Managerial characteristics, operational observations, and small business performance: A comparison of US and Mexican ventures

To contribute to our cross-cultural understanding of small business ventures, we investigate manager reports of small business effectiveness in the United States and Mexico. We examine the influence of organizational policies, managerial characteristics, and managerial process observations on reports of business effectiveness. Data were gathered from ventures in both countries, and results showed differences in interpersonal processes, business structure, and gender. Implications for future research are given.     

Exploring the Role of Family Support and Ethnic Pride in Cultivating the Academic and Career Resourcefulness of Underserved Youth in an Afterschool Program

The Urban Review - The purpose of this study was to identify the internal and external factors that support the academic and career resourcefulness of adolescents from underserved backgrounds. This...     

Reliability of force-velocity parameters obtained from linear and curvilinear regressions for the bench press and squat exercises

ABSTRACT

This study aimed to compare the goodness of fit and the reliability of different regression models for fitting the force-velocity relationship (FV) of bench press (BP) and squat (SQ). Additionally, the reliability of the position on FV of the velocity (V_1RM) and the force performed with the 1RM (F_1RM) was explored. Nine rugby players and 12 judokas participated in this study. The FV of BP and SQ were obtained twice by a protocol performed until the 1RM. Individual FV were fitted by linear (LM), quadratic polynomial (PM), and exponential models (EM). Adjusted coefficients of determination of LM and PM (medians higher than 0.919) were higher than for EM. The reliability was higher for LM in comparison with PM. The reliability of V_1RM was not acceptable (CV% = 19 and 18% for BP and SQ). High reliability was observed for F_1RM (CV% = 3 and 2% for BP and SQ) and for the ratio between F_1RM and the force-axis intercept of FV (CV% = 2 and 4% for BP and SQ). The reliability of the relative values of F_1RM around 92 and 87% of F₀ for BP and SQ suggests the use of these values for monitoring resistance training programmes.     

A Rethinking on the Benefits and Drawbacks of Common Antioxidants and a Proposal to Look for the Antioxidants in Allium Products as Ideal Agents: A Review

This review article on the beneficial uses of Allium antioxidants tries to give some answers to the recent doubts raised by Singh et al. (Ind J Clin Biochem 25(3):225–243, 2010) against the claim of some researchers that Antioxidants (AOs) are miraculous molecules. Many people still believe that vitamins like A, C and E are the only true AOs that play important role in the corrections of metabolic derangements in life style diseases and hence all their faults are attributed to the failures of AOs as a class. This is quite unfair as there are many other natural AOs that do equal or even better AO action than the vitamins. Such is the case with the Allium S-alkyl sulfoxide aminoacids and their breakdown products viz, the various poly sulfides and their oxides e.g. allicin and ajoene type compounds which trap electrons mainly. It is true that antioxidant vitamins and β-carotene a precursor of Vitamin A bring about problems as prooxidant or as agents that block some metabolic pathways and gene expression. Again the argument that AOs cannot improve the level of antioxidant enzymes like SOD, catalase and glutathione Px is also not universal. Actually allium AOs can even spare the use of antioxidant vitamins in the body and enhance the action of antioxidant enzymes and supply of ATP and other nutrients to the tissues as the former are good vasodialators and promoters of membrane permeability. The use of AOs should be selective and moderate. Allium AOs satisfy the role of ideal AOs based on many of their invivo and invitro actions reported by the author and others. Their metabolits can regenerate them and recycle them for a sufficient time in the body. They have non antioxidant effects also such as antiplatelet, fibrinolytic, antiinflammatory, immunomodulatory, antiageing actions etc. Plant derived AOs may be more beneficial and better tolerated in their partially purified forms rather than in their absolutely purified forms as the accompanying principles have some protective and regulatory effects in general. This and other aspects of allium AOs are discussed in the paper.     

Sex-differences in elite-performance track and field competition from 1983 to 2015

The purpose of this study was to assess the veracity of the Court of Arbitration for Sport’s assertion that sex-differences in athletic performance in elite-standard track and field competition is of the order of 10–12%. Exponential curves were fitted to the data of selected track and field events of the finals of all IAAF World Championships and Olympic Games from 1983 to 2016. For each curve, the coefficient of determination R² was calculated, in combination the corresponding 95% confidence intervals for the curve constants. Sex-differences were evaluated via differences in the fitted curves between men and women. Mean performances of winners, as well as overall performance means of all participants, were also analyzed. The calculated sex-difference was 8.2 ± 1.0% – 11.8 ± 2.1% for sprints, 10.3 ± 3.3% – 12.8 ± 4.0% for middle and long-distance events, 9.7 ± 2.9% – 13.1 ± 2.9% for relays and 14.2 ± 2.2% – 25.0 ± 4.4% for jumps. This study therefore confirms that the percentage difference accepted by the CAS is appropriate for elite-standard track and field events.     

