bluuebunny/crossref_metadata_2025_split huggingface dataset:
Arsenic, Cadmium, and Lead in California Cropland Soils: Role of Phosphate and Micronutrient Fertilizers
Authors: Chen Weiping , Krage Natalie , Wu Laosheng , Pan Genxing , Khosrivafard Maryam , Chang Andrew C. 
Published: February 2008

AbstractPhosphate and micronutrient fertilizers contain potentially harmful trace elements, such as arsenic (As), cadmium (Cd), and lead (Pb). We investigated if application of these fertilizer increases the As, Cd, and Pb concentrations of the receiving soils. More than 1000 soil samples were collected in seven major vegetable production regions across California. Benchmark soils (no or low fertilizer input) sampled in 1967 and re‐sampled in 2001 served as a baseline. Soils were analyzed for total concentrations of As, Cd, Pb, P, and Zn. The P and Zn concentrations of the soils were indicators of P fertilizer and micronutrient inputs, respectively. Results showed that the concentrations of these elements in the vegetable production fields in some production areas of California had been shifted upward. Principal component analysis and cluster analysis showed that the seven production areas could be sorted into three categories: (i) enrichment of As, Cd, and Pb, which was associated with the enrichment of P and Zn in one of the seven areas surveyed; (ii) enrichment of As, which was associated with enrichment of Zn in two of the seven areas surveyed; and (iii) no remarkable correlation between enrichment of As, Cd, and Pb and enrichment of P and Zn in the other four areas surveyed.
Some insights in the effect of growing bio-energy demand on global food security and natural resources
Authors: Müller Alexander , Schmidhuber Josef , Hoogeveen Jippe , Steduto Pasquale 
Published: February 2008

Growing crops for biofuels is often criticized because of its direct competition for land for food production. The recent price increases on world food markets are partly a result of this competition. For instance, cereals prices have increased by more than 60% since 2005 and in 2006 sugar prices peaked at a level twice as high as the level of previous years. There are concerns whether these increases will continue and if the world will run out of resources for food production. According to the authors, these concerns are largely unwarranted. For one, higher prices for food also mean that feedstocks are becoming increasingly expensive for bio-energy production and this endogenously limits the amount of feedstocks that will be used in the energy market. In addition, there is no imminent global resource shortage, neither for land nor for water that would support these concerns. Even with an expanding world population there is globally still enough land and water to grow a substantial amount of biomass for both food and bio-energy production. However, there is an uneven distribution of natural resources, resulting in huge regional differences with important areas experiencing major land and water shortages. China and India, for example, account together for more than 35% of the total global population and both have exploited most of the land and water resources available for agriculture. On the other hand, sub-Saharan Africa and South America still have the potential, in terms of suitable land and exploitable water, to expand areas for agricultural production.
The growing demand for bio-energy will have a negative and positive effect on food. Higher food prices can increase food insecurity among the urban poor and the rural landless population. On the other hand higher prices and more marketable production can stimulate the agricultural sector and create new opportunities for rural communities. At the national level it can offer development opportunities for countries with significant resources.
Kähler manifolds of quasi-constant holomorphic sectional curvatures
Authors: Ganchev Georgi , Mihova Vesselka 
Published: February 2008

Abstract
The Kähler manifolds of quasi-constant holomorphic sectional curvatures are introduced as Kähler manifolds with complex distribution of codimension two, whose holomorphic sectional curvature only depends on the corresponding point and the geometric angle, associated with the section. A curvature identity characterizing such manifolds is found. The biconformal group of transformations whose elements transform Kähler metrics into Kähler ones is introduced and biconformal tensor invariants are obtained. This makes it possible to classify the manifolds under consideration locally. The class of locally biconformal flat Kähler metrics is shown to be exactly the class of Kähler metrics whose potential function is only a function of the distance from the origin in ℂn. Finally we show that any rotational even dimensional hypersurface carries locally a natural Kähler structure which is of quasi-constant holomorphic sectional curvatures.
Limit theorems in free probability theory II
Authors: Chistyakov Gennadii , Götze Friedrich 
Published: February 2008

Abstract
Based on an analytical approach to the definition of multiplicative free convolution on probability measures on the nonnegative line ℝ+ and on the unit circle $$
\mathbb{T}
$$ we prove analogs of limit theorems for nonidentically distributed random variables in classical Probability Theory.
Spectra of partial integral operators with a kernel of three variables
Authors: Eshkabilov Yusup 
Published: February 2008

