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Subjects Used (subject + used)
Selected AbstractsLimits of spherical blur determined with an adaptive optics mirrorOPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 3 2009David A. Atchison Abstract We extended an earlier study (Vision Research, 45, 1967,1974, 2005) in which we investigated limits at which induced blur of letter targets becomes noticeable, troublesome and objectionable. Here we used a deformable adaptive optics mirror to vary spherical defocus for conditions of a white background with correction of astigmatism; a white background with reduction of all aberrations other than defocus; and a monochromatic background with reduction of all aberrations other than defocus. We used seven cyclopleged subjects, lines of three high-contrast letters as targets, 3,6 mm artificial pupils, and 0.1,0.6 logMAR letter sizes. Subjects used a method of adjustment to control the defocus component of the mirror to set the ,just noticeable', ,just troublesome' and ,just objectionable' defocus levels. For the white-no adaptive optics condition combined with 0.1 logMAR letter size, mean ,noticeable' blur limits were ±0.30, ±0.24 and ±0.23 D at 3, 4 and 6 mm pupils, respectively. White-adaptive optics and monochromatic-adaptive optics conditions reduced blur limits by 8% and 20%, respectively. Increasing pupil size from 3,6 mm decreased blur limits by 29%, and increasing letter size increased blur limits by 79%. Ratios of troublesome to noticeable, and of objectionable to noticeable, blur limits were 1.9 and 2.7 times, respectively. The study shows that the deformable mirror can be used to vary defocus in vision experiments. Overall, the results of noticeable, troublesome and objectionable blur agreed well with those of the previous study. Attempting to reduce higher-order aberrations or chromatic aberrations, reduced blur limits to only a small extent. [source] Low-fat vs. high-fat bedtime snacks in children and adolescents with type 1 diabetesPEDIATRIC DIABETES, Issue 4pt1 2008Darrell Wilson Objective:, The purpose of this study was to determine whether, in a group of children with type 1 diabetes using insulin pump, a prebedtime snack with a relatively high fat content provides greater protection from nocturnal hypoglycemia than a snack containing the same amount of carbohydrate and protein but a lower fat content. Research design and methods:, Ten subjects, aged 6 to <18 yr, in a trial evaluating the Abbott Navigator glucose sensor, agreed to this ancillary study. On 12 or more separate nights, each subject was randomized by a Web site to a carbohydrate,low-fat (30 g CHO, 2.5 g protein, and 1.3 g fat; 138 kcal) snack or a carbohydrate,high-fat (30 g CHO, 2 g protein, and 20 g fat; 320 kcal) snack. Subjects used their usual evening snack algorithm to determine the size (in 15-g carbohydrate increments) and insulin dosage. Results:, Average glucose on 128 valid study nights before snack was similar in both groups. The proportion of nights with hypoglycemia (a sensor or meter glucose value ,70 mg/dL) was similar in both groups (19% high fat vs. 20% low fat), as was the proportion of nights with hyperglycemia (a glucose ,200 mg/dL and at least 50 mg/dL above baseline, 35% high fat vs. 30% low fat). Conclusions:, There were no statistical differences between the high- and low-fat snacks on the frequency of hyperglycemia or hypoglycemia. This study highlights the feasibility of web-based research in patients' home environment. [source] Management of complicated head and neck wounds with vacuum-assisted closure systemHEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 11 2006Brian T. Andrews MD Abstract Background The vacuum-assisted closure system (V.A.C.), or negative pressure dressings, has been successfully used to manage complex wounds of the torso and extremities, but its role in the head and neck region has not been frequently described. Methods A retrospective study was performed. The V.A.C. system (Kinetic Concepts Inc., San Antonio, TX) was used at the University of Iowa Hospitals and Clinics for management of complicated head and neck wounds. Results The V.A.C. system was utilized at 13 sites for 12 patients. Nine subjects had exposed calvarium (4 had failed pedicled reconstructive flaps, 3 had ablative or Moh's defects, and 2 had traumatic scalping injuries) necessitating bony coverage. Three subjects had the V.A.C. system used as a bolster dressing placed over split-thickness skin grafts (STSGs) used to reconstruct large defects of the face and skull, and 1 patient had a large soft tissue neck defect after radical surgical resection for necrotizing fascitis. One subject used the V.A.C. system for the management of 2 distinct wounds. All patients had successful healing of their wounds with the V.A.C. system without complication. All STSGs had 100% viability after 5 to 7 days of the V.A.C. system use as a bolster dressing. Conclusion This study demonstrates the V.A.C. system is a valuable tool in the management of complicated head and neck wounds. © 2006 Wiley Periodicals, Inc. Head Neck, 2006 [source] Method Development for Assessing the Complete Process