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Background: Alterations in the cerebral venous system have been increasingly recognized as a significant component of the pathophysiology of multiple sclerosis (MS). This study aimed to explore the relationship between venous sinus diameter and MS to understand potential vascular alterations in MS patients compared with controls. We sought to determine whether these alterations were correlated with disease characteristics such as duration, lesion type, and disability score. Methods: This study included 79 MS patients diagnosed according to the 2017 McDonald criteria and 67 healthy individuals. Magnetic resonance imaging (MRI) scans via a 1.5 Tesla system provided measurements of the superior sagittal sinus, right and left transverse sinus, sinus rectus, and venous structures. Statistical analysis was conducted via SPSS, employing independent sample t tests, ANOVA, chi-square tests, and Pearson correlation analysis, with the significance level set at p < 0.05. Results: This study revealed significant differences in venous sinus diameter between MS patients and controls, with MS patients exhibiting larger diameters. Specifically, patients with brainstem and spinal lesions had larger diameters in certain sinus regions. No significant correlations were found between venous sinus diameter and demographic factors, expanded disability status scale scores, or lesion counts. However, a significant increase in perivenular lesions was noted in patients with longer disease durations. Conclusions: The findings indicate notable vascular alterations in MS patients, particularly in venous sinus diameters, suggesting a potential vascular component in MS pathology. The lack of correlation with conventional clinical and MRI metrics highlights the complexity of MS pathology. These insights underscore the need for further research, particularly longitudinal studies, to elucidate the role of venous changes in MS progression and their potential as therapeutic targets. [ABSTRACT FROM AUTHOR]

In this study, an experimental study was carried out on a heat pipe, whose evaporator is located between the compressor outlet and the condenser inlet of an industrial cooler on a vapor compression cycle (VCC). It absorbs heat from the new generation refrigerant fluid of 515B and transfers it to the outdoor air. The heat pipe is a looped thermosiphon-type heat pipe. R134a refrigerant is used as a working fluid in the heat pipe. By changing the condenser air inlet temperatures, the contribution of the heat pipe to the cooling cycle has been determined experimentally. While the evaporation pressure of the refrigeration cycle with the heat pipe remains approximately constant, the condensation pressure decreases, and the sub-cool temperature increases. For condenser air inlet temperatures of 30, 40, and 50°C, the COP of the cooler with heat pipe increases by 1.8%, 2.6%, and 2.76%, respectively. As the air temperature at the condenser inlet increases, the ratio of heat pipe power to the cooling capacity of the cycle also increases. In addition, the compressor outlet temperature is reduced by 1.5%–2.8% using of the heat pipe. [ABSTRACT FROM AUTHOR]

In the 1950s, the concept of artificial intelligence emerged, suggesting that machines could possess the ability to think and learn. In the 21st century, with advancements in GPUs and CPUs, deep learning has become an integral part of human life. Proximal femoral fractures are known to be one of the leading causes of mortality and injuries among the elderly population. This study aims to detect proximal femoral fractures in X-ray images and compare the success of using the YOLOv4 algorithm and provide decision support system within the diagnosis. To retrain the algorithm, more than 500 patients' X-ray images were examined. Through data augmentation techniques, the initial set of 410 patients' femur proximal fracture X-ray images was expanded to 820 images. After retraining the YOLO algorithm, two different groups were included for comparing the algorithm's performance: orthopedic specialists and general practitioners. The results from these three groups were evaluated using specific criteria. The YOLOv4 model demonstrated an accuracy of 90.33%. In comparison, orthopedic and traumatology resident doctors achieved an accuracy of 91.42%, while the general practitioner group achieved an accuracy of 81.30%. [ABSTRACT FROM AUTHOR]

