Strategies for the discontinuation of humidified high flow nasal cannula (HHFNC) in preterm infants (Review)

BACKGROUND: Humidified high flow nasal cannula (HHFNC) delivers humidified gas at increased flow rates via binasal prongs and is becoming widely accepted as a method of non-invasive respiratory support for preterm infants. While indications for the use of (HHFNC) and its associated risks and benefits are being investigated, the best strategy for the discontinuation of HHFNC remains unknown. At what point an infant is considered stable enough to attempt to start withdrawing their HHFNC is not known. The criteria for a failed attempt at HHFNC discontinuation is also unclear

Competitive surfing: a physiological profile of athletes and determinants of performance

Despite a huge growth in competitive surfing there is still a paucity of research available to underpin assessment and conditioning practice. Limited research investigating surfers’ aerobic and anaerobic fitness provides an initial insight into the physiological demands of surfing; however it is limited in terms of competitive surfing and is characterized by methodological discrepancies. Likewise performance analysis has not been utilized extensively in surfing. Information available to-date suggests that competitive surfing is characterized by repeat high intensity intermittent bouts of paddling interspersed with moderate and high heart rates. Additionally, research evidence indicates that surfers possess moderately high aerobic fitness levels, comparable to other athletic groups such as competitive swimmers and surf life savers. To understand more about the sport of surfing, fundamental research into competitive surfing is needed. Therefore, the objectives of this study were to use methods of performance analysis to measure the physical outputs, workloads and activity patterns of elite surfers during competitions, and to specifically measure their anaerobic power output and peak oxygen uptake (VO2peak) on a modified kayak ergometer, and the relationship between these outputs and surfing performance. The study investigated the performance of surfing athletes during competitive surfing events. Twelve national ranked surfers were fitted with heart rate monitors and Global Positioning System (GPS) units and videoed during two sanctioned competitions. From the 32 videos analysed the greatest amount of time spent during surfing was paddling 54 ± 6.3%. Remaining stationary represented 28 ± 6.9% of the total time, wave riding and paddling for a wave represented only 8 ± 2%, and 4 ± 1.5% respectively. Surfers spent 61 ± 7% of the total paddling bouts and 64 ± 6.8% of total stationary bouts between 1 - 10 seconds. The average speed recorded via GPS for all subjects was 3.7 ± 0.6 km/h, with an average maximum speed of 33.4 ± 6.5 km/h (45 km/h was the peak). Surfers spent 58 ± 9.9% of the total speed zones between 1 – 4 km/h. The average distance covered from the two events combined was 1605 ± 313.5 meters. During the heats, surfers spent 60% of the total time between 56% and 74% of age predicted heart rate maximum (HRmax), 19% above 46% HRmax and approximately 3% above 83% HRmax. The mean HR during the surf competitions was 139.7 ± 11. b.min-1 (64.4% HRmax), with a (mean) peak of 190 ± 12. b.min-1 (87.5% HRmax). The aerobic VO2peak uptake and anaerobic peak power of nationally ranked surf athletes was determined over multiple testing occasions using a customized surf-paddle specific, kayak ergometer. Eight national level surfers participated in the incremental VO2peak test and 20 participated in the anaerobic power test. A kayak ergometer was modified with a surfboard and hand paddles, in an attempt to simulate a surfing-specific paddling action. The subjects’ peak power (W) output calculated via the kayak ergometer computer was 205 ± 54.3 W, during a 10 second maximal intensity simulated paddle. A key finding from the current study was the significant relationship between surfers season ranking and anaerobic peak power output (r= -0.55, P= 0.02). Although correlations do not imply cause and effect, such a finding provides theoretical support for the importance of anaerobic paddling power in assessment batteries and conditioning practice for surf athletes. During the incremental VO2peak uptake test, subjects recorded a VO2peak of 44.0 ± 8.26 mL/kg/min, a result similar to previous studies. We found that there was no significant correlation between the surfers’ season ranking and aerobic VO2peak values, or aerobic peak power outputs. Thus suggesting that peak oxygen uptake and peak aerobic power are not defining measures of surfing ability. In conclusion, competitive surfing involves repeated measures of low intensity paddling, followed by intermittent high intensity bouts of all out paddling intercalated with relatively short recovery periods, combined with intermittent breath holding. Paddle power is conceivably important for competitive surfing athletes due to the significant relationship between surfers’ season rank and peak anaerobic power. The ability to produce maximal power might improve surfing performance by allowing more powerful surf athletes to paddle and catch waves that lower ranked competitors miss

