bluuebunny/crossref_metadata_2025_split huggingface dataset:
NIR spectroscopic study of the complexation of neptunium(V) with humic acids: influence of phenolic OH groups on the complex formation
Authors: Sachs S. , Bernhard G. 
Published: April 2005

SummaryThe influence of phenolic OH groups on the Np(V) complexation by humic acids was studied at pH 7 and pH 8 under nitrogen atmosphere applying chemically modified humic acids with blocked phenolic OH groups in comparison to their corresponding unmodified humic acids. The studies were performed by near-infrared (NIR) absorption spectroscopy using the metal ion charge neutralization model for evaluation of the experimental data. For all humic acids under investigation comparable complexation constants were determined. However, the studied modified humic acids Aldrich and M42 show significantly lower loading capacities for NpO2+ions (e.g., pH 7: 7.2%±1.1% and 5.3%±1.0%, respectively) than the corresponding unmodified humic acids (e.g., pH 7: 10.0%±1.5 and 11.2%±1.1, respectively). This result points to a lower amount of maximal available humic acid ligand sites after blocking of phenolic OH groups. From that, it can be concluded that humic acid phenolic OH groups contribute to the interaction between humic acid and Np(V) under the studied conditions. The comparison of the loading capacities obtained for unmodified and modified Aldrich humic acid at pH 7 and pH 8 shows that the impact of phenolic OH groups on the Np(V) complexation by humic acids is increased with increasing pH value.
Development of quantitative analytical methods for the control of actinides in a pyrochemical partitioning process
Authors: Abousahl Said , van Belle P. , Eberle H. , Ottmar H. , Lynch B. , Vallet P. , Mayer K. , Ougier M. 
Published: April 2005

Summary
Advanced nuclear fuel cycles are being developed in order to reduce the long-term radiotoxicity of highly radioactive waste. Pyrochemical partitioning techniques appear particularly attractive for advanced fuel cycles in which the minor actinides are recycled. The electrochemical processes of practical importance are the electrorefining process and the liquid–liquid extraction of transuranic (TRU) elements from fission products using either non-miscible molten metal or molten salt–metal phases. Analytical methods for the accurate assay of actinide elements in these matrices needed to be developed. A quantitative assay is required in order to establish a material balance for process development and – at a later stage – for accountancy and control purposes. To this end radiometric techniques such as energy-dispersive X-ray fluorescence analysis (XRF), neutron coincidence counting (NCC) and high-resolution gamma spectrometry (HRGS) were extensively employed for the quantitative determination of actinides (U, Np, Pu, Am, Cm) in process samples. Comparative analyses were performed using inductively coupled plasma mass spectrometry (ICP-MS). The respective samples were available in small quantities (≅100 mg) either in the form of eutectic salt or in metallic form with Cd, Zr or Bi as major metallic matrix constituents.
Selection Theory for Marker-Assisted Backcrossing
Authors: Frisch Matthias , Melchinger Albrecht E 
Published: April 2005

Abstract
Marker-assisted backcrossing is routinely applied in breeding programs for gene introgression. While selection theory is the most important tool for the design of breeding programs for improvement of quantitative characters, no general selection theory is available for marker-assisted backcrossing. In this treatise, we develop a theory for marker-assisted selection for the proportion of the genome originating from the recurrent parent in a backcross program, carried out after preselection for the target gene(s). Our objectives were to (i) predict response to selection and (ii) give criteria for selecting the most promising backcross individuals for further backcrossing or selfing. Prediction of response to selection is based on the marker linkage map and the marker genotype of the parent(s) of the backcross population. In comparison to standard normal distribution selection theory, the main advantage of our approach is that it considers the reduction of the variance in the donor genome proportion due to selection. The developed selection criteria take into account the marker genotype of the candidates and consider whether these will be used for selfing or backcrossing. Prediction of response to selection is illustrated for model genomes of maize and sugar beet. Selection of promising individuals is illustrated with experimental data from sugar beet. The presented approach can assist geneticists and breeders in the efficient design of gene introgression programs.
A General Framework for Statistical Linkage Analysis in Multivalent Tetraploids
Authors: Wu Rongling , Ma Chang-Xing 
Published: April 2005

