bluuebunny/crossref_metadata_2025 huggingface dataset:
Monoamine oxidase A (MAOA) and antisocial behaviors in the presence of childhood and adolescent maltreatment
Authors: Haberstick Brett C. , Lessem Jeffrey M. , Hopfer Christian J. , Smolen Andrew , Ehringer Marissa A. , Timberlake David , Hewitt John K.
Published: April 2005

There is a robust relationship between the experience of maltreatment in childhood and later antisocial behaviors amongst adolescents and adults. Animal and human studies suggest that variation in monoamine oxidase A (MAOA) genotype may moderate the effects of maltreatment. Self‐reported conduct problems and criminal convictions amongst sibling‐pairs from the National Longitudinal Study of Adolescent Health were tested for association with reports of maltreatment before and after the age of 12. MAOA promoter polymorphisms were tested for possible moderation effects. Maltreatment predicted conduct problems and criminal convictions. MAOA genotype did not have a significant moderating effect in any of the six analyses that were conducted. We did not replicate a previous report that MAOA polymorphisms moderated the relationship between maltreatment and conduct problems. There was, however, a non‐significant trend in the predicted direction. Additional studies will be needed before firm conclusions can be drawn about this hypothesized genotype–environment interaction. © 2005 Wiley‐Liss, Inc.
Genome‐wide linkage analyses of extended Utah pedigrees identifies loci that influence recurrent, early‐onset major depression and anxiety disorders
Authors: Camp Nicola J. , Lowry Michael R. , Richards R. Lynn , Plenk Agnes M. , Carter Catherine , Hensel Charles H. , Abkevich Victor , Skolnick Mark H. , Shattuck Donna , Rowe Kerry G. , Hughes Dana C. , Cannon‐Albright Lisa A.
Published: April 2005

Major depressive disorder (MDD) is a common, clinically heterogeneous disorder often found comorbid with other disorders. We studied recurrent, early‐onset MDD (MDD‐RE) and anxiety disorders in combination to define powerful phenotypes for genetic study. We used 87 large, extended Utah pedigrees to investigate linkage to 3 phenotypes: “MDD‐RE;” “MDD‐RE or anxiety;” and “MDD‐RE and anxiety;” where in the latter definition the disorders must appear comorbid within an individual. Pedigrees ranged in size from 2 to 6 generations and contained 3 to 42 individuals affected with MDD or anxiety (718 total). In primary analyses, we identified three regions with at least suggestive genome‐wide evidence for linkage on chromosomes 3centr, 7p, and 18q. Both 7p and 18q are replication findings for related phenotypes. The best linkage evidence was for a novel locus at 3p12.3‐q12.3 (LOD = 3.88, “MDD‐RE or anxiety”) and 18q21.33‐q22.2 (LOD = 3.75, “MDD‐RE and anxiety”), a well‐established susceptibility locus for bipolar disorder. In our secondary sex‐specific analyses, we identified two further regions of interest on chromosomes 4q and 15q. Using linked pedigrees, we localized 3centr and 18q to 9.8 and 12.2 cM, respectively, with potential for further localization with the addition of markers in specific pedigrees. Our success in replication and novel locus identification illustrates the utility of large extended pedigrees for common disorders, such as MDD. Further, it supports the hypothesis that MDD and anxiety disorders have over‐lapping genetic etiologies and suggests that comorbid diagnoses may be useful in defining more genetically homogeneous forms of MDD for linkage mapping. © 2005 Wiley‐Liss, Inc.
Hyperhomocysteinemia, methylenetetrahydrofolate reductase 677TT genotype, and the risk for schizophrenia: A dutch population based case‐control study
Authors: Muntjewerff Jan‐Willem , Hoogendoorn Mechteld L.C. , Kahn René S. , Sinke Richard J. , Heijer Martin Den , Kluijtmans Leo A.J. , Blom Henk J.
Published: April 2005

Evidence for an involvement of aberrant homocysteine metabolism in the aetiology of schizophrenia is limited and controversial. A case‐control study was performed to quantify the risk of schizophrenia in the presence of elevated homocysteine concentrations or homozygosity for the 677C → T polymorphism (677TT) in the methylenetetrahydrofolate reductase (MTHFR) gene in subjects of Dutch ancestry. We determined the 677C → T MTHFR genotype distribution in 254 well‐defined patients and 414 healthy controls. Plasma homocysteine concentrations were measured in 62 patients with schizophrenia and 432 control subjects. When homocysteine concentrations were stratified into quartiles of the control distribution, we calculated an increased risk for schizophrenia in the fourth and third quartile versus the lowest quartile [odds ratio (OR) = 3.3; 95% confidence interval (CI): 1.2–9.2, and OR = 3.1; 95% CI: 1.2–8.0, respectively]. A significant dose‐response relation of increasing homocysteine levels and increasing risk for schizophrenia was observed (P = 0.036). The 677TT genotype was associated with an OR of 1.6 [95% CI: 0.96–2.8] of having schizophrenia. Heterozygosity for the T allele compared to 677CC subjects accounted for an OR of 1.3 [95% CI: 0.91–1.8]. Elevated homocysteine levels and the MTHFR 677TT genotype are associated with an increased risk for schizophrenia. These observations support a causal relation between disturbed homocysteine metabolism and schizophrenia. © 2005 Wiley‐Liss, Inc.
Embryology of neural tube development
Authors: Sadler T.W.
Published: April 2005

