The Effects of Thermal Procedure on Transformation Temperature, Crystal Structure and Microstructure of Cu-Al-Co Shape Memory Alloy

The purpose of this study is to investigate the effects of different thermal procedures of the Cu-Al-Co shape memory alloy on its crystal structure, transformation temperature and microstructure. The alloys were subjected to a heat treatment and then cooling was applied at four different conditions. After the thermal process, XRD, DSC, optical microscopy and micro-hardness measurements were carried out. The experimental studies showed that crystal structure, microstructure and transformation temperature of Cu-Al-Co alloy were changed from the cooling conditions

Effective-Mass Dirac Equation for Woods-Saxon Potential: Scattering, Bound States and Resonances

Approximate scattering and bound state solutions of the one-dimensional effective-mass Dirac equation with the Woods-Saxon potential are obtained in terms of the hypergeometric-type functions. Transmission and reflection coefficients are calculated by using behavior of the wave functions at infinity. The same analysis is done for the constant mass case. It is also pointed out that our results are in agreement with those obtained in literature. Meanwhile, an analytic expression is obtained for the transmission resonance and observed that the expressions for bound states and resonances are equal for the energy values $E=\pm m$.Comment: 20 pages, 6 figure

Outbreak of Phytophthora cinnamomi causing severe decline of avocado trees in southern Turkey

Acknowledgements: This research was supported by Bati Akdeniz Agricultural Research Institute (BATEM), and we appreciate the help of the staff of the Ministry of Agriculture and Forestry. We are also thankful to Dr Emrah Yıldırım for preparation of the map.Peer reviewedPostprin

On the physical nudging equations

In this work we show how it is possible to derive a new set of nudging equations, a tool still used in many data assimilation problems, starting from statistical physics considerations and availing ourselves of stochastic parameterizations that take into account unresolved interactions. The fluctuations used are thought of as Gaussian white noise with zero mean. The derivation is based on the conditioned Langevin dynamics technique. Exploiting the relation between the Fokker-Planck and the Langevin equations, the nudging equations are derived for a maximally observed system that converges towards the observations in finite time. The new nudging term found is the analog of the so called quantum potential of the Bohmian mechanics. In order to make the new nudging equations feasible for practical computations, two approximations are developed and used as bases from which extending this tool to non-perfectly observed systems. By means of a physical framework, in the zero noise limit, all the physical nudging parameters are fixed by the model under study and there is no need to tune other free ad-hoc variables. The limit of zero noise shows that also for the classical nudging equations it is necessary to use dynamical information to correct the typical relaxation term. A comparison of these approximations with a 3DVar scheme, that use a conjugate gradient minimization, is then shown in a series of four twin experiments that exploit low order chaotic models

Factors associated with non-invasive ventilation response on the first day of therapy in patients with hypercapnic respiratory failure

BACKGROUND AND AIM: Noninvasive ventilation (NIV) decreases mechanical ventilation indication in the early period of acute hypercapnic respiratory failure (AHcRF) and factors for success have been studied well. But, less is known about the factors influencing the NIV response in the subacute period. This study was aimed to determine the factors influencing the reduction of PaCO(2) levels within first 24 hours of therapy. METHODS: NIV response was defined as reduction of PaCO(2) level below 50 mmHg within first 24 hours. Patients with AHcRF, treated with NIV, were divided into 2 groups according to this criterion; group 1 as the nonresponsive, group 2 as the responsive. The differences in NIV methods and characteristics of the two groups were evaluated and compared in this retrospective study. RESULTS: A total of 100 patients were included in the study; 66 of them in group 1 and 34 in group 2. No significant differences were identified between the length of NIV application and intensive care unit (ICU) stay, intubation and mortality rates, across the groups. Ninety-one percent of the patients in group 2 had received all night long NIV therapy; this was just 74% in group 1 (P=0.036). Results of multivariate analysis showed that while nocturnal application was significantly associated with better response, prior home ventilation and requirement of higher pressure support (PS) levels significantly and independently associated with poorer response to NIV therapy. CONCLUSION: In patients with AHcRF, all night long use of NIV may accelerate healing by improving PaCO(2) reduction within the first 24 hours. A rapid response in PaCO(2) levels should not be expected in patients requiring higher PS levels and using prior home ventilation

