bluuebunny/crossref_metadata_2025 huggingface dataset:
Results of the IPC Copper Foil Ductility Round-Robin Study
Authors: Engelmaier W
Published: December 2008

A round-robin test program has been carried out to (1) develop typical and establish minimum ductility values for the copper foil classes in the Institute for Interconnecting and Packaging Electronic Circuits (IPC) Specification on Copper Foil for Printed Wiring Applications (IPC-CF-150E), (2) determine the precision and accuracy of IPC Test Method on Flexural Fatigue and Ductility, Foil, (IPC-TM-2.4.2.1), and ASTM Method for Ductility Testing of Metallic Foil (E 796), and (3) determine the bending fatigue behavior of the copper foils. This report contains a compilation of the results from seven test laboratories for copper foils from seven classes (both electrodeposited and wrought), four weights (thicknesses), and five vendors. The results show that the samples submitted by the vendors pass the recommended minimum ductility values, sometimes with large margins. The test method shows high precision typically resulting in sample standard deviations of less than 10% of the mean. The lab-to-lab accuracy shows a somewhat larger than expected test procedure dependence, in particular because of thickness measurement errors and deviations from established procedure. For both severe flexing or continuous high-cycle fatigue applications, annealed wrought copper foil is the best choice because of its initial high isotropic ductility, which gives the ability to sustain severe bending and low-cycle flexing, and its strain-hardening behavior during extended cycling, which results in a cyclicly increasing tensile strength and produces extended high-cycle fatigue lives.
Shear Testing of Fiber Reinforced Metal Matrix Composites
Authors: Pindera M-J
Published: December 2008

This paper outlines the elements of a combined experimental/analytical methodology for accurate shear characterization of unidirectional composites in the linear and nonlinear range, with particular attention devoted to metal matrix composites. It is illustrated that consistent results can be obtained for a large class of composites from two commonly employed shear test methods currently in use by composites researchers when the influence of various factors that affect the determination of the actual shear response is properly analyzed. These factors include the effects of material anisotropy, specimen geometry, manner of load introduction, and test fixture design on the stress and deformation fields in the test section of off-axis and losipescu specimens. Common errors associated with the measurement of deformation fields and calculation of stress fields are discussed and quantified. Particular problems in the determination of the shear response of unidirectional boron/aluminum using the losipescu test are illustrated and discussed.
Fatigue Testing and Damage Development in Continuous Fiber Reinforced Metal Matrix Composites
Authors: Johnson WS
Published: December 2008

Continuous fiber reinforced metal matrix composites (MMC) are projected for use in high-temperature stiffness critical parts that will be subjected to cyclic loadings. This paper presents a general overview of the fatigue behavior of MMC. The objectives of this paper are twofold. The first objective is to present experimental procedures and techniques for conducting a meaningful fatigue test to detect and quantify fatigue damage in MMC. These techniques include interpretation of stress-strain responses, acid etching of the matrix, edge replicas of the specimen under load, radiography, and micrographs of the failure surfaces. In addition, the paper will show how stiffness loss in continuous fiber reinforced metal matrix composites can be a useful parameter for detecting fatigue damage initiation and accumulation. Second, numerous examples of how fatigue damage can initiate and grow in various MMC are given. Depending on the relative fatigue behavior of the fiber and matrix, and the interface properties, the failure modes of MMC can be grouped into four categories: (1) matrix dominated, (2) fiber dominated, (3) self-similar damage growth, and (4) fiber/matrix interfacial failures. These four types of damage will be discussed and illustrated by examples with the emphasis on the fatigue of unnotched laminates.
Leaching Characteristics of Construction Materials and Stabilization Products Containing Waste Materials
Authors: van der Sloot HA , de Groot GJ , Wijkstra J
Published: December 2008

In this work, several construction materials prepared with an admixture of waste material and various stabilized waste products have been subjected to leaching studies in order for the leaching behavior of trace elements from these materials to be characterized. Static and dynamic leach tests have been applied, in which the specimen to be studied is fully immersed in demineralized water. Often the leaching process is governed by outward diffusion of constituents dissolved in the pore water. In some cases, dissolution from the surface of the product is most prominent, and in some materials short-term surface release has been observed. Groups of materials can be distinguished with similarities in the leaching behavior of trace elements.

The alkalinity of the material, the open porosity of the product, and the surface-to-volume ratio prove to be important factors in controlling the release of potential hazardous elements from materials containing waste products. In these studies, leach parameters of trace elements are related to those of sodium. Since the interaction of sodium with the solid phase is usually small, sodium can be used as an indicator for the tortuosity of the product. Elements leached from cement-based waste products are mainly anionic species, like MoO42-, BO33-, VO43-, F-, and SO42-, whereas leaching of metals such as copper, cadmium, zinc, and lead is limited due to the high pH in the pore solution. The leaching experiments have been verified by scanning electron microscopy for major components on field samples and by measuring depth profiles in waste products for trace constituents using an apparatus developed for this purpose.
Effects of Body-Checking in the Pee-Wee (12 and 13 Years Old) Division in the Province of Quebec
Authors: Régnier G , Boileau R , Marcotte G , Desharnais R , Larouche R , Bernard D , Roy M-A , Trudel P , Boulanger D
Published: December 2008

