bluuebunny/crossref_metadata_2025_split huggingface dataset:
Participation of DNA Polymerase ζ in Replication of Undamaged DNA in Saccharomyces cerevisiae
Authors: Northam Matthew R , Robinson Heather A , Kochenova Olga V , Shcherbakova Polina V 
Published: October 2009

Abstract
Translesion synthesis DNA polymerases contribute to DNA damage tolerance by mediating replication of damaged templates. Due to the low fidelity of these enzymes, lesion bypass is often mutagenic. We have previously shown that, in Saccharomyces cerevisiae, the contribution of the error-prone DNA polymerase ζ (Polζ) to replication and mutagenesis is greatly enhanced if the normal replisome is defective due to mutations in replication genes. Here we present evidence that this defective-replisome-induced mutagenesis (DRIM) results from the participation of Polζ in the copying of undamaged DNA rather than from mutagenic lesion bypass. First, DRIM is not elevated in strains that have a high level of endogenous DNA lesions due to defects in nucleotide excision repair or base excision repair pathways. Second, DRIM remains unchanged when the level of endogenous oxidative DNA damage is decreased by using anaerobic growth conditions. Third, analysis of the spectrum of mutations occurring during DRIM reveals the characteristic error signature seen during replication of undamaged DNA by Polζ in vitro. These results extend earlier findings in Escherichia coli indicating that Y-family DNA polymerases can contribute to the copying of undamaged DNA. We also show that exposure of wild-type yeast cells to the replication inhibitor hydroxyurea causes a Polζ-dependent increase in mutagenesis. This suggests that DRIM represents a response to replication impediment per se rather than to specific defects in the replisome components.
Genetic Testing of the Hypothesis That Hybrid Male Lethality Results From a Failure in Dosage Compensation
Authors: Barbash Daniel A 
Published: October 2009

Abstract
Several recent studies have suggested that F1 hybrid male lethality in crosses between Drosophila melanogaster and D. simulans is due to a failure in dosage compensation, caused by incompatibilities between D. simulans dosage compensation proteins and the D. melanogaster X chromosome. Contrary to the predictions of this hypothesis, mutations in four essential D. melanogaster dosage compensation genes are shown here to moderately increase rather than decrease hybrid male viability.
DNA Packaging by λ-Like Bacteriophages: Mutations Broadening the Packaging Specificity of Terminase, the λ-Packaging Enzyme
Authors: Feiss Michael , Reynolds Erin , Schrock Morgan , Sippy Jean 
Published: October 2009

Abstract
The DNA-packaging specificities of phages λ and 21 depend on the specific DNA interactions of the small terminase subunits, which have support helix-turn-recognition helix-wing DNA-binding motifs. λ-Terminase with the recognition helix of 21 preferentially packages 21 DNA. This chimeric terminase's ability to package λDNA is reduced ∼20-fold. Phage λ with the chimeric terminase is unable to form plaques, but pseudorevertants are readily obtained. Some pseudorevertants have trans-acting suppressors that change codons of the recognition helix. Some of these codons appear to remove an unfavorable base-pair contact; others appear to create a novel nonspecific DNA contact. Helper-packaging experiments show that these mutant terminases have lost the ability to discriminate between λ and 21 during DNA packaging. Two cis-acting suppressors affect cosB, the small subunit's DNA-binding site. Each changes a cosBλ-specific base pair to a cosB21-specific base pair. These cosB suppressors cause enhanced DNA packaging by 21-specific terminase and reduce packaging by λ-terminase. Both the cognate support helix and turn are required for strong packaging discrimination. The wing does not contribute to cosB specificity. Evolution of packaging specificity is discussed, including a model in which λ- and 21-packaging specificities diverged from a common ancestor phage with broad packaging specificity.
Snf1p Regulates Gcn5p Transcriptional Activity by Antagonizing Spt3p
Authors: Liu Yang , Xu Xinjing , Kuo Min-Hao 
Published: October 2009

