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Terms modified by Midpoint Selected AbstractsNaturally Occurring Female Hairline PatternsDERMATOLOGIC SURGERY, Issue 6 2009BERNARD P. NUSBAUM MD BACKGROUND Hair transplantation is gaining popularity in women. Although much has been written about hairline design in male patients, more information is needed about natural female hairlines. OBJECTIVE To determine the frequency, dimensions, and location of structures that compose the female hairline. METHODS Hairline characteristics were measured in 360 female volunteers at an informal hair salon setting. RESULTS A widow's peak was present in 81%. The mean distance from the mid-eyebrow to the frontal midpoint was 5.5 cm. Lateral mounds were observed in 98%. The mean distance from the frontal midpoint to the apex of the lateral mounds was 3.74 cm on the right and 3.97 cm on the left. The mean distance from the apex of the lateral mounds to the apex of the temporal points was 3.78 cm on the right and 3.51 cm on the left. The shape of the temporal recessions was concave triangular or concave oval in 87% of the subjects. CONCLUSION This study provides proposed guidelines for designing the hairline in women. [source] Voltammetric Antioxidant Analysis in Mineral Oil Samples Immobilized into Boron-Doped Diamond Micropore Array ElectrodesELECTROANALYSIS, Issue 12 2009Xiaohang Zhang Abstract Mineral oil microdroplets containing the model antioxidant N,N -didodecyl- N,,N, -diethyl-phenylene-diamine (DDPD) are immobilized into a 100×100 pore-array (ca. 10,,m individual pore diameter, 100,,m pitch) in a boron-doped diamond electrode surface. The robust diamond surface allows pore filling, cleaning, and reuse without damage to the electrode surface. The electrode is immersed into aqueous electrolyte media, and voltammetric responses for the oxidation of DDPD are obtained. In order to further improve the current responses, 20,wt% of carbon nanofibers are co-deposited with the oil into the pore array. Voltammetric signals are consistent with the oxidation of DDPD and the associated transfer of perchlorate anions (in aqueous 0.1,M NaClO4) or the transfer of protons (in aqueous 0.1,M HClO4). From the magnitude of the current response, the DDPD content in the mineral oil can be determined down to less than 1,wt% levels. Perhaps surprisingly, the reversible (or midpoint) potential for the DDPD oxidation in mineral oil (when immersed in 0.1 NaClO4) is shown to be concentration-dependent and to shift to more positive potential values for more dilute DDPD in mineral oil solutions. An extraction mechanism and the formation of a separate organic product phase are proposed to explain this behavior. [source] Rat anterodorsal thalamic head direction neurons depend upon dynamic visual signals to select anchoring landmark cuesEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 2 2004Michaël B. Zugaro Abstract Head direction cells, which are functionally coupled to ,place' cells of the hippocampus, a structure critically involved in spatial cognition, are likely neural substrates for the sense of direction. Here we studied the mechanism by which head direction cells are principally anchored to background visual cues [M.B. Zugaro et al. (2001) J. Neurosci., 21, RC154,1,5]. Anterodorsal thalamic head direction cells were recorded while the rat foraged on a small elevated platform in a 3-m diameter cylindrical enclosure. A large card was placed in the background, near the curtain, and a smaller card was placed in the foreground, near the platform. The cards were identically marked, proportionally dimensioned, subtended the same visual angles from the central vantage point and separated by 90°. The rat was then disoriented in darkness, the cards were rotated by 90° in opposite directions about the center and the rat was returned. Preferred directions followed either the background card, foreground card or midpoint between the two cards. In continuous lighting, preferred directions shifted to follow the background cue in most cases (30 of the 53 experiments, Batschelet V -test, P < 0.01). Stroboscopic illumination, which perturbs dynamic visual signals (e.g. motion parallax), blocked this selectivity. Head direction cells remained equally anchored to the background card, foreground card or configuration of the two cards (Watson test, P > 0.1). This shows that dynamic visual signals are critical in distinguishing typically more stable background cues which govern spatial neuronal responses and orientation behaviors. [source] High thermal and chemical stability of Thermus thermophilus seven-iron ferredoxinFEBS JOURNAL, Issue 23 2003Linear clusters form at high pH on polypeptide unfolding To probe the stability of the seven-iron ferredoxin from Thermus thermophilus (FdTt), we investigated its chemical and thermal denaturation processes in solution. As predicted from the crystal structure, FdTt is extremely resistant to perturbation. The guanidine hydrochloride-induced unfolding transition shows a midpoint at 6.5 m (pH 7, 20 °C), and the thermal midpoint is above boiling, at 114 °C. The stability of FdTt is much lower at acidic pH, suggesting that electrostatic interactions are important for the high stability at higher pH. On FdTt unfolding at alkaline pH, new absorption bands at 520 nm and 610 nm appear transiently, resulting from rearrangement of the cubic clusters into linear three-iron species. A range of iron,sulfur proteins has been found to accommodate these novel clusters in vitro, although no biological function has yet been assigned. [source] Morphometric Analysis on the Size, Shape and Areal Distribution of Glacial Cirques in the Maritime Alps (Western French-Italian Alps)GEOGRAFISKA ANNALER SERIES A: PHYSICAL GEOGRAPHY, Issue 3 2004Paolo Roberto Federici Abstract The morphometry of 432 glacial cirques in the Maritime Alps (Western French-Italian Alps), studied over several years of fieldwork, was analysed with the use of a geographical information system. Some of the parameters automatically evaluated from digital elevation models required an objective and relatively new definition. In particular, cirque length was measured along a line that, from the threshold midpoint, splits the cirque into two equivalent surfaces; cirque width was automatically drawn as the longest line inscribed in the cirque and perpendicular to the length line. Significant correlations were found among the different factors and parameters analysed. In particular, cirque shape analysis showed that cirques develop allometrically in the three dimensions, i.e. more in length and width than in altitudinal range. Nevertheless cirques of the Maritime Alps have a regular, almost circular shape (mean L/W value = 1.07). The correlations among length, width and area are all very high (r2= 0.8,0.9). In terms of size, cirques show a wide range in area from 0.06 to 5.2 km2 with a mean value of 0.4 km2. The largest cirques are found on SSW-facing slopes and at high elevations. Small cirques can be found at all altitudes but all those at high elevation are part of compound cirques at the main head valleys. Most cirques (37%) are characterized by a northern aspect; NE and SW are also frequent directions. [source] Required source distribution