bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ascospore Formation in the YeastSaccharomyces cerevisiae
Authors: Neiman Aaron M. 
Published: December 2005

SUMMARYSporulation of the baker's yeastSaccharomyces cerevisiaeis a response to nutrient depletion that allows a single diploid cell to give rise to four stress-resistant haploid spores. The formation of these spores requires a coordinated reorganization of cellular architecture. The construction of the spores can be broadly divided into two phases. The first is the generation of new membrane compartments within the cell cytoplasm that ultimately give rise to the spore plasma membranes. Proper assembly and growth of these membranes require modification of aspects of the constitutive secretory pathway and cytoskeleton by sporulation-specific functions. In the second phase, each immature spore becomes surrounded by a multilaminar spore wall that provides resistance to environmental stresses. This review focuses on our current understanding of the cellular rearrangements and the genes required in each of these phases to give rise to a wild-type spore.
Comparative Genomic Analyses of the Bacterial Phosphotransferase System
Authors: Barabote Ravi D. , Saier Milton H. 
Published: December 2005

SUMMARY
We
report analyses of 202 fully sequenced genomes for homologues of known
protein constituents of the bacterial phosphoenolpyruvate-dependent
phosphotransferase system (PTS). These included 174 bacterial, 19
archaeal, and 9 eukaryotic genomes. Homologues of PTS proteins were not
identified in archaea or eukaryotes, showing that the horizontal
transfer of genes encoding PTS proteins has not occurred between the
three domains of life. Of the 174 bacterial genomes (136 bacterial
species) analyzed, 30 diverse species have no PTS homologues, and 29
species have cytoplasmic PTS phosphoryl transfer protein homologues but
lack recognizable PTS permeases. These soluble homologues presumably
function in regulation. The remaining 77 species possess all PTS
proteins required for the transport and phosphorylation of at least one
sugar via the PTS. Up to 3.2% of the genes in a bacterium encode PTS
proteins. These homologues were analyzed for family association, range
of protein types, domain organization, and organismal distribution.
Different strains of a single bacterial species often possess
strikingly different complements of PTS proteins. Types of PTS protein
domain fusions were analyzed, showing that certain types of domain
fusions are common, while others are rare or prohibited. Select PTS
proteins were analyzed from different phylogenetic standpoints, showing
that PTS protein phylogeny often differs from organismal phylogeny. The
results document the frequent gain and loss of PTS protein-encoding
genes and suggest that the lateral transfer of these genes within the
bacterial domain has played an important role in bacterial evolution.
Our studies provide insight into the development of complex
multicomponent enzyme systems and lead to predictions regarding the
types of protein-protein interactions that promote efficient
PTS-mediated phosphoryl transfer.
Coronavirus Pathogenesis and the Emerging Pathogen Severe Acute Respiratory Syndrome Coronavirus
Authors: Weiss Susan R. , Navas-Martin Sonia 
Published: December 2005

SUMMARYCoronaviruses are a family of enveloped, single-stranded, positive-strand RNA viruses classified within the Nidovirales order. This coronavirus family consists of pathogens of many animal species and of humans, including the recently isolated severe acute respiratory syndrome coronavirus (SARS-CoV). This review is divided into two main parts; the first concerns the animal coronaviruses and their pathogenesis, with an emphasis on the functions of individual viral genes, and the second discusses the newly described human emerging pathogen, SARS-CoV. The coronavirus part covers (i) a description of a group of coronaviruses and the diseases they cause, including the prototype coronavirus, murine hepatitis virus, which is one of the recognized animal models for multiple sclerosis, as well as viruses of veterinary importance that infect the pig, chicken, and cat and a summary of the human viruses; (ii) a short summary of the replication cycle of coronaviruses in cell culture; (iii) the development and application of reverse genetics systems; and (iv) the roles of individual coronavirus proteins in replication and pathogenesis. The SARS-CoV part covers the pathogenesis of SARS, the developing animal models for infection, and the progress in vaccine development and antiviral therapies. The data gathered on the animal coronaviruses continue to be helpful in understanding SARS-CoV.
Cysteine-rich protein 1 (CRP1) regulates actin filament bundling
Authors: Tran Thuan C , Singleton CoreyAyne , Fraley Tamara S , Greenwood Jeffrey A 
Published: December 2005

Abstract

Background
Cysteine-rich protein 1 (CRP1) is a LIM domain containing protein localized to the nucleus and the actin cytoskeleton. CRP1 has been demonstrated to bind the actin-bundling protein α-actinin and proposed to modulate the actin cytoskeleton; however, specific regulatory mechanisms have not been identified.