This paper documents the effects related to the introduction of body-checking in ice hockey for players of 12 and 13 years old (Pee-Wee Division). Four different studies were conducted on 49 teams of Pee-Wee hockey players: 28 teams played in a league allowing body-checking, and 21 teams played in a league banning body-checking. The topics studied were (1) the attitudes and beliefs of coaches, parents, and players about body-checking; (2) the morphological and biomechanical differences among Pee-Wee players; (3) the numbers and types of penalties within Pee-Wee leagues playing with and without body-checking; and (4) the injury rate within Pee-Wee leagues playing with and without body-checking. Among the most interesting results were the facts that, in that age category, some players were found to be twice as heavy and twice as strong as others. Larger players could exert an impact force 70% greater than those exerted by smaller players. Contrary to popular belief, playing without body-checking resulted in fewer “hostile aggression penalties.” Finally, the rate of fractures was twelve times greater for the league allowing body-checking.

The results are discussed in the light of regulating actions taken in Quebec and the Canadian provinces toward body-checking in the Pee-Wee Division.
A Heat Transfer Analysis of Metal Fasteners in Low-Slope Roofs
Authors: Burch DM , Shoback PJ , Cavanaugh K
Published: December 2008

The heat transfer through cylindrical metal fasteners with metal caps, in low-slope roofs having metal and wood decking, is analyzed using finite-difference theory. For a representative case of 5.4 fasteners/m2 (4.5 fasteners/yd2), metal fasteners were found to reduce the overall thermal resistance of low-slope roofs with metal decking from 3 to 8% for insulation thicknesses ranging from 25 to 150 mm (1 to 6 in.). The effect of metal fasteners on the overall thermal resistance of low-slope roofs with wood decking was found to be about one-half their effect on roofs with metal decking. The use of plastic instead of metal caps on the metal fasteners reduced the thermal bridging of the individual metal fastener by 44%.
Observations on Atmospheric Corrosion Made of Architectural Copper Work at Yale University
Authors: Fishman HB , Darling BP , Wooten JR
Published: December 2008

A six-year study of roofing and flashing of various buildings including many at Yale University was conducted. The buildings had architectural copper, which was in service for up to 100 years or more. There was great variety of usages. Various components had failed while others were salvageable and still others only slightly worn. Because of the varying degree of wear we attempted to find the reasons for this degradation. Methods of installation, location, orientation, and other factors were evaluated. Samples were taken, measured, and photographed. Some samples surfaced with lead faired better than some with no coatings. Lead coated copper on vertical surfaces did not wear as rapidly as on flat surfaces. Contaminants in the atmosphere appeared to increase rates of corrosion. Asphaltic or aluminum bearing repair materials produced adverse affects and were ineffective in stopping the leaks. Lead coating and patina were important in reducing the rate of aging. Size and method of restraint were also important. Large panels were subject to fatigue and cracking. Pitting at soldered seams was frequently observed. Photographs depict various sequences. Formation of patinas in corrosion products were observed. Lead coated copper was found to turn green after approximately 25 to 35 years of exposure on horizontal surfaces. Vertical surfaces remained grey or white. Reduction of serviceability depended more on method of installation, detailing, and design, than on the corrosion-induced deterioration.
Influence of Temperature and Pressure on the Explosion Characteristics of Dust/Air and Dust/Air/Inert Gas Mixtures
Authors: Wiemann W
Published: December 2008

The explosion characteristics of dusts change with the initial temperature. The maximum explosion pressure, the lower explosion limit, and the oxygen limit concentration decrease as the initial temperature rises. The normalized pressure rise rate (KSt value) does not show as clearly the influence of initial temperature. The explosion characteristics of dusts also change with the initial pressure. As the initial pressure is increased, there is a proportional increase of the maximum explosion pressure, the KSt value, and the lower explosion limit. The initial pressure rise also leads to a small decrease of the oxygen limit concentration.
An Instrumentation System to Automate the Analysis of Fuel-Spray Images Using Computer Vision
Authors: Oberdier LM
Published: December 2008

An intelligent instrumentation system is being implemented to analyze images stored during pulsed laser illumination of fuel sprays. Images are stored on magnetic video disk during the experiment and later analyzed with a system consisting of a commercial image processor and a minicomputer. The system employs computer vision algorithms to reduce the effects of shading and to segment candidate droplets from each image. Pattern recognition methods will be used to extract features from each droplet and to reject those which are not in the sample volume. The final output of the system is an accumulation of droplet size distributions at various sample points in the spray.
Ion Implantation for Deep (> 100 μm) Buried Layers
Authors: Fahrner WR , Bräunig D , Knoll M , Laschinski JR
Published: December 2008