Scoring Analysis of the Men’s 2013 World Championship Tour of Surfing

The study compared scores obtained by the 10 highest and lowest ranked athletes on the men’s 2013 World Championship Tour (WCT) of surfing. Significant differences (p\u3c.001) were identified between the two groups’ average wave scores, average total scores and total heats competed. In addition, the average standard deviation (SD) of each surfer’s wave score was significantly different (p = .020) between the two groups. Significant moderate correlations were identified between athletes’ average placing and the SD of their wave scores (r = .596, p = .006), and total heat scores (r=.474, p=.035). Repeated measures ANOVA also revealed significant differences between heat scores obtained during the final and all previous rounds (p \u3c .001-.041). In conclusion, higher ranked surfers achieved higher wave scores and heat totals, and were more consistent in scoring. On average, a 1.04 point increase per wave score would allow a bottom 10 ranked surfer to reach the top 10, a small but impactful gain

Workloads of Competitive Surfing: Work-to-Relief Ratios, Surf-Break Demands, and Updated Analysis

The study provides an in-depth descriptive and quantitative time-motion analysis of competitive surfing, using Global PositioningSystem (GPS) units and video synchronization, which serves toextend upon the results of Farley, Harris, and Kilding (Journal ofStrength and Conditioning Research, 26, 7 [2012]). In addition,comparisons between locations and surfers competing in thesame heats were performed. Global Positioning System andvideo data were collected from 41 male competitive surfers(23.266.1 years, 71610.3 kg, 177.266.4 cm) participatingin 3 professional domestic surfing events, with competitive heatsof 20-minute duration. Fifty data sets were analyzed across the 3competitions, with velocities and distances covered, proportionof time spent performing various surfing activities, and totalwork-to-relief ratio determined. Results revealed surfers paddled44% of the total time, followed by stationary periods (42%).Surfers performed at a significantly (p#0.05) higher work-to-relief ratio (1.7:1) at the Beach-break (an exposed beach) com-pared with point-break 1 and 2 (waves breaking around a rockypoint). Point-breaks 1 and 2 had longer continuous durations ofpaddling, with significantly longer rides at point-break 1 over theBeach-break (p#0.01) and point-break 2 (p#0.01). Theaverage maximal speed (24.8 km$h21) from point-break 2 wassignificantly faster than point-break 1 (p#0.01) and Beach-break (p#0.05). This information should influence surfing drills and conditioning methods to prepare these athletes for the disparate demands, such as training for a point-break competition involving longer durations of continuous paddling and short, high-intensity workloads for a Beach-break

Assessment of F/HN-Pseudotyped Lentivirus as a Clinically Relevant Vector for Lung Gene Therapy

RATIONALE: Ongoing efforts to improve pulmonary gene transfer thereby enabling gene therapy for the treatment of lung diseases, such as cystic fibrosis (CF), has led to the assessment of a lentiviral vector (simian immunodeficiency virus [SIV]) pseudotyped with the Sendai virus envelope proteins F and HN. OBJECTIVES: To place this vector onto a translational pathway to the clinic by addressing some key milestones that have to be achieved. METHODS: F/HN-SIV transduction efficiency, duration of expression, and toxicity were assessed in mice. In addition, F/HN-SIV was assessed in differentiated human air-liquid interface cultures, primary human nasal epithelial cells, and human and sheep lung slices. MEASUREMENTS AND MAIN RESULTS: A single dose produces lung expression for the lifetime of the mouse (~2 yr). Only brief contact time is needed to achieve transduction. Repeated daily administration leads to a dose-related increase in gene expression. Repeated monthly administration to mouse lower airways is feasible without loss of gene expression. There is no evidence of chronic toxicity during a 2-year study period. F/HN-SIV leads to persistent gene expression in human differentiated airway cultures and human lung slices and transduces freshly obtained primary human airway epithelial cells. CONCLUSIONS: The data support F/HN-pseudotyped SIV as a promising vector for pulmonary gene therapy for several diseases including CF. We are now undertaking the necessary refinements to progress this vector into clinical trials

