Micromechanical High-doses Radiation Sensor with Bossed Membrane and Interferometry Optical Read-out

AbstractThe silicon-glass MEMS high-doses radiation sensor with in situ detection, so far not possible in the field of detection of doses above 10 kGy, has been presented. The sensor consists of a chamber filled with the high density polyethylene (HDPE) and a silicon bossed membrane. The radiolysis product of HDPE increases the pressure inside the chamber causing the deflection of the membrane, which is proportional to the pressure, thus to radiation dose. The sensor has been irradiated with high energy electron beam and shows good detectability for 10-40 kGy. The deflection of the membrane has been detected by optical interferometer

Сравнение диагностической эффективности магнитно-резонансной томографии с диффузионно-взвешенным исследованием всего тела и позитронной эмиссионной томографии/компьютерной томографии при определении степени регрессии лимфомы после завершения химиотерапии: Минская шкала и шкала Довиль

Introduction. Positron emission tomography/computed tomography (PET/CT) is a recommended technique for tumor response evaluation in lymphoma after treatment. The possibilities of the whole body magnetic resonance imaging with diffusion-weighted imaging (MRI-DWI) for tumor response evaluation in lymphoma are not well studied. Objective: to compare the diagnostic effectiveness of whole body MRI with a diffusion-weighted imaging (MRI-DWI) and PET/CT in determining tumor response in lymphoma after the end of chemotherapy. Materials and methods. A prospective study included 105 adult patients with lymphoma whounderwent whole body MRI-DWI and PET/CTafter the end of chemotherapy and who were followed-up for at least 6 months. To interpret the MRI-DWI, the 5-level scale (Minsk scale) proposed by us was used. Categories 1–3 were considered a sign of complete tumor response, categories 4–5 were a sign of non-complete response. Results. According to the reference standard, complete tumor response was established in 77% of patients, non-complete response in 23%. The assessment of the tumor response in MRI-DWI and PET/CT matched in 89% of patients. The agreement of MRI-DWI (k =0,76, p=0,000) and PET/CT (k =0,78, p=0,000) with the reference standard is good. The sensitivity, specificity, accuracy, positive and negative prognostic value of MRI-DWI were 66,7%, 100,0%, 92,4%, 100,0%, 91,0%, PET/CT — 83,3%, 95,1%, 92,4%, 83,3%, 95,1%, respectively. The diagnostic effectiveness of the methods is not significantly different (p=0,32). The most common reason for the incorrect determination of the tumor response in MRI-DWI was non-enlarged lymph nodes, and in PET/CT — metabolically active non-tumor diseases. 3-year progression-free survival with negative and positive MRI-DWI results was 93% and 25% (p=0,000), 3-year overall survival — 97% and 70% (p=0,011), respectively. Conclusion. Whole body MRI-DWI and Minsk scale are recommended for use in patients with lymphoma to determine tumor response after the end of chemotherapy as a non-irradiative and effective alternative to PET/CT.Введение. Для оценки степени регрессии лимфомы после химиотерапии рекомендуется использовать позитронную эмиссионную томографию/компьютерную томографию (ПЭТ/КТ). Возможности метода магнитно-резонансной томографии с диффузионно-взвешенным исследованием (МРТ-ДВИ) всего тела при оценке степени регрессии лимфомы изучены недостаточно. Цель: сравнить диагностическую эффективность МРТ-ДВИ всего тела и ПЭТ/КТ при определении степени регрессии лимфомы после завершения химиотерапии. Материалы и методы. В проспективное исследование включены 105 взрослых пациентов с лимфомой, которым после завершения химиотерапии выполнили МРТ-ДВИ всего тела и ПЭТ/КТ и которые находились под наблюдением не менее 6 месяцев. Для интерпретации МРТ-ДВИ использовали предложенную нами 5-уровневую шкалу (Минская шкала). Для интерпретации ПЭТ/КТ использовали 5-уровневую шкалу Довиль. Категории оценки 1–3 считали признаком полной регрессии опухолей, категории 4–5 — признаком неполной регрессии. Результаты. Согласно стандарту диагностики полная регрессия опухолей установлена у 77% пациентов, неполная регрессия — у 23%. Оценка степени регрессии при МРТ-ДВИ и ПЭТ/КТ совпала у 89% пациентов. Согласие МРТ-ДВИ (к =0,76, р=0,000) и ПЭТ/КТ (к =0,78, р=0,000) со стандартом диагностики хорошее. Чувствительность, специфичность, точность, положительное и отрицательное прогностическое значение МРТ-ДВИ составили 66,7; 100,0; 92,4; 100,0 и 91,0%, ПЭТ/КТ — 83,3; 95,1; 92,4; 83,3 и 95,1% соответственно. Диагностическая эффективность методов достоверно не различается (р=0,32). Наиболее частой причиной неверного установления степени регрессии при МРТ-ДВИ были неувеличенные лимфоузлы, при ПЭТ/КТ — метаболически активные неопухолевые заболевания. 3-летняя выживаемость без прогрессирования при отрицательном и положительном результатах МРТ-ДВИ составила 93 и 25% (р=0,000), 3-летняя общая выживаемость — 97 и 70% (р=0,011) соответственно. Выводы. МРТ-ДВИ всего тела и Минская шкала рекомендуются к использованию у пациентов с лимфомой для определения степени регрессии опухолей после завершения химиотерапии как нерадиационная и эффективная альтернатива ПЭТ/КТ

