bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lake Ladoga ice phenology: Mean condition and extremes during the last 65 years
Authors: Karetnikov Sergey , Naumenko Mikhail 
Published: February 2011

AbstractWinter conditions play an important role for the largest lake in Europe—Lake Ladoga. The ice cover lasts for 171 ± 3 days on average from the early November until the mid‐May. We investigated the ice regime of Lake Ladoga using a constructed ice database of aircraft surveys and satellite images. More than 1250 surveys of the lake's ice cover from 1943 to 2010 were collected and analysed to determine mean and extreme ice conditions for winters of different types of severity. The time series of ice cover percentage over the lake was plotted. On average, 18 observational ice charts were made every winter. Individual ice phenology records show considerable year‐to‐year variation. For this reason, records typically have been combined and analysed as groups (categories). Extremely cold winters were determined as winters with complete ice cover that lasts more than three months which is approximately 90% quartiles from all winters with complete ice cover. The lake surface was completely covered with ice for more than three months during 5 seasons. Extremely warm winters when the maximum ice cover was less than 70% of the lake area occurred during 5 seasons as well. A basic relationship between the winter severity as winter maximum of accumulated freezing degree‐days (AFDD) and the earlier derived Relative Ice Cover Index (RICI) was established. We have used teleconnection indices such as North Atlantic Oscillations (NAO) and Arctic Oscillation (AO) for the period from October to May for estimation of different types of Lake Ladoga's ice conditions. The AO index in winter months and local winter maximum of AFDD explained much of the interannual variation in ice cover. Copyright © 2011 John Wiley & Sons, Ltd.
Changes to sediment sources following wildfire in a forested upland catchment, southeastern Australia
Authors: Smith Hugh G. , Sheridan Gary J. , Lane Patrick N. J. , Noske Philip J. , Heijnis Henk 
Published: February 2011

AbstractFew investigations link post‐fire changes to sediment sources and erosion processes with sediment yield response at the catchment scale. This linkage is essential if downstream impacts on sediment transport after fire are to be understood in the context of fire effects across different forest environments. In this study, we quantify changing source contributions to fine sediment (<63 µm) exported from a eucalypt forest catchment (136 ha) burnt by wildfire. The study catchment is one of a pair of research catchments located in the East Kiewa River valley in southeastern Australia that have been the subject of a research program investigating wildfire effects on runoff, erosion, and catchment sediment/nutrient exports. This previous research provided the opportunity to couple insights gained from a range of measurement techniques with the application of fallout radionuclides 137Cs and 210Pbex to trace sediment sources. It was found that hillslope surface erosion dominated exports throughout the 3·5‐year post‐fire measurement period. During this time there was a pronounced decline in the proportional surface contribution from close to 100% in the first six months to 58% in the fourth year after fire. Over the study period, hillslope surface sources accounted for 93% of the fine sediment yield from the burnt catchment. The largest decline in the hillslope contribution occurred between the first and second years after fire, which corresponded with the previously reported large decline in sediment yield, breakdown of water repellency in burnt soils, substantial reduction in hillslope erodibility, and rapid surface vegetation recovery. Coupling the information on sediment sources with hillslope process measurements indicated that only a small proportion of slopes contributed sediment to the catchment outlet, with material derived from near‐channel areas dominating the post‐fire catchment sediment yield response. Copyright © 2011 John Wiley & Sons, Ltd.
Roles of genipin crosslinking and biomolecule conditioning in collagen‐based biopolymer: Potential for vascular media regeneration
Authors: Madhavan Krishna , Belchenko Dmitry , Tan Wei 
Published: February 2011

AbstractThe vascular media, a layer of the blood vessel wall containing smooth muscle cells (SMCs), are often the target functional tissue in the construction of artificial vessel. It contributes to mechanical properties and biological functions of vessels. The present study aimed to study effects of crosslinking and biomolecule conditions in the development of mechanically strong and stable, biologically functional constructs with potential for vascular media regeneration. Genipin was used to crosslink collagen–chitosan–elastin (CCE) constructs. Results revealed that mechanical strength, stiffness, and stability of CCE constructs significantly increased with genipin concentration, but crosslinking significantly inhibited SMC contraction of and invasion in gel constructs. No contraction or invasion was observed in those crosslinked with genipin at 5 mM or above. attenuated total reflectance Fourier transform infrared results showed crosslinking changed functional groups on CCE depending on genipin concentration. To enhance biological activities on crosslinked constructs, soluble molecule factors were incorporated, and their effects on SMC activities were evaluated. These conditions include heparin, platelet‐derived transforming growth factor (PDGF), high‐concentrated fetal bovine serum (h‐FBS), a mixture of heparin and PDGF, and a mixture of h‐FBS and PDGF. The h‐FBS and PDGF mixture was found to stimulate a 3.2‐fold increase in SMC contraction of the crosslinked gels. It was also found that PDGF and h‐FBS, separately and in combination, induced SMC invasion in the crosslinked gels, while heparin attenuated PDGF‐induced SMC invasion. Our study suggests that designing high‐performance acellular constructs to encourage tissue regeneration should use a combination of crosslinking condition and biomolecule factor, striking a balance between mechanical properties and biological functions. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2011.
The influence of surface energy of titanium‐zirconium alloy on osteoblast cell functions in vitro
Authors: Sista Subhash , Wen Cui'e , Hodgson Peter D. , Pande Gopal 
Published: February 2011