Introduction: Lemmel syndrome occurs when the primarily intrapancreatic portion of the common bile duct is compressed or obstructed by a duodenal diverticulum. This can cause jaundice due to the pressure. Case Presentation: A 65-year-old female patient was admitted to the emergency room with Lemmel syndrome. The patient underwent endoscopic retrograde cholangiopancreatography (ERCP), confirming the diagnosis of a diverticulum. The papilla was located in the diverticulum, and despite various attempts and maneuvers, it could not be cannulated. Subsequently, percutaneous transhepatic cholangiography (PTC) was performed, and an 8F drainage catheter was successfully placed in the duodenum. Conclusion: Lemmel syndrome is a rare condition that may cause acute abdomen with obstructive jaundice. Increased awareness and familiarity with imaging can help distinguish the diverticulum from tumors, potentially saving the patient from unnecessary surgeries. If ERCP fails, PTC may be a successful alternative for the treatment of jaundice. [ABSTRACT FROM AUTHOR]

Battery is one of the largest contributors to the weight of electric vehicles, and its location directly affects the performance of the suspension system. The aim of this article is to determine the optimal battery locations for ride comfort of in-wheel-motor electric automobiles using a nonlinear vehicle suspension model. In the analyses, a seven-degree-of-freedom half-vehicle suspension model was used, in which cubic nonlinearities of all springs and dampers are taken into account in addition to their linear characteristics. In addition to spring and damper nonlinearities, all trigonometric nonlinearities are also considered in the model. Totally 144 different driving scenarios were generated with 48 different sinusoidal road profiles and 3 different travel speeds, and for each scenario by testing 36 battery locations along the vehicle's longitudinal axis, the optimal one was found. The optimization criterion is the minimization of the root-mean-square of the vertical acceleration of the driver and seat. As a result of the 5184 analyses carried out, it has been seen that the optimal battery location is the middle of the vehicle for road profiles with wavelengths between 0.2 and 5 m, whereas the rear of the vehicle for road profiles with wavelengths between 10 and 30 m. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Erciyes Agriculture & Animal Science is the property of Erciyes Tarim ve Hayvan Bilimleri 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.)

Parallel robots have many remarkable advantages over their conventional serial counterparts. Highly accurate positioning capability and high payload-to-weight ratio are among the main ones. The main factor underlying all these advantages is their closed-loop construction. However, this constructional feature also causes a special singularity problem, which constitutes their biggest disadvantage. Characteristic singularities classified as Type II exist inside their workspace, around which the magnitude of the inverse dynamic solution grows unboundedly. This naturally yields the saturation of the actuators and eventually in uncontrollability of the robot. Consequently, the whole workspace becomes impossible to be used. In order to pass through a Type II singularity, the consistency of the motion equations of the robot must be maintained at that singularity. However, any Type II singular configuration can transform into a high-order singularity, which, in order to be passed through, requires additional conditions other than the consistency. Therefore, full utilization of the whole workspace with a minimum number of conditions requires to avoid high-order singularities. The present article contributes to the literature by developing path and trajectory planning principles for preventing a two-degree-of-freedom planar parallel robot with RPRPR structure from experiencing high-order singularities. [ABSTRACT FROM AUTHOR]

Introduction: Functional echocardiography has been used to identify the etiologies of cardiac arrest and to evaluate the benefit of continued resuscitation after cardiac arrest. It gains more importance in the detection of treatable causes, especially in cardiopulmonary resuscitation of newborns with a diagnosed disease that may develop complications such as massive pericardial effusion and thrombosis. Case Report: Here, we present the findings and results of functional echocardiography performed during cardiopulmonary resuscitation of two newborns with neonatal lupus syndrome and congenital nephrotic syndrome. Conclusions: More studies are needed to clarify the usability of functional echocardiography in neonatal cardiopulmonary resuscitation. It is gaining more importance, especially in newborns with a possible diagnosis of complications. The most important situation here is that echocardiography should be performed without affecting the continuity of resuscitation. Accompanied by an experienced user, it will allow rapid identification of reversible causes of cardiac arrest. [ABSTRACT FROM AUTHOR]

Copyright of Sakarya Tıp Dergisi is the property of Sakarya Tip 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.)