Abstract
Let Ω= [a, b] × [c, d] and T
1, T
2 be partial integral operators in $$
C
$$(Ω): (T
1
f)(x, y) = $$
\mathop \smallint \limits_a^b
$$
k
1(x, s, y)f(s, y)ds, (T
2
f)(x, y) = $$
\mathop \smallint \limits_c^d
$$
k
2(x, ts, y)f(t, y)dt where k
1 and k
2 are continuous functions on [a, b] × Ω and Ω × [c, d], respectively. In this paper, concepts of determinants and minors of operators E−τT
1, τ ∈ ℂ and E−τT
2, τ ∈ ℂ are introduced as continuous functions on [a, b] and [c, d], respectively. Here E is the identical operator in C(Ω). In addition, Theorems on the spectra of bounded operators T
1, T
2, and T = T
1 + T
2 are proved.
Titanium‐Catalyzed Enantioselective Synthesis of α‐Ambrinol
Authors: Justicia José , Campaña Araceli G. , Bazdi Btissam , Robles Rafael , Cuerva Juan M. , Oltra J. Enrique 
Published: February 2008

AbstractWe describe the first enantioselective synthesis of the odorant compound (−)‐α‐ambrinol (96% ee) from commercial geranylacetone. The key steps are a Jacobsen’s asymmetric epoxidation and a titanium‐catalyzed stereoselective cyclization initiated by radical epoxide opening. The oxirane ring opening proceeds with retention of configuration at the epoxide chiral center, giving a secondary alcohol which can be advantageously exploited to raise the ee provided by the synthetic sequence. We also synthesized (+)‐α‐ambrinol by a closely related procedure, showing the synthetic versatility of combining titanium‐catalyzed cyclization with Jacobsen’s epoxidation reactions.
Occupational neck and shoulder pain among automobile manufacturing workers in Iran
Authors: Alipour Akbar , Ghaffari Mostafa , Shariati Batoul , Jensen Irene , Vingard Eva 
Published: February 2008

AbstractBackgroundWork‐related musculoskeletal disorders (MSDs) of the upper extremities are a major problem globally, though most relevant studies have been reported from high income countries.Aims and MethodsThe prevalence of neck and shoulder pain and its association with work‐related physical and psychosocial factors and life style was determined by a cross‐sectional survey using the Nordic Musculoskeletal Questionnaire (NMQ) in the largest Iranian car manufacturing company, with more than 18,000 employees.ResultsA total of 14,384 (79.8%) of all employees completed the questionnaire. Depending on the questions used to measure neck and shoulder symptoms, the prevalence varied widely (from 20.5% to 3.9%). In the multiple logistic regression model, limited to employees with at least 1 year of work experience, risk indicators for disabling pain of the neck and/or shoulder that remained for male were: duration of employment, high visual demands, repetitive work, sitting position at work, awkward working position, no regular exercise, monotonous work, lack of encouraging organizational culture, and anxiety concerning change. For female repetitive work, sitting position at work and no support if there is trouble at work were the only remaining factors.ConclusionsThe study confirms the effects of physical and psychosocial factors on neck and shoulder symptoms among automobile manufacturing workers in a low to middle income country in spite of the relative youth and job insecurity of the population. Am. J. Ind. Med. 51:372–379, 2008. © 2008 Wiley‐Liss, Inc.
Clinical variability of autosomal dominant cataract, microcornea and corneal opacity and novel mutation in the alpha A crystallin gene (CRYAA)
Authors: Richter Leslie , Flodman Pamela , Barria von‐Bischhoffshausen Fernando , Burch Douglas , Brown Sandra , Nguyen Linda , Turner Julia , Spence M. Anne , Bateman J. Bronwyn 
Published: February 2008

