The impact of 48 h high carbohydrate diets with high and low FODMAP content on gastrointestinal status and symptoms in response to endurance exercise, and subsequent endurance performance

This study investigated the effects of a high carbohydrate diet, with varied fermentable oligo-, di-, and mono-saccharide and polyol (FODMAP) content, before endurance exercise on gastrointestinal integrity, motility, and symptoms; and subsequent exercise performance. Twelve endurance athletes were provided with a 48 h high carbohydrate (mean ± SD: 12.1 ± 1.8 g kg day-1) diet on two separate occasions, composed of high (54.8 ± 10.5 g day-1) and low FODMAP (3.0 ± 0.2 g day-1) content. Thereafter, participants completed a 2 h steady-state running exercise at 60% of V ˙ O 2 max (22.9 ± 1.2 °C, 46.4 ± 7.9% RH), followed by a 1 h distance performance test. Pre-exercise and every 20 min during steady-state exercise, 100 mL maltodextrin (10% w/v) solution was consumed. A 150 mL lactulose (20 g) solution was consumed 30 min into the distance performance test to determine orocecal transit time (OCTT) during exercise. Blood was collected pre- and post exercise to determine gastrointestinal integrity biomarkers (i.e., I-FABP, sCD14, and CRP). Breath hydrogen (H2) and gastrointestinal symptoms (GIS) were determined pre-exercise, every 15 min, during and throughout recovery. No differences in gastrointestinal integrity biomarkers, OCTT, or distance completed were observed between trials. Pre-exercise total-GIS (1.3 ± 2.9 vs. 4.3 ± 4.4), gut discomfort (9.9 ± 8.1 vs. 15.8 ± 9.0), and upper-GIS (2.8 ± 2.6 vs. 5.7 ± 4.8) during exercise were less severe on high carbohydrate low FODMAP (HC-LFOD) versus high carbohydrate high FODMAP (HC-HFOD) (p < 0.05). Gut discomfort (3.4 ± 4.4 vs. 0.2 ± 0.6) and total-GIS (4.9 ± 6.8 vs. 0.2 ± 0.6) were higher during recovery on HC-LFOD versus HC-HFOD (p < 0.05). The FODMAP content of a 48 h high carbohydrate diet does not impact gastrointestinal integrity or motility in response to endurance exercise. However, a high FODMAP content exacerbates GIS before and during exercise, but this does not impact performance outcomes.

Best practice recommendations for body composition considerations in sport to reduce health and performance risks: a critical review, original survey and expert opinion by a subgroup of the IOC consensus on Relative Energy Deficiency in Sport (REDs)

BACKGROUND

The assessment of body composition (BC) in sport raises concern for athlete health, especially where an overfocus on being lighter or leaner increases the risk of Relative Energy Deficiency in Sport (REDs) and disordered eating.

METHODS

We undertook a critical review of the effect of BC on performance (29 longitudinal, prospective or intervention studies) and explored current practice related to BC considerations via a follow-up to a 2013 internationally distributed survey.

RESULTS

The review found that a higher level of body fat was negatively associated with endurance performance, while a gain in muscle mass resulted in performance benefits across sports. BC did not contribute to early talent identification, and no unique cut-off to signify a performance advantage for BC was identified. BC appears to be one of an array of variables impacting performance, and its influence should not be overstated. The survey (125 practitioners, 61 sports and 26 countries) showed subtle changes in BC considerations over time, such as an increased role for sport dietitian/nutrition practitioners as BC measurers (2013: 54%, 2022: 78%); less emphasis on reporting of body fat percentage (2013: 68%, 2022: 46%) and reduced frequency of BC assessment if ≥every fourth week (2013: 18%, 2022: 5%). Respondents remained concerned about a problematic focus on BC (2013: 69%, 2022: 78%). To address these findings, we provide detailed recommendations for BC considerations, including an overview of preferable BC methodology.

CONCLUSIONS

The 'best practice' guidelines stress the importance of a multidisciplinary athlete health and performance team, and the treatment of BC data as confidential medical information. The guidelines provide a health focus around BC, aiming to reduce the associated burden of disordered eating, problematic low energy availability and REDs.

The effect of percentage of ideal body weight on outcomes in ileo-anal pull through for ulcerative colitis

PURPOSE

Ileo-anal pull through (IAPT) is a commonly performed operation for the surgical management of ulcerative colitis. The effect of body weight on outcomes for patients undergoing this operation has not been extensively studied.

METHODS

This was a prospective cohort study at a single tertiary care inflammatory bowel disease (IBD) center. A total of 457 patients who were operated on at the Mount Sinai Medical Center between 1983 and 2015 were included. Demographic characteristics, the patients' body weight at the time of IAPT, and postoperative outcome data were collected.

RESULTS

For each patient, body weight was calculated as a percentage of the ideal body weight (IBW) for that patient's height. The mean percentage of ideal body weight was 93.9% with a standard deviation of 20%. The range for the population was 53.1 to 175%. Four hundred forty (96%) of the patients had a weight within two standard deviations of the mean, indicating a normal distribution. Seventy-nine patients developed a Clavien-Dindo class III complication necessitating a procedural treatment. The most common of these was a stricture at the anastomotic site (n = 54). Our study identified an association between a percentage of ideal body weight in the lowest quartile of our population and development of an anastomotic stricture. This association was statistically significant on multivariate analysis.

CONCLUSION

Low body weight at the time of ileo-anal pull through for treatment of UC may be a risk factor for development of anastomotic stricture requiring dilation.

Reliability of resting metabolic rate between and within day measurements using the Vyntus CPX system and comparison against predictive formulas

Background: To detect longitudinal changes of resting metabolic rate (RMR) resulting from the effects of energetic stress, reliable RMR measurements are crucial. The Vyntus CPX is a new automated indirect calorimetry system for which RMR reliability has not been determined. Additionally, its agreement with common predictive RMR formulas is unknown. Aim: To determine the within and between-day reliability of RMR measurements using the Vyntus CPX system and its agreement with predictive RMR formulas. Methods: Young (31  ±  7 years) healthy participants (n = 26, 12 females, 14 males) completed three measurements of RMR, two consecutive measures on the same day, one the day before/after, all under standardised conditions. Reliability was assessed with pairwise comparisons of between-day at the same time (BDST), within day consecutive measurements (WDCM) and between-day different time (BDDT), for parameters of reliability (mean change (MC), intraclass correlation (ICC) and typical error of measurement (TEM)). Measured RMR values (kcal/day) were compared against predictive values of 4 common formulas. Results: Parameters of reliability (mean, (95% confidence interval)) were: -BDST: MC, 0.2(-2.3-2.7)% (p = 0.67); ICC, 0.92(0.84-0.97); TEM, 4.5(3.5-6.2)%. -WDCM: MC, -2.5(-6.2-1.3)% (p = 0.21); ICC, 0.88(0.74-0.88); TEM, 7.0(5.4-9.8)%. -BDDT: MC, -1.5(-4.8-1.9)% (p = 0.57); ICC, 0.90(0.76-0.95); TEM, 6.1(4.8-8.5)%. RMR_ratios (measured/predicted) were: 1.04  ±  0.14 (Nelson, p = 0.13), 1.03  ±  0.10 (Mifflin, p = 0.21), 0.98  ±  0.09 (Harris-benedict, p = 0.30), 0.95  ±  0.11 (Cunningham₁₉₈₀, p = 0.01), 1.00  ±  0.12 (Cunningham₁₉₉₁, p = 0.90) and 0.96  ±  0.13 (DXA, p = 0.03). Conclusions: The Vyntus CPX is reliable and measured RMR values agreed with four predictive formulas but are lower than Cunningham₁₉₈₀ and DXA RMR estimates for this population.