Neurulation is the process of forming the neural tube, which will become the brain and spinal cord. This article reviews the various cellular processes involved in neurulation and discusses possible roles of folate in this process. © 2005 Wiley‐Liss, Inc.
Cranial base angulation and growth of the human fetal pharynx
Authors: Jeffery Nathan
Published: April 2005

The upper airway controls the mechanisms of breathing, swallowing, and vocalization. Information on its normal ontogenetic associations is therefore crucial for understanding human speech evolution as well as the developmental etiology of speech abnormalities. Of particular interest to evolutionary morphologists is the proposed structural association between the upper airway and the cranial base. The present study aims to elucidate whether cranial base angulation is linked to growth of the upper airway during human fetal life. Forty postmortem human fetuses ranging from 10 to 29 weeks of gestation were imaged with high‐resolution magnetic resonance imaging. Measurements of basicranial angle, hyoid depth, hormion height, and pharyngeal area were taken from sagittal images. Results show a significant correlation between the internal and external basicranial angles but the correlation between relative hyoid depth and internal cranial base angle was not significant. Findings show a significant correlation between increases in the size of the oropharynx relative to the nasopharynx and increases in the internal cranial base angle (retroflexion). These findings give limited support (rrank = 0.46; P < 0.01) for the hypothesis that restructuring of the upper airway underlies basicranial retroflexion during prenatal life. © 2005 Wiley‐Liss, Inc.
Stable production of hyaluronic acid in Streptococcus zooepidemicus chemostats operated at high dilution rate
Authors: Blank Lars M. , McLaughlin Richard L. , Nielsen Lars K.
Published: April 2005

Hyaluronic acid is routinely produced through fermentation of both Group A and C streptococci. Despite significant production costs associated with short fermentations and removal of contaminating proteins released during entry into stationary phase, hyaluronic acid is typically produced in batch rather than continuous culture. The main reason is that hyaluronic acid synthesis has been found to be unstable in continuous culture except at very low dilution rates. Here, we investigated the mechanisms underlying this instability and developed a stable, high dilution rate (0.4 h−1) chemostat process for both chemically defined and complex media operating for more than 150 h of production. In chemically defined medium, the product yield was 25% higher in chemostat cultures than in conventional batch culture when arginine or glucose was the limiting substrate. In contrast, glutamine limitation resulted in higher ATP requirements and a yield similar to that observed in batch culture. In complex, glucose‐limited medium, ATP requirements were greatly reduced but biomass synthesis was favored over hyaluronic acid and no improvement in hyaluronic acid yield was observed. The successful establishment of continuous culture at high dilution rate enables both commercial production at reduced cost and a more rational characterization and optimization of hyaluronic acid production in streptococci. © 2005 Wiley Periodicals, Inc.
Intramolecular Electron Transfer in Nitrite Reductases
Authors: Wherland Scot , Farver Ole , Pecht Israel
Published: April 2005

The copper‐ and heme‐containing nitrite reductases (NiRs) are key enzymes in denitrification. Their subunits contain two distinct redox‐active metal centers, an electron‐accepting site and a nitrite‐reducing site, to carry out the single‐electron reduction of nitrite to nitic oxide. Catalytic cycles of both enzyme families employ intramolecular electron transfer that can be rate‐determining for their activity. Herein, we report results comparing these two enzyme families in order to resolve the different mechanisms controlling intramolecular electron transfer in these proteins.
Stability of (C60)2 and epoxide dimers, (C60)2ON, and their anions
Authors: Owens Frank J.
Published: April 2005

The PM3, AM1, and MINDO3 semiemperical methods are used to calculate the the energy difference between C60ON and C60O and the bond dissociation energy necessary to cleave neutral and negatively charged (C60)2 dimers and epoxide dimers, (C60)2ON, to their respective monomers C60, and C60ON/2. The results show that the anions of the dimers are significantly more stable than neutral dimers. This result may explain the higher thermal stability of the observed ferromagnetic phase in photolyzed C60. which has been attributed to epoxide dimers and oligomers. It also provides an explanation for the origin of unpaired electron spin necessary for ferromagnetism. Published 2005 Wiley Periodicals, Inc. J Comput Chem 26: 803–806, 2005
Preparation of monolithic silica column with strong cation‐exchange stationary phase for capillary electrochromatography
Authors: Xie Chuanhui , Hu Jiwei , Xiao Hua , Su Xingye , Dong Jing , Tian Ruijun , He Zhike , Zou Hanfa
Published: April 2005

A monolithic silica based strong cation‐exchange stationary phase was successfully prepared for capillary electrochromatography. The monolithic silica matrix from a sol‐gel process was chemically modified by treatment with 3‐mercaptopropyltrimethoxysilane followed by a chemical oxidation procedure to produce the desired function. The strong cation‐exchange stationary phase was characterized by its substantial and stable electroosmotic flow (EOF), and it was observed that the EOF value of the prepared column remained almost unchanged at different buffer pH values and slowly decreased with increasing phosphate concentration in the mobile phase. The monolithic silica column with strong cation‐exchange stationary phase has been successfully employed in the electrochromatographic separation of β‐blockers and alkaloids extracted from traditional Chinese medicines (TCMs). The column efficiencies for the tested β‐blockers varied from 210,000 to 340,000 plates/m. A peak compression effect was observed for atenolol with the mobile phase having a low phosphate concentration.
Solid phase micro‐extraction coupled with ion mobility spectrometry for the analysis of ephedrine in urine
Authors: Lokhnauth John K. , Snow Nicholas H.
Published: April 2005