for interferometry of waves and diffusive fieldsGEOPHYSICAL JOURNAL INTERNATIONAL, Issue 2 2009Yuanzhong Fan SUMMARY The Green's function that describes wave propagation between two receivers can be reconstructed by cross-correlation provided that the receivers are surrounded by sources on a closed surface. This technique is referred to as ,interferometry' in exploration seismology. The same technique for Green's function extraction can be applied to the solution of the diffusion equation if there are sources throughout in the volume. In practice, we have only a finite number of active sources. The issues of the required source distribution is investigated, as is the feasibility of reconstructing the Green's function of the diffusion equation using a limited number of sources within a finite volume. We study these questions for homogeneous and heterogeneous media for wave propagation and homogeneous media for diffusion using numerical simulations. These simulations show that for the used model, the angular distribution of sources is critical in wave problems in homogeneous media. In heterogeneous media, the position and size of the heterogeneous area with respect to the sources determine the required source distribution. For diffusion, the sensitivity to the sources decays from the midpoint between the two receivers. The required width of the source distribution decreases with frequency, with the result that the required source distribution for early- and late-time reconstruction is different. The derived source distribution criterion for diffusion suggests that the cross-correlation-based interferometry is difficult to apply in field condition. [source] Effect of reline material and denture base surface treatment on the impact strength of a denture base acrylic resinGERODONTOLOGY, Issue 1 2010Luciano Elias Da Cruz Perez doi:10.1111/j.1741-2358.2009.00292.x Effect of reline material and denture base surface treatment on the impact strength of a denture base acrylic resin Objective:, In this study, the effect of relining and surface treatment on the impact strength (IS) of a heat-polymerising denture base acrylic resin (Lucitone 550-L) was evaluated. Materials and methods:, Rectangular bars of L were made (60 × 6 × 2 mm) and relined (2 mm) with the relining resins Ufi Gel Hard (UH) and Tokuso Rebase Fast (TR). Specimens relined with L and intact L, TR and UH specimens were also made (60 × 6 × 4 mm), for comparison. Before relining, the L surface was left untreated or wetted with methyl methacrylate monomer and/or the bonding agents (BA) supplied by manufacturers of the reline resins. V-notches were machined at the midpoint of the length of all specimens. The notches were made either across the width (Nw) or across the thickness of the specimens (Nth). The Charpy impact test was performed using a 0.5-J pendulum, which had been specially designed and constructed. Data were analysed separately for each notch position using one-way analysis of variance and Tukey honestly significant difference post - hoc test (p = 0.05). Results:, The IS of L was similar to that of L/L. For the Nw notch, treating the denture base L with TR BA and relining with TR reline material produced the highest IS. Conclusion:, The IS of specimens made from heat polymerising acrylic resin Lucitone 550 was increased after relining using the hard chairside reline resin TR with its proprietary BA. [source] Analysis of a Vertical Dipole Tracer Test in Highly Fractured RockGROUND WATER, Issue 5 2002William E. Sanford The results of a vertical dipole tracer experiment performed in highly fractured rocks of the Clare Valley, South Australia, are presented. The injection and withdrawal piezometers were both screened over 3 m and were separated by 6 m (midpoint to midpoint). Due to the long screen length, several fracture sets were intersected, some of which do not connect the two piezometers. Dissolved helium and bromide were injected into the dipole flow field for 75 minutes, followed by an additional 510 minutes of flushing. The breakthrough of helium was retarded relative to bromide, as was expected due to the greater aqueous diffusion coefficient of helium. Also, only 25% of the total mass injected of both tracers was recovered. Modeling of the tracer transport was accomplished using an analytical one-dimensional flow and transport model for flow through a fracture with diffusion into the matrix. The assumptions made include: streamlines connecting the injection and withdrawal point can be modeled as a dipole of equal strength, flow along each streamline is one dimensional, and there is a constant Peclet number for each streamline. In contrast to many other field tracer studies performed in fractured rock, the actual travel length between piezometers was not known. Modeling was accomplished by fitting the characteristics of the tracer breakthrough curves (BTCs), such as arrival times of the peak concentration and the center of mass. The important steps were to determine the fracture aperture (240 ,m) based on the parameters that influence the rate of matrix diffusion (this controls the arrival time of the peak concentration); estimating the travel distance (11 m) by fitting the time of arrival of the centers of mass of the tracers; and estimating fracture dispersivity (0.5 m) by fitting the times that the inflection points occurred on the front and back limbs of the BTCs. This method works even though there was dilution in the withdrawal well, the amount of which can be estimated by determining the value that the modeled concentrations need to be reduced to fit the data (,50%). The use of two tracers with different diffusion coefficients was not necessary, but it provides important checks in the modeling process because the apparent retardation between the two tracers is evidence of matrix diffusion and the BTCs of both tracers need to be accurately modeled by the best fit parameters. [source] Assessment of patient satisfaction with pharmaceutical services in a Nigerian teaching hospitalINTERNATIONAL JOURNAL OF PHARMACY PRACTICE, Issue 1 2004Azuka C. Oparah lecturer ABSTRACT Objective To assess patients' satisfaction with pharmaceutical services using an"ideal referent" model, and to further explore the validity of an existing patient satisfaction instrument. Method A cross-sectional survey was conducted with a sample of 500 outpatients recruited consecutively at the University of Benin teaching hospital, Nigeria. A self-completion questionnaire that employed a Likert-type scale was used. Data were used to calculate scores on a scale that ranged from 20 to 100, with an assumed midpoint of 60. Descriptive statistics on the sample characteristics and questionnaire items were computed including means, standard deviations and frequency distributions. Varimax rotation with Kaiser normalisation was employed in principal factor analysis. Student's t -test and one-way ANOVA were used for inferential statistics. Key findings The instrument reliability was determined to be 0.9641 and was comparable to the reference study. Nearly half of the patients (46%) rated the amount of time the pharmacist offered to spend with them as poor. About one-third rated promptness of prescription service as poor. Only 49% felt satisfied with