The effect of number of knots per throw, knot technique, and suture type on strength properties of suspensory fixation button surgical procedures.

Background: Previous studies of the cortical suspensory button (CSB) implant have analyzed fixation strength as a function of suture type and surgical technique, but knot configuration remains an area of interest. This study investigates 4-strand knot configurations in CSB suspensory fixation, specifically comparing the use of 2 separate knots with a single knot. We hypothesize that using 2 knots on the distal side of the CSB with #2 suture will yield the strongest and stiffest suspensory fixation. Methods: Two types of knot configurations were compared: a single knot with all 4 suture strands versus 2 independent knots with 2 suture strands each (1 knot from inner strands and 1 knot from outer strands). They were tested using #2 or 2-0 suture, and at distal (on top of the button) or proximal (underneath the button) knot positions. Mechanical testing on the Instron measured ultimate failure load, elongation at failure, and stiffness. Statistical analyses (Shapiro-Wilk, unpaired Student's t-tests, and Chi-square tests) assessed differences in strength, stiffness, elongation, and failure mode between knot configurations within each CSB construct combination. Results: With #2 suture, 2 knots across the CSB resulted in higher load to failure compared to 1 knot in both proximal (467.00 N vs. 554.66 N, P = .026) and distal (395.18 N vs. 526.51 N, P < .001) locations. Furthermore, 2 knots provided higher stiffness than 1 knot in both proximal (53.24 N/mm vs. 67.89 N/mm, P < .001) and distal (47.08 N/mm vs. 56.73 N/mm, P = .041) knot locations. However, using 2-0 suture showed no significant differences in failure load and stiffness regardless of knot location. Conclusion: Using #2 suture and tying 2 independent knots across the CSB increased load to failure and stiffness compared to using only 1 knot regardless of knot position. Thus, if using #2 suture, it is recommended to tie 2 knots to enhance construct strength. However, with 2-0 suture, the number of knots did not impact construct strength. Therefore, if using 2-0 suture, 1 knot can be used to save time. Knot position did not significantly affect the strength or stiffness of the CSB construct, emphasizing the importance of considering knot prominence and surgical approach for determining knot location.

Ankle ligament reconstruction-return to sport after injury scale and return to sports after ankle ligament reconstruction or repair-A systematic review.

Purpose: To systematically review existing literature regarding the ankle ligament reconstruction-return to sport after injury (ALR-RSI) scale and to assess its correlation with Return to sport and functional outcomes as well as feasibility, reliability and consistency. Methods: A systematic review of the literature based on the Preferred Reporting Items for Systematic Reviews and Meta Analyses (PRISMA) was conducted using PubMed, Embase and Cochrane Library. Studies that evaluated psychological readiness to return to sport after ankle ligament reconstruction or repair for the treatment of chronic lateral ankle instability using the ALR-RSI scale were included. The results from each study were pooled, and weighted means and overall rates were calculated. Results: In total, 157 patients (53.2% male, mean age: 34.2 years) from three articles were included. Overall, 85.0% of patients reported successful return to sport, but only 48.9% of patients returned to the preoperative sporting level. All studies reported a significant difference in psychological scores between patients who returned to sport and those who did not. Pooled mean patient-reported outcome measures, reported as the American Orthopaedic Foot and Ankle Society Ankle-Hindfoot (AOFAS, three studies) Score and Karlsson-Peterson Score (three studies), were 82.7 (range: 29-100) and 81.7 (range: 25-100), respectively. The ALR-RSI scale demonstrated strong correlations with the AOFAS Score and Karlsson-Peterson Score. Conclusion: Patients who returned to sport after ankle ligament reconstruction or repair exhibited higher psychological readiness compared to those who did not. The ALR-RSI scale showed strong correlations with ankle function. Evaluation of psychological readiness using the ALR-RSI scale may provide an additional tool in the assessment of patients who underwent ankle ligament reconstruction or repair. Level of Evidence: Level III, systematic review.

Disentangling the effects of sulfate and other seawater ions on microbial communities and greenhouse gas emissions in a coastal forested wetland.

Seawater intrusion into freshwater wetlands causes changes in microbial communities and biogeochemistry, but the exact mechanisms driving these changes remain unclear. Here we use a manipulative laboratory microcosm experiment, combined with DNA sequencing and biogeochemical measurements, to tease apart the effects of sulfate from other seawater ions. We examined changes in microbial taxonomy and function as well as emissions of carbon dioxide, methane, and nitrous oxide in response to changes in ion concentrations. Greenhouse gas emissions and microbial richness and composition were altered by artificial seawater regardless of whether sulfate was present, whereas sulfate alone did not alter emissions or communities. Surprisingly, addition of sulfate alone did not lead to increases in the abundance of sulfate reducing bacteria or sulfur cycling genes. Similarly, genes involved in carbon, nitrogen, and phosphorus cycling responded more strongly to artificial seawater than to sulfate. These results suggest that other ions present in seawater, not sulfate, drive ecological and biogeochemical responses to seawater intrusion and may be drivers of increased methane emissions in soils that received artificial seawater addition. A better understanding of how the different components of salt water alter microbial community composition and function is necessary to forecast the consequences of coastal wetland salinization.

