bluuebunny/crossref_metadata_2025_split huggingface dataset:
‘Species’ of peptidases
Authors: Barrett Alan J. , Rawlings Neil D. 
Published: November 2007

Abstract
A good system for the naming and classification of peptidases can contribute much to the study of these enzymes. Having already described the building of families and clans in the MEROPS system, we here focus on the lowest level in the hierarchy, in which the huge number of individual peptidase proteins are assigned to a lesser number of what we term ‘species’ of peptidases. Just over 2000 peptidase species are recognised today, but we estimate that 25 000 will one day be known. Each species is built around a peptidase protein that has been adequately characterised. The cluster of peptidase proteins that represent the single species is then assembled primarily by analysis of a sequence ‘tree’ for the family. Each peptidase species is given a systematic identifier and a summary page of data regarding it is assembled. Because the characterisation of new peptidases lags far behind the sequencing, the majority of peptidase proteins are so far known only as amino acid sequences and cannot yet be assigned to species. We suggest that new forms of analysis of the sequences of the unassigned peptidases may give early indications of how they will cluster into the new species of the future.
Isolation and identification of residual chromophores from aged bleached pulp samples
Authors: Rosenau Thomas , Potthast Antje , Kosma Paul , Suess Hans U. , Nimmerfroh Norbert 
Published: November 2007

Abstract
Three bleached and subsequently aged cellulosic pulps have been analysed for their chromophore content according to the chromophore release and identification (CRI) method. Several chromophores have been unambiguously identified, despite their very low content (ppb range). This is the first report on defined chromophoric structures isolated from bleached pulps. It is also the first application of the CRI method to cellulose I substrates, rather than to cellulose II substrates (fibres) and cellulose derivatives as hitherto performed. A common feature of the chromophores is the 2-hydroxy-[1,4]benzoquinone moiety, which is strongly stabilized by resonance or tautomerism. The structure of the chromophores indicates that oxidised carbohydrate structures act as precursor moieties, which condense upon ageing to the chromophore structures identified.
Paper mill sludge as a component of wood adhesive formulation
Authors: Geng Xinglian , Deng James , Zhang Shu Yin 
Published: November 2007

Abstract
Three major types of paper mill sludge, primary sludge (PS), secondary sludge (SS) and de-inking paper sludge (DPS) were characterized and evaluated as adhesive fillers. Plywood panels were made of formulations with phenol formaldehyde (PF) and sludges. Panels with PF/PS and PF/SS formulations had higher dry and wet shear strengths than those made with PF/Cocob® formulation. All wood failure values were comparable. Dry and wet shear strengths of the panels with PF/DPS formulation were comparable to those of the PF/Cocob® panels (with Cocob® as a commercial filler), but the former displayed a much lower wood failure value. Owing to this fact and its high ash content, DPS was not evaluated further as a potential component of adhesive formulations. Compared with SS, PS resulted in higher dry and wet shear strengths and higher wood failure values. However, granular SS was easier to disperse into the resin component than fibrous PS, and the PF/SS formulation was more easily dispensed on aspen veneer sheets than the PF/PS formulation. SS alone displayed adhesive properties with 0.87 MPa of dry shear strength, but PS alone did not exhibit any bond strength. PS and SS were further evaluated for their general thermal behavior and major functional groups using differential scanning calorimetry and Fourier transform infrared spectrometry, respectively.
Time/temperature equivalence in the dry wood creep response
Authors: Sun Nanjian , Frazier Charles E. 
Published: November 2007