The high energy implanter VICKSI is described. Silicon, germanium, gallium arsenide, quartz, and glasses are implanted. Ions are C, N, O, B, and the noble gases. Bare wafers as well as finished devices are used. Characterization is done by: (i) the two point spreading resistance, (ii) the I(V)-I(x)-dI/dx conversion of the two leakage currents of implanted thyristors, (iii) optical absorption of implanted glass, and (iv) the optical reflectivity. Dose and energy dependencies for the induced damage are studied with all four methods. Two peaks are observed for a variety of Si targets (wafer and device), ions, or measurement techniques. The peaks are often hidden behind the background damage and emerge for higher annealing temperatures only. The maxima of the dI/dx vs. x damage profiles are plotted as a function of 1/kT (T being the measurement temperature). The slope −Ea =0.72 eV suggests the creation of E-centers. Damage, ionization, and particle profiles are compared with Monte Carlo data. The fit quality varies between excellent and poor. The discrepancies are attributed to the lack of reliable data for the electronic straggling in the energy range beyond 10 MeV.
First-Ply Failure of Graphite/Epoxy Laminates
Authors: Kistner MD , Whitney JM , Browning CE
Published: December 2008

In situ transverse-ply failure in AS-4/3502 graphite/epoxy laminates is investigated by determining crack density as a function of laminate axial strain. These results are then related to laminate stress-strain response. Results show that plateaus in either the longitudinal or transverse stress-strain curve are associated with a significant increase in transverse-ply crack density. Stress analysis reveals a departure of inplane stresses from classical lamination theory near free edges. These stresses are found to be a function of laminate-ply orientations and stacking sequence. Thus, the onset of transverse-ply cracking may be influenced by the free edge in a standard tensile coupon.
Effect of Direction of Approach to Temperature on the Delayed Hydrogen Cracking Behavior of Cold-Worked Zr-2.5Nb
Authors: Ambler JFR
Published: December 2008

The delayed hydrogen cracking behavior of cold-worked Zr-2.5Nb at temperatures above about 423 K depends upon the direction of approach to test temperature. Cooling to the test temperatures results in an increase in crack growth rate, da/dt, with increase in temperature, given by the following Arrhenius relationship da/dt = 6.86 × 10−1 exp(−71500/RT) Heating from room temperature to the test temperature results in the same increase in da/dt with temperature, but only up to a certain temperature, TDAT. The temperature, TDAT, increases with the amount of hydride precipitated during cooling to room temperature, prior to heating, and with cooling rate. The results obtained can be explained in terms of the Simpson and Puls model of delayed hydrogen cracking, if the hydride precipitated at the crack tip is initially fully constrained and the matrix hydride loses constraint during heating.
Effects of Strain Aging in the Unloading Compliance J Test
Authors: Miglin MT , Van Der Sluys WA , Futato RJ , Domian HA
Published: December 2008

The behaviors of two heats of SA 515 Grade 70 in the unloading compliance J test were compared. Tensile properties were measured for both heats of material; one heat was found to be susceptible to dynamic strain aging. This heat also exhibited a steeper drop in the slope of the JI-R curve with increasing temperature, and serrated flow during the high-temperature J tests. The magnitude of the serrations varied during each test and with changes in loading displacement rate. Comparison with data from other carbon steels and weld metals showed that a large JIc drop with increasing temperature was associated with a large drop in ductility. J tests of strain-aging susceptible materials also showed a marked decrease in load drop from relaxation and peaks in load upon reloading at temperatures at the lower end of the temperature range of dynamic strain aging.
Influence of Mortar Materials on the Flexural Tensile Bond Strength of Block and Brick Masonry
Authors: Gazzola E , Bagnariol D , Toneff J , Drysdale RG
Published: December 2008

This paper reports on 475 tests for the influence of mortar materials on the flexural tensile strength of brick and block masonry for tension normal to the bed joints. The bond wrench testing technique was used to test each joint of the prisms. The results indicated significant decreases in tensile bond for mortars made with portland cement and masonry cement instead of portland cement and lime. Tests using sand with a gradation near the middle of the gradation limits (sieved concrete sand) and the available masonry sand that has more than the maximum percent passing a 600-μm (No. 30) sieve showed that the masonry sand produced slightly better tensile bond. In addition, flexural tensile bond strengths from both laboratory- and field-prepared prisms were compared with results obtained by removing bricks from the top of a brick wall. The average strengths and the influence of variability are discussed in terms of behavior and in terms of possible design code approaches.
New Concepts for Measuring Flame Spread Properties
Authors: Quintiere JG , Harkleroad MT
Published: December 2008

