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The growth of hexagonal boron nitride (hBN) on epitaxial Ge(001)/Si substrates via high-vacuum chemical vapor deposition from borazine is investigated for the first time in a systematic manner. The influences of the process pressure and growth temperature in the range of 10−7–10−3 mbar and 900–980 °C, respectively, are evaluated with respect to morphology, growth rate, and crystalline quality of the hBN films. At 900 °C, nanocrystalline hBN films with a lateral crystallite size of ~2–3 nm are obtained and confirmed by high-resolution transmission electron microscopy images. X-ray photoelectron spectroscopy confirms an atomic N:B ratio of 1 ± 0.1. A three-dimensional growth mode is observed by atomic force microscopy. Increasing the process pressure in the reactor mainly affects the growth rate, with only slight effects on crystalline quality and none on the principle growth mode. Growth of hBN at 980 °C increases the average crystallite size and leads to the formation of 3–10 well-oriented, vertically stacked layers of hBN on the Ge surface. Exploratory ab initio density functional theory simulations indicate that hBN edges are saturated by hydrogen, and it is proposed that partial de-saturation by H radicals produced on hot parts of the set-up is responsible for the growth.

The results of our preliminary studies indicated that the diets of predatory fishes can be bioindicators of faunistic changes in ecosystems and indirectly of changes taking place in aquatic environments in the Pomeranian Bay. We examined the diet composition of top predators Gadus morhua, Sander lucioperca, Perca fluviatilis, and the mesopredator Neogobius melanostomus. The diet composition of the perch, pikeperch, and round goby in the Pomeranian Bay was analyzed for the first time. Our findings indicated that perch, an euryphagous species, is the best potential bioindicator because it is present in the area studied most of the year and has a low to moderate feeding index (FI). Baltic cod, also an euryphagous species, could be a good bioindicator in the areas where it is abundant and occurs frequently, but not in the Pomeranian Bay, where it is caught mainly in the fall. Round goby, which is present in the area studied and had a low FI, is a stenophagous species that preys mainly on benthic species, while pikeperch had a very high FI and the least number of prey species in its diet. The results of trophic interaction analysis among the predators analyzed and their non-native/invasive prey are also provided.

The aim of this study was to determine the biological, morphometric, and shape characteristics of the bivalve Rangia cuneata in the initial phase of colonisation. A total of 504 specimens were caught for the study. Their average length was 31.06 mm (range 12.7–43.2 mm) and weight 6.0 g (0.5–15.3 g). The population was dominated by individuals of 25–30 mm and 30–35 mm in length and the age of 3+ and 4+. The standard major axis regression for measurable traits describing shell cross-section indicate the allometric nature of growth for most parameters. Elongation and convexity indices by age group indicate a change in the shell shape as it becomes more elongated and convex in individuals that have already reached sexual maturity. The collected specimens were of larger sizes compared to other Baltic populations of the species, and similar in size to populations found in the neighboring Pomeranian Bay. The increase in length of R. cuneata in the Oder estuary is smaller compared to the species native sites, probably due to the lower water temperature in the study area. Considering the invasive potential of R. cuneata, it seems necessary to monitor closely its population and distribution in the estuary of Western Baltic.

This paper discusses the state of advancement in the development of spectroscopic methods based on the use of mid (proper) infrared radiation in the context of applications in various fields of science and technology. The authors drew attention to the most important solutions specific to both spectroscopy itself (ATR technique) and chemometric data processing tools (PCA and PLS models). The objective of the current paper is to collect and consistently present information on various aspects of FT-IR spectroscopy, which is not only a well-known and well-established method but is also continuously developing. The innovative aspect of the current review is to show FT-IR’s great versatility that allows its applications to solve and explain issues from both the scientific domain (e.g., hydrogen bonds) and practical ones (e.g., technological processes, medicine, environmental protection, and food analysis). Particular attention was paid to the issue of hydrogen bonds as key non-covalent interactions, conditioning the existence of living matter and determining the number of physicochemical properties of various materials. Since the role of FT-IR spectroscopy in the field of hydrogen bond research has great significance, a historical outline of the most important qualitative and quantitative hydrogen bond theories is provided. In addition, research on selected unconventional spectral effects resulting from the substitution of protons with deuterons in hydrogen bridges is presented. The state-of-the-art and originality of the current review are that it presents a combination of uses of FT-IR spectroscopy to explain the way molecules vibrate and the effects of those vibrations on macroscopic properties, hence practical applications of given substances.

