684 research outputs found
Improving the efficiency of university management : teacher’s performance monitoring as a tool to promote the quality of education
This study aims to examine the essence of education monitoring, its place in the higher education management system and the practical implementation of teacher’s performance monitoring as a tool to promote the quality of education.
The article considers theoretical aspects of monitoring as a tool to promote the quality of education, assesses the performance of the university departments, research and teaching staff and discusses the results and suggestions on how to improve monitoring activities in higher education.
Based on their research and findings, the authors claimed that the monitoring of the performance of the university research and teaching staff on the base of an indicator system in terms of education, methodology, research, organization and counselling services would lead to valid conclusions as to the effective performance of both individual researchers and teachers and university departments, in general.peer-reviewe
Minimizing total flow time under uncertainty using optimality and stability boxes
The stability method to the scheduling problem under un-
certain (interval) processing times is investigated. The applied stability approach combines a stability analysis, a multi-stage decision framework, and a solution concept of a minimal
dominant set of the job permutations
Factors of functioning and development of tourist clusters at regional level
Under the condition of tough competition, lack of proper support for tourist industry at the state level, and necessity for development and bringing this sector to a new level, which consists in capability for offering a consumer a high-quality and competitive product, the necessity for search for effective solutions is obvious. One of the perspective and effective means for solving the problems of tourist sphere at present is formation and development of tourist clusters. The article studies existing approaches to determination of tourist cluster, analyzes the current state of internal tourism, and views factors which hinder the creation of competitive product and factors which stipulate the increase of effectiveness of functioning of tourist clusters at regional level
Spatial beam self-cleaning and supercontinuum generation with Yb-doped multimode graded-index fiber taper based on accelerating self-imaging and dissipative landscape
We experimentally demonstrate spatial beam self-cleaning and supercontinuum generation in a tapered Ytterbium-doped multimode optical fiber with parabolic core refractive index profile when 1064 nm pulsed beams propagate from wider (122 µm) into smaller (37 µm) diameter. In the passive mode, increasing the input beam peak power above 20 kW leads to a bell-shaped output beam profile. In the active configuration, gain from the pump laser diode permits to combine beam self-cleaning with supercontinuum generation between 520-2600 nm. By taper cut-back, we observed that the dissipative landscape, i.e., a non-monotonic variation of the average beam power along the MMF, leads to modal transitions of self-cleaned beams along the taper length
Liver cancer disparities in New York City: A neighborhood view of risk and harm reduction factors
© 2018 Kamath, Taioli, Egorova, Llovet, Perumalswami, Weiss, Schwartz, Ewala and Bickell. Introduction: Liver cancer is the fastest increasing cancer in the United States and is one of the leading causes of cancer-related death in New York City (NYC), with wide disparities among neighborhoods. The purpose of this cross-sectional study was to describe liver cancer incidence by neighborhood and examine its association with risk factors. This information can inform preventive and treatment interventions. Materials and methods: Publicly available data were collected on adult NYC residents (n = 6,407,022). Age-adjusted data on liver and intrahepatic bile duct cancer came from the New York State Cancer Registry (1) (2007-2011 average annual incidence); and the NYC Vital Statistics Bureau (2015, mortality). Data on liver cancer risk factors (2012-2015) were sourced from the New York City Department of Health and Mental Hygiene: (1) Community Health Survey, (2) A1C registry, and (3) NYC Health Department Hepatitis surveillance data. They included prevalence of obesity, diabetes, diabetic control, alcohol-related hospitalizations or emergency department visits, hepatitis B and C rates, hepatitis B vaccine coverage, and injecting drug use. Results: Liver cancer incidence in NYC was strongly associated with neighborhood poverty after adjusting for race/ethnicity (β = 0.0217, p = 0.013); and with infection risk scores (β = 0.0389, 95% CI = 0.0088-0.069, p = 0.011), particularly in the poorest neighborhoods (β = 0.1207, 95% CI = 0.0147-0.2267, p = 0.026). Some neighborhoods with high hepatitis rates do not have a proportionate number of hepatitis prevention services. Conclusion: High liver cancer incidence is strongly associated with infection risk factors in NYC. There are gaps in hepatitis prevention services like syringe exchange and vaccination that should be addressed. The role of alcohol and metabolic risk factors on liver cancer in NYC warrants further study