Quantitative solid phase micro‐extraction (SPME) coupled with ion mobility spectrometry is demonstrated using the analysis of ephedrine in urine. Since its inception in the 1970's ion mobility spectrometry (IMS) has evolved into a useful technique for laboratories to detect explosives, chemical warfare agents, environment pollutants and, increasingly, for detecting drugs of abuse. Ephedrine is extracted directly from urine samples using SPME and the analyte on the fiber is heated by the IMS desorber unit and vaporized into the drift tube. The analytical procedure was optimized for fiber coating selection, extraction temperature, extraction time, sample pH, and analyte desorption temperature. The carryover effects, ion fragmentation characteristics, peak shapes, and drift times of ephedrine were also evaluated based on the direct interfacing of SPME to IMS. A limit of detection of 50 ng/mL of ephedrine in urine and a linear range of 3 orders of magnitude were obtained, showing that SPME‐IMS compares well to other techniques for ephedrine and drug analysis presented in the literature.
On interpolation of vector‐valued Banach lattices and Calderón–Lozanovskii construction
Authors: Fan Ming
Published: April 2005

See original Math. Nachr. Bd. 227, 63–80 (2001)
Reply: Huntington's disease and minocycline
Authors: Thomas Madhavi , Ashizawa Tetsuo , Jankovic J.
Published: April 2005

The original letter to which this reply refers was published in Movement DisordersMov Disord (2005) 20 (4) 510–511.
Three‐dimensional stereotactic surface projection SPECT analysis in Parkinson's disease with and without dementia
Authors: Osaki Yasushi , Morita Yukari , Fukumoto Mitsutaka , Akagi Naoki , Yoshida Shoji , Doi Yoshinori
Published: April 2005

We investigated regional cerebral blood flow (rCBF) using three‐dimensional stereotactic surface projection (3D‐SSP) analysis in 30 patients initially diagnosed as Parkinson's disease (PD), and compared differences in rCBF between patients with and without PD‐related manifestations. 3D‐SSP analysis of cerebral perfusion was performed by use of a control database. Compared to age‐matched controls, there were multiple hypoperfusion areas in cases where the original diagnosis was PD. Temporal bases showed the lowest perfusion; frontal bases and medial parietal lobes the second; visual cortices the third; and parietal association areas exhibited the fourth lowest. During the clinical course, 10 of the patients suffered dementia, 9 had fluctuating cognition, and 19 experienced repeated visual hallucinations. Significant negative correlations were observed between dementia and the bilateral posterior cingulate area, and among fluctuating cognition and bilateral medial parietal lobes, parietal association areas, and dorsal occipital lobes. Repeated visual hallucinations did not show any correlation with any region of interest. We concluded that multiple hypoperfusion areas were observed in the 3D‐SSP SPECT analysis. Although the presence of dementia showed a significant relationship with the bilateral posterior cingulate areas, perfusion in the frontal bases, temporal bases, or parietal lobes was markedly more reduced than that seen in the bilateral posterior cingulate areas. © 2005 Movement Disorder Society
Characterization of subclinical tremor in Parkinson's disease
Authors: Beuter Anne , Barbo Emilie , Rigal Robert , Blanchet Pierre J.
Published: April 2005

The physiological or pathological nature of subclinical tremor amplitude in Parkinson's disease (PD) is not well established. We analyzed characteristics of resting and postural tremors of subclinical amplitude in 17 patients with idiopathic PD without visible resting tremor, having a postural tremor in their least‐affected hand rated 0 (12 subjects) or 1 (5 subjects) on Item 21 of the Unified Parkinson's Disease Rating Scale, compared to 17 control subjects matched for age, sex, and handedness. Tremor was recorded at the tip of the index finger using a displacement laser transducer. Overall results show that subclinical resting tremor in PD is significantly different from physiological tremor in terms of amplitude fluctuation, frequency dispersion, harmonic index, and proportional power in 4 to 6 Hz. No significant differences were found for postural tremor. These differences appear to originate mainly from patients with the mixed form of the disease. This study also confirms the preservation of physiological tremor likely originating from a distinct central oscillator in PD. The use of this method in the early and detailed characterization of PD tremors when amplitude is still within normal limits is proposed. © 2005 Movement Disorder Society
Optimization of real time RT‐PCR methods for the analysis of gene expression in mouse eggs and preimplantation embryos
Authors: Jeong Yu‐Jeong , Choi Hye‐Won , Shin Hyeon‐Sang , Cui Xiang‐Shun , Kim Nam‐Hyung , Gerton George L. , Jun Jin Hyun
Published: April 2005

This study was carried out to optimize conditions for using real time RT‐PCR as an efficient and precise quantitative method for estimating the transcript levels of genes expressed in samples containing miniscule amounts of RNA, such as single mammalian oocytes and embryos. First, using mouse eggs and blastocysts, we tested three kinds of RNA isolation or collection methods: TRIZOL reagent, oligo‐dT conjugated beads, or three freeze/thaw cycles with the reverse transcription buffer. There were no significant differences among three groups in mRNA quantity as assayed by real time RT‐PCR analysis. Second, we compared the efficacy of real time analysis between TaqMan fluorescent probes and the SYBR‐green dye system. The two systems presented similar real time RT‐PCR profiles for the 16s ribosomal protein gene from oocytes to blastocysts. Third, RNA from mouse embryos at defined stages of preimplantation development were isolated and the levels of transcripts encoded by several housekeeping genes (GAPDH, β‐actin, ribosomal protein L7, 16s ribosomal protein, histone H2A.Z) were quantitatively analyzed by real time RT‐PCR. The histone H2A.Z and 16s ribosomal protein slightly increased from the egg to blastocyst stages by approximately 10‐ and 30‐fold, respectively. However, other transcripts increased more than 300‐fold as a function of developmental stage from eggs to blastocysts. Our results suggest that the simple freezing/thawing method for RNA collection, the economic SYBR‐green dye system, and histone H2A.Z gene as an internal control should be useful for the real time RT‐PCR analysis of single mouse eggs and preimplantation embryos. Mol. Reprod. Dev. © 2005 Wiley‐Liss, Inc.
Specific maternal transcripts in bovine oocytes and cleavaged embryos: Identification with novel DDRT‐PCR methods
Authors: Hwang Kyu‐Chan , Park Sae‐Young , Park Se‐Pill , Lim Jin Ho , Cui Xiang‐Shun , Kim Nam‐Hyung
Published: April 2005