Dietary Intake and Body Composition During Ramadan in Athletes: A Systematic Review and Meta-Analysis With Meta-Regression

The aim of this research was to evaluate the effect of Ramadan observance on dietary intake and body composition in adult athletes. This was a systematic review and meta-analysis. Data sources used were PubMed, Web of Science, Scopus, and Taylor and Francis. Eligibility criteria for selecting studies were as follows: single-group, pre-/post-Ramadan, with or without control group, conducted in athletes aged ≥19 years training at least twice a week, and published in any language before August 25, 2021. Studies assessing dietary intake and/or body composition were deemed eligible. The methodological quality of studies was assessed using QualSyst. Nine studies evaluated dietary intake; 4 of these were rated as strong quality and the remaining as moderate. Of the 17 selected studies evaluating body composition, 7 were of strong quality and the remaining 10 were rated as moderate. Compared to pre-Ramadan, energy (number of studies, K = 7; number of participants, N = 78; g = -0.781; 95% confidence interval [CI], -1.416 to -0.145; p = 0.016), carbohydrate (K = 5; N = 50; g = -1.643; 95% CI, -2.949 to -0.336; p = 0.014), and water (K = 4; N = 39; g = -1.081; 95% CI, -1.371 to -0.790; p = 0.000) intakes decreased during Ramadan. However, fat (K = 5; N = 50; g = -0.472; 95% CI, -1.085 to 0.140; p = 0.131) and protein (K = 5; N = 60; g = -0.574; 95% CI, -1.213 to -0.066; p = 0.079) intakes remained unchanged. Compared to pre-Ramadan, body mass (K = 16; N = 131; g = -0.262; 95% CI, -0.427 to -0.097; p = 0.002) and body fat percentage (K = 8; N = 81; g = -0.197; 95% CI, -0.355 to -0.040; p = 0.014) decreased in the fourth week of Ramadan. Lean body mass did not change during Ramadan (K = 4; N = 45; g = -0.047; 95% CI, -0.257 to 0.162; p = 0.658). Carbohydrate and total water intake decreased with the observance of Ramadan, but fat and protein intake were unchanged. Continued training of athletes during Ramadan was associated with a decreased body mass and body fat percentage, but not lean body mass, toward the end of the fasting month. Key pointsRamadan fasting decreases body mass and body fat percentage of athletes, but not lean body mass.Longer durations of fasting could provoke more pronounced decrements in body mass.Carbohydrate and total water intake decreased during Ramadan in athletes.Future studies, with greater methodological rigor, are required to better discern changes in dietary intake and body composition during Ramadan. Supplemental data for this article is available online at https://doi.org/10.1080/07315724.2021.2000902 .

Carbohydrate knowledge, beliefs, and intended practices, of endurance athletes who report exercise-associated gastrointestinal symptoms

This study aimed to explore carbohydrate (CHO) knowledge, beliefs, and intended practices of endurance athletes who experience exercise-associated gastrointestinal symptoms (Ex-GIS) compared to those without Ex-GIS. A validated online questionnaire was completed by endurance athletes (n = 201) participating in >60 min of exercise that present with Ex-GIS (n = 137) or without (n = 64). Descriptive statistics were used for parametric and non-parametric data with appropriate significance tests. Associations between categorical data were assessed by Chi-square analysis, and post-hoc Bonferroni tests were applied when significant. A content analysis of open-ended responses was grouped into themes, and quantitative statistics were applied. Participants included runners (n = 114, 57%), triathletes (n = 43, 21%) and non-running sports (n = 44, 21%) who participate in recreational competitive (n = 74, 37%), recreational non-competitive (n = 64, 32%), or competitive regional, national, or international levels (n = 63, 31%). Athletes correctly categorized CHO (x̄ = 92-95%) and non-CHO (x̄ = 88-90%) food and drink sources. On a Likert scale of 1 (strongly disagree) to 5 (strongly agree) athletes typically agree or strongly agree that consuming CHO around key training sessions and competitions enhances athletic performance [median = 4 (IQR, 4-5)], and they intend to consume more CHO around exercise [median = 3 (IQR, 2-3)]. No differences in beliefs and intentions were found among athletes with or without Ex-GIS. To enhance athletic performance, most endurance athletes intend to consume more CHO around exercise. Adequate knowledge of CHO-containing food sources was apparent; however, specific CHO ingestion practices remain to be verified.

An exploratory study of the management strategies reported by endurance athletes with exercise-associated gastrointestinal symptoms

This exploratory study investigated endurance athletes self-reported exercise-associated gastrointestinal symptoms (Ex-GIS) and associated strategies to manage symptomology. Adult endurance athletes with a history of Ex-GIS (n = 137) participating in events ≥ 60 min completed an online validated questionnaire. Respondents included runners (55%, n = 75), triathletes (22%, n = 30), and non-running sports (23%, n = 32), participating at a recreationally competitive (37%, n = 51), recreationally non-competitive (32%, n = 44), and competitive regional/national/international (31%, n = 42) levels. Athletes identified when Ex-GIS developed most frequently either around training (AT), around competitions (AC), or equally around both training (ET) and competitions (EC). Athletes reported the severity of each symptom before, during, and after exercise. Athletes predominantly categorized Ex-GIS severity as mild (< 5/10) on a 0 (no symptoms) to 10 (extremely severe symptoms) visual analog symptomology scale. The Friedman test and post hoc analysis with Wilcoxon signed rank test was conducted with a Bonferroni correction applied to determine differences between repeated measures. The only severe symptom of significance was the urge to defecate during training in the ET group (Z = –0.536, p = 0.01). Ex-GIS incidence was significantly higher during training and competitions in all categories. A content review of self-reported strategies (n = 277) to reduce Ex-GIS indicated popular dietary strategies were dietary fiber reduction (15.2%, n = 42), dairy avoidance (5.8%, n = 16), and a low fermentable oligosaccharides, monosaccharides, and polyols (FODMAP) diet (5.4%, n = 15). In contrast, non-dietary strategies included the use of medications (4.7%, n = 13) and relaxation/meditation (4.0%, n = 11). On a Likert scale of 1–5, the most successful dietary strategies implemented were dietary fiber reduction (median = 4, IQR = 4, 5), low FODMAP diets (median = 4, IQR = 4, 5), dairy-free diets (median = 4, IQR = 4, 5), and increasing carbohydrates (median = 4, IQR = 3, 4). Accredited practicing dietitians were rated as the most important sources of information for Ex-GIS management (n = 29). Endurance athletes use a variety of strategies to manage their Ex-GIS, with dietary manipulation being the most common.