Abstract
Rheology of wood molecular and supramolecular organization has mostly been conducted with dynamic methods, and the application of time/temperature equivalence typically requires plasticizers to observe segmental relaxation. Dry wood rheology offers the experimental advantage of easy moisture control, but only weak secondary relaxations are observed with dynamic methods. Static methods allow for the longer relaxation times in glassy polymers, and these relaxations are strongly stimulated by lower less damaging temperatures. This study describes the application of creep mode time/temperature equivalence to dry yellow-poplar (Liriodendron tulipifera) and southern yellow pine (Pinus spp.). It was found that time/temperature equivalence was valid from 10–170°C, but only for specimens that received a prior 30-min thermal treatment (with minor desiccation) in the range of 100–170°C. The two woods exhibited clear differences in the temperature dependence of the dry wood creep relaxation, and in the sensitivity to free volume manipulation. These findings are believed to reflect polymer structural differences in hardwoods and softwoods indicating that creep mode time/temperature studies of dry wood may be useful for the analysis of xylem polymer behavior.
Neural network prediction of bending strength and stiffness in western hemlock (Tsuga heterophylla Raf.)
Authors: Mansfield Shawn D. , Iliadis Lazaros , Avramidis Stavros 
Published: November 2007

Abstract
The stiffness and strength, modulus of elasticity (MOE) and modulus of rupture (MOR), as well as density, moisture content, microfibril angle and diffraction pattern coefficient of variation of azimuthal intensity profile (ICV) was determined for 259 small clear specimens. These samples represent 38 old- and second-growth western hemlock (Tsuga heterophylla) trees harvested from several sites in coastal British Columbia, Canada. The data were analyzed by classic statistical regression techniques to reveal interrelations among the mechanical properties and the inherent wood properties. Simultaneously, the predictive power of artificial neural networks was evaluated with the same data set by employing several optimization techniques. Regression analysis of wood density and the flexural strength properties resulted in R2 of 0.172 and 0.332 for MOE and MOR, respectively. The most efficient network model proved to be far superior demonstrating correlation coefficients with models for MOE ranging between 0.693 and 0.750, and the corresponding MOR models ranging between 0.438 and 0.561 in all testing phases. It is apparent that neural networks have the potential and capacity to self-train and become powerful adaptive systems that can predict the strength and stiffness of wood samples. The neural network analysis also revealed the importance level of each independent variable on both MOE and MOR properties.
Bending properties of particleboard and MDF layers
Authors: Wilczyński Arnold , Kociszewski Marek 
Published: November 2007

Abstract
The modulus of elasticity in bending and the bending strength of the face and core layer of particleboard and medium density fiberboard (MDF) were determined. Three directions of longitudinal axis of test specimens were considered: the direction of the mat forming, the direction perpendicular to it, and the direction perpendicular to the panel plane. The experiments were carried out on specimens that were prepared with strips of layers separated from the panels and glued into laminated assemblies. The bending properties of the core and face layer of the tested panels differed considerably. The core layer properties were on average more than 4 times smaller for particleboard and almost 3 times smaller for MDF. The relative differences between the bending properties were greater than the differences between the densities of the layers. The bending properties of the layers were almost isotropic in the planes of layers and very strongly anisotropic in the planes perpendicular to layers. The modulus of elasticity of the tested panels was calculated for the axis corresponding to the mat forming direction. The calculations were performed on the basis of the moduli of panel layers and based on the layered system theory. The results were compared with the modulus determined directly for entire panels. The relative difference between the compared moduli was found to be very small for both tested panels.
Gold as an X-ray CT scanning contrast agent: Effect on the mechanical properties of wood plastic composites
Authors: Wang Yi , Muszynski Lech , Simonsen John 
Published: November 2007

Abstract
Wood plastic composites (WPCs) are typically composed of wood particles, thermoplastic polymers and small amounts of additives. Further improvement of WPC technology requires a better understanding of their mechanical performance and durability on the micro level. X-ray computed tomography (CT) and advanced imaging techniques can provide visualization and support characterization of the internal structure, deformation and damage accumulation in WPCs under loading and various environmental exposures. However, both wood and thermoplastics are weakly attenuating materials for X-ray and good contrast between these two components is difficult to obtain. In the present study, chemically inert gold nano-particles and micro-particles were investigated as contrast agents to improve X-ray CT scanning contrast between wood and thermoplastics. The effect of adding 1% (by wt.) gold nano- and micro-particles on the tensile properties of wood/high-density polyethylene composites was addressed. Samples with and without surfactant were tested in tension and scanned on a custom desktop X-ray CT system. It was found that the addition of gold particles did not impair the WPC tensile properties. However, some of the tensile properties were significantly affected if the surfactant was included. Gold micro-particles were shown to disperse well without surfactant and significantly improve the X-ray CT scanning contrast between wood and polymer, while gold nano-particles (without surfactant) did not disperse well and do not contribute to contrast improvement.
Improvement of Pinus pinaster Ait elite trees selection by combining near infrared spectroscopy and genetic tools
Authors: da Silva Perez Denilson , Guillemain Audrey , Alazard Pierre , Plomion Christophe , Rozenberg Philippe , Carlos Rodrigues José , Alves Ana , Chantre Guillaume 
Published: November 2007