Multiple microbial guilds mediate soil methane cycling along a wetland salinity gradient.

Estuarine wetlands harbor considerable carbon stocks, but rising sea levels could affect their ability to sequester soil carbon as well as their potential to emit methane (CH4). While sulfate loading from seawater intrusion may reduce CH4 production due to the higher energy yield of microbial sulfate reduction, existing studies suggest other factors are likely at play. Our study of 11 wetland complexes spanning a natural salinity and productivity gradient across the San Francisco Bay and Delta found that while CH4 fluxes generally declined with salinity, they were highest in oligohaline wetlands (ca. 3-ppt salinity). Methanogens and methanogenesis genes were weakly correlated with CH4 fluxes but alone did not explain the highest rates observed. Taxonomic and functional gene data suggested that other microbial guilds that influence carbon and nitrogen cycling need to be accounted for to better predict CH4 fluxes at landscape scales. Higher methane production occurring near the freshwater boundary with slight salinization (and sulfate incursion) might result from increased sulfate-reducing fermenter and syntrophic populations, which can produce substrates used by methanogens. Moreover, higher salinities can solubilize ionically bound ammonium abundant in the lower salinity wetland soils examined here, which could inhibit methanotrophs and potentially contribute to greater CH4 fluxes observed in oligohaline sediments.IMPORTANCELow-level salinity intrusion could increase CH4 flux in tidal freshwater wetlands, while higher levels of salinization might instead decrease CH4 fluxes. High CH4 emissions in oligohaline sites are concerning because seawater intrusion will cause tidal freshwater wetlands to become oligohaline. Methanogenesis genes alone did not account for landscape patterns of CH4 fluxes, suggesting mechanisms altering methanogenesis, methanotrophy, nitrogen cycling, and ammonium release, and increasing decomposition and syntrophic bacterial populations could contribute to increases in net CH4 flux at oligohaline salinities. Improved understanding of these influences on net CH4 emissions could improve restoration efforts and accounting of carbon sequestration in estuarine wetlands. More pristine reference sites may have older and more abundant organic matter with higher carbon:nitrogen compared to wetlands impacted by agricultural activity and may present different interactions between salinity and CH4. This distinction might be critical for modeling efforts to scale up biogeochemical process interactions in estuarine wetlands.

Using high-density perimetry to explore new approaches for characterizing visual field defects.

High-density threshold perimetry has found that conventional static threshold perimetry misses defects due to undersampling. However, high-density testing can be both slow and limited by normal fixational eye movements. We explored alternatives by studying displays of high-density perimetry results for angioscotomas in healthy eyes-areas of reduced sensitivity in the shadows of blood vessels. The right eyes of four healthy adults were tested with a Digital Light Ophthalmoscope that gathered retinal images while presenting visual stimuli. The images were used to infer stimulus location on each trial. Contrast thresholds for a Goldmann size III stimulus were measured at 247 locations of a 13°×19° rectangular grid, with separation 0.5°, extending from 11° to 17° horizontally and -3° to +6° vertically, covering a portion of the optic nerve head and several major blood vessels. Maps of perimetric sensitivity identified diffuse regions of reduced sensitivity near the blood vessels, but these showed moderate structure-function agreement that was only modestly improved when effects of eye position were accounted for. An innovative method termed slice display was used to locate regions of reduced sensitivity. Slice display demonstrated that many fewer trials could yield similar structure-function agreement. These results are an indication that test duration might be reduced dramatically by focusing on location of defects rather than maps of sensitivity. Such alternatives to conventional threshold perimetry have the potential to map the shape of defects without the extensive time demands of high-density threshold perimetry. Simulations illustrate how such an algorithm could operate.

Current issues and future directions in gymnastics research: biomechanics, motor control and coaching interface.

The sport of gymnastics is undergoing a global examination of its culture and the relationship between the gymnast, coach and environment is a central focus. The aim of this review is to explore biomechanics and motor control research in skill development and technique selection in artistic gymnastics with a focus on the underlying concepts and scientific principles that allow performance enhancement, skill development and injury risk reduction. The current review examines peer reviewed papers from 2000 onwards, with a focus on contemporary approaches in the field of gymnastics research, and highlights several key directions for future gymnastics research. Based on our review and the integration of the models of Newell (1986) and Irwin et al. (2005), we recommend that future gymnastics research should embrace at the very least a multidisciplinary approach and aim for an interdisciplinary paradigm.

