1,024 research outputs found
Acute effects of different warm-up protocols on highly skilled golfers’ drive performance
Previous research has highlighted the positive effect that different warm-up protocols have on golf performance (e.g. Sorbie et al., 2016; Tilley & MacFarlane, 2012) with the design of warm-ups and programmes targeting and improving golf performance through the activation and development of specific muscle groups. This study aimed to examine the acute effects of two warm-up protocols on golf drive performance in comparison to a control condition. Using a randomised counter-balanced design over three testing sessions, twenty-three highly skilled golfers completed the control, dynamic and resistance-band warm-up conditions. Following each condition, a GC2 launch monitor was used to record ball velocity and other launch parameters of ten shots hit with the participants own driver. A repeated-measures ANOVA found significant increases in ball velocity (ηp² = .217) between the control and both the dynamic and resistance-band warm-up conditions but no difference between these latter two, and a reduction in launch angle between control and dynamic conditions. The use of either a dynamic stretching or resistance-band warm-up can have acute benefits on ball velocity but golfers should liaise with a PGA Professional golf coach to effectively integrate this into their golf driving performance
Online Payment Gateways Used to Facilitate E-Commerce Transactions and Improve Risk Management
As online transactions continue to increase and become a significant part of the global economy, the ability to accept payments online becomes more important for businesses. This paper evaluates the literature and provides current information for IS researchers and instructors focusing on electronic commerce. In this paper, we explore the components of e-credit providers (conventional, person-to-person, and third-party) and explain how each system processes a single transaction. We then analyze several market leaders in each segment and summarize the strengths and weaknesses of each company. We provide guidelines for selecting an e-credit provider and highlight the options that apply best to online businesses. Finally, we outline potential areas of future research and provide a simple tutorial on creating a business account with PayPal website Payments Standard as an example of an online payment provider
Calorie Restriction Enhances Longevity Without Reducing Lifetime Fecundity or Glucose Titers in Female Lubber Grasshoppers
Calorie restriction, under eating while avoiding malnutrition, enhances longevity in many organisms, in part by delaying fecundity or lowering blood glucose. Calorie restriction begun at middle-age can also enhance longevity. We tested four diets on longevity of female lubber grasshoppers: ad libitum (free access to food), calorie restriction (60% or 71% of ad libitum), and delayed calorie restriction (60% after day 50). Constant calorie restriction increased longevity in grasshoppers by at least 66%. These diets lowered body mass, but it did not reduce lifetime fecundity or chronically lower blood glucose levels. Calorie restriction reduced the levels of stored protein after egg laying. Delayed calorie restriction also increased longevity (also by 66%), but because the body mass gain of this group did keep pace with ad libitum grasshoppers when they were fed identically, this result needs retesting. These extensions of lifespan likely are due to slowed aging
Short-term resource allocation during extensive athletic competition
© 2017 The Authors. American Journal of Human Biology Published by Wiley Periodicals, Inc. Objectives: Following predictions from life history theory, we sought to identify acute trade-offs between reproductive effort (as measured by psychological arousal) and somatic maintenance (via functional measures of innate immunity) during conditions of severe energetic imbalance. Methods: Sixty-six male ultramarathon runners (ages 20 to 37 years) were sampled before and after a lengthy race. Saliva and sera were collected for testosterone and immunological analyses (hemolytic complement activity and bacterial killing ability). Lean body mass was assessed by bioelectrical impedance, and libido was measured using a slideshow of arousing and neutral images. Results: Following predictions, there was a significant decrease in salivary testosterone levels (109.59 pg/mL versus 97.61 pg/mL, P <.001) and arousal scores in response to provocative images (5.40 versus 4.89, P =.001) between prerace and postrace time points. Additionally, participant bacterial killing ability (P =.035) and hemolytic complement activity (P =.021) increased between prerace and postrace. Conclusions: Decreased libido and testosterone with concomitant heightened innate immune responses suggest a shift in energetic priorities away from reproduction and toward maintenance/defense during a period of energetic stress
International validation of Enhanced Recovery After Surgery Society guidelines on enhanced recovery for gynecologic surgery
Background: Enhanced Recovery After Surgery Society publishes guidelines on perioperative care, but these guidelines should be validated prospectively. Objective: To evaluate the association between compliance with Enhanced Recovery After Surgery Gynecologic/Oncology guideline elements and postoperative outcomes in an international cohort. Study Design: The study comprised 2101 patients undergoing elective gynecologic/oncology surgery between January 2011 and November 2017 in 10 hospitals across Canada, the United States, and Europe. Patient demographics, surgical/anesthesia details, and Enhanced Recovery After Surgery protocol compliance elements (pre-, intra-, and postoperative phases) were entered into the Enhanced Recovery After Surgery Interactive Audit System. Surgical complexity was stratified according to the Aletti scoring system (low vs medium/high). The following covariates were accounted for in the analysis: age, body mass index, smoking status, presence of diabetes, American Society of Anesthesiologists class, International Federation of Gynecology and Obstetrics stage, preoperative chemotherapy, radiotherapy, operating time, surgical approach (open vs minimally invasive), intraoperative blood loss, hospital, and Enhanced Recovery After Surgery