bluuebunny/crossref_metadata_2025_split huggingface dataset:
Invasion of dwarf bamboo into alpine snow‐meadows in northern Japan: pattern of expansion and impact on species diversity
Authors: Kudo Gaku , Amagai Yukihiro , Hoshino Buho , Kaneko Masami 
Published: August 2011

AbstractRecently, a dwarf bamboo species, Sasa kurilensis; Poaceae, has invaded into alpine snow‐meadows in the wilderness area of the Taisetsu Mountains, northern Japan. This dwarf bamboo species has a wide distribution range from lowland to alpine sites of snowy regions. Because of the formation of dense evergreen culms and an extensive rhizome system, other plants are excluded following invasion by this dwarf bamboo, resulting in low species diversity. Dwarf bamboo originally inhabited the leeward slopes of alpine dwarf pine (Pinus pumila) clumps in alpine regions. During the last 32 years, however, dwarf bamboo has expanded its distribution area by up to 47% toward snow‐meadows, especially on southeastern facing slopes. This rapid change may be related to the decrease in soil moisture and expansion of the annual growing period caused by the recent acceleration of snowmelt time. A multiyear census revealed that the density of bamboo culms increased 30–150% during 2 years, and the annual expansion of bamboo rhizomes was 39 cm on average. In addition to the expansion of bamboo clumps by vegetative growth, the possibility of migration by seed dispersal was also suggested by a genet analysis. With the increase in culm density, the species richness of snow‐meadow vegetation decreased to less than one‐quarter of the original level due to intense shading by dwarf bamboo. The rapid vegetation change in these almost pristine alpine environments isolated from the human activity implies that global climate change already influences the alpine ecosystem.
The Diastereoselective Formation of Tetraalkoxy[4]resorcinarenes Derived from (–)‐(2R)‐2‐Methoxy‐2‐phenylethanol and Proof of Absolute Configurations
Authors: Bulman Page Philip C. , Chan Yohan , Heaney Harry , McGrath Matthew J. , Moreno Eduardo 
Published: August 2011

AbstractThe preparation of optically pure (–)‐3‐[(2R)‐2‐methoxy‐2‐phenylethoxy]phenol from resorcinol monobenzoate and its conversion into diastereoisomeric tetraalkoxyresorcin[4]arenes together with proof of the absolute configurations of the products is reported. The results of the study indicate that diastereoselective ring closure of linear tetrameric intermediates is controlled by the steric demand of the alkyl group in the precursor 3‐alkoxyphenol.
Ruthenium‐Catalyzed Oxidative Dearomatization of Phenols to 4‐(tert‐Butylperoxy)cyclohexadienones: Synthesis of 2‐Substituted Quinones from p‐Substituted Phenols
Authors: Murahashi Shun‐Ichi , Miyaguchi Noriko , Noda Shinji , Naota Takeshi , Fujii Akiko , Inubushi Yasutaka , Komiya Naruyoshi 
Published: August 2011

AbstractThe ruthenium‐catalyzed oxidation of phenols with tert‐butylhydroperoxide efficiently gives the corresponding 4‐(tert‐butylperoxy)cyclohexadienones. The oxidation proceeds selectively because of ruthenium's ability for rapid single‐electron transfer. This biomimetic oxidation reaction is highly useful to obtain the metabolic compounds desired for confirming the safety of medicines and related compounds. Typically, the first metabolic compound of the female hormone estrone is readily obtained by this biomimetic oxidation reaction. The resulting 4‐(tert‐butylperoxy)cyclohexadienones are versatile synthetic intermediates, which can be transformed into 2‐substituted 1,4‐benzoquinones by treatment with acid catalysts. Acid‐promoted rearrangement followed by a Diels–Alder reaction provides a new strategy for the synthesis of fused cyclic compounds, such as naphthoquinone and anthraquinone derivatives, from readily available phenols. The nonnatural 1,4‐diacetoxy steroidal skeleton is obtained by the oxidation of estrone followed by zinc‐mediated migration. Vitamin K3 is synthesized selectively from p‐cresol in an overall 79 % yield in 4 steps, and the synthesis includes the ruthenium‐catalyzed oxidation.
Double‐layer polarization of a non‐conducting particle in an alternating current field with applications to dielectrophoresis
Authors: Zhao Hui 
Published: August 2011