AbstractThe success of an implant used for bone regeneration and repair is determined by the events that take place at the cell–material interface. An understanding of these interactions in vitro gives insights into the formulation of ideal conditions for their effective functioning in vivo. Thus, it is not only important to understand the physico‐chemical properties of the materials but, also necessary to assess the cellular responses to them to determine their long‐term stability and efficacy as implants. In the present study, we have compared the physico‐chemical and biological properties of titanium (Ti) and two Ti‐based alloys, namely: Ti‐ Zirconium (TiZr) and Ti‐Niobium (TiNb). The morphology, chemical analysis, surface roughness, and contact angle measurements of the alloys were assessed by scanning electron microscopy (SEM), X‐ray photoelectron spectroscopy (XPS), profilometer, and contact angle goniometer, respectively whereas the biological properties of the materials were evaluated by measuring the adhesion, proliferation, and differentiation of MC3T3‐E1 osteoblast cells on the surfaces of these alloys. Our results indicate that the biological properties of osteoblasts were better on TiZr surface than on TiNb surface. Furthermore, the surface energy and substrate composition influenced the superior biological activity of the TiZr alloy. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2011.
Structure and properties of biomedical films prepared from aqueous and acidic silk fibroin solutions
Authors: Rajkhowa Rangam , Levin Brett , Redmond Sharon L. , Li Lu Hua , Wang Lijing , Kanwar Jagat R. , Atlas Marcus D. , Wang Xungai 
Published: February 2011

AbstractSilk fibroin films are promising materials for a range of biomedical applications. To understand the effects of casting solvents on film properties, we used water (W), formic acid (FA), and trifluoroacetic acid (TFA) as solvents. We characterized molecular weight, secondary structure, mechanical properties, and degradation behavior of cast films. Significant degradation of fibroin was observed for TFA‐based film compared to W and TA‐based films when analyzed by SDS–PAGE. Fibroin degradation resulted in a significant reduction in tensile strength and modulus of TFA‐based films. Compared to water, TFA‐based films demonstrated lower water solubility (19.6% vs. 62.5% in 12 h) despite having only a marginal increase in their β‐sheet content (26.9% vs. 23.7%). On the other hand, FA‐based films with 34.3% β‐sheet were virtually water insoluble. Following solubility treatment, β‐sheet content in FA‐based films increased to 50.9%. On exposure to protease XIV, water‐annealed FA‐based films lost 74% mass in 22 days compared to only 30% mass loss by ethanol annealed FA films. This study demonstrated that a small variation in the β‐sheet percentage and random coil conformations resulted in a significant change in the rates of enzymatic degradation without alteration to their tensile properties. The film surface roughness changed with the extent of enzymatic hydrolysis. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2011.
Controlled curing of adhesive complex coacervates with reversible periodate carbohydrate complexes
Authors: Shao Hui , Weerasekare G. Mahika , Stewart Russell J. 
Published: February 2011

AbstractPeriodate oxidation of carbohydrates with vicinal hydroxyl groups and aromatic ortho‐dihydroxyphenyl groups has been employed extensively to initiate crosslinking or conjugation reactions in adhesive biomaterials. Periodate forms stable tridentate complexes with carbohydrates containing three appropriately configured hydroxyls, such as 1,2‐O‐isopropylidene‐a‐D‐glucofuranose, that are not appreciably oxidized relative to carbohydrates with vicinal hydroxyls and ortho‐dihydroxyphenyl groups. In the presence of 1,2‐O‐Isopropylidene‐a‐D‐glucofuranose the rate of periodate oxidation of dihydroxy containing compounds is controlled by the rates of association and dissociation of the periodate‐carbohydrate complex. By varying the ratio of 1,2‐O‐isopropylidene‐a‐D‐glucofuranose to periodate the curing rate of adhesive complex coacervates was varied over a wide range. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2011.
Mortality risk for operated and nonoperated vertebral fracture patients in the medicare population
Authors: Edidin Avram Allan , Ong Kevin L , Lau Edmund , Kurtz Steven M 
Published: February 2011

