Role of Short-Term Percutaneous Mechanical Circulatory Support Devices as Bridge-to-Heart Transplantation

Cardiogenic shock is a life-threatening condition and mortality remains high if there is no response with medical therapy. Recently, short-term percutaneous mechanical circulatory support (pMCS) devices have increased in use for refractory cardiogenic shock. These devices can provide full treatment or bridging to long-term MCS devices if patients need long-term support. There are four types of well-known MCS devices including Impella (Abiomed, Danvers, MA), TandemHeart (CardiacAssist, Pittsburgh, PA), and extracorporeal membrane oxygenation (ECMO) and intra-aortic balloon pump for short-term and percutaneous application. In this chapter, we aim to discuss the physiologic concept, clinical evidences and applications, indications-contraindications, complications, and comparison of these most commonly used short-term pMCS devices for advanced heart failure

ESCADA: Efficient Safety and Context Aware Dose Allocation for Precision Medicine

Finding an optimal individualized treatment regimen is considered one of the most challenging precision medicine problems. Various patient characteristics influence the response to the treatment, and hence, there is no one-size-fits-all regimen. Moreover, the administration of an unsafe dose during the treatment can have adverse effects on health. Therefore, a treatment model must ensure patient \emph{safety} while \emph{efficiently} optimizing the course of therapy. We study a prevalent medical problem where the treatment aims to keep a physiological variable in a safe range and preferably close to a target level, which we refer to as \emph{leveling}. Such a task may be relevant in numerous other domains as well. We propose ESCADA, a novel and generic multi-armed bandit (MAB) algorithm tailored for the leveling task, to make safe, personalized, and context-aware dose recommendations. We derive high probability upper bounds on its cumulative regret and safety guarantees. Following ESCADA's design, we also describe its Thompson sampling-based counterpart. We discuss why the straightforward adaptations of the classical MAB algorithms such as GP-UCB may not be a good fit for the leveling task. Finally, we make \emph{in silico} experiments on the bolus-insulin dose allocation problem in type-1 diabetes mellitus disease and compare our algorithms against the famous GP-UCB algorithm, the rule-based dose calculators, and a clinician.Comment: 23 pages, 12 figure

A Comparative Study of Language Learning Strategies Used by Monolingual and Bilingual Learners

The purpose of this research is to analyze monolingual and bilingual university students’ language learning strategies (LLS) comparatively and to determine whether students’ level of using language learning strategies in foreign language learning process changes in terms of variables such as gender, department and school type. This research was conducted among 524 university students at Yüzüncü Yıl University and Bülent Ecevit University Çaycuma Vocational School. Data of the study was collected by “Strategy Inventory of Language Learning” developed by Oxford (1990) and adapted into Turkish by Cesur and Fer (2007). Data collected was analyzed with descriptive statistics and parametric tests. As a result of the research, it was found that bilingual students use language learning strategies in foreign language learning process more than monolingual students. Furthermore, it was found that university students use language learning strategies at middle level; students mostly use metacognitive strategies and use affective strategies the least; female students use language learning strategies more than male students except cognitive and affective strategies; English language and literature and English language teaching department students use language learning strategies more than department of translation students; 4 years faculty students use language learning strategies more than vocational school students

Near-field Hybrid Beamforming for Terahertz-band Integrated Sensing and Communications

Terahertz (THz) band communications and integrated sensing and communications (ISAC) are two main facets of the sixth generation wireless networks. In order to compensate the severe attenuation, the THz wireless systems employ large arrays, wherein the near-field beam-squint severely degrades the beamforming accuracy. Contrary to prior works that examine only either narrowband ISAC beamforming or far-field models, we introduce an alternating optimization technique for hybrid beamforming design in near-field THz-ISAC scenario. We also propose an efficient approach to compensate near-field beam-squint via baseband beamformers. Via numerical simulations, we show that the proposed approach achieves satisfactory spectral efficiency performance while accurately estimating the near-field beamformers and mitigating the beam-squint without additional hardware components.Comment: Accepted Paper in 2023 IEEE Global Communications Conference (GLOBECOM), Kuala Lumpur, Malaysia, 202

