bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of luminal Ca2+on the stability of coupled gating between ryanodine receptors from the rat heart
Authors: Gaburjakova J. , Gaburjakova M. 
Published: February 2008

AbstractAim: Two or more RYR2 channels reconstituted into a bilayer lipid membrane (BLM) can open and close either independently (single gating) or simultaneously (coupled gating). The coupled gating phenomenon has been suggested as an attractive candidate for a termination mechanism of Ca2+release from the sarcoplasmic reticulum, required for periodic contraction and relaxation of cardiac muscle.Methods: Using the method of reconstitution of a channel into the BLM, we investigated the potential effect of luminal Ca2+on the stability of the interaction between coupled RYR2 channels isolated from the rat heart. We introduced a new parameter – the coupling stability – for each detected simultaneous opening and closing and further averaged values for experiments performed under identical conditions.Results: We found that the coupling stability during simultaneous opening of RYR2 channels was significantly lower in comparison with the simultaneous closing under the same experimental conditions. Furthermore, high concentration of luminal Ca2+(53 mmol L−1) as well as the absence of luminal Ca2+noticeably destabilized functional coupling between coupled RYR2 channels during opening, in contrast to lower tested concentrations (8–20 mmol L−1).Conclusions: We provide experimental evidence that the strength of interaction between coupled RYR2 channels depends on the functional state of the channels. Furthermore, we show, for the first time, the regulation role of luminal Ca2+in the inter‐RYR2 functional coupling in the rat heart.
1‐factorization of regular graphs by colour exchange
Authors: Cariolaro David 
Published: February 2008

AbstractWe present a new general theory that deals with the problem of determining a 1‐factorization of a graph using only the elementary technique of colour exchange. Our work is inspired by an old question of Vizing, who in [Cybernetics 3 (1965) 32–41] asked whether an optimal edge colouring of any multigraph G can always be obtained from an arbitrary edge colouring of G by repeatedly exchanging colours along bicoloured chains and suppressing empty colour classes. We conjecture that the answer to Vizing's question is affirmative. We apply our theory to the class of regular graphs of even order at most 10, proving the validity of this conjecture for this class of graphs. This yields an algorithm for finding a 1‐factorization of any 1‐factorizable graph of order at most 10. We also formulate two (stronger) conjectures and prove that they hold for the same class of graphs. Our method can be extended to graphs of larger order and to non‐regular graphs or multigraphs.
Contribution of non-work and work-related risk factors to the association between income and mental disorders in a working population: the Health 2000 Study
Authors: Virtanen M , Koskinen S , Kivimäki M , Honkonen T , Vahtera J , Ahola K , Lönnqvist J 
Published: February 2008

Objectives:To examine the contribution of non-work and work factors to the association between income and DSM-IV depressive and anxiety disorders in a working population.Methods:A representative sample of the Finnish working population aged 30–64 (1667 men, 1707 women) in 2000–2001 responded to a survey questionnaire on non-work factors (marital status, housing conditions, non-work social support, violence victimisation, smoking, physical symptoms), work factors (job demands, job control, social support at work, educational prospects, job insecurity) and household income. Somatic health was examined in a standard health examination. The 12-month prevalence of depressive and anxiety disorders was examined with the Composite International Diagnostic Interview.Results:The risk of having a depressive or anxiety disorder was 2.8 times higher in the low-income group than in the high-income group among men and 2.0 times higher among women. For men, non-work and work factors explained 20% and 31% of this association, respectively. For women, the corresponding figures were 65% and 23%.Conclusions:Low income is associated with frequent mental disorders among a working population. In particular, work factors among men and non-work factors among women contribute to the income differences in mental health.
DIRECTED GRAPHS AND KRONECKER INVARIANTS OF PAIRS OF MATRICES
Authors: TOWBER JACOB 
Published: February 2008