the pharmaceutical services. Overall, pharmacy services received a satisfaction rating of 56.04±24.49, below the midpoint. Perceived satisfaction was significantly higher in "friendly explanation" than in "managing therapy" (t=3.916; P<0.0001). Conclusion The study provides evidence that patients experience low satisfaction with current pharmaceutical services at the study hospital. The sociodemographic characteristics of patients were not associated with their level of satisfaction. We further confirm the validity of the patient satisfaction questionnaire in a Nigerian practice setting. [source] Resistance and Agility Training Reduce Fall Risk in Women Aged 75 to 85 with Low Bone Mass: A 6-Month Randomized, Controlled Trial,JOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 5 2004Teresa Liu-Ambrose PhD Objectives: To compare the effectiveness of group resistance and agility-training programs in reducing fall risk in community-dwelling older women with low bone mass. Design: A randomized, controlled, single-blind 25-week prospective study with assessments at baseline, midpoint, and trial completion. Setting: Community center. Participants: Community-dwelling women aged 75 to 85 with low bone mass. Intervention: Participants were randomly assigned to one of three groups: resistance training (n=32), agility training (n=34), and stretching (sham) exercises (n=32). The exercise classes for each study arm were held twice weekly. Measurements: The primary outcome measure was fall risk (derived from weighted scores from tests of postural sway, reaction time, strength, proprioception, and vision), as measured using a Physiological Profile Assessment (PPA). Secondary outcome measures were ankle dorsiflexion strength, foot reaction time, and Community Balance and Mobility Scale score. Results: Attendance at the exercise sessions for all three groups was excellent: resistance training (85.4%), agility training (87.3%), and stretching program (78.8%). At the end of the trial, PPA fall-risk scores were reduced by 57.3% and 47.5% in the resistance and agility-training groups, respectively, but by only 20.2% in the stretching group. In the resistance and agility groups, the reduction in fall risk was mediated primarily by improved postural stability, where sway was reduced by 30.6% and 29.2%, respectively. There were no significant differences between the groups for the secondary outcomes measures. Within the resistance-training group, reductions in sway were significantly associated with improved strength, as assessed using increased squat load used in the exercise sessions. Conclusion: These findings support the implementation of community-based resistance and agility-training programs to reduce fall risk in older women with low bone mass. Such programs may have particular public health benefits because it has been shown that this group is at increased risk of falling and sustaining fall-related fractures. [source] Nursing Home Facility Risk Factors for Infection and Hospitalization: Importance of Registered Nurse Turnover, Administration, and Social FactorsJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 12 2002Sheryl Zimmerman PhD OBJECTIVES: Determine the relationship between a broad array of structure and process elements of nursing home care and (a) resident infection and (b) hospitalization for infection. DESIGN: Baseline data were collected from September 1992 through March 1995, and residents were followed for 2 years; facility data were collected at the midpoint of follow-up. SETTING: A stratified random sample of 59 nursing homes across Maryland. PARTICIPANTS: Two thousand fifteen new admissions aged 65 and older. MEASUREMENTS: Facility-level data were collected from interviews with facility administrators, directors of nursing, and activity directors; record abstraction; and direct observation. Main outcome measures included infection (written diagnosis, a course of antibiotic therapy, or radiographic confirmation of pneumonia) and hospitalization for infection (indicated on medical records). RESULTS: The 2-year rate of infection was 1.20 episodes per 100 resident days, and the hospitalization rate for infection was 0.17 admissions per 100 resident days. Except for registered nurse (RN) turnover, which related to both infection and hospitalization, different variables related to each outcome. High rates of incident infection were associated with more Medicare recipients, high levels of physical/occupational therapist staffing, high licensed practical nurse staffing, low nurses' aide staffing, high intensity of medical and therapeutic services, dementia training, staff privacy, and low levels of psychotropic medication use. High rates of hospitalization for infection were associated with for-profit ownership, chain affiliation, poor environmental quality, lack of resident privacy, lack of administrative emphasis on staff satisfaction, and low family/friend visitation rates. Adjustment for resident sex, age, race, education, marital status, number of morbid diagnoses, functional status, and Resource Utilization Group, Version III score did not alter the relationship between the structure and process of care and outcomes. CONCLUSIONS: The association between RN turnover and both outcomes underscores the relationship between nursing leadership and quality of care in these settings. The relationship between hospitalization for infection and for-profit ownership and chain affiliation could reflect policies not to treat acute illnesses in house. The link between social factors of care (environmental quality, prioritizing staff satisfaction, resident privacy, and facility visitation) and hospitalization indicates that a nonmedical model of care may not jeopardize, and may in fact benefit, health-related outcomes. All of these facility characteristics may be modifiable, may affect healthcare costs, and may hold promise for other, less-medical, forms of residential long-term care. [source] Extreme US stock market fluctuations in the wake of 9/11JOURNAL OF APPLIED ECONOMETRICS, Issue 1 2008S. T. M. Straetmans We apply extreme value analysis to US sectoral stock indices in order to assess whether tail risk measures like value-at-risk and extremal linkages were significantly altered by 9/11. We test whether semi-parametric quantile estimates of ,downside risk' and ,upward potential' have increased after 9/11. The same methodology allows one to estimate probabilities of joint booms and busts for pairs of sectoral indices or for a sectoral index and a market portfolio. The latter probabilities measure the sectoral response to macro shocks during periods of financial stress (so-called ,tail-,s'). Taking 9/11 as the sample midpoint we find that tail-,s often increase in a statistically and economically significant way. This might be due to perceived risk of new terrorist attacks. Copyright © 2008 John Wiley & Sons, Ltd. [source] Age Trends in Femur Stresses From a Simulated Fall on the Hip Among Men and Women: Evidence of Homeostatic Adaptation Underlying the Decline in Hip BMDJOURNAL OF BONE AND MINERAL RESEARCH, Issue 9 2006Thomas J Beck ScD Abstract Age trends in proximal femur stresses were evaluated by simulating a fall on the greater trochanter using femur geometry from hip