We used annealing control primer (ACP)‐based differential display reverse transcription polymerase chain reaction (DDRT‐PCR) to isolate differentially expressed amplicons in bovine germinal vesicle (GV) stage oocytes, 8‐cell stage embryos produced in vitro, and blastocyst stage embryos produced in vitro. Four expressed sequence tags (ESTs) of genes that were specifically and predominantly expressed in GV oocytes were cloned and sequenced. We have used a fluorescence monitored real‐time quantitative PCR (qPCR) to quantify and analyzed the temporal expression of the target differentially expressed transcripts throughout the preimplantation stages from oocytes to blastocysts. The cloned genes or ESTs all exhibited significant sequence similarity with known bovine genes (98%–100%; DNCL1 and ZP2) or ESTs (81%–97%; FANK1 and GTL3) of other species. As revealed by real‐time qRT‐PCR, DNCL1, FANK1, GTL3, and ZP2 transcripts were observed in the GV stage oocytes and expression gradually decreased up to the 8‐cell stage embryo and the transcripts were not detected in later stages. Similarly, upregulation was observed in GV stage mouse oocytes and metaphase II, suggesting that these four differentially expressed orthologous genes play important roles in early preimplantation, as maternally‐derived transcripts. Mol. Reprod. Dev. © 2005 Wiley‐Liss, Inc.
Production of α1,3‐galactosyltransferase gene knockout pigs expressing both human decay‐accelerating factor and N‐acetylglucosaminyltransferase III
Authors: Takahagi Yoichi , Fujimura Tatsuya , Miyagawa Shuji , Nagashima Hiroshi , Shigehisa Tamotsu , Shirakura Ryota , Murakami Hiroshi
Published: April 2005

Heterozygous alpha 1,3‐galactosyltransferase (GT) gene knockout pigs were produced with transgenic pig fetal cells expressing both human decay‐accelerating factor (hDAF) and N‐acetylglucosaminyltransferase III (GnT‐III). In this study, we assessed the gene targeting efficiency in the transgenic pig fetal cells derived from different fetal tissues such as brain, skin, heart, and liver, or fetal carcass. Targeted cell colonies were selected by hygromycin B. The GT‐knockout colonies (KO colonies) were obtained equally from the cells derived from all tissues except liver. Staining with five antibodies against intermediate filaments, all examined KO cell lines stained positive for vimentin with the exception of a colony that stained positive for both vimentin and glial fibrillary acidic protein simultaneously. This is the first study to produce KO cells from the astrocytes. Some of these KO cell lines were used for nuclear transfer (NT) to obtain KO pig fetuses. Fourteen fetuses were obtained from two recipients of the embryo transfer and eight of them had normal ploidy. The cells from the KO pig fetuses were also used for NT to produce cloned KO pigs. Two healthy clone pigs were born. These pigs were determined to have a heterozygous knockout GT gene and the two transgenes. The cells collected from the KO pigs were shown to have similar expression levels of hDAF and GnT‐III compared to their original transgenic pigs and less than a half levels of the αGal epitopes existed in wild‐type pig cells. Mol. Reprod. Dev. © 2005 Wiley‐Liss, Inc.
Functional sparing of intrafusal muscle fibers in muscular dystrophies
Authors: Aimonetti Jean‐Marc , Ribot‐Ciscar Edith , Rossi‐Durand Christiane , Attarian Shahram , Pouget Jean , Roll Jean‐Pierre
Published: April 2005

In a previous study, we showed that patients with muscular dystrophies (MDs) perceive passive movements, experience sensations of illusory movement induced by muscle tendon vibration, and have proprioceptive‐regulated sways in response to vibratory stimulation applied to the neck and ankle muscle tendons. These findings argue for preserved proprioceptive functions of muscle spindles. However, it is unclear whether the function of intrafusal muscle fibers is spared, i.e., whether they retain their ability to contract when submitted to a fusimotor drive. To answer this question, we analyzed the effects of reinforcement maneuvers (mental computation and the Jendrassik maneuver) that are known to increase muscle spindle sensitivity via fusimotor drive in healthy subjects. Nine patients with different MDs participated in the study. Reinforcement maneuvers increased both the mean amplitude of the Achilles tendon reflex (187 ± 52.9% of the mean control amplitude) and the sensitivity of muscle spindle afferents to imposed movements of the ankle. The same reinforcement maneuvers failed to alter the amplitude of the Hoffmann reflex in the triceps surae muscle. These results suggest that the intrafusal muscle fibers preserve their contractile abilities in slowly progressive MDs. The reasons for a differential impairment of intrafusal and extrafusal muscle fibers and the clinical implications of the present results are discussed. Muscle Nerve, 2005
Optimization methods for the verification of second order sufficient conditions for bang–bang controls
Authors: Maurer H. , Büskens C. , Kim J.‐H. R. , Kaya C. Y.
Published: April 2005