Three-dimensional modelling of the femur and humerus in adult male guinea pigs (guinea pig) with computed tomography and some biometric measurement values

Background: Guinea pig is a species belonging to the Caviidae family of the Rodentia order and is frequently used in experimental studies. Biomedical imaging methods are used in the diagnosis and treatment of many diseases in medicine. Among these methods, computed tomography (CT) is one of the most important imaging methods. In this study, it was aimed to perform the three-dimensional (3D) modelling of the CT images, obtained from the humerus and femur in the guinea pigs, via the MIMICS programme, and to make some biometric measurements regarding the bones over these models. Materials and methods: In the present study, 12 male adult guinea pigs were used. The soft tissue on the humerus and femur bones of the guinea pigs was removed. After this procedure, CT images at a 0.5 mm-thickness were obtained from the animals. The images were recorded in DICOM format. Then, the reconstruction process was performed from the images by using the 3D modeling programme MIMICS® 13.1. On the 3D model of the humerus and femur (right-left), volumes, surface areas and lengths as well as other biometric parameters were measured separately, and the values were recorded. In addition, measurements of the bones were made with the help of a digital calliper. Results: Among the parameters obtained from 3D models, a statistical difference was observed between the right and left cortical thicknesses of the femur from the measurements of calliper and the right and left humerus volumes (p < 0.05); whereas, no statistical difference was found in other parameters of both measurements (p > 0.05). Conclusions: It can be stated that CT and 3D modelling can be used for the measurement of some parameters in the long bones of the guinea pigs

Kawasaki disease: report of two cases

Kawasaki hastalıgı sistemik bir vaskülittir. En çok orta boy arterleri tutar. Gelismis ülkelerde çocuklarda edinsel kalp hastalıklarının en sık nedenidir. Halen etiolojisi ve patogenezi tam aydınlatılmamıstır. Koroner arter etkilenmesine baglı ani ölüm ve kronik hastalık riski intravenöz immünglobulin tedavisi sonrası belirgin azalmaktadır. Bu nedenle erken ve dogru tanı prognoz açısından çok önemlidir. Kawasaki hastalıgı tanısı konan iki olgumuzun birinde ekokardiyogramda sol ana koroner arterde dilatasyon saptandı. Diger olguda kardiyak lezyon yoktu. Koroner arter ektazisi izlemde geriledi. Bu makalede, iki olgu nedeniyle Kawasaki hastalıgı'nın tanısı, tedavi ve izlem ilkeleri tartısılmıstır.Kawasaki disease is a systemic vasculitis. It affects medium-sized arteries most commonly. In developed countries, it is the most common reason for acquired cardiac diseases in children. Etiology and pathogenesis of the disease have not yet been completely clarified. Risk of sudden death or chronic cardiac disease due to coronary artery lesions are highly decreased after intravenous immunoglobulin therapy. Thus, early and correct diagnosis is of utmost importance for favorable outcome. In one of the two cases with Kawasaki disease, left main coronary artery was dilated on the echocardiogram. The other patient had no cardiac lesion. Coronary artery ectasia was observed to be regressed. In this paper, due to the two cases, diagnosis, treatment and follow-up principles of Kawasaki disease were discussed

Two patientswith aseptic meningitis and immune trombocytopenic purpura following chickenpox