DXA scans of 5334 white men and women in the NHANES III survey. Expansion of femur outer diameter seems to counter net bone loss so that stresses remain similar across age groups, but stresses are higher in older women than in older men. Introduction: The age decline in hip BMD is caused by both bone loss and expansion of outer diameter that increases the region size over which mass is measured in a DXA scan. Because expansion has an opposing effect on structural strength, it may be a homeostatic adaptation to net bone loss to ensure that load stresses are kept within a narrow range. Materials and Methods: Age trends in femur stresses were evaluated with an engineering beam simulation of a fall on the greater trochanter. Hip geometry was extracted from hip DXA scans using the Hip Structure Analysis (HSA) software on 2613 non-Hispanic white men and 2721 women from the third National Health and Nutrition Examination Survey (NHANES III). Using body weight as load, stresses were computed on the inferior-medial and superior-lateral femur neck at its narrowest point and the medial and lateral shaft 2 cm distal to the midpoint of the lesser trochanter. Stresses and the underlying geometries in men and women >50 years oaf age were compared with those 20,49 years of age. Results: Compared with men <50 years of age, stresses in older men were 6% lower on both surfaces of the shaft, 4% lower on the inferior-medial neck, and not different on the superior-lateral neck. In women >50 years of age, stresses on the proximal shaft and inferior-medial neck remained within 3% of young values but were 13% greater on the superior-lateral neck. Neck stresses in young women were lower on the superior-lateral than the inferior-medial neck, but lateral stress increased to the level on the medial surface in older women. Stresses were higher in women than in men, with a greater gender difference in those >50 years of age. Conclusions: We conclude that femur expansion has a homeostatic effect in men and women that opposes bone loss so that stresses change little with age. Because expansion preserves stresses with progressively less bone mass, the process may reduce structural stability in the femoral neck under fall conditions, especially in the elderly female. [source] Quantitative Trait Loci on Chromosomes 2p, 4p, and 13q Influence Bone Mineral Density of the Forearm and Hip in Mexican Americans,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 12 2003Candace M Kammerer Abstract We performed a genome scan using BMD data of the forearm and hip on 664 individuals in 29 Mexican-American families. We obtained evidence for QTL on chromosome 4p, affecting forearm BMD overall, and on chromosomes 2p and 13q, affecting hip BMD in men. Introduction: The San Antonio Family Osteoporosis Study (SAFOS) was designed to identify genes and environmental factors that influence bone mineral density (BMD) using data from large Mexican-American families. Materials and Methods: We performed a genome-wide linkage analysis using 416 highly polymorphic microsatellite markers spaced approximately 9.5 cM apart to locate and identify quantitative trait loci (QTL) that affect BMD of the forearm and hip. Multipoint variance components linkage analyses were done using data on all 664 subjects, as well as two subgroups of 259 men and 261 premenopausal women, from 29 families for which genotypic and phenotypic data were available. Results: We obtained significant evidence for a QTL affecting forearm (radius midpoint) BMD in men and women combined on chromosome 4p near D4S2639 (maximum LOD = 4.33, genomic p = 0.006) and suggestive evidence for a QTL on chromosome 12q near locus D12S2070 (maximum conditional LOD = 2.35). We found suggestive evidence for a QTL influencing trochanter BMD on chromosome 6 (maximum LOD = 2.27), but no evidence for QTL affecting the femoral neck in men and women combined. In men, we obtained evidence for QTL affecting neck and trochanter BMD on chromosomes 2p near D2S1780 (maximum LOD = 3.98, genomic p = 0.013) and 13q near D13S788 (maximum LOD = 3.46, genomic p = 0.039), respectively. We found no evidence for QTL affecting forearm or hip BMD in premenopausal women. Conclusion: These results provide strong evidence that a QTL on chromosome 4p affects radius BMD in Mexican-American men and women, as well as evidence that QTL on chromosomes 2p and 13q affect hip BMD in men. Our results are consistent with some reports in humans and mice. [source] Transabdominal sonography of the normal gastroesophageal junction in childrenJOURNAL OF CLINICAL ULTRASOUND, Issue 6 2001Francesco Esposito MD Abstract Purpose Because sonography identifies abnormalities of the gastroesophageal junction, it is essential to understand the normal sonographic anatomy. The aim of this study was to determine the normal sonographic appearance of the gastroesophageal junction and its variations and to provide measurements of the abdominal esophagus in asymptomatic, healthy children. Methods In this prospective study, 124 healthy children (75 boys and 49 girls), aged 2 days,12 years, underwent abdominal sonography. With the patient in a supine position, the transducer was placed under the xiphoid and the ultrasound beam was directed cephalad through the window of the left lobe of the liver. The length of the abdominal esophagus was measured from the point at which it penetrated the diaphragm to the gastroesophageal junction. The thickness was measured on the anterior wall at the midpoint of the abdominal esophagus. Results The gastroesophageal junction was identified by sonography in all of the children. The mean length of the abdominal portion of the esophagus ranged from 18 mm in the newborns to 34 mm in children older than 6 years. The wall thickness ranged from 2.4 mm to 5.7 mm. Conclusions Our results indicate that visualization of the gastroesophageal junction and measurement of the abdominal esophagus are readily achievable with real-time sonography in healthy children. © 2001 John Wiley & Sons, Inc. J Clin Ultrasound 29:326,331, 2001. [source] Isomers of C20: An energy profile IIJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 11 2003Kyle A. Beran Abstract Semi-empirical calculations, at the PM3 level provided within the Winmopac v2.0 software package, are used to geometrically optimize and determine the absolute energies (heats of formation) of a variety of C20 isomers that are predicted to exist in and around the bowl and cage isomers. Using the optimized Cartesian coordinates for the bowl and the cage isomers, a saddle-point calculation was performed. The output file generated, containing energy, distance, and geometry information, is then organized into a graphical format. The resulting graph, which plots the energy of the 20-atom system as a function of the distance from the geometric midpoint, is a two-dimensional energy profile. This profile illustrates an estimation of the contours on the potential energy surface, showing energy minima and maxima that are encountered as the bowl evolves into the cage structure, or vice-versa. To expand the surface into three dimensions, geometry optimizations were performed on the sets of Cartesian coordinates that correspond to energy minima in the bowl-cage profile. Based on these