Abstract
In multivalent polyploids, simultaneous pairings among homologous chromosomes at meiosis result in a unique cytological phenomenon—double reduction. Double reduction casts an impact on chromosome evolution in higher plants, but because of its confounded effect on the pattern of gene cosegregation, it complicates linkage analysis and map construction with polymorphic molecular markers. In this article, we have proposed a general statistical model for simultaneously estimating the frequencies of double reduction, the recombination fraction, and optimal parental linkage phases between any types of markers, both fully and partially informative, or dominant and codominant, for a tetraploid species that undergoes only multivalent pairing. This model provides an in-depth extension of our earlier linkage model that was built upon Fisher's classifications for different gamete formation modes during the polysomic inheritance of a multivalent polyploid. By implementing a two-stage hierarchical EM algorithm, we derived a closed-form solution for estimating the frequencies of double reduction through the estimation of gamete mode frequencies and the recombination fraction. We performed different settings of simulation studies to demonstrate the statistical properties of our model for estimating and testing double reduction and the linkage in multivalent tetraploids. As shown by a comparative analysis, our model provides a general framework that covers existing statistical approaches for linkage mapping in polyploids that are predominantly multivalent. The model will have great implications for understanding the genome structure and organization of polyploid species.
Using Drosophila to Decipher How Mutations Associated With Human Branchio-Oto-Renal Syndrome and Optical Defects Compromise the Protein Tyrosine Phosphatase and Transcriptional Functions of Eyes Absent
Authors: Mutsuddi Mousumi , Chaffee Benjamin , Cassidy Justin , Silver Serena J , Tootle Tina L , Rebay Ilaria 
Published: April 2005

Abstract
Eyes absent (EYA) proteins are defined by a conserved C-terminal EYA domain (ED) that both contributes to its function as a transcriptional coactivator by mediating protein-protein interactions and possesses intrinsic protein tyrosine phosphatase activity. Mutations in human EYA1 result in an autosomal dominant disorder called branchio-oto-renal (BOR) syndrome as well as congenital cataracts and ocular defects (OD). Both BOR- and OD-associated missense mutations alter residues in the conserved ED as do three missense mutations identified from Drosophila eya alleles. To investigate the molecular mechanisms whereby these mutations disrupt EYA function, we tested their activity in a series of assays that measured in vivo function, phosphatase activity, transcriptional capability, and protein-protein interactions. We find that the OD-associated mutations retain significant in vivo activity whereas those derived from BOR patients show a striking decrease or loss of in vivo functionality. Protein-protein interactions, either with its partner transcription factor Sine oculis or with EYA itself, were not significantly compromised. Finally, the results of the biochemical assays suggest that both loss of protein tyrosine phosphatase activity and reduced transcriptional capability contribute to the impaired EYA function associated with BOR/OD syndrome, thus shedding new light into the molecular mechanisms underlying this disease.
Dynein Promotes Achiasmate Segregation in Schizosaccharomyces pombe
Authors: Davis Luther , Smith Gerald R 
Published: April 2005

Abstract
Most organisms use crossovers (chiasmata) to maintain physical connections between homologous chromosomes that ensure their proper segregation at the first meiotic division. The fission yeast Schizosaccharomyces pombe has a residual ability to segregate homologous chromosomes in the absence of meiotic recombination (achiasmate segregation). Using cytologically tagged chromosomes, we established a role for the microtubule motor dynein in meiotic chromosome segregation. Dhc1, the motor subunit of dynein, is required for chromosome segregation in both the presence and the absence of recombination. Dlc1, a member of the Tctex-1 dynein light-chain family, preferentially affects the segregation of achiasmate chromosomes. Dlc1 is the first identified protein, outside of Drosophila, that preferentially affects achiasmate chromosome segregation. We discuss possible roles of the dynein motor in this process.
Sensitivity to Phosphonoacetic Acid
Authors: Li Lei , Murphy Kelly M , Kanevets Uliana , Reha-Krantz Linda J 
Published: April 2005