AbstractWe studied 28 individuals from a four‐generation Chilean family (ADC54) including 13 affected individuals with cataracts, microcornea and/or corneal opacity. All individuals underwent a complete ophthalmologic exam. We screened with a panel of polymorphic DNA markers for known loci that cause autosomal dominant cataracts, if mutated, and refined the locus using the ABI Prism Linkage Mapping Set Version 2.5, and calculated two‐point lod scores. Novel PCR primers were designed for the three coding exons, including intron–exon borders, of the candidate gene alpha A crystallin (CRYAA). Clinically, affected individuals had diverse and novel cataracts with variable morphology (anterior polar, cortical, embryonal, fan‐shaped, anterior subcapsular). Microcornea and corneal opacity was evident in some. Marker D21S171 gave a lod score of 4.89 (θm = θf = 0). CRYAA had a G414A transition that segregated with the disease and resulted in an amino acid alteration (R116H). The phenotypic variability within this family was significant with novel features of the cataracts and a corneal opacity. With the exception of iris coloboma, the clinical features in all six previously reported families with mutations in the CRYAA gene were found in this family. We identified a novel G414A transition in exon 3 of CRYAA that co‐segregated with an autosomal dominant phenotype. The resulting amino acid change R116H is in a highly conserved region and represents a change in charge. The genotype–phenotype correlation of this previously unreported mutation provides evidence that other factors, genetic and/or environmental, may influence the development of cataract as a result of this alteration. © 2008 Wiley‐Liss, Inc.
Molecular characterization of a de novo ring chromosome 6 in a growth retarded but otherwise healthy woman
Authors: Höckner Martina , Utermann Barbara , Erdel Martin , Fauth Christine , Utermann Gerd , Kotzot Dieter 
Published: February 2008

AbstractThe phenotype of patients with a ring chromosome 6 can be highly variable ranging from almost normal to severe malformations and mental retardation. Size and structure of the ring chromosome as well as the level of mosaicism are important factors for the clinical phenotype. Here, we report on a 25‐year‐old woman with short stature, minor scoliosis, normal fertility, appropriate psychomotor development, minor dysmorphisms, and a de novo ring chromosome 6. Conventional karyotyping as well as molecular cytogenetic and molecular investigations of DUSP22 on 6p and RP1‐191N21.4 on 6q by a new technical approach indicated breakpoints less than 240 kb and less than 190 kb proximal to the telomeres of 6p and 6q, respectively. In addition, formation of the ring chromosome from the paternal chromosome was demonstrated. Thus this case clearly shows that in patients with ring chromosomes without loss of euchromatic material mitotic instability of the ring chromosome is the most important reason for growth retardation and minor congenital anomalies. © 2008 Wiley‐Liss, Inc.
Investigation of ionically crosslinked chitosan and chitosan–bovine serum albumin beads for novel gastrointestinal functionality
Authors: Rayment Phillippa , Butler Michael F. 
Published: February 2008

AbstractThe objective of the work was to determine whether chitosan–tripolyphosphate (TPP) systems can be used to develop safe gel particles for in vivo applications. In particular, we are interested in the use of chitosan systems capable of swelling at low pH in vitro as potentially swellable, satiety‐enhancing ingredients. The formation of homogeneous chitosan‐TPP gel beads was improved by reducing the pH of the TPP gelling bath from 8.5 to 4.0 thus increasing the cationic nature of chitosan and the crosslink density. However, the mechanical strength of this system was reduced compared to the basic system. This has been related to tightening of the gel network by increased shrinking of this system. Although release studies have shown that decreasing the pore size of the gel, by increasing the crosslink density through increasing the TPP concentration, is a good way to trap our model release polymer (dextran), in simulated gastrointestinal conditions, these ionic gel beads showed marked shrinking. We propose that this is due to screening of the charge on the chitosan molecule in the presence of salt and/or an excess of TPP which encourages ionic interactions. We conclude that these ionic gels are an unfeasible alternative satiety‐enhancing ingredient to covalently crosslinked systems. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Electrostatic Stabilization and General Base Catalysis in the Active Site of the Human Protein Disulfide Isomerase a Domain Monitored by Hydrogen Exchange
Authors: Hernández Griselda , Anderson Janet S. , LeMaster David M. 
Published: February 2008