Microbial drivers of methane emissions from unrestored industrial salt ponds.

Wetlands are important carbon (C) sinks, yet many have been destroyed and converted to other uses over the past few centuries, including industrial salt making. A renewed focus on wetland ecosystem services (e.g., flood control, and habitat) has resulted in numerous restoration efforts whose effect on microbial communities is largely unexplored. We investigated the impact of restoration on microbial community composition, metabolic functional potential, and methane flux by analyzing sediment cores from two unrestored former industrial salt ponds, a restored former industrial salt pond, and a reference wetland. We observed elevated methane emissions from unrestored salt ponds compared to the restored and reference wetlands, which was positively correlated with salinity and sulfate across all samples. 16S rRNA gene amplicon and shotgun metagenomic data revealed that the restored salt pond harbored communities more phylogenetically and functionally similar to the reference wetland than to unrestored ponds. Archaeal methanogenesis genes were positively correlated with methane flux, as were genes encoding enzymes for bacterial methylphosphonate degradation, suggesting methane is generated both from bacterial methylphosphonate degradation and archaeal methanogenesis in these sites. These observations demonstrate that restoration effectively converted industrial salt pond microbial communities back to compositions more similar to reference wetlands and lowered salinities, sulfate concentrations, and methane emissions.

Optimizing single-chamber pacing in dogs. Part 2: Rate adaptive pacing.

Proper programming of pacemakers for dogs in the rate adaptive mode requires an understanding of the rate requirements for each individual and the interplay of programmable features. The specific advantages and disadvantages of the rate adaptive mode should be considered on a case by case basis. Fundamentally, two components are linked in the implementation of rate adaptive pacing: (1) sensing the need for a change in rate and (2) responding with the appropriate alteration in pacing rate. The programming interaction of these two components are interdependent and affected by the rates programmed. These features may be adjusted manually or automatically. In this review (Part 2 of a two-part review) the considerations required to program each aspect that optimizes the pacing rate profile are reviewed. These include the lower rate, upper sensor rate, activities of daily life rate, sensor threshold, acceleration and deceleration, slope, activities of daily life zone, exertion zone, automatic versus manual adjustments and closed loop stimulation. The programming features of pacemakers manufactured by three companies are summarized (Abbott, formerly St. Jude; Biotronik/Dextronix; Medtronic). Means of assessing the success of pacemaker programing is examined through examples of pacemaker data, Holter analysis, Poincaré plots and tachograms. Finally, the questions and considerations for rate adaptive pacing in dogs that demand investigation are proposed.

Optimizing single-chamber pacing in dogs Part 1: Rate determinations, rate interventions and hysteresis.

Determining ideal pacing rates to meet physiological needs and optimizing programming to prevent unnecessary right ventricular pacing in dogs requires an understanding of heart rate profiles and applicable pacing technology. The heart rate and rhythm of the dog is complex necessitating investigation of rate requirements of activity and circadian influences. Overlaying this information are a multiplicity of other factors such as age, breed, temperament, cardiovascular disease and underlining rhythm disorders that contribute to the difficulty in making general conclusions. However, all such information permits better implementation of programming options with the goal of better outcomes. In this review (Part 1 of a two-part review) instantaneous heart rate, rolling average heart rate, simple average heart rate, heart rate tachograms, RR interval tachograms (2D, 3D and dynamic), and Poincaré plots (2D, 3D and dynamic) are discussed as they apply to decisions in the determination and examination of pacing rates for dogs programmed in the VVI pacing mode (Ventricular paced, Ventricular sensed, Inhibited pacing). The applicable pacing operations available for three pacemaker companies are reviewed (Abbott, Biotronik/Dextronix, and Medtronic). The programmable options considered include: slowest pacing rate without additional features to extend the pacing interval, sleep/rest rate preferences, hysteresis to lengthen pacing interval following intrinsic beats, and intermittent increases in pacing following abrupt loss of intrinsic rhythm. Recommendations are suggested for follow-up of individual dogs with examination of pacing statistics and Holter monitoring.

Early initiation of direct anticoagulation after stroke in patients with atrial fibrillation.

