Accelerating retreat and high-elevation thinning of glaciers in central Spitsbergen

Svalbard is a heavily glacier-covered archipelago in the Arctic. Dickson Land (DL), in the central part of the largest island, Spitsbergen, is relatively arid, and as a result, glaciers there are relatively small and restricted mostly to valleys and cirques. This study presents a comprehensive analysis of glacier changes in DL based on inventories compiled from topographic maps and digital elevation models for the Little Ice Age maximum (LIA), the 1960s, 1990 and 2009/11. Total glacier area decreased by ~38 % since the LIA maximum, and front retreat has increased over the study period. Recently, most of the local glaciers have been consistently thinning in all elevation bands, in contrast to larger Svalbard ice masses which remain closer to balance. The mean 1990–2009/11 geodetic mass balance of glaciers in DL is among the most negative from the Svalbard regional means known from the literature

Some comments on the flow velocity and thinning of Svenbreen, Dickson Land, Svalbard

In this study a differential GPS survey of flow velocity and surface elevation change of a small glacier Svenbreen, central Svalbard, is presented and discussed. The maximum measured velocity was 3.21 m a-1 at 463 m a.s.l., close the theoretical steady-state equilibrium line altitude. After decades of thinning known from earlier research, the glacier surface has been continuing to lower over the analysed time span 2010-2012 by 1.82 m a-1 at the front at 185 m a.s.l. and 0.08 m a-1 at 541 m a.s.l. Since the glacier dynamics is very low, the study concludes that negative mass balance is the main driver of negative geometry changes and that no new distinct landforms will be formed in the near-future in the glacier forefield

Glacio−meteorology of Ebbabreen, Dickson Land, central Svalbard, during 2008–2010 melt seasons

Interior of Svalbard, High Arctic, is relatively arid and warm during the summer, but impact of this quasi-continental climate type on the glacio-meteorology, surface energy balance and melt processes has been seldom researched. This study brings new data from a weather station located on the largest glacier in Dickson Land, Ebbabreen, at 550 m a.s.l from July and August 2008-2010. The paper discusses air temperature and moisture, wind speed, incoming shortwave radiation and estimates of turbulent heat exchange of the melting surface in the background of atmospheric circulation over Svalbard. The results have shown that average insolation in the study area was low with ca. 135 W m-2. Frequent occurrence of strongly negative temperature gradients resulted in mean July-August air temperature of 1.9°C at the measuring site. Relatively low air vapour pressure led to negative latent heat flux, particularly during advection of air masses from the northern and north-eastern sector. The local microclimate supports the sensible heat transfer, which reached its maximum during eastern circulation situations.This work was sponsored by the Polish Ministry of Higher Education (grant NN 305 098835) and the Polish National Science Centre (grant NN 306 092640)

Variability of summer meteorological and biometeorological conditions in the Ebba Valley region (Central Spitsbergen)

Variability of summer meteorological and biometeorological conditions on the topoclimatic scale in the 2008–2010 summer season in the Ebba Valley region (Central Spitsbergen) was investigated. Three measurement sites, representing different altitudes and topography, as well as different types of active surfaces typical of Spitsbergen, were chosen, where automatic, hourly recorded, measurements were taken. The mean diurnal course of the basic meteorological and biometeorological parameters (i.e. air surface temperature, relative humidity, wind speed and wind direction, global solar radiation, wind chill temperature, cooling power, etc.), was computed for each of the three sites, which demonstrated spatial and temporal variability of biometeorological and weather conditions. Furthermore, four relevant weather types which may appear in the summer in different environments represented by the three measurement sites were distinguished. They can be defined as follows: type 1 – cold and windy weather, type 2 – cold and wet weather, type 3 – sunny weather (moderately windy and relatively warm), type 4 – warm and cloudy weather. The characteristics and occurrence of each of these types were described.517211Badania Fizjograficzn

Synthesis and Electrochemical and Spectroscopic Characterization of 4,7-diamino- 1,10-phenanthrolines and Their Precursors