optimizations, eight additional isomers of C20 have been identified and are predicted to be energetically stable. These additional isomers were subsequently subjected to saddle-point calculations in order to identify those isomers that lie adjacent to one another on the three-dimensional surface. Two isomers that are adjacent to each other will exhibit an energy profile that progresses smoothly from the potential well of each isomer up to the saddle point separating them. Consequently, these adjacent pairs of isomers establish a step-wise transformation between the bowl and the cage. This process, which extends out over the three-dimensional surface, is predicted to require less energy than that of the direct, two-dimensional transformation predicted in the bowl-cage profile. © 2003 Wiley Periodicals, Inc. J Comput Chem 24: 1287,1290, 2003 [source] Recentering and Realigning the SAT Score Distributions: How and WhyJOURNAL OF EDUCATIONAL MEASUREMENT, Issue 1 2002Neil J. Dorans The process employed to produce the conversions that take scores from the original SAT scales to recentered scales, in which reference group scores are centered near the midpoint of the score-reporting range, is laid out. For the purposes of this article, SAT Verbal and SAT Mathematical scores were placed on recentered scales, which have reporting ranges of 920 to 980, means of 950, and standard deviations of 11. (The 920-to-980 scale is used in this article to highlight the distinction between it and the old 200-to-800 scale. In actuality, recentered scores were reported on a 200-to-800 scale.) Recentering was accomplished via a linear transformation of normally distributed scores that were obtained from a continuized, smoothed frequency distribution of original SAT scores that were originally on augmented two-digit scales (i.e., discrete scores rounded to either 0 or 5 in the third decimal place). These discrete scores were obtained for all students in the 1990 Reference Group using 35 different editions of the SAT spanning October 1988 to June 1990. The performance of this 1990 Reference Group on the original and recentered scales is described. The effects of recentering on scores of individuals and the 1990 Reference Group are also examined. Finally, recentering did not occur solely on the basis of its technical merit. Issues associated with converting recentering from a possibility into a reality are discussed. [source] Band-related leg injuries in an Australian passerine and their possible causesJOURNAL OF FIELD ORNITHOLOGY, Issue 2 2006Kate Splittgerber ABSTRACT We examined the extent and causes of band-related leg injuries in an Australian passerine, the Bell Miner (Manorina melanophrys). Eight percent of banded birds exhibited leg injuries, and most were birds with two plastic color bands on a tarsus. Leg injuries typically followed the accumulation of shed tarsal scales under the color bands. Color bands used on Bell Miners were tighter on the tarsus than the metal band and also tighter than the color bands used on Superb Fairy-wrens (Malurus cyaneus), a commonly banded species with no reported leg injuries. The tendency for scales to accumulate under two plastic color bands appeared to be influenced by the diameter of a band relative to the size of a bird's tarsus (with looser bands less likely to cause accumulation) and the material used to make the band (with smoother surfaces less likely to cause accumulation). Celluloid color bands had rougher internal surfaces than either Darvic or metal bands. In addition, both celluloid and Darvic color bands generated static electricity capable of attracting tarsal scales. Scales that accumulated under bands provided an environment where potentially harmful fungi became established, potentially contributing to the severity of leg injuries. Our results suggest that, when selecting an appropriate band size for a bird, the diameter of the tarsus at its midpoint should occupy only between 60% and 65% of the internal diameter of the band and, when possible, a single, bicolored, anodized aluminum alloy band should be used instead of multiple plastic color bands. SINOPSIS Examinamos la causa y la extensión de lesiones en las patas causadas por anillas en Manorina melanophrys, en Australia. Un 8% de las aves mostraron lesiones en las patas, la mayoría aves con dos anillas plásticas. Las lesiones causaron la acumulación de escamas tarsales mudadas, bajo la anilla. Se encontraron que las anillas plásticas ejercían mas presión o estaban más ajustadas que las anillas de metal y que estaban más apretadas que en Malurus cyaneus, una especie comúnmente anillada y en donde no encontramos lesiones. La tendencia de acumulación de escamas bajo las dos anillas plásticas, parece ser influenciada por el diámetro de la anilla, con respecto al grosor del tarso del ave y del material con que estuvo echo la anilla. Encontramos que las anillas de celuloide tienen una superficie interna más áspera que las anillas de metal. Además, ambos tipos de anillas, generan estática capaz de atraer las escama de la pata. Las partículas de escama que se acumulan bajo una anilla proveen de una buena base para que se crezcan hongos, que contribuyen a la gravedad de la lesión en la pata. Sugerimos que se deben seleccionar anillas apropiadas en tamaño en donde el diámetro del tarso en la parte media de la pata, ocupe entre el 60,65% del diámetro interno de la anilla. También, que cuando sea posible, se utilice una sola anilla de metal pintada con dos colores, en vez de dos anillas plásticas. [source] EVALUATION OF IDEAL WINE AND CHEESE PAIRS USING A DEVIATION-FROM-IDEAL SCALE WITH FOOD AND WINE EXPERTSJOURNAL OF FOOD QUALITY, Issue 3 2005MARJORIE KING ABSTRACT Most information regarding the suitability of wine and cheese pairs is anecdotal information. The objective of this research was to provide recommendations based on scientific research for the most desirable "wine & cheese pairs" using nine award-winning Canadian cheeses and 18 BC wines (six white, six red and six specialty wines). Twenty-seven wine and food professionals rated the wine and cheese pairs using a bipolar structured line scale (12 cm). The "ideal pair," scored at the midpoint of the scale, was defined as a wine and cheese combination where neither the wine nor the cheese dominated. For each cheese, mean deviation-from-ideal scores were determined and evaluated by analysis of variance. Scores closest to six were considered "ideal," while higher or lower scores represented pairs where the "wine" or the "cheese" dominated, respectively. In general, white wines had mean scores closer to six ("ideal") than either the red or specialty wines. The late harvest, ice and port-type wines were more difficult to pair . Judges varied considerably in their individual assessments reflecting a high degree of personal expectation and preference. [source] Distributed midpoint chain scission in ultrasonic degradation of polymersAICHE JOURNAL, Issue 9 2004G. Sivalingam Abstract The ultrasonic degradation of poly(bisphenol A carbonate), poly(,-caprolactone), and poly(vinyl acetate) was investigated with various solvents such as benzene, monochlorobenzene, and dichlorobenzene. The time evolution of molecular weight was determined using gel permeation