Precision of the GE Lunar Total Body-Less Head Scan for the Measurement of Three-Compartment Body Composition in Athletes

INTRODUCTION

Dual energy X-ray absorptiometry (DXA) is widely used for the assessment of lean mass (LM), fat mass (FM) and bone mineral content (BMC). When observing standardised protocols, DXA has a high level of precision for the assessment of total body composition, including the head region. However, including the head region may have limited relevance in athletes and can be problematic when positioning taller athletes who exceed scan boundaries. This study investigated the precision of a new total-body-less-head (TBLH) DXA scan for three-compartment body composition measurement in athletes, with outcomes compared to the standard total-body DXA scan.

METHODS

Precision errors were calculated from two consecutive scans with re-positioning (Lunar iDXA, GE Healthcare, Madison, WI), in male and female athletes from a range of sports. TBLH precision was determined from repeat scans in 95 athletes (male n = 55; female n = 40; age: 26.0 ± 8.5 y; body mass: 81.2 ± 20.5 kg; stature: 1.77 ± 0.11 m), and standard total-body scan precision was derived from a sub-sample of 58 athletes (male n = 19; female n = 39; age: 27.6 ± 9.9 y; body mass: 69.6 ± 14.8 kg; stature: 1.72 ± 0.94 m). Data from the sub-sample were also used to compare precision error and 3-compartment body composition outcomes between the standard total-body scan and the TBLH scan.

RESULTS

TBLH precision errors [root mean squared-standard deviation, RMS-SD (coefficient of variation, %CV)] were bone mineral content (BMC): 15.6 g (0.5%), lean mass (LM): 254.3 g (0.4%) and fat mass (FM): 199.4 g (1.3%). These outcomes compared favourably to the precision errors derived from the standard total-body scan [BMC: 12.4 g (0.4%), LM: 202.2 g (0.4%), and FM: 160.8 g (1.1%)]. The TBLH scan resulted in lower BMC (-19.5%), LM (-6.6%), and FM (-4.5%) compared to the total-body scan (BMC: 2,308 vs. 2,865 g; LM: 46,954 vs. 50,276 g; FM: 15,183 vs. 15,888 g, all p&lt;0.005). ConclusionThe TBLH scan demonstrates high in-vivo precision comparable to that of the standard total-body scan in a heterogeneous cohort of athletes. Given the impact of head exclusion on total body composition outcomes, TBLH scans should not be used interchangeably with the standard total-body scan.

Determinants of Food Choice in Athletes: A Systematic Scoping Review

Background

The individual determinants of food choice have been extensively investigated in the general population, but there have been limited studies in athletes. A better understanding of the food making decisions can help to target interventions that lead to optimal intake for athletes’ health and performance. A scoping review will provide an understanding of the sports and settings that have been investigated, the methods and approaches to assessing food choice, as well as the factors influencing food choice.

Objective

The objective of this review was to map the available evidence on the multi-faceted determinants of food choice in athletes and describe key influences impacting their choices.

Eligibility criteria.

Athletes 16 years and over from any country who engage in physical activity with the intent to be competitive. Studies were included if they reported the multi-faceted determinants of food choice as either a primary or secondary outcome. All study designs were considered.

Sources of Evidence.

This review followed the PRISMA extension for Scoping Reviews. Eleven databases including PubMed, Web of Science (Clarivate Analytics), SPORTDiscus (EBSCO), PsycNET (APA), Health Collection (Informit), CINAHL (EBSCO), the Cochrane Library, ProQuest Dissertations and Theses Global, Trove (National Library of Australia), JBI (Ovid), and Google scholar were searched between September–November 2020 and updated in March 2021.

Charting of Data

Search results were screened with selected studies extracted into a summary table established a priori by the authors. Study quality was assessed using standardised reporting tools for qualitative and quantitative research designs. The scope and quality of evidence was summarised and reported.

Results

A total of 15 studies were included. Qualitative research included one research thesis and six primary research studies using both focus groups and semi-structured interviews. Quantitative research included one research thesis and seven primary research studies with cross-sectional design using different validated and non-validated survey instruments. No longitudinal or intervention studies were found. The majority of studies have been published since 2018 and conducted across multiple countries with either mixed cohorts of athletes or focused on predominately endurance or team sports. The quality of reporting was variable, particularly for qualitative research. Outcomes suggested that performance and health were relevant to athlete food choice, with varying impact of competition season, the level of experience, the culture of the sport, the cultural background or nationality of the athlete, athlete sex and the food environment.

Conclusion

More research is needed on the multi-faceted determinants of food choice in different cohorts of athletes, particularly females. Future research could explore the relationship between food choice, nutrition knowledge and diet quality or the change in food choice across the phase of the seasons and through injury and illness. Use of validated measurement tools and robust reporting will enable critical interpretation of the study methods and outcomes for use in practice.

Registration OSF Registries: Open-ended registration 25th Sept 2020 https://doi.org/10.17605/OSF.IO/4PX2A

Development and validation of a questionnaire investigating endurance athletes practices to manage gastrointestinal symptoms around exercise

AIM

To develop and validate a questionnaire investigating endurance athletes' carbohydrate beliefs, knowledge, information sources, and other dietary and non-dietary practices related to exercise-associated gastrointestinal symptoms.

METHODS

A questionnaire was developed by a review of relevant literature and sports-related questionnaires, and input from five experienced sports dietitians. Item construct and format was adapted and modified from a previous questionnaire. The modified questionnaire sought information on demographics, nutrition knowledge, beliefs, intended practices, information sources and exercise-associated gastrointestinal symptoms. A five-phase validity process was conducted to determine content, face and construct validity, item difficulty and internal reliability of the questionnaire. The Delphi technique was applied with experts over three anonymous rounds. Items were reviewed to determine whether to keep, modify, or delete, rate the relevance of each item using a content validity index (CVI), and provide comments. A content analysis was conducted on all comments after each round. Online interviews were conducted with a pilot group of endurance athletes (n = 15) to assess item difficulty and feasibility. Nutrition knowledge was compared between pilot group of athletes and experts to determine construct validity and internal consistency. A test-retest process was applied to a second pilot group (n = 8) to verify questionnaire reliability.