Lattice Gas Automata for Reactive Systems

Reactive lattice gas automata provide a microscopic approachto the dynamics of spatially-distributed reacting systems. After introducing the subject within the wider framework of lattice gas automata (LGA) as a microscopic approach to the phenomenology of macroscopic systems, we describe the reactive LGA in terms of a simple physical picture to show how an automaton can be constructed to capture the essentials of a reactive molecular dynamics scheme. The statistical mechanical theory of the automaton is then developed for diffusive transport and for reactive processes, and a general algorithm is presented for reactive LGA. The method is illustrated by considering applications to bistable and excitable media, oscillatory behavior in reactive systems, chemical chaos and pattern formation triggered by Turing bifurcations. The reactive lattice gas scheme is contrasted with related cellular automaton methods and the paper concludes with a discussion of future perspectives.Comment: to appear in PHYSICS REPORTS, 81 revtex pages; uuencoded gziped postscript file; figures available from [email protected] or [email protected]

Racial/ethnic and sexual behavior disparities in rates of sexually transmitted infections, San Francisco, 1999-2008

<p>Abstract</p> <p>Background</p> <p>Racial/ethnic minorities and men who have sex with men (MSM) represent populations with disparate sexually transmitted infection (STI) rates. While race-specific STI rates have been widely reported, STI rates among MSM is often challenging given the absence of MSM population estimates. We evaluated the race-specific rates of chlamydia and gonorrhea among MSM and non-MSM in San Francisco between 1999-2008.</p> <p>Methods</p> <p>2000 US Census data for San Francisco was used to estimate the number of African-American, Asian/Pacific Islander, Hispanic, and white males. Data from National HIV Behavioral Surveillance (NHBS) MSM 1, conducted in 2004, was used to estimate the total number of MSM in San Francisco and the size of race/ethnic sub-populations of MSM. Non-MSM estimates were calculated by subtracting the number of estimated MSM from the total number of males residing in San Francisco. Rates of MSM and non-MSM gonorrhea and chlamydia reported between 1999 and 2008 were stratified by race/ethnicity. Ratios of MSM and non-MSM rates of morbidity were calculated by race/ethnicity.</p> <p>Results</p> <p>Between 1999-2008, MSM accounted for 72% of gonorrhea cases and 51% of chlamydia cases. Throughout the study period, African-American MSM had the highest chlamydia rate with 606 cases per 100,000 in 1999 increasing to 2067 cases per 100,000 in 2008. Asian/Pacific Islander MSM consistently had the lowest rate among MSM with1003 cases per 100,000 in 2008. The ratio of MSM/non-MSM for chlamydia was highest among whites 11.6 (95% CI: 8.8-14.4) and Asian/Pacific Islanders 8.6 (95% CI: 6.2-11), and lowest among African-Americans 1.53 (95% CI: 1.2-1.9) and Hispanics 4.43 (95% CI: 2.8-6.0). Gonorrhea rates were similar for African-American, white, and Hispanic MSM between 2137-2441 cases per 100,000 in 2008. Asian/Pacific Islander MSM had the lowest gonorrhea rate with 865 cases per 100,000 in 2008. The ratio of MSM/non-MSM for gonorrhea was highest among whites 11.6 (95% CI: 8.8-14.4) and Asian/Pacific Islanders 8.6 (95% CI: 6.2-11), and lowest among African-Americans 1.53 (95% CI: 1.2-1.9) and Hispanics 4.43 (95% CI: 2.8-6.0).</p> <p>Conclusions</p> <p>For all racial/ethnic groups in San Francisco, MSM carried a substantially higher burden of STIs compared to non-MSM except among African-American men. These racial and sexual behavior disparities warrant further public health attention and resources.</p