An experimental procedure is described which can be used to derive data relevant to the prediction of ignition and flame spread on materials. This procedure offers a direct method for determining material property data suitable for use in mathematical fire models. The apparatus utilizes a radiant heat source capable of supplying up to 6.5 W/cm2 to a vertically oriented specimen. The test results pertain to piloted ignition of a vertical sample under constant and uniform irradiation and to lateral flame spread on a vertical surface due to an external applied radiant heat flux. The results can be used to display the maximum velocity and ignition time as a function of irradiance. Critical or minimum irradiances for spread and ignition are determined. An empirical correlation, based on heat conduction principles, is found to correlate the ignition data and also provides a more general interpretation for the flame spread results. Further analyses of the data yield effective values for the thermal inertia of the material (kρc), its ignition temperature, and a parameter related to flame temperature. These parameters appear to be phenomenological constants for each material, rather than factors dependent on the apparatus. Results are presented for a wide range of materials. Suggestions for extending the results to other flame spread conditions are presented.
ΔK-Dependency of Fatigue Growth of Single and Mixed Mode Cracks Under Biaxial Stress
Authors: Kitagawa H , Yuuki R , Tohgo K , Tanabe M
Published: December 2008

A comprehensive fracture mechanics study has been carried out on the fatigue crack growth under various biaxial stress conditions. Fatigue tests have been conducted on a high-cycle biaxial fatigue test facility and a cruciform flat specimen of a weldable structural steel with a center crack parallel to one load axis or a slant crack.

The effects of biaxial stresses have been investigated on the fatigue crack growth properties ΔKI-da/dN, the threshold conditions ΔKIth, and the crack closure behavior.

If a crack is large and stress level is low, no effect of biaxial stress appears. However significant effects of biaxial stress appear where a crack is small and stress level is high.

The mixed mode cracks were realized by a series of fatigue tests started from a slant crack in a cruciform specimen, where a longer bent crack or a branched crack appeared. It is found that such a nonstraight crack follows along the direction where ΔKII = 0 and the ΔKI-da/dN relations coincide with those for a straight crack under single KI mode.
Low Cycle Fatigue Properties of a 1045 Steel in Torsion
Authors: Leese GE , Morrow J
Published: December 2008

A method of performing torsional low cycle fatigue tests on thin-walled tubular specimens is described. Shear strains are measured and controlled using an internally mounted rotary variable differential transducer (RVDT). Test results for a 1045 hot-rolled and normalized steel are discussed.

As in the case of uniaxial fatigue analysis, power law relationships are assumed in the elastic strain-life, plastic strain-life, and stress-plastic strain functions. From this analysis, the fatigue strength and ductility exponents and coefficients in torsion are determined, as well as the cyclic strain hardening exponent and strength coefficient in torsion. These properties are compared to those obtained in uniaxial fatigue tests of the same steel. The question of whether the cyclic strain hardening, fatigue strength, and fatigue ductility exponents are stress state dependent is specifically addressed. This is one of the fundamental issues that must be resolved if uniaxial fatigue properties are to be used to analytically predict multiaxial fatigue behavior.
Designing to Minimize Peel Stresses in Adhesive-Bonded Joints
Authors: Hart-Smith LJ
Published: December 2008

The same analyses that show how severe the peel stresses can be in adhesively bonded test coupons indicate that those stresses can be reduced to insignificance in structurally configured joints. The successful design of adhesively bonded joints is shown to require the use of adequately long and thin overlaps to ensure that the development of parasitic peel stresses is suppressed, allowing the joint to develop the full shear strength of the adhesives or, better yet, the full strength of the adherends outside the bonded joint. The joint configurations discussed include single-lap joints, single-strap joints, double-lap joints, and skin-to-stiffener joints. The material presented includes both parametric solutions and specific joint analyses to quantify the issues.
Moisture and Temperature Effects on the Mixed-Mode Delamination Fracture of Unidirectional Graphite/Epoxy
Authors: Russell AJ , Street KN
Published: December 2008

The critical strain energy release rates for interlaminar fracture of unidirectional graphite/epoxy, both from a sharp notch and as a function of crack extension, were determined experimentally for combined tensile/shear loadings. Based on well-founded compliance techniques, a substantial database was generated over the temperature range −50°C to 100°C for both dry and moisture-saturated states. The fracture energy of the unreinforced epoxy matrix material was also measured. Initiation energies for delamination increased as the proportion of shear loading increased and as the temperature was lowered but were insensitive to moisture content. The fracture resistance to crack extension increased under tensile dominated loadings with both temperature and moisture content but remained constant for high shear loadings. The applicability of various mixed-mode fracture criteria to both the present data and to available literature data is examined. The Wu fracture model was modified to take into account plane strain conditions appropriate to delamination. Crack growth resistance behavior is discussed in terms of the micromechanisms occurring close to the crack tip.
The Use of Stitching to Suppress Delamination in Laminated Composites
Authors: Mignery LA , Tan TM , Sun CT
Published: December 2008

The effect of stitching on edge delamination and ultimate strength in graphite/epoxy laminates is investigated. Study is done on three different graphite/epoxy layups: [±30/0]s, [±30/90]s, and [±45/02/902]s. Progression of delamination is monitored using di-iodobutane enhanced X-radiography. Results show that stitching effectively arrests delamination, but has varying effects on tensile strength. A two-dimensional finite element is used to calculate interlaminar normal stress and strain energy release rate for stitched and unstitched laminates. The introduction of stitching causes little change in interlaminar normal stress. However, it reduces the strain energy release rate as the delamination crack approaches the stitch line.
Evaluation and Prevention of Water Damage to Asphalt Pavement Materials
Authors: Ruth BE
Published: December 2008