chromatography. A limiting molecular weight was observed for all the systems and was a function of solvent properties. The degradation rates increased with increase in viscosity and decrease in vapor pressure. The polydispersity reached a maximum before reaching a constant value at longer times. The experimental data indicate that the breakage of the polymer is around midpoint, with a distribution rather than an ideal midpoint scission. A continuous distribution model with a stoichiometric kernel based on Lorentzian probability distribution function was developed to satisfactorily model the experimental data. © 2004 American Institute of Chemical Engineers AIChE J, 50: 2258,2265, 2004 [source] Kinematics of the ACL-deficient canine knee during gait: Serial changes over two yearsJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 5 2004Scott Tashman Abstract The ACL-deficient dog is a model for investigating the development and progression of mechanically driven osteoarthrosis of the knee. ACL loss creates dynamic instability in the ACL-deficient knee which presumably leads to progressive joint degeneration, but the nature of this instability over the time course of disease development is not well understood. The goal of this study was to characterize three-dimensional motion of the canine knee during gait, before and serially for two years after ACL transection. Canine tibial-femoral kinematics were assessed during treadmill gait before and serially for two years after ACL transection (ACL-D group; 18 dogs) or sham transection (ACL-I group; five dogs). Kinematic data was collected at 250 frames/s using a biplane video-radiographic system. Six degree-of-freedom motions of the tibia relative to the femur were calculated, and values immediately prior to pawstrike as well as the maximum, minimum, midpoint and range of motion during early/mid stance were extracted. Between-group differences relative to baseline (pre-transection) values, as well as changes over time post-transection, were determined with a repeated-measures ANCOVA. In the ACL-D group, peak anterior tibial translation (ATT) increased by 10 mm (p < 0.001), and did not change over time (p = 0.76). Pre-pawstrike ATT was similar to ACL-intact values early on (2,4 months) but then increased significantly over time, by 3.5 mm (p < 0.001). The range of ab/adduction motion nearly doubled after ACL loss (from 3.3° to 6.1°). The magnitude (midpoint) of knee adduction also increased significantly over time (mean increase 3.0°; p = 0.036). All changes occurred primarily between 6 and 12 months. There were no significant differences between groups in the transverse plane, and no significant changes over time in the ACL-I group. In summary, peak anterior tibial translation and coronal-plane instability increased immediately after ACL loss, and did not improve with time. ATT just prior to pawstrike and mean knee adduction throughout stance became progressively more abnormal with time, with the greatest changes occurring between 6 and 12 months after ACL transection. This may be due to overload failure of secondary restraints such as the medial meniscus, which has been reported to fail in a similar timeframe in the ACL-deficient dog. The relationships between these complex mechanical alterations and the rate of OA development/progression are currently under investigation. © 2004 Published by Elsevier Ltd. on behalf of Orthopaedic Research Society. [source] Longitudinal linkages between perceived social support and posttraumatic stress symptoms: Sequential roles of social causation and social selectionJOURNAL OF TRAUMATIC STRESS, Issue 3 2008Krzysztof Kaniasty The authors examined social causation and social selection explanations for the association between perceptions of social support and psychological distress. Data came from a sample of 557 victims of natural disaster in Mexico. Structural equation modeling analyses indicated that social causation (more social support leading to less posttraumatic stress disorder [PTSD]) explained the support-to-distress relationship in the earlier postdisaster phase, 6 to 12 months after the impact. Both causal mechanisms emerged as significant paths in the midpoint of the study (12 and 18 months). Only social selection (more PTSD leading to less social support) accounted for the support-to-distress relationship at 18 to 24 months after the event. Interpersonal and social dynamics of disasters may explain why these two contrasting causal mechanisms emerged over time. [source] Phylogenetic autocorrelation and heritability of geographic range size, shape and position of fiddler crabs, genus Uca (Crustacea, Decapoda)JOURNAL OF ZOOLOGICAL SYSTEMATICS AND EVOLUTIONARY RESEARCH, Issue 2 2010J. C. Nabout Abstract The aim of this study was to evaluate the levels of phylogenetic heritability of the geographical range size, shape and position for 88 species of fiddler crabs of the world, using phylogenetic comparative methods and simulation procedures to evaluate their fit to the neutral model of Brownian motion. The geographical range maps were compiled from literature, and range size was based on the entire length of coastline occupied by each species, and the position of each range was calculated as its latitudinal and longitudinal midpoint. The range shape of each species was based in fractal dimension (box-counting technique). The evolutionary patterns in the geographical range metrics were explored by phylogenetic correlograms using Moran's I autocorrelation coefficients, autoregressive method (ARM) and phylogenetic eigenvector regression (PVR). The correlograms were compared with those obtained by simulations of Brownian motion processes across phylogenies. The distribution of geographical range size of fiddler crabs is right-skewed and weak phylogenetic autocorrelation was observed. On the other hand, there was a strong phylogenetic pattern in the position of the range (mainly along longitudinal axis). Indeed, the ARM and PVR evidenced, respectively, that ca. 86% and 91% of the longitudinal midpoint could be explained by phylogenetic relationships among the species. The strong longitudinal phylogenetic pattern may be due to vicariant allopatric speciation and geographically structured cladogenesis in the group. The traits analysed (geographical range size and position) did not follow a Brownian motion process, thus suggesting that both adaptive ecological and evolutionary processes must be invoked to explain their dynamics, not following a simple neutral inheritance in the fiddler-crab evolution. Resumen El objetivo de este trabajo fue estimar los niveles de herencia filogenética existentes en la posición geográfica, forma y el tamaño de rango geográfico en 88 especies de cangrejo violinista del mundo, mediante simulaciones y métodos comparativos filogenéticos para así evaluar su ajuste al modelo neutro de evolución browniana. Los mapas de rango geográfico se obtuvieron de la literatura. La forma de rango geográfico fue estimada en la dimensión fractal. Los patrones evolutivos en el tamaño y forma del rango geográfico y la posición geográfica fueron explorados mediante correlogramas filogenéticos utilizando el índice I de Moran, coeficientes autorregresivos (ARM) y regressión por autovetores