80 research outputs found
Production of magnesium-aluminium bimetallic bars using the explosive cladding method
The paper presents the results of the preparation of semi-finished products in the form of magnesium-aluminium round bimetallic bars by the explosive cladding method. The system of samples consisted of an aluminium tube (1050 grade) and magnesium bar (grade AZ31) was prepared. The analysis of microstructure and mechanical tests of the joint quality was carried out. On the base of obtained results it was found that the explosive cladding parameters used to obtain the semi-finished bimetallic product characterized by a slight ovality and mechanical connection of the individual layers were correct
Impulse Stimulated Crystallization in Amorphous Semiconducting Films
Coordinated Science Laboratory was formerly known as Control Systems LaboratoryJoint Services Electronics Program / DAAB-07-72-C-025
Correlations between selected parameters of nasal cavity in neonates and young infants — computed tomography study
Background: Correlations between selected metric parameters of the nasal cavity and nasopharynx in children without atresia may be useful for anticipating probable dimensions of this region in living subjects, in terms of changes with age.
Materials and methods: One hundred and eighty children, age range 0–3 years, were divided into five age groups, and measurements of 18 distances between structures of nasal cavity and nosopharynx were performed on computed tomography scans. Correlation coefficients and relations between parameters have been determined.
Results: Our study confirmed the existence of statistically significant correlations between linear dimensions within nasal cavity in children. The analysis demonstrated that for the values of following indexes: nasal septum length/piriform aperture width, and maximum length of the nasal septum/posterior nares width no statistically significant differences have been noted between age groups of children. All correlations have been positive. No statistically significant differences have been noted between the maximum width of the vomer and osseous parameters measured, both in the anterior and posterior part of the nasal cavity, and nasal septum length.
Conclusions: The size of posterior nares changed with age in children by a constant value. So far, no such an analysis has been carried out assessing potential correlations between linear dimensions for the entire nasal cavity, nasopharynx, length of the nasal septum in children, as well as proportions of individual linear dimensions of the anatomical structures analysed, in various age groups
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Patterns of initiation of second generation antipsychotics for bipolar disorder: a month-by-month analysis of provider behavior
Background: Several second generation antipsychotics (SGAs) received FDA approval for bipolar disorder in the 2000s. Although efficacious, they have been costly and may cause significant side effects. Little is known about the factors associated with prescribers’ decisions to initiate SGA prescriptions for this condition. Methods: We gathered administrative data from the Department of Veterans Affairs on 170,713 patients with bipolar disorder between fiscal years 2003–2010. Patients without a prior history of taking SGAs were considered eligible for SGA initiation during the study (n =126,556). Generalized estimating equations identified demographic, clinical, and comorbidity variables associated with initiation of an SGA prescription on a month-by-month basis. Results: While the number of patients with bipolar disorder using SGAs nearly doubled between 2003 and 2010, analyses controlling for patient characteristics and the rise in the bipolar population revealed a 1.2% annual decline in SGA initiation during this period. Most medical comorbidities were only modestly associated with overall SGA initiation, although significant differences emerged among individual SGAs. Several markers of patient severity predicted SGA initiation, including previous hospitalizations, psychotic features, and a history of other antimanic prescriptions; these severity markers became less firmly linked to SGA initiation over time. Providers in the South were somewhat more likely to initiate SGA treatment. Conclusions: The number of veterans with bipolar disorder prescribed SGAs is rising steadily, but this increase appears primarily driven by a corresponding increase in the bipolar population. Month-by-month analyses revealed that higher illness severity predicted SGA initiation, but that this association may be weakening over time
Treatment of irritable bowel syndrome with diarrhoea using titrated ondansetron (TRITON): study protocol for a randomised controlled trial
Background: Irritable bowel syndrome with diarrhoea (IBS-D) affects up to 4% of the general population. Symptoms
include frequent, loose, or watery stools with associated urgency, resulting in marked reduction of quality of life and
loss of work productivity. Ondansetron, a 5HT3 receptor antagonist, has had an excellent safety record for over 20 years
as an antiemetic, yet is not widely used in the treatment of IBS-D. It has, however, been shown to slow colonic transit
and in a small randomised, placebo-controlled, cross-over pilot study, benefited patients with IBS-D.