Call two pairs (M,N) and (M′,N′) of m × n matrices over a field K, simultaneously K-equivalent if there exist square invertible matrices S,T over K, with M′ = SMT and N′ = SNT. Kronecker [2] has given a complete set of invariants for simultaneous equivalence of pairs of matrices. Associate in the natural way to a finite directed graph Γ, with v vertices and e edges, an ordered pair (M,N) of e × v matrices of zeros and ones. It is natural to try to compute the Kronecker invariants of such a pair (M,N), particularly since they clearly furnish isomorphism-invariants of Γ. Let us call two graphs "linearly equivalent" when their two corresponding pairs are simultaneously equivalent. There have existed, since 1890, highly effective algorithms for computing the Kronecker invariants of pairs of matrices of the same size over a given field [1,2,5,6] and in particular for those arising in the manner just described from finite directed graphs. The purpose of the present paper, is to compute directly these Kronecker invariants of finite directed graphs, from elementary combinatorial properties of the graphs. A pleasant surprise is that these new invariants are purely rational — indeed, integral, in the sense that the computation needed to decide if two directed graphs are linearly equivalent only involves counting vertices in various finite graphs constructed from each of the given graphs — and does not involve finding the irreducible factorization of a polynomial over K (in apparent contrast both to the familiar invariant-computations of graphs furnished by the eigenvalues of the connection matrix, and to the isomorphism problem for general pairs of matrices).
A DOMAIN TEST FOR LIE COLOR ALGEBRAS
Authors: PRICE KENNETH L. 
Published: February 2008

Lie color algebras are generalizations of Lie superalgebras and graded Lie algebras. The properties of a Lie color algebra can often be related directly to the ring structure of its universal enveloping algebra. We study the effects of torsion elements and torsion subspaces. Let [Formula: see text] denote a Lie color algebra. If [Formula: see text] is homogeneous and torsion then x2 = 0 in [Formula: see text]. If no homogeneous element of [Formula: see text] is torsion, then [Formula: see text] so [Formula: see text] is semiprime. In this case we can give a test which uses Gröbner basis methods to determine when [Formula: see text] is a domain. This is applied in an example to show [Formula: see text] may be a domain even if [Formula: see text] contains torsion elements and torsion subspaces.
Climate change and groundwater: a short review
Authors: Dragoni W. , Sukhija B. S. 
Published: February 2008

Abstract
There is a general consensus that climate change is an ongoing phenomenon. This will inevitably bring about numerous environmental problems, including alterations to the hydrological cycle, which is already heavily influenced by anthropogenic activity. The available climate scenarios indicate areas where rainfall may increase or diminish, but the final outcome with respect to man and environment will, generally, be detrimental. Groundwater will be vital to alleviate some of the worst drought situations. The paper analyses the main methods for studying the relationships between climate change and groundwater, and presents the main areas in which hydrogeological research should focus in order to mitigate the likely impacts.
Application of isotope techniques in groundwater recharge studies in arid western Rajasthan, India: some case studies
Authors: Sinha U. K. , Navada S. V. 
Published: February 2008

Abstract
Environmental isotope studies of groundwaters carried out in the arid region of Rajasthan, India, suggest that recharge to shallow groundwater occurs as a result of direct infiltration of precipitation and/or through river channels during episodic floods. In many parts of Rajasthan deep fresh groundwater is available, which was recharged in the past when the climatic conditions were more favorable than at present. However, negligible modern recharge and over-exploitation of groundwater resources have led to the deterioration of groundwater quality in the Bhadka–Bheemda area of Barmer district. Buried river courses (palaeochannels) could be potential sources of groundwater since radiocarbon measurements of groundwater along palaeochannels in Jaisalmer district revealed that it was old water recharged a few thousand years ago.
A tale of two cities in ancient Canaan: how the groundwater storage capacity of Arad and Jericho decided their history
Authors: Issar A. S. 
Published: February 2008

Abstract
The history of two ancient cities, Arad and Jericho, sheds light on the role of groundwater storage in deciding the survival of settlements in arid and semi-arid regions when climate changes take place. Arad, which was dependent on a local perched horizon, was deserted during the global warm periods, which spelled dryness in the Middle East. This was in spite of one of the earliest systems of artificial recharge to groundwater developed by its inhabitants. On the other hand Jericho, which depended on the supply from a perennial spring, fed by a regional aquifer, was almost continuously settled from prehistoric times to the present.
Impacts of climatic change on water resources: the future of groundwater recharge with reclaimed water in the south of Europe
Authors: Salgot M. , Torrens A. 
Published: February 2008

