Non-invasive detection and assessment of coronary stenosis from blood mean residence times.

Coronary artery stenosis is an abnormal narrowing of a coronary artery caused by an atherosclerotic lesion that reduces lumen space. Fractional flow reserve (FFR) is the gold standard method to determine the severity of coronary stenosis based on the determination of rest and hyperemic pressure fields, but requires an invasive medical procedure. Normal FFR is 1.0 and FFR RT, to account for varying volume and flow rate of individual segments. BloodRT was computed in 100 patients who had undergone the pressure-wire FFR procedure, and a threshold for BloodRT was determined to assess the physiological significance of a stenosis, analogous to the diagnostic threshold for FFR. The threshold exhibited excellent discrimination in detecting significant from non-significant stenosis compared to the gold standard pressure-wire FFR, with sensitivity of 98% and specificity of 96%. When applied to clinical practice, this could potentially allow practicing cardiologists to accurately assess and quantify the severity of coronary stenosis without resorting to invasive catheter-based techniques. The first 100 patient study required a clinically determined blood flow rate as a key model input. To create a more non-invasive process, a multiple linear regression approach was employed to determine blood flow rate entering a given artery segment. To validate this method, BloodRT was computed for a new set of 100 patients using the regression derived blood flow rate. The sensitivity and specificity were 95% and 97%, respectively, indicating similar discrimination compared to the clinically derived flow rate. The method was also applied to a succession of stenosis in series. When BloodRT of each individual stenosis was well above the threshold for significance, the cumulative effect of all stenoses led to an overall BloodRT below the threshold of hemodynamic significance

Electronic structure and transport from density matrices and density functionals

As a link between theory and experiment, computational physics has received increasingattention in the last decades. Powerful supercomputers provide the possibility of accuratecalculations for large systems, while highly advanced experimental tools allow researchers toconduct experiments on mesoscopic scale. Such developments lead to a bigger overlap areabetween these two fields of physics. On the other hand, computational approaches are based on theories that are under constantenhancement in order to obtain more accurate results, and therefore, both application andtheory development have crucial role in this field of physics. In the present dissertation, we contribute to the both parts. In the first part, we apply the density functional approach on carbon-nanotube-based systems, and we study the effect of defects addatoms, impurities, and their periodicity on the electronic transport properties of the systems. We also predict the formation of Schottky barrier in the junction between two metallic and semiconducting nanotubes. The second part is dedicated to study the challenges and difficulties in time dependent reduced density matrix approaches. We show that the current approximations make the time evolution of two-body reduced density matrix very unstable. We study the possible reasons behind such behavior, and this might lead us to more stable approximations

In-Distribution and Out-of-Distribution Self-supervised ECG Representation Learning for Arrhythmia Detection

This paper presents a systematic investigation into the effectiveness of Self-Supervised Learning (SSL) methods for Electrocardiogram (ECG) arrhythmia detection. We begin by conducting a novel distribution analysis on three popular ECG-based arrhythmia datasets: PTB-XL, Chapman, and Ribeiro. To the best of our knowledge, our study is the first to quantify these distributions in this area. We then perform a comprehensive set of experiments using different augmentations and parameters to evaluate the effectiveness of various SSL methods, namely SimCRL, BYOL, and SwAV, for ECG representation learning, where we observe the best performance achieved by SwAV. Furthermore, our analysis shows that SSL methods achieve highly competitive results to those achieved by supervised state-of-the-art methods. To further assess the performance of these methods on both In-Distribution (ID) and Out-of-Distribution (OOD) ECG data, we conduct cross-dataset training and testing experiments. Our comprehensive experiments show almost identical results when comparing ID and OOD schemes, indicating that SSL techniques can learn highly effective representations that generalize well across different OOD datasets. This finding can have major implications for ECG-based arrhythmia detection. Lastly, to further analyze our results, we perform detailed per-disease studies on the performance of the SSL methods on the three datasets