Results
CRP1 expression increased actin bundling in rat embryonic fibroblasts. Although CRP1 did not affect the bundling activity of α-actinin, CRP1 was found to stabilize the interaction of α-actinin with actin bundles and to directly bundle actin microfilaments. Using confocal and photobleaching fluorescence resonance energy transfer (FRET) microscopy, we demonstrate that there are two populations of CRP1 localized along actin stress fibers, one associated through interaction with α-actinin and one that appears to bind the actin filaments directly. Consistent with a role in regulating actin filament cross-linking, CRP1 also localized to the membrane ruffles of spreading and PDGF treated fibroblasts.

Conclusion
CRP1 regulates actin filament bundling by directly cross-linking actin filaments and stabilizing the interaction of α-actinin with actin filament bundles.
Accuracy of clinical pallor in the diagnosis of anaemia in children: a meta-analysis
Authors: Chalco Juan P , Huicho Luis , Alamo Carlos , Carreazo Nilton Y , Bada Carlos A 
Published: December 2005

AbstractBackgroundAnaemia is highly prevalent in children of developing countries. It is associated with impaired physical growth and mental development. Palmar pallor is recommended at primary level for diagnosing it, on the basis of few studies. The objective of the study was to systematically assess the accuracy of clinical signs in the diagnosis of anaemia in children.MethodsA systematic review on the accuracy of clinical signs of anaemia in children. We performed an Internet search in various databases and an additional reference tracking. Studies had to be on performance of clinical signs in the diagnosis of anaemia, using haemoglobin as the gold standard. We calculated pooled diagnostic likelihood ratios (LR's) and odds ratios (DOR's) for each clinical sign at different haemoglobin thresholds.ResultsEleven articles met the inclusion criteria. Most studies were performed in Africa, in children underfive. Chi-square test for proportions and Cochran Q for DOR's and for LR's showed heterogeneity. Type of observer and haemoglobin technique influenced the results. Pooling was done using the random effects model. Pooled DOR at haemoglobin <11 g/dL was 4.3 (95% CI 2.6–7.2) for palmar pallor, 3.7 (2.3–5.9) for conjunctival pallor, and 3.4 (1.8–6.3) for nailbed pallor. DOR's and LR's were slightly better for nailbed pallor at all other haemoglobin thresholds. The accuracy did not vary substantially after excluding outliers.ConclusionThis meta-analysis did not document a highly accurate clinical sign of anaemia. In view of poor performance of clinical signs, universal iron supplementation may be an adequate control strategy in high prevalence areas. Further well-designed studies are needed in settings other than Africa. They should assess inter-observer variation, performance of combined clinical signs, phenotypic differences, and different degrees of anaemia.
C.35delG/ GJB2 and del(GJB6-D13S1830) mutations in Croatians with prelingual non-syndromic hearing impairment
Authors: Medica Igor , Rudolf Gorazd , Balaban Manuela , Peterlin Borut 
Published: December 2005

Abstract

Background
C.35delG/GJB2 mutation is the most frequent genetic cause of deafness in Caucasians. Another frequent mutation in some Caucasian populations is del(GJB6-D13S1830). Both GJB2 and GJB6 genes belong to the same DFNB1 locus and when the two mutations are found in combination in a hearing-impaired person, a digenic pattern of inheritance is suggested.

Methods
We examined 63 Croatian subjects (25 familial and 38 sporadic cases) with prelingual non-syndromic hearing impairment by polymerase chain reaction for the presence of the c.35delG/GJB2 and the del(GJB6-D13S1830) mutations.

Results
Of the 63 unrelated hearing-impaired subjects, the mutation c.35delG/GJB2 was found in 21 subjects (33.3%). In 5 of them the mutation was found in the heterozygous state, all of them being compound heterozygotes, as sequencing revealed a second mutation within the coding region of the gene in 3 subjects, and a splice site mutation in 2 subjects. The del(GJB6-D13S1830) mutation was not found in the investigated hearing-impaired Croatian subjects.