AbstractThe nucleophilic Cys36 thiol of the human protein disulfide isomerase a domain is positioned over the N terminus of the α2 helix. Amides in the active site exhibit diffusion‐limited, hydroxide‐catalyzed exchange, indicating that the local positive electrostatic potential decreases the pK value for peptide anion formation by at least 2 units so as to equal or exceed the acidity of water. In stark contrast to the pH dependence of exchange for simple peptides, the His38 amide in the reduced enzyme exhibits a maximum rate of exchange at pH 5 due to efficient general base catalysis by the neutral imidazole of its own side chain and suppression of its exchange by the ionization of the Cys36 thiol. Ionization of this thiol and deprotonation of the His38 side chain suppress the Cys39 amide hydroxide‐catalyzed exchange by a million‐fold. The electrostatic potential within the active site monitored by these exchange experiments provides a means of stabilizing the two distinct transition states that lead to substrate reduction and oxidation. Molecular modeling offers a role for the conserved Arg103 in coordinating the oxidative transition‐state complex, thus providing further support for mechanisms of disulfide isomerization that utilize enzymatic catalysis at each step of the overall reaction.
Glycine‐immunoreactive neurons in the developing spinal cord of the sea lamprey: Comparison with the γ‐aminobutyric acidergic system
Authors: Villar‐Cerviño Verona , Holstein Gay R. , Martinelli Giorgio P. , Anadón Ramón , Rodicio María Celina 
Published: February 2008

AbstractThe development and cellular distribution of the inhibitory neurotransmitter glycine in the spinal cord of the sea lamprey were studied by immunocytochemistry and double immunofluorescence and compared with the distribution of γ‐aminobutyric acid (GABA). Results in lamprey embryos and prolarvae reveal that the appearance of glycine‐immunoreactive (‐ir) spinal neurons precedes that of GABA‐ir neurons. Throughout development, glycine‐ir cells in the lateral and dorsomedial gray matter of the spinal cord are more numerous than the GABA‐ir cells. Only a subset of these neurons shows colocalization of GABA and glycine, suggesting that they are primarily disparate neuronal populations. In contrast, most cerebrospinal fluid (CSF)‐contacting neurons of the central canal walls are strongly GABA‐ir, and only a portion of them are faintly glycine‐ir. Some edge cells (lamprey intraspinal mechanoreceptors) were glycine‐ir in larvae and adults. The glycine‐ir and GABA‐ir neuronal populations observed in the adult spinal cord were similar to those found in larvae. Comparison of glycine‐ir and GABA‐ir fibers coursing longitudinally in the spinal cord of adult lamprey revealed large differences in diameter between these two types of fiber. Commissural glycine‐ir fibers appear in prolarvae and become numerous at larval stages, whereas crossed GABA‐ir are scarce. Taken together, results in this primitive vertebrate indicate that the spinal glycinergic cells do not arise by biochemical shift of preexisting GABAergic cells but instead suggest that glycine is present in the earliest circuitry of the developing lamprey spinal cord, where it might act transiently as an excitatory transmitter. J. Comp. Neurol. 508:112–130, 2008. © 2008 Wiley‐Liss, Inc.
Monitoring Plasmodium falciparum growth and development by UV flow cytometry using an optimized Hoechst‐thiazole orange staining strategy
Authors: Grimberg Brian T. , Erickson John J. , Sramkoski R. Michael , Jacobberger James W. , Zimmerman Peter A. 
Published: February 2008

AbstractThe complex life cycle of Plasmodium falciparum (Pf) makes it difficult to limit infections and reduce the risk of severe malaria. Improved understanding of Pf blood‐stage growth and development would provide new opportunities to evaluate and interfere with successful completion of the parasite's life cycle. Cultured blood stage Pf was incubated with Hoechst 33342 (HO) and thiazole orange (TO) to stain DNA and total nucleic acids, respectively. Correlated HO and TO fluorescence emissions were then measured by flow cytometry. Complex bivariate data patterns were analyzed by manual cluster gating to quantify parasite life cycle stages. The permutations of viable staining with both reagents were tested for optimal detection of parasitized RBC (pRBC). Pf cultures were exposed to HO and TO simultaneously to achieve optimal staining of pRBC and consistent quantification of early and late stages of the replicative cycle (rings through schizonts). Staining of Pf nucleic acids allows for analysis of parasite development in the absence of fixatives, lysis, or radioactivity to enable examination of erythrocytes from parasite invasion through schizont rupture using sensitive and rapid assay procedures. Investigation of the mechanisms by which anti‐malarial drugs and antibodies act against different Pf lifecycle stages will be aided by this cytometric strategy. © 2008 International Society for Advancement of Cytometry
Resistance of mtDNA‐depleted cells to apoptosis
Authors: Ferraresi Roberta , Troiano Leonarda , Pinti Marcello , Roat Erika , Lugli Enrico , Quaglino Daniela , Taverna Daniela , Bellizzi Dina , Passarino Giuseppe , Cossarizza Andrea 
Published: February 2008