Motivations, emotions, and feelings of self gifting entrepreneurs: A cross-cultural study

Purpose- This study explores the self-gifting customer behavior of entrepreneurs across two cultures, Eastern and Western of districts of Iran, and identifies the motivations and feelings associated with the self-gifting practice. Design/methodology/approach- The research includes a literature review of feelings and motiva-tions in the buying context, culture and the importance of cross-cultural studies in the consumer be-havior context, and the concept of self-gifting and its evolution. An empirical research undertaken to explore the feelings and motivations for self-gifting among consumers from six different providences divided in an equal numerical manner to represent the two different cultures. The findings of this qualitative research are analyzed by categorizing the responses into five dimensions or themes which have been identified as most relevant. This was followed by a cross-cultural comparison for each of the previously identified themes. Findings- With the exception of two interviewees who by the nature of their job pay attention to ad-vertisements the rest of the respondents ignored any commercial in this respect. Taking into consider-ation the findings that motives and feelings vary across cultures it can be suggested that ads that try to encourage a self-gifting behavior in Eastern provinces should not follow solely the Western approach. In contrast with the Western individual prioritization, Eastern people are group-oriented thus a self-gift is meant to be shared. Research limitations/implications- In order to avoid any cultural mistake and a low target rate of response self-gifting message customization is advisable. For instance, in West durable and expensive products can be advertised as self-gifts while in the East consumable products and products suitable for sharing can benefit from self-gift-oriented messages. In contrast, experiential self-gifts such as trips can be marketed in a similar way in both East and West. Due to the lack of financial support and time constraints the interviews were not preceded by a complete series of pilot studies. In addition to this, the qualitative analysis as such is vulnerable from the point of view of generalisability, validity and reliability. The interpretivist research philosophy adopted that focuses on the uniqueness of the individuals can also be considered a barrier towards absolute generalisability. Thus, no universal ap-plication of the studies‟ results has been assumed. However, the study gives some useful insights into the nature of self-gifting behavior across the division East-West and as such provides material for future research on the topic. Research paper Reference to this paper should be made as follows: JamehBozorgi, M. J., Hashemi Dashtaki, S.H. (2014). “Motivations, emotions, and feelings of self gifting entrepreneurs: A cross-cultural study”, Journal of Entrepreneurship, Business and Economics, Vol. 2, No. 2, pp. 98–120

EVALUATION OF ACL AND MCL STRAIN UNDER NON-CONTACT LOADING OF LOWER EXTREMITIES USING A HYBRID CADAVERIC SYSTEM

The purpose of this study was to determine the strain in the ACL and MCL under simulated athletic activities using a novel hybrid robotic/cadaveric simulator. Four cadaveric knees, with ACL and MCL instrumented with strain transducers, were tested under simulated jump landing conditions from a height of 30 cm with various degrees of valgus orientation (fixed hamstring and quadricep forces) and various Quadriceps (Q) and Hamstring (H) force levels (fixed degrees of valgus). The response of Anterior Cruciate Ligament (ACL) and Medial Collateral Ligament (MCL) were monitored and assessed during the dynamic loading conditions. 4 – 5 tests were completed for each cadaveric leg, totalling 48 – 64 total tests. Analysis of data revealed that muscle activation (Q&H), in anticipation of landing, reduces the ACL strain even under severe valgus orientations. However, MCL strain is not influenced heavily by muscle activation