New approaches to the synthesis of 4,7-dichloro-1,10-phenanthrolines and their corresponding 9H-carbazol-9-yl-, 10H-phenothiazin-10-yl- and pyrrolidin-1-yl derivatives were developed. Their properties have been characterized by a combination of several techniques: MS, HRMS, GC-MS, electronic absorption spectroscopy and multinuclear NMR in both solution and solid state including 15N CP/MAS NMR. The structures of 5-fluoro-2,9-dimethyl-4,7-di(pyrrolidin- 1-yl)-1,10-phenanthroline (5d), 4,7-di(9H-carbazol-9-yl)-9-oxo-9,10-dihydro-1,10-phenanthroline-5- carbonitrile (6a) and 4,7-di(10H-phenothiazin-10-yl)-1,10-phenanthroline-5-carbonitrile (6b) were determined by single-crystal X-ray diffraction measurements. The nucleophilic substitutions of hydrogen followed by oxidation produced compounds 6a and 6b. The electrochemical properties of selected 1,10-phenanthrolines were investigated using cyclic voltammetry and compared with commercially available reference 1,10-phenanthrolin-5-amine (5l). The spatial distribution of frontier molecular orbitals of the selected compounds has been calculated by density functional theory (DFT). It was shown that potentials of reduction and oxidation were in consistence with the level of HOMO and LUMO energies

A role of Pro115Gln mutation in the PPARg gene in the pathogenesis of obesity in a population of Małopolska region

WSTĘP. PPARg (peroxisome - proliferator activated receptor g) jest receptorem jądrowym aktywowanym przez czynniki wywołujące proliferację peroksysomów, w tym przez naturalnie występujące kwasy tłuszczowe i ich pochodne. Jego funkcją jest między innymi regulowanie dojrzewania adipocytów i spichrzania w nich triglicerydów. Mutacje i polimorfizmy tego genu wpływają na powstawanie otyłości i cukrzycy typu 2 u ludzi. Mutacją zmiany sensu, opisaną w populacji niemieckiej, odpowiedzialną za zwiększenie aktywności transkrypcyjnej białka PPARg i powstanie monogenowej formy otyłości jest substytucja proliny przez glutaminę w pozycji aminokwasowej 115 (Pro115Gln). CEL PRACY. Celem badania jest ocena roli mutacji Pro115Gln w powstawaniu ciężkiej otyłości w populacji Małopolski.   MATERIAŁ I METODY. Badanie objęło grupę 89 otyłych osób (60 kobiet i 29 mężczyzn) ze wskaźnikiem masy ciała (BMI, body mass index) większym lub równym 35. Wśród badanych było 64 chorych na cukrzycę typu 2 (43 kobiety, 21 mężczyzn). DNA osób włączonych do badania użyto do namnożenia za pomocą polimerazowej reakcji łańcuchowej (PCR, polymerase chain reaction) fragmentu genu PPARg o długości 129 bp, potencjalnie zawierającego badaną mutację. Mutacji poszukiwano za pomocą techniki zmiennej długości fragmentów restrykcyjnych (RFLP, restriction fragment lenght polymorhism) przy użyciu enzymu restrykcyjnego Hinc II. WYNIKI. W rezultacie przeprowadzonych eksperymentów u żadnej z badanych osób nie stwierdzono obecności miejsca restrykcyjnego dla enzymu Hinc II, a zatem żadna z nich nie była nosicielem poszukiwanej mutacji. Aby uzyskać kontrolę aktywności restrykcyjnej enzymu Hinc II, namnożono fragment genu receptora 4 melanokortyny (MC4R, melanocortin- 4 receptor), zawierający kodon 103, wykazujący polimorfizm walina ® izoleucyna i zastosowano trawienie enzymem Hinc II. WNIOSKI. Z przeprowadzonych badań wynika, że mutacja Pro115Gln w genie PPARg nie jest częstą przyczyną ciężkiej otyłości w populacji Małopolski.INTRODUCTION. PPARg is a nuclear receptor that is activated by factors, fatty acids for example, that influence the activation of peroxisomes. Its function is, among others, the regulation of adipocyte differentiation and trigliceryde storage. Mutations and polymorphisms of this gene influence the pathogenesis of obesity and type 2 diabetes mellitus in humans. Recently, a substitution of proline by glutamine at residue 115 of the PPARg gene has been described in a German population. This Pro115Gln missence mutation caused increased transcriptional activity of the protein and occurrence of monogenic form of obesity. AIM OF STUDY. In the current study we aimed to identify the role of Pro115Gln mutation in the pathogenesis of severe obesity in Małopolska region. MATERIAL AND METHODS. We included into this study 89 obese individuals with BMI (body mass index) equal or above 35 (60 women and 29 men). There were 64 type 2 diabetes patients among them (43 women and 21 men). DNA of these 89 individuals was used to amplify, through polymerase chain reaction (PCR), a 129 base pair DNA fragment that could potentially contain the examined mutation. Screening for the Pro114Gln mutation was performed by restriction fragment length polymorphism (RFLP) method using Hinc II restriction enzyme. RESULTS. None of the examined samples showed the presence of Hinc II restriction site. This constitutes the evidence that our study group did not contain a carrier of the Pro115Gln mutation. To confirm the activity of the Hinc II restriction enzyme used in the study we amplified and digested the fragment of melanocortine 4 receptor gene (MC4R) that contained Val103Ile polymorphism creating Hinc II restriction site. CONCLUSION. Our study proves that Pro115Gln mutation of the PPARg gene is not a frequent cause of severe obesity in a population of Małopolska region

