cssi/SciSciGPT-SciSciNet huggingface dataset:
Effect of finger ulnar deviation on gliding resistance of the flexor digitorum profundus tendon within the A1 and A2 pulley complex

Purpose To evaluate the effect of ulnar deviation of the finger on gliding resistance of the flexor digitorum profundus tendon within the A1 and A2 pulley complex. Methods Thirty-two human cadaveric fingers (index through small fingers) were used. The gliding resistance was measured at 5 different angles of ulnar deviation (0°, 15°, 30°, 45°, 60°). Results There was a significant increase in gliding resistance with increased ulnar deviation. The gliding resistances at 0°, 15°, 30°, 45°, and 60° of ulnar deviation were 0.40 ± 0.13 N, 0.44 ± 0.13 N, 0.55 ± 0.17 N, 0.74 ± 0.21 N, and 1.02 ± 0.30 N, respectively. The gliding resistance at 60° was significantly greater than at all other angles; 45° ulnar deviation had significantly higher gliding resistance than 0°, 15°, and 30°; and 30° ulnar deviation had significantly higher gliding resistance than 0°. Conclusions A greater angle of ulnar deviation causes higher gliding resistance during motion of the flexor digitorum profundus tendon within the A1 and A2 pulley complex. The gliding resistance increases significantly at angles greater than 30° of ulnar deviation. The increased tendon loading needed to overcome increased gliding resistance caused by ulnar deviation could result in a vicious cycle of progressive ulnar deviation. Although mild degrees of ulnar deviation may be well tolerated mechanically a reasonable therapeutic guideline might be to prevent deviation from exceeding 30°.
Life History of the Black Redhorse, Moxostoma duquesnei (Lesueur), in Missouri

Abstract The abundance of the black redhorse (Moxostoma duquesnei) within Missouri rivers appeared to be correlated with volume of flow: the greatest biomass occurred in streams with an annual average discharge of 500–600 cfs. The breeding behavior of the adult black redhorse is described. There was no parental care of the eggs. The body-scale relationship for the populations of each river was best represented by a combination of two straight lines. It is suggested that the break in the body-scale relationship was related to the attainment of sexual maturity. Black redhorse from the Big Piney River grew in length and gained in weight slightly faster than the black redhorse from the Niangua River. This difference in growth is attributed to a difference in intensity of harvest. Similarities existed between food items of black redhorse and fingerling smallmouth bass which may have been due to the smallmouth bass utilizing drift organisms from sucker feeding activities. Seasonal and daily movements of the bla...
D-serine improves dimensions of the sociability deficit of the genetically-inbred Balb/c mouse strain.

Abstract The Balb/c mouse strain shows quantitative deficits of sociability and is behaviorally-hypersensitive to MK-801 (dizocilpine), a noncompetitive NMDA receptor antagonist. D-Serine (560 mg/kg, intraperitoneally), a full agonist for the obligatory glycine co-agonist binding site on the NMDA receptor, increased the amount of time Balb/c mice spend in a compartment containing the enclosed social stimulus mouse and the amount of time Balb/c mice spend exploring (sniffing) an inverted cup containing the enclosed social stimulus mouse in a standard sociability apparatus. These effects of D-serine on the impaired sociability of the Balb/c mouse strain were not due to a “nonspecific” effect on locomotor activity; importantly, the locomotor activity of the Balb/c mouse strain decreases in the presence of an enclosed or freely-moving social stimulus mouse. The data suggest that dimensions of the impaired sociability of the Balb/c mouse strain may be improved by targeted NMDA receptor agonist interventions.
On the “hindrance” of 3− excitations induced by nuclear scattering

Abstract It has been reported that the excitation of low-lying 3 − states in nuclei by hadronic probes indicate much weaker transition strengths than are implied by the results of electromagnetic measurements. We demonstrate that this is a consequence of using the deformed optical potential model to analyze the hadronic scattering. The apparent hindrance disappears when a folding model is used. The discrepancy between the results of using the two models increases dramatically as the multipolarity of the transition increases, and we recommend the folding approach.
Assessment of oral implant mobility

Most of the implant literature suggests that successful dental implants are immobile and any detected mobility indicates implant failure. This study evaluated the ability of the Periotest instrument to measure implant mobility in a controlled in vitro model with a sample of 56 in vivo implants. In the in vitro portion of the study, implant model mobility was determined by an axial testing machine (0 to 5 N at 0.2 mm/minute) and the Periotest instrument. The comparison showed a high level of correlation (Pearson's r 0.984). The load that the Periotest placed on the implants during mobility measurements was approximately 5 N, depending on the compliance of the test object. The in vivo portion evaluated the range of mobility of 56 clinically successful endosseous implants. The range of mobility as determined by the Periotest instrument was -6 to +2. This range corresponds to an in vitro model displacement (5 N load) of 0.038 mm to 0.113 mm with a mean of 0.066 mm +/- 0.018 mm (SD). These data demonstrate that clinically successful implants are not immobile, but have a range of mobility.
Rapid design and prototyping of customized rehabilitation aids