Investigating the Advantages and Limitations of Modeling Physical Mass Transfer of CO2 on Flat Plate by One Fluid Formulation in OpenFOAM

One fluid formulation is an approach used for modeling and analysis of mass transfer between two immiscible phases. In this study we implement and analyze the advantages and limitations of this approach for CO2 physical mass transfer into MEA. The domain is a flat plate and gas liquid flow is counter current. The analysis was carried for operating parameters like liquid phase Reynolds number, MEA mass fraction and the angle of inclination of flat plate. The results clearly show that the model effectively captures the deviation in liquid side mass transfer coefficient due to the surface instabilities and liquid properties which are generally neglected by standard correlations. Also the model shows that the standard Higbie correlation is preferable at low Reynolds number at any angle of inclination. The grid independent studies show that a size of 6.25 µm is required in the interface region for effectively using this approach. The computational resource time at this resolution was found as the only limitation for using this approach and we suggest a procedure to overcome this limitation. The present simulation results can help CFD researchers investigating immiscible gas-liquid mass transfer using OpenFOAM

Antenna Selection With Beam Squint Compensation for Integrated Sensing and Communications

Next-generation wireless networks strive for higher communication rates, ultra-low latency, seamless connectivity, and high-resolution sensing capabilities. To meet these demands, terahertz (THz)-band signal processing is envisioned as a key technology offering wide bandwidth and sub-millimeter wavelength. Furthermore, THz integrated sensing and communications (ISAC) paradigm has emerged jointly access spectrum and reduced hardware costs through a unified platform. To address the challenges in THz propagation, THz-ISAC systems employ extremely large antenna arrays to improve the beamforming gain for communications with high data rates and sensing with high resolution. However, the cost and power consumption of implementing fully digital beamformers are prohibitive. While hybrid analog/digital beamforming can be a potential solution, the use of subcarrier-independent analog beamformers leads to the beam-squint phenomenon where different subcarriers observe distinct directions because of adopting the same analog beamformer across all subcarriers. In this paper, we develop a sparse array architecture for THz-ISAC with hybrid beamforming to provide a cost-effective solution. We analyze the antenna selection problem under beam-squint influence and introduce a manifold optimization approach for hybrid beamforming design. To reduce computational and memory costs, we propose novel algorithms leveraging grouped subarrays, quantized performance metrics, and sequential optimization. These approaches yield a significant reduction in the number of possible subarray configurations, which enables us to devise a neural network with classification model to accurately perform antenna selection.Comment: 14pages10figures, submitted to IEE

One-Stage Combined Thoracic Ancient Schwannomas Total Removal and Coronary Artery Bypass

Ancient schwannoma is a rare variant of neural tumors though rarely seen in the thorax. The combination with coronary artery diseases is also rare. Here we describe a 66 year-old male who had undergone one-stage combined surgery for thoracic ancient schwannomas removal and coronary artery disease. The masses were, respectively, 13 cm in the middle mediastinum and 5 cm in diameter originating from the intercostal nerve. The tumors were successfully removed using sternotomy, and then a coronary artery bypass grafting was performed. Here we discuss this rare tumor in relation to the relevant literature

Segmentation of orbital and periorbital lesions detected in orbital magnetic resonance imaging by deep learning method