Direct amination of nitroquinoline derivatives via nucleophilic displacement of aromatic hydrogen

The vicarious nucleophilic substitution of hydrogen (VNS) reaction in electron-deficient nitroquinolines was studied. Properties of all new products have been characterized by several techniques: MS, HRMS, FTIR, GC-MS, electronic absorption spectroscopy, and multinuclear NMR. The structures of 4-chloro-8-nitroquinoline, 8-(tert-butyl)-2-methyl-5-nitroquinoline, 9-(8-nitroquinolin-7-yl)-9H-carbazole and (Z)-7-(9H-carbazol-9-yl)-8-(hydroxyimino)quinolin-5(8H)-one were determined by single-crystal X-ray diffraction measurements. The 9-(8-nitroquinolin-7-yl)-9H-carbazole and (Z)-7-(9H-carbazol-9-yl)-8-(hydroxyimino)quinolin-5(8H)-one illustrate the nitro/nitroso conversion within VNS reaction. Additionally, 9-(8-isopropyl-2-((8-isopropyl-2-methyl-5-nitroquinolin-6-yl)methyl)-5-nitrosoquinolin-6-yl)-9H-carbazole is presented as a double VNS product. It is postulated that the potassium counterion interacts with the oxygen on the nitro group, which could influence nucleophile attack in that way

The role of glucagon-like peptide 1-receptor gene in type 2 diabetes

WSTĘP. Celem badania było poszukiwanie związku między polimorfizmami Gly168Ser i Leu260Phe genu receptora glukagonopodobnego peptydu-1 z cukrzycą typu 2 w populacji polskiej. MATERIAŁ I METODY. Analizowano materiał genetyczny 462 chorych na cukrzycę typu 2 i 428 zdrowych ochotników. Genotypowanie polimorfizmów wykonywano, namnażając odpowiednie fragmenty DNA za pomocą reakcji łańcuchowej polimerazy, tnąc namnożone fragmenty enzymami restrykcyjnymi i uwidaczniając produkty cięcia na żelu agarozowym z dodatkiem bromku etydyny. Analiza statystyczna obejmowała test c2 dla zbadania zależności genotypów z chorobą i regresję logistyczną dla zbadania zależności haplotypów z chorobą. WYNIKI. Częstość homozygot Ser/Ser była znamiennie wyższa w grupie chorych na cukrzycę (15,7%) niż w grupie kontrolnej (9,8%), p = 0,03. Iloraz szans rozwoju cukrzycy u tych pacjentów wskazywał na niemal 2-krotnie wyższe ryzyko niż u pacjentów niebędących homozygotami Ser/Ser. Polimorfizm w pozycji 260 oraz haplotypy utworzone przez dwa badane polimorfizmy nie były związane z występowaniem cukrzycy typu 2. WNIOSKI. Wyniki badania sugerują, że polimorfizm Gly168Ser jest potencjalnym czynnikiem ryzyka cukrzycy typu 2 w populacji polskiej. Obserwacja ta wymaga potwierdzenia w innych grupach etnicznych.INTRODUCTION. The aim of the study was to search for the association between Gly168Ser and Leu260Phe amino acid variants of the glucagon-like peptide 1 receptor gene and type 2 diabetes in a Polish population. METHODS. 462 patients with type 2 diabetes and 428 healthy volunteers were genotyped by restriction fragments length polymorphism method after amplification of examined genome fragment by polymerase chain reaction technique. The digestion products were separated and visualized by electrophoresis on agarose gel containing ethidium bromide. Statistical analysis involved chi-square test for genotype-phenotype association and logistic regression for association of phenotype with haplotypes. RESULTS. Ser/Ser homozygotes frequency in diabetic patients group was significantly higher than in control group (15.7% vs. 9.8%, p = 0,03). Odds ratio of having type 2 diabetes in Ser/Ser carriers group versus other genotype carriers showed almost two fold risk increase associated with this genotype. Polymorphism in 260 amino acid position and haplotypes of the analyzed polymorphisms were not associated with type 2 diabetes. CONCLUSIONS. The results of the study suggest that polymorphism Gly168Ser may be potentially a risk factor of the type 2 diabetes in Polish population. This observation should be evaluated in other ethnic groups