Introduction There is a considerable variability in performance, form and function among the individuals of any population. Such variability creates a critical need for designing products that are specific to an individual. This process becomes even more important when the functional performance of the product is tied in to the individual's capabilities, as in the case of rehabilitation devices. In this article, we discuss the emergent technologies and their integration which will permit rapid customized design and manufacture of products, with some emphasis on the design of rehabilitation aids for individuals with physical disability (for example, prosthetic devices such as artificial limbs and orthoses).
Sex Differences In Response To Evaluative Feedback: A Field Study

We investigated sex differences in response to evaluative feedback among bank employees who were going through the annual performance evaluation process. Questionnaires were mailed to employees bef...
Matrix-to-fracture transfer functions derived from the data of oil recovery, and it's derivative and integral

It is demonstrated that using integrals, derivatives, and inflection points of the oil recovery data measured by imbibition tests on cores improves the accuracy of correlations of the matrix-to-fracture oil transfer data. The tri-exponential transfer functions with the present numerical approach yield a reliable technique to represent the experimental imbibition data. Accurately estimated function parameters allow the laboratory results to be scaled to field applications. Several issues pertaining to spontaneous imbibition as a recovery mechanism while waterflooding naturally fractured reservoirs are addressed. The contribution of the wettability and dead-end pores is also determined. The triple-exponential function for double-porosity systems is able to adjust to actual spontaneous imbibition trends observed in experiments conducted in naturally fractured cores. The analysis and interpretation of the results verify the considerations of the proposed mechanisms for fluid transfer from matrix to fracture.
Precomputed acceleration noise for improved rigid-body sound

We introduce an efficient method for synthesizing acceleration noise -- sound produced when an object experiences abrupt rigid-body acceleration due to collisions or other contact events. We approach this in two main steps. First, we estimate continuous contact force profiles from rigid-body impulses using a simple model based on Hertz contact theory. Next, we compute solutions to the acoustic wave equation due to short acceleration pulses in each rigid-body degree of freedom. We introduce an efficient representation for these solutions -- Precomputed Acceleration Noise -- which allows us to accurately estimate sound due to arbitrary rigid-body accelerations. We find that the addition of acceleration noise significantly complements the standard modal sound algorithm, especially for small objects.
5-Hydroxytryptamine2A receptor stimulation induces activator protein-1 and cyclic AMP-responsive element binding with cyclic AMP-responsive element-binding protein and Jun D as common components in cerebellar neurons.

Abstract Previous studies from our laboratory have demonstrated that stimulation of 5-hydroxytryptamine 2A receptors in rat cerebellar granule cells produces an increase in the levels of 5-hydroxytryptamine 2A receptor messenger RNA and binding sites, and that this up-regulation requires de novo RNA and protein synthesis. Here we showed that up-regulation of 5-hydroxytryptamine 2A receptor binding sites induced by stimulation with the 5-hydroxytryptamine 2A/2C receptor agonist, (±)-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane, is associated with an increase in the 5-hydroxytryptamine 2A receptor transcription rate. To examine the possible role of transcriptional activation in (±)-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane-induced 5-hydroxytryptamine 2A receptor up-regulation, we studied the effects of (±)-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane on transcription factor binding to activator protein-1 and cyclic AMP-responsive element DNA consensus sequences. We found that (±)-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane induces a time-dependent increase in activator protein-1 and cyclic AMP-responsive element transcription factor binding activity, which is blocked by 5-hydroxytryptamine 2A receptor antagonists. Similar to 5-hydroxytryptamine 2A receptor up-regulation, (±)-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane-induced activator protein-1 binding is suppressed by inhibitors of calmodulin and Ca 2+ /calmodulin-dependent kinases. The increased activator protein-1 binding is effectively competed by excessive activator protein-1 and cyclic AMP-responsive element sequences as well as endogenous activator protein-1 like sequences present in rat 5-hydroxytryptamine 2A receptor gene. Supershift assays revealed that cAMP-responsive element-binding protein and Jun D are common components of both activator protein-1 and cyclic AMP-responsive element binding complexes. (±)-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane also increased the level of phospho-cyclic AMP-responsive element-binding protein protein in a time-dependent manner. The binding of phospho-cyclic AMP-responsive element-binding protein transcription factor to the activator protein-1 site suggests that cyclic AMP-responsive element-binding protein may modulate the transcription of genes that contain activator protein-1 but lack cyclic AMP-responsive element site in their promoters, through interaction with the activator protein-1 site. The rat 5-hydroxytryptamine 2A receptor up-regulation may involve such a mechanism.
Oophorectomy versus salpingo-oophorectomy in Turner syndrome patients with Y-chromosome material: clinical experience and current practice patterns assessment