AbstractDielectrophoresis is becoming one of the most important techniques in particle manipulation including particle separation, particle assembly, and biomolecule characterization. Understanding dielectrophoretic properties of particles is a key step toward effective and efficient particle manipulation. Theoretical studies of polarization of a particle can help to understand experimental observations and also go beyond to develop a predictive theory to guide the experimental design. This article discusses recent theoretical advances in the polarization of a dielectric particle, in particular, the polarization of the electric double layer. The double‐layer polarization is critical to determine particle dynamics in dielectrophoresis. The dipole moment characterizing the strength of this polarization depends on the double‐layer thickness, the electric field frequency, the particle's surface charge, and other surface's properties (Pohl, H. A., Dielectrophoresis, Cambridge University Press, New York 1978). After a brief review of the mathematical model, the focus is on the following problems: (i) the polarization of a spherical particle; (ii) the polarization of an elongated cylindrical particle; (iii) the effect of the slip on the polarization of a particle. The double‐layer polarization is examined here in the context of high‐frequency and low‐frequency dispersions induced by surface conduction and diffusion, respectively.
Cascade and staggered dielectrophoretic cell sorters
Authors: Yang Fang , Yang Xiaoming , Jiang Hong , Wang Guiren 
Published: August 2011

AbstractWe have developed two new microfluidic cell sorters based on conventional negative dielectrophoresis (DEP) for continuous flow operations. The first is a cascade configuration sorter designed to increase purity of isolated target cell. The second has two staggered side channels in opposite side walls to increase sample throughput without compromising enrichment factor. Particles (carboxylate microspheres) of different sizes were first used to demonstrate the feasibility of the present DEP sorters for cell isolation. Then biological cells, i.e. human prostate cancer cell line LNCaP and human colorectal cancer cell line HCT116 were used to test the performance of the DEP sorters. In the present work, applied voltage was in the range of 0–20 Vp‐p, and frequency was from 0 to 10 MHz. Comparing to a single side channel DEP cell sorter, the isolation purity was improved from 80 to 96% by a single cascade sorter and the sample throughput was increased from 0.2 to 0.65 μL/min by a single staggered side channel sorter. In this article, we report the cell sorter designs, cell separation and enrichment factors.
Monitoring humans for somatic mutation in the endogenous pig‐a gene using red blood cells
Authors: Dobrovolsky Vasily N. , Elespuru Rosalie K. , Bigger C. Anita H. , Robison Timothy W. , Heflich Robert H. 
Published: August 2011

AbstractThe endogenous X‐linked PIG‐A gene is involved in the synthesis of glycosyl phosphatidyl inositol (GPI) anchors that tether specific protein markers to the exterior of mammalian cell cytoplasmic membranes. Earlier studies in rodent models indicate that Pig‐a mutant red blood cells (RBCs) can be induced in animals treated with genotoxic agents, and that flow cytometry can be used to identify rare RBCs deficient in the GPI‐anchored protein, CD59, as a marker of Pig‐a gene mutation. We investigated if a similar approach could be used for detecting gene mutation in humans. We first determined the frequency of spontaneous CD59‐deficient RBCs (presumed PIG‐A mutants) in 97 self‐identified healthy volunteers. For most subjects, the frequency of CD59‐deficient RBCs was low (average of 5.1 ± 4.9 × 10−6; median of 3.8 × 10−6 and mutant frequency less than 8 × 10−6 for 75% of subjects), with a statistically significant difference in median mutant frequencies between males and females. PIG‐A RBC mutant frequency displayed poor correlation with the age and no correlation with the smoking status of the subjects. Also, two individuals had markedly increased CD59‐deficient RBC frequencies of ∼300 × 10−6 and ∼100 × 10−6. We then monitored PIG‐A mutation in 10 newly diagnosed cancer patients undergoing chemotherapy with known genotoxic drugs. The frequency of CD59‐deficient RBCs in the blood of the patients was measured before the start of chemotherapy and three times over a period of ∼6 months while on/after chemotherapy. Responses were generally weak, most observations being less than the median mutant frequency for both males and females; the greatest response was an approximate three‐fold increase in the frequency of CD59‐deficient RBCs in one patient treated with a combination of cisplatin and etoposide. These results suggest that the RBC PIG‐A assay can be adopted to measuring somatic cell mutation in humans. Further research is necessary to determine the assay's sensitivity in detecting mutations induced by genotoxic agents acting via different mechanisms. Environ. Mol. Mutagen., 2011. Published 2011 Wiley‐Liss, Inc.
Practical applications of multi‐agent systems in electric power systems
Authors: Catterson Victoria M. , Davidson Euan M. , McArthur Stephen D. J. 
Published: August 2011