It has been common practice to find controls satisfying only necessary conditions for optimality, and then to use these controls assuming that they are (locally) optimal. However, sufficient conditions need to be used to ascertain that the control rule is optimal. Second order sufficient conditions (SSC) which have recently been derived by Agrachev, Stefani, and Zezza, and by Maurer and Osmolovskii, are a special form of sufficient conditions which are particularly suited for numerical verification. In this paper we present optimization methods and describe a numerical scheme for finding optimal bang–bang controls and verifying SSC. A straightforward transformation of the bang–bang arc durations allows one to use standard optimal control software to find the optimal arc durations as well as to check SSC. The proposed computational verification technique is illustrated on three example applications. Copyright © 2005 John Wiley & Sons, Ltd.
Preparation and phase behavior of poly(4‐trimethylsilylstyrene)‐block‐polyisoprene
Authors: Harada Masashi , Ohya Masayuki , Suzuki Takahisa , Kawaguchi Daisuke , Takano Atsushi , Matsushita Yushu
Published: April 2005

Three poly(4‐trimethylsilylstyrene)‐block‐polyisoprenes (TIs), the molecular weights of which were 82,000, 152,000 and 291,000 (TI‐82K, TI‐152K, and TI‐291K), were synthesized by sequential anionic polymerizations. The component polymers were a miscible pair that presented a lower critical solution temperature phase diagram if blended. The TI phase behavior was investigated with transmission electron microscopy. The order–disorder transition could be observed at a temperature between 200 °C (the ordered state) and 150 °C (the disordered state) for the block copolymer TI‐152K. The block copolymer TI‐82K presented the disordered state at 200 °C, whereas TI‐291K was in the ordered state at 150 °C. With the Flory–Huggins interaction parameter between poly(4‐trimethylsilylstyrene) and polyisoprene, which was evaluated by small‐angle neutron scattering for the block copolymers, the TI phase behavior could be reasonably explained by mean‐field theory. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1214–1219, 2005
Correlation between cough frequency and airway inflammation in children with primary ciliary dyskinesia
Authors: Zihlif Nadwa , Paraskakis Emmanouil , Lex Christiane , Van De Pohl Lauri‐Ann , Bush Andrew
Published: April 2005

Cough is common in airway disease. We measured cough frequency in children with primary ciliary dyskinesia (PCD), to determine how accurately families assess this symptom; and to assess the relationship between cough frequency and airway inflammation, measured using induced sputum and exhaled nitric oxide (eNO). Twenty stable PCD children (7 boys), median age 10.8 years (interquartile range (IQR), 9–14), and 10 healthy control children, median age 12 years (IQR, 10.5–12.7), were recruited. ENO was measured using a chemiluminescence analyzer, with sputum induction with 3.5% saline. PCD children underwent ambulatory cough monitoring. Sputum neutrophils were higher in PCD (median, 70.3%; IQR, 55.3–78%) compared to controls (median, 27%; IQR, 24.5–33%; P = 0.004); cough frequency was higher (median episodes, 19; IQR, 11–22.5) compared to healthy children (median episodes, 6.7; IQR, 4.1–10.5; P < 0.001). Forced expiratory volume in 1 sec (FEV1 percent predicted) and eNO were lower in PCD (median, 63%; IQR, 57–85%; P < 0.0001); eNO (median, 7.1 ppb (IQR, 4.8–19.1 ppb) vs. 12.4 ppb (IQR, 10.3–17.3 ppb), P = 0.043). Parental scoring of day and night cough correlated with recorded cough (r = 0.930, P < 0.0001, daytime; r = 0.711 for nighttime, P = 0.002). Visual analogue score and cough episodes also correlated positively (r = 0.906; P < 0.0001). There was a positive correlation between cough frequency and sputum neutrophil count in PCD (Spearman's r = 0.693, P < 0.002), but not percent FEV1 or eNO. Stable PCD children have increased cough frequency and neutrophilic airway inflammation. In conclusion, cough frequency correlated with sputum neutrophils but not with FEV1 or eNO. Pediatr Pulmonol © 2005 Wiley‐Liss, Inc.
Room temperature photoluminescence of the Li2ZnTi3O8 spinel: Experimental and theoretical study
Authors: Câmara M. S. C. , Gurgel M. F. C. , Lazaro S. R. , Boschi T. M. , Pizani P. S. , Leite E. R. , Beltran A. , Longo E.
Published: April 2005

This article describes the characterization of intense photoluminescence observed at room temperature of the Li2ZnTi3O8 spinel phase, obtained by the polymeric precursor method. The evolution of visible photoluminescence is demonstrated by measurement of the photoluminescence signal as a function of the annealing treatment time. The evolution indicates that PL can be attributed to the presence of an inorganic disordered phase. In addition, increased annealing treatment times cause not only a decrease in the total residual content of organic material in the samples, but also an intensified photoluminescence. We discuss the nature of visible photoluminescence at room temperature of the Li2ZnTi3O8 spinel phase in the light of results of both recent experimental and quantum mechanical theoretical studies. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
New adapted Gaussian basis sets for the relativistic closed shell atoms from helium to barium generated with the generator coordinate Dirac‐Fock method
Authors: De Macedo L. G. M. , Morgon N. H. , Haiduke R. L. A. , Barbosa R. C. , Da Silva A. B. F.
Published: April 2005