Description

Papers examine methods for identifying and evaluating stripping; laboratory evaluation of the effects of moisture, anti-stripping, additives, and environmental conditioning; and the use of lime additives.
Epidemiology of Neonatal Early-onset Sepsis
Authors: Puopolo Karen M.
Published: December 2008

Neonatal early-onset sepsis (EOS) continues to be a significant source of morbidity and mortality among newborns, especially among very-low birthweight infants. Epidemiologic risk factors for EOS have been defined, and considerable resources are devoted to the identification and evaluation of infants at risk for EOS. The widespread implementation of intrapartum antibiotic prophylaxis for the prevention of early-onset neonatal group B Streptococcus (GBS) disease has reduced the overall incidence of neonatal EOS and influenced the microbiology of persistent early-onset infection. Most early-onset neonatal GBS disease now occurs in preterm infants or in term infants born to mothers who have negative GBS screening cultures. Ongoing clinical challenges include reassessment of clinical risk factors for EOS in the era of GBS prophylaxis; more accurate identification of GBS-colonized women; and continued surveillance of the impact of GBS prophylaxis practices on the microbiology of EOS, particularly among very low-birthweight infants.
InvasiveKingella kingaeInfections in Children: Clinical and Laboratory Characteristics
Authors: Dubnov-Raz Gal , Scheuerman Oded , Chodick Gabriel , Finkelstein Yaron , Samra Zmira , Garty Ben-Zion
Published: December 2008

OBJECTIVE. Kingella kingae, a Gram-negative coccobacillus, is being increasingly recognized as an invasive pathogen in children, causing mainly bacteremia and arthritis; however, there have been only a few studies on K kingae infections to date, mostly small-scale series. The aim of this study was to report our experience with invasive K kingae infections in children who were hospitalized at a major tertiary medical center in Israel.

METHODS. The medical charts of 62 children with proven invasive K kingae infections were reviewed: 42 with positive blood culture results and 20 with positive synovial fluid culture results.

RESULTS. Most infections occurred among previously healthy children aged 5 to 22 months. Eighty percent had a mild concurrent illness of the respiratory or gastrointestinal tract. A chronic underlying disease was documented in 19% of the 1- to 15-year-old children with bacteremia. Three patients had persistent bacteremia, identified by 2 positive blood cultures drawn 1 to 4 days apart. Four (10%) patients from the bacteremia group had endocarditis, and 2 required emergency cardiac surgery. Only a mild-to-moderate elevation of serum inflammatory markers was noted except for patients with endocarditis or a prolonged course of arthritis. Patients with bacteremia received a diagnosis significantly later than those with arthritis, with no other between-group differences in age, month of disease onset, and inflammatory marker levels. All K kingae isolates were resistant to vancomycin and clindamycin.

CONCLUSIONS. Our large series indicates that invasive K kingae infections occur in previously healthy children, mostly during the first 2 years of life; affected older children usually have an underlying medical condition. The infection generally elicits only a mild inflammatory response unless accompanied by endocarditis. Despite its low virulence, K kingae might cause a life-threatening heart disease that requires emergent, aggressive treatment.
Elevated Blood Pressure, Race/Ethnicity, and C-Reactive Protein Levels in Children and Adolescents
Authors: Lande Marc B. , Pearson Thomas A. , Vermilion Roger P. , Auinger Peggy , Fernandez Isabel D.
Published: December 2008

OBJECTIVE. Adult hypertension is independently associated with elevated C-reactive protein levels, after controlling for obesity and other cardiovascular risk factors. The objective of this study was to determine, with a nationally representative sample of children, whether the relationship between elevated blood pressure and C-reactive protein levels may be evident before adulthood.

METHODS. Cross-sectional data for children 8 to 17 years of age who participated in the National Health and Nutrition Examination Survey between 1999 and 2004 were analyzed. Bivariate analyses compared children with C-reactive protein levels of >3 mg/L versus ≤3 mg/L with respect to blood pressure and other cardiovascular risk factors. Multivariate linear regression was used to evaluate the relationship between elevated blood pressure and C-reactive protein levels.

RESULTS. Among 6112 children, 3% had systolic blood pressure of ≥95th percentile and 1.3% had diastolic blood pressure of ≥95th percentile. Children with C-reactive protein levels of >3 mg/L had higher systolic blood pressure, compared with children with C-reactive protein levels of ≤3 mg/L (109 vs 105 mm Hg). Obesity, high-density lipoprotein cholesterol levels of <40 mg/dL, and Hispanic ethnicity were independent predictors of elevated C-reactive protein levels. Diastolic blood pressure did not differ between groups. Linear regression analyses showed that systolic blood pressure of ≥95th percentile was independently associated with C-reactive protein levels in boys but not girls. Subset analyses according to race/ethnicity demonstrated that the independent association of elevated systolic blood pressure with C-reactive protein levels was largely limited to black boys.