Dynamic multivariate loss and risk assessment of process facilities

Dynamic risk assessments (DRA) are the next generation of risk estimation approaches that help to enable safer operations of complex process systems in changing environments. By incorporating new evidences from systems in the risk assessment process, the DRA techniques ensure estimation of current risk. This thesis investigates the existing knowledge and technological challenges associated with dynamic risk assessment and proposes new methods to improve effective implementation of DRA techniques. Risk is defined as the combination of three attributes: what can go wrong, how bad could it be, and how often might it happen. This research evaluates the limitations of the methodologies that have been developed to answer the latter two questions. Loss functions are used in this work to estimate and model operational loss in process facilities. The application of loss functions provides the following advantages: (i) the stochastic nature of losses is taken into account; and (ii) the estimation of the operational loss in process facilities due to the deviation of key process characteristics (KPC) is conducted. Models to estimate reputational loss and significant elements of business interruption loss, which are usually ignored in the literature, are also provided. This research also presents a methodology to develop multivariate loss functions to measure the operational loss of multivariate process systems. For this purpose, copula functions are used to link the univariate loss functions and develop the multivariate loss functions. Copula functions are also used to address the existing challenge of loss aggregation for multiple-loss scenarios. Regarding the dynamic estimation of the probability of abnormal events, the Bayesian Network (BN) has usually been used in the literature. However, integrated safety analysis of hazardous process facilities calls for an understanding of both stochastic and topological dependencies, going beyond traditional BN analysis to study cause-effect relationships among major risk factors. This work presents a novel model based on the Copula Bayesian Network (CBN) for multivariate safety analysis of process systems, which addresses the main shortcomings of traditional BNs. The proposed CBN model offers great flexibility in probabilistic analysis of individual risk factors while considering their uncertainty and complex stochastic dependence. The research outcomes provide advanced methods for critical operations, such as the offshore operations in harsh environments, to be used in continuous improvement of processes and real-time risk estimation. Application of the proposed dynamic risk assessment framework, along with a proper safety culture, enhances the day-to-day risk-informed decision making process by constantly monitoring, evaluating and improving the process safety performance

Therapeutic Value of CD73 as a Biomarker in Human Cancer

Context: Over the past several years, biomarkers have emerged as a diagnostic and therapeutic tool for cancer therapy. CD73 (ecto-5'-nucleotidase) which is a cell surface ectonucleotidase, mediates the conversion of extracellular Adenosine monophosphate (AMP) into adenosine through the purinergic signaling pathway. In this study the role of CD73 in different human cancers was investigated. Evidence Acquisition: The present study reviewed the articles related to the importance of CD73 as a therapeutic tool in human cancers which were published from 1990 to 2019. The publications were found by searching the valid databases for instance PubMed, Google Scholar, ProQuest, Scopus and Science Direct using keywords CD73, ectonucleotidase, therapy, cancer, etc. During the review process 90 articles were selected. Results: Different studies about the effect of CD73 on human malignancies show that CD73 is overexpressed in various types of cancer. Recent findings demonstrate that the extracellular adenosine can promote tumor growth and invasion. The significant regulatory role of CD73 has made it a suitable biomarker for cancer treatment. Conclusion: This study outlines the impact of CD73 on tumor growth, metastasis and angiogenesis. The findings are promising and can highlight the efficacy of this protein as a therapeutic tool in the context of anti-CD73 cancer therapy

Comparison of efficacy between manipulation and exercise therapy in the treatment of patients with Sacroiliac joint dysfunction: A randomized clinical trial

Background: Sacroiliac joint dysfunction is one of the main sources of lower back pain affects 16-30% of these patients. Various treatments had proposed for subluxation and sacroiliac syndrome but the current evidence on this subject is not confirmatory and few surveys have assessed the efficacy of manipulation in the treatment of this condition. The present study aimed to compare the efficacy of manipulation with exercise therapy in patients with sacroiliac pain syndrome. Materials and Methods: In this single-blinded clinical trial, the 30 patients categorized (to two groups) to receive either manipulation or exercise therapy. Required data gathered via medical history and the Persian translation of the Beck and Oswestry questionnaires and the pain assessed according to the visual analogue scale (VAS). Data entered into SPSS v.22 software for analysis. Results: Changes in VAS (p=0.011) and Oswestry score (p=0.012) after one week were significantly greater in the manipulation group. In addition, changes in the Oswestry disability index (ODI) score in the manipulation group of one week and one month after treatment were significantly different from the pre-treatment. Conclusion: Based on the findings of this survey, manipulation had a better efficacy on pain severity and disability of patients with sacroiliac pain syndrome, compared to exercise therapy and considering its low risks and non-invasiveness, its application by trained physicians recommended

