bluuebunny/crossref_metadata_2025_split huggingface dataset:
Exact solutions for Sturm–Liouville problems on trees via novel substitute systems and the Wittrick–Williams algorithm
Authors: Williams Fred W , Watson Andrew , Paul Howson W , Jones Antonia J 
Published: September 2007

Since 1970, the Wittrick–Williams algorithm has been applied with increasing sophistication in structural mechanics to guarantee that eigenvalues cannot be missed and are calculated accurately. The underlying theorem enables its application to any discipline requiring eigenvalues of self-adjoint systems of differential equations. Its value in mathematics was recently illustrated by studying Sturm–Liouville equations on large homogeneous trees with Dirichlet boundary conditions and
n
(≤43) levels.
Recursive subsysteming
was applied
n
−1 times to assemble the tree progressively from sub-trees. Hence, numerical results confirmed the recent theoretical bounds of Sobolev & Solomyak for
n
→∞. In addition, a structural mechanics analogy yielded a proof that many eigenvalues had high multiplicities determined by
n
and the branching number
b
.

Inspired by the structural mechanics analogy, we now prove that all eigenvalues of the tree are obtainable from
n
substitute chains
r
(=1, 2, …,
n
) which involve only
r
consecutively linked differential equations and which have only singlefold eigenvalues. Equations are also derived for the multiplicities these eigenvalues have for the tree. Hence, double precision calculations on a PC readily gave eigenvalues for
n
=10
6
and
b
=10, i.e. ≃10
999 999
linked Sturm–Liouville equations. Moreover, a simple equation is derived which gives all the eigenvalues of uniform trees with Dirichlet conditions at both ends, and band-gap spectra are numerically demonstrated and theoretically justified for trees with the Dirichlet conditions at either end replaced by Neumann ones. Additionally, even if each multiple eigenvalue would be counted as if it were singlefold, the proportion of eigenvalues that are multiple is proved to approach unity as
n
→∞.
Increased susceptibility of Sf1+/– mice to azoxymethane‐induced colon tumorigenesis
Authors: Shitashige Miki , Satow Reiko , Honda Kazufumi , Ono Masaya , Hirohashi Setsuo , Yamada Tesshi 
Published: September 2007

Aberrant transactivation of a certain set of target genes by the β‐catenin and T‐cell factor‐4 nuclear complex has been considered crucial for the initiation of colorectal carcinogenesis. We previously identified splicing factor‐1 (SF1) as a novel component of the β‐catenin and T‐cell factor‐4 complex, and showed that the overexpression of SF1 inhibited the gene transactivational activity of the complex and markedly suppressed β‐catenin‐evoked colony formation by human embryonic kidney 293 cells. However, the involvement of SF1 in the process of carcinogenesis in vivo remains unclear. In the present study, we established SF1‐knockout mice using the gene trapping method. Homozygous mice (Sf1−/–) died during embryonic development before embryonic day (E)8.5, whereas heterozygous (Sf1+/–) mice were born alive and developed normally. Azoxymethane (AOM) was given at a dose of 10 mg/kg body weight once a week for 6 weeks to 7‐week‐old Sf1+/– and Sf1+/+ mice. At 23 weeks after the start of AOM the average number (5.5 ± 0.6 versus 2.2 ± 0.2 in females [P = 0.003, Mann–Whitney U‐test], 3.7 ± 0.2 versus 1.7 ± 0.7 in males [P = 0.014]) and volume of colon tumors per mouse (8.7 ± 1.6 versus 2.2 ± 0.5 mm3 per female [P = 0.0008], 11.3 ± 3.4 versus 0.6 ± 0.2 mm3 per male [P = 0.001]) were significantly higher in Sf1+/– than in Sf1+/+ mice. The increased susceptibility of Sf1+/– mice to AOM‐induced colon tumorigenesis indicates the crucial involvement of SF1 in the β‐catenin‐mediated regulation of proliferation and differentiation of intestinal epithelial cells. (Cancer Sci 2007; 98: 1862–1867)
Thyrotoxic hypokalaemic periodic paralysis in a Turkish population: three new case reports and analysis of the case series
Authors: Cesur Mustafa , Bayram Fahri , Temel Mehtap Akcil , Ozkaya Mesut , Kocer Abdulkadir , Ertorer Melek Eda , Koc Filiz , Kaya Ahmet , Gullu Sevim 
Published: September 2007