Abstract
In an era of increasing contest for limited water resources, the wise joint management of conventional and non-conventional water resources must be considered. Water scarcity is aggravated in coastal zones which are often characterized by high population densities and intense economic activities making heavy seasonal water demands. In this context, the use of non-conventional water increases the availability of water supplies. Non-conventional water resources of lower quality could be directed to meet additional needs. As a consequence, significantly more potable water would be available to meet human demand for safe water.
Non-conventional water resources are described: waste water reclamation and reuse, and its potential application for increasing groundwater resources, as well as several practical applications.
Adaptation to climate change: strategies for sustaining groundwater resources during droughts
Authors: Sukhija B. S. 
Published: February 2008

Abstract
Extreme climate conditions are expected in the twenty-first century in the form of higher maximum temperature (with more hot days) resulting in frequent droughts. The continents of Africa and Asia are anticipated to be extremely vulnerable to droughts. In the impending extreme climate conditions, humanity's sustenance hinges on groundwater as it forms the world's largest freshwater resource. Adaptive and mitigation measures entail well planned strategies for sustained groundwater through extreme climate conditions including droughts. In this paper two such strategies are discussed to overcome the problem of droughts: (i) artificial groundwater recharge using percolation ponds; and (ii) identifying and characterizing deep aquifers resilient to droughts through detailed geophysical, hydrogeological and isotopic studies.
Percolation ponds act as artificial recharge structures which are constructed across monsoon streams with the purpose of harvesting surface runoff caused by monsoon streams. Conventional and tracer methods were developed in India to determine how effective these artificial recharge structures could be. From studies carried out on percolation ponds located in diverse geological formations such as granites, basalts and sandstones, it was concluded that these structures are quite useful for overcoming droughts in semi-arid and arid regions, and it was demonstrated that the role of geology outweighs the effect of climate on such structures. It has been shown that in a similar climatic environment, the percolation ponds in sandstones were far more efficient (efficiency 60%) than those in basalts (efficiency 20–30%).

Recently it has been realized that certain deep aquifers can yield a good quantity and quality of water even during extreme climate events. The Neyveli aquifer in southern India has been demonstrated to be such a representative aquifer for mitigation of droughts. Very extensive and intensive hydrogeological and isotopic studies on the aquifer revealed that the aquifer has distinct characteristics, namely: (i) distinct recharge area; (ii) extensive groundwater regime with high degree of recharge rate; (iii) wide span of radiocarbon ages from Modern to >30 000 years
bp
indicating modern as well as palaeorecharge; and (iv) minimal changes in groundwater quality despite very heavy and continuous withdrawal during the last four decades. All these criteria provide the necessary ingredients for drought resilient aquifers which can be used to identify similar aquifers elsewhere in the world.
Some aspects of groundwater regime in Bulgaria with respect to climate variability
Authors: Benderev A. D. , Orehova T. V. , Bojilova E. K. 
Published: February 2008

Abstract
Groundwater regime in Bulgaria is influenced by climate variability. The impact is evident especially for karst water. A time series analysis of spring discharge for selected karst basins was performed. The impact of the 1982–1994 drought period on groundwater regime was detected. For springs that drain open and mountainous karst, the impact of climate variability is similar to that on surface waters. In fact, the difference in degree of influence of the drought period is related to the specific geological structure of the karst massifs and recharge conditions. Furthermore, the porous waters are characterized by a weaker reaction to such an effect. In general, groundwater use during the 1982–1994 drought period was impacted by climate variability due to limited resource availability.
Effects of climate change on groundwater resources in Campania (southern Italy)
Authors: Ducci D. , Tranfaglia G. 
Published: February 2008