General models in min-max continous location

In this paper, a class of min-max continuous location problems is discussed. After giving a complete characterization of th stationary points, we propose a simple central and deep-cut ellipsoid algorithm to solve these problems for the quasiconvex case. Moreover, an elementary convergence proof of this algorithm and some computational results are presented

How Can the Health System Retain Women in HIV Treatment for a Lifetime? A Discrete Choice Experiment in Ethiopia and Mozambique

Introduction: Option B+, an approach that involves provision of antiretroviral therapy (ART) to all HIV-infected pregnant women for life, is the preferred strategy for prevention of mother to child transmission of HIV. Lifelong retention in care is essential to its success. We conducted a discrete choice experiment in Ethiopia and Mozambique to identify health system characteristics preferred by HIV-infected women to promote continuity of care. Methods: Women living with HIV and receiving care at hospitals in Oromia Region, Ethiopia and Zambézia Province, Mozambique were shown nine choice cards and asked to select one of two hypothetical health facilities, each with six varying characteristics related to the delivery of HIV services for long term treatment. Mixed logit models were used to estimate the influence of six health service attributes on choice of clinics. Results: 2,033 women participated in the study (response rate 97.8% in Ethiopia and 94.7% in Mozambique). Among the various attributes of structure and content of lifelong ART services, the most important attributes identified in both countries were respectful provider attitude and ability to obtain non-HIV health services during HIV-related visits. Availability of counseling support services was also a driver of choice. Facility type, i.e., hospital versus health center, was substantially less important. Conclusions: Efforts to enhance retention in HIV care and treatment for pregnant women should focus on promoting respectful care by providers and integrating access to non-HIV health services in the same visit, as well as continuing to strengthen counseling

Environmental volunteer well-being: managers’ perception and actual well-being of volunteers

Environmental volunteering is known to be able to increase well-being but environmental volunteer well-being has rarely been compared to participant well-being associated with other types of volunteering or nature-based activities. This paper aims to use a multidimensional approach to well-being to explore the immediately experienced and later remembered well-being of environmental volunteers and to compare this to the increased well-being of participants in other types of nature-based activities and volunteering. Furthermore, it aims to compare volunteer managers’ perception of their volunteers’ well-being with the self-reported well-being of the volunteers. Onsite surveys were conducted of practical conservation and biodiversity monitoring volunteers as well as their control groups, walkers and fieldwork students, respectively, to measure general well-being before their nature-based activity and activity-related well-being immediately after their activity. Online surveys of current, former and potential volunteers and volunteer managers in environmental volunteering and other types of volunteering measured remembered volunteering-related well-being and volunteer managers’ perceptions of their volunteers’ well-being. Data were analysed based on Seligman’s multidimensional PERMA (‘Positive emotion’, ‘Engagement’, ‘positive Relationship’, ‘Meaning’, ‘Achievement’) model of well-being. Factor analysis recovered three of the five PERMA elements, ‘engagement’, ‘relationship’ and ‘meaning’, as well as ‘negative emotion’ and ‘health’ as factors. Environmental volunteering significantly improved positive elements and significantly decreased negative elements of participants’ immediate well-being and it did so more than walking or student fieldwork did. Even remembering their volunteering up to six months later, volunteers rated their volunteering-related well-being higher than volunteers rated their well-being generally in life. However, volunteering was not found to have an effect on overall mean well-being generally in life. Volunteer managers did not perceive the significant increase in well-being that volunteers reported during volunteering. Multidimensional well-being assessments offer the potential for volunteer organisations and managers to more systematically understand, support and enhance volunteer well-being