RESULTS

High CVI (≥.83) and agreement scores were obtained through the Delphi technique. High reliability (r = .942) and acceptable internal consistency (α = .53-.78) of the questionnaire were obtained.

CONCLUSIONS

The questionnaire was shown to be a valid and reliable tool that will be of use for clinicians and research purposes.

Protein Requirements of Pre-Menopausal Female Athletes: Systematic Literature Review

This systematic literature review aimed to determine the protein requirements of pre-menopausal (e.g., 18-45 years) female athletes and identify if the menstrual cycle phase and/or hormonal contraceptive use influence protein requirements. Four databases were searched for original research containing pre-menopausal female athletes that ingested protein alongside exercise. The Academy of Nutrition and Dietetics Quality Criteria Checklist was used to determine study quality. Fourteen studies, which included 204 recreationally active or competitive females, met the eligibility criteria for inclusion in this review, and all were assessed as positive quality. The estimated average requirement (EAR) for protein intake of pre-menopausal recreational and/or competitive female athletes is similar for those undertaking aerobic endurance (1.28-1.63 g/kg/day), resistance (1.49 g/kg/day) and intermittent exercise (1.41 g/kg/day) of ~60-90 min duration. The optimal acute protein intake and influence of menstrual cycle phase or hormonal contraceptive use on protein requirements could not be determined. However, pre- and post-exercise protein intakes of 0.32-0.38 g/kg have demonstrated beneficial physiological responses in recreational and competitive female athletes completing resistance and intermittent exercise. The protein requirements outlined in this review can be used for planning and assessing protein intakes of recreational and competitive pre-menopausal female athletes.

Client experiences and confidence in nutrition advice delivered by registered exercise professionals

OBJECTIVES

The aims of this cross-sectional study were to describe the client experiences of registered exercise professionals (REP) in regard to nutrition advice, and to identify factors considered important when selecting a REP.

DESIGN

A convenience sample of fitness facility-users were recruited. Participants completed a 46 item online questionnaire.

METHOD

Frequency distributions were calculated for nutrition advice received from a REP, confidence in the nutrition advice received, and factors considered when selecting a REP. The effect of sex and level of education on participant responses were investigated.

RESULTS

A total of 455 individuals participated, of which 55.6% had worked with a REP. Participants working with a REP had received nutrition advice on body fat loss (77.4%), muscle gain (78.7%), and clinical nutrition (51.9%). Sex and level of education did not influence confidence in nutrition advice, with 60.7% of participants reporting being 'very or extremely confident' in the nutrition advice. Over half of participants (58.3%) prefer to work with a REP who offers nutrition advice. Basic and personal professional conduct were identified as 'very or extremely important' by >70% of participants when selecting a REP.

CONCLUSION

Clients of REP prefer to work with a REP who provides nutrition advice and are generally confident in this advice. Educating fitness facility-users on the nutrition scope of practice of REP and promoting the role of accredited nutrition professionals should be advocated. Encouraging REP to work collaboratively with nutrition professionals will help ensure clients receive appropriate nutrition care, while better allowing REP to remain within their scope of practice.

Origin of Groundwater Arsenic in a Rural Pleistocene Aquifer in Bangladesh Depressurized by Distal Municipal Pumping

Across South Asia, millions of villagers have reduced their exposure to high-arsenic (As) groundwater by switching to low-As wells. Isotopic tracers and flow modeling are used in this study to understand the groundwater flow system of a semi-confined aquifer of Pleistocene (>10 kyr) age in Bangladesh that is generally low in As but has been perturbed by massive pumping at a distance of about 25 km for the municipal water supply of Dhaka. A 10- to 15-m-thick clay aquitard caps much of the intermediate aquifer (>40- to 90-m depth) in the 3-km² study area, with some interruptions by younger channel sand deposits indicative of river scouring. Hydraulic heads in the intermediate aquifer below the clay-capped areas are 1-2 m lower than in the high-As shallow aquifer above the clay layer. In contrast, similar heads in the shallow and intermediate aquifer are observed where the clay layer is missing. The head distribution suggests a pattern of downward flow through interruptions in the aquitard and lateral advection from the sandy areas to the confined portion of the aquifer. The interpreted flow system is consistent with ³H-³He ages, stable isotope data, and groundwater flow modeling. Lateral flow could explain an association of elevated As with high methane concentrations within layers of gray sand below certain clay-capped portions of the Pleistocene aquifer. An influx of dissolved organic carbon from the clay layer itself leading to a reduction of initially orange sands has also likely contributed to the rise of As.

Sports nutrition for the recreational athlete

BACKGROUND

Recreational sports participation provides many potential health benefits. However, some athletes experience medical problems associated with, or exacerbated by, a mismanagement of the relationship between their diet and sporting endeavours.

OBJECTIVE

The aim of this article is to highlight recent developments in clinical sports nutrition, with a focus on providing evidence-based advice and resources for the management of common medical presentations.

DISCUSSION

A low dietary energy intake relative to exercise energy demands (ie low energy availability) may result in an array of medical issues. An evidence-based framework for advice on sports supplements is available.

Disordered eating behaviours in female physique athletes

Despite substantial growth in participation rates in physique sports, little is known about the modern day female physique athlete. The extreme physique traits of successful female physique athletes suggest this population may be particularly at risk of developing disordered eating (DE). The aim of this study was to determine if female physique athletes across the main divisions of bikini, fitness, figure and bodybuilding were at risk of DE and to explore possible associated risk factors. Furthermore, we aimed to investigate differences in incidence of DE across divisions given differences in physique requirements. Female physique athletes (n = 348) were recruited using targeted methods and completed an online survey based on validated questionnaires, including the Drive for Thinness, Body Dissatisfaction, and Bulimia subscales of the Eating Disorder Inventory (EDI), Pathogenic Weight Control Measures (PWCM), and the Cognitive Dietary Restraint subscale of the Three-Factor Eating Questionnaire (TFEQ-CDR). Athletes scoring above the cut off values for one or more of the EDI subscales or engaged in at least one of the most concerning PWCM (binge eating, laxative use, and self-induced vomiting) were considered at risk of DE. Approximately half of the participants were identified with DE (46.6%), independent of division, with 27.3% exhibiting clinical and 19.3% having subclinical DE. Furthermore, approximately half (48.9%) of participants engaged in at least one of the most concerning PWCM within the past three months, with a smaller proportion (5.2%) engaging in all three PWCM. Weak but significant correlations were found between some EDI subscales and reason for sport participation, BMI and body composition goals. Drive for thinness and body dissatisfaction were positively associated with use of PWCM. In conclusion, a high proportion of female physique athletes were identified with DE, with a concerning number of athletes engaging in harmful PWCM.