Suçiçeği, Varicella Zoster virüsünün (VZV) primer enfeksiyonudur. VZV viremisine bağlı olarak iç organ ve santral sinir sistemi tutulumu gözlenebilir. Nörolojik komplikasyonlar, suçiçeği enfeksiyonu geçiren çocukların hastaneye en sık yatış endikasyonları arasındadır. Üstelik tipik deri döküntüsü olmadan da görülebilirler. Suçiçeğinin hemorajik komplikasyonları çocuklukta nadirdir. İmmün yetmezliklilerde trombositopeniyle birlikte yaygın hemorajik döküntülere yol açabilir. Trombositopeni suçiçeğini izleyen 1-2 hafta içinde gözlenebileceği gibi daha geç de ortaya çıkabilir. Bu makalede, suçiçeği enfeksiyonundan sonra gelişmiş aseptik menenjitli 7 yaşında erkek olgu ile immun trombositopenik purpuralı (İTP) 6 yaşında erkek olgu sunulmuştur. Her iki olguda da iyileşen suçiçeği döküntüleri vardı. Aseptik menenjitli olgu spontan iyileşirken, İTP'li olgu metil prednizolon tedavisine yanıt verdi. Bu iki olgu nedeniyle suçiçeğinin komplikasyonlu seyredebileceği ve aşı ile korunmanın önemi vurgulanmıştır.Chickenpox is the primary infection of varicella zoster virus. The viscera and central nervous system can be affected due to viremia of VZV. Neurologic complications are among the most frequent indications for hospitalization of children with varicella. Furthermore, they can be seen in the absence of characteristic cutaneous rash. Haemorrhagic complications of varicella are rare in childhood. Varicella can cause trombocytopenia and disseminated hemorrhagic lesions in immunocompromised children. Trombocytopenia maybegin 1to 2weeks ormore after varicella. In this paper,a sevenyear oldmalewith asepticmeningitis and a six year oldmalewithimmune trombocytopenic purpura (ITP) following varicella are presented. Both of them had resolving cutaneous rashes of varicella. The patient with aseptic meningitis recovered spontaneously; on the otherhand, the patient with ITP responded to metil prednisolone treatment.Due to these two cases, it is stressed that varicella can be complicated and it can be prevented withvaccine

Approximate k-state solutions to the Dirac-Yukawa problem based on the spin and pseudospin symmetry

Using an approximation scheme to deal with the centrifugal (pseudo-centrifugal) term, we solve the Dirac equation with the screened Coulomb (Yukawa) potential for any arbitrary spin-orbit quantum number {\kappa}. Based on the spin and pseudospin symmetry, analytic bound state energy spectrum formulas and their corresponding upper- and lower-spinor components of two Dirac particles are obtained using a shortcut of the Nikiforov-Uvarov method. We find a wide range of permissible values for the spin symmetry constant C_{s} from the valence energy spectrum of particle and also for pseudospin symmetry constant C_{ps} from the hole energy spectrum of antiparticle. Further, we show that the present potential interaction becomes less (more) attractive for a long (short) range screening parameter {\alpha}. To remove the degeneracies in energy levels we consider the spin and pseudospin solution of Dirac equation for Yukawa potential plus a centrifugal-like term. A few special cases such as the exact spin (pseudospin) symmetry Dirac-Yukawa, the Yukawa plus centrifugal-like potentials, the limit when {\alpha} becomes zero (Coulomb potential field) and the non-relativistic limit of our solution are studied. The nonrelativistic solutions are compared with those obtained by other methods.Comment: 21 pages, 6 figure

Arctic sea ice data assimilation combining an ensemble Kalman filter with a novel Lagrangian sea ice model for the winter 2019–2020

Advanced data assimilation (DA) methods, widely used in geophysical and climate studies to merge observations with numerical models, can improve state estimates and consequent forecasts. We interface the deterministic ensemble Kalman filter (DEnKF) to the Lagrangian neXt generation Sea Ice Model, neXtSIM. The ensemble is generated by perturbing the atmospheric and oceanic forcing throughout the simulations and randomly initialized ice cohesion. Our ensemble–DA system assimilates sea ice concentration (SIC) from the Ocean and Sea Ice Satellite Application Facility (OSI-SAF) and sea ice thickness (SIT) from the merged CryoSat-2 and SMOS datasets (CS2SMOS). Because neXtSIM is computationally solved on a time-dependent evolving mesh, it is a challenging application for ensemble–DA. As a solution, we perform the DEnKF analysis on a fixed and regular reference mesh, on which model variables are interpolated before the DA and then back to each member's mesh after the DA. We evaluate the impact of assimilating different types of sea ice observations on the model's forecast skills of the Arctic sea ice by comparing satellite observations and a free-run ensemble in an Arctic winter period, 2019–2020. Significant improvements in modeled SIT indicate the importance of assimilating weekly CS2SMOS SIT, while the improvements of SIC and ice extent are moderate but benefit from daily ingestion of the OSI-SAF SIC. For most of the winter, the correlation between SIT and SIC is weaker, which results in little cross-inference between the two variables in the assimilation step. Overall, the ensemble–DA system based on the stand-alone sea ice model demonstrates the feasibility of winter Arctic sea ice prediction with good computational efficiency. These results open the path toward operational implementation and the extension to multi-year assimilation.</p