Introduction: Gemcitabine is a nucleoside analog antimetabolite used in various malignancies, including metastatic breast cancer. Objective response rates in its use as a single agent in the treatment of metastatic breast cancer are not to be underestimated. Cutaneous, hematological, pulmonary, and vascular side effects are well-known side effects. Venous thromboembolism may occur with antineoplastics, such as platinum compounds. Arterial thromboembolism is rare in cancer, almost rare with chemotherapy. Here, we present a metastatic breast cancer patient who had digital necrosis due to arterial occlusion with gemcitabine monotherapy. Case report: A 54-year-old metastatic breast cancer female patient had digital ischemia and necrosis in the left hand's fifth finger after the second course of single-agent gemcitabine as the fourth line setting. Gemcitabine was discontinued, and medical treatment was started. Thrombus was detected in the left subclavian artery digital angiography. Balloon angioplasty and stenting were applied. However, digital amputation had to be performed since tissue necrosis had not regressed despite radiological interventions and medical treatment. Management and outcome: Gemcitabine was discontinued. Low molecular weight heparin and acetylsalicylic acid were started. The distal phalanx was amputated due to necrosis during follow-up. Gemcitabine was permanently stopped. Discussion: Gemcitabine-related vascular events, including arterial thrombosis, may also occur in cancer patients, especially those with higher tumor burden. Therefore, predisposing factors for hypercoagulability and vascular occlusion should be questioned in more detail even before starting antineoplastics which are known to have a lower risk for thrombosis, such as gemcitabine monotherapy. [ABSTRACT FROM AUTHOR]

The electrical and mechanical properties of carbon fiber-reinforced polymer (CFRP) composites have a close dependence on the use of modifiers like polyvinylpyrrolidone (PVP), as well as on the processing techniques to disperse functional charges such as graphene-related materials into the epoxy base. In the present work, reduced graphene oxide (RGO), prepared by a natural antioxidant agent, astaxanthin, was used as a filler material in the epoxy matrix of the carbon fiber composites. The astaxanthin reduction leads to an increase in the sp2 ordering in RGO; some residual epoxy and C-O groups that enhance the interaction with the epoxy matrix remain after reduction. The effects of RGO and PVP-modified RGO (PVP-RGO) fillers with different contents (0.05, 0.1, and 0.15% wt.) on the electrical conductivity, bending properties, and dynamic mechanical properties of CFRP were investigated. The incorporation of 0.15 wt.% RGO with and without PVP-modification, leads to through-the-thickness (Z-direction testing) conductivity values 7.4 and 9.6 times higher than those of the neat composite, respectively. The conductivity tests indicate that the RGO/epoxy composite behaves as a continuous conductor due to the formation of agglomerates of RGO within the matrix, while at the added contents of the PVP-RGO filler, the composite is below the percolation threshold, then conducting by electron tunneling, due to a better dispersion of the PVP-RGO filler within the epoxy matrix. The dynamic mechanical analysis shows that the glass transition temperature is indicative of the interactions among the filler, the epoxy matrix, and the carbon fiber, that is, the PVP-RGO filler increases the chain mobility due to its higher dispersion in the matrix. While Tg of the neat epoxy/CFRP composite is 92.5°C, a minimum Tg of 88.5°C was achieved with a 0.10 % wt. PVP-RGO filler contents, and a maximum Tg of 94.5°C with a 0.15 % wt. of RGO filler amount. For constant filler content (0.15 wt.%), CFRP composite containing RGO and PVP-modified RGO exhibited 9.73% and 13.87% increase in flexural strength values, respectively, compared to the neat composite. The bending test revealed that PVP modification to RGO is beneficial to improve flexural strength of CFRP composites. Graphical Abstract [ABSTRACT FROM AUTHOR]