Body composition of elite Olympic combat sport athletes

Physique traits of a range of elite athletes have been identified; however, few detailed investigations of Olympic combat sports (judo, wrestling, taekwondo and boxing) exist. This is surprising given the importance of body composition in weight category sports. We sought to develop a descriptive database of Olympic combat sport athletes, compare variables relative to weight division and examine differences within and between sports. Additionally, we investigated the appropriateness of athletes' self-selected weight classes compared to an internationally recognised classification system (the NCAA minimum wrestling weight scheme used to identify minimum 'safe' weight). Olympic combat sport athletes (56♂, 38♀) had body mass (BM), stretch stature and dual-energy X-ray absorptiometry derived body composition assessed within 7-21 days of competition. Most athletes were heavier than their weight division. Sport had an effect (p < .05) on several physique traits, including; lean mass, lean mass distribution, stretch stature and BMI. BM was strongly positively correlated (r > 0.6) with; fat free mass, fat mass and body fat percentage, however, was not predictive of total mass/weight division. The Olympic combat sports differ in competitive format and physiological requirements, which is partly reflected in athletes' physique traits. We provide reference ranges for lean and fat mass across a range of BM. Lighter athletes likely must utilise acute weight loss in order to make weight, whereas heavier athletes can potentially reduce fat mass.

Interpretation of Dual-Energy X-Ray Absorptiometry-Derived Body Composition Change in Athletes: A Review and Recommendations for Best Practice

Dual-energy X-ray absorptiometry (DXA) is a medical imaging device which has become the method of choice for the measurement of body composition in athletes. The objectives of this review were to evaluate published longitudinal DXA body composition studies in athletic populations for interpretation of "meaningful" change, and to propose a best practice measurement protocol. An online search of PubMed and CINAHL via EBSCO Host and Web of Science enabled the identification of studies published until November 2016. Those that met the inclusion criteria were reviewed independently by 2 authors according to their methodological quality and interpretation of body composition change. Twenty-five studies published between 1996 and November 2016 were reviewed (male athletes: 13, female athletes: 3, mixed: 9) and sample sizes ranged from n = 1 to 212. The same number of eligible studies was published between 2013 and 2016, as over the 16 yr prior (between 1996 and 2012). Seven did not include precision error, and fewer than half provided athlete-specific precision error. There were shortfalls in the sample sizes on which precision estimates were based and inconsistencies in the level of pre-scan standardization, with some reporting full standardization protocols and others reporting only single (e.g., overnight fast) or no control measures. There is a need for standardized practice and reporting in athletic populations for the longitudinal measurement of body composition using DXA. Based on this review and those of others, plus the official position of the International Society for Clinical Densitometry, our recommendations and protocol are proposed as a guide to support best practice.

Physiological implications of preparing for a natural male bodybuilding competition

This study aimed to describe the body composition and physiological changes which take place during the in-season and recovery periods of a group of natural bodybuilders. Natural male bodybuilders (n = 9) were assessed 16 (PRE16), 8 (PRE8), and 1 (PRE1) week(s) before, and 4 (POST4) weeks after a bodybuilding competition. Assessments included body composition, resting metabolic rate (RMR), serum hormones, and 7-day weighed food and training diaries. Change in parameters was assessed using repeated-measures analysis of variance. Dietary protein intake remained high throughout the study period (2.8-3.1 g kg^-1 d^-1). Fat mass (FM) was significantly reduced from PRE16 to PRE1 (8.8 ± 3.1 vs. 5.3 ± 2.4 kg, P < .01). There was a small decrease in lean mass (LM) from PRE8 to PRE1 (71.8 ± 9.1 vs. 70.9 ± 9.1 kg, P < .05). No changes in RMR were observed (P > .05). Large reductions in total and free testosterone (16.4 ± 4.4 vs. 10.1 ± 3.6 nmol L^-1, P < .05; 229.3 ± 72.4 vs. 116.8 ± 76.9 pmol L^-1, P < .05), and insulin-like growth factor-1 (IGF-1) (27.0 ± 7.7 vs. 19.9 ± 7.6 nmol L^-1, P < .05) occurred between PRE16 and PRE1. LM and IGF-1 increased from PRE1 to POST4 (70.9 ± 9.1 vs. 72.5 ± 8.5 kg, P < .05; 19.9 ± 7.6 vs. 25.4 ± 9.3 nmol L^-1, P < .05). Despite substantial reductions in FM, participants maintained almost all of their LM. The reduction in anabolic hormone concentration is likely attributable to the prolonged negative energy balance, despite a high dietary protein intake.

A randomised controlled intervention study investigating the efficacy of carotenoid-rich fruits and vegetables and extra-virgin olive oil on attenuating sarcopenic symptomology in overweight and obese older adults during energy intake restriction: protocol paper

Background

Weight loss interventions have not been advocated for overweight/obese older adults due to potential loss of skeletal muscle and strength impacting on physical function with potential loss of independence. Carotenoids and polyphenols are inversely associated with sarcopenic symptomology. This paper reports the protocol of a study evaluating the efficacy of a high-protein, energy restricted diet rich in carotenoids and polyphenols on body composition, muscle strength, physical performance and quality of life in overweight and obese older adults.

Methods

This randomised controlled clinical trial will recruit community-dwelling, healthy overweight and obese older adults (≥60 years) for a 12-week weight loss intervention. Seventy-three participants will be recruited and randomized to an energy restricted (~30% restriction), isocaloric diet (30% protein; 30% carbohydrate; 40% fat) enriched with either: a) 375 g/d of high carotenoid vegetables, 300 g/d high carotenoid fruit, and 40-60 ml extra-virgin olive oil (EVOO); or b) 375 g/d of lower carotenoid vegetables, 300 g/d lower carotenoid fruit, and 40-60 ml Polyunsaturated fatty acid (PUFA) based oil. All participants will receive individual dietary counselling each fortnight for the duration of the study and will be asked to maintain their habitual level of physical activity throughout the study. The primary outcome will be appendicular skeletal muscle (ASM) assessed by dual energy X-ray absorptiometry (DXA). Secondary outcomes will include body weight, fat-free mass (FFM), fat mass (FM), muscle strength (Isometric hand-grip strength), physical performance (Short Physical Performance Battery), physical activity (International Physical Activity Questionnaire) and health related quality of life (SF-36). Outcomes will be measured at baseline and at week 12.