Goalkeeping in the soccer penalty kick

The goalkeeper’s difficulty in the soccer penalty kick originates from the extreme spatiotemporal constraints of the situation. The present review claims that the current understanding is biased toward attributing a goalkeeper’s success in saving a penalty kick to perceptual–cognitive skill. To investigate the goalkeeper’s skill, researchers have often adopted video tasks. In doing so, they studied perceptual skill in isolation from action. We use affordance-based control theory to propose an alternative understanding and research methodology. We argue that goalkeepers in the penalty kick situation should regulate their actions in ways that sustain the perception of stoppability. To capture this, we outline the building blocks for a required lateral velocity model, in which the goalkeepers’ required actions are scaled to their maximum capabilities. In doing so, we provide new directions for research.     

Hyperandrogenic athletes: performance differences in elite-standard 200m and 800m finals

The purpose of this study was to examine whether the difference in elite-standard track and field performance between women athletes with and without hyperandrogenism reaches the 10–12% difference in performance between men and women, using only results from elite-standard track and field final competitions. Officially available data from two hyperandrogenic women (Caster Semenya and Dutee Chand) were compared with the characteristic performance of 200m and 800m elite-standard finals. The finishing times of Caster Semenya, before her ineligibility to compete in 2009 and after the suspension of the 2011 IAAF Hyperandrogenism Regulations were found to be respectively 1.24% and 1.49% faster than the predicted performance in 800m finals. When compared with the result of the second classified, the difference was respectively 0.65% and 2.08%. The analysis of the finishing times of Dutee Chand did not lead to any conclusions due to the lack of available data. The present study indicates that the percentage difference in performance between women with and women without hyperandrogenism does not reach the 3% difference requested by the Court of Arbitration for Sport for the reinstatement of the Hyperandrogenism Regulations, neither does it reach the 10% accepted range of difference in performance between men and women.     

A case study on the universal compensation-improvement mechanism: A robust PID filter-shaped optimal PI tracker for systems with/without disturbances

Many dynamical systems are continuous-time non-square with unknown mismatched input and output disturbances. For such systems, a universal on-line robust optimal tracking control is often desirable. In this paper, the conventional proportional-integral-differential (PID) controller is utilized as a fictitious PID filter to shape the tracking error in the frequency-domain using a quadratic performance index as a weighting function, such that the robust PID-shaped PI tracker integrated with the equivalent input disturbance (EID) estimator is established to carry out the on-line robust optimal tracking control of the general disturbed system. The benefits and discrepancies of the proposed compensation improvement mechanism over the conventional optimal trackers for continuous-time non-square systems with/without unknown mismatched input and output disturbances are listed as follows: (i) It develops a new net EID estimator without any previously established constraints on the dimensions of the system and on the disturbances; (ii) It provides an efficient estimated-state-feedback-based EID estimator in contrast to the conventional output-feedback-based EID estimators; (iii) It is able to carry out on-line EID estimation of the tracking errors for systems with endogenous/exogenous output disturbances; (iv) It is a universal tracker which can be simply implemented as a plug-in EID estimator for most servo systems, to improve the performance of any existing observers/trackers which are not allowed to be removed from the system. The advantages of the proposed method over two existing outstanding approaches reported in the literature are pointed out using illustrative examples.     

A descriptive profile of junior college presidents

This article reports the results of a nationwide survey of the institutional heads of junior and community colleges. Included are statistics regarding sex, ethnicity, age, educational background, academic rank, salary, length of service, professional affiliations, and publication record.     

Prophylactic Effects of Garlic Oil and Onion Oil Fractions as Compared to Vitamin E on Rats Orally Fed with Lead Acetate Solution

Heavy metal pollution is a global public health challenge due to its stable and persistent environmental contamination. Of these lead is considered to be one of the most common ubiquitous and industrial pollutants and at low concentration it exerts extensive damages to the tissues. Daily feeding of lead acetate solution (Dose: 10 mg/kg/day) to normal rats for a month adversely altered the parameters of blood, serum and tissues, viz; RBC, WBC, Hb, ?- ALAD (Delta amino levulinic acid dehydratase), Pb content, lipids, oxidized lipids (TBARS), vitamins C and E and GSH levels and activities of AST, ALT and antioxidant enzymes viz; catalase, GR, Gpx and SOD. In order to study whether antioxidants have any effect to counteract the toxicity of lead we have selected comparatively better active allium fractions for the study viz: polar fraction of garlic (PFG) and polar fraction of onion (PFO). On feeding of these active fractions of garlic and onion oils i.e. their polar fractions and vitamin E (Dose 100 mg/kg/day) separately for a month along with or without lead acetate to rats each nutraceutical and vitamin E counteracted the adverse effects of Pb significantly (p ≤ 0.05). Their effects are in the order of PFG > PFO > Vitamin E. All these results point out that garlic and onion oils contain natural disulfoxide compounds which act as antioxidant and anti toxic to lead compounds. Their comparative differences in action may be due to the presence and position of double bonds and disulfide oxide bonds in their molecules. i.e., in PFG the allyl disulfide oxide group is present and in PFO saturated methyl and propyl groups and unsaturated propenyl group are present in place of allyl groups. The former group confers a better antioxidant activity on PFG, while the latter groups confer a lesser activity on PFO.