Abstract Background/purpose Gonadectomy is recommended in Turner syndrome (TS) patients with Y-chromosome material due to high risk of tumor in the dysgenetic gonads. No recommendations exist on whether concurrent salpingectomy should be performed. Methods A retrospective chart review of surgical procedure and histopathology in TS patients with Y-chromosome enrolled in a TS database was undertaken at Cincinnati Children's Hospital Medical Center. An electronic survey was sent to members of the International Pediatric Endosurgery Group to assess prevalent practice patterns and attitudes on gonadectomy and concurrent salpingectomy in this population. Results In March 2011, 12/158 (8%) TS girls (mean age 6.6years) enrolled in the database had TS with Y-chromosome. Gonadoblastoma was identified in 4/12 (33%) patients and 2/4 had malignant transformation to dysgerminoma and teratoma. Approach to gonadectomy was varied and 3/12 had concurrent salpingectomy. Fifty-four laparoscopic surgeons responded to the survey with no clear consensus on whether salpingectomy should be concurrently performed. Conclusions TS patients with Y-chromosome have an increased risk of gonadal tumor development and gonadectomy is recommended. While there is no consensus among pediatric laparoscopic surgeons on concurrent salpingectomy, it is reasonable to consider this combination procedure.
Interactions of DNA with divalent metal ions. III. Extent of metal binding: Experiment and theory

DNA with Mn2+ as the only counterion has been prepared, and the extent of the Mn2+ binding was determined under a variety of conditions through measurements of the proton relaxation enhancement of water. The total extent of Mn2+ binding per DNA phosphate is found to be 0.43 ± 0.04, independent of the metal ion concentration in the experimental range of 2.8 × 10−5 to 2.1 × 10−3M. The predictions of Manning's condensation theory and those obtained from solution of the generalized Poisson-Boltzmann equation regarding the extent of divalent ion binding to polyelectrolytes, in the presence and absence of monovalent counterions, are compared with one another and with the experimental results. Good agreement between the two theoretical approaches is found, with less than 14% variance in the predicted extent of binding over a large range of mono- and divalent ion concentrations. While the predictions of both theoretical approaches generally agree with the experimental results, some discrepancies are noted and their possible origins discussed.
Gene Therapy and Tissue Engineering in Sports Medicine

Treatment of sports injuries has improved through sophisticated rehabilitation programs, novel operative techniques, and advances in biomechanical research during the past two decades. Despite considerable progress, treatments remain limited due to poor healing capacity for anterior or posterior cruciate ligament rupture, central meniscal tear, cartilage lesions, and delayed bone fracture. New biological approaches seek to treat these injuries with growth factors to stimulate and hasten the healing process. Gene therapy using the transfer of defined genes such as those encoding growth factors represents a promising way to deliver therapeutic proteins to the injured tissue. Tissue engineering, which may eventually be combined with gene therapy, offers the potential to create tissues or scaffolds for regeneration of defects occurring from trauma.
Stress Levels of Glucocorticoids Inhibit LHβ-Subunit Gene Expression in Gonadotrope Cells

Increased glucocorticoid secretion is a common response to stress and has been implicated as a mediator of reproductive suppression upon the pituitary gland. We utilized complementary in vitro and in vivo approaches in the mouse to investigate the role of glucocorticoids as a stress-induced intermediate capable of gonadotrope suppression. Repeated daily restraint stress lengthened the ovulatory cycle of female mice and acutely reduced GnRH-induced LH secretion and synthesis of LH β-subunit (LHβ) mRNA, coincident with increased circulating glucocorticoids. Administration of a stress level of glucocorticoid, in the absence of stress, blunted LH secretion in ovariectomized female mice, demonstrating direct impairment of reproductive function by glucocorticoids. Supporting a pituitary action, glucocorticoid receptor (GR) is expressed in mouse gonadotropes and treatment with glucocorticoids reduces GnRH-induced LHβ expression in immortalized mouse gonadotrope cells. Analyses revealed that glucocorticoid repression localizes to a region of the LHβ proximal promoter, which contains early growth response factor 1 (Egr1) and steroidogenic factor 1 sites critical for GnRH induction. GR is recruited to this promoter region in the presence of GnRH, but not by dexamethasone alone, confirming the necessity of the GnRH response for GR repression. In lieu of GnRH, Egr1 induction is sufficient for glucocorticoid repression of LHβ expression, which occurs via GR acting in a DNA- and dimerization-independent manner. Collectively, these results expose the gonadotrope as an important neuroendocrine site impaired during stress, by revealing a molecular mechanism involving Egr1 as a critical integrator of complex formation on the LHβ promoter during GnRH induction and GR repression.
Effective and safe endoscopic reversal of nondysplastic Barrett's esophagus with thermal electrocoagulation combined with high-dose acid inhibition: a multicenter study.