Conclusion
Our results contribute to the knowledge of geographic distribution and population genetics of the GJB2 and GJB6 mutations in the Europeans.
Predicting Sliding Wear Behaviour of a Tin-Based White Metal Under Varying Pressure and Speed Conditions
Authors: Tachi Y , Ishihara S , Tamura K , Goshima T , McEvily A. J. 
Published: December 2005

To determine the effects of loading on the sliding wear behaviour of a tin-based white bearing metal JIS WJ2, experiments were performed over a range of pressures and speeds. A linear relation between stress and cut-off life was obtained on the log-log plot at constant shaft speed. These relations were expressed as different straight lines on the log-log plot, which depend on the shaft speed. However, there is a unique curve in the relation, frictional stress versus cut-off life, regardless of the shaft speeds. To establish a quantitative method of analysing the steady-state sliding wear mode, the following constitutive relation was proposed d w/d N = A(τ – τth)2 where w is the amount of wear, N the number of shaft rotations, A the material constant, τ the interfacial shear stress, and τth the threshold level for wear damage. The aforementioned equation has been used as a basis for estimating wear life. Good agreement between the predictions and the experimental results was obtained.
Effect of Visible Light on Normal and P23H‐3 Transgenic Rat Retinas: Characterization of a Novel Retinoic Acid Derivative Present in the P23H‐3 Retina
Authors: Duncan Todd , Wiggert Barbara , Whittaker Noel , Darrow Ruth , Organisciak Daniel T. 
Published: December 2005

ABSTRACTTransgenic rats with the P23H mutation in rhodopsin exhibit increased susceptibility to light damage, compared with normal animals. It is known that light‐induced retinal damage requires repetitive bleaching of rhodopsin and that photoreceptor cell loss is by apoptosis; however, the underlying molecular mechanism(s) leading to photoreceptor cell death are still unknown. Photoproducts, such as all‐trans retinal or other retinoid metabolites, released by the extensive bleaching of rhodopsin could lead to activation of degenerative processes, especially in animals genetically predisposed to retinal degenerations. Using wild‐type and transgenic rats carrying the P23H opsin mutation, we evaluated the effects of acute intense visible light on retinoid content, type and distribution in ocular tissues. Rats were exposed to green light (480–590 nm) for 0, 5, 10, 30 and 120 min. Following light treatment, rats were sacrificed and neural retinas were dissected free of the retinal pigment epithelium. Retinoids were extracted from retinal tissues and then subjected to HPLC and mass spectral analysis. We found that the light exposure affected relative levels of retinoids in the neural retina and retinal pigment epithelium of wild‐type and P23H rat eyes similarly. In the P23H rat retina but not the wild‐type rat retina, we found a retinoic acid‐like compound with an absorbance maximum of 357 nm and a mass of 304 daltons. Production of this retinoic acid‐like compound in transgenic rats is influenced by the age of the animals and the duration of light exposure. It is possible that this unique retinoid may be involved in the process of light‐induced retinal degeneration.
Effects of Organic Fertilization and Organic Diets on Production of Channel Catfish in Earthen Ponds
Authors: Li Menghe H , Robinson Edwin H , Mischke Charles C , Torrans Eugene L , Bosworth Brian G 
Published: December 2005

Abstract
We evaluated the effects of organic fertilization and “organic” diets on the production of channel catfish Ictalurus punctatus. During fingerling production, four 0.4-ha earthen ponds were fertilized with a combination of inorganic fertilizers and regular cottonseed meal (control ponds) and four were fertilized with organically produced cottonseed meal only (organic ponds). Swim-up fry were stocked into each pond at a rate of 247,000 fish/ha and fed a control or organic diet daily to apparent satiation for one growing season. During food fish production, overwintered control and organic fingerlings (mean initial weights = 50.8 and 44.8 g/fish, respectively) from fingerling production were each stocked into five 0.04-ha ponds at a rate of 14,800 fish/ha and fed a control or organic diet daily to apparent satiation for one growing season. Fish were raised with a predetermined organic program that was largely based on U.S. livestock organic standards, since there were no organic aquaculture standards available in the USA. During fingerling production, ponds fertilized with a combination of inorganic fertilizers and cottonseed meal had higher total N and P and higher abundances of preferred zooplankton taxa than did ponds fertilized with organically produced and processed cottonseed meal alone. Gross production of fingerlings in organic ponds was lower than that in the control ponds. During food fish production, there were no differences in production characteristics and carcass yield between conventionally and organically grown fish. However, organic fish had lower fillet yield and higher body fat than did control fish. The slightly higher body fat observed in organic fish mainly resulted from the slightly higher fat content in the organic diet. The results from this study indicate that channel catfish can be grown from swim-up fry to food size organically, but gross production during the first season may be lower in organic ponds than in nonorganic ponds, in part because preferred zooplankton taxa are produced in lower abundances in the ponds fertilized with organic cottonseed meal.
Evidence of Delayed Mortality on Juvenile Pacific Salmon Passing through Turbines at Columbia River Dams
Authors: Ferguson John W. , Absolon Randall F. , Carlson Thomas J. , Sandford Benjamin P. 
Published: December 2005