AbstractThe first and the second generation of improved maritime pine (Pinus pinaster) have produced gains of up to 30% in stem volume, a reduction of final harvesting age by 10 years and a considerable improvement of stem straightness. The third generation will include wood quality traits for different end-uses, including pulp and fibre properties. To facilitate this goal, near infrared spectroscopy (NIRS) was used to estimate chemical composition with regard to lignin, cellulose, hemicelluloses, and extractive content, and lignin quality with regard to 4-hydroxy-phenylpropane/guaiacylpropane ratio. A total of 960 samples were investigated which were collected from a large number of trees (belonging to 80 families obtained by crossing 18 mothers and 20 fathers; there are 12 trees per family). Good calibration data was obtained between NIRS and wet chemistry methods (R2values higher than 0.9 and good precision of prediction). To complete the NIRS work, kraft cookings in small scale, fibre morphology and microdensitometry investigations were also conducted. Genetic calculations indicated that for a 1% rate of selection on mothers and fathers, genetically induced changes are possible with lignin content (−3.8%), cellulose content (+1.3%), pulp yield (+1.8%), fibre length in pulps (+0.17 mm) and wood density (+50 kg m−3).
Healing of Nonhymenal Genital Injuries in Prepubertal and Adolescent Girls: A Descriptive Study
Authors: McCann John , Miyamoto Sheridan , Boyle Cathy , Rogers Kristen 
Published: November 2007

OBJECTIVE. The objective of this study was to identify the healing process and outcome of nonhymenal injuries in prepubertal and pubertal girls.
METHODS. This multicenter, retrospective project used photographs to document the healing process and outcome of nonhymenal genital injuries in 239 prepubertal and pubertal girls whose ages ranged from 4 months to 18 years.
RESULTS. The genital injuries sustained by the 113 prepubertal girls consisted of 21 accidental or noninflicted injuries, 73 injuries secondary to abuse, and 19 injuries of unknown cause. All 126 pubertal girls were sexual assault victims. These nonhymenal genital injuries healed at various rates depending on the type and severity. There was no statistical difference in the rate of healing between the 2 groups. Abrasions disappeared by the third day after injury. Edema was no longer present by the fifth day. Ecchymosis (bruising) resolved within 2 to 18 days depending on the severity. One prepubertal girl still had a labial hematoma at 2 weeks. Submucosal hemorrhages of the vestibule and fossa navicularis resolved between 2 days and 2 weeks. Petechiae and blood blisters proved useful for approximating the age of an injury. Petechiae were gone by 24 hours, whereas blood blisters were detected at 30 days in a prepubertal girl and 24 days in a pubertal girl. The depth of a laceration determined the time required for it to heal. Superficial vestibular lacerations seemed healed in 2 days, whereas deep perineal lacerations required up to 20 days. The appearance of new blood vessel formation was detected only in prepubertal girls, whereas scar tissue formation occurred only after a deep laceration in both groups.
CONCLUSIONS. The majority of these nonhymenal genital injuries healed with little or no evidence of previous trauma. The time required for resolution varied by type, location, and severity.
Ontogeny of Bilirubin-Binding Capacity and the Effect of Clinical Status in Premature Infants Born at Less Than 1300 Grams
Authors: Bender George Jesse , Cashore William James , Oh William 
Published: November 2007