Abstract
The budding yeast Gcn5p is a prototypic histone acetyltransferase controlling transcription of diverse genes. Here we show that Gcn5p is itself regulated by Snf1p and Spt3p. Snf1p likely controls Gcn5p via direct interaction. Mutating four residues in the Gcn5p catalytic domain, T203, S204, T211, and Y212 (TSTY), phenocopies snf1 null cells, including Gcn5p hypophosphorylation, hypoacetylation at the HIS3 promoter, and transcriptional defects of the HIS3 gene. However, overexpressing Snf1p suppresses the above phenotypes associated with the phosphodeficient TSTY mutant, suggesting that it is the interaction with Snf1p important for Gcn5p to activate HIS3. A likely mechanism by which Snf1p potentiates Gcn5p function is to antagonize Spt3p, because the HIS3 expression defects caused by snf1 knockout, or by the TSTY gcn5 mutations, can be suppressed by deleting SPT3. In vitro, Spt3p binds Gcn5p, but the interaction is drastically enhanced by the TSTY mutations, indicating that a stabilized Spt3p–Gcn5p interaction may be an underlying cause for the aforementioned HIS3 transcriptional defects. These results suggest that Gcn5p is a target regulated by the competing actions of Snf1p and Spt3p.
The Brains of Very Preterm Newborns in Clinically Stable Condition May Be Hyperoxygenated
Authors: Sorensen Line Caroe , Greisen Gorm 
Published: October 2009

OBJECTIVE: The objective was to compare cerebral oxygenation in preterm newborns with that in healthy term newborns.METHODS: Forty-six preterm newborns with gestational ages of &lt;33 weeks and 25 healthy term newborns were included. The cerebral tissue oxygenation index (c-TOI) was measured by using near-infrared spectroscopy in clinical steady state on the first day of life (median age: 19.2 hours). The mean gestational ages and birth weights in the 2 groups were 29.1 ± 2.6 weeks versus 39.7 ± 1.3 weeks and 1307 ± 437 g versus 3484 ± 346 g, respectively. Three preterm infants needed mechanical ventilation and 11 received inotropic drugs. Later, 3 preterm infants developed intraventricular hemorrhage and 2 infants died. All term infants were healthy newborns recruited in the maternity ward.RESULTS: There was a significant difference in c-TOI (preterm: 78.6% [95% confidence interval: 76.9%–80.3%]; term: 74.7% [95% confidence interval: 72.3%–77.1%]). Preterm newborns had significantly lower fractional tissue oxygen extraction, which suggests lower oxygen extraction in this group. There was no significant correlation between head size and c-TOI. The mean peripheral oxygen saturation was 95% in both groups. The median blood Pco2 for the preterm infants was 6.1 kPa (range: 3.4–7.3 kPa).CONCLUSIONS: Cerebral oxygenation on the first day of life was higher in a group of relatively healthy, very preterm infants in stable condition, compared with healthy term newborns. Slightly elevated blood Pco2 could be the explanation. Prematurity itself does not seem to dispose preterm infants to global cerebral hypoxia.
Asthma Morbidity Among Children Evaluated by Asthma Case Detection
Authors: Gerald Joe K. , Sun Yanhui , Grad Roni , Gerald Lynn B. 
Published: October 2009

OBJECTIVE: Population-based asthma detection is a potential strategy to reduce asthma morbidity in children; however, the burden of respiratory symptoms and health care use among children identified by case detection is not well known.
METHODS: Data come from a school-based asthma case detection validation study of 3539 children. Respiratory symptoms, emergency department (ED) visits, and hospitalizations were assessed by questionnaire for children whose case detection result and physician study diagnosis agreed.
RESULTS: Physician evaluation of 530 case detection results yielded 420 cases of agreement (168 children with previously diagnosed asthma, 39 with undiagnosed asthma, and 213 without asthma). Children with previously diagnosed asthma were more likely to be male (P &lt; .0001). No differences in severity were observed in children with previously and undiagnosed asthma (P = .31). Children with undiagnosed asthma reported less frequent daytime and nighttime symptoms than children with previously diagnosed asthma but more than those without asthma (P &lt; .0001). The proportion of children with at least 1 respiratory-related ED visit in the past year was 32%, 3%, and 3% for those with previously diagnosed, undiagnosed, and no asthma, respectively (P &lt; .0001). The proportion with at least 1 respiratory-related hospitalization was 8%, 0%, and 0%, respectively (P &lt; .0001). There were no differences in nonrespiratory ED visits (P = .93).
CONCLUSIONS: Despite similar physician-rated severity, children with undiagnosed asthma reported significantly less frequent respiratory symptoms and health care use than children with previously diagnosed asthma. These findings suggest that the potential health gains from case detection may be smaller than expected.
Can Association Between Preterm Birth and Autism be Explained by Maternal or Neonatal Morbidity?
Authors: Buchmayer Susanne , Johansson Stefan , Johansson Anna , Hultman Christina M. , Sparén Pär , Cnattingius Sven 
Published: October 2009