Abstract Background: Barrett's esophagus is a metaplastic change in the esophageal lining with an increased risk for adenocarcinoma. Multiple endoscopic techniques have been applied in an effort to reverse Barrett's. This is a multicenter trial defining the efficacy and safety of multipolar electrocoagulation combined with high-dose acid inhibition. Methods: Patients with a 2- to 6-cm segment of Barrett's esophagus without dysplasia were enrolled at 3 centers. They were treated with omeprazole 40 mg twice daily and then with up to 6 sessions with electrocoagulation aimed at eliminating all the endoscopically apparent Barrett's. Four quadrant large-capacity biopsies every 2 cm were centrally assessed for residual intestinal metaplasia. Results: Fifty-eight patients reached the endpoint of failure of visual reversal of Barrett's after 6 treatment sessions or a 6-month follow-up after the last session. Eighty-five percent had visual reversal and 78% both visual and histologic reversal. Four patients had histologic evidence of residual intestinal metaplasia. Transient esophageal symptoms were common. One patient developed a stricture requiring dilation and one required overnight hospitalization for chest pain. Conclusions: The majority of patients with 2 to 6 cm of nondysplastic Barrett's esophagus can be safely reversed with this combination therapy. Long-term follow-up will be necessary to document the durability of the new squamous epithelium. (Gastrointest Endosc 2001;53:554-8.)
The Development of an Assessment of Interpersonal Violence for Individuals with Intellectual and Developmental Disabilities

Individuals with intellectual and developmental disabilities experience rates of interpersonal violence much higher than those in the general population. Not only do they face physical, sexual, emotional, and financial abuse, they also face additional forms of interpersonal violence specific to their disability and care. While rates of interpersonal violence experienced by people with disabilities exist in the literature, measurement of these rates has been widely divergent across the field of disabilities. Currently, there are no-known evidence-based measures of interpersonal violence for individuals with intellectual and developmental disabilities. This article describes the development of an assessment tool, the Interpersonal Violence Interview (IVI), to measure the number of incidents of interpersonal violence against people with intellectual and developmental disabilities. A Delphi technique was used in the development of the tool in order to reach consensus regarding the content of the assessment. The results show the IVI is a promising first step towards the development of an evidence-based measure of interpersonal violence for individuals with intellectual and developmental disabilities.
Product-line expansion and resource cannibalization

Abstract Diversification research argues that new products are more successful when they leverage a firm's intangible resources, which may support multiple activities without engendering rivalry for their use. However, numerous complementary resources may also be needed to exploit a firm's intangibles. If these resources are in limited supply, or if it takes time to acquire and assimilate additional resource capacity, then new products may impose costs on existing products by cannibalizing the services of firm resources. Our analysis of product introductions within the pharmaceutical industry provides evidence of resource cannibalization and suggests that product market experience helps offset some of these costs.
Building a university IT community: strength through collaboration and partnerships

What can universities do to create an IT community that can share expertise, insight and creativity? Often, it is the IT divisions themselves that bridge the gaps, providing the conduit for communication, the tools to facilitate collaboration and initiate partnerships. NC State University's Information Technology Division (ITD) has undertaken several projects that provide the framework to facilitate collaboration. In this paper, we will focus on the recent partnerships and collaborations which ITD has found to be most rewarding and those with prospects yet to be fully realized. These partnerships, with academic units and student service organizations alike, bring opportunities to promote learning in a technology rich environment while providing the framework for true collaboration.
Use of a light beam to probe the cell surface in vitro

Abstract An optical nondestructuve microprobe technique is proposed to examine cell surfaces in vitro. Use is made of the phenomenon of total internal reflection to achieve spatially restricted interaction between a light beam and the peripheral zone of a substrate-adherent population of cells. With the help of a suitable optical model, the technique can provide fundamental information on the molecular organization of the cell membrane from measurements made on living cells. Variations of both the intensity and polarization ellipse of the reflected beam carry information about changes in the cell surface that can be induced by any stimulus to which the cells are subjected. This promises to have important applications such as the detection of normal-to-malignant cell transformations.
The rationale for nonsteroidal anti-inflammatory drug therapy for inflammatory myofibroblastic tumors: a Children's Oncology Group study.

Abstract Background Inflammatory myofibroblastic tumors (IMTs) are neoplasms that are highly vascularized, have an intermediate prognosis, and are associated with infiltration, obstruction, local recurrence, and rare metastasis. Resection of large IMTs can lead to substantial morbidity and even mortality. Anecdotal experience suggests that nonsteroidal anti-inflammatory drugs may eradicate large IMTs or shrink them to a more readily resectable size and configuration. To support the hypothesis that nonsteroidal anti-inflammatory drugs are antiangiogenic for IMTs by interfering with vascular endothelial growth factor (VEGF) signaling via cyclooxygenase 2 (COX-2) inhibition, IMT specimens were immunohistochemically examined for expression of COX-2 enzyme and VEGF. Methods The diagnosis of IMT was confirmed in all 18 cases comprising the study. Intensity of COX-2 and VEGF staining was graded, and staining uniformity was examined. ALK-1 protein expression, found in up to two thirds of IMTs, was also determined. Results COX-2 and VEGF expression were identified in all tissue examined, with staining intensity varying independently. ALK-1 protein expression was identified in 33% of specimens. Its presence was not related to the intensity of COX-2 or VEGF staining. Conclusions Our data suggest that the mediators of angiogenesis, VEGF and COX-2, are present and may play an important role in the growth of IMTs.
The vibrational spectrum of 1,1-dicyanocyclopropane