Коморбидность у больных лобулярным панникулитом-липодерматосклерозом
Lipodermatosclerosis (LDS) is one of the variants of lobular panniculitis. The onset of LDS falls on the age of 50–60 years, when many patients already have comorbid pathology requiring complex therapy, which affects the course, the choice of treatment and prognosis of LDS, as well as the quality of life.Objective: to study the structure and frequency of comorbid conditions in patients with LDS.Patients and methods. 53 patients (3 men and 50 women), 18–80 years old, with a verified diagnosis of LDS were included, all of them had an average follow up of 10 years (they were observed in the V.A. Nasonova Research Institute of Rheumatology). The duration of the disease ranged from 2 weeks to 20 years. During clinical examination, the localization, prevalence, color and number of affected skin areas and sub cutaneous fat were determined. The intensity of pain on palpation of the node was assessed using a visual analogue scale (VAS). Laboratory and instrumental research included: blood and urine tests, computed tomography of the chest and ultrasound Doppler of the lower extremities with registration of the linear blood flow velocity in the affected veins (femoral, popliteal, posterior tibial, foot veins). Clinical, laboratory and instrumental examination of patients was carried out 2 times a year. The CIRS and Charlson indices were used to assess the relationship between comorbid pathology and LDS.Results and discussion. Most patients (60.3%) were women with increased body weight (91.5±21.8 kg). Depending on the duration of the disease, the main variants of the LDS course were: acute (<3 months), subacute (3–6 months), and chronic (>6 months). Skin changes were associated with polyarthralgia (34%) and/or myalgia (22.6%), mainly on the side of the affected limb. In 16 patients, an increase in ESR, on average 23.8±7.8 mm per hour, was detected, in 7 patients, including 4 with an acute course of LDS, – more than a threefold increase in the level of CRP. No comorbid diseases had 17 patients, 64.7% of them were under 50 years and had an acute course of LDS (p=0.02). In 68% of patients, mainly with chronic LDS, the following concomitant diseases was recorded: chronic venous insufficiency (CVI; in 67.9%); exogenous constitutional obesity (in 60.3%); rheumatic diseases (45.2%), including osteoarthritis (75%), rheumatoid arthritis (17%), antiphospholipid syndrome (8%), and arterial hypertension (39.6%). Most patients had 1 concomitant disease, and almost one fifth of patients had 2 concomitant diseases. The proportion of patients with 3 comorbid pathologies was 11.1%, with 4 – 8.3% and with 5 – 5.5%. When assessing the Charlson index, a 10-year survival rate of >90% (index values from 0 to 2 points) was observed in 66% of patients, 53–77% (3–4 points) – in 26.4% and <21% (≥5 points) – in 7.5%. There was correlation between the comorbidity index and the age of patients (r=0.8, p<0.05); no association with the duration of LDS was found (r=0.3, p=0.2). Patients over 61 years had ≥1 comorbid disease. The average CIRS index for this group was 4.2±0.3 points (0–10), in most patients (45.2%) it was <5 points. Analysis of the Charlson and CIRS scales confirmed their statistically significant relationship (r=0.5, p=0.0000001).Conclusion. In patients with LDS, a high incidence of comorbid pathology was noted. Interdisciplinary approach with interaction between doctors of different specialties is required for treatment of these patients.Липодерматосклероз (ЛДС) – один из вариантов лобулярного панникулита. Дебют ЛДС приходится на возраст 50–60 лет, когда у многих пациентов уже имеется коморбидная патология, требующая комплексной терапии, что оказывает влияние на течение, выбор тактики лечения и прогноз ЛДС, а также на качество жизни.Цель исследования – изучение структуры и частоты коморбидных состояний у пациентов с ЛДС.Пациенты и методы. Обследовано 53 пациента (3 мужчин и 50 женщин) 18–80 лет с верифицированным диагнозом ЛДС, наблюдавшихся в ФГБНУ «Научно-исследовательский институт ревматологии им. В.