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This work contributes to the understanding of damage of adhesive layers generated during the manufacturing process and its effect on the subsequent load carrying capacity of the joint. A temperature dependent cohesive zone model is used to predict damage during the manufacturing process. Therefore, parameters for a temperature-dependent as well as a strain rate-dependent model were determined on various specimens. It is shown, that it is possible to predict the manufacturing induced damage within the adhesive layer with sufficient accuracy using a cohesive zone model. Furthermore, a continuous process chain for numerical simulations is developed, which allows to determine the adhesive layer damage by means of a process simulation and to consider the changed mechanical properties in a subsequent crash simulation. To simplify the procedure, a software tool is presented that automatically performs the described steps. The developed method is applied to a car body simulation to investigate the effects caused by the manufacturing process. [ABSTRACT FROM AUTHOR]

In 2017 and 2018 GFZ performed two gravimetry campaigns on commercial ferries in the Baltic Sea. The nature of such "non-dedicated" campaigns is different from "dedicated" campaigns that are performed on research vessels with tracks planned according to gravity measurement needs. The non-dedicated campaigns use non-survey vessels or survey vessels running for other purposes such as hydrographic measurements, which may require additional corrections. To assess the usefulness of non-dedicated campaigns, we analysed gravity measurements collected on two commercial ferries as part of the EU funded FAMOS project. Besides the typical marine gravimetry corrections, we also investigated the corrections for the vertical accelerations due to the ship's movement and the dynamical effect due to the cross-coupling between horizontal and vertical acceleration components. Taking the latter two corrections into account partly leads to slight improvements, but our results also demonstrate that the standard processing without the two corrections, as used in most of the dedicated campaigns, already delivers good quality end products that fulfil the requirements of a typical marine gravimetry survey with an uncertainty of about 1 mGal. Our findings suggest that gravimetry campaigns on commercial ferries can be used to complement dedicated marine gravimetry campaigns and contribute to geodetic purposes. [ABSTRACT FROM AUTHOR]

During the last few years, the determination of high-resolution global gravity field has gained momentum due to high-accuracy satellite-derived observations and development of forward gravity modelling. Forward modelling computes the global gravitational field from mass distribution sources instead of actual gravity measurements and helps improving and complementing the medium to high-frequency components of the global gravity field models. In this study, we approximate the global gravity potential of the Earth's upper crust based on ellipsoidal approximation and a mass layer concept. Such an approach has an advantage of spectral methods and also avoids possible instabilities due to the use of a sequence of thin ellipsoidal shells. Lateral density within these volumetric shells bounded by confocal lower and upper shell ellipsoids is used in the computation of the ellipsoidal harmonic coefficients which are then transformed into spherical harmonic coefficients on the Earth's surface in the final step. The main outcome of this research is a spectral representation of the gravitatioal potential of the Earth's upper crust, computed up to degree and order 3660 in terms of spherical harmonic coefficients (ROLI_EllApprox_SphN_3660). We evaluate our methodology by comparing this model with other similar forward models in the literature which show sub-cm agreement in terms of geoid undulations. Finally, EIGEN-6C4 is augmented by ROLI_EllApprox_SphN_3660 and the gravity field functionals computed from the expanded model which has about 5 km half-wavelength spatial resolution are compared w.r.t. ground-truth data in different regions worldwide. Our investigations show that the contribution of the topographic model increases the agreement up to ~ 20% in the gravity value comparisons. [ABSTRACT FROM AUTHOR]

The International Centre for Global Earth Models (ICGEM, http://icgem.gfz-potsdam.de/ , last access: 6 May 2019) hosted at the GFZ German Research Centre for Geosciences (GFZ) is one of the five services coordinated by the International Gravity Field Service (IGFS) of the International Association of Geodesy (IAG). The goal of the ICGEM service is to provide the scientific community with a state-of-the-art archive of static and temporal global gravity field models of the Earth, and develop and operate interactive calculation and visualization services of gravity field functionals on user-defined grids or at a list of particular points via its website. ICGEM offers the largest collection of global gravity field models, including those from the 1960s to the 1990s, as well as the most recent ones, which have been developed using data from dedicated satellite gravity missions, CHAMP, GRACE, GOCE, advanced processing methodologies, and additional data sources such as satellite altimetry and terrestrial gravity. The global gravity field models have been collected from different institutions at international level and after a validation process made publicly available in a standardized format with DOI numbers assigned through GFZ Data Services. The development and maintenance of such a unique platform is crucial for the scientific community in geodesy, geophysics, oceanography, and climate research. In this article, we present the development history and future plans of ICGEM and its current products and essential services. We present the ICGEM's data by means of Earth's static, temporal, and topographic gravity field models as well as the gravity field models of other celestial bodies together with examples produced by the ICGEM's calculation and 3-D visualization services and give an insight into how the ICGEM service can additionally contribute to the needs of research and society. [ABSTRACT FROM AUTHOR]