Abstract

In order to estimate the influence of global climate change upon the hydrological regime, variations in the water budget prompted by precipitation and temperature changes were evaluated in the region of Campania (southern Italy). In many parts of the region, precipitation distribution in the last 20 years shows a marked reduction. During the same period, Campania also experienced a regional temperature increase of about 0.3°C. Water budgets, calculated in a geographical information system environment for the region's hydrogeological structures, show a mean decrease of 30% of average infiltration within the present climate scenario. The structures most affected are carbonate aquifers, with the flow of springs being significantly reduced (about 70 m
3
/s). The most severely affected zones are the mountainous areas in the southern and northern parts of Campania.
Climate change, drought and groundwater availability in southern Italy
Authors: Polemio M. , Casarano D. 
Published: February 2008

Abstract

Data for the period 1821 to 2003 from 126 rain gauges, 41 temperature gauges, eight river discharge gauges and 239 wells, located in southern Italy, have been analysed to characterize the effect of recent climate change on availability of water resources, focusing on groundwater resources. Regular data are available from 1921 to 2001. Many analysis methods are used: principal component analysis, to divide the study area into homogenous portions; trend analysis, considering the Mann–Kendall, Student-
t
and Craddock tests, autocorrelation and cross-correlation analyses, and seasonal, annual and moving-average variables, applying the spatial analysis to each variable with a geographical information system approach.

A widespread decreasing trend of annual rainfall is observed over 97% of the whole area. The decreasing trend of rainfall worsens or decreases as mean annual rainfall increases; the spatial mean of trend ranges from −0.8 mm/a in Apulia to −2.9 mm/a in Calabria. The decrease in rainfall is notable after 1980: the recent droughts of 1988–1992 and 1999–2001 appear to be exceptional. On a seasonal basis, the decreasing trend is concentrated in winter; a slight positive trend is observed in summer, the arid season in which the increase is useless as it is transformed into actual evapotranspiration. The temperature trend is not significant and homogeneous everywhere if the temperature increase seems to prevail, especially from about 1980. Net rainfall, calculated as a function of monthly rainfall and temperature, shows a huge and generalized negative trend.
The trend of groundwater availability is so negative everywhere that the situation can be termed dramatic for water users, due not only to the natural drop in recharge but also to the increase of discharge by wells to compensate the non-availability of surface water tapped by dams, as a direct effect of droughts.
Climatological cycles in groundwater levels in a detritic aquifer
Authors: Luque-Espinar J. A. , Chica-Olmo M. , Pardo-Igúzquiza E. 
Published: February 2008

Abstract
The spectral analysis of waterhead measurements on a network of piezometers has allowed the analysis of the spatio-temporal variability of data in the Vega de Granada aquifer (southern Spain). This analysis has detected several long-term cycles in the piezometric time series for the period 1966–2001. A complete analysis, using different spectral methods of those time series, has detected four different cycles: a decadal period (11 years), a 3.2-year period, an annual period and a semi-annual period. The annual cycle is ubiquitous, as a reflection of the annual hydrological cycle. The decadal cycle can be traced to hydrological variations involving a climatological regime induced by sunspot activity (11-year cycle). The piezometers located close to streamflows reaching the aquifer or along the main river, in areas where the main river recharges the aquifer, present a statistically significant decadal cycle. The explanation for the presence and spatial distribution of the 3.2-year cycle is similar to the decadal cycle, though it is identified in fewer piezometers.
Yperia Krini spring (central Greece): inferences on climatic changes from its 2000 years of history
Authors: Rapti-Caputo D. , Helly B. 
Published: February 2008

Abstract
The development of past civilizations and the foundation of towns have always been strictly linked to the availability of water. In this paper, we analyse more than 2000 years of evolution of Yperia Krini spring in Thessaly (Greece), by investigating possible variations in terms of water discharge. In particular, the integrated analysis of geological, hydrological, hydrogeological and historical data relative to the spring, called by Sophocles a ‘gift of God and source of life’, allowed us to understand the role played by both climatic variations and anthropogenic activities on the behaviour and the characteristics of the local underground water resources within the Thessalian plain.
Origin of a fresh groundwater body in Cholistan, Thar Desert, Pakistan
Authors: Geyh M. A. , Ploethner D. 
Published: February 2008