А. Насоновой» в среднем 10 лет. Продолжительность заболевания варьировалась от 2 нед до 20 лет. При клиническом обследовании определяли локализацию, распространенность, окраску и количество пораженных участков кожи и подкожной жировой клетчатки. Интенсивность боли при пальпации узла оценивали по визуальной аналоговой шкале (ВАШ). Лабораторно-инструментальное исследование включало: анализы крови и мочи, компьютерную томографию органов грудной клетки и ультразвуковую допплерографию нижних конечностей с регистрацией линейной скорости кровотока в заинтересованных венах (бедренных, подколенных, задних большеберцовых, стопы). Клиническое, лабораторное и инструментальное обследование больных осуществляли 2 раза в год. Для оценки взаимосвязи коморбидной патологией с течением ЛДС использовали индексы CIRS и Charlson.Результаты и обсуждение. Среди пациентов преобладали женщины (60,3%) с повышенной массой тела (91,5±21,8 кг). В зависимости от длительности заболевания были выделены основные варианты течения ЛДС: острое (<3 мес), подострое (3–6 мес) и хроническое (>6 мес). Изменения кожи ассоциировалось с полиартралгиями (34%) и/или миалгиями (22,6%), преимущественно на стороне пораженной конечности. У 16 пациентов зарегистрировано повышение СОЭ в среднем до 23,8±7,8 мм/ч, у 7 больных в (том числе у 4 с острым течением ЛДС) – более чем трехкратное увеличение уровня СРБ. У 17 пациентов коморбидных заболеваний не выявлено, 64,7% из них были моложе 50 лет и имели острое течение ЛДС (р=0,02). У 68% больных, преимущественно с хроническим течением ЛДС, зафиксирована следующая сопутствующая патология: хроническая венозная недостаточность (ХВН; у 67,9%), экзогенно-конституциональное ожирение (у 60,3%); ревматические заболевания (у 45,2%), в том числе остеоартрит (у 75%), ревматоидный артрит (у 17%), антифосфолипидный синдром (у 8%), а также артериальная гипертензия (у 39,6%). У большинства пациентов имелось 1 сопутствующее заболевание, практически у пятой части – 2. Доля пациентов с 3 коморбидными патологиями составила 11,1%, с 4 – 8,3% и 5 – 5,5%. При оценке индекса Charlson показатель 10-летней выживаемости >90% (значения индекса от 0 до 2 баллов) отмечен у 66% больных, 53–77% (3–4 балла) – у 26,4% и <21% (≥5 баллов) – у 7,5%. Обнаружена взаимосвязь индекса коморбидности с возрастом пациентов (r=0,8, p<0,05), ассоциации с продолжительностью ЛДС не установлено (r=0,3, p=0,2). У больных старше 61 года зафиксировано ≥1 коморбидное состояние. Индекс CIRS для данной группы составлял в среднем 4,2±0,3 балла (0–10), у большинства больных (45,2%) он был <5 баллов. При анализе шкал Charlson и CIRS подтверждена их статистически значимая связь (r=0,5, р=0,0000001).Заключение. У больных ЛДС отмечена высокая частота коморбидной патологии. Курация больных требует междисциплинарного подхода и взаимодействия между врачами разных специальностей
Long-Time Asymptotics of Perturbed Finite-Gap Korteweg-de Vries Solutions
We apply the method of nonlinear steepest descent to compute the long-time
asymptotics of solutions of the Korteweg--de Vries equation which are decaying
perturbations of a quasi-periodic finite-gap background solution. We compute a
nonlinear dispersion relation and show that the plane splits into
soliton regions which are interlaced by oscillatory regions, where
is the number of spectral gaps.
In the soliton regions the solution is asymptotically given by a number of
solitons travelling on top of finite-gap solutions which are in the same
isospectral class as the background solution. In the oscillatory region the
solution can be described by a modulated finite-gap solution plus a decaying
dispersive tail. The modulation is given by phase transition on the isospectral
torus and is, together with the dispersive tail, explicitly characterized in
terms of Abelian integrals on the underlying hyperelliptic curve.Comment: 45 pages. arXiv admin note: substantial text overlap with
arXiv:0705.034
On the Cauchy Problem for the Korteweg-de Vries Equation with Steplike Finite-Gap Initial Data I. Schwartz-Type Perturbations
We solve the Cauchy problem for the Korteweg-de Vries equation with initial
conditions which are steplike Schwartz-type perturbations of finite-gap
potentials under the assumption that the respective spectral bands either
coincide or are disjoint.Comment: 29 page
Cosmic Rays: The Second Knee and Beyond
We conduct a review of experimental results on Ultra-High Energy Cosmic Rays
(UHECR's) including measurements of the features of the spectrum, the
composition of the primary particle flux and the search for anisotropy in event
arrival direction. We find that while there is a general consensus on the
features in the spectrum -- the Second Knee, the Ankle, and (to a lesser
extent) the GZK Cutoff -- there is little consensus on the composition of the
primaries that accompany these features. This lack of consensus on the
composition makes interpretation of the agreed upon features problematic. There
is also little direct evidence about potential sources of UHECRs, as early
reports of arrival direction anisotropies have not been confirmed in
independent measurements.Comment: 46 pages, 30 figures. Topical Review to appear in J. Physics
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