The present study was undertaken to investigate the individual and combined antioxidant or prooxidant effects of genistein, daidzein and quercetin in human erythrocytes and rat microsomes in vitro. Their reducing potential against oxidation of a redox sensitive fluorescent probe, their protective effect against H2O2-induced membrane lipid peroxidation and their inhibitory effect on AAPH-induced hemolysis were evaluated. Genistein and daidzein were prooxidant in erythrocytes but antioxidant in microsomes where their metabolites might have been formed which suggests the importance of metabolic capacity in in vitro models to predict the physiological situation. Quercetin showed antioxidant effects in all models and conditions. Prooxidant effect of ‘genistein-daidzein mixture’, at their concentrations reflecting the real life, was suppressed by addition of quercetin to the mixture. Our study shows that flavonoids can exert prooxidant effects depending on the conditions, but the mixture effect should be considered while assessing their effects and safety in humans. [ABSTRACT FROM AUTHOR]

With the launch of dedicated satellite gravity missions, starting with CHAllenging Minisatellite Payload (CHAMP) in 2000, with Gravity Recovery and Climate Experiment (GRACE) in 2002, and Gravity field and steady-state Ocean Circulation Explorer (GOCE) in 2009, the accuracy and spatial resolution of the Earth's global gravity field models have been improved. Highly sensitive accelerometer measurements have not only been useful for gravity field modeling but have also been contributing to the studies of thermospheric dynamics. While improving the sensitivity of the accelerometer measurements, the new instrumentation used on board GOCE brings different challenges in understanding the data and developing sophisticated data processing. Our analyses reveal that the GOCE gravitational gradient measurements were affected by highly variable ionospheric dynamics that did not only degrade the quality of the GOCE Electrostatic Gravity Gradiometer (EGG) measurements but also proved that some characteristics of ionospheric dynamics can be measured by GOCE accelerometers and other Low Earth Orbiters. In this paper, we show how GOCE-retrieved neutral winds respond to main ionospheric currents and we develop the impulse-response relation between intense ionospheric dynamics (plasma drift) represented by Poynting energy flux and the gravity gradiometer tensor trace disturbances observed over the north geomagnetic polar region. [ABSTRACT FROM AUTHOR]

Participation in regular physical activity reduces the risk of developing diabetes, cardiovascular and other lifestyle-dependent diseases. Interestingly, acute and strenuous exercise influences platelet function and platelet leukocyte interaction as well as blood coagulation and fibrinolysis. However, the underlying mechanisms of these interactions are still completely understood. Accordingly, in the present study we investigated the effect of High-intensity endurance competition (HIC) on platelet function and activity. In addition, we investigated also effects of blood lactate (BLa) on platelet function. 40 healthy (20 male, 20 female) volunteer juvenile swimmers aged 12-13 years performed strenuous exercises at 100% of BLa which corresponded to about 80% of peak oxygen consumption (peak VO2). Blood samples were taken after 30 min rest and immediately after exercise and after 30 min rest. All parameters after exercise were significantly higher than those of before exercise and recovery period. Recovery PF4, PAI-1 and t-PA levels also were significanlty increased than before exercise levels. In conclusion, the effect of the acute arm exercise on platelet aggregation depends on the intensity of exercise and the sensitivity of the membrane and intracellular signalling pathways of platelets. Exercise-induced platelet aggregation occurred without an increase in ATP release. The haemodynamic changes after the exercises, result in an increased shear rate, the increase after strenuous exercise is more pronounce. Therefore, it is recommended that submaximum endurance performance should be individually developed in order for everyone to be able to carry out normal daily activities and also to exercise well below the IAT. [ABSTRACT FROM AUTHOR]

In this study, Al matrix composites consisting of different amounts of Zn, Cu, and Mg were produced using the powder metallurgy technique. In the alloying, powders were ball milled for 120 min via mechanical alloying. After alloying process, the powders were pressed at 800 MPa at room temperature. Sintering (2 h at 600°C in argon atmosphere), solution treatment (2 h at 480°C), and aging processes (3, 6, 9, and 12 h, respectively, at 120°C) were applied to the samples. The hardness and tribo-metallurgy properties of the products were investigated. After sintering, the hardness values of the three alloys were close to each other; however, the solution treatment after sintering caused the hardness values to increase significantly. It was determined that the Al-2Zn-5Cu-4Mg alloy had the highest hardness increase with the 6-h aging heat treatment. The wear resistance of the materials in all the compositions had increased. The highest wear resistance and lowest friction coefficient were obtained for the Al-2Zn-5Cu-4Mg alloy with the 6-h aging heat treatment.