Abstract
Vertebral compression fractures (VCFs) are associated with increased mortality risk, but the association between surgical treatment and survivorship is unclear. We evaluated the mortality risk for VCF patients undergoing conservative treatment (nonoperated), kyphoplasty, and vertebroplasty. Survival of VCF patients in the 100% U.S. Medicare data set (2005–2008) was estimated by the Kaplan-Meier method, and the differences in mortality rates at up to 4 years were assessed by Cox regression (adjusted for comorbidities) between operated and nonoperated patients and between kyphoplasty and vertebroplasty patients. An instrumental variables analysis was used to evaluate mortality-rate difference between kyphoplasty and vertebroplasty patients. A total of 858,978 VCF patients were identified, including 119,253 kyphoplasty patients and 63,693 vertebroplasty patients. At up to 4 years of follow-up, patients in the operated cohort had a higher adjusted survival rate of 60.8% compared with 50.0% for patients in the nonoperated cohort (p &lt; .001) and were 37% less likely to die [adjusted hazard ratio (HR) = 0.63, p &lt; .001]. The adjusted survival rates for VCF patients following vertebroplasty or kyphoplasty were 57.3% and 62.8%, respectively (p &lt; .001). The relative risk of mortality for kyphoplasty patients was 23% lower than that for vertebroplasty patients (adjusted HR = 0.77, p &lt; .001). Using physician preference as an instrument, the absolute difference in the adjusted survival rate at 3 years was 7.29% higher in patients receiving kyphoplasty than vertebroplasty (p &lt; .001), compared with a crude absolute rate difference of 5.09%. This study established the mortality risk associated with VCFs diagnosed between 2005 and 2008 with respect to different treatment modalities for elderly patients in the entire Medicare population. © 2011 American Society for Bone and Mineral Research.
Regulation of RANKL-induced osteoclastogenesis by TGF-β through molecular interaction between Smad3 and Traf6
Authors: Yasui Tetsuro , Kadono Yuho , Nakamura Masaki , Oshima Yasushi , Matsumoto Takumi , Masuda Hironari , Hirose Jun , Omata Yasunori , Yasuda Hisataka , Imamura Takeshi , Nakamura Kozo , Tanaka Sakae 
Published: February 2011

Abstract
Previous studies have shown that transforming growth factor β (TGF-β) promotes receptor activator of nuclear factor-κB ligand (RANKL)–induced osteoclastogenesis. However, the underlying molecular mechanisms have not been elucidated. When TGF-β signals were blocked either by a specific inhibitor of TGF-β type 1 receptor kinase activity, SB431542, or by introducing a dominant-negative mutant of TGF-β type 2 receptor, RANKL-induced osteoclastogenesis was almost completely suppressed. Blockade of Smad signaling by overexpression of Smad7 or c-Ski markedly suppressed RANKL-induced osteoclastogenesis, and retroviral induction of an activated mutant of Smad2 or Smad3 reversed the inhibitory effect of SB431542. Immunoprecipitation analysis revealed that Smad2/3 directly associates with the TRAF6-TAB1-TAK1 molecular complex, which is generated in response to RANKL stimulation and plays an essential role in osteoclast differentiation. TRAF6-TAB1-TAK1 complex formation was not observed when TGF-β signaling was blocked. Analysis using deletion mutants revealed that the MH2 domain of Smad3 is necessary for TRAF6-TAB1-TAK1 complex formation, downstream signal transduction, and osteoclast formation. In addition, gene silencing of Smad3 in osteoclast precursors markedly suppressed RANKL-induced osteoclast differentiation. In summary, TGF-β is indispensable in RANKL-induced osteoclastogenesis, and the binding of Smad3 to the TRAF6-TAB1-TAK1 complex is crucial for RANKL-induced osteoclastogenic signaling. © 2011 American Society for Bone and Mineral Research.
Mangiferin: A xanthone attenuates mercury chloride induced cytotoxicity and genotoxicity in HepG2 cells
Authors: Kaivalya Mudholkar , Rao B. Nageshwar , Satish Rao B. S. 
Published: February 2011