SummaryObjective  Thyrotoxic hypokalaemic periodic paralysis (THPP) is an uncommon condition with intermittent episodes of muscle weakness and occasionally severe paralysis. THPP is a common complication of hyperthyroidism in Asian populations, and has also been reported in other ethnic groups including Caucasians. This study aimed to conduct an analysis of THPP in a Turkish population, and is to our knowledge the first analysis of a homogeneous Caucasian group.Subjects  Forty cases with THPP were identified in the Turkish population. Three out of the 40 were new cases and were assigned as index cases. Two cases were not included in the analysis because of lack of data.Results  THPP was diagnosed in 10 cases during the first attack and was observed to have a significant shorter complete recovery time statistically in this group (P < 0·01). The majority of cases were hypokalaemic, while there were two normokalaemic cases. Classification of the cases according to their potassium (K) levels revealed that the group with K levels < 2·5 mEq/l had a statistically longer amelioration time than the group with K levels ≥ 2·5 mEq/l. When the cases were classified according to intravenous or oral application of K, the mean amelioration time was 6·8 ± 3·6 h for the intravenous group and 13·1 ± 7·6 for the oral group. Mean complete recovery times of the groups were 29·4 ± 16·2 h and 52·8 ± 18·0 h, respectively. The intravenous group had a shorter amelioration time and complete recovery time, and both were statistically significant (P < 0·05 for each).Conclusions  THPP may be seen among Caucasians. Diagnosing THPP during the first attack might decrease the recovery time. The level of hypokalaemia seems to affect the recovery time and initial low K levels may lead to more deterioration in a patient's health compared with mild or near‐normal levels. Intravenous, rather than oral, application of K may be advantageous for shortening both the amelioration and complete recovery times.
Detection and significance of koi herpesvirus (KHV) in freshwater environments
Authors: MATSUI KAZUAKI , HONJO MIE , KOHMATSU YUKIHIRO , UCHII KIMIKO , YONEKURA RYUJI , KAWABATA ZEN'ICHIRO 
Published: September 2007

Summary1. Koi herpesvirus (KHV) disease, a lethal disease in carp and koi, has spread rapidly since the late 1990s. Only a few studies have focused on the ecology of KHV in natural freshwater environments, although characterization and the diagnosis of KHV disease have been intensively studied. This is mainly due to the lack of reliable detection methods for KHV in natural environments.2. Three different approaches have been used to detect KHV in fish samples: (i) isolation and identification of the virus using cultured cell lines; (ii) detection of viral DNA with target DNA amplification techniques; and (iii) detection of anti‐KHV antibodies using an enzyme‐linked immunosorbent assay (ELISA). Among these methods, DNA amplification techniques have become most popular because of their sensitivity and simplicity.3. In contrast to KHV detection in fish samples, detection of KHV from water and sediment samples has not been reported. This is the result of a lack of reliable KHV concentration methods for water and sediment samples, although methodology from public health and marine microbiology may be applicable to determine KHV concentration in such samples.4. Few reports have evaluated the environmental factors (e.g. temperature, UV irradiation) that affect the fate of KHV in water bodies. Mass mortality of wild carp caused by KHV infection would result in the removal of a large omnivorous fish from freshwater ecosystems and may thus alter community structure and ecosystem functioning.
Emergent body size of mayfly survivors
Authors: ALEXANDER ALEXA C. , HEARD KRISTIE S. , CULP JOSEPH M. 
Published: September 2007

Summary1. Employing field‐deployed mesocosms, we examined the effects of 12‐h pulse and 20‐day press (continuous) exposures of the common agricultural insecticide, imidacloprid, on nymph abundance, emergence patterns and adult body size of Epeorus spp. (Heptageniidae) and Baetis spp. (Baetidae).2. In press exposures, reduced nymph density was driven by reduced survivorship; in pulse exposures, reduced nymph density may reflect increased emergence because of stress.3. Once exposed to imidacloprid, Epeorus and Baetis mayflies developed less and emerged smaller than their control counterparts. Concentrations as low as 0.1 μg L−1 (12‐h pulse) reduced head length in Baetis and thorax length in Epeorus.4. In all of the Baetis and Epeorus examined, effects were only found in males. Male survivorship and body size can affect population dynamics. Sublethal doses of this widely applied agricultural insecticide have the potential to reduce reproductive success of mayfly populations.
A real spectral analysis of the deformation of a homogenous electric field over a thin bed – A Hartley transform approach
Authors: Sundararajan N. , Al‐Garni Mansour A. , Ramabrahmam G. , Srinivas Y. 
Published: September 2007