Because of their size, small depth, periodic drying out, and often lack of buffer zone, small watercourses are especially sensitive to environmental changes, anthropopressure, and biodegradation which makes them extremely prone to decline in biodiversity. Small watercourses can harbor many species of fish, including alien and invasive species. The objectives of this study were the assessment of environmental conditions, the determination of the number of fish species, their density and diversity in 10 small water courses of the European ecoregion ‘Central Plains’, and to estimate the effect of individual habitat parameters on the ichthyofauna. The total number of fish caught during the study was 9339, representing 33 species. Statistical analyses showed that the density of rheophilous fish was under the effect of flow velocity, discharge, width, depth, oxygen content, and pH; for the limnophilous species, the decisive factors were: discharge, depth, width, and P-PO4. The density of the euryoecious species was affected by depth, pH, electric conductivity (EC), oxygen, as well as N-NO3. All the species were significantly influenced by sandy substratum and the development of aquatic vegetation. Each guild, and even individual species, had their preferred habitat conditions, which is important for water management, renaturisation, and restitution.

Most publications on the influence of environmental factors on macroinvertebrate communities focus on large rivers, whereas relatively few examine small watercourses in agricultural areas, which, due to their size and pressure from intensive agricultural production, are much more susceptible to the effects of unfavourable environmental conditions or anthropopressure. The aim of our study was to compare the biodiversity of macrozoobenthos assemblages and to determine the effects of physicochemical and hydrological conditions on their abundance and density in 10 small rivers in agricultural areas located in northwest (53°23′ N 15°14′ E) and central (52°11′ N 20°48′ E) Poland. In total, 105 taxa were recorded, with the majority being euryoecious. Among the assessed physicochemical parameters, oxygenation was found to affect the density and number of taxa; another important factor was the content of nitrate nitrogen. Sensitivity to changes in water temperature was observed in some macrozoobenthos taxa (especially Decapoda). Of the examined hydrological parameters, the greatest effects were exerted by speed, flow, and depth.

Bifosfoniany należą do silnych inhibitorów osteoklastów. Znajdują szerokie zastosowanie w leczeniu chorób przebiegających ze wzmożoną resorpcją kości: osteoporozy, choroby Pageta i osteogenesis imperfecta. Leki te zmniejszają adhezję komórek nowotworowych do kości, ograniczają osteolizę wywołaną nowotworem i hiper‑ kalcemię. Zmniejszają dolegliwości bólowe w szpiczaku mnogim i w przerzutach do kości. Powszechnie panu‑ jące przekonanie o bezpieczeństwie spowodowało rozszerzenie wskazań do ich stosowania. Pacjenci onkolo‑ giczni przyjmujący bifosfoniany dożylnie, w wysokich dawkach są bardziej narażeni na działania niepożądane terapii niż pacjenci przyjmujący je doustnie. Jednym z najpoważniejszych powikłań jest martwica kości szczęk. W 2003 roku opisano po raz pierwszy związek pomiędzy terapią bifosfonianami a martwicą kości szczęk. W piśmiennictwie znajdujemy coraz więcej przykładów tego działania niepożądanego, także po stosowaniu leków doustnie. Mogą pojawiać się ból, obrzęk, owrzodzenie, odsłonięcie kości, przetoki, złamania patologiczne, uciążliwe dla pacjenta i obniżające jakość życia. Leczenie martwicy kości szczęk jest trudne i rzadko przynosi spodziewany efekt. Główną rolę odgrywa leczenie zachowawcze i redukcja objawów. Odstawienie bifosfonia‑ nów nie ma bezpośredniego wpływu na przebieg martwicy kości szczęk, ze względu na kumulację leku w kości. Istotne jest przygotowanie pacjenta przed rozpoczęciem podawania bifosfonianów, wymagające stałej współ‑ pracy pomiędzy lekarzami onkologami, ortopedami i chirurgami szczękowo-twarzowymi. Higiena jamy ustnej i leczenie chorób współistniejących stanowi ważny element postępowania. Celem pracy jest przedstawienie trzech przypadków martwicy kości szczęk u pacjentów poddanych leczeniu bifosfonianami.

The paper addresses the issues of invoking services from within workflows which are becoming an increasingly popular paradigm of distributed programming. The main idea of our research is to develop a facility which enables load balancing between the available services and their instances. The system consists of three main modules: a proxy generator for a specific service according to its interface type, a proxy that redirects requests to a concrete instance of the service and load-balancer (LB) to choose the least loaded virtual machine (VM) which hosts a single service instance. The proxy generator was implemented as a bean (in compliance to EJB standard) which generates proxy according to the WSDL service interface description using XSLT engine and then deploys it on a GlassFish application server using GlassFish API, the proxy is a BPEL module and load-balancer is a stateful Web Service.