CONCLUSIONS. These data indicate that there is interplay between race/ethnicity, elevated systolic blood pressure, obesity, and inflammation in children, a finding that has potential implications for disparities in cardiovascular disease later in life.
Sleep Hygiene for Children With Neurodevelopmental Disabilities
Authors: Jan James E. , Owens Judith A. , Weiss Margaret D. , Johnson Kyle P. , Wasdell Michael B. , Freeman Roger D. , Ipsiroglu Osman S.
Published: December 2008

Sleep disturbances in children with neurodevelopmental disabilities are common and have a profound effect on the quality of life of the child, as well as the entire family. Although interventions for sleep problems in these children often involve a combination of behavioral and pharmacologic strategies, the first line of treatment is the promotion of improved sleep habits or “hygiene.” Despite the importance of sleep-hygiene principles, defined as basic optimal environmental, scheduling, sleep-practice, and physiologic sleep-promoting factors, clinicians often lack appropriate knowledge and skills to implement them. In addition, sleep-hygiene practices may need to be modified and adapted for this population of children and are often more challenging to implement compared with their healthy counterparts. This first comprehensive, multidisciplinary review of sleep hygiene for children with disabilities presents the rationale for incorporating these measures in their treatment, outlines both general and specific sleep-promotion practices, and discusses problem-solving strategies for implementing them in a variety of clinical practice settings.
Disagreement in Parent and Primary Care Provider Reports of Mental Health Counseling
Authors: Brown Jonathan D. , Wissow Lawrence S.
Published: December 2008

OBJECTIVES. The goals were to examine disagreement in primary care provider and parent reports of mental health counseling and to determine whether disagreement was associated with provider, parent, youth, and visit characteristics.

METHODS. Directly after 749 visits to 54 pediatric primary care providers in 16 practices, the parents of youths 5 to 16 years of age and the providers independently reported whether mental health counseling was provided. The parent also reported child mental health symptoms, the reason for the visit, and his or her attitudes about receiving treatment for child mental health problems in primary care. The provider reported confidence in his or her mental health treatment skills, burden and beliefs associated with treating mental health problems, and the accessibility of mental health specialists.

RESULTS. Providers reported delivering counseling during 31.9% of visits (n = 239), whereas parents reported receiving counseling during only 11.4% of visits (n = 86). Parents did not report receiving counseling during 74.8% of the visits in which the provider reported delivering counseling; this was more common when the parent was seeking help for a mental health problem, when the provider reported greater burden associated with treating mental health problems, and when the youth had more mental health symptoms or was of other race/Hispanic. Provider report of counseling in the absence of parent report of counseling was less common when the provider had greater access to mental health specialists.

CONCLUSIONS. Parents often did not report that the counseling delivered in primary care was mental health treatment. Counseling that is not perceived as mental health treatment may fail to meet parent expectations for care or fail to help parents identify mental health problems.
“You Get What You Get”: Unexpected Findings About Low-Income Parents' Negative Experiences With Community Resources
Authors: Silverstein Michael , Lamberto Jacqueline , DePeau Kristina , Grossman David C.
Published: December 2008

CONTEXT. Community-based resources are considered a critical part of the American health care system. However, studies evaluating the effectiveness of such resources have not been accompanied by rigorous explorations of the perceptions or experiences of those who use them.

OBJECTIVES. We aimed to understand and classify types of negative perceptions that low-income parents have of community resources. This objective originated from a series of unexpected findings that emerged during the analysis of qualitative data that were initially collected for other purposes.

METHODS. We conducted in-depth qualitative interviews with urban low-income parents. Themes emerged through a grounded theory analysis of coded interview transcripts. Interviews took place in 2 different cities as part of 2 studies with distinct objectives.

RESULTS. We completed 41 interviews. Informants often perceived their interactions with people and organizations as a series of trade-offs, and often perceived important choices as decisions between 2 suboptimal options. Seeking help from community resources was seen in that context. The following specific themes emerged: (1) engaging with services sometimes meant subjecting oneself to requirements perceived as unnecessary and, in the extreme, having to adopt the value systems of others; (2) accepting services was sometimes perceived as a loss of control over one's surroundings, which, in turn, was associated with feelings of sadness, helplessness, or stress; (3) individuals staffing community agencies were sometimes seen as judgmental or intrusive, and when many services were accessed concurrently, information sometimes became overbearing or a source of additional stress; and (4) some services or advice received as part of such services were perceived as unhelpful because they were too generic or formulaic.

CONCLUSIONS. Our data suggest that definable patterns of negative perceptions of community resources may exist among low-income parents. Quantifying these perceptions may help improve the client-centeredness of such organizations and may ultimately help reduce barriers to engagement.
Incidence and Diagnosis of Thrombosis in Children With Short-Term Central Venous Lines of the Upper Venous System
Authors: Hanslik Andreas , Thom Katharina , Haumer Markus , Kitzmüller Erwin , Albinni Suleima , Wolfsberger Margarita , Salzer-Muhar Ulrike , Male Christoph
Published: December 2008

OBJECTIVES. Deep venous thrombosis in children is frequently related to central venous lines. Study objectives were to determine objectively the incidence of deep venous thrombosis in children with short-term central venous lines and to assess the diagnostic value of venography, venous ultrasonography, and echocardiography, in a prospective cohort study.