of Crumbling Cheese Using Hand EvaluationJOURNAL OF FOOD SCIENCE, Issue 4 2004S. Sandra ABSTRACT: Cheese sensory evaluation was conducted by trained panelists (n= 8) on 4 commercial cheese samples (feta, Monterey Jack, 2 brands of Queso Fresco) in duplicate. Fifteen descriptors, capturing the entire process of crumbling cheese, were tested. Degree of crumbliness was defined as the ease by which the sample breaks apart during manipulation by rolling the sample using replicated circular movements, with the thumb, forefinger, and middle finger, 5 times. Using principal component analysis, 4 components were extracted and moistness, crumbliness, color, cohesiveness, irregularity, and oiliness were the main descriptors differentiating the samples. Panelists' performances were not significantly different (P, 0.05), and each subject used the method consistently for crumbliness. [source] Diagnostic reasoning strategies and diagnostic successMEDICAL EDUCATION, Issue 8 2003S Coderre Purpose Cognitive psychology research supports the notion that experts use mental frameworks or ,schemes', both to organize knowledge in memory and to solve clinical problems. The central purpose of this study was to determine the relationship between problem-solving strategies and the likelihood of diagnostic success. Methods Think-aloud protocols were collected to determine the diagnostic reasoning used by experts and non-experts when attempting to diagnose clinical presentations in gastroenterology. Results Using logistic regression analysis, the study found that there is a relationship between diagnostic reasoning strategy and the likelihood of diagnostic success. Compared to hypothetico-deductive reasoning, the odds of diagnostic success were significantly greater when subjects used the diagnostic strategies of pattern recognition and scheme-inductive reasoning. Two other factors emerged as independent determinants of diagnostic success: expertise and clinical presentation. Not surprisingly, experts outperformed novices, while the content area of the clinical cases in each of the four clinical presentations demonstrated varying degrees of difficulty and thus diagnostic success. Conclusions These findings have significant implications for medical educators. It supports the introduction of ,schemes' as a means of enhancing memory organization and improving diagnostic success. [source] Exploratory eye movements during the Benton Visual Retention Test: Characteristics of visual behavior in schizophreniaPSYCHIATRY AND CLINICAL NEUROSCIENCES, Issue 4 2003Shigeru Obayashi Abstract In order to investigate the relationship between the behavioral patterns and clinical symptomatology in schizophrenia, exploratory eye movements of schizophrenic subjects and healthy controls during the Benton Visual Retention Test were examined using an eye-mark recorder. The results were as follows: (i) with card 1, the number of eye fixations of schizophrenic subjects was fewer, and the total and mean eye scanning lengths of schizophrenic subjects were shorter than those of healthy controls; (ii) with card 3, almost none of the schizophrenic subjects looked at the blank area opposite the peripheral figure on the right; (iii) with cards 3, 5, 6 and 9 there were some schizophrenic subjects who did not look at the peripheral figures; (iv) with card 6, many of the schizophrenic subjects made stereotypical movements; (v) with card 9, schizophrenic subjects used a narrow vertical gaze to look at the large figure on the right. Based on these characteristics among the schizophrenic subjects themselves, factors such as longer eye scanning length, looking at peripheral figures without fail, and not making stereotypical movements were reflected directly in the results of the Benton test, while there was no relationship between the width of the vertical gaze and the Benton results. Correlations between visual behavior and some psychiatric symptoms were observed. The visual behavioral patterns of schizophrenic subjects were various according to the characteristics of the Benton figures, while those of normal subjects were always almost the same. It was suggested that these results were caused by disturbances of the mental attitude of schizophrenic subjects toward objects or environments. [source] Not so fast: Speed effects on forelimb kinematics in cercopithecine monkeys and implications for digitigrade postures in primatesAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 1 2009Biren A. Patel Abstract Terrestrial mammals are characterized by their digitigrade limb postures, which are proposed to increase effective limb length (ELL) to achieve preferred or higher locomotor speeds more efficiently. Accordingly, digitigrade postures are associated with cursorial locomotion. Unlike most medium- to large-sized terrestrial mammals, terrestrial cercopithecine monkeys lack most cursorial adaptations, but still adopt digitigrade hand postures. This study investigates when and why terrestrial cercopithecine monkeys adopt digitigrade hand postures during quadrupedal locomotion. Three cercopithecine species (Papio anubis, Macaca mulatta, Erythrocebus patas) were videotaped moving unrestrained