AbstractMangiferin (MGN), a dietary C‐glucosylxanthone present in Mangifera indica, is known to possess a spectrum of beneficial pharmacological properties. This study demonstrates antigenotoxic potential of MGN against mercuric chloride (HgCl2) induced genotoxicity in HepG2 cell line. Treatment of HepG2 cells with various concentrations of HgCl2 for 3 h caused a dose‐dependent increase in micronuclei frequency and elevation in DNA strand breaks (olive tail moment and tail DNA). Pretreatment with MGN significantly (p < 0.01) inhibited HgCl2‐induced (20 µM for 30 h) DNA damage. An optimal antigenotoxic effect of MGN, both in micronuclei and comet assay, was observed at a concentration of 50 µM. Furthermore, HepG2 cells treated with various concentrations of HgCl2 resulted in a dose‐dependent increase in the dichlorofluorescein fluorescence, indicating an increase in the generation of reactive oxygen species (ROS). However, MGN by itself failed to generate ROS at a concentration of 50 µM, whereas it could significantly decrease HgCl2‐induced ROS. Our study clearly demonstrates that MGN pretreatment reduced the HgCl2‐induced DNA damage in HepG2 cells, thus demonstrating the genoprotective potential of MGN, which is mediated mainly by the inhibition of oxidative stress. © 2011 Wiley Periodicals, Inc. J Biochem Mol Toxicol 25:108–116 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/jbt.20366
Study on the binding of cerium to bovine serum albumin
Authors: Yuan Dong , Shen Zhonglan , Liu Rutao , Chi Zhenxing , Zhu Jianhua 
Published: February 2011

AbstractThe interaction of Ce3+ to bovine serum albumin (BSA) has been investigated mainly by fluorescence spectra, UV–vis absorption spectra, and circular dichroism (CD) under simulative physiological conditions. Fluorescence data revealed that the quenching mechanism of BSA by Ce3+ was a static quenching process, the binding constant is 6.70 × 105, and the number of binding site is 1. The thermodynamic parameters (ΔH = −29.94 kJ mol−1, ΔG = −32.38 kJ mol−1, and ΔS = 8.05 J mol−1 K−1) indicate that electrostatic effect between the protein and the Ce3+ is the main binding force. In addition, UV–vis, CD, and synchronous fluorescence results showed that the addition of Ce3+ changed the conformation of BSA. © 2011 Wiley Periodicals, Inc. J Biochem Mol Toxicol 25:263–268, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/jbt.20385
Trans fat diet causes decreased brood size and shortened lifespan in Caenorhabditis elegans delta‐6‐desaturase mutant fat‐3
Authors: Reisner Kaja , Lehtonen Marko , Storvik Markus , Jantson Tanel , Lakso Merja , Callaway J. C. , Wong Garry 
Published: February 2011

AbstractTrans‐fatty acids (TFAs) enter the diet through industrial processes and can cause adverse human health effects. The present study was aimed to examine the effects of dietary cis‐ and trans‐fatty acids on the model organism Caenorhabditis elegans. Cis‐ or trans‐18:1n9 triglycerides (25 μM) caused no apparent changes in the numbers of viable progeny of wild‐type N2 animals. However, in fat‐3 mutants lacking delta‐6‐desaturase, the trans‐isomer caused modest decreases in lifespan and progeny after three generations. Long‐chain polyunsaturated fatty acids (PUFA) profiles were significantly altered in fat‐3 mutants compared to wild type but were not altered after exposure to dietary cis‐ or trans‐18:1n9. Genome‐wide expression analysis of fat‐3 mutants revealed hundreds of changes. Several genes involved in fat metabolism (acs‐2, fat‐7, mdt‐15) were significantly increased by cis‐ or trans‐18:1n9 without discrimination between isomers. These results provide support for the hypothesis that dietary trans fats are detrimental to development and aging. © 2011 Wiley Periodicals, Inc. J Biochem Mol Toxicol 25:269–279, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/jbt.20386
Self‐dual and self‐petrie‐dual regular maps
Authors: Richter R. Bruce , Širáň Jozef , Wang Yan 
Published: February 2011

AbstractRegular maps are cellular decompositions of surfaces with the “highest level of symmetry”, not necessarily orientation‐preserving. Such maps can be identified with three‐generator presentations of groups G of the form G = 〈a, b, c|a2 = b2 = c2 = (ab)k = (bc)m = (ca)2 = … = 1〉; the positive integers k and m are the face length and the vertex degree of the map. A regular map (G;a, b, c) is self‐dual if the assignment b↦b, c↦a and a↦c extends to an automorphism of G, and self‐Petrie‐dual if G admits an automorphism fixing b and c and interchanging a with ca. In this note we show that for infinitely many numbers k there exist finite, self‐dual and self‐Petrie‐dual regular maps of vertex degree and face length equal to k. We also prove that no such map with odd vertex degree is a normal Cayley map. Copyright © 2011 Wiley Periodicals, Inc. J Graph Theory 69:152‐159, 2012
Large components in r‐edge‐colorings of Kn have diameter at most five
Authors: Ruszinkó Miklós 
Published: February 2011