Discussion

The results of this study will provide a novel insight relating to the potential influence of high carotenoid and polyphenol intakes on attenuation of ASM during dietary energy-restricted weight loss in overweight and obese older adults.

Trial registration

The trial was registered on the Australia New Zealand Clinical Trials Register (ACTRN12616001400459); Trial registration date: 10th October, 2016.

Validity of Dietary Assessment in Athletes: A Systematic Review

Dietary assessment methods that are recognized as appropriate for the general population are usually applied in a similar manner to athletes, despite the knowledge that sport-specific factors can complicate assessment and impact accuracy in unique ways. As dietary assessment methods are used extensively within the field of sports nutrition, there is concern the validity of methodologies have not undergone more rigorous evaluation in this unique population sub-group. The purpose of this systematic review was to compare two or more methods of dietary assessment, including dietary intake measured against biomarkers or reference measures of energy expenditure, in athletes. Six electronic databases were searched for English-language, full-text articles published from January 1980 until June 2016. The search strategy combined the following keywords: diet, nutrition assessment, athlete, and validity; where the following outcomes are reported but not limited to: energy intake, macro and/or micronutrient intake, food intake, nutritional adequacy, diet quality, or nutritional status. Meta-analysis was performed on studies with sufficient methodological similarity, with between-group standardized mean differences (or effect size) and 95% confidence intervals (CI) being calculated. Of the 1624 studies identified, 18 were eligible for inclusion. Studies comparing self-reported energy intake (EI) to energy expenditure assessed via doubly labelled water were grouped for comparison (n = 11) and demonstrated mean EI was under-estimated by 19% (-2793 ± 1134 kJ/day). Meta-analysis revealed a large pooled effect size of -1.006 (95% CI: -1.3 to -0.7; p < 0.001). The remaining studies (n = 7) compared a new dietary tool or instrument to a reference method(s) (e.g., food record, 24-h dietary recall, biomarker) as part of a validation study. This systematic review revealed there are limited robust studies evaluating dietary assessment methods in athletes. Existing literature demonstrates the substantial variability between methods, with under- and misreporting of intake being frequently observed. There is a clear need for careful validation of dietary assessment methods, including emerging technical innovations, among athlete populations.

Prevalence of Exercise Addiction Symptomology and Disordered Eating in Australian Students Studying Nutrition and Dietetics

BACKGROUND

Previous research has reported the existence of disordered eating in students studying nutrition and dietetics. However, the occurrence of exercise addiction, previously linked to disordered eating, is poorly understood in this group.

OBJECTIVE

The main objective of this study was to explore the prevalence of self-reported symptoms of exercise addiction and the association with disordered eating in a sample of students studying nutrition and dietetics. A secondary objective was to compare the prevalence of exercise addiction to students enrolled in another health-related degree.

DESIGN

We conducted a cross-sectional study in 165 undergraduate students.

PARTICIPANTS/SETTING

Participants were students of both sexes enrolled in nutrition and dietetics and occupational therapy degree programs at an Australian university in August 2013.

MAIN OUTCOME MEASURES

Participants completed four validated questionnaires for assessment of exercise- and eating-related attitudes and behaviors measuring scores for exercise addiction, weekly volume of physical activity (PA), eating disorder symptoms, and cognitive restraint. Stretch stature and body mass were measured and body composition was assessed using dual energy x-ray absorptiometry.

STATISTICAL ANALYSES PERFORMED

Independent t test, Mann-Whitney U test, and χ² test were completed to compare groups of students based on sex, degree, or eating attitudes. Spearman's correlation was performed to explore associations between continuous variables (exercise addiction scores, PA volume, and scores for eating attitudes and cognitive restraint).

RESULTS

Approximately 23% of nutrition and dietetics students were found to be at risk of exercise addiction (20% females and 35% males; P=0.205), while the majority demonstrated some symptoms of exercise addiction. A similar proportion of at risk individuals was found in the female occupational therapy group (19%; P=1.000). In females (nutrition and dietetics and occupational therapy combined), the exercise addiction scores were associated with three other outcome measures: PA volume (r_s=0.41; P<0.001), eating attitudes scores (r_s=0.24; P=0.008), and cognitive restraint (r_s=0.32; P<0.001). Comparative analysis indicated that female students with high cognitive restraint had greater exercise addiction scores than those with low cognitive restraint (20.3 [4.8] compared to 17.8 [4.2]; P=0.003).

CONCLUSIONS

Results suggest high prevalence of exercise addiction in this sample of undergraduate health-related degree students and its link to amount of PA and disordered eating in females. Future research should include larger samples of both sexes to build the existing understanding on these maladaptive behaviors.

The relationship between dietary intake and energy availability, eating attitudes and cognitive restraint in students enrolled in undergraduate nutrition degrees

The aim of this research was to explore the relationship of total energy and macronutrient intake, energy balance and energy availability to eating attitudes and cognitive restraint in students enrolled in undergraduate nutrition degrees. Energy and micronutrient intake was assessed in 63 students (n = 50 nutrition, and n = 13 occupation therapy degrees; n = 51 females, n = 12 males) using three 24-h dietary recalls. Energy requirements were calculated based on measured resting metabolic rate, estimated exercise energy expenditure, and dietary induced thermogenesis. Body composition was assessed using dual energy x-ray absorptiometry. Eating attitudes and cognitive restraint were measured using previously validated tools. Eighteen percent of nutrition students were classified as having low energy availability (<30 kcal kgFFM^-1d^-1) and 38% were in negative energy balance. Eating attitudes and cognitive restraint were not associated with total energy or macronutrient intake. However, female nutrition students with high cognitive restraint had greater exercise energy expenditure and thus lower energy availability than those with low cognitive restraint (371 (302) kcal d^-1 compared to 145 (206) kcal d^-1, P < 0.01, and 35 (7) kcal d^-1 compared to 41 (10) kcal d^-1 of fat free mass, P = 0.005). Additionally, in females, disordered eating attitudes and cognitive restraint negatively correlated with energy availability (r_s = -0.37, P = 0.02 and r_s = -0.51, P < 0.01 respectively). There were no differences in outcomes between nutrition and non-nutrition students. The current study suggests that those students with disordered eating attitudes and cognitive restraint may be controlling their energy balance through exercise, as opposed to restricting food intake.

Eating attitudes and behaviours of students enrolled in undergraduate nutrition and dietetics degrees

AIM

The prevalence of disordered eating has been frequently reported in university students; however, the prevalence amongst Australian undergraduate students studying degrees with a focus on nutrition is uncertain. The aims of this study were to: (i) assess eating attitudes and behaviours of students enrolled in nutrition and dietetics, (ii) compare those to students enrolled in another health degree of occupational therapy (OT) and (iii) explore possible relationships between eating attitudes and behaviours and other characteristics of both cohorts.