along a horizontal runway at a range of speeds (0.4,3.4 m/s). Three-dimensional forelimb kinematic data were recorded during forelimb support. Hand posture was measured as the angle between the metacarpal segments and the ground (MGA). As predicted, a larger MGA was correlated with a longer ELL. At slower speeds, subjects used digitigrade postures (larger MGA), however, contrary to expectations, all subjects used more palmigrade hand postures (smaller MGA) at faster speeds. Digitigrade postures at slower speeds may lower cost of transport by increasing ELL and step lengths. At higher speeds, palmigrade postures may be better suited to spread out high ground reaction forces across a larger portion of the hand thereby potentially decreasing stresses in hand bones. It is concluded that a digitigrade forelimb posture in primates is not an adaptation for high speed locomotion. Accordingly, digitigrady may have evolved for different reasons in primates compared to other mammalian lineages. Am J Phys Anthropol 2009. © 2009 Wiley-Liss, Inc. [source] Dynamic in-hand movements in adult and young juvenile chimpanzees (Pan troglodytes)AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 3 2009Jessica Crast Abstract Descriptions of manual function in nonhuman primates have largely focused on static precision and power grasping (as first defined by Napier,1956), while identification and description of dynamic manual function are rare and incomplete. Here, we describe several forms of in-hand movements used by chimpanzees (Pan troglodytes) when manipulating small objects. In-hand movements are defined as the movement of an object within one hand via manipulation of the digits. We presented adult and young juvenile chimpanzees (ages 5,29 years) with a task that required inserting small objects through correspondingly shaped cutouts in a transparent Plexiglas panel. While attempting to insert the objects through the cutouts, the subjects used at least two forms of in-hand movements to change their grip on the object for more precise alignment. We describe in detail the in-hand movements they used and the variability observed in form and execution among the subjects. In general, the adult subjects used in-hand movements more frequently and used a wider variety of forms than did the young juvenile subjects, suggesting that in-hand movements are in the process of fine-tuning around the age of 5 years in chimpanzees. The dexterity exhibited by the adults, however, shows that the neuromuscular and morphological requirements for relatively complex digital manipulation are present in the adult chimpanzee. Am J Phys Antropol, 2009. © 2008 Wiley-Liss, Inc. [source] Complementing Mass Customization Toolkits with User Communities: How Peer Input Improves Customer Self-Design,THE JOURNAL OF PRODUCT INNOVATION MANAGEMENT, Issue 6 2008Nikolaus Franke In this paper, the authors propose that the canonical customer,toolkit dyad in mass customization (MC) should be complemented with user communities. Many companies in various industries have begun to offer their customers the opportunity to design their own products online. The companies provide Web-based MC toolkits that allow customers who prefer individualized products to tailor items such as sneakers, personal computers (PCs), cars, kitchens, cereals, or skis to their specific preferences. Most existing MC toolkits are based on the underlying concept of an isolated, dyadic interaction process between the individual customer and the MC toolkit. Information from external sources is not provided. As a result, most academic research on MC toolkits has focused on this dyadic perspective. The main premise of this paper is that novice MC toolkit users in particular might largely benefit from information given by other customers. Pioneering research shows that customers in the computer gaming and digital music instruments industries are willing to support each other for the sake of efficient toolkit use (e.g., how certain toolkit functions work). Expanding on their work, the present paper provides evidence that peer assistance appears also extremely useful in the two other major phases of the customer's individual self-design process, namely, the development of an initial idea and the evaluation of a preliminary design solution. Two controlled experiments were conducted in which 191 subjects used an MC toolkit to design their own individual skis. The authors found that during the phase of developing an initial idea, having access to other users' designs as potential starting points stimulates the integration of existing solution chunks into the problem-solving process, which indicates more systematic problem-solving behavior. Peer customer input also turned out to have positive effects on the evaluation of preliminary design solutions. Providing other customers' opinions on interim design solutions stimulated favorable problem-solving behavior, namely, the integration of external feedback. The use of these two problem-solving heuristics in turn leads to an improved process outcome,that is, self-designed products that meet the preferences of the customers more effectively (measured in terms of perceived