416 research outputs found

    Kant on Empirical Objects: Their Reality and Persistence As Contrasted With Hume's Scepticism

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    Can we be realists about objects as persistent entities about which empirical knowledge claims are formulated? And do we need to rely on objects persisting by perduring or enduring in order to decide this issue? examine this topic first by Humean and then Kantian lights, in an attempt to formulate Kant's assumptions and his account of objects and our knowledge of them, both as a reaction to and as continuation of Hume's abortive sceptical enquiry. I distinguish three sceptical arguments in Hume, two of knowledge in general and one of knowledge of empirical objects in particular, the latter being in essence a more detailed version of the logical argument as applied to objects. These arguments have different grounds; of the two general arguments, one is psychological and the other logical. I conclude that the psychological argument is unconvincing, and that while both logical arguments are sound on a certain reading, Hume fails to take into account an ambiguity in his assumptions which makes scepticism avoidable. This has two results. First, taking scepticism about empirical objects to be avoidable on Hume's assumptions is consistent with their persisting either by perduring or enduring. Second, there is no need for Hume to abandon rational means for arriving at knowledge of an objective world. I explore the latter consequence in Kant, who has such a rational account, one which sets forth a rebuttal of Hume's scepticism and provides both an epistemology and empirical ontology of objects. However, Kant's derivation of an external world using Hume's subject-first or experience-first approach is faulty. for it assumes what it sets out to prove. This is not disastrous. for against Hume Kant does not need to prove the existence of an external world, he only needs to assume an objective world. This is a reasonable assumption, and as I show. Kant's system provides a plausible epistemology based on it, in which knowledge of persistent empirical objects is a necessary consequence of taking experience as essentially subjective or first-personal. On this account. however, ontologically the question whether objects are entities or composed of parts which are entities is indeterminate, for although objects are identified as relatively permanent when described as causes, experience can be described in non-mutually exclusive ways which are consistent with both the persistence and non-persistence over a period of time of any given object. Thus Kant's account is by default consistent in principle both with objects which persist by perduring and those which persist by enduring, merely because as it stands it does not provide a means of deciding the issue. Finally, both particular and general difficulties found with Kant's system and fruitful avenues of further research are discussed

    Intrinsic Anthropometric Factors Associated with Bone Stress Injuries in Collegiate Runners: New Risk Metrics & Novel Field Screening Tools

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    Lower extremity bone stress injuries (BSI) (i.e. pelvis, femur, tibia) are common in distance running athletes relative to other sports. PURPOSE: To (1) characterize bone mineral density (BMD), body composition (BComp, DXA), and anthropometric parameters in D1A collegiate runners presenting with and without BSIs during a collegiate season and (2) develop BMD prediction models with an accompanying mobile application for novel noninvasive field prediction of BMD and BSI risk. METHODS: Distance runners (n = 79; 42♂, 37♀) from a single university track and field team were retrospectively enrolled into study. The runners completed a DXA scan during fall screening (August-November). Three months after scanning, medical records were reviewed for the occurrence of BSI confirmed by a licensed physician. A t-test was used to compare BMD (total and regional [spine, pelvis, and legs]), BComp (% body fat, fat mass, and lean mass), and anthropometric measurements (shoulder width and leg, arm, and trunk length) between runners with versus without BSI (included subgroup analysis by sex). Multiple linear regression with stepwise removal was used to determine variables most predictive of BMD. Xcode (Apple Inc.) was used to develop the mobile application based on the derived BMD prediction models utilizing lower-bound 95% confidence intervals for runner-specific BMD norms as risk cutoffs. RESULTS: Eighteen runners (22.8%; 11♀, 7♂) sustained a lower limb BSI. Compared to the noninjured group (NoBSI), injured runners (BSI) had lower total BMD (NoBSI: 1.24 0.02, BSI: 1.15 0.04, p\u3c0.001) and regional BMD (spine -11%, legs -9%, pelvis -10%, p\u3c0.001). Injured athletes were observed to have shorter leg length (NoBSI: 95.6 1.4cm, BSI: 91.9 2.6cm, p=0.015) and arm length (NoBSI: 56.1 0.8, BSI: 53.8 1.5, p=0.006). Injured males had lower fat mass (NoBSI: 7.7 0.5kg, BSI: 6.4 0.7cm, p=0.041) and injured females had lower leg lean mass (NoBSI: 14.7 0.6kg, BSI: 13.5 0.7kg, p=0.035). BComp and anthropometric measures were predictive of bone mass (p\u3c0.05, R2 =0.61; SE= ±0.27kg) and BMD (Total: p\u3c0.05, R2 =0.77; SE= ±0.05g/cm2). BONE MASS, kg = (0.046 x Ageyears) +(0.024 x Weightkg) +(0.014 x %BodyFat) +(-0.017 x Arm Lengthcm) +(0.017 x Shoulder Widthcm) +(-0.009 x Trunk Lengthcm) +(0.037 x Leg Lengthcm) -2.867] | BMD, g cm2 =(-0.011 x %BodyFat) + (0.016 x Fat Mass kg) + (0.203 x Bone Masskg) +(-0.003 x Leg Lengthcm) +1.023. The mobile application was able to successfully run the developed prediction models for BMD assessment. CONCLUSION: Collegiate distance runners with shorter limb lengths, reduced fat mass(♂), reduced leg lean mass(♀), and lower BMD are at an increased risk for a lower extremity BSI. BComp and anthropometric measures are predictive of BMD in this population and may be utilized with the mobile application developed here as a screening tool to identify potentially “at-risk” runners