Copyright of Journal of Microbiology & Infectious Diseases is the property of Journal of Microbiology & Infectious Diseases and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Concrete is the most commonly used structural material, which is composed of individual base materials. The compressive strength of concrete is important to understand for activities like construction arrangement, prestressing operations, proportioning new mixtures and quality assurance. Concrete has a problem known as Clustering, which is the unsupervised classification of patterns into clusters. The clustering problem has been addressed by several researchers in many contexts and various disciplines; this shows that clustering uses many areas and is an important step in data analysis. In this study, concrete samples with different aggregate types and normal strength were produced. Clustering analysis was performed on the effect of aggregate species for its mechanical strength. According to the result of clustering analysis, it was found that there were three different groups, the study predicts that clustering is not related to the origins of the rocks but is clustered between the strength of the rocks and the mechanical strengths of the concretes produced within these rocks. The common feature of L, RL and SG aggregates in the first cluster is that it is a sedimentary rock. The aggregate of the concrete in the second cluster is that it is a volcanic superficial rock. The common feature of DO and TB rocks in the third cluster is that it has high density. As a result, it was determined that the clay made in normal class concrete is related to the mechanical strength of rocks.

Copyright of Journal of Pediatric Infection / Çocuk Enfeksiyon Dergisi is the property of Journal of Pediatric Infection / Cocuk Enfeksiyon Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Loss of specific immunity after hematopoietic SCT (HSCT) is well documented for polio, measles, mumps and tetanus. There are limited studies reporting the loss of Hepatitis A virus immunity and no reports evaluating the effect of donor immunity on Hepatitis A virus (HAV) immunity loss after HSCT. A total of 49 of the 81 patients who received HSCT at the Ankara University Pediatric HSCT Unit from January 1997 to December 2006 had HAV serology tested before HSCT and were evaluated for seroprevalence, and 30 of 49 patients were evaluated for the loss of Ab and for the effect of donor immunity on the loss of HAV Abs. The seroprevalence before HSCT was 75.5%. Loss of Ab was detected in 43.5% (10/23) of the patients. The median time to loss of Ab was 12 months (12–32 months), and 60% of these patients were seronegative at 12 months after HSCT. After HSCT, 46.7% of the patients were seronegative. Loss of Ab was higher in the seronegative donor group (75 vs 26%). The loss of HAV Ab is high after allogeneic HSCT for pediatric patients. Reimmunization should be considered for the continuation of individual and community immunity. Further studies with larger study groups are warranted to clarify the role of donor immunity on the loss of HAV immunity. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Pediatric Infection / Çocuk Enfeksiyon Dergisi is the property of Journal of Pediatric Infection / Cocuk Enfeksiyon Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aim: Varicella is predominantly a childhood disease in non-vaccinated populations. The purpose of the study is to evaluate the indications of hospital admissions, complications of varicella infection and their clinical characteristics among previously healthy and children.with underlying illness Material and Methods: Hospital records of children hospitalized for varicella between January 2000 and August 2007 were reviewed. Results: A total of 34 children were hospitalized during the study period, 38% of the patients were previously healthy and 62% were previously ill patients. Previously well children were hospitalized because of varicellarelated complications and previously ill children were usually hospitalized for antiviral therapy or for observation. There were 25 complications in 21 patients. The most common complication was secondary bacterial infections reported in 8 children (23%) and was more common in healthy children (p<0.01). Hepatitis and arthritis were present in 3 (9%), thrombocytopenia, varicella pneumonia and stomatitis were present in 2 (6%) and disseminated varicella and encephalitis were present in 1 (3%) patient. There was no statistically significant difference in the frequency of hepatitis, arthritis, stomatitis, varicella pneumoniae, thrombocytopenia, encephalitis, and disseminated varicella between previously ill and well children (p<0.05). Varicella-related complications observed in healthy children were more severe than the ones observed in previously ill patients. Conclusion: Our study confirms that healthy children are at risk for severe complications of varicella, especially secondary bacterial infections, leading to hospitalization. Thus, an universal childhood varicella immunization may reduce the rate of varicella-related complications and admissions in our country. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Pediatric Infection / Çocuk Enfeksiyon Dergisi is the property of Journal of Pediatric Infection / Cocuk Enfeksiyon Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The major goal of this study is to assess the frequency of psychiatric disorders in end-stage renal disease (ESRD) patients, who were on hemodialysis (HD) treatment in Turkey. Additionally, it aims to determine whether depression, anxiety, and functional and occupational levels of patients who did not receive any psychiatric treatments change at the end of 6 months. We conducted Structured Clinical Interview for the DSM-IV, Clinical Version on 50 HD patients, and 16 (32%) fulfilled the criteria for a psychiatric disorder. Depressive disorder, not otherwise specified, was observed in 12 (24%) patients. Adjustment disorder with depressed mood and dysthymic disorder were observed in 8% of our population. Fourteen patients were followed up for 6 months. All patients were assessed with Hamilton Depression (HDRS), Anxiety Rating Scale (HARS), and Global Assessment of Functioning (GAF) at baseline and at 6 months. The comparisons of baseline and 6 months HDRS, HARS, and GAF scale scores did not reveal any statistically significant differences in 14 depressed patients. The level of depression, anxiety, and functional and occupational impairment did not remit spontaneously in our untreated depressed HD patients. We believe that further studies regarding categorization, prognosis, and treatment of these patients are needed to better understand what to do when we encounter depressive ESRD patients. [ABSTRACT FROM AUTHOR]