Abstract The infrared spectrum of both vapor and liquid phase samples and the Raman spectrum of a liquid sample of 1,1-dicyano cyclo propane have been obtained. From the infrared vapor phase band contours, the Raman spectrum and polarization data, and group frequency assignments for similar molecules, assignments for all of the fundamental vibrations are proposed except for two which belong in the a 2 species.
INHIBITION OF CEREBELLAR DENDRITE DEVELOPMENT IN NEONATAL THYROID DEFICIENCY

Inhibition of cerebellar dendrite development in neonatal thyroid deficiency Thyroid hormone deficiency was induced in neonatal rats by propylthiouracil. Serum thyroxine levels were assayed and thyroid tissue was examined to assess the clinical condition. At 8, 14, 20, 30 and 42 days after birth, age-matched controls and hypothyroid animals were killed by perfusion. Nissl stains, Golgi preparations, and electron microscopy were done on the cortex of Lobules IX and X of the developing cerebellum. Measurements of the molecular layer revealed that at 8 days, controls are slightly but significantly wider, but at 20 days the difference is much greater and remains so even at 42 days. Golgi studies show deceleration and distortion of development of the Purkinje cell dendritic tree in the abnormal rats. Spine counts of the spiny branchlets on these dendrites show the same incidence per linear micrometer as the age-matched controls, but linear measurements of the branchlets show that the deficient animals have shorter branchlets and regions where spines are absent. Electron microscopy shows that if a spine does develop, it appears similar in control and hypothyroid animals at comparable ages. The effect of the abnormal Purkinje cell dendritic arborization on synaptogenesis in the molecular layer is discussed.
The study to enhance the mask global CD uniformity by removing local CD variation

As pattern size is shrinking, required mask CD specification is tighter and its effect on wafer patterning is more severe. Recent study showed that the effect of mask local CD variation of mask on wafer is much smaller than that of global CD variation.[1] To enhance the device performance, wafer CD uniformity should be enhanced and controlled by mask global CD uniformity. Mask global CD uniformity usually can be enhanced by mask process and optimal fogging effect correction. To enhance the mask global CD uniformity on mask, resist process and FEC (Fogging Effect Correction), reliable CD measurement tool and methods are necessary. Recently, group CD using OCD(Spectroscopic Ellipsometer) or AIMS(Aerial Image Measurement and Simulation) or polynomial fitting method is introduced to represent global CD variation on mask.[2][3][4] These methods are removing local CD variation on mask. The local CD variation will be remained as residual CD after approximation. In this paper, local CD variation of mask and wafer is evaluated and 2 kinds of methods are used to measure CD on mask and wafer, and the correlation of global CD of mask and field CD of wafer are evaluated. And the repeatability of field to field CD uniformity of wafer is evaluated to correct the fields CD uniformity of wafer by controlling the selective changing of transmittance of mask or to feed back to mask process. Higher correlation between fields of wafer, more accurate correction can be possible.
Physical mapping of the genes for three components of the mouse DNA replication complex: Polymerase α to the X chromosome, primase p49 subunit to chromosome 10, and primase p58 subunit to chromosome 1

Abstract DNA polymerase α and primase are two key enzymatic components of the eukaryotic DNA replication complex. In situ hybridization of cloned cDNAs for mouse DNA polymerase α and for the two subunits of mouse primase has been utilized to physically map these genes in the mouse genome. The DNA polymerase α gene (Pola) was mapped to the mouse X chromosome in region C-D. The gene encoding the p58 subunit of primase (Prim2) was located to mouse chromosome 1 in region A5-B and the p49 subunit gene (Prim1) was found to be on mouse chromosome 10 in the distal part of band D that is close to the telomere. Current knowledge of mouse and human conserved chromosomal regions along with the findings presented here lead to predictions of where the genes for the DNA primase subunits may be found in the human genome: the p58 subunit gene may be on human chromosome 2 and the p49 subunit gene on human chromosome 12. The mapping of Pola to region C-D of the mouse X chromosome adds a new marker in a conserved region between the mouse X chromosome and region Xp21–22.1 of the human X chromosome.
Management of the left hepatic duct during extended right hepatectomy

Extended right hepatic lobectomy involves the resection of segments IV to VIII and often includes resection of the caudate lobe (segment I). This resection is necessary to treat right-sided tumours that extend into segment IV. On occasion these tumours will extend to the umbilical fissure (Figure 1) and involve the left hepatic duct at the base of the fissure. This involvement has often been considered a contraindication to resection as mobilisation of tumour off the left duct is technically difficult and may result in a positive margin. Unrecognised damage to the duct may also present in the postoperative period with a biliary fistula. We report three patients who presented with massive right-sided tumours involving the left hepatic duct at the base of the umbilical fissure, on whom extended right hepatectomy was carried out in conjunction with resection and primary anastomosis of the left duct. Open in a separate window Figure 1. Line drawing illustrating a tumour lying in the base of segment IV.
Evoked cortical potentials and discrimination problem-solving in humans☆