The generator coordinate Dirac‐Fock (GCDF) method and the downhill simplex algorithm were applied to generate new adapted Gaussian basis sets for relativistic closed shell atoms from He (Z = 2) to Ba (Z = 56). These new basis sets have a size reduction of about 30% when compared to previous GCDF adapted basis sets, and are as compact as some corresponding nonrelativistic Gaussian basis sets. The truncation error is in a millihartree order of magnitude and the optimization scheme adopted here allowed the l‐ and l+ relativistic symmetries to be different. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
A systematic nomenclature of chromosomal elements for hemiascomycete yeasts
Authors: Durrens Pascal , Sherman David James
Published: April 2005

We present a compact, stable, unambiguous and extensible nomenclature for unique chromosomal elements from genomic DNA, developed to meet the increasing need created by the increasing number of yeast sequencing projects. Our proposal, adopted for use in the Génolevures project, is specifically designed to facilitate basic tasks in comparative genomics. Copyright © 2005 John Wiley & Sons, Ltd.
Records of the δ13C of atmospheric CH4 over the last 2 centuries as recorded in Antarctic snow and ice
Authors: Sowers Todd , Bernard Sophie , Aballain Olivier , Chappellaz Jérôme , Barnola Jean‐Marc , Marik Thomas
Published: April 2005

Methane is one of the important greenhouse gases accumulating in the atmosphere today. The increased loading over the past 2 centuries is thought to be the result of increased anthropogenic emissions. Here we present records of the δ13C of CH4 in firn air from the South Pole and in trapped bubbles in a short ice core from Siple Dome, Antarctica, that help constrain historical emissions of various sources throughout the last 2 centuries. Using two firn air samplings in 1995 and 2001 we calculate that δ13CH4 has increased by an average of 0.06 ± 0.02‰/yr over the 6 years between samplings. Our ice core results suggest the δ13C of atmospheric CH4 has increased by 1.8 ± 0.2‰ between 1820 A.D. and 2001 AD. The δ13CH4 changes in both data sets are the result of an increase in the relative proportion of CH4 sources with elevated 13C/12C isotope ratios. One explanation for observed trends involves a 16 Tg/yr increase in CH4 emissions associated with biomass burning over the past 2 centuries.
Parallel simulations of aerosol influence on clouds using cloud‐resolving and single‐column models
Authors: Ovtchinnikov Mikhail , Ghan Steven J.
Published: April 2005

The influence of the cloud condensation nucleus (CCN) concentration on the properties of low‐level clouds under the conditions observed over the north central Oklahoma on 24–25 September 1997 is examined in a series of 18‐hour simulations using a single‐column model (SCM) and a cloud‐resolving model (CM). Both models predict higher droplet concentration, smaller droplet size, and larger liquid water path in a “polluted” case (CCN concentration = 1000 cm−3) than in a clean case (CCN concentration = 250 cm−3), suggesting that the first and the second indirect effects act in unison under the considered conditions. A comparison of the simulations using the SCM and CM with the same two‐moment bulk microphysics parameterization highlights the dominant effect of the dynamical framework on both microphysical and macrophysical properties of modeled cloud. This effect is much stronger than the variations in each of the models resulting from changing CCN concentrations. However, the relative liquid water path sensitivity to CCN concentration is similar between the SCM and CM simulations. The CM simulations with the size‐resolved and the two‐moment bulk microphysical parameterization yield nearly identical structure of boundary layer. Even though these simulations are in much closer agreement with each other than they are with the SCM results, the variance from the microphysics treatment is still comparable to the effect of quadrupling CCN concentration.
Studying ocean acidification with conservative, stable numerical schemes for nonequilibrium air‐ocean exchange and ocean equilibrium chemistry
Authors: Jacobson Mark Z.
Published: April 2005

A noniterative, implicit, mass‐conserving, unconditionally stable, positive‐definite numerical scheme that solves nonequilibrium air‐ocean transfer equations for any atmospheric constituent and time step is derived. The method, referred to as the Ocean Predictor of Dissolution (OPD) scheme, is coupled with EQUISOLV O, a new ocean chemical equilibrium module based on the EQUISOLV II atmospheric aerosol solver. EQUISOLV O converges iteratively, but is unique because it is positive‐definite and mass and charge conserving, regardless of the number of iterations taken or equations solved. Two advancements of EQUISOLV O were the development of a new method to initialize charge and a noniterative solution to the water dissociation equation. Here OPD‐EQUISOLV O is used to calculate air and ocean composition and ocean pH among dozens of species in the Na‐Cl‐Mg‐Ca‐K‐H‐O‐Li‐Sr‐C‐S‐N‐Br‐F‐B‐Si‐P system. The modules are first used in a one‐dimensional ocean/two‐compartment atmospheric model driven by emission to examine the historic change in atmospheric CO2 and ocean composition from 1751 to 2004 and the possible future change in CO2 and ocean composition from 2004 to 2104. CO2 estimates from the historic simulation compare well with the measured CO2 record. Whereas surface ocean pH is estimated to have dropped from near 8.25 to near 8.14 between 1751 and 2004, it is forecasted to decrease to near 7.85 in 2100 under the SRES A1B emission scenario, for a factor of 2.5 increase in H+ in 2100 relative to 1751. This “ocean acidification” is calculated to cause a nontrivial transfer of ammonia from the atmosphere to the ocean and a smaller transfer of hydrochloric acid, nitric acid, and sulfurous acids from the ocean to the atmosphere. The existence and direction of these feedbacks are almost certain, suggesting that CO2 buildup may have an additional impact on ecosystems. Computer time of the module in the GATOR‐GCMOM global model with a 10‐layer‐ocean was less than two hours per simulation year on a modern single processor.
Time- and frequency-resolved fluorescence spectra of nonadiabatic dissipative systems: What photons can tell us
Authors: Egorova Dassia , Gelin Maxim F. , Domcke Wolfgang
Published: April 2005