ABSTRACTSpectral analysis of the deformation of a homogenous electric field caused by a long, thin inclined bed, which is of considerable importance in the exploration of ground water and minerals, is presented using the Hartley transform. The Hartley transform is an alternative and real replacement for the well‐known complex Fourier transform in the field of spectral analysis. The thickness of the bed and the inclination are given as functions of frequency by simple expressions. A theoretical example illustrates the method while the applicability is demonstrated by the field examples from the fractured crystalline basement complex in Burkina Faso, Africa and the Precambrian limestones of the Cuddapah basin, Andhra Pradesh, India. The results obtained by this method agree well with those of the drilling.
Importance of borehole deviation surveys for monitoring of hydraulic fracturing treatments
Authors: Bulant Petr , Eisner Leo , Pšenčík Ivan , Calvez Joël Le 
Published: September 2007

ABSTRACTDuring seismic monitoring of hydraulic fracturing treatment, it is very common to ignore the deviations of the monitoring or treatment wells from their assumed positions. For example, a well is assumed to be perfectly vertical, but in fact, it deviates from verticality. This can lead to significant errors in the observed azimuth and other parameters of the monitored fracture‐system geometry derived from microseismic event locations. For common hydraulic fracturing geometries, a 2° deviation uncertainty on the positions of the monitoring or treatment well survey can cause a more than 20° uncertainty of the inverted fracture azimuths. Furthermore, if the positions of both the injection point and the receiver array are not known accurately and the velocity model is adjusted to locate perforations on the assumed positions, several‐millisecond discrepancies between measured and modeled SH‐P traveltime differences may appear along the receiver array. These traveltime discrepancies may then be misinterpreted as an effect of anisotropy, and the use of such anisotropic model may lead to the mislocation of the detected fracture system. The uncertainty of the relative positions between the monitoring and treatment wells can have a cumulative, nonlinear effect on inverted fracture parameters. We show that incorporation of borehole deviation surveys allows reasonably accurate positioning of the microseismic events. In this study, we concentrate on the effects of horizontal uncertainties of receiver and perforation positions. Understanding them is sufficient for treatment of vertical wells, and also necessary for horizontal wells.
Changes in spring arrival of Nearctic‐Neotropical migrants attributed to multiscalar climate
Authors: MACMYNOWSKI DENA P. , ROOT TERRY L. , BALLARD GRANT , GEUPEL GEOFFREY R. 
Published: September 2007

AbstractClimate‐related changes associated with the California marine ecosystem have been documented; however, there are no studies assessing changes in terrestrial vertebrate phenology on the Pacific coast of western North America. We analyze the spring phenology of 21 Nearctic‐Neotropical migratory songbird species in central and northern CA. Using observational and banding data at multiple sites, we evaluate evidence for a change in arrival timing being linked to either nonclimatic or multiscalar climatic explanations. Using correlation analysis, of the 13 species with a significant (P<0.10) change in arrival, the arrival timing of 10 species (77%) is associated with both temperature and a large‐scale climate oscillation index (El Niño Southern Oscillation, ENSO; North Atlantic Oscillation, NAO; and/or Pacific Decadal Oscillation, PDO) at least at one location. Eight of the 13 species (62%) are advancing their migratory timing. All species for which spring arrival is associated with climate at multiple locations are exhibiting changes (n=5) and all species lacking evidence for association between migration phenology and climate (n=3) exhibit no change. Migrants tend to arrive earlier in association with warmer temperatures, positive NAO indices, and stronger ENSO indices. Twelve species negatively correlate (P≤0.05) with local or regional temperature at least at one location; five species negatively correlate with ENSO. Eleven species' arrival is correlated (P≤0.05) with NAO; 10 are negatively associated. After an exhaustive literature search, this is apparently the first documentation of an association between NAO and migratory phenology in western North America.
Compromised CD4+ CD25high regulatory T‐cell function in patients with relapsing‐remitting multiple sclerosis is correlated with a reduced frequency of FOXP3‐positive cells and reduced FOXP3 expression at the single‐cell level
Authors: Venken Koen , Hellings Niels , Thewissen Marielle , Somers Veerle , Hensen Karen , Rummens Jean‐Luc , Medaer Robert , Hupperts Raymond , Stinissen Piet 
Published: September 2007