The role of glucagon-like peptide 1-receptor gene in type 2 diabetes

WSTĘP. Celem badania było poszukiwanie związku między polimorfizmami Gly168Ser i Leu260Phe genu receptora glukagonopodobnego peptydu-1 z cukrzycą typu 2 w populacji polskiej. MATERIAŁ I METODY. Analizowano materiał genetyczny 462 chorych na cukrzycę typu 2 i 428 zdrowych ochotników. Genotypowanie polimorfizmów wykonywano, namnażając odpowiednie fragmenty DNA za pomocą reakcji łańcuchowej polimerazy, tnąc namnożone fragmenty enzymami restrykcyjnymi i uwidaczniając produkty cięcia na żelu agarozowym z dodatkiem bromku etydyny. Analiza statystyczna obejmowała test χ2 dla zbadania zależności genotypów z chorobą i regresję logistyczną dla zbadania zależności haplotypów z chorobą. WYNIKI. Częstość homozygot Ser/Ser była znamiennie wyższa w grupie chorych na cukrzycę (15,7%) niż w grupie kontrolnej (9,8%), p = 0,03. Iloraz szans rozwoju cukrzycy u tych pacjentów wskazywał na niemal 2-krotnie wyższe ryzyko niż u pacjentów niebędących homozygotami Ser/Ser. Polimorfizm w popozycji 260 oraz haplotypy utworzone przez dwa badane polimorfizmy nie były związane z występowaniem cukrzycy typu 2. WNIOSKI. Wyniki badania sugerują, że polimorfizm Gly168Ser jest potencjalnym czynnikiem ryzyka cukrzycy typu 2 w populacji polskiej. Obserwacja ta wymaga potwierdzenia w innych grupach etnicznych.INTRODUCTION. The aim of the study was to search for the association between Gly168Ser and Leu260Phe amino acid variants of the glucagon-like peptide 1 receptor gene and type 2 diabetes in a Polish population. METHODS. 462 patients with type 2 diabetes and 428 healthy volunteers were genotyped by restriction fragments length polymorphism method after amplification of examined genome fragment by polymerase chain reaction technique. The digestion products were separated and visualized by electrophoresis on agarose gel containing ethidium bromide. Statistical analysis involved chi-square test for genotype-phenotype association and logistic regression for association of phenotype with haplotypes. RESULTS. Ser/Ser homozygotes frequency in diabetic patients group was significantly higher than in control group (15.7% vs. 9.8%, p = 0,03). Odds ratio of having type 2 diabetes in Ser/Ser carriers group versus other genotype carriers showed almost two fold risk increase associated with this genotype. Polymorphism in 260 amino acid position and haplotypes of the analyzed polymorphisms were not associated with type 2 diabetes. CONCLUSIONS. The results of the study suggest that polymorphism Gly168Ser may be potentially a risk factor of the type 2 diabetes in Polish population. This observation should be evaluated in other ethnic groups