SUMMARYThe transformation of energy networks from passive to active systems requires the embedding of intelligence within the network. One suitable approach to integrating distributed intelligent systems is multi‐agent systems technology, where components of functionality run as autonomous agents capable of interaction through messaging. This provides loose coupling between components that can benefit the complex systems envisioned for the smart grid. This paper reviews the key milestones of demonstrated agent systems in the power industry and considers which aspects of agent design must still be addressed for widespread application of agent technology to occur. Copyright © 2011 John Wiley & Sons, Ltd.
Restless legs syndrome in older people: a community‐based study on its prevalence and association with major depressive disorder in older Korean adults
Authors: Kim Won‐Hyoung , Kim Byung‐Soo , Kim Shyn‐Kyum , Chang Sung‐Man , Lee Dong‐Woo , Cho Maeng‐Je , Bae Jae Nam 
Published: August 2011

ObjectiveThe prevalence of restless legs syndrome (RLS) and its relationship with the demographic variables in an older Korean population were examined.MethodsA face‐to‐face household survey was conducted in five different regions of Korea from June 2008 to August 2008. Among a total of 3074 individuals who were aged more than 65, 1990 participants were interviewed, and the response rate was 64.7%. The diagnosis of RLS was made using an RLS questionnaire. The medical review of systems was assessed by a self‐report questionnaire containing 15 items. Depression was diagnosed with the diagnostic section of depressive disorder of the Korean version of the Composite International Diagnostic Interview (CIDI) and the short form of the Geriatric Depression Scale (GDS).ResultsThe prevalence of RLS in the older Korean population was 9.5% (men, 7.1%; women, 11.3%). RLS had a significant association with anemia (odds ratio (OR), 1.66; 95% confidence interval (CI), 1.29–2.12; P < 0.001) and renal diseases (OR, 2.57; 95% CI, 1.95–3.38; P < 0.001). RLS seemed to have a significant relationship with depression by using the CIDI (adjusted OR 2.01; 95% CI, 1.45–2.79. P < 0.001) and GDS (adjusted OR, 1.62; 95% CI, 1.34–1.94; P < 0.001).ConclusionsRestless legs syndrome might be a risk factor for major depressive disorder in older Koreans. Future investigations should focus on the causality and mechanism underlying the relationship between RLS and major depressive disorder. Copyright © 2011 John Wiley & Sons, Ltd.
A group music intervention using percussion instruments with familiar music to reduce anxiety and agitation of institutionalized older adults with dementia
Authors: Sung Huei‐chuan , Lee Wen‐li , Li Tzai‐li , Watson Roger 
Published: August 2011

ObjectiveThis experimental study aimed to evaluate the effects of a group music intervention on anxiety and agitation of institutionalized older adults with dementia.MethodsA total of 60 participants were randomly assigned to an experimental or a control group. The experimental group received a 30‐min music intervention using percussion instruments with familiar music in a group setting in mid afternoon twice weekly for 6 weeks, whereas the control group received usual care with no music intervention. The Rating of Anxiety in Dementia scale was used to assess anxiety, and Cohen‐Mansfield Agitation Inventory was used to assess agitation at baseline, week 4 and week 6.ResultsRepeated measures analysis of covariance indicated that older adults who received a group music intervention had a significantly lower anxiety score than those in the control group while controlling for pre‐test score and cognitive level (F = 8.98, p = 0.004). However, the reduction of agitation between two groups was not significantly different.ConclusionsAnxiety and agitation are common in older adults with dementia and have been reported by caregivers as challenging care problems. An innovative group music intervention using percussion instruments with familiar music as a cost‐effective approach has the potential to reduce anxiety and improve psychological well‐being of those with dementia. Copyright © 2011 John Wiley & Sons, Ltd.
Functional MRI assessment of orofacial articulators: Neural correlates of lip, jaw, larynx, and tongue movements
Authors: Grabski Krystyna , Lamalle Laurent , Vilain Coriandre , Schwartz Jean‐Luc , Vallée Nathalie , Tropres Irène , Baciu Monica , Le Bas Jean‐François , Sato Marc 
Published: August 2011