preference fit, purchase intention, and willingness to pay). These findings have important theoretical and managerial implications. [source] Long-Term Performance of Clarion 1.0 Cochlear Implant Users,THE LARYNGOSCOPE, Issue 7 2007Chad V. Ruffin BS Abstract Objective/Hypothesis: To evaluate the long-term performance of adult Clarion 1.0 cochlear implant users. Study Design: This was a retrospective, longitudinal study evaluating word discrimination in quiet for 31 adult cochlear implant patients with preimplantation sentence scores of less than 10%. Methods: The length of the study was 135 months with a mean follow-up length of 93 (median, 96) months. For the duration of the study, all subjects used the Clarion 1.0 cochlear implant with speech processors programmed for the use of the continuous interleaved sampling strategy. Results: There was no significant growth or decline in speech perception after 24 months postimplantation unless adverse medical events were experienced. Age at implantation was significantly and substantially negatively correlated (,11% word score per decade, r = 0.68) with most recent score, maximum score, time to maximum score, range of performance, 24- to 130-month mean score, and for any longitudinal data point tested: 3 to 6 months, 6 months, 1 year, 2 years, 5 years, and 10 years. There were no age-related declines in performance. There were no observed correlations between duration of deafness and any of the variables listed above. Conclusions: The lack of correlation between duration of deafness and performance in a cohort without residual hearing suggests the presence of a strong correlation between age and speech performance with a cochlear implant. That the cochlear implant is a safe therapy for the treatment of profound deafness is supported by the stability of scores through the 10-year study period as well as a zero rate of device failures or explantation. [source] Age-related changes in skin wrinkles assessed by a novel three-dimensional morphometric analysisBRITISH JOURNAL OF DERMATOLOGY, Issue 4 2002S. Akazaki SummaryBackground,A system has been developed whereby the morphology of the skin surface can be evaluated directly in three dimensions. This system employs a non-invasive device that utilizes white light of halogen origin, and which allows the computation of wrinkle depth and width, and other parameters of skin surface morphology. Using innovative engineering, an optical system has been devised so that light is transmitted via a slit and can be used to measure not only replicas of the skin but also the skin surface directly. The measurement area is 6·4 × 6·4 mm, and the theoretical resolution with a × 50 magnification lens is within 12·5 µm. Objectives,To use this system to study age-related changes in the morphology of wrinkles at the eye corner areas of women of varying ages. Methods,One hundred and one healthy women (age range 20,80 years) residing in the Tokyo area were the subjects used in this study. Results,Wrinkles demonstrated a rapid increase in depth in women aged 40 years or older, and plateaued at the age of 60 years. Surface morphology parameters yielded results similar to those of age-related changes in wrinkles. Conclusions,This new analytical system provides a rapid and convenient non-invasive method to evaluate skin surface morphology in three dimensions, especially with respect to wrinkle formation. The results obtained using this system provide a deeper insight into the mechanistic relationship between wrinkles and skin elasticity. [source] The frequency of absence of palmaris longus in a South African population of mixed raceCLINICAL ANATOMY, Issue 4 2010Robert Ndou Abstract The palmaris longus (PL) is a weak flexor of the wrist that may be harvested as a tendon graft and used in surgical procedures for reconstructive purposes. The PL is congenitally absent in 15% of the worldwide population. However, the frequency of absence varies considerably among different population groups, being as high as 63.9% in the Turkish population and as low as 3% in the black population in the Republic of Congo. In this study, South African persons of mixed race (n = 201) were assessed by two anatomists for the presence of the PL tendon using three clinical tests, namely the Traditional Test, Mishra's Test II, and the Gangata Test. The most reliable of the three tests used was determined using Kendall's coefficient of concordance. Of the total number of subjects used, 11.5% had absence (either bilaterally or unilaterally) of the PL tendon. There was a 5.5% bilateral absence of the PL. The study revealed that the PL tendon may present in six different patterns according to the clinical assessment tests applied, the presence or absence of the PL alongside the flexor capi radialis, and the degree of prominence of PL, if present. Using the Kendall's coefficient of concordance, the Mishra's Test II, and the Gangata Test, both involving abduction of the thumb, were found to be most effective in revealing the PL. The frequency of absence of the PL in South Africans of mixed race has been determined. Clin. Anat. 23:437,442, 2010. © 2010 Wiley-Liss, Inc. [source] | |||||||||||||