SummaryCD4+ CD25high regulatory T cells (Tregs) of patients with relapsing‐remitting (RR) multiple sclerosis (MS), in contrast to those of patients with secondary progressive (SP) MS, show a reduced suppressive function. In this study, we analysed forkhead box P3 (FOXP3) at the single‐cell level in MS patients and controls (healthy individuals and patients with other neurological diseases) by means of intracellular flow cytometry. Our data revealed a reduced number of peripheral blood CD4+ CD25high FOXP3+ T cells and lower FOXP3 protein expression per cell in RR‐MS patients than in SP‐MS patients and control individuals, which was correlated with the suppressive capacity of Tregs in these patients. Interestingly, interferon (IFN)‐β‐treated RR‐MS patients showed restored numbers of FOXP3+ Tregs. Furthermore, a higher percentage of CD4+ CD25high FOXP3+ Tregs in RR‐MS patients, as compared with controls and SP‐MS patients, expressed CD103 and CD49d, adhesion molecules involved in T‐cell recruitment towards inflamed tissues. This was consistent with a significantly increased number of CD27+ CD25high CD4+ T cells in the cerebrospinal fluid (CSF), as compared with peripheral blood, in RR‐MS patients. Taken together, these data show aberrant FOXP3 expression at the single‐cell level correlated with Treg dysfunction in RR‐MS patients. Our results also suggest that Tregs accumulate in the CSF of RR‐MS patients, in an attempt to down‐regulate local inflammation in the central nervous system.
Induction of 150‐kDa adenosine deaminase that acts on RNA (ADAR)‐1 gene expression in normal T lymphocytes by anti‐CD3‐ε and anti‐CD28
Authors: Laxminarayana Dama , Khan Islam U. , O'Rourke Kenneth S. , Giri Banabihari 
Published: September 2007

SummaryWe and other investigators have demonstrated up‐regulation of the expression of the RNA‐editing gene 150‐kDa adenosine deaminase that acts on RNA (ADAR1) in systemic lupus erythematosus (SLE) T cells and B cells, peripheral blood mononuclear cells (PBMC), natural killer (NK) cells. The presence of a small proportion of activated T cells is the hallmark of SLE. Therefore, it was hypothesized that 150‐kDa ADAR1 gene expression is induced by the physiological activation of T cells. To examine this hypothesis, normal T cells were activated by anti‐CD3‐ε plus anti‐CD28 for various time periods from 0 to 48 hr. The expression of 110‐kDa and 150‐kDa ADAR1, and interleukin (IL)‐2 and β‐actin gene transcripts was analysed. An approximately fourfold increase in 150‐kDa ADAR1 gene expression was observed in activated T cells. ADAR2 gene transcripts are substrates for ADAR1 and ADAR2 enzymes. Therefore, we assessed the role of the 150‐kDa ADAR enzyme in editing of ADAR2 gene transcripts. In activated T cells, site‐selective editing of the −2 site was observed. Previous studies indicate that this site is predominantly edited by ADAR1. In addition to this, novel editing sites at base positions −56, −48, −45, −28, −19, −15, +46 and +69 were identified in activated T cells. On the basis of these results, it is proposed that 150‐kDa ADAR1 gene expression is selectively induced in T cells by anti‐CD3‐ε and anti‐CD28 stimulation and that it may play a role in site‐selective editing of gene transcripts and in altering the functions of several gene products of T cells during activation and proliferation.
The zinc cluster transcription factor Tac1p regulates PDR16 expression in Candida albicans
Authors: Znaidi Sadri , De Deken Xavier , Weber Sandra , Rigby Tracey , Nantel André , Raymond Martine 
Published: September 2007