OBJECTIVE: We examined whether an association between preterm birth and risk of autistic disorders could be explained by pregnancy complications or neonatal morbidity.METHODS: This Swedish, population-based, case-control study included 1216 case subjects with autistic disorders who were born between 1987 and 2002 and 6080 control subjects who were matched with respect to gender, birth year, and birth hospital. We assessed associations between gestational age and autistic disorders and adjusted for maternal, birth, and neonatal characteristics. Conditional logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs).RESULTS: Compared with infants born at term, the unadjusted ORs for autistic disorders among very and moderately preterm infants were 2.05 [95% CI: 1.26–3.34] and 1.55 [95% CI: 1.22–1.96], respectively. When we controlled for maternal, pregnancy, and birth characteristics, ORs were reduced to 1.48 [95% CI: 0.77–2.84] and 1.33 [95% CI: 0.98–1.81], respectively. When we also controlled for neonatal complications, ORs were 0.98 [95% CI: 0.45–2.16] and 1.25 [95% CI: 0.90–1.75], respectively. Reductions in risks of autistic disorders related to preterm birth were primarily attributable to preeclampsia, small-for-gestational age birth, congenital malformations, low Apgar scores at 5 minutes, and intracranial bleeding, cerebral edema, or seizures in the neonatal period. Neonatal hypoglycemia, respiratory distress, and neonatal jaundice were associated with increased risk of autistic disorders for term but not preterm infants.CONCLUSION: The increased risk of autistic disorders related to preterm birth is mediated primarily by prenatal and neonatal complications that occur more commonly among preterm infants.
Heel-Lancing in Newborns: Behavioral and Spectral Analysis Assessment of Pain Control Methods
Authors: Weissman Amir , Aranovitch Michal , Blazer Shraga , Zimmer Etan Z. 
Published: October 2009

OBJECTIVE: Pain experience can alter clinical outcome, brain development, and subsequent behavior in newborns, primarily in preterm infants. The aims of this study were (1) to evaluate several simple, commonly used methods for pain control in newborns and (2) to evaluate the concordance between behavioral and autonomic cardiac reactivity to pain in term neonates during heel-lancing.
METHODS: A prospective study was conducted of 180 term newborn infants who were undergoing heel-lancing for routine neonatal screening of phenylketonuria and hypothyroidism. Newborns were assigned to 6 groups: (1) control (no pain relief intervention); (2) nonnutritive sucking; (3) holding by mother; (4) oral glucose solution; (5) oral formula feeding; or (6) breastfeeding. Outcome measures included the Neonatal Facial Coding System score; cry duration; and autonomic variables obtained from spectral analysis of heart rate variability before, during, and after heel-lancing.
RESULTS: Infants with no pain control showed the highest pain manifestation compared with newborns to whom pain control was provided. Infants who breastfed or received an oral formula showed the lowest increase in heart rate (21 and 23 beats per minute, respectively, vs 36; P &lt; .01), lowest neonatal facial score (2.3 and 2.9, respectively, vs 7.1; P &lt; .001), lowest cry duration (5 and 13 seconds, respectively, vs 49; P &lt; .001), and lowest decrease in parasympathetic tone (−2 and −2.4, respectively, vs 1.2; P &lt; .02) compared with the other groups.
CONCLUSIONS: Any method of pain control is better than none. Feeding and breastfeeding during heel-lancing were found to be the most effective methods of pain relief.
Secondhand Tobacco Smoke Exposure Among Children and Adolescents: United States, 2003–2006
Authors: Marano Cinzia , Schober Susan E. , Brody Debra J. , Zhang Cindy 
Published: October 2009