filogenéticos (PVR). Estos correlogramas fueron comparados con aquellos obtenidos mediante la simulación de procesos de evolución browniana en las filogenias. El tamaño y forma de rango geográfico del cangrejo violinista mostró una distribución apuntada hacia la derecha aunque no se encontró autocorrelación filogenética. Por otra parte, se observó un marcado patrón filogenético para la posición geográfica del rango (principalmente a lo largo del eje longitudinal). De hecho, el ARM y PVR evidenció respectivamente que cerca del 86% y 91% de la localización del punto medio longitudinal del rango se puede explicar mediante las relaciones filogenéticas existentes entre las especies. El fuerte patrón filogenético en la longitud podría ser debido a especiación alopátrica y a una cladogénesis estructurada geográficamente para el grupo, tal y como se propuso en las hipótesis. Los rasgos analizados (rango geográfico y posición geográfica) no siguieron un proceso de evolución browniana, sugiriendo pues que tanto los procesos evolutivos como la adaptación ecológica deberían ser tenidos en cuenta para explicar sus dinámicas, ya que el transcurso de la evolución del cangrejo violinista no se explica mediante un simple modelo de herencia neutra. [source] Parent age differentially influences offspring size over the course of development in Laysan albatrossJOURNAL OF ZOOLOGY, Issue 1 2008D. C. Dearborn Abstract Offspring growth and survival are predicted to be higher for older parents, due to a variety of mechanisms, such as increased breeding experience or greater investment favored by low residual reproductive value. Yet the extent to which parent age affects offspring viability is likely to vary between different aspects of growth and survival, perhaps being most pronounced at the most stressful stages of reproduction. We studied the link between parent age and nestling growth and survival in the Laysan albatross, a long-lived seabird with a mean first breeding age of 8 years. Offspring of older parents were more likely to survive to fledging. Among those that did fledge, nestlings of older parents grew more rapidly. However, parent age did not influence the eventual asymptotic size that nestlings reached before fledging: fast-growing nestlings of older parents reached 90% of asymptotic size roughly 1 week sooner, but slow-growing nestlings of younger parents eventually caught up in size before fledging. Older parents bred c. 2 days earlier than younger parents, but hatch date did not explain observed variation in offspring success. The extent to which parent age accounted for variation in size of individual nestlings was not constant but peaked near the midpoint of development. This could reflect a time period when demands on parents reveal age-based differences in parental quality. Overall, growth and survival of offspring increased with parent age in this species, even though the late age of first breeding potentially provides a 7-year period for birds to hone their foraging skills or for selection to eliminate low-quality individuals. [source] Simplified standardized technique for living donor liver transplantation using left liver graft plus caudate lobeLIVER TRANSPLANTATION, Issue 11 2004Shin Hwang Concomitant resection of the caudate lobe (CL) would increase the liver mass in the left liver graft. We tried to define a simplified standardized technique for adult living donor liver transplantation using the extended left lobe (ELL) plus CL (ELLC) through a prospective study of 27 consecutive ELLC graft cases in 2003. Donor CL was dissected toward the 10 o'clock direction and transected at the midpoint between the trunks of the right hepatic vein (RHV) and the middle hepatic vein (MHV). This orthodox transection was performed in 18 cases, but the transection plane was moved left in 9 cases. Compared with conventional left liver implantation, there was no additional reconstruction except for single revascularization of the largest short hepatic vein of the CL (V1) in 21 cases. On 1-week computed tomography (CT) images, the perfusion states of the CL portion were good in 15 cases, fair in 7 cases, and poor in 5 cases. Regeneration of the CL portion during the 1st week was +43%, +18%, and ,10% in the good, fair, and poor perfusion groups, respectively. There were positive correlations among the perfusion state of the CL, the location of the CL transection plane, and the width of the CL portion that was attached to the left liver graft. CL implantation resulted in a mean gain of graft mass by 5.9% in the left liver at the time of operation and by 3.9% after 1 week. There were no donor complications, and 25 recipients (93%) survive to date. In conclusion, this simplified standardized technique was feasible for most of the living donor livers and required only 1 additional reconstruction of the V1. (Liver Transpl 2004;10:1398,1405.) [source] Anterior sciatic nerve block , new landmarks and clinical experienceACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 4 2005M. Wiegel Background: Anterior sciatic nerve blocks can be complicated by several problems. Pain can be caused by bony contacts and, in obese patients, identification of the landmarks is frequently difficult. Methods: In a first step, 100 normal anterior-posterior pelvic X-rays were analyzed. The landmarks of the classical anterior approach were drawn on these X-rays and assessed for their sufficiency. Then, in a prospective case study, 200 consecutive patients undergoing total knee replacement were investigated. These patients received femoral and sciatic nerve catheters for postoperative pain management. Using modified anatomical landmarks, sciatic nerve catheters were inserted 5 cm distal from the insertion site of the femoral nerve block perpendicularly in the midline of the lower extremity. This midline connected the insertion site of the femoral nerve catheter to the midpoint between the medial and lateral epicondyle. Correct catheter positioning was verified by magnetic resonance imaging (MRI) in six patients. Results: Evaluation of pelvic X-rays showed that puncture following the classical landmarks pointed in 51% at the lesser trochanter, in 5% medial to the lesser trochanter and in 42% directly at the femur. In the latter patients, location of the sciatic nerve would have been difficult or even impossible. Using our modified anterior approach, the sciatic nerve could be blocked in 196 patients (98%). In nine patients (4.5%) blockade of the posterior femoral cutaneous nerve failed. Vascular puncture happened in 10 (5%) and bony contact in 35 patients (17.5%). Median puncturing depth was 9.5 (7.5,14) cm. Correct sciatic nerve catheter positioning was verified in all patients who underwent MRI. Conclusion: Our landmarks for locating the sciatic nerve help to avoid bony contacts and thereby reduce pain during puncture. Our method reliably enabled catheter placement. [source] 1H chemical shifts in NMR.MAGNETIC RESONANCE IN CHEMISTRY, Issue 1 2005Part 2, Prediction of the 1H chemical shifts of molecules containing the ester group: a modelling, ab initio investigation Abstract The 1H NMR spectra of 24 compounds containing the ester group are given and assigned. These data were used to investigate the effect of the ester