    Repair of a wide sternal cleft in a young female

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    AbstractSternal clefts are rare congenital malformations of the anterior chest wall. Surgical correction is typically recommended as early as possible due to the compliance and growth potential of the infant sternum. Several operative techniques have been employed with great success. However, there is a paucity of data regarding repair in large clefts refractory to standard reparative techniques. We report the successful surgical repair in a 15-month-old female with an excessively large, superior sternal cleft

    Anthropometric Factors Associated With Bone Stress Injuries in Collegiate Distance Runners: New Risk Metrics and Screening Tools?

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    Background: Lower limb bone stress injury (BSI) of the pelvis, femur, and tibia is prevalent in collegiate track and field distance runners. Bone mineral density (BMD), body composition (BComp), and anthropometric parameters before initial collegiate injury have not been compared between runners with BSI and their noninjured counterparts. Purpose: To characterize bone health in relation to BComp and anthropometric measurements from total-body dual x-ray absorptiometry (DXA) scans in collegiate male and female distance runners before BSI and develop BMD prediction models. Study Design: Case-control study; Level of evidence, 3. Methods: Distance runners (N = 79) from a single university track and field team were retrospectively enrolled into this study. The runners completed a DXA scan during the fall season (August-November) and participated in sport activities before the scan. Three months after scanning, electronic medical records were reviewed for the occurrence of BSI. An independent-sample t test was used to compare BMD (total and regional [spine, pelvis, and legs]), BComp (% body fat, fat mass, and lean mass), and anthropometric measurements (shoulder width and leg, arm, and trunk length) between runners with versus without BSI (included subgroup analysis by sex). Multiple linear regression with stepwise removal was used to determine variables most predictive of BMD. Results: Of the 79 enrolled participants (42 male, 37 female), 18 runners (22.8%; 11 female, 7 male) sustained a lower limb BSI. Compared with the noninjured group, injured runners had lower total and regional BMD (P < .001 for all) and shorter leg and arm lengths (P < .05 for both), whereas injured male runners had lower fat mass and injured female runners had lower lean mass in the legs (P < .05 for both). Injured runners’ age-matched total BMD Z score (-0.1 ± 0.6) was considered clinically normal. BComp and anthropometric measures were predictive of total and regional BMD (P < .05; R 2 = 0.64-0.80; percentage error = 3.8%-4.8%). Conclusion: The DXA scans of injured runners prior to incidence indicated lower BMD compared with noninjured runners. Shorter limb lengths, lower fat mass (male), and lower leg lean mass (female) may also be indicative of risk. Certain BComp and anthropometric measures were predictive of BMD

    Prediction of the Total Energy Cost of an Acute Bout of Resistance Exercise in Young Men and Women