Abstract Evoked cortical potentials to stimuli in a problem-solving task were measured at the vertex and occipital lobe to determine if there were systematic changes in cortical activity associated with hypothesis-testing behavior. The learning task consisted of the subjects responding to and eliminating hypothesized stimuli until only the correct one remained. A modified blank-trials procedure was used to determine the subjects' hypotheses and to permit averaging of visual evoked responses (VERs). It was shown that the solution of the problems and the hypotheses tested in reaching solution may be inferred from changes in two measures of vertex cortical activity: a late positive component of the VER with a latency of approximately 300 msec and by a slow positive shift in baseline for at least 400 msec following the stimulus hypothesized as correct. These measures were enhanced in response to a given stimulus when hypothesized and responded to. When changes in these measures were considered as a function of the number of feedback trials, their amplitude was correlated with the behavioral measure of problem-solution. Although this relationship was statistically significant only when subjects were giving a reaction time response to the hypothesized stimulus, it was concluded that the problem-solving effect on vertex activity could not be attributed completely to motor processes.
Stabilities of adsorption sites and charge transfers at the K/Si(001) surface.

Various adsorption models of a K atom on the Si(001) surface including the top-site model, and the charge transfer between K and Si have been exhaustively investigated using accurate ab initio self-consistent unrestricted Hartree-Fock total-energy calculations with the Hay-Wadt effective core potentials. Several cluster models of bare and hydrogen-bonded silicon atoms used to simulate the different possible adsorption sites on the Si(001) surface have been examined. The structural relaxation of the substrate on adsorption of K atoms has been accounted for by optimizing all the atomic positions of the adsorbed and substrate atoms. Also, the effects of electron correlation have been included by invoking the concepts of fourth-order many-body perturbation theory and these are found to be crucial in determining the preferred adsorption sites. Population analyses up to the many-body perturbation theory at the second level of all the models studied consistently show that the charge transferred from the K atom to Si lies between 0.12e and 0.40e. This charge transfer combined with the values of the K-Si bond lengths obtained in our calculations tend to suggest a polarized covalent bonding for the K/Si(001) system.
Pediatric Specialists' Beliefs About Gastroesophageal Reflux Disease in Premature Infants

BACKGROUND: Wide variation exists in the treatment of suspected gastroesophageal reflux disease (GERD) in premature infants; it is unknown to what degree diagnosis and treatment are affected by the treating physician9s medical specialty or interpretation of the medical literature. METHODS: This study involved an online survey of board-certified neonatologists, pediatric pulmonologists, and pediatric gastroenterologists about their beliefs regarding the symptoms, diagnosis, and treatment of GERD in premature infants in the NICU on the basis of both clinical impression and interpretation of the literature. RESULTS: A total of 1021 neonatologists, 232 pediatric pulmonologists, and 222 pediatric gastroenterologists participated in the study (47.5% response rate). There was disagreement among specialists in nearly all aspects of the survey. Pulmonologists were most likely to report that respiratory symptoms are caused by GERD (P 50% of respondents supporting its effectiveness. There was moderate correlation between physician belief based on the medical literature and belief based on clinical impression (Spearman rank correlation: 0.47–0.75). For therapies supported by multiple meta-analyses in infants versus therapies with few infant trials, physicians rated the evidence for effectiveness similarly. CONCLUSIONS: There is wide variation among pediatric specialists regarding beliefs about GERD in premature infants, as well as about the weight of evidence in the medical literature for this patient population. Physician beliefs do not seem to be driven by the degree of evidence in the neonatal literature. With no agreed-on standard of care in the setting of widespread use of antireflux medications, greater understanding is needed about the ways physicians form clinical impressions, access and process medical evidence, and apply it to patient care.
Cdkn2a encodes functional variation of p16INK4a but not p14ARF, which confers selection in mouse lung tumorigenesis

The cyclin-dependent kinase inhibitor 2a (Cdkn2a) locus encodes two distinct tumor suppressors, p16INK4a and p19ARF, whose functions interrelate in the regulation of cell proliferation as key components of the retinoblastoma and p53 pathways, respectively. In many types of cancer, alterations of Cdkn2a abrogate the functions of both suppressors, implying that both are integral to the genesis of certain cancer types. While this has been observed in mouse lung adenocarcinogenesis, recent observations also suggested that naturally occurring variation at the Cdkn2a locus is probably operative in the development of these tumors. Firstly, two common haplotypes of mouse Cdkn2a have been identified, each of which encodes cosegregating variants of p16INK4a and p19ARF. The p16INK4a variants differ at amino acids 18 (histidine or proline) and 51 (valine or isoleucine), whereas the p19ARF variants differ only at amino acid 72 (histidine or arginine). Secondly, genetic resistance to lung tumor formation appears to segregate with one particular haplotype, which also is deleted preferentially in lung adenocarcinomas of Cdkn2a heterozygous mice. Here we attempt to explain these observations and to characterize further the roles of p16INK4a and p19ARF in mouse lung tumorigenesis by examining the function and expression of each of the variants of Cdkn2a. Functional analysis showed that the proline 18/isoleucine 51 p16INK4a variant was diminished in cdk6 binding, cdk6 inhibition and NIH/3T3 fibroblast growth suppression compared with the histidine 18/valine 51 variant, whereas both of the p19ARF variants suppressed growth with similar potencies. Also, the different alleles for p16INK4a and p19ARF were transcribed equally in the normal lungs of Cdkn2a heterozygotes, as determined by comparative reverse transcription–polymerase chain reaction–single-stranded conformation polymorphism analysis. These results indicate that strain-specific variation in p16INK4a function is exploited in mouse lung tumorigenesis and strongly implicate a role for p16INK4a in lung cancer predisposition and development. Mol. Carcinog. 25:92–98, 1999. © 1999 Wiley-Liss, Inc.
The pursuit of useable knowledge in instructional technology