AbstractCells lacking mitochondrial genome (defined as ρ0) are useful models in studies on cancer, aging, mitochondrial diseases and apoptosis, but several of their functional aspects have been poorly characterized. Using different clones of ρ0 cells derived from the human osteosarcoma line 143B, we have tested the effects of different apoptogenic molecules such as staurosporine (STS), doxorubicin, daunomycin and quercetin, and have analyzed apoptosis, mitochondrial membrane potential (MMP), levels of oxygen free radicals, reduced glutathione (GSH) content, and expression of P‐glycoprotein (P‐gp). When compared to parental cells, ρ0 cells resulted much less sensitive to apoptosis. MMP was well maintained in ρ0 cells, and remained unchanged after adding apoptogenic agents, and did not change after treatment with molecules able to depolarize mitochondria such as valinomycin. After adding STS, the production of reactive oxygen species was similar in both cell types, but ρ0 cells maintained higher levels of GSH. In ρ0 cells, P‐gp was strongly over‐expressed both at mRNA and protein level, and its functionality was higher. The resistance to apoptosis of ρ0 cells could be not only due to an increased scavenger capacity of GSH, but also due to a selection of multidrug resistant cells that hyperexpress P‐gp. © 2008 International Society for Advancement of Cytometry
Dendritic cell subsets in the peritoneal fluid and peripheral blood of women suffering from ovarian cancer
Authors: Wertel I. , Polak G. , Bednarek W. , Barczyński B. , Roliński J. , Kotarski J. 
Published: February 2008

AbstractBackground:Evaluation of immature myeloid and lymphoid dendritic cells (DCs) in the peritoneal fluid (PF) and peripheral blood (PB) mononuclears of women with ovarian carcinoma (n = 47) and benign ovarian tumors (n = 37).Methods:Mononuclear cells were isolated from PF and PB, stained with monoclonal antibodies (mAbs) against DC antigens (anti‐BDCA‐1, anti‐BDCA‐2), and estimated using flow cytometry.Results:The percentage of PF myeloid DC (MDC) in mononuclears was significantly lower in patients with ovarian cancer in comparison to the group of nonmalignant ovarian tumors (0.65% and 6.95%). The percentage of PF lymphoid DCs (LDCs) was higher in patients with ovarian cancer than in the reference group (0.64% and 0.09%). The percentage of PB MDCs and LDCs did not differ significantly between studied groups. In women suffering from ovarian cancer the percentage of both MDCs and LDCs was higher in the PF than in the PB. In the reference group the percentage of MDCs was higher but that of LDCs was lower in the PF than in the PB. In women with ovarian cancer, PF MDCs/LDCs ratio was lower in comparison to patients with serous cystadenoma. In PB the ratio of MDCs to LDCs did not differ significantly between studied groups.Conclusions:We concluded that MDCs population may be affected by the presence of malignant disease. LDC subsets may have influence on the local immune response in the PF of women with malignant tumors of the ovary. © 2008 Clinical Cytometry Society
They heard a cry: psychosocial resources moderate perception of others' distress
Authors: Harber Kent D. , Einev‐Cohen Michal , Lang Fran 
Published: February 2008

AbstractTwo studies tested whether psychosocial resources affect perception of another's distress. Participants' had their resources depleted, left unchanged, or boosted by elaborately recalling either someone who had betrayed them, a neutral person, or a close and trusted other, respectively. Participants then listened to disturbing baby cries, and rated how much distress the cries conveyed. As predicted, participants who recalled a betrayal subsequently heard the cries as conveying more distress than did other participants (Study 1). However, recalling a betrayal did not amplify cry ratings if, prior to cry rating, betrayal‐related thoughts and feelings were disclosed (Study 2). The moderating effect of disclosure on cry ratings indicates that boosting resources (disclosure) can counteract the effects of resource depletion (betrayal). Results in both studies remained significant even after controlling for mood. This research is the first to show that social contexts, and emotional disclosure, each affects perception of others' distress. Copyright © 2007 John Wiley & Sons, Ltd.