AbstractWe evaluated the survival of juvenile salmon through turbines in Columbia River dams and found no differences between two operations but strong evidence of delayed mortality from turbine passage. After tagging with a passive integrated transponder (PIT) tag and a radio tag, yearling Chinook salmon Oncorhynchus tshawytscha were released at McNary Dam on the Columbia River through a turbine operating both within 1% of peak efficiency (a discharge rate of 317 m3/s) and outside the 1% range at the maximum blade angle (464 m3/s). Estimated relative survival to a detection array 15 km downstream was 0.871 at 317 m3/s and 0.856 at 464 m3/s and 0.858 and 0.814, respectively, to an array 46 km downstream. The highest point estimates of survival occurred under the lower discharge, suggesting that operating turbines within 1% of peak efficiency is a useful guideline for fish protection at McNary Dam. In a concurrent evaluation using balloon tags, estimated mean direct survival ranged from 0.930 to 0.946. Radio tag estimates were significantly lower than balloon tag estimates under both operations. Based on these differences, we estimated that delayed mortality comprised from 46% to 70% of total estimated mortality. We reviewed the literature and concluded that delayed mortality was caused by sublethal impacts to fish sensory systems, which increased vulnerability to predation in the tailrace. We recommend that future research to improve turbine designs and operations for fish passage focus on this major component of mortality.
Introducing Bulky Functional Lanthanide Cores into Thermotropic Metallomesogens: A Bottom‐Up Approach
Authors: Terazzi E. , Suarez S. , Torelli S. , Nozary H. , Imbert D. , Mamula O. , Rivera J.‐P. , Guillet E. , Bénech J.‐M. , Bernardinelli G. , Scopelliti R. , Donnio B. , Guillon D. , Bünzli J.‐C. G. , Piguet C. 
Published: December 2005

AbstractBasic thermodynamic considerations are used to rationalize the formation of thermotropic mesophases incorporating aromatic ligands for trivalent lanthanide metal ions (Ln). Standard flat and bent molecular interfaces, separating the central binding unit from the lateral, flexible alkoxy chains, provide programmed lamellar and columnar organization in the mesophases, which are removed upon complexation to Ln(NO3)3and Ln(CF3CO2)3. Only significantly curved aromatic/aliphatic interfaces, found in polycatenar ligands, are able to overcome the considerable perturbations of the intermolecular interactions produced by the introduction of the bulky metallic core. A rich mesomorphism results, which can be tuned by a judicious control of the metallic coordination sphere. The exploitation of specific, metal‐centered luminescence for probing phase transitions and microscopic environments in mesophases is also discussed, as is the use of ionic liquids for producing tunable luminescent mesophases.
Biosensing Properties of TitanateNanotube Films: Selective Detection of Dopamine in the Presence of Ascorbate and Uric Acid
Authors: Liu A. , Wei M. D. , Honma I. , Zhou H. 
Published: December 2005