METHODS

This cross-sectional observational study investigated self-reported anthropometric characteristics, eating attitudes and behaviours and self-esteem using a series of questionnaires.

RESULTS

Participants included 137 students (119 females, 18 males) with a mean age of 27.1 ± 8.7 years. Fourteen percent of nutrition and dietetics and 11% of OT students had disordered eating attitudes scores that were symptomatic of an eating disorder. Mean eating attitude scores did not differ between the degrees of study. Students in nutrition and dietetics showed significantly higher levels of cognitive restraint and less emotional eating than OT students. Enrolment in the first year of study was the strongest predictor of symptomatic eating attitudes.

CONCLUSIONS

These findings support previously expressed concern about presence of disordered eating in nutrition and dietetics undergraduates. Collaboratively developed support mechanisms for preventing and managing disordered relationships with food would be of benefit to students enrolled in nutrition degrees to ensure ongoing professional integrity.

Dietary Intake of Competitive Bodybuilders

BACKGROUND

Competitive bodybuilders are well known for extreme physique traits and extremes in diet and training manipulation to optimize lean mass and achieve a low body fat. Although many of the dietary dogmas in bodybuilding lack scientific scrutiny, a number, including timing and dosing of high biological value proteins across the day, have more recently been confirmed as effective by empirical research studies. A more comprehensive understanding of the dietary intakes of bodybuilders has the potential to uncover other dietary approaches, deserving of scientific investigation, with application to the wider sporting, and potential health contexts, where manipulation of physique traits is desired.

OBJECTIVE

Our objective was to conduct a systematic review of dietary intake practices of competitive bodybuilders, evaluate the quality and currency of the existing literature, and identify research gaps to inform future studies.

METHODS

A systematic search of electronic databases was conducted from the earliest record until March 2014. The search combined permutations of the terms 'bodybuilding', 'dietary intake', and 'dietary supplement'. Included studies needed to report quantitative data (energy and macronutrients at a minimum) on habitual dietary intake of competitive bodybuilders.

RESULTS

The 18 manuscripts meeting eligibility criteria reported on 385 participants (n = 62 women). Most studies were published in the 1980-1990s, with three published in the past 5 years. Study methodological quality was evaluated as poor. Energy intake ranged from 10 to 24 MJ/day for men and from 4 to 14 MJ/day for women. Protein intake ranged from 1.9 to 4.3 g/kg for men and from 0.8 to 2.8 g/kg for women. Intake of carbohydrate and fat was <6 g/kg/day and below 30% of energy, respectively. Carbohydrate intakes were below, and protein (in men) intakes were higher than, the current recommendations for strength athletes, with no consideration for exploration of macronutrient quality or distribution over the day. Energy intakes varied over different phases of preparation, typically being highest in the non-competition (>6 months from competition) or immediate post-competition period and lowest during competition preparation (≤6 months from competition) or competition week. The most commonly reported dietary supplements were protein powders/liquids and amino acids. The studies failed to provide details on rationale for different dietary intakes. The contribution of diet supplements was also often not reported. When supplements were reported, intakes of some micronutrients were excessive (~1000% of US Recommended Dietary Allowance) and above the tolerable upper limit.

CONCLUSION

This review demonstrates that literature describing the dietary intake practices of competitive bodybuilders is dated and often of poor quality. Intake reporting required better specificity and details of the rationale underpinning the use. The review suggests that high-quality contemporary research is needed in this area, with the potential to uncover dietary strategies worthy of scientific exploration.

Patterning microparticles on a template of aggregated cationic dye

Patternwise aggregation of charged molecules on a surface is potentially a facile approach to generate a template on which to pattern oppositely charged microparticles. We report on the patterning of silica microparticles by a system comprising a photopatternable copolymer and an aggregate forming penta-cationic cyanine dye. A thin film of the copolymer, composed of a molar excess of styrenesulfonic acid oxime ester to cross-linkable glycidyl methacrylate monomomers, was exposed through a mask and neutralized, resulting in a pattern of hydrophobic areas, and where exposed, a hydrophilic cross-linked film with sodium poly(styrenesulfonate) domains. The occurrence and locus of aggregation of an aqueous solution of the dye, applied to the patterned surface was established by absorbance and fluorescence spectroscopy and atomic force microscopy. In exposed areas, dye is imbibed and aggregation induced in sodium styrenesulfonate domains internal to the layer, whereas in the unexposed areas the dye aggregates on the hydrophobic surface. Aqueous anionic silica microparticles applied to the dye treated patterned surface and then rinsed, are retained in the unexposed areas having cationic surface aggregates, but rejected from the exposed areas with internal dye aggregates as these areas retain net negative charge. Mask exposure, absent dye treatment, did not result in patterning as negatively charged microparticles were nowhere retained, and positively charged particles were everywhere retained. The extent of surface coverage by the dye in unexposed areas was deposition time dependent, and ranged from isolated patches covering about 20 percent of the polymer surface to a surface saturated layer, with silica particle patterning robust over the range of dye surface coverages studied. The force requirements to pattern the denser than water silica microparticles are identified, and particle and polymer film surface potentials that meet the critical repulsion force requirement are mapped using an established sphere-to-flat surface electric double layer (EDL) model.

Reconstruction of limnology and microbialite formation conditions from carbonate clumped isotope thermometry

Quantitative tools for deciphering the environment of microbialite formation are relatively limited. For example, the oxygen isotope carbonate-water geothermometer requires assumptions about the isotopic composition of the water of formation. We explored the utility of using 'clumped' isotope thermometry as a tool to study the temperatures of microbialite formation. We studied microbialites recovered from water depths of 10-55 m in Pavilion Lake, and 10-25 m in Kelly Lake, spanning the thermocline in both lakes. We determined the temperature of carbonate growth and the (18)O/(16)O ratio of the waters that microbialites grew in. Results were then compared to current limnological data from the lakes to reconstruct the history of microbialite formation. Modern microbialites collected at shallow depths (11.7 m) in both lakes yield clumped isotope-based temperatures of formation that are within error of summer water temperatures, suggesting that clumped isotope analyses may be used to reconstruct past climates and to probe the environments in which microbialites formed. The deepest microbialites (21.7-55 m) were recovered from below the present-day thermoclines in both lakes and yield radioisotope ages indicating they primarily formed earlier in the Holocene. During this time, pollen data and our reconstructed water (18)O/(16)O ratios indicate a period of aridity, with lower lake levels. At present, there is a close association between both photosynthetic and heterotrophic communities, and carbonate precipitation/microbialite formation, with biosignatures of photosynthetic influences on carbonate detected in microbialites from the photic zone and above the thermocline (i.e., depths of generally <20 m). Given the deeper microbialites are receiving <1% of photosynthetically active radiation (PAR), it is likely these microbialites primarily formed when lower lake levels resulted in microbialites being located higher in the photic zone, in warm surface waters.

