and APC Clarity Advanced ceramic bracket groups (p < 0.05). In the T1 period, the demineralization values of the occlusal enamel surfaces of the Victory metal, APC Clarity Advanced ceramic bracket groups and control group were significantly lower than the Gemini metal, Clarity self-ligating ceramic and Clarity Advanced ceramic bracket groups (p < 0.05). Significant increases in enamel demineralization values were observed as a consequence of increased retention areas for microbial dental plaque on enamel surfaces adjacent to the bracket. Considering the importance of minimizing enamel demineralization in fixed orthodontic treatments, less enamel demineralization in Victory metal and APC Clarity Advanced ceramic bracket groups showed that these brackets can be preferred in patients with poor oral hygiene

    Chemical glycosylations for the synthesis of building units of post-translational modifications

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    In chemical glycosylation reactions, a glycosyl donor couples with a glycosyl acceptor through glycosidic linkage. Most of the products end up with a mixture due to the formation of a stereogenic center at the anomeric carbon. Activation with a suitable Lewis acid and introduction of the non‐participating protecting group on donor and acceptor results in a selective product. Herein, we used a suitably protected donor and acceptor which produced an orthogonally protected building block with α‐selectivity. We used also a donor for the synthesis of modified phosphoribosylated amino acid. The formation of glycoside products can be used to synthesize complex biologically important organic molecules

    Emerging concepts about NAIP/NLIRC4 inflammasomes

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    Neuronal apoptosis inhibitory protein (NAIP)/NOD-like receptor (NLR) containing a caspase activating and recruitment domain (CARD) 4 (NLRC4) inflammasome complexes are activated in response to proteins from virulent bacteria that reach the cell cytosol. Specific NAIP proteins bind to the agonists and then physically associate with NLRC4 to form an inflammasome complex able to recruit and activate pro-caspase-1. NAIP5 and NAIP6 sense flagellin, component of flagella from motile bacteria, whereas NAIP1 and NAIP2 detect needle and rod components from bacterial type III secretion systems, respectively. Active caspase-1 mediates the maturation and secretion of the pro-inflammatory cytokines, 11,113 and 11,18, and is responsible for the induction of pyroptosis, a pro-inflammatory form of cell death. in addition to these well-known effector mechanisms, novel roles have been described for NAIP/NLRC4 inflammasomes, such as phagosomal maturation, activation of inducible nitric oxide synthase, regulation of autophagy, secretion of inflammatory mediators, antibody production, activation of T cells, among others. These effector mechanisms mediated by NAIP/NLRC4 inflammasomes have been extensively studied in the context of resistance of infections and the potential of their agonists has been exploited in therapeutic strategies to non-infectious pathologies, such as tumor protection. Thus, this review will discuss current knowledge about the activation of NAIP/NLRC4 inflammasomes and their effector mechanisms.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)INCTVUniversidade Federal de São Paulo, Ctr Terapia Celulare & Mol CTC Mol, BR-04044010 São Paulo, SP, BrazilUniversidade Federal de São Paulo, Dept Ciencias Biol, BR-04044010 São Paulo, SP, BrazilUniversidade Federal de São Paulo, Ctr Terapia Celulare & Mol CTC Mol, BR-04044010 São Paulo, SP, BrazilUniversidade Federal de São Paulo, Dept Ciencias Biol, BR-04044010 São Paulo, SP, BrazilFAPESP: 2013/16010-5Web of Scienc
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