Methods: This trial is a phase III, parallel group, randomised, double-blind, multi-centre, placebo-controlled trial, with
embedded mechanistic studies. Participants (n = 400) meeting Rome IV criteria for IBS-D will be recruited from
outpatient and primary care clinics and by social media to receive either ondansetron (dose titrated up to 24 mg daily)
or placebo for 12 weeks. Throughout the trial, participants will record their worst abdominal pain, worst urgency, stool
frequency, and stool consistency on a daily basis.
The primary endpoint is the proportion of “responders” in each group, using Food and Drug Administration (FDA)
recommendations. Secondary endpoints include pain intensity, stool consistency, frequency, and urgency. Mood and
quality of life will also be assessed.
Mechanistic assessments will include whole gut transit, faecal tryptase and faecal bile acid concentrations at baseline
and between weeks 8 and 11. A subgroup of participants will also undergo assessment of sensitivity (n = 80) using the
barostat, and/or high-resolution colonic manometry (n = 40) to assess motor patterns in the left colon and the impact
of ondansetron.
Discussion: The TRITON trial aims to assess the effect of ondansetron across multiple centres. By defining
ondansetron’s mechanisms of action we hope to better identify patients with IBS-D who are likely to respond
Low fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAP) diet improves symptoms in adults suffering from irritable bowel syndrome (IBS) compared to standard IBS diet: A meta-analysis of clinical studies
BACKGROUND: Irritable bowel syndrome (IBS) and functional digestive tract disorders, e.g. functional bloating, carbohydrate maldigestion and intolerances, are very common disorders frequently causing significant symptoms that challenge health care systems. A low Fermentable Oligosaccharides, Disaccharides, Monosaccharides and Polyols (FODMAP) diet is one of the possible therapeutic approaches for decreasing abdominal symptoms and improving quality of life. OBJECTIVES: We aimed to meta-analyze data on the therapeutic effect of a low-FODMAP diet on symptoms of IBS and quality of life and compare its effectiveness to a regular, standard IBS diet with high FODMAP content, using a common scoring system, the IBS Symptom Severity Score (IBS-SSS). METHODS: A systematic literature search was conducted in PubMed, EMBASE and the Cochrane Library as well as in the references in a recent meta-analysis. Adult patients diagnosed with IBS according to the Rome II, Rome III, Rome IV or NICE criteria were included in the analysis. STATISTICAL METHODS: Mean differences with 95% confidence intervals were calculated from studies that contained means, standard deviation (SD) or mean differences and SD of differences and p-values. A random effect model was used because of the heterogeneity (Q test (chi2) and I2 indicator). A p-value of less than 0.05 was chosen to indicate a significant difference. RESULTS: The literature search yielded 902 publications, but only 10 were eligible for our meta-analysis. Both regular and low-FODMAP diets proved to be effective in IBS, but post-diet IBS-SSS values were significantly lower (p = 0.002) in the low-FODMAP group. The low-FODMAP diet showed a correlation with the improvement of general symptoms (by IBS-SSS) in patients with IBS. CONCLUSIONS: This meta-analysis provides high-grade evidence of an improved general symptom score among patients with irritable bowel syndrome who have maintained a low-FODMAP diet compared to those on a traditional IBS diet, therefore showing its superiority to regular IBS dietary therapy. These data suggest that a low-FODMAP diet with dietitian control can be a candidate for first-line therapeutic modality in IBS. Because of a lack of data, well-planned randomized controlled studies are needed to ascertain the correlation between improvement of separate key IBS symptoms and the effect of a low-FODMAP diet
The effects of TNF-alpha inhibitor therapy on the incidence of infection in JIA children