Abstract
A mutant allele (pol3-L612M) of the DNA polymerase δ gene in Saccharomyces cerevisiae that confers sensitivity to the antiviral drug phosphonoacetic acid (PAA) was constructed. We report that PAA-sensitivity tagging DNA polymerases is a useful method for selectively and reversibly inhibiting one type of DNA polymerase. Our initial studies reveal that replication by the L612M-DNA pol δ requires Rad27 flap endonuclease activity since the pol3-L612M strain is not viable in the absence of RAD27 function. The L612M-DNA pol δ also strongly depends on mismatch repair (MMR). Reduced viability is observed in the absence of any of the core MMR proteins—Msh2, Mlh1, or Pms1—and severe sensitivity to PAA is observed in the absence of the core proteins Msh6 or Exo1, but not Msh3. We propose that pol3-L612M cells need the Rad27 flap endonuclease and MMR complexes composed of Msh2/Msh6, Mlh1/Pms1, and Exo1 for correct processing of Okazaki fragments.
On the Mutation Rate of Herpes Simplex Virus Type 1
Authors: Drake John W , Hwang Charles B C 
Published: April 2005

Abstract
All seven DNA-based microbes for which carefully established mutation rates and mutational spectra were previously available displayed a genomic mutation rate in the neighborhood of 0.003 per chromosome replication. The pathogenic mammalian DNA virus herpes simplex type 1 has an estimated genomic mutation rate compatible with that value.
Spontaneous Mutations in the Ammonium Transport Gene AMT4 of Chlamydomonas reinhardtii
Authors: Kim Kwang-Seo , Feild Eithne , King Natalie , Yaoi Takuro , Kustu Sydney , Inwood William 
Published: April 2005

Abstract
Evidence in several microorganisms indicates that Amt proteins are gas channels for NH3 and CH3NH2, and this has been confirmed structurally. Chlamydomonas reinhardtii has at least four AMT genes, the most reported for a microorganism. Under nitrogen-limiting conditions all AMT genes are transcribed and Chlamydomonas is sensitive to methylammonium toxicity. All 16 spontaneous methylammonium-resistant mutants that we analyzed had defects in accumulation of [14C]methylammonium. Genetic crosses indicated that 12 had lesions in a single locus, whereas two each had lesions in other loci. Lesions in different loci were correlated with different degrees of defect in [14C]methylammonium uptake. One mutant in the largest class had an insert in the AMT4 gene, and the insert cosegregated with methylammonium resistance in genetic crosses. The other 11 strains in this class also had amt4 lesions, which we characterized at the molecular level. Properties of the amt4 mutants were clearly different from those of rh1 RNAi lines. They indicated that the physiological substrates for Amt and Rh proteins, the only two members of their protein superfamily, are NH3 and CO2, respectively.
Treatment of Childhood Constipation by Primary Care Physicians: Efficacy and Predictors of Outcome
Authors: Borowitz Stephen M. , Cox Daniel J. , Kovatchev Boris , Ritterband Lee M. , Sheen Jennifer , Sutphen James 
Published: April 2005

Objective. Childhood constipation accounts for 3% of visits to general pediatric clinics and as many as 30% of visits to pediatric gastroenterologists. The majority of children who experience constipation and whose caregivers seek medical care are seen by primary care physicians such as pediatricians or family physicians. Little is known about how primary care physicians treat childhood constipation or the success of their treatments. With this study, we prospectively examined which treatments primary care physicians prescribe to children who present for the first time with constipation and how effective those treatments are.Methods. A total of 119 children who were between 2 and 7 years of age (mean: 44.1 ± 13.6 months) and presented to 26 different primary care physicians (15 pediatricians and 11 family physicians) for the treatment of constipation for the first time participated in this study. Parents completed daily diaries of their child's bowel habits for 2 weeks before starting treatment recommended by their primary care physician and again 2 months after treatment. The prescribed treatment was identified by reviewing office records of the treating physicians.Results. After 2 months of treatment, 44 (37%) of 119 children remained constipated. In the majority (87%) of cases, physicians prescribed some form of laxative or stool softener. The most commonly prescribed laxatives were magnesium hydroxide (77%), senna syrup (23%), mineral oil (8%), and lactulose (8%). In nearly all cases, a specific fixed dose of laxative was recommended; in only 5% of cases were parents instructed clearly to adjust the dose of laxative up or down to get the desired effect. In approximately half of the cases, physicians recommended some sort of dietary intervention. Some form of behavioral intervention was mentioned in the office records of approximately one third of cases; however, in most cases, little detail was provided. In 45% of cases, physicians prescribed disimpaction using oral cathartics, enemas, or suppositories followed by daily laxatives. In 35% of cases, physicians prescribed daily laxatives without any disimpaction procedure. In the remainder, physicians prescribed only dietary changes (5%), the use of intermittent laxatives (9%), or no therapy (7%). Treatment success corresponded to how aggressively the child was treated. Specifically, children who underwent some form of colonic evacuation followed by daily laxative therapy were more likely to have responded to treatment than were those who were treated less aggressively.Conclusion. Primary care physicians tend to undertreat childhood constipation. After 2 months of treatment, nearly 40% of constipated children remain symptomatic.
Primary Hyperparathyroidism in Pediatric Patients
Authors: Kollars Josh , Zarroug Abdalla E. , van Heerden Jon , Lteif Aida , Stavlo Penny , Suarez Luis , Moir Christopher , Ishitani Michael , Rodeberg David 
Published: April 2005