Abstract
The Thar Desert of Pakistan stretches along the border to India and is one of the most densely populated deserts in the world. Brackish to saline groundwater prevails. A locally restricted fresh groundwater resource was discovered by a comprehensive hydrogeological, geophysical, and isotope hydrological survey conducted from 1986 to 1991. The origin, recharge mechanism and age of the fresh groundwater resource were assessed. There is only fossil groundwater and this must be mined. Sodium is the predominant cation. Present groundwater recharge is absent or extremely low as the annual precipitation rate and the potential evapotranspiration rate amount to less than 200 mm/a and about 2700 mm/a, respectively. The investigations comprised a hydrogeological well inventory, electrical resistivity transects on the ground and an air-borne electromagnetic survey, followed by a test-hole drilling programme combined with geophysical borehole logging, aquifer testing, and groundwater sampling for both chemical and environmental isotope analyses. The results of this study delivered a hydrogeological concept on the origin and recharge of the fresh groundwater body. We found that the fresh groundwater was indirectly recharged during flash floods in low lands during the last pluvial period rather than directly replenished in the high mountain areas far in the east.
Transient response of groundwater systems to climate changes
Authors: Seiler K.-P. , Gu W.-Z. , Stichler W. 
Published: February 2008

Abstract
Groundwater flow is steered by both the groundwater recharge rate and by discharge altitudes above or below sea level; it is further controlled by the hydraulic properties of the aquifer system and often contains a transient flow component affected by natural hydrologic processes. All present groundwater discharges have both recent (<100 years) and past groundwater recharge components (>100 years). The ratio of the present to the past groundwater recharge depends on the climate zone: it is large in humid and small in arid areas, hence at low recharge rates transient, and at high groundwater recharge rates steady-state conditions prevail. Developing groundwater management strategies while neglecting any transient response of groundwater resources, and conducted in sensitive recharge/discharge areas like dry lands, results in either over-estimates or under-estimates of safe yields of groundwater resources, and thus may lead to non-sustainable resource development. The consequence of this would be groundwater depletion and often also a deterioration of the hydraulic properties of the aquifer system by subsidence, which both take place only after a long period of time.
Effect of an anti-sulfatide single-chain antibody probe on platelet function
Authors: Shrimpton Corie , Honke Koichi , Rumbaut Rolando , Lopez Jose , Thiagarajan Perumal , Guchhait Prasenjit 
Published: February 2008

SummarySulfatide (galactocylceramide-3'-sulfate), a cell surface glycosphingolipid interacts with several cell adhesion molecules including fibrinogen, von Willebrand factor (VWF), P-selectin, thrombospondin (TSP) and laminin, which are involved in haemostasis.We have used a sulfatide-specific single-chain fragment variable (scFv) antibody probe PA38 and sulfatide-deficient mice to investigate the role of membrane sulfatide in platelet function. PA38 bound to platelets and binding increased following platelet activation. Sulfatide was localized as a large cluster towards the center of the platelet surface when examined in a confocal microscope. PA38 (20 μg/ml) inhibited the adhesion of activated platelets to fibrinogen,VWF, P-selectin,TSP1 and laminin by 30%, 30%,75%,20% and 35%,respectively,compared to a control scFv (p<0.05). Furthermore, PA38 inhibited collagen, ADP, thrombin and ristocetin-induced platelet aggregation in PRP by 25%, 30%, 18% and 20%, respectively, compared to the control scFv (p<0.05). In a PFA-100 platelet function assay, PA38 prolonged the occlusion time by 25% (p<0.05).Under flow PA38 decreased the thrombus formation on collagen by 31%, (p<0.01). Sulfatidedeficient mice displayed an extended lag-phase in collagen-induced platelet aggregation compared to wild type (p<0.05), though in-vivo haemostasis did not differ significantly.Thus, this study provides new evidence for a role for membrane sulfatide in platelet function.