implementation status. The primary end points were primary hospital length of stay and complications. Negative binomial regression was used to model length of stay, and logistic regression to model complications, as a function of compliance score and covariates. Results: Patient demographics included a median age 56 years, 35.5% obese, 15% smokers, and 26.7% American Society of Anesthesiologists Class III-IV. Final diagnosis was malignant in 49% of patients. Laparotomy was used in 75.9% of cases, and the remainder minimally invasive surgery. The majority of cases (86%) were of low complexity (Aletti score ≤3). In patients with ovarian cancer, 69.5% had a medium/high complexity surgery (Aletti score 4–11). Median length of stay was 2 days in the low- and 5 days in the medium/high-complexity group. Every unit increase in Enhanced Recovery After Surgery guideline score was associated with 8% (IRR, 0.92; 95% confidence interval, 0.90–0.95; P\u3c.001) decrease in days in hospital among low-complexity, and 12% (IRR, 0.88; 95% confidence interval, 0.82–0.93; P\u3c.001) decrease among patients with medium/high-complexity scores. For every unit increase in Enhanced Recovery After Surgery guideline score, the odds of total complications were estimated to be 12% lower (P\u3c.05) among low-complexity patients. Conclusion: Audit of surgical practices demonstrates that improved compliance with Enhanced Recovery After Surgery Gynecologic/Oncology guidelines is associated with an improvement in clinical outcomes, including length of stay, highlighting the importance of Enhanced Recovery After Surgery implementation
The highly surprising behaviour of diphosphine ligands in iron-catalysed Negishi cross-coupling
Iron-catalysed cross-coupling is undergoing explosive development, but mechanistic understanding lags far behind synthetic methodology. Here, we find that the activity of iron–diphosphine pre-catalysts in the Negishi coupling of benzyl halides is strongly dependent on the diphosphine, but the ligand does not appear to be coordinated to the iron during turnover. This was determined using time-resolved in operando X-ray absorption fine structure spectroscopy employing a custom-made flow cell and confirmed by 31P NMR spectroscopy. While the diphosphine ligands tested are all able to coordinate to iron(II), in the presence of excess zinc(II)—as in the catalytic reaction—they coordinate predominantly to the zinc. Furthermore, combined synthetic and kinetic investigations implicate the formation of a putative mixed Fe–Zn(dpbz) species before the rate-limiting step of catalysis. These unexpected findings may not only impact the field of iron-catalysed Negishi cross-coupling, but potentially beyond to reactions catalysed by other transition metal/diphosphine complexes
Stem-cell competition
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/62534/1/418025a.pd
Alternate transcription of the Toll-like receptor signaling cascade
BACKGROUND: Alternate splicing of key signaling molecules in the Toll-like receptor (Tlr) cascade has been shown to dramatically alter the signaling capacity of inflammatory cells, but it is not known how common this mechanism is. We provide transcriptional evidence of widespread alternate splicing in the Toll-like receptor signaling pathway, derived from a systematic analysis of the FANTOM3 mouse data set. Functional annotation of variant proteins was assessed in light of inflammatory signaling in mouse primary macrophages, and the expression of each variant transcript was assessed by splicing arrays. RESULTS: A total of 256 variant transcripts were identified, including novel variants of Tlr4, Ticam1, Tollip, Rac1, Irak1, 2 and 4, Mapk14/p38, Atf2 and Stat1. The expression of variant transcripts was assessed using custom-designed splicing arrays. We functionally tested the expression of Tlr4 transcripts under a range of cytokine conditions via northern and quantitative real-time polymerase chain reaction. The effects of variant Mapk14/p38 protein expression on macrophage survival were demonstrated. CONCLUSION: Members of the Toll-like receptor signaling pathway are highly alternatively spliced, producing a large number of novel proteins with the potential to functionally alter inflammatory outcomes. These variants are expressed in primary mouse macrophages in response to inflammatory mediators such as interferon-γ and lipopolysaccharide. Our data suggest a surprisingly common role for variant proteins in diversification/repression of inflammatory signaling
Engineering of Niobium Surfaces Through Accelerated Neutral Atom Beam Technology For Quantum Applications
A major roadblock to scalable quantum computing is phase decoherence and
energy relaxation caused by qubits interacting with defect-related two-level
systems (TLS). Native oxides present on the surfaces of superconducting metals
used in quantum devices are acknowledged to be a source of TLS that decrease
qubit coherence times. Reducing microwave loss by surface engineering (i.e.,
replacing uncontrolled native oxide of superconducting metals with a thin,
stable surface with predictable characteristics) can be a key enabler for
pushing performance forward with devices of higher quality factor. In this
work, we present a novel approach to replace the native oxide of niobium
(typically formed in an uncontrolled fashion when its pristine surface is
exposed to air) with an engineered oxide, using a room-temperature process that
leverages Accelerated Neutral Atom Beam (ANAB) technology at 300 mm wafer
scale. This ANAB beam is composed of a mixture of argon and oxygen, with
tunable energy per atom, which is rastered across the wafer surface. The
ANAB-engineered Nb-oxide thickness was found to vary from 2 nm to 6 nm
depending on ANAB process parameters. Modeling of variable-energy XPS data
confirm thickness and compositional control of the Nb surface oxide by the ANAB
process. These results correlate well with those from transmission electron
microscopy and X-ray reflectometry. Since ANAB is broadly applicable to
material surfaces, the present study indicates its promise for modification of
the surfaces of superconducting quantum circuits to achieve longer coherence
times.Comment: 22 pages, 7 figures, will be submitted to Superconductor Science and
Technology Special Focus Issue Journa
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