OBJECTIVE: The implementation of policies that prohibit tobacco smoking in public places has resulted in a significant reduction in secondhand smoke (SHS) exposure in the US population; however, such policies do not extend to private homes, where children continue to be exposed. Our objective was to assess SHS exposure among US children and adolescents by using serum cotinine measures to compare those who were exposed to SHS in the home and those without home exposure.
METHODS: We analyzed serum cotinine data from the 2003–2006 National Health and Nutrition Examination Survey for 5518 children (3–11 years) and nonsmoking adolescents (12–19 years). We calculated geometric mean serum cotinine levels by sociodemographic and household characteristics according to self-reported home SHS exposure. Multiple regression analysis was conducted to evaluate independent predictors of serum cotinine levels.
RESULTS: Geometric mean serum cotinine levels were 1.05 ng/mL among those with home SHS exposure and 0.05 ng/mL among those without home exposure. Among children who were exposed to SHS at home, serum cotinine levels were inversely associated with age and were similar for non-Hispanic black and non-Hispanic white children. Conversely, among children without SHS exposure at home, serum cotinine levels were higher among non-Hispanic black compared with non-Hispanic white children, and there was no relationship with age. Mexican American children had the lowest level of SHS exposure.
CONCLUSIONS: Serum cotinine levels were an order of magnitude higher among children with reported SHS exposure at home compared with those with no exposure in the home.
Effectiveness of Belt Positioning Booster Seats: An Updated Assessment
Authors: Arbogast Kristy B. , Jermakian Jessica S. , Kallan Michael J. , Durbin Dennis R. 
Published: October 2009

OBJECTIVE: The objective of this study was to provide an updated estimate of the effectiveness of belt-positioning booster (BPB) seats compared with seat belts alone in reducing the risk for injury for children aged 4 to 8 years.
METHODS: Data were collected from a longitudinal study of children who were involved in crashes in 16 states and the District of Columbia from December 1, 1998, to November 30, 2007, with data collected via insurance claims records and a validated telephone survey. The study sample included children who were aged 4 to 8 years, seated in the rear rows of the vehicle, and restrained by either a seat belt or a BPB seat. Multivariable logistic regression was used to determine the odds of injury for those in BPB seats versus those in seat belts. Effects of crash direction and booster seat type were also explored.
RESULTS: Complete interview data were obtained on 7151 children in 6591 crashes representing an estimated 120646 children in 116503 crashes in the study population. The adjusted relative risk for injury to children in BPB seats compared with those in seat belts was 0.55.
CONCLUSIONS: This study reconfirms previous reports that BPB seats reduce the risk for injury in children aged 4 through 8 years. On the basis of these analyses, parents, pediatricians, and health educators should continue to recommend as best practice the use of BPB seats once a child outgrows a harness-based child restraint until he or she is at least 8 years of age.
Settlement Studies in Egypt
Authors: Hanna W. S. 
Published: October 2009

Synopsis Settlement studies have formed an important part of the research carried out at Fouad I University, Cairo. Comparisons between observed and theoretical settlements, based on the results of the consolidation tests, showed that, relatively, the results were quite close; but numerically the theoretical settlements were, in many buildings, 3–4 times the observed values. Studies made seemed to indicate that the disturbance of swelling clays on removal from samplers accounted for an important part of the difference. This led to the development by the Author of a sampler that permitted the testing of the sample without removal from the sampler. Under the clay conditions existing in Egypt the “ring” sampler seems to justify itself: comparisons are made in proof of this point. A few examples are given of buildings on rafts and footings, which raise many foundation problems, including that of a lock resting on swelling clays, and also the subject of subgrade reaction. One case of piled foundations is mentioned, bringing to light the special problem of piled foundations under soil conditions such as exist in Egypt. Les études de tassement du sol ont formé une partie importante des travaux de recherches entrepris à l'Université Fouad Ier au Caire. Les comparaisons entre les tassements observés et ceux théoriques, barées sur les résultats des essais de consolidations, ont montré que les résultats étaient relativement proches; mais en chiffres, les tassements théoriques ont été, dans de nombreuses constructions, de 3 à 4 fois les valeurs observées. Des études faites sur ce point ont semblé indiquer que le dérangement de l'argile foisonnante provoqué par l'éloignement de dedans les échantilloneuses était la cause d'une partie importante de la différence dans les réultats. Ceci a conduit l'Auteur à la mise au point d'une échantilloneuse permettante les essais des échantillons saris avoir à les retirer de 1'échantilloneuse. Si l'on considère les argiles en présence desquelles on se trouve en Egypte, l'échantilloneuse “annulaire” se justifie de luimême: des essais de comparaison sont faits pour venir à l'appui de ce point. Quelques exemples sont donnés constructions sur radiers et sur empattements qui soulèvent de nombreux problèmes de fondation, y compris la construction d'une écluse reposant sur de l'argile foisonnante, et aussi le sujet de réactions de la plate-forme. On mentionne un cas de fondations sur pieux, faisant ressortir le problème particulier des fondations sur pieux dans les conditions de sol existantes en Egypte.
The Measurement of the Surface Bearing-Capacity of Soils in the Study of Earth-Crossing Machinery
Authors: Evans Ivor 
Published: October 2009