SummaryThe Candida albicans PDR16 gene, encoding a putative phosphatidylinositol transfer protein, is co‐induced with the multidrug transporter genes CDR1 and CDR2 in azole‐resistant (AR) clinical isolates and upon fluphenazine exposure of azole‐susceptible (AS) cells, suggesting that it is regulated by Tac1p, the transcriptional activator of CDR genes. Deleting TAC1 in an AR isolate (5674) overexpressing PDR16, CDR1 and CDR2 decreased the expression of the three genes and fluconazole resistance to levels similar to those detected in the matched AS isolate (5457), demonstrating that Tac1p is responsible for PDR16 upregulation in that strain. Deleting TAC1 in the AS strain SC5314 abolished CDR2 induction by fluphenazine and decreased that of PDR16 and CDR1, uncovering the participation of an additional factor in the regulation of PDR16 and CDR1 expression. Sequencing of the TAC1 alleles identified one homozygous mutation in strain 5674, an Asn to Asp substitution at position 972 in the C‐terminus of Tac1p. Introduction of the Asp972 allele in a tac1Δ/Δ mutant caused high levels of fluconazole resistance and TAC1, PDR16, CDR1 and CDR2 constitutive induction. These results demonstrate that: (i) Tac1p controls PDR16 expression; (ii) Asn972 to Asp972 is a gain‐of‐function mutation; and (iii) Tac1p is positively autoregulated, directly or indirectly.
Elaborate spatial patterning of cell‐wall PME and PMEI at the pollen tube tip involves PMEI endocytosis, and reflects the distribution of esterified and de‐esterified pectins
Authors: Röckel Nina , Wolf Sebastian , Kost Benedikt , Rausch Thomas , Greiner Steffen 
Published: September 2007

SummaryIn dicots, pectins are the major structural determinant of the cell wall at the pollen tube tip. Recently, immunological studies revealed that esterified pectins are prevalent at the apex of growing pollen tubes, where the cell wall needs to be expandable. In contrast, lateral regions of the cell wall contain mostly de‐esterified pectins, which can be cross‐linked to rigid gels by Ca2+ ions. In pollen tubes, several pectin methylesterases (PMEs), enzymes that de‐esterify pectins, are co‐expressed with different PME inhibitors (PMEIs). This raises the possibility that interactions between PMEs and PMEIs play a key role in the regulation of cell‐wall stability at the pollen tube tip. Our data establish that the PME isoform AtPPME1 (At1g69940) and the PMEI isoform AtPMEI2 (At3g17220), which are both specifically expressed in Arabidopsis pollen, physically interact, and that AtPMEI2 inactivates AtPPME1 in vitro. Furthermore, transient expression in tobacco pollen tubes revealed a growth‐promoting activity of AtPMEI2, and a growth‐inhibiting effect of AtPPME1. Interestingly, AtPPME1:YFP accumulated to similar levels throughout the cell wall of tobacco pollen tubes, including the tip region, whereas AtPMEI2:YFP was exclusively detected at the apex. In contrast to AtPPME1, AtPMEI2 localized to Brefeldin A‐induced compartments, and was found in FYVE‐induced endosomal aggregates. Our data strongly suggest that the polarized accumulation of PMEI isoforms at the pollen tube apex, which depends at least in part on local PMEI endocytosis at the flanks of the tip, regulates cell‐wall stability by locally inhibiting PME activity.
Glycated albumin levels predict long‐term survival in diabetic patients undergoing haemodialysis
Authors: FUKUOKA KOUSUKE , NAKAO KAZUSHI , MORIMOTO HISANORI , NAKAO AI , TAKATORI YUJI , ARIMOTO KATSUHIKO , TAKI MASAFUMI , WADA JUN , MAKINO HIROFUMI 
Published: September 2007

SUMMARY:Aim:  Glycated albumin (GA) is recognized as a reliable marker for monitoring glycemic control particularly in patients with end‐stage renal disease (ESRD). Here, we investigated the impact of GA levels on long‐term survival in diabetic patients with ESRD.Methods:  We enrolled ESRD patients with diabetic nephropathy into our single‐centre prospective follow‐up study (n = 98, 66 men and 32 women; age 68.2  12.3 years) with a mean follow‐up period of 47.7 months. All patients had started haemodialysis between December 1992 and November 2003. They were categorized into two groups according to their GA levels at the initiation of haemodialysis; GA < 29% (low‐GA group; n = 54) and GA  29% (high‐GA group; n = 44).Results:  Between low‐GA and high‐GA groups, there were no significant differences in various clinical parameters except GA and HbA1c levels. The cumulative survival rate of low‐GA group was significantly higher than that of high‐GA group (P = 0.034, log–rank test). After adjustment for age, sex, total cholesterol, C‐reactive protein and albumin, high‐GA was a significant predictor of survival (hazard ratio 1.042 per 1.0% increment of GA, 95% CI 1.014–1.070, P < 0.05), but not in the case with HbA1c. Cox proportional hazard model demonstrated that high‐GA group was a significant predictor for cardiovascular death (hazard ratio 2.971 (1.064–8.298), P = 0.038).Conclusion:  We conclude that poor glycemic control (GA  29%) before starting haemodialysis is associated with increased cardiovascular morbidity and shortened survival in diabetic patients with ESRD.