BACKGROUND. Bilirubin is toxic to the brain and enters the brain in unbound form. Serum unconjugated, unbound bilirubin may be a good predictor of bilirubin encephalopathy. Unbound bilirubin levels may depend on the bilirubin-binding capacity of albumin, which has not been described for neonates of &lt;28 weeks’ gestation.
OBJECTIVE. The purpose of this work was to determine the ontogeny of bilirubin-binding capacity and the effect of clinical status in very preterm neonates.
METHODS. A total of 152 neonates (23–31 weeks’ gestational age; 440–1300 g) were enrolled prospectively. At 5 days of age, total serum bilirubin and unbound bilirubin were measured with the unbound bilirubin-A1 analyzer (Arrows Co, Osaka, Japan) and albumin with the Bromocresol-purple method. Scatchard plots were used to estimate bilirubin-binding affinity and capacity. Clinical status for each infant was rated as high, moderate, or low risk by using a modified Score for Neonatal Acute Physiology model. Low risk was considered clinically stable.
RESULTS. Unbound bilirubin has a significant, direct correlation to total bilirubin and is greater in unstable than in stable neonates. For the entire cohort, bilirubin-binding capacity had a direct relationship to gestational age. The bilirubin-binding capacities of infants in the low- and high-risk groups also had a direct relationship to gestational age. Bilirubin-binding capacity was greater in the low-risk group (20.8 ± 4.6 mg/dL; 356 ± 79 μmol/L) than in the moderate- (17.8 ± 3.5 mg/dL; 304 ± 60 μmol/L) or high- (17.3 ± 3.4 mg/dL; 296 ± 58 μmol/L) risk groups. Bilirubin-binding affinity did not differ by clinical risk status or gestational age.
CONCLUSIONS. In very preterm, very low birth weight infants, bilirubin-binding capacity is directly proportional to gestational age. Bilirubin-binding capacity is lower and unbound bilirubin higher in unstable than in stable neonates. These data may be useful in guiding the management of hyperbilirubinemia in very low birth weight infants.
Impact of Computerized Prescriber Order Entry on the Incidence of Adverse Drug Events in Pediatric Inpatients
Authors: Holdsworth Mark T. , Fichtl Richard E. , Raisch Dennis W. , Hewryk Adrianne , Behta Maryam , Mendez-Rico Elena , Wong Cindy L. , Cohen Jennifer , Bostwick Susan , Greenwald Bruce M. 
Published: November 2007

OBJECTIVES. This study was conducted to determine the impact of a computerized physician order entry system with substantial decision support on the incidence and types of adverse drug events in hospitalized children.
METHODS. A prospective methodology was used for the collection of adverse drug events and potential adverse drug events from all patients admitted to the pediatric intensive care and general pediatric units over a 6-month period. Data from a previous adverse drug event study of the same patient care units before computerized physician order entry implementation were used for comparison purposes.
RESULTS. Data for 1197 admissions before the introduction of computerized physician order entry were compared with 1210 admissions collected after computerized physician order entry implementation. After computerized physician order entry implementation, it was observed that the number of preventable adverse drug events (46 vs 26) and potential adverse drug events (94 vs 35) was reduced. Reductions in overall errors, dispensing errors, and drug-choice errors were associated with computerized physician order entry. There were reductions in significant events, as well as those events rated as serious or life threatening, after the implementation of computerized physician order entry. Some types of adverse drug events continued to persist, specifically underdosing of analgesics. There were no differences in length of stay or patient disposition between preventable adverse drug events and potential adverse drug events in either study period.
CONCLUSIONS. This study demonstrated that a computerized physician order entry system with substantive decision support was associated with a reduction in both adverse drug events and potential adverse drug events in the inpatient pediatric population. Additional system refinements will be necessary to affect remaining adverse drug events. Preventable events did not predict excess length of stay and instead may represent a sign, rather than a cause, of more complicated illness.
Violent Television Viewing During Preschool Is Associated With Antisocial Behavior During School Age
Authors: Christakis Dimitri A. , Zimmerman Frederick J. 
Published: November 2007