A Rare presentation of neurobrucellosis in a child with Recurrent transient ischemic attacks and pseudotumor cerebri (A case report and review of literature)

How to Cite This Article: Akhondian J, Ashrafzadeh F, Beiraghi Toosi M, Hashemi N. A Rare Presentation of Neurobrucellosis in A Child with Recurrent Transient Ischemic Attacks and Pseudotumor Cerebri (A Case Report and Review of Literature). Iran J Child Neurol. 2014 Spring; 8(2):65-69. Brucellosis is a multi-system infectious disease that presents with various manifestations and complications. Neurobrucellosis is an uncommon but serious presentation of brucellosis that can be seen in all stages of the disease. Highindex of suspicion, especially in endemic areas is essential to prevent morbidity from this disease.The case was an 11- year -old female patient who was admitted with a severe headache that was worsening over a period of 2 months. The day after each attack, she experienced transient right hemiparesia that was lasting less than one hour (TIA) as well as blurred vision and bilateral papilledema. Laboratory findings revealed serum agglutination Wright test positive at 1/320 and 2ME test positive at 1/160. A lumbar puncture showed a clear CSF with increased opening pressure (32 cmH2O), CSF examination was within normal range (pseudotumor cerebri).To our knowledge, there has been no report for recurrent TIA in pediatric neurobrucellosis in the base of pseudotumor cerebri.In endemic areas like Iran, unexplained neurological signs or symptoms should be evaluated for brucellosis. References1. Pappas G, Akritidis N, Bosilkovski M, Tsianos E. Brucellosis. N Engl J Med 2005; 352 2325-2336.2. Young EJ, Mandel GL, Bennett JE, et al. Principles and practice of infectious diseases. Philadelphia: Churchill Livingstone; 2002; Pp:23 86-93.3. Gul HC, Erdem H, Bek S. Overview of neurobrucellosis: a pooled analysis of 187 cases. Int J Infect Dis. 2009;13(6):339-343.4. McLean DR, Russell N, Khan MY. Neurobrucellosis: Clinical and therapeutic features. Clin Infect Dis. 1992; 15:582-90.5. Young EJ, Douglas M. Brucella species. Bennett’s principles and practice of infectious diseases. 6th ed. Churchill Livingstone Co. 2005; 6: 2669-73.6. Fatima ZO, Samer Z, Ropert A. Neurobrucellosis in children. Developmental Medicine & Child Neurol.1997;39:762-765.7. Habib YKR, AL – Najdi AKN, Sadek SAH. Paediatric Neurobrucellosis: Case Report and Literature Review. J Infection 1998; 37:59-62.8. Bucher A, Gaustad P, Pape E. Chronic neurobrucellosis due to Brucella melitensis. Scand J Infect Dis 1990; 22:223-6.9. Al Deeb SM, Yaqub BA, Sharif HS, et al. Neurobrucellosis: clinical characteristics, diagnosis, and outcome. Neurology 1989; 39:498-501.10. Shakir RA, Al-Din ASN, Araj GF, et al. Clinical categories of neurobrucellosis; a report on 19 cases. Brain. 1987;110: 213-223.11.Haji-Abdolbagi M, Rasooli-Nejad M, Jafari S, et al. Clinical and laboratory findings in neurobrucellosis: Review of 31 Cases. Arch Iranian Med 2008; 11 (1): 21-25.12. Ranjbar M, Rezaiee AA, Hashemi SH, et al. Neurobrucellosis: report of a rare disease in 20 Iranian patients referred to a tertiary hospital. Eastern Mediterranean Health Journal. 