AbstractA novel strategy based on titanate nanotubes (TNTs) for developing an electrochemical biosensor is proposed. Stable TNT films are fabricated on glassy carbon (GC) electrodes by a casting technique. Cyclic voltammetry, electrochemical impedance spectrometry, and linear‐sweep voltammetry are used to characterize the TNT membrane‐covered GC electrodes (TNT/GCs). The TNT film is shown to demonstrate selectivity by charge exclusion. The TNT film is also shown to be capable of improving the mass transport to the electrode surface and electron transfer between dopamine (DA) and the electrode. Therefore, DA exhibits a quasireversible electrochemical reaction at the TNT/GC electrode. The voltammetric signal of DA is well resolved from those of ascorbate (AA) and uric acid (UA) at the TNT/GC electrode; therefore, DA can be selectively detected in the presence of a large excess of AA and UA at physiological pH. The linear calibration curve for DA is obtained over the concentration range 0.1–30 μM in a physiological solution that contains 0.1 mM AA and 0.3 mM UA.
Fabrication of Single‐Crystalline Silicon Nanowires by Scratching a Silicon Surface with Catalytic Metal Particles
Authors: Peng K. Q. , Hu J. J. , Yan Y. J. , Wu Y. , Fang H. , Xu Y. , Lee S. T. , Zhu J. 
Published: December 2005

AbstractA novel strategy for preparing large‐area, oriented silicon nanowire (SiNW) arrays on silicon substrates at near room temperature by localized chemical etching is presented. The strategy is based on metal‐induced (either by Ag or Au) excessive local oxidation and dissolution of a silicon substrate in an aqueous fluoride solution. The density and size of the as‐prepared SiNWs depend on the distribution of the patterned metal particles on the silicon surface. High‐density metal particles facilitate the formation of silicon nanowires. Well‐separated, straight nanoholes are dug along the Si block when metal particles are well dispersed with a large space between them. The etching technique is weakly dependent on the orientation and doping type of the silicon wafer. Therefore, SiNWs with desired axial crystallographic orientations and doping characteristics are readily obtained. Detailed scanning electron microscopy observations reveal the formation process of the silicon nanowires, and a reasonable mechanism is proposed on the basis of the electrochemistry of silicon and the experimental results.
On‐Chain Fluorenone Defect Emission from Single Polyfluorene Molecules in the Absence of Intermolecular Interactions
Authors: Becker K. , Lupton J. M. , Feldmann J. , Nehls B. S. , Galbrecht F. , Gao D. Q. , Scherf U. 
Published: December 2005

AbstractThe emission of semiconducting polyfluorenes is often accompanied by an undesired feature in the green spectral region. Whereas a number of previous investigations have argued in favor of a monomolecular origin of the emission species based on ketonic defects, recent experimental results suggested the necessity of excimer formation between individual fluorenone units. We provide a range of new evidence supporting the monomolecular origin of green band emission in polyfluorenes. Most importantly, we succeed in performing single‐molecule spectroscopy on fluorenone‐containing polyfluorene model compounds. Whereas most fluorenone‐containing molecules exhibit both blue backbone and green fluorenone emission independent of fluorenone concentration, it is the relative intensities of the two species which correlate strongly with the fluorenone concentration on the single‐molecule level. Furthermore, we consider a novel model compound with a bifacial arrangement of two fluorenone units. This compound does not provide any signatures of enhanced intramolecular excimer formation but does strongly indicate that concentration quenching effects occur once fluorenone units can interact electronically. The ability to detect on‐chain defect emission in a single polymer molecule demonstrates that photochemical reactions in conjugated polymers can be monitored by fluorescence spectroscopy down to the level of a few atoms, constituting an unprecedented degree of materials characterization.
Structure and property relationship of thermotropic liquid crystal polymer and polyester composite fibers
Authors: Kim Jun Young , Kim Seong Hun 
Published: December 2005

AbstractPoly(ethylene 2,6‐naphthalate) (PEN) and poly(ethylene terephthalate) (PET) composite fibers reinforced with a thermotropic liquid crystal polymer (TLCP) were prepared by the melt blending and spinning process to achieve high performance fibers with improved processability. Polymer composite fibers consisting of cheap polyester and small quantity of expensive TLCP are of interest from an economic point of view and from an industrial perspective. The increase in the birefringence and density of the TLCP/PEN/PET composite fibers with the spinning speed was attributable to the enhancement of the molecular orientation and effective packing between chains in the TLCP/PEN/PET composite fibers. Annealing process resulted in the formation of more ordered and perfect crystalline structure and higher crystallinity, improving the mechanical properties of the TLCP/PEN/PET composite fibers. The increase in the crystallite size and the degree of chain extension with increasing spinning speed resulted in the gradual increment of the long period for the TLCP/PEN/PET composite fibers. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci, 2006.