Juvenile Idiopathic arthritis (JIA) is the most common chronic rheumatic disease in childhood. The diagnosis is based on the underlying symptoms of arthritis with an exclusion of other diseases Biologic agents are increasingly used on the side of disease-modifying anti-rheumatic drugs (DMARD) in JIA treatment.The aim of this meta-analysis was to investigate the observed infections in JIA children during tumor necrosis factor (TNF)-alpha inhibitor therapy. A systematic search of three databases (Medline via PubMed, Embase, Cochrane Library) was carried out up to May 2018. Published trials that evaluated the infectious adverse events in patients receiving TNF-alpha inhibitor vs. a control group were included in the analysis. Full-text data extraction was carried out independently by the investigators from ten relevant publications. 1434 patients received TNF-alpha inhibitor therapy; the control group consisted of 696 subjects. The analysis presented the risk of infection in the active treatment group (OR = 1.13; 95% CI: 0.76-1.69; p = 0.543). The majority of infections were upper respiratory tract infections (URTIs). Furthermore, the subgroup analysis demonstrated a higher infection rate in the observed localization.Anti-TNF therapy slightly but not significantly increases the incidence of infection in JIA children compared to other therapies (GRADE: moderate evidence). The most common infections reported were mild URTIs. Further studies with larger patients number with a strong evidence level are crucially needed to finalize the answer whether anti-TNF therapy elevates and if yes on what extent the incidence of infection in JIA children.Prospero: CRD42017067873
Badanie współzależności poziomów generacji wiatrowej i potencjalnej generacji ze źródeł PV na obszarze ENERGA-OPERATOR SA
This paper presents the results of an analysis of the interdependence of wind generation output
and photovoltaic generation potential in the ENERGA-OPERATOR SA grid. The first study of the
interdependence of these two types of renewable sources’ generation outputs was carried out by
the Gdańsk Branch of the Institute of Power Engineering in cooperation with ENERGA-OPERATOR
in 2012. An important conclusion of the study was the need to repeat the analysis for a larger set
of input data as the study covered the period of one year only, and for obvious reasons a limited
number of wind farms. The present study’s inputs included a period of four years and more wind
farms, due to the continuous connecting of new facilities to the grid.
Thus, the results are characterized by a much higher level of credibility, and allow drawing more
correct conclusions regarding the analysed interdependence. The research on the interdependence
of the annual wind generation output and potential generation from photovoltaic sources
indicates that both generation types are characterized by mutual spatio-temporal dependency.
In the study the relationship was quantified by evaluation of the maximum actual wind generation
output in specific areas in the case of high PV generation output in a given area and vice
versa. The results may allow for appropriate (i.e. substantiating the modelled operating conditions
of the system in relation to reality) consideration of both types of sources in various types of
system analyses of their impact on the grid performance, such as interconnection studies for new
sources and distribution grid development planning.W artykule zostały przedstawione wyniki analizy współzależności poziomów generacji wiatrowej i potencjalnej generacji fotowoltaicznej
na obszarze sieci ENERGA-OPERATOR SA. Pierwsze badania dotyczące przedmiotowej zależności poziomów generacji,
wspomnianych dwóch rodzajów źródeł odnawialnych, zostały przeprowadzone przez Instytut Energetyki Oddział Gdańsk
we współpracy z operatorem w 2012 roku. Jednym z ważnych wniosków pracy było wskazanie konieczności powtórzenia analizy dla
większego zbioru danych wejściowych, ponieważ studium obejmowało okres jednego roku i ograniczoną z oczywistych względów
liczbę lokalizacji farm wiatrowych. W prezentowanych badaniach dane wejściowe obejmowały okres czterech lat oraz większą liczbę
farm wiatrowych, ze względu na ciągłe przyłączanie kolejnych obiektów do sieci. Tym samym otrzymane wyniki charakteryzują
się znacznie wyższym poziomem wiarygodności oraz pozwalają na wyciągnięcie bardziej prawidłowych wniosków dotyczących
współzależności będącej przedmiotem badania. Z przeprowadzonych badań zależności rocznych przebiegów poziomów generacji
wiatrowej i potencjalnej generacji ze źródeł fotowoltaicznych wynika, że oba typy generacji charakteryzują się wzajemną obszarową
zależnością. W ramach pracy związek ten został skwantyfikowany poprzez wyznaczenie wartości maksymalnego realnego
poziomu generacji wiatrowej na poszczególnych obszarach w przypadku wysokiej generacji PV na danym obszarze i vice versa.
Otrzymane wyniki mogą pozwolić na właściwe (uprawdopodobniające modelowane stany pracy systemu w stosunku do rzeczywistości)
uwzględnianie obu typów źródeł w różnych rodzajach analiz systemowych, badających ich wpływ na sieć, takich jak analizy
przyłączeniowe nowych źródeł czy planowanie rozwoju sieci dystrybucyjnej
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