AbstractCompared with complex coordinated orofacial actions, few neuroimaging studies have attempted to determine the shared and distinct neural substrates of supralaryngeal and laryngeal articulatory movements when performed independently. To determine cortical and subcortical regions associated with supralaryngeal motor control, participants produced lip, tongue and jaw movements while undergoing functional magnetic resonance imaging (fMRI). For laryngeal motor activity, participants produced the steady‐state/i/vowel. A sparse temporal sampling acquisition method was used to minimize movement‐related artifacts. Three main findings were observed. First, the four tasks activated a set of largely overlapping, common brain areas: the sensorimotor and premotor cortices, the right inferior frontal gyrus, the supplementary motor area, the left parietal operculum and the adjacent inferior parietal lobule, the basal ganglia and the cerebellum. Second, differences between tasks were restricted to the bilateral auditory cortices and to the left ventrolateral sensorimotor cortex, with greater signal intensity for vowel vocalization. Finally, a dorso‐ventral somatotopic organization of lip, jaw, vocalic/laryngeal, and tongue movements was observed within the primary motor and somatosensory cortices using individual region‐of‐interest (ROI) analyses. These results provide evidence for a core neural network involved in laryngeal and supralaryngeal motor control and further refine the sensorimotor somatotopic organization of orofacial articulators. Hum Brain Mapp 33:2306–2321, 2012. © 2011 Wiley Periodicals, Inc.
Effects of rapid eye movement sleep deprivation on fear extinction recall and prediction error signaling
Authors: Spoormaker Victor I. , Schröter Manuel S. , Andrade Kátia C. , Dresler Martin , Kiem Sara A. , Goya‐Maldonado Roberto , Wetter Thomas C. , Holsboer Florian , Sämann Philipp G. , Czisch Michael 
Published: August 2011

AbstractIn a temporal difference learning approach of classical conditioning, a theoretical error signal shifts from outcome deliverance to the onset of the conditioned stimulus. Omission of an expected outcome results in a negative prediction error signal, which is the initial step towards successful extinction and may therefore be relevant for fear extinction recall. As studies in rodents have observed a bidirectional relationship between fear extinction and rapid eye movement (REM) sleep, we aimed to test the hypothesis that REM sleep deprivation impairs recall of fear extinction through prediction error signaling in humans. In a three‐day design with polysomnographically controlled REM sleep deprivation, 18 young, healthy subjects performed a fear conditioning, extinction and recall of extinction task with visual stimuli, and mild electrical shocks during combined functional magnetic resonance imaging (fMRI) and skin conductance response (SCR) measurements. Compared to the control group, the REM sleep deprivation group had increased SCR scores to a previously extinguished stimulus at early recall of extinction trials, which was associated with an altered fMRI time‐course in the left middle temporal gyrus. Post‐hoc contrasts corrected for measures of NREM sleep variability also revealed between‐group differences primarily in the temporal lobe. Our results demonstrate altered prediction error signaling during recall of fear extinction after REM sleep deprivation, which may further our understanding of anxiety disorders in which disturbed sleep and impaired fear extinction learning coincide. Moreover, our findings are indicative of REM sleep related plasticity in regions that also show an increase in activity during REM sleep. Hum Brain Mapp 33:2362–2376, 2012. © 2011 Wiley Periodicals, Inc.
Dissociable neural correlates of contour completion and contour representation in illusory contour perception
Authors: Wu Xiang , He Sheng , Bushara Khalaf , Zeng Feiyan , Liu Ying , Zhang Daren 
Published: August 2011

AbstractObject recognition occurs even when environmental information is incomplete. Illusory contours (ICs), in which a contour is perceived though the contour edges are incomplete, have been extensively studied as an example of such a visual completion phenomenon. Despite the neural activity in response to ICs in visual cortical areas from low (V1 and V2) to high (LOC: the lateral occipital cortex) levels, the details of the neural processing underlying IC perception are largely not clarified. For example, how do the visual areas function in IC perception and how do they interact to archive the coherent contour perception? IC perception involves the process of completing the local discrete contour edges (contour completion) and the process of representing the global completed contour information (contour representation). Here, functional magnetic resonance imaging was used to dissociate contour completion and contour representation by varying each in opposite directions. The results show that the neural activity was stronger to stimuli with more contour completion than to stimuli with more contour representation in V1 and V2, which was the reverse of that in the LOC. When inspecting the neural activity change across the visual pathway, the activation remained high for the stimuli with more contour completion and increased for the stimuli with more contour representation. These results suggest distinct neural correlates of contour completion and contour representation, and the possible collaboration between the two processes during IC perception, indicating a neural connection between the discrete retinal input and the coherent visual percept. Hum Brain Mapp 33:2407–2414, 2012. © 2011 Wiley Periodicals, Inc.
Seasonal variation in the patient diagnosis of primary biliary cirrhosis: Further evidence for an environmental component to etiology
Authors: McNally Richard J.Q. , James Peter W. , Ducker Samantha , James Oliver F.W. 
Published: August 2011