group on the 1H chemical shifts in these molecules. These effects were analysed using the CHARGE model, which incorporates the electric field, magnetic anisotropy and steric effects of the functional group for long-range protons together with functions for the calculation of the two- and three-bond effects. The effect of the ester electric field was given by considering the partial atomic charges on the three atoms of the ester group. The anisotropy of the carbonyl group was reproduced with an asymmetric magnetic anisotropy acting at the midpoint of the carbonyl bond with values of ,,parl and ,,perp of 10.1 × 10,30 and ,17.1 × 10,30 cm3 molecule,1. An aromatic ring current (=0.3 times the benzene ring current) was found to be necessary for pyrone but none for maleic anhydride. This result was confirmed by GIAO calculations. The observed 1H chemical shifts in the above compounds were compared with those calculated by CHARGE and the ab initio GIAO method (B3LYP/6,31G**). For the 24 compounds investigated with 150 1H chemical shifts spanning a range of ca 10 ppm, the CHARGE model gave an excellent r.m.s. error (obs , calc) of <0.1 ppm. The GIAO calculations gave a very reasonable r.m.s. error of ca 0.2 ppm although larger deviations of ca 0.5 ppm were observed for protons near to the electronegative atoms. The accurate predictions of the 1H chemical shifts given by the CHARGE model were used in the conformational analysis of the vinyl esters methyl acrylate and methyl crotonate. An illustration of the use of the CHARGE model in the prediction of the 1H spectrum of a complex organic molecule (benzochromen-6-one) is also given. Copyright © 2004 John Wiley & Sons, Ltd. [source] Anatomic basis of perforator flaps of medial vastus muscleMICROSURGERY, Issue 1 2008Heping Zheng Ph.D. The purpose of this study was to elucidate anatomical features of perforating branch flaps based on the muscular branches of the medial vastus muscle and to seek a new, applicable technique that could be used in repairing soft tissue defects around human knees. In this study, the origin, the course, the branches, the distribution, and the distal anastomosis of the muscular branch of the medial vastus muscle were observed in 30 sides of adult cadaveric lower limb specimens with the adductor tubercle, the patella midpoint, and the inguinal ligament midpoint as the observation markers. The specimens had been perfused arterially with red gelatin before they were supplied. It was observed that the femoral artery gave constant muscular branches into the medial vastus muscle at the tip of the femoral triangle. The artery entered the muscle via the hilum and ran laterally downwards along the muscular bundle until it reached the lateral patella to anastomose with the arterial circle around the bone. Along its course, it also gave 1,3 (1/77%) musculocutaneous perforating branches (0.5,0.9 mm in diameter). It then extended vertically through the medial vastus muscle into the deep fascia and ran superficially to the overlying skin of the muscle. A flap based on the perforating branch of the medial vastus muscle could be harvested at a size of about 8.5 cm × 15.0 cm and might be transferred retrograde to repair the soft tissue defect around the knee. © 2007 Wiley-Liss, Inc. Microsurgery, 2008. [source] Genetic analysis of the strong gyrase site (SGS) of bacteriophage Mu: localization of determinants required for promoting Mu replicationMOLECULAR MICROBIOLOGY, Issue 4 2000M. L. Pato The Mu strong gyrase site (SGS), located in the centre of the Mu genome, is required for efficient Mu replication, as it promotes synapsis of the prophage termini. Other gyrase sites tested, even very strong ones, were unable to substitute for the SGS in Mu replication. To determine the features required for its unique properties, a deletion analysis was performed on the SGS. For this analysis, we defined the 20 bp centred on the midpoint of the 4 bp staggered cleavage made by gyrase to be the ,core' and the flanking sequences to be the ,arms'. The deletion analysis showed that (i) ,,40 bp of the right arm is required, in addition to core sequences, for both efficient Mu replication and gyrase cleavage; and (ii) the left arm was not required for efficient Mu replication, although it was required for efficient gyrase cleavage. These observations implicated the right arm as the unique feature of the SGS. The second observation showed that strong gyrase cleavage and Mu replication could be dissociated and suggested that even weak gyrase sites, if supplied with the right arm of the SGS, could promote Mu replication. Hybrid sites were constructed with gyrase sites that could not support efficient Mu replication. The SGS right arm was used to replace one arm of the strong pSC101 gyrase site or the weaker pBR322 site. The pSC101 hybrid site allowed efficient Mu replication, whereas the pBR322 hybrid site allowed substantial, but reduced, replication. Hence, it appears that optimal Mu replication requires a central strong gyrase site with the properties imparted by the right arm sequences. Possible roles for the SGS right arm in Mu replication are addressed. [source] Continuous sciatic block for leg and foot surgery in 160 childrenPEDIATRIC ANESTHESIA, Issue 11 2005LAKSHMI VAS MD Summary Background:, The aim of this study was to assess the safety and efficacy of continuous sciatic block for lower limb surgery in children. Methods:, A total of 160 pediatric patients aged 4 months to 12 years weighing 3.5,50 kg, were given continuous sciatic block plus single shot 3-in-1 block for leg and foot surgery. After general anesthesia, the sciatic nerve was located by using loss of resistance to saline by the mid-thigh approach. An 18 gauge epidural needle was introduced at the junction of the proximal two-third with the distal one-third of a line extending from the apex of popliteal triangle to the midpoint of the line joining the greater trochanter and the ischial tuberosity. A 20 g catheter was threaded through the needle for 5,10 cm and 0.25% bupivacaine 0.75 ml·kg,1 was injected. A single shot 3-in-1 block was also given to facilitate the use of a tourniquet with 0.25% bupivacaine 0.25 ml. In 20 patients a nerve stimulator was used in addition to loss of resistance. The intraoperative sedation comprised propofol and ketamine infusions and 50% nitrous oxide in oxygen by LMA. Results:, Eight-two percent of patients showed no response to surgery; 14% patients showed some response to the medial incision over the ankle and needed additional bolus doses of ketamine and propofol. Block was considered to have failed in 4% who required an increase in propofol and ketamine infusions. A total of 154 patients had good postoperative pain relief for 72 h with continuous infusion of 0.05% bupivacaine. The other six were given oral codeine and diclofenac. There were no complications attributable to sciatic block in any patient. Conclusions:, Sciatic block with a single shot 3-in-1 block for tourniquet pain and light general anesthesia provides good intraoperative conditions for leg and foot surgery and adequate postoperative pain relief. Additional sedation to minimize the discomfort of a cast may be a consideration in the first 24 h. [source] | |||||||||||||||||||||||||