AbstractReflecting on problems posed by Gyárfás [Ramsey Theory Yesterday, Today and Tomorrow, Birkhäuser, Basel, 2010, pp. 77–96] and Mubayi [Electron J Combin 9 (2002), #R42], we show in this note that every r‐edge‐coloring of Kn contains a monochromatic component of diameter at most five on at least n/(r−1) vertices. Copyright © 2011 Wiley Periodicals, Inc. J Graph Theory 69:
337–340, 2012
Combinatorial interpretations for TG(1, −1)
Authors: Ma Jun , Yeh Yeong‐Nan 
Published: February 2011

AbstractLet G be a connected and simple graph with vertex set {1, 2, …, n + 1} and TG(x, y) the Tutte polynomial of G. In this paper, we give combinatorial interpretations for TG(1, −1). In particular, we give the definitions of even spanning tree and left spanning tree. We prove TG(1, −1) is the number of even‐left spanning trees of G. We associate a permutation with a spanning forest of G and give the definition of odd G‐permutations. We show TG(1, −1) is the number of odd G‐permutations. We give a bijection from the set of odd Kn + 1‐permutations to the set of alternating permutations on the set {1, 2, …, n}. Copyright © 2011 Wiley Periodicals, Inc. J Graph Theory 69: 341–348, 2012
On the number of triangular embeddings of complete graphs and complete tripartite graphs
Authors: Grannell M. J. , Knor M. 
Published: February 2011

AbstractWe prove that for every prime numberpand oddm>1, ass→∞, there are at leastwface 2‐colorable triangular embeddings ofKw, w, w, wherew=m·ps. For both orientable and nonorientable embeddings, this result implies that for infinitely many infinite families ofz, there is a constantc>0 for which there are at leastznonisomorphic face 2‐colorable triangular embeddings ofKz. © 2011 Wiley Periodicals, Inc. J Graph Theory
Group connectivity of complementary graphs
Authors: Hou Xinmin , Lai Hong‐Jian , Li Ping , Zhang Cun‐Quan 
Published: February 2011

AbstractLet G be a 2‐edge‐connected undirected graph, A be an (additive) abelian group and A* = A−{0}. A graph G is A‐connected if G has an orientation D(G) such that for every function b: V(G)↦A satisfying , there is a function f: E(G)↦A* such that for each vertex v∈V(G), the total amount of f values on the edges directed out from v minus the total amount of f values on the edges directed into v equals b(v). For a 2‐edge‐connected graph G, define Λg(G) = min{k: for any abelian group A with |A|⩾k, G is A‐connected }. In this article, we prove the following Ramsey type results on group connectivity:

Let G be a simple graph on n⩾6 vertices. If min{δ(G), δ(Gc)}⩾2, then either Λg(G)⩽4, or Λg(Gc)⩽4.
Let Z3 denote the cyclic group of order 3, and G be a simple graph on n⩾44 vertices. If min{δ(G), δ(Gc)}⩾4, then either G is Z3‐connected, or Gc is Z3‐connected. © 2011 Wiley Periodicals, Inc. J Graph Theory
Synthesis and antibacterial activity of isochromene and isoquinoline derivative
Authors: Dabholkar Vijay V. , Tripathi Dilip R. 
Published: February 2011

AbstractSynthesis of 4‐thioureidobenzoic acid (2), which on cyclization with ethyl chloroacetate gave 4‐(2‐imino‐5‐oxothiazolidin‐3‐yl)‐benzoic acid (3), which on further reacting with benzoin (4) in the presence of polyphosphoric acid afforded the synthesis of 2‐imino‐3‐(‐1‐oxo‐3,4‐diphenyl‐1H‐isochromen‐6‐yl) thiazolidin‐5‐one (5). Compound 5 was then reacted with substituted anilines to give 6‐(2‐imino‐5‐oxothiazolidin‐3‐yl)‐3,4‐diphenyl‐2‐(substituted)‐isoquinolin‐1(2H)‐one (6). The structures of the compounds have been elucidated on the basis of IR 1HNMR, 13C NMR, and elemental analysis. Representative samples were screened for their antimicrobial activity against gram‐negative bacteria, E. coli and P. aeruginosa and gram‐positive bacteria, S. aureus, and C. diphtheriae using disc diffusion method. J. Heterocyclic Chem., (2011).