METHODS. Consecutive children with congenital heart disease requiring short-term central venous lines in the upper venous system were screened systematically for deep venous thrombosis by using venography, venous ultrasonography, and echocardiography, according to standardized protocols.

RESULTS. The study population consisted of 90 children (median age: 2.7 years; range: birth to 18 years). Most central venous lines (97%) were located in the jugular veins. The overall incidence of deep venous thrombosis was 25 cases (28%) among 90 children. Venography identified deep venous thrombosis located in the subclavian and central veins but missed most deep venous thrombosis in the jugular veins. Venous ultrasonography had good sensitivity in the jugular veins but did not detect deep venous thrombosis in central veins. Echocardiography detected only 1 case of central deep venous thrombosis.

CONCLUSIONS. The incidence of central venous line-related deep venous thrombosis in children with short-term central venous lines is high and comparable to reports for children with long-term central venous lines. Sensitivities of venography, venous ultrasonography, and echocardiography in children vary depending on the affected venous segment. A combination of diagnostic tests is required for sensitive detection of central venous line-related deep venous thrombosis in the upper venous system.
Pseudoephedrine Use Among US Children, 1999–2006: Results From the Slone Survey
Authors: Vernacchio Louis , Kelly Judith P. , Kaufman David W. , Mitchell Allen A.
Published: December 2008

OBJECTIVE. Pseudoephedrine, a decongestant found in many cough-and-cold and allergy medications, has been associated with deaths and adverse events in young children; however, the absolute risks of pediatric pseudoephedrine use are difficult to assess because the number of children exposed on a population basis and typical patterns of use are unknown. In addition, use may be changing because of the Combat Methamphetamine Epidemic Act of 2005, which limited pseudoephedrine availability. We sought to describe the prevalence and patterns of pseudoephedrine use among US children and to assess any change since the 2005 law took effect.

METHODS. We analyzed data on pseudoephedrine use among 4267 children who were aged 0 to 17 years and enrolled from 1999 to 2006 in the Slone Survey, a national random-digit-dial telephone survey of medication use in the US population.

RESULTS. Overall, 214 children took pseudoephedrine in a given week. Use was highest for children who were younger than 2 years. Sixteen children (7.5% of users) took >1 pseudoephedrine-containing product within the same week, including 6 children who were younger than 2 years. Of the pseudoephedrine products used, most were multiple-ingredient liquids (58.9%) and multiple-ingredient tablets (24.7%). Fifty-two children (25.0% of users) took pseudoephedrine for >1 week, including 7 children who were younger than 2 years. Use in 2006 (2.9%) was significantly lower than in 1999–2005 (5.2%).

CONCLUSIONS. Pseudoephedrine exposure, mostly in the form of multiple-ingredient products, is common among US children, especially children who are younger than 2 years, who are at the highest risk for toxicity and for whom safe dosing recommendations are lacking. Concerning patterns of use include taking >1 pseudoephedrine-containing product concurrently and using pseudoephedrine for extended periods. Pediatric pseudoephedrine use seems to be declining since the institution of the 2005 Combat Methamphetamine Epidemic Act.
Genomic Imbalances in Neonates With Birth Defects: High Detection Rates by Using Chromosomal Microarray Analysis
Authors: Lu Xin-Yan , Phung Mai T. , Shaw Chad A. , Pham Kim , Neil Sarah E. , Patel Ankita , Sahoo Trilochan , Bacino Carlos A. , Stankiewicz Pawel , Kang Sung-Hae Lee , Lalani Seema , Chinault A. Craig , Lupski James R. , Cheung Sau W. , Beaudet Arthur L.
Published: December 2008

OBJECTIVES. Our aim was to determine the frequency of genomic imbalances in neonates with birth defects by using targeted array-based comparative genomic hybridization, also known as chromosomal microarray analysis.

METHODS. Between March 2006 and September 2007, 638 neonates with various birth defects were referred for chromosomal microarray analysis. Three consecutive chromosomal microarray analysis versions were used: bacterial artificial chromosome–based versions V5 and V6 and bacterial artificial chromosome emulated oligonucleotide–based version V6 Oligo. Each version had targeted but increasingly extensive genomic coverage and interrogated >150 disease loci with enhanced coverage in genomic rearrangement–prone pericentromeric and subtelomeric regions.