Purpose: Magnetic resonance imaging (MRI) has a special place in the evaluation of orbital and periorbital lesions. Segmentation is one of the deep learning methods. In this study, we aimed to perform segmentation in orbital and periorbital lesions. Material and methods: Contrast-enhanced orbital MRIs performed between 2010 and 2019 were retrospectively screened, and 302 cross-sections of contrast-enhanced, fat-suppressed, T1-weighted, axial MRI images of 95 patients obtained using 3 T and 1.5 T devices were included in the study. The dataset was divided into 3: training, test, and validation. The number of training and validation data was increased 4 times by applying data augmentation (horizontal, vertical, and both). Pytorch UNet was used for training, with 100 epochs. The intersection over union (IOU) statistic (the Jaccard index) was selected as 50%, and the results were calculated. Results: The 77th epoch model provided the best results: true positives, 23; false positives, 4; and false negatives, 8. The precision, sensitivity, and F1 score were determined as 0.85, 0.74, and 0.79, respectively. Conclusions: Our study proved to be successful in segmentation by deep learning method. It is one of the pioneering studies on this subject and will shed light on further segmentation studies to be performed in orbital MR images

Histološko i histomorfometrijsko istraživanje kore malog mozga i srebrom obojenih regija nukleolusne organizacije Purkinjeovih neurona u štakora kronično tretiranim morfinom

The effects of chronic morphine administration on the rat cerebellum and silver stained nucleolus organizer regions in Purkinje cells were investigated by means of histological, histochemical and histometrical techniques. Thirty-two young (30-32 days of age) Wistar rats (equal numbers of both genders) were randomly divided into 2 groups, as control and morphine-treated, each having equal numbers of both genders, a total of 16 animals. The control animals were injected subcutaneously with 1mL/kg physiological saline, and the morphine-treated rats received 5 mg/kg morphine hydrochloride subcutaneously at daily intervals for 30 days. The thickness of the molecular and granular layers of the cerebellum, the diameters of the nuclei and nucleoli of cerebellar Purkinje neurones, and the number and size of the silver staining nucleolus organizer regions of the Purkinje cell nuclei were determined histomorphometrically. The morphine administration caused slight histological changes in the cerebellum. The molecular layer thickness of the cerebellum was significantly (P<0.05) reduced, and the decrease was mainly in the male animals. In contrast, the layer thickened insignificantly in the morphine-treated females. The granular layer thickened slightly but insignificantly in both genders of the morphine-treated group. The Purkinje cell count significantly decreased with morphine treatment. Nucleus size did not change with morphine treatment. However, morphine-treated animals had smaller nucleoli. It was concluded that morphine treatment caused significant histomorphological changes in the cerebellar cortex in a sexually dimorphic manner.Učinci kronične primjene morfina na mali mozak štakora i na srebrom obojene regije nukleolusne organizacije Purkinjeovih neurona istraživani su histološkim, histokemijskim i histometrijskim tehnikama. Trideset i dva mlada Wistar štakora (dob 30 - 32 dana), u jednakom omjeru spolova, metodom slučajnog izbora podijeljena su u dvije skupine s po 16 jedinki u svakoj skupini. Životinjama u kontrolnoj skupini potkožno je primijenjen 1 mL/kg fiziološke otopine, dok su životinje u pokusnoj skupini dobile 5 mg/kg morfin hidroklorida, potkožno, svaki dan tijekom 30 dana. Za određivanje zadebljanja molekularnih i granulacijskih slojeva maloga mozga, promjera jezgre i nukleolusa Purkinjeovih neurona u malom mozgu te broja i veličine srebrom obojenih regija nukleolusne organizacije Purkinjeovih neurona primijenjena je histomorfometrijska metoda. Davanje morfina izazvalo je blage histološke promjene u malom mozgu. Debljina molekularnog sloja maloga mozga značajno je smanjena (P<0,05). To je ponajprije bilo izraženo kod životinja muškoga spola, dok je molekularni sloj kod ženki tretiranih morfinom bio tek neznatno zadebljan. Granulirani sloj bio je blago i nesignifikantno zadebljan u oba spola unutar skupine tretirane morfinom. Broj Purkinjeovih stanica značajno je smanjen nakon primjene morfina, dok to nije bio slučaj s veličinom jezgre koja se nije mijenjala. No, životinje koje su dobivale morfin imale su manje nukleole. Zaključeno je da liječenje morfinom uzrokuje značajne histomorfološke promjene u kori maloga mozga, pri čemu važnu ulogu ima spol jedinke