Dusty Planetary Systems

Extensive photometric stellar surveys show that many main sequence stars show emission at infrared and longer wavelengths that is in excess of the stellar photosphere; this emission is thought to arise from circumstellar dust. The presence of dust disks is confirmed by spatially resolved imaging at infrared to millimeter wavelengths (tracing the dust thermal emission), and at optical to near infrared wavelengths (tracing the dust scattered light). Because the expected lifetime of these dust particles is much shorter than the age of the stars (>10 Myr), it is inferred that this solid material not primordial, i.e. the remaining from the placental cloud of gas and dust where the star was born, but instead is replenished by dust-producing planetesimals. These planetesimals are analogous to the asteroids, comets and Kuiper Belt objects (KBOs) in our Solar system that produce the interplanetary dust that gives rise to the zodiacal light (tracing the inner component of the Solar system debris disk). The presence of these "debris disks" around stars with a wide range of masses, luminosities, and metallicities, with and without binary companions, is evidence that planetesimal formation is a robust process that can take place under a wide range of conditions. This chapter is divided in two parts. Part I discusses how the study of the Solar system debris disk and the study of debris disks around other stars can help us learn about the formation, evolution and diversity of planetary systems by shedding light on the frequency and timing of planetesimal formation, the location and physical properties of the planetesimals, the presence of long-period planets, and the dynamical and collisional evolution of the system. Part II reviews the physical processes that affect dust particles in the gas-free environment of a debris disk and their effect on the dust particle size and spatial distribution.Comment: 68 pages, 25 figures. To be published in "Solar and Planetary Systems" (P. Kalas and L. French, Eds.), Volume 3 of the series "Planets, Stars and Stellar Systems" (T.D. Oswalt, Editor-in-chief), Springer 201

The role of doxorubicin in non-viral gene transfer in the lung

a b s t r a c t Proteasome inhibitors have been shown to increase adeno-associated virus (AAV)-mediated transduction in vitro and in vivo. To assess if proteasome inhibitors also increase lipid-mediated gene transfer with relevance to cystic fibrosis (CF), we first assessed the effects of doxorubicin and N-acetyl-L-leucinyl-L-leucinal-L-norleucinal in non-CF (A549) and CF (CFTE29o-) airway epithelial cell lines. CFTE29o-cells did not show a response to Dox or LLnL; however, gene transfer in A549 cells increased in a dose-related fashion (p &lt; 0.05), up to approximately 20-fold respectively at the optimal dose (no treatment: 9.3 Â 10 4 AE 1.5 Â 10 3 , Dox: 1.6 Â 10 6 AE 2.6 Â 10 5 , LLnL: 1.9 Â 10 6 AE 3.2 Â 10 5 RLU/mg protein). As Dox is used clinically in cancer chemotherapy we next assessed the effect of this drug on non-viral lung gene transfer in vivo. CF knockout mice were injected intraperitoneally (IP) with Dox (25-100 mg/kg) immediately before nebulisation with plasmid DNA carrying a luciferase reporter gene under the control of a CMV promoter/ enhancer (pCIKLux) complexed to the cationic lipid GL67A. Dox also significantly (p &lt; 0.05) increased expression of a plasmid regulated by an elongation factor 1a promoter (hCEFI) approximately 8-fold. Although administration of Dox before lung gene transfer may not be a clinically viable option, understanding how Dox increases lung gene expression may help to shed light on intracellular bottle-necks to gene transfer, and may help to identify other adjuncts that may be more appropriate for use in man

Ecosystem services and the idea of shared values

Ecosystem services conceptualise the diverse values that ecosystems provide to humanity. This was recognised in the United Kingdom's National Ecosystem Assessment, which noted that appreciation of the full value of ecosystem services requires recognition of values that are shared. By operationalising the shared values concept, it is argued that the contribution of ecosystem services to human well-being can be represented more holistically. This paper considers current understanding of shared values and develops a new metanarrative of shared values beyond the aggregated utilities of individuals. This metanarrative seeks to conceptualise how values can be held both individually and communally, and what this means for identifying their scale and means of enumeration. The paper poses a new reading of the idea of shared values that reconciles the elicitation of preformed individual values with the formation and expression of shared social values. The implication is that shared values need to be conceived as normative constructs that are derived through social processes of value formation and expression. Shared values thus do not necessarily exist a priori; they can be deliberated through formal and informal processes through which individuals can separate their own preferences from a broader metanarrative about what values ought to be shared