Synopsis Methods of measuring the surface bearing-capacity of soils have been studied in relation to the design of tractors. It has been found that the simplest method of measurement for undisturbed alluvial clays is by means of a portable field vane, which is described. Cultivated soils must be subjected to a suitable degree of compaction before being tested. Rearing capacity can be estimated from a cone bearing-test, even for sandy loams having a small clay content. It is shown that, for the sizes of bearing area that are common in vehicle design, the error involved in scaling-up is small, even when the angle of shearing resistance of the soil is high. It has been found that the ratio of shearing resistance, as measured by the vane, to cone bearing-capacity is roughly independent of the angle of shearing resistance. This means that an estimate of bearing capacity can be obtained from the vane even in sandy loams. The theoretical implications of this relationship are discussed. On a étudié des méthodes de mesurer la force portante des terrains en surface en relation avec le hessin des tracteurs. Pour les terrains d'alluvions argileuses intactes, il a été trouvé que la méthode la plus simple était au moyen d’un moulinet portative. dont une description est donnée. Les terrains cultivés doivent être soumis à un tassement approprié avant d'être soumis à des essais. La force portante peut être estimée à la suite d'un essai de support du cône, même pour les'terrains sablonneux n'ayant qu'une faible teneur en argile. I1 est prouvé que. en raison des tailles de surfaces de support utilisées en générals dans le dessin des véhicules, l'érreur provenant de la mise à l'échelle des résultats obtenus est faible, même quand l'angle de résistance au cisaillement du terrain est é1evé. Il a été trouvé que le rapport entre la résistance au cisaillement, telle qu'elle est mesurée par le moulinet, et la capacité de support du cône est approximativement indépendant de l'angle de réstance au cisaillement. Ceci signifie qu'on peut obtenir une estimation de la force portante, à l'aide du moulinet, même en terres grasses sablon-neuses. Les implications théoriques de ce rapport sent soumises à discussion.
Protection of the Ground from Thermal Effects of Industrial Plant
Authors: Ward W. H. , Sewell E. C. 
Published: October 2009

Synopsis Solutions have been obtained for the uniform thickness of insulation necessary to maintain a specified temperature below thermal plant of long-rectangular and circular plan, resting on the surface of the ground or sunk in the ground as a basement. A shape factor enables the solutions to be used for other simple shapes. Solutions are also derived for the heat-flow from the base of the insulated thermal plant. Examples are given. The amount of insulation required to ensure a safe ground temperature under high-temperature plant and under large cold stores is shown to be considerably greater than is used in practice. Numerous failures have occurred through the deleterious action of extreme ground temperatures. High-temperature plant requires protection of the ground by means of a ventilated cavity below a moderate thickness of insulation. A simple method of design is outlined, and the results of a successful application of this principle to a brick-kiln are shown. On a calculé quelle était l'epaisseur uniforme de matériel isolant nécessaire pour maintenir le sol à une certaine température sous des installations industrielles thermiques en forme de cercle ou de rectangle allongé, posées à ras du sol ou situées dans des souterrains. On a prévu un facteur-forme, permettant d'appliquer les calculs à d'autres constructions de formes géométriques simples. On a calculé également la chaleur transmise par la base d'installations thermiques pourvues d'une couche isolante. Ilest démontré que la quantité de matériel isolant nécessaire pour assurer la protection du sol sous des installations à hautes températures ou sous des installations frigorifiques est beaucoup plus grande que celle qu'on utilise couramment en pratique. Plusieures constructions ont été sérieusement endommagées par l'effet de températures extrèmes dans le sol. Les installations industrielles à hautes températures devront étre séparées du sol par une couche de matérial isolant d'épaisseur moyenne et par un espace ventilé. Les calculs s'effectuent suivant une méthode simple et un exemple est donné qui montre des resultats satisfaisants obtenus en appliquant ce principe à la construction d'un four à briques.