2009; 15(1): 143-148.13. Sturniolo G, Mondello P, Bruno S, et al. Neurobrucellosis associated with syndrome of inappropriate antidiuretic hormone with resultant diabetes insipidus and hypothyroidism. Journal of clinical microbiology. 2010; 48(10): 3806-3809.14. Trifiletti RR, Restivo DA, Pavone P, et al. Diabetes insipidus in neurobrucellosis. Clin Neurol Neurosurg. 2000; 102: 163- 165.15. Zaidan R, Al Tahan AR. Cerebral venous thrombosis: a new manifestation of neurobrucellosis. Clin Infect Dis.1999; 28: 399 - 400.16. Namiduru M, Karaoglan I, Yilmaz M. Guillain-Barre syndrome associated with acute neurobrucellosis. Int J Clin Pract. 2003; 57: 919 - 920.17. Tuncer-Ertem G, Tülek N, Yetkin MA. Case report: subdural hemorrhage in neurobrucellosis. Mikrobiyol Bul. 2004; 38: 253 - 256.18. Tena D, Gonzáles-Praetorius A, López- Alonso A, Peña JL, Pérez-Pomata MT, Bisquert J. Acute meningitis due to Brucella spp. Eur J Pediatr 2006; 165:726-727.19. Salih M A, Abdel G M. Abdel G, et al. Infectious and in ammatory disorders of the circulatory system as risk factors for stroke in Saudi children. Saudi Med J. 2006;27: 41-52.20. Sayyahfar Sh, Karimi A, Fahimzad A , et al. Rare presentation of neurobrucellosis. Pak J Med Sci. 2008; 24(3): 464-467.21. Hernandez MA, Anciones B, Frank A, et al. Neurobrucellosis and cerebral vasculitis. Neurologia 1988; 3:241-243.22. Adaletli I, Albayram S, Gurses B, et al. Vasculopathic changes in the cerebral arterial system with neurobrucellosis. Am J Neuroradiol 2006; 27:384-386.23. Bingöl A, Togay-Isıkay C. Neurobrucellosis as an exceptional cause of transient ischemic attacks. Eur J Neurol 2006; 13:544-548.24.Elrazak MA. Brucella optic neuritis. Arch Intern Med 1991;151:776-8.25. Karakurum G B, Yerdelen D, Karatas M, et al. Abducens nerve palsy and optic neuritis as initial manifestation in brucellosis. Scand J Infect Dis 2006; 38:721-5.26. Karapinar B, Yilmaz D, Vardar F, et al. Unusual presentation of brucellosis in a child: Acute blindness. Acta Paediatrica. 2005;94:378-80.27. Marques R, Martins C, Machado I, et al. Unilateral optic neuritis as a presentation of neurobrucellosis. Pediatric Reports. 2011; 3(11): 36-38.28. Tali ET, Keskin T, Oznur II, et al. MRI of brucella polyneuritis in a child. Neuroradiology. 1996; 38(1): 190-2.29. Yilmaz M, Ozaras R, Mert A, et al. Abducent nerve palsy during treatment of brucellosis. Clin Neurol Neurosurg 2003; 105:218-20.30. Balcer LJ. Optic neuritis. N Engl J Med 2006; 354:1273-1280.31. Dirge KB. Idiopathic intracranial hypertension. BMJ 2010; 341:109-110.32. Emadoleslamia M, Mahmoudianb T. A case of pseudotumor cerebri and brucellosis. Pediatr Infec Dis J .2007;2: 251-253.33. Yasar anlar F, yalcin S, Secmeer G. Persistant hypoglycorrhachia in neurobrucellosis. pediatr infec j. 1994;13(8):747-8.34. Erdem H, Ulu-Kilic A, Kilic S, et al. Efficacy and tolerability of antibiotic combinations in neurobrucellosis: results of the Istanbul study. Antimicrob Agents Chemother. 2012; 56(3):1523-8.