Objective. Primary hyperparathyroidism (HPT) is unusual in children. We reviewed our experience with HPT to better characterize these children.
Methods. The retrospective review of patients &lt;19 years old who underwent parathyroid resection for primary HPT from 1970 to 2000 was performed at a single institution..
Results. Fifty-two patients were identified. Median age was 16.8 years (range: 4–18.9) with a female-to-male ratio of 3:2. Eighty-five percent had an elevated parathyroid hormone (PTH) level, and 15% had an inappropriately normal PTH level during hypercalcemia. Serum calcium was elevated in all patients except for 2 with multiple endocrine neoplasma (MEN)-IIA and 1 with familial non-MEN HPT, but both had elevated PTH levels. Alkaline phosphatase levels were significantly higher in children with documented bone involvement. At presentation 41 patients (79%) were symptomatic and end-organ damage (nephrocalcinosis, nephrolithiasis, acute pancreatitis, or bone involvement) occurred in 23 patients (44%). Thirty-four patients (65%) had a single adenoma; hyperplasia was identified in 16 patients (27%), and of these cases, 57% occurred in patients diagnosed with MEN-I. Short-term complications included transient hypocalcemia in 29 patients (56%) and transient vocal cord paralysis in 2 patients (4%). Long-term complications were significant for permanent hypocalcemia in 2 patients (4%) and no recurrent laryngeal nerve injuries. No parathyroid abnormalities were identified during exploration in 4 (8%) children. Long-term follow-up was achieved in 98% of patients for a mean and median of 13 years. Resolution of hypercalcemia was achieved in 94% of cases.
Conclusion. The diagnosis of primary HPT in pediatric patients is frequently delayed, is commonly symptomatic, and has significant morbidity. For children in whom HPT is suspected, evaluation of serum calcium and PTH levels is diagnostic in 100% of children. Parathyroid resection is effective at restoring normal serum calcium, has few complications, and is the treatment of choice for children with primary hyperparathyroidism.
Neonatal Ventilation With Inhaled Nitric Oxide Versus Ventilatory Support Without Inhaled Nitric Oxide for Preterm Infants With Severe Respiratory Failure: The INNOVO Multicentre Randomised Controlled Trial (ISRCTN 17821339)
Authors: Field D. , Elbourne D. , Truesdale A. , Grieve R. , Hardy P. , Fenton A.C. , Subhedar N. , Ahluwalia J. , Halliday H.L. , Stocks J. , Tomlin K. , Normand C. ,   on behalf of the INNOVO Trial Collaborating Group
Published: April 2005

Background. Although inhaled nitric oxide (iNO) may be a promising treatment for newborn infants with severe respiratory failure, the results from 3 previous small trials were inconclusive.
Methods. Infants of &lt;34 weeks' gestation, &lt;28 days old, and with severe respiratory failure requiring ventilatory support were randomized to receive or not receive iNO. The study was not blinded.
Findings. Recruited were 108 infants (55 allocated to receive iNO and 53 not allocated to receive iNO) from 15 neonatal units in the United Kingdom and Republic of Ireland. Fifty-nine percent (64 of 108) died, and 84% of the survivors (37 of 44) had signs of some impairment or disability, 9 (20%) of them classified as severely disabled. There was no evidence of an effect of iNO on the primary outcomes: death or severe disability at 1 year corrected age (relative risk [RR]: 0.99; 95% confidence interval [CI]: 0.76 to 1.29); death or supplemental oxygen on expected date of delivery (RR: 0.84; 95% CI: 0.68 to 1.02); or death or supplemental oxygen at 36 weeks' postmenstrual age (RR: 0.98; 95% CI: 0.87 to 1.12). There was a trend for infants allocated to the iNO group to spend more time on the ventilator (log rank: 3.6), on supplemental oxygen (log rank: 1.4), and in hospital (log rank: 3.5) than those allocated to receive no iNO. This pattern predominantly reflected the infants who died. Mean total costs at 1 year corrected age were significantly higher in the iNO group, partly because of the costs of the gas but mainly because of the difference in initial hospitalization costs.
Interpretation. Evidence of prolongation of intensive care and increased costs of such care, without clear beneficial effects, implies that iNO cannot be recommended for preterm infants with severe hypoxic respiratory failure.
Adult Health and Social Outcomes of Children Who Have Been in Public Care: Population-Based Study
Authors: Viner Russell M. , Taylor Brent 
Published: April 2005