Getting a grip on the evolution of grasping in musteloid carnivorans: a three-dimensional analysis of forelimb shape

The ability to grasp and manipulate is often considered a hallmark of hominins and associated with the evolution of their bipedal locomotion and tool use. Yet, many other mammals use their forelimbs to grasp and manipulate objects. Previous investigations have suggested that grasping may be derived from digging behaviour, arboreal locomotion or hunting behaviour. Here, we test the arboreal origin of grasping and investigate whether an arboreal lifestyle could confer a greater grasping ability in musteloid carnivorans. Moreover, we investigate the morphological adaptations related to grasping and the differences between arboreal species with different grasping abilities. We predict that if grasping is derived from an arboreal lifestyle, then the anatomical specializations of the forelimb for arboreality must be similar to those involved in grasping. We further predict that arboreal species with a well-developed manipulation ability will have articulations that facilitate radio-ulnar rotation. We use ancestral character state reconstructions of lifestyle and grasping ability to understand the evolution of both traits. Finally, we use a surface sliding semi-landmark approach capable of quantifying the articulations in their full complexity. Our results largely confirm our predictions, demonstrating that musteloids with greater grasping skills differ markedly from others in the shape of their forelimb bones. These analyses further suggest that the evolution of an arboreal lifestyle likely preceded the development of enhanced grasping ability.

Nutrition guidelines for strength sports: sprinting, weightlifting, throwing events, and bodybuilding

Strength and power athletes are primarily interested in enhancing power relative to body weight and thus almost all undertake some form of resistance training. While athletes may periodically attempt to promote skeletal muscle hypertrophy, key nutritional issues are broader than those pertinent to hypertrophy and include an appreciation of the sports supplement industry, the strategic timing of nutrient intake to maximize fuelling and recovery objectives, plus achievement of pre-competition body mass requirements. Total energy and macronutrient intakes of strength-power athletes are generally high but intakes tend to be unremarkable when expressed relative to body mass. Greater insight into optimization of dietary intake to achieve nutrition-related goals would be achieved from assessment of nutrient distribution over the day, especially intake before, during, and after exercise. This information is not readily available on strength-power athletes and research is warranted. There is a general void of scientific investigation relating specifically to this unique group of athletes. Until this is resolved, sports nutrition recommendations for strength-power athletes should be directed at the individual athlete, focusing on their specific nutrition-related goals, with an emphasis on the nutritional support of training.

Constraining carbon sources and growth rates of freshwater microbialites in Pavilion Lake using (14)C analysis

This study determined the natural abundance isotopic compositions ((13)C, (14)C) of the primary carbon pools and microbial communities associated with modern freshwater microbialites located in Pavilion Lake, British Columbia, Canada. The Delta(14)C of dissolved inorganic carbon (DIC) was constant throughout the water column and consistent with a primarily atmospheric source. Observed depletions in DIC (14)C values compared with atmospheric CO(2) indicated effects due either to DIC residence time and/or inputs of (14)C-depleted groundwater. Mass balance comparisons of local and regional groundwater indicate that groundwater DIC could contribute a maximum of 9-13% of the DIC. (14)C analysis of microbial phospholipid fatty acids from microbialite communities had Delta(14)C values comparable with lake water DIC, demonstrating that lake water DIC was their primary carbon source. Microbialite carbonate was also primarily derived from DIC. However, some depletion in microbialite carbonate (14)C relative to lake water DIC occurred, due either to residence time or mixing with a (14)C-depleted carbon source. A detrital branch covered with microbialite growth was used to estimate a microbialite growth rate of 0.05 mm year(-1) for the past 1000 years, faster than previous estimates for this system. These results demonstrate that the microbialites are actively growing and that the primary carbon source for both microbial communities and recent carbonate is DIC originating from the atmosphere. While these data cannot conclusively differentiate between abiotic and biotic formation mechanisms, the evidence for minor inputs of groundwater-derived DIC is consistent with the previously hypothesized biological origin of the Pavilion Lake microbialites.

Organic solvent-dispersed TiO(2) nanoparticle characterization

Anatase titanium dioxide nanoparticles are derivatized with the polymerizable reagent (3-methacryloxypropyl)trimethoxysilane to provide dispersions in organic solvent. The titania core particles are characterized by transmission electron microscopy (TEM) and X-ray diffraction (XRD). The organic component structures and thickness are elucidated using nuclear magnetic resonance (NMR), quasielastic light scattering (QELS), and size-exclusion chromatography (SEC). Thin, high-refractive-index coatings prepared from the organic dispersions are characterized by atomic force microscopy (AFM). The combination of microscopies, spectroscopy, light scattering, and separation techniques provides unique information on the structure, thickness, morphology, and size distributions of the surface-treated nanoparticles that is difficult to obtain by any single technique. The findings indicate titania platelets with a modal diameter of 9.8 nm and a thickness of approximately 1.5 nm. The particles are coated with a 1.5-1.9 nm thick organic ligand layer, and a substantial population of 2 nm siloxane oligomers is detected. The analytical methodology presented may also be useful for characterizing other anisotropic organic-inorganic nanoparticles and their dispersions.

Ensembl 2009

The Ensembl project (http://www.ensembl.org) is a comprehensive genome information system featuring an integrated set of genome annotation, databases, and other information for chordate, selected model organism and disease vector genomes. As of release 51 (November 2008), Ensembl fully supports 45 species, and three additional species have preliminary support. New species in the past year include orangutan and six additional low coverage mammalian genomes. Major additions and improvements to Ensembl since our previous report include a major redesign of our website; generation of multiple genome alignments and ancestral sequences using the new Enredo-Pecan-Ortheus pipeline and development of our software infrastructure, particularly to support the Ensembl Genomes project (http://www.ensemblgenomes.org/).

Ensembl 2008

The Ensembl project (http://www.ensembl.org) is a comprehensive genome information system featuring an integrated set of genome annotation, databases and other information for chordate and selected model organism and disease vector genomes. As of release 47 (October 2007), Ensembl fully supports 35 species, with preliminary support for six additional species. New species in the past year include platypus and horse. Major additions and improvements to Ensembl since our previous report include extensive support for functional genomics data in the form of a specialized functional genomics database, genome-wide maps of protein–DNA interactions and the Ensembl regulatory build; support for customization of the Ensembl web interface through the addition of user accounts and user groups; and increased support for genome resequencing. We have also introduced new comparative genomics-based data mining options and report on the continued development of our software infrastructure.