The object of inquiry in instructional technology is not simply knowledge, but useable knowledge. This paper explores the dimensions of relevance with respect to research and suggests ways the research community can accommodate the needs and interests of practicing professionals in the field. Research relevance is examined as a reflection of: (a) practitioner and disciplinary values; (b) perceived credibility, viewed in terms of authenticity, methods employed, and replicability; and (c) perceptions of utility based upon the concrete nature of the findings. Specific recommendations relate to expanding the range of topics addressed in our research, expanding the range of research methods employed, orienting our research communication to specific practitioner communities, conducting research under natural conditions, replicating research, and establishing links between abstract and concrete findings. Finally, the role of the practitioner as an educated consumer of research is discussed.
Relativistic channel-coupling effect in the deuteron matter radius

Abstract Local square-well and nonlocal separable potentials are used in the Dirac equation to show that the dominant relativistic effect in the deuteron matter radius r m comes from the coupling to the lower Dirac component in essentially the same way as the coupling to the D-state and higher-mass states in the Schrodinger equation. The resulting relativistic correction to r m turns out to be sensitive to dynamics. In the limit of weak binding, it gives a result in good agreement with the traditional kinematical approach for both local and nonlocal potentials.
Checklist of Marine Biota of China Seas

This hefty volume is faithful to its title—a Check List. It systematically records the Chinese marine biota (prokaryotes and eukaryotes) as currently understood and provides the scientific names in both Latin and Chinese, including original designation, the main synonyms (in square brackets), and the geographical distributions in China seas and the world oceans of all species. It covers some 22,629 taxa in 46 major phyla. This volume supercedes an earlier volume (Huang, 1994) and includes a 30% increase over the fauna recorded 16 years ago. This treatment entailed input from over 50 experts. The book is provided with an excellent systematic index of all taxa. The marine arthropod sections alone encompass material on pages 606-812. While the bulk of the introductory material is in Chinese, the closely paired Chinese/English entries in the main checklist are helpful, allowing those in the West, and so inclined, to link Chinese names with the Latin binomens. Thus, this book can serve as a valuable addition to any systematic library.
Effects of Environmental Factors and Nutrient Availability on the Biochemical Composition of Algae for Biofuels Production: A Review

Due to significant lipid and carbohydrate production as well as other useful properties such as high production of useful biomolecular substrates (e.g., lipids) and the ability to grow using non-potable water sources, algae are being explored as a potential high-yield feedstock for biofuels production. In both natural and engineered systems, algae can be exposed to a variety of environmental conditions that affect growth rate and cellular composition. With respect to the latter, the amount of carbon fixed in lipids and carbohydrates (e.g., starch) is highly influenced by environmental factors and nutrient availability. Understanding synergistic interactions between multiple environmental variables and nutritional factors is required to develop sustainable high productivity bioalgae systems, which are essential for commercial biofuel production. This article reviews the effects of environmental factors (i.e., temperature, light and pH) and nutrient availability (e.g., carbon, nitrogen, phosphorus, potassium, and trace metals) as well as cross-interactions on the biochemical composition of algae with a special focus on carbon fixation and partitioning of carbon from a biofuels perspective.
Aerial distribution, temperature-dependent seasonal variation, and sources of polycyclic aromatic hydrocarbons in pine needles from the Houston metropolitan area, Texas, USA.

To investigate the aerial distribution, seasonal variation, and sources of polycyclic aromatic hydrocarbons (PAHs), pine needles were collected from 18 sites in the Houston metropolitan area, Texas, USA. Total PAHs ranged from 209 to 2,226 ng/g (dry wt.), which were similar to those found in other urban areas. The highest and lowest concentrations were found in samples from the inner city of Houston and the outer edge of suburban area, respectively. Aerial distribution of PAHs in pine needles was closely correlated to the proximity to densely occupied residential area and traffic volumes around sampling sites. Seasonal changes of PAHs in pine needles were inversely correlated with ambient temperature with lower levels in warmer months. Calculated concentrations of 3-ring PAHs in the air had a positive correlation with ambient temperature with higher levels in warmer months. Ratios of PAHs in pine needles to PAHs in the air decreased as ambient temperature increased because fugacity (escaping tendency) of ...
A highly efficient SiGe differential power amplifier using an envelope-tracking technique for 3GPP LTE applications