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    Prediction of the Total Energy Cost of an Acute Bout of Resistance Exercise in Young Men and Women Brad S. Lambert†, Steven E. Martin‡, John S. Green‡ (FACSM), Aaron F. Carbuhn†, Stephen F. Crouse‡ (FACSM). Department of Health and Kinesiology, Texas A&M University, College Station, TX (Sponsor S.F. Crouse) ACSM currently recommends resistance training (RT) for each major muscle group at least 2 times per week with a traditional repetition range of 8-12 per set. Because many investigators as well as fitness professionals consider kcal expenditure when creating training protocols, energy costs during both RT and aerobic training must be considered. PURPOSE: To develop a regression equation to predict kcal expenditure for a RT bout involving each major muscle group using VO2max, height, weight, lean body mass, fat mass, and total exercise volume (TV=sets*reps*wt) as independent variables. METHODS: Twelve subjects (7 men, 5 women, age 21-25 yrs) were tested using the standard Bruce treadmill protocol for VO2max, and strength tested to determine their 3-5 repetition max (RM) on Keiser® RT equipment 1 week prior to their experimental RT bout. Body composition was assessed using DEXA. For their experimental RT bout, a warm-up set followed by 2-3 sets of 8-12 reps at 60-70% predicted 1RM were performed for each exercise. Each set was started every two minutes. Exercises progressed in the following order: leg press, chest press, leg curl, lat pull, leg ext., triceps ext., biceps curl. Oxygen consumption was measured continuously throughout the RT bout using an automated metabolic cart. Multiple Linear Regression was used to determine the best model for prediction of kcal consumption. Results: Mean kcal expenditure for the entire RT bout was 221.8±20.65 kcal (men = 272±36 & women = 150±16) with a mean kcal cost of 26.32-38.94 per exercise. Large muscle group/multi-joint exercises had the highest total kcal expenditures as expected. Collinearity diagnostics from the regression revealed that VO2max (L/min) and the square root of TV (TV0.5) were the only predictors needed in the model with all other variables being highly intercorrellated with VO2max (L/min), thus not adding significant improvement to the model. The prediction equation was (p\u3c0.05, R2=0.86): Total kcal = (37.264*VO2max L/min) + (1.087*TV0.5) – 132.488 CONCLUSIONS: VO2max (L/min) and TV0.5 were found to be significant predictors of the energy cost of a RT bout involving each major muscle group. In regards to fitness, performance, and weight management, this equation may aid practitioners and young exercising adults in documenting kcal expenditure from resistance training

    Generational differences in practice site selection criteria amongst primary care physicians.

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    Background and Objectives: Generational differences are often viewed as shaping the overall attitudes and actions of different age cohorts. It is essential to understand the motivations and generational differences in primary care physicians for efforts to recruit, retain, and educate the future physician workforce. Determining what factors most influence different generations of primary care physicians when choosing a practice site is essential to build our future primary care system. This study examined generational differences in the factors that attracted primary care physicians to their current practice. Methods: A survey instrument was mailed to all active members of the North Carolina Medical Board who listed their primary occupation as a primary care specialty. The survey consisted of 24 demographic questions regarding personal and practice variables and a list of 21 reasons for choosing a practice location measured on a 7-point Likert type scale. A total of 975 surveys were returned and usable for the final analysis, for a return rate of 34.5%. Data were analyzed using regression and correlation procedures to determine attitudes of each generation and factors that significantly influenced responses. Results: While slight differences between generations did exist, the overall choices for choosing a site remained stable across generations. Personality of the practice, on-call responsibilities, ability to practice comprehensive care, and location were deemed the most important factors for all generations. Differences between various demographic groups and Family Medicine versus other primary care specialties were minor with very little alteration of the top ten items being seen between groups. Conclusion: This study indicated that there were few differences between generations regarding primary reasons for choosing a practice site. In addition, factors remained remarkably similar across different specialties, family situations, genders, and ethnic groups. Several of the top reasons that primary care physicians indicate are the most important for site selection were also potentially modifiable, such as on-call responsibilities, practice personality, and ability to practice comprehensive care. Managers, clinicians, and educators can potentially utilize this information to better prepare and recruit current and future generations of primary care physicians.ECU Open Access Publishing Fun
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