The monitoring of the excited-state dynamics by time- and frequency-resolved spontaneous emission spectroscopy has been studied in detail for a model exhibiting an excited-state curve crossing. The model represents characteristic aspects of the photoinduced ultrafast dynamics in large molecules in the gas or condensed phases and accounts for strong nonadiabatic and electron-vibrational coupling effects, as well as for vibrational relaxation and optical dephasing. A comprehensive overview of the dependence of spontaneous emission spectra on the characteristics of the excitation and detection processes (such as carrier frequencies, pump/gate pulse durations, as well as optical dephasing) is presented. A systematic comparison of ideal spectra, which provide simultaneously perfect time and frequency resolution and thus contain maximal information on the system dynamics, with actually measurable time- and frequency-gated spectra has been carried out. The calculations of real time- and frequency-gated spectra demonstrate that complementary information on the excited-state dynamics can be extracted when the duration of the gate pulse is varied.
Memory effects in polymer stabilized ferroelectric liquid crystals, and their dependence on the morphology of the constituent molecules
Authors: Lee Ji-Hoon , Lim Tong-Kun , Kwon Young-Wan , Jin Jung-Il
Published: April 2005

The origin of distinct memory states (multistable, bistable, monostable) was verified in thiol-ene polymer stabilized ferroelectric liquid crystal system. The stabilization is obtained by the polymerized ene in the interlayer space. The multistability and the resolution of memory states has strong correlation with the dichroic ratio of thiol. As the thiol lengthens, thiols are more intersticed between ferroelectric liquid crystal molecules in the layer and the multistability and the resolution were also enhanced, consequently. In addition, it was found that the binding of thiol to the ene through polymerization was essential for the realization of multistable memory states. The cone mode viscosity was decreased as the thiol lengthens, and this also seems to promote multistability and resolution of memory.
Microstructural and chemical studies of interfaces between Cu(In,Ga)Se2 and In2S3 layers
Authors: Abou-Ras D. , Rudmann D. , Kostorz G. , Spiering S. , Powalla M. , Tiwari A. N.
Published: April 2005

Microstructural and chemical properties of the interfaces between Cu(In,Ga)Se2 (CIGS) and In2S3 layers in dependence on the In2S3 deposition temperature and Na concentration were investigated. The In2S3 layers were deposited by atomic layer deposition on CIGS layers at substrate temperatures ranging from 140°C to 240°C. Interfaces were investigated by means of scanning electron microscopy, bright-field and high-resolution transmission electron microscopy, electron diffraction, and energy-dispersive x-ray spectrometry. An orientation relationship between CIGS {112) and In2S3 {103) planes was found for the sample deposited at 210°C, whereas no orientation relationship was detected for the 240°C sample. Cu diffusion from CIGS into In2S3 was detected, as well as Cu depletion and In enrichment on the CIGS side of the interface. All three effects are enhanced with increasing deposition temperature. These results indicate the formation of a buried junction in the CIGS layer. In addition, a Na-free solar cell was investigated. The results show that In2S3 grain sizes are smaller than in solar cells containing Na. Also, enhanced Cu and Ga diffusion from the CIGS absorber into the In2S3 buffer as well as enhanced Cu depletion and In enrichment on the CIGS side of the interface were detected. This may indicate that both Na and Cu occupy vacancies and In sites in the In2S3 tetragonal spinel structure.
High-level ab initio calculations for the four low-lying families of minima of(H2O)20. II. Spectroscopic signatures of the dodecahedron, fused cubes, face-sharing pentagonal prisms, and edge-sharing pentagonal prisms hydrogen bonding networks
Authors: Fanourgakis George S. , Aprà Edoardo , de Jong Wibe A. , Xantheas Sotiris S.
Published: April 2005

We report the first harmonic vibrational spectra for each of the lowest lying isomers within the four major families of minima of (H2O)20, namely, the dodecahedron, fused cubes, face-sharing pentagonal prisms, and edge-sharing pentagonal prisms. These were obtained at the second-order Møller–Plesset perturbation level of theory (MP2) with the augmented correlation consistent basis set of double zeta quality (aug-cc-pVDZ) at the corresponding minimum energy geometries. The computed infrared (IR) spectra are the first ones obtained from first principles for these clusters. They were found to contain spectral features, which can be directly mapped onto the distinctive spectroscopic signatures of their constituent tetramer, pentamer, and octamer fragments. The dodecahedron spectra show the richest structure in the OH stretching region and are associated with the most redshifted OH vibrations with respect to the monomer. The lowest lying edge-sharing pentagonal prism isomer displays intense IR active vibrations that are redshifted by ∼600cm−1 with respect to the water monomer. Furthermore the most redshifted, IR-active OH stretching vibrations for all four networks correspond to hydrogen bonded OH groups, which exhibit the following two common characteristics: (i) they belong to fragments which have a “free” OH stretch and (ii) they act as donors to a neighboring water molecule along a “dimerlike” (strong) hydrogen bond. The zero-point energy corrected MP2/CBS (complete basis set) limit binding energies D0 for the four isomers are −163.1 kcal/mol (edge-sharing pentagonal prism), −160.1 kcal/mol (face-sharing pentagonal prism), −157.5 kcal/mol (fused cubes), and −148.1 kcal/mol (dodecahedron).
Magnetoresistance and Hall-effect measurements of Ni thin films
Authors: Boye Shawn A. , Lazor Peter , Ahuja Rajeev
Published: April 2005