RESULTS. Overall, 109 (17.1%) patients were identified with clinically significant abnormalities with detection rates of 13.7%, 16.6%, and 19.9% on V5, V6, and V6 Oligo, respectively. The majority of these abnormalities would not be defined by using karyotype analysis. The clinically significant detection rates by use of chromosomal microarray analysis for various clinical indications were 66.7% for “possible chromosomal abnormality” ± “others” (other clinical indications), 33.3% for ambiguous genitalia ± others, 27.1% for dysmorphic features + multiple congenital anomalies ± others, 24.6% for dysmorphic features ± others, 21.8% for congenital heart disease ± others, 17.9% for multiple congenital anomalies ± others, and 9.5% for the patients referred for others that were different from the groups defined. In all, 16 (2.5%) patients had chromosomal aneuploidies, and 81 (12.7%) patients had segmental aneusomies including common microdeletion or microduplication syndromes and other genomic disorders. Chromosomal mosaicism was found in 12 (1.9%) neonates.

CONCLUSIONS. Chromosomal microarray analysis is a valuable clinical diagnostic tool that allows precise and rapid identification of genomic imbalances and mosaic abnormalities as the cause of birth defects in neonates. Chromosomal microarray analysis allows for timely molecular diagnoses and detects many more clinically relevant genomic abnormalities than conventional cytogenetic studies, enabling more informed decision-making and management and appropriate assessment of recurrence risk.
Hydroxyurea for Sickle Cell Disease: A Systematic Review for Efficacy and Toxicity in Children
Authors: Strouse John J. , Lanzkron Sophie , Beach Mary Catherine , Haywood Carlton , Park Haeseong , Witkop Catherine , Wilson Renee F. , Bass Eric B. , Segal Jodi B.
Published: December 2008

CONTEXT. Hydroxyurea is the only approved medication for the treatment of sickle cell disease in adults; there are no approved drugs for children.

OBJECTIVE. Our goal was to synthesize the published literature on the efficacy, effectiveness, and toxicity of hydroxyurea in children with sickle cell disease.

METHODS. Medline, Embase, TOXLine, and the Cumulative Index to Nursing and Allied Health Literature through June 2007 were used as data sources. We selected randomized trials, observational studies, and case reports (English language only) that evaluated the efficacy and toxicity of hydroxyurea in children with sickle cell disease. Two reviewers abstracted data sequentially on study design, patient characteristics, and outcomes and assessed study quality independently.

RESULTS. We included 26 articles describing 1 randomized, controlled trial, 22 observational studies (11 with overlapping participants), and 3 case reports. Almost all study participants had sickle cell anemia. Fetal hemoglobin levels increased from 5%–10% to 15%–20% on hydroxyurea. Hemoglobin concentration increased modestly (∼1 g/L) but significantly across studies. The rate of hospitalization decreased in the single randomized, controlled trial and 5 observational studies by 56% to 87%, whereas the frequency of pain crisis decreased in 3 of 4 pediatric studies. New and recurrent neurologic events were decreased in 3 observational studies of hydroxyurea compared with historical controls. Common adverse events were reversible mild-to-moderate neutropenia, mild thrombocytopenia, severe anemia, rash or nail changes (10%), and headache (5%). Severe adverse events were rare and not clearly attributable to hydroxyurea.

CONCLUSIONS. Hydroxyurea reduces hospitalization and increases total and fetal hemoglobin levels in children with severe sickle cell anemia. There was inadequate evidence to assess the efficacy of hydroxyurea in other groups. The small number of children in long-term studies limits conclusions about late toxicities.
Blood Pressure and Heart Rate Patterns During Sleep Are Altered in Preterm-Born Infants: Implications for Sudden Infant Death Syndrome
Authors: Witcombe Nicole B. , Yiallourou Stephanie R. , Walker Adrian M. , Horne Rosemary S.C.
Published: December 2008

OBJECTIVE. Preterm infants are at an increased risk of sudden infant death syndrome, which may result from immature autonomic control of heart rate and blood pressure. Previous studies have demonstrated that preterm infants have altered heart rate and blood pressure control at term-equivalent age; however, little information is available beyond this age. The aim of this study was to determine the effect of preterm birth on heart rate and blood pressure control over the first 6 months of life after reaching term-equivalent age, including the age at which sudden infant death syndrome risk is increased, to understand the pathogenesis of sudden infant death syndrome.

METHODS. Preterm (n = 25) and term (n = 20) infants were studied longitudinally at 2 to 4 weeks', 2 to 3 months', and 5 to 6 months' term-corrected age by using daytime polysomnography. A photoplethysmographic cuff (Finometer) around the infant's wrist measured blood pressure during quiet and active sleep.

RESULTS. Blood pressure was lower in the preterm group during both quiet and active sleep at all ages studied. In contrast, there were no differences between groups in heart rate. Within the infants in the preterm group, blood pressure averaged lower at 2 to 3 months' corrected age compared with both 2 to 4 weeks' and 5 to 6 months' corrected age and was lower in quiet sleep compared with active sleep at all ages studied. Heart rate decreased with increasing age and was lower in quiet sleep compared with active sleep at 5 to 6 months' corrected age.

CONCLUSIONS. Sleep state and age affect heart rate and blood pressure patterns in prematurely born infants over the first 6 months of term-corrected age. It is notable that preterm infants had persistently lower blood pressure compared with age-matched term infants, signifying long-term alterations in cardiovascular control in infants born prematurely.