: Familial Mediterranean fever (FMF) is an autosomal recessive disorder. Although the pathogenesis of the disease is not yet completely understood, enhanced acute-phase responsiveness is considered to be one of the most important mechanisms. The presence of high levels of antistreptolysin O (ASO) antibodies and streptococcus-associated diseases, such as acute poststreptococcal glomerulonephritis (AGN) and acute rheumatic fever (ARF), has been reported in patients with FMF. In order to better understand the effect of FMF on antistreptococcal antibody response, we measured ASO and antideoxyribonuclease B (anti-DNAse B) levels in patients with FMF and compared them with those in healthy controls. The study consisted of two parts. In the first step, antistreptococcal antibody levels were analysed in 44 patients with FMF and 165 healthy children who had no history or clinical evidence of upper respiratory tract infection (URTI) for the last 4 months. In the second step, antistreptococcal antibody levels were measured in 15 patients with FMF and 22 healthy controls in response to documented group A β-haemolytic streptococcal pharyngitis. In the first part of the study, ASO and anti-DNAse B levels in patients with FMF were found to be significantly higher than those in healthy controls (P<0.001). In the second part, ASO and anti-DNAse B titres were found to be significantly higher in patients with FMF than in controls (P<0.001 and <0.05, respectively) 4 weeks after a positive throat culture. We concluded that patients with FMF have an exaggerated response to streptococcal antigens and might be prone to poststreptococcal non-suppurative complications, such as ARF. [ABSTRACT FROM AUTHOR]

Abstract: A male infant was born to a 24-year-old mother (gravida 1 para 1) by cesarean delivery at 33 1/7 weeks of gestation. The physical examination revealed a large mass protruding from the baby''s mouth, which appeared to be attached to the palate. Tracheostomy was performed immediately in the delivery room. A partial surgical excision was performed on the second postnatal day, removing most of the teratoma (epignathus), which was attached to the back of the pharynx and protruding from the baby''s mouth measuring 13×11×9 cm and weighing 545 g. The final pathological diagnosis was “malignant epignathus with nephroblastoma component.” According to our knowledge, this is the first case that have malignant epignathus including nephroblastoma component in the literature. [Copyright &y& Elsevier]

Central nervous system tuberculosis (TB) is the most devastating manifestation of TB. It is a challenge for clinicians because of the difficulty in making an early diagnosis and the severe consequences of delayed treatment. The aim of this report is to point out the relation between migration and TB based on a 14-year-old child with tuberculous meningoencephalitis (TBM) of an immigrant family. Migration, crowded living conditions and positive family history contribute to the severe course of TB as TBM and miliary TB forms. TB control may prevent these severe manifestations of the disease among immigrants. Prompt diagnosis with helpful early diagnostic tools like polymerase chain reaction in TBM is crucial due to the high mortality and morbidity. [ABSTRACT FROM AUTHOR]

Copyright of Medical Bulletin of Haseki / Haseki Tip Bulteni is the property of Galenos Yayinevi Tic. LTD. STI and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Pediatric Infection / Çocuk Enfeksiyon Dergisi is the property of Journal of Pediatric Infection / Cocuk Enfeksiyon Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)