Identification of neural networks that contribute to motion sickness through principal components analysis of fos labeling induced by galvanic vestibular stimulation

Motion sickness is a complex condition that includes both overt signs (e.g., vomiting) and more covert symptoms (e.g., anxiety and foreboding). The neural pathways that mediate these signs and symptoms are yet to identified. This study mapped the distribution of c-fos protein (Fos)-like immunoreactivity elicited during a galvanic vestibular stimulation paradigm that is known to induce motion sickness in felines. A principal components analysis was used to identify networks of neurons activated during this stimulus paradigm from functional correlations between Fos labeling in different nuclei. This analysis identified five principal components (neural networks) that accounted for greater than 95% of the variance in Fos labeling. Two of the components were correlated with the severity of motion sickness symptoms, and likely participated in generating the overt signs of the condition. One of these networks included neurons in locus coeruleus, medial, inferior and lateral vestibular nuclei, lateral nucleus tractus solitarius, medial parabrachial nucleus and periaqueductal gray. The second included neurons in the superior vestibular nucleus, precerebellar nuclei, periaqueductal gray, and parabrachial nuclei, with weaker associations of raphe nuclei. Three additional components (networks) were also identified that were not correlated with the severity of motion sickness symptoms. These networks likely mediated the covert aspects of motion sickness, such as affective components. The identification of five statistically independent component networks associated with the development of motion sickness provides an opportunity to consider, in network activation dimensions, the complex progression of signs and symptoms that are precipitated in provocative environments. Similar methodology can be used to parse the neural networks that mediate other complex responses to environmental stimuli. © 2014 Balaban et al

Metrological aspects of biometric recognition

Na podstawie literatury przedstawione zostały ogólne zasady biometrycznego rozpoznawania osób, idea systemu biometrycznego oraz przyczyny powstawania błędów w takim systemie. Analogia pomiędzy systemem biometrycznym i typowym systemem pomiarowym skłania do zainteresowania się metrologów tą dziedziną pomiarów.The methods of biometric recognition, a structure of biometric systems and errors in the recognition procedure are presented in the paper. The analogy between a biometric and measurement system encourages measurement engineers to take an interest in this area of measurements

Organism`s physical parameters measurements

Pomiary "in vivo" fizykalnych parametrów organizmu ludzkiego wymagają rozwiązania licznych trudności metrologicznych i technicznych. Wiążą się one z małym poziomem mocy oraz wąskim zakresem częstotliwości i obecności składowej stałej, tak charakterystycznymi dla wielkości mierzonych w biomedycynie oraz interferencjami i zakłóceniami pochodzacymi od innych organów i od otoczenia. Zasadniczą wagę ma ponadto zapewnienie bezpieczeństwa pacjenta. Na tle zwięźle przedstawionych problemów, jakie stwarzają metrologom pomiary w biomedycynie zaprezentowano przykład zastosowania bezdotykowego pomiaru temperatury do badania odpowiedzi termicznej wywołanej przez nakłuwanie wykonywane w punktach biologicznej aktywności.Measurement organism`s physical parameters cause special metrological and technical problems. They occur because: a) signals collected from the human organism have low power and narrow frequency band, b) signals originated from the organs interfere useful signal, c) disturbances in clinical environment make dificult receiving biomedical signals, d)both noninvasive and invasive measurements should provide absolute electrical shock protection. For example results of non-contact measurements of temperature changes evoked by needle therapy at biological active points are presented