Abstract

The etiology of primary biliary cirrhosis (PBC) is far from clear. Both genetic and environmental factors are likely to be involved. We have previously reported evidence of space-time clustering, suggesting that a transient environmental agent may be involved in etiology. To further examine whether a seasonally varying environmental agent may contribute to the etiology of PBC, we have analyzed seasonal variation with respect to month of diagnosis using population-based data from northeast England over a defined period (1987-2003). Date of diagnosis was defined as the earliest date at which the patient was found to have fulfilled any two of three diagnostic criteria (i.e., antimitochondrial antibody–positive titer ≥1 in 40, cholestatic liver blood tests, diagnostic or compatible liver histology). Monthly expected (E) numbers of cases were calculated under an assumption of a uniform distribution throughout the year. Observed counts (O) were compared with the expected numbers. The chi-squared heterogeneity test was used to test for overall nonuniform variation and also for individual months. Poisson regression analysis was used to fit a sinusoidal (i.e., harmonic) model to the data, using month of diagnosis as a covariate in the model. There was a marked peak for diagnoses in the month of June (O = 115, E = 84.7, O/E = 1.36;

P

= 0.001). Furthermore, there was evidence of a sinusoidal pattern with a June peak (

P

= 0.012).

Conclusion:

These highly novel results provide further evidence for the involvement of a seasonally varying environmental agent in the etiology of PBC. (Hepatology 2011)
An essential role for monocyte chemoattractant protein-1 in alcoholic liver injury: Regulation of proinflammatory cytokines and hepatic steatosis in mice
Authors: Mandrekar Pranoti , Ambade Aditya , Lim Arlene , Szabo Gyongyi , Catalano Donna 
Published: August 2011

Abstract

The importance of chemokines in alcoholic liver injury has been implicated. The role of the chemokine, monocyte chemoattractant protein-1 (MCP-1), elevated in patients with alcoholic liver disease is not yet understood. Here, we evaluated the pathophysiological significance of MCP-1 and its receptor, chemokine (C-C motif) receptor 2 (CCR2), in alcoholic liver injury. The Leiber-DeCarli diet containing alcohol or isocaloric control diets were fed to wild-type (WT) and MCP-1-deficient knockout (KO) mice for 6 weeks.

In vivo

and

in vitro

assays were performed to study the role of MCP-1 in alcoholic liver injury. MCP-1 was increased in Kupffer cells (KCs) as well as hepatocytes of alcohol-fed mice. Alcohol feeding increased serum alanine aminotransferase in WT and CCR2KO, but not MCP-1KO, mice. Alcohol-induced liver steatosis and triglyceride were attenuated in alcohol-fed MCP-1KO, but high in CCR2KO mice, compared to WT, whereas serum endotoxin was high in alcohol-fed WT and MCP-1KO mice. Expression of liver proinflammatory cytokines tumor necrosis factor alpha, interleukin (IL)-1β, IL-6, KC/IL-8, intercellular adhesion molecule 1, and cluster of differentiation 68 was induced in alcohol-fed WT, but inhibited in MCP-1KO, mice independent of nuclear factor kappa light-chain enhancer of activated B cell activation in KCs. Oxidative stress, but not cytochrome P450 2E1, was prevented in chronic alcohol-fed MCP-1KO mice, compared to WT. Increased expression of peroxisome proliferator-activated receptor (PPAR)α and PPARγ was accompanied by nuclear translocation, DNA binding, and induction of fatty acid metabolism genes acyl coenzyme A oxidase and carnitine palmitoyltransferase 1A in livers of alcohol-fed MCP-1KO mice, compared to WT controls.

In vitro

assays uncovered an inhibitory effect of recombinant MCP-1 on PPARα messenger RNA and peroxisome proliferator response element binding in hepatocytes independent of CCR2.

Conclusion:

Deficiency of MCP-1 protects mice against alcoholic liver injury, independent of CCR2, by inhibition of proinflammatory cytokines and induction of genes related to fatty acid oxidation, linking chemokines to hepatic lipid metabolism. (Hepatology 2011)