How to reduce the number of rating scale items without predictability loss?

Rating scales are used to elicit data about qualitative entities (e.g., research collaboration). This study presents an innovative method for reducing the number of rating scale items without the predictability loss. The "area under the receiver operator curve method" (AUC ROC) is used. The presented method has reduced the number of rating scale items (variables) to 28.57\% (from 21 to 6) making over 70\% of collected data unnecessary. Results have been verified by two methods of analysis: Graded Response Model (GRM) and Confirmatory Factor Analysis (CFA). GRM revealed that the new method differentiates observations of high and middle scores. CFA proved that the reliability of the rating scale has not deteriorated by the scale item reduction. Both statistical analysis evidenced usefulness of the AUC ROC reduction method.Comment: 14 pages, 5 figure

The dynamics of the non-heme iron in bacterial reaction centers from Rhodobacter sphaeroides

AbstractWe investigate the dynamical properties of the non-heme iron (NHFe) in His-tagged photosynthetic bacterial reaction centers (RCs) isolated from Rhodobacter (Rb.) sphaeroides. Mössbauer spectroscopy and nuclear inelastic scattering of synchrotron radiation (NIS) were applied to monitor the arrangement and flexibility of the NHFe binding site. In His-tagged RCs, NHFe was stabilized only in a high spin ferrous state. Its hyperfine parameters (IS=1.06±0.01mm/s and QS=2.12±0.01mm/s), and Debye temperature (θD0~167K) are comparable to those detected for the high spin state of NHFe in non-His-tagged RCs. For the first time, pure vibrational modes characteristic of NHFe in a high spin ferrous state are revealed. The vibrational density of states (DOS) shows some maxima between 22 and 33meV, 33 and 42meV, and 53 and 60meV and a very sharp one at 44.5meV. In addition, we observe a large contribution of vibrational modes at low energies. This iron atom is directly connected to the protein matrix via all its ligands, and it is therefore extremely sensitive to the collective motions of the RC protein core. A comparison of the DOS spectra of His-tagged and non-His-tagged RCs from Rb. sphaeroides shows that in the latter case the spectrum was overlapped by the vibrations of the heme iron of residual cytochrome c2, and a low spin state of NHFe in addition to its high spin one. This enabled us to pin-point vibrations characteristic for the low spin state of NHFe

Prospective Observational Study on acute Appendicitis Worldwide (POSAW)

Background: Acute appendicitis (AA) is the most common surgical disease, and appendectomy is the treatment of choice in the majority of cases. A correct diagnosis is key for decreasing the negative appendectomy rate. The management can become difficult in case of complicated appendicitis. The aim of this study is to describe the worldwide clinical and diagnostic work-up and management of AA in surgical departments.Methods: This prospective multicenter observational study was performed in 116 worldwide surgical departments from 44 countries over a 6-month period (April 1, 2016-September 30, 2016). All consecutive patients admitted to surgical departments with a clinical diagnosis of AA were included in the study.Results: A total of 4282 patients were enrolled in the POSAW study, 1928 (45%) women and 2354 (55%) men, with a median age of 29 years. Nine hundred and seven (21.2%) patients underwent an abdominal CT scan, 1856 (43.3%) patients an US, and 285 (6.7%) patients both CT scan and US. A total of 4097 (95.7%) patients underwent surgery; 1809 (42.2%) underwent open appendectomy and 2215 (51.7%) had laparoscopic appendectomy. One hundred eighty-five (4.3%) patients were managed conservatively. Major complications occurred in 199 patients (4.6%). The overall mortality rate was 0.28%.Conclusions: The results of the present study confirm the clinical value of imaging techniques and prognostic scores. Appendectomy remains the most effective treatment of acute appendicitis. Mortality rate is low.</p

Prospective Observational Study on acute Appendicitis Worldwide (POSAW)

Acute appendicitis (AA) is the most common surgical disease, and appendectomy is the treatment of choice in the majority of cases. A correct diagnosis is key for decreasing the negative appendectomy rate. The management can become difficult in case of complicated appendicitis. The aim of this study is to describe the worldwide clinical and diagnostic work-up and management of AA in surgical departments.info:eu-repo/semantics/publishedVersio

Analysis of the losses decrease possibilities in transformers

W artykule wskazano na dużą rolę transformatorów rozdzielczych w systemie dystrybucji energii oraz scharakteryzowano technologiczne możliwości zmniejszenia strat jałowych i obciążeniowych. Podano wymagania przepisów UE odnośnie do strat w transformatorach suchych i olejowych oraz możliwości wprowadzenia transformatorów energooszczędnych.The important role of distributing transformers in power distribution system was indicated and technological possibilities unproductive and load losses decrease were characterized. The UE regulations concerning dry and oil transformers losses and possibilities of energy saving transformers were presented in the paper

Czynniki środowiskowe związane z wykorzystaniem biogazu rolniczego

This article includes the theoretical information about biogas, the production process, general information about renewable energy and regulations considering the digestion of manure and other fermentation by-products. The paper however is focused on environmental impacts of agricultural biogas production and utilization. It includes information about possible emissions that can be avoided and their environmental impact. More detailed calculations of the possible annual energy production in Poland are presented in the last part of the article.Czynniki środowiskowe związane z wykorzystaniem biogazu rolniczego W artykule zawarto informacje dotyczące biogazu rolniczego, jego produkcji, ogólne informacje o odnawialnych źródłach energii oraz informacje dotyczące aspektów prawnych fermentacji metanowej gnojowicy oraz późniejszego wykorzystania powstałych w tym procesie produktów. Skupiono się na czynnikach środowiskowych związanych w produkcją i wykorzystaniem biogazu rolniczego. Zawarto informacje dotyczące możliwych do uniknięcia emisji oraz sposobu, w jaki wpływają one na środowisko i człowieka. Zaprezentowano również nieco bardziej szczegółowe obliczenia potencjału energetycznego gnojowicy pochodzącej z hodowli bydła i owiec

Nowoczesne metody odsiarczania stosowane w urządzeniach termicznej utylizacji odpadów

Decreasing the amount of sulfur dioxide emissions is one of the most critical concerns of environmental protection. These substances have huge influence on natural environment as well as on human health. The authors included information about the absorbtion process that takes place in absorbers. Also, the various types of absorbers are presented, along with applications and a short description. There are presented installations placed in Polish waste incineration plants.Nowoczesne metody odsiarczania stosowane w urządzeniach termicznej utylizacji odpadów Zmniejszenie emisji dwutlenku siarki jest obecnie jednym z najważniejszych zagadnień ochrony środowiska. Związki te mają istotny wpływ na środowisko naturalne, w tym zdrowie człowieka. W artykule przedstawiono suche i mokre metody odsiarczania, wraz z ich porównaniem. Zawarto również informacje na temat procesu absorpcji zachodzącego w absorberach. Przedstawiono rodzaje absorberów, ich zastosowanie oraz sposób ich doboru, a także instalacje znajdujące się w polskich spalarniach odpadów