OBJECTIVE. The effect of violent television programming on preschoolers’ behaviors is poorly understood. The objective of this study was to test the hypothesis that exposure to violent television viewing when children are 2 to 5 years of age would be associated with antisocial behavior at ages 7 to 10.
METHODS. Data were derived from the Panel Study of Income Dynamics. Our primary outcome was being in the 88th percentile of the Behavioral Problem Index antisocial subdomain. Our primary predictor was exposure to violent screen content.
RESULTS. Data were available for 184 boys and 146 girls at both time periods. Adjusting for baseline Behavioral Problem Index scores and age, parental education, maternal depression, and cognitive and emotional support, violent television programming was associated with an increased risk for antisocial behavior for boys but not for girls. Neither educational nor nonviolent programming was associated with increased risk for boys or girls.
CONCLUSIONS. Viewing of violent programming by preschool boys is associated with subsequent aggressive behavior. Modifying the content that is viewed by young children may be warranted.
Size at Birth and Motor Activity During Stress in Children Aged 7 to 9 Years
Authors: Schlotz Wolff , Jones Alexander , Phillips Naomi M.M. , Godfrey Keith M. , Phillips David I.W. 
Published: November 2007

OBJECTIVES. Small size at birth is linked with metabolic and cardiovascular disease. There is increasing evidence that it is also linked with physiologic stress responses and abnormal behavior, in particular, symptoms of hyperactivity. Therefore, we investigated associations between size at birth and motor activity during psychosocial stress.
METHODS. In 123 children aged 7 to 9 years, we examined the relations of birth weight, head circumference, length, and ponderal index at birth with motor activity on exposure to both stress and nonstress situations. Videos were recorded while the children performed a story and a math task in front of an audience (stress) and watched a movie (nonstress); motor activity was defined as lifting or tilting of a foot.
RESULTS. Children who had had a smaller head circumference at birth demonstrated greater motor activity during the stress test. There were marked gender differences in the results. In boys, lower birth weight, head circumference, and ponderal index were associated with greater motor activity during the stress test but not associated with motor activity during the nonstress situation. The findings remained significant when potential confounding variables were controlled for. There were no associations in girls.
CONCLUSIONS. The findings suggest long-term effects of an adverse fetal environment on the behavioral stress response in boys and parallel similar gender-specific effects on different stress response systems in humans and animals. The results could reflect permanent alterations of dopaminergic neurotransmission and have implications for the etiology of clinical hyperactivity.
Shorter Sleep Duration Is Associated With Increased Risk for Being Overweight at Ages 9 to 12 Years
Authors: Lumeng Julie C. , Somashekar Deepak , Appugliese Danielle , Kaciroti Niko , Corwyn Robert F. , Bradley Robert H. 
Published: November 2007

OBJECTIVE. The potential association between short sleep duration or sleep problems and childhood overweight has not been well described. The objective of this study was to test the independent associations of sleep duration and problems with overweight risk in children.
METHODS. Data from the National Institute of Child Health and Human Development Study of Early Child Care and Youth Development were analyzed. In 3rd and 6th grades, sleep duration and problems were obtained by maternal report, and height and weight were measured, with overweight defined as a BMI of ≥95th percentile for age and gender. Logistic regression evaluated the association of sleep duration and problems with overweight at 6th grade cross-sectionally adjusting for gender, race, and maternal education. Additional covariates tested individually included the level of chaos at home, the quality of the home environment, the lax-parenting subscale score of the Raising Children Checklist, and the Child Behavior Checklist internalizing and externalizing subscale scores. Logistic regression also evaluated the relationship of sleep duration at 3rd grade and overweight at 6th grade, adjusting for gender, race, maternal education, and the child's BMI z score in 3rd grade.
RESULTS. Of 785 children, 50% were male, 81% were white, and 18% were overweight in 6th grade. Shorter sleep duration in 6th grade was independently associated with a greater likelihood of overweight in 6th grade. Shorter sleep duration in 3rd grade was also independently associated with overweight in 6th grade, independent of the child's weight status in 3rd grade. Sleep problems were not associated with overweight.
CONCLUSION. One preventive approach to overweight may be to ensure adequate sleep in childhood.