This paper presents a highly-efficient polar transmitter (TX) system that adopts the envelope-tacking (ET) technique with a differential SiGe power amplifier (PA) for 3GPP Long Term Evolution (LTE) applications. The differential PA was designed using a cascode topology, reaching power-added efficiency (PAE) of 50% at output power of 22dBm in continuous wave (CW) mode. The experimental data also shows that the proposed ET-based polar TX system with the cascode PA delivers 21dBm average output power with 33.6% PAE at 1.42 GHz, while also meeting the LTE 16QAM linearity specs for both error vector magnitude (EVM) and TX emission mask without the need of PA predistortion.
A note on initial-value formulations of elliptic boundary-value problems

An elliptic boundary-value problem may be formulated as an initial-value problem by approximating it as a two-point boundary-value problem. A method proposed in [6] not requiring this approximation is disproved by means of an example.
Endoscopic Findings in Sleep Apnea Associated with Acromegaly

Two acromegalic patients presented with the additional complaint of excessive daytime sleepiness. Subsequent sleep laboratory evaluation revealed that each patient had concurrent obstructive sleep apnea. In each patient, endoscopic examination of the upper airway revealed that on inspiration, the soft tissue of the posterior and lateral hypopharynx invaginated into the laryngeal vestibule before any posterior movement of the tongue. Neither enlargement of the tongue nor in movement in relation to respiration appeared to be the primary factors in the etiology of the upper airway obstruction. After tracheostomy, both the obstructive sleep apnea and excessive daytime sleepiness were eliminated. Our case reports indicate that the treatment and prognosis of patients with acromegaly are affected when sleep apnea is concurrently diagnosed. When a patient is suspected of being acromegalic and also complains of excessive daytime sleepiness, obtaining a through sleep history from the patient as well as from the bed partner is essential. If sleep apnea is then diagnosed, a tracheostomy should be considered an initial and continuing part of the overall treatment plan.
AB INITIO CALCULATION OF THERMODYNAMIC PROPERTIES OF SILICON

We present a fully ab initio calculation of the thermodynamic properties for silicon within the quasiharmonic approximation, making use of volume-dependent phonon frequencies obtained from pseudopotential local-density calculations. The temperature dependence of the thermal-expansion coefficient, specific heat (at constant volume), and other related quantities are studied. We confirm that the thermal-expansion coefficient behaves differently in three temperature regions: positive for temperature below 15 K, negative between 15 and 125 K, and positive again above 125 K. This finding agrees with experiment. The abnormal (negative) thermal-expansion coefficient at low temperatures is explained through a detailed study of mode Gr\"uneisen parameters. Both specific-heat and thermal-expansion-coefficient values calculated are in excellent agreement with experiment up to a few hundred kelvin.
Effects of a beaver pond on runoff processes: comparison of two headwater catchments

Abstract Natural variations in concentrations of 18 O, D, and H 4 SiO 4 in two tributary catchments of Woods Lake in the west-central Adirondack Mountains of New York were measured during 1989–1991 to examine runoff processes and their implications for the neutralization of acidic precipitation by calcium carbonate treatment. The two catchments are similar except that one contained a 1.3 ha beaver pond. Evaporation from the beaver pond caused a seasonal decrease in the slope of the meteoric water line in stream water from the catchment with a beaver pond (WO2). No corresponding change in slope of the meteoric water line was evident in stream water from the other catchment (WO4), nor in ground water nor soil water from either catchment, indicating that evaporative fractionation was not significant. Application of a best-fit sine curve to δ 18 O data indicated that base flow in both catchments had a residence time of about 100 days. Ground water from a well finished in thick till had the longest residence time (160 days); soil water from the O-horizon and B-horizon had residence times of 63 and 80 days, respectively. Water previously stored within each catchment (pre-event water) was the predominant component of streamflow during spring snowmelt and during spring and autumn rainfall events, but the proportion of streamflow that consisted of pre-event water differed significantly in the two catchments. The proportion of event water (rain and snowmelt) in WO2 was smaller than at WO4 early in the spring snowmelt of March 13–17, 1990, but the proportions of source water components for the two catchments were almost indistinguishable by the peak flow on the third day of the melt. The event water was further separated into surface-water and subsurface-water components by utilizing measured changes in H 4 SiO 4 concentrations in stream water during the snowmelt. Results indicated that subsurface flow was the dominant pathway by which event water reached the stream except during the peak flow of a rain-on-snow event on the last day of the melt. Streamflow from a spring rain storm with dry antecendent conditions two months later (May 16–18, 1990), was less than 5% event water at peak flow in WO2 and 26% in WO4. This change from the runoff pattern in March is attributed to retention of event water in the beaver pond favored by relatively low pre-event storage and isothermal (nonstratified) conditions in the pond that allowed mixing. Streamflow during several autumn storms was about 15–25% event water at peak flow in WO4; the highest values for event water were associated with wet antecedent moisture conditions. These results indicate that a beaver pond can significantly affect the downstream delivery of event water through evaporation and mixing, but provides minimal retention during large runoff events such as snowmelt. Beaver ponds are expected to provide greater opportunity for neutralization of acidic waters during most of the year in catchments treated with calcium carbonate, but little neutralization effect during snowmelt.