High-field magnetotransport experiments have been conducted in the transverse mode on Ni0.985O0.015 thin films between 280 and 380K in applied magnetic fields up to 10T. The magnetic resistivity above the technical saturation of the magnetization, −0.0161(1)μΩcmT−1 at 298K, is found to be negative and linear up to the maximum applied field and the zero-temperature magnon mass determined, 535(14)meVÅ2 [B. Raquet, M. Viret, J. M. Broto, E. Sondergard, O. Cespedes and R. Mamy, J. Appl. Phys. 91, 8129 (2002).]. The application of high magnetic fields is found to reduce the electron-magnon scattering processes due to spin-wave damping. The extraordinary Hall coefficient, RE=−30.5(1)×10−10m3C−1 at 298K, is a smooth function of the temperature and side-jump scattering is considered dominant. Numerical calculations of the d-band density of states conducted using a supercell of 64 atoms reveal that replacing one nickel atom with oxygen results in a 60% decrease in the density of states at the Fermi level. Calculations corresponding to the sample chemistry give an induced magnetic moment on oxygen, 0.208μB, and a slightly higher magnetic moment on nickel, 0.683μB, than calculated for pure nickel, 0.668μB, thereby, accounting for the increased magnon mass.
Ground-state properties and static dipole polarizabilities of the alkali dimers from K2n to Fr2n(n=,+1) from scalar relativistic pseudopotential coupled cluster and density functional studies
Authors: Lim Ivan S. , Schwerdtfeger Peter , Söhnel Tilo , Stoll Hermann
Published: April 2005

The newly adjusted energy-consistent nine-valence-electron pseudopotentials for K to Fr are used to calculate spectroscopic properties for the neutral and positively charged alkali dimers using coupled cluster and density functional theory. For the neutral dimers the static dipole polarizability was calculated. The coupled cluster results are all in excellent agreement with experimental values. The density functionals used can give quite different spectroscopic properties especially for the dipole polarizability, with the Perdew–Wang PW91 functional performing best.
Protonated water clusters described by an empirical valence bond potential
Authors: James Tim , Wales David J.
Published: April 2005

The properties of low-lying stationary points on the potential energy surfaces of singly protonated water clusters (H2O)nH+, are investigated using an empirical valence bond potential. Candidate global minima are reported for n=2–4, 8, and 20–22. For n=8, the variation in the energies and structures of low-lying minima with the number of valence bond states included in the model is studied. For n=4 and 8, disconnectivity graphs are also reported and are compared to results for the equivalent neutral water clusters as described by the rigid TIP3P potential. For the larger clusters, n=20–22, the structural properties of the low energy minima are compared with recently published spectroscopic data on these systems. The observed differences between the n=20 and n=21 systems are qualitatively reproduced by the model potential, but the similarities between the n=21 and n=22 systems are not.
Electrical profiles of ultrashallow p+ layers formed in Si by low-energy BF2+ ion implantation
Authors: Tamaki Y. , Ozaki D. , Inada T.
Published: April 2005

Carrier-concentration and mobility profiles formed in Si by BF2 implantation and by subsequent rapid thermal annealing (RTA) have been examined by differential Hall-effect measurements. B-concentration profiles are measured before and after RTA by a secondary-ion-mass spectroscopic technique. It is shown that a significant amount of B atoms, over 40% of an effective implant dose, is lost during RTA if the substrate is dipped in a dilute HF solution prior to annealing. The loss of B atoms gives rise to the increase in sheet resistivity of the formed p-type layers. It is revealed that an approximately 1.3–1.5-nm-thick, native oxide layer acts as an encapsulant and depresses the loss of implanted B atoms from the substrate during RTA at/above 950 °C, resulting in the formation of an electrical profile with a long tail. The redistribution of B atoms during RTA is suppressed in the sample from which the native oxide has been stripped. Also, an approximately 25-nm-thick, p+ layer with a maximum carrier concentration of 1×1020∕cm3 is formed by 3-keV BF2 implantation and subsequent RTA at 1000 °C. Experimental data indicate that the HF dipping effect is negligibly small if BF2 implantation is carried out above 40 keV.
Transport in superconducting niobium films for radio frequency applications
Authors: Halbritter J.
Published: April 2005

Nb films have been used for many years in superconducting electronics and in rf cavity applications. Recent interest in high rf power TM cavities raises new issues. It is well known that in unprotected Nb films oxidation deteriorates external surfaces strongly and proceeds rapidly along growth island boundaries, resulting in networks of strong and weak links. In superconducting electronics high dc transport current densities Jc are needed. The surface resistance increases exponentially with temperature T and with frequency like ω2, R(T⩽Tc∕2,ω<Δ∕30ℏ)∝ω2exp(−Δ∕kT), with the gap frequency 2Δ∕h=0.7THz, and this is the regime exploited for rf application. But whereas in dc the best current path defines Jc, in rf even the weakest links are sampled, which yield exceptionally strong increases of Rhys∝ω(B∕Jc)n (n=1,2) at rather low fields. This makes the homogeneity of Nb films and localized heating critical issues that must be addressed for rf applications. In this paper we discuss the effects of oxidation at external surfaces or along growth boundaries, especially the consequences of weak/strong link networks on Jc(T,B) and on R(T,B,ω) at low and high rf power, as well as heat transfer, and other factors and mechanisms that affect cavity performances.