Objective. To examine adult socioeconomic, educational, social, and health outcomes of being in public care in childhood.Methods. The 1970 British birth cohort was followed up at 5 (N = 13135), 10 (14875), 16 (11622), and 30 years (11261). Cases were defined as those ever in statutory or voluntary public care at 5, 10, and 16 years. Self-reported adult outcomes were occupation, educational achievement, general health, psychological morbidity, history of homelessness, school exclusion, and convictions.Results. A total of 343 (3.6%) of 9557 had been in public care &lt;17 years. Nonwhite children were more likely to have been in care (odds ratio [OR]: 3.3; 95% confidence interval [CI]: 2.1–5.4). Controlling for socioeconomic status, men with a history of public care were less likely to attain high social class (OR: 0.6; 95% CI: 0.4–0.9) and more likely to have been homeless (OR: 2.0; 95% CI: 1.1–3.8), have a conviction (OR: 2.3; 95% CI: 1.5–3.4), have psychological morbidity (OR: 1.8; 95% CI: 1.1–3.0), and be in poor general health (OR: 1.6; 95% CI: 1.1–2.6). Similar associations were found in women. Men but not women with a history of care were more likely to be unemployed (OR: 2.6; 95% CI: 1.4–5.0) and less likely to attain a higher degree (OR: 0.4; 95% CI: 0.2–0.7). Nonwhite ethnicity was associated with poorer adult outcomes of being in care.Conclusions. Public care in childhood is associated with adverse adult socioeconomic, educational, legal, and health outcomes in excess of that associated with childhood or adult disadvantage.
Heart Rate Characteristics and Laboratory Tests in Neonatal Sepsis
Authors: Griffin M. Pamela , Lake Douglas E. , Moorman J. Randall 
Published: April 2005

Objective. The evaluation of an infant for suspected sepsis often includes obtaining blood for laboratory tests. The shortcomings of the current practice are that the infant has to appear clinically ill for the diagnosis to be entertained, and the conventional laboratory tests are invasive. We have found that the clinical diagnosis of neonatal sepsis is preceded by abnormal heart rate characteristics (HRC) of reduced variability and transient decelerations, and we have devised a predictive HRC monitoring strategy based on multivariable logistic regression analysis that was developed at one tertiary care NICU and validated at another. We hypothesized that HRC monitoring, which is continuous and noninvasive, might be an adjunct to conventional laboratory tests in the diagnosis of neonatal sepsis. The objective of this study was to test the hypothesis that HRC monitoring adds information to conventional laboratory tests in diagnosing neonatal sepsis.
Methods. We prospectively collected heart rate data in 678 consecutive infants who stayed &gt;7 days in the University of Virginia NICU from July 1999 to July 2003. We prospectively measured HRC and noted 149 episodes of sepsis with positive blood cultures for which data were available in 137. We obtained all laboratory test results for ratio of immature to total neutrophil count, white blood cell count, glucose, platelet count, HCO3, arterial partial pressure of carbon dioxide, and pH. We tested hypotheses using multivariable logistic regression modeling adjusted for repeated measures.
Results. We found that the HRC index, which was available 92% of the time, was highly significantly associated with sepsis (receiver-operating characteristic [ROC] area: 0.73). The ratio of immature to total neutrophil count, white blood cell count (available 4%–8% of the time, usually around the time of suspected sepsis), and blood glucose and pH (available 28% and 38% of the time) were also significantly associated with sepsis (ROC area: 0.75). HRC and laboratory values added independent information to each other, and a predictive model using all significant variables had ROC area of 0.82.
Conclusions. HRC monitoring adds independent information to laboratory tests in the diagnosis of culture-positive neonatal sepsis.