BACKGROUND AND PURPOSE: The safety of early initiation of anticoagulant therapy in patients with ischaemic stroke related to atrial fibrillation (AF) is unknown. We investigated the safety of early initiation of direct oral anticoagulants (DOACs), vitamin K antagonists (VKAs) or no anticoagulation. METHODS: This observational, retrospective, single-centre study included consecutive patients with recent (<4 weeks) ischaemic stroke and AF. The primary outcome was the rate of major (intracranial and extracranial) bleeding in patients on different treatment schemes, i.e. DOACs, VKAs and not anticoagulated. We also investigated the rate of ischaemic cerebrovascular events and mortality. RESULTS: We included 959 consecutive patients with AF and ischaemic stroke followed up for an average of 16.1 days after the index event. A total of 559 out of 959 patients (58.3%) were anticoagulated with either VKAs (n = 259) or DOACs (n = 300). Anticoagulation was started after a mean of 7 ± 9.4 days in the DOAC group and 11.9 ± 19.7 days in the VKA group. Early initiation of any anticoagulant was not associated with an increased risk of any major bleeding [odds ratio (OR), 0.49; 95% confidence intervals (CI), 0.21-1.16] and in particular of intracranial bleeding (OR, 0.47; 95% CI, 0.17-1.29; P = 0.143) compared with no anticoagulation. In contrast to VKAs (OR, 0.78; 95% CI, 0.28-2.13), treatment with DOACs (OR, 0.32; 95% CI, 0.10-0.96) reduced the rate of major bleeding compared with no anticoagulation. Early recurrences of ischaemic stroke did not differ significantly among the three groups. CONCLUSIONS: Starting DOACs within a mean of 7 days after stroke appeared to be safe. Randomized controlled studies are needed to establish the added efficacy of starting anticoagulation early after stroke.

Insight into the Bacterial Endophytic Communities of Peach Cultivars Related to Crown Gall Disease Resistance.

Crown gall disease caused by Agrobacterium tumefaciens severely impacts the production of peach and other fruit trees. Several peach cultivars are partially resistant to A. tumefaciens, but little is known about the roles of endophytic microbiota in disease resistance. In the present study, the endophytic bacterial communities of resistant and susceptible peach cultivars "Honggengansutao" and "Okinawa" were analyzed using universal 16S rRNA gene amplicon sequencing in parallel with the cultivation and characterization of bacterial isolates. A total of 1,357,088 high-quality sequences representing 3,160 distinct operational taxonomic units (OTUs; Proteobacteria, Actinobacteria, Bacteroidetes, and Firmicutes) and 1,200 isolates of 20 genera and 305 distinct ribotypes were collected from peach roots and twigs. It was found that factors including plant developmental stage, cultivar, and A. tumefaciens invasion strongly influenced the peach endophytic communities. The community diversity of endophytic bacteria and the abundance of culturable bacteria were both higher in the roots of the resistant cultivar, particularly after inoculation. Strikingly, the pathogen antagonists Streptomyces and Pseudomonas in roots and Rhizobium in twigs were most frequently detected in resistant plants. Our results suggest that the higher abundance and diversity of endophytic bacteria and increased proportions of antagonistic bacteria might contribute to the natural defense of the resistant cultivar against A. tumefaciens This work reveals the relationships between endophytic bacteria and disease resistance in peach plants and provides important information for microbiome-based biocontrol of crown gall disease in fruit trees.IMPORTANCEAgrobacterium tumefaciens as the causal agent of peach crown gall disease can be controlled by planting resistant cultivars. This study profiles the endophytic bacteria in susceptible and resistant peach cultivars, advancing our understanding of the relationships between endophytic bacterial communities and peach crown gall disease, with potential implications for other complex microbiome-plant-pathogen interactions. The resistant cultivar may defend itself by increasing the diversity and abundance of beneficial endophytic bacteria. The antagonists identified among the genera Streptomyces, Pseudomonas, and Rhizobium may have application potential for biocontrol of crown gall disease in fruit trees.

Kinematic Comparison of Aquatic- and Land-Based Stationary Exercises in Overweight and Normal Weight Children.

PURPOSE: This study examined lower extremity kinematics in healthy weight (HW) and overweight (OW) children during water- and land-based stationary exercises (stationary running, frontal kick, and butt kick) at light submaximal intensity. METHODS: Participants included OW (N = 10; body fat percentage: 34.97 [8.60]) and HW (N = 15; body fat percentage: 18.33 [4.87]) children, aged 10 to 13 years. Spatiotemporal data, lower extremity joint kinematics, and rating of perceived exertion (RPE) were collected during water- and land-based stationary exercises. Repeated measures analysis of variance compared kinematic variables and RPE between groups and environments. A polygon area function compared coordination patterns between environments. RESULTS: RPE responses were significantly greater in OW than HW children on land (13.6 [0.7] vs 11.6 [0.7]; P < .001), whereas the RPE responses were similar between groups in water (11.2 [0.7] vs 11.1 [0.8]; P > .05). OW children were significantly more upright than HW children during land-based exercise, whereas there were no differences observed between groups during aquatic-based exercise. The duration of stance and swing phases, angular velocity, and cadence were significantly lower in water than on land. CONCLUSION: Compared with HW children, OW children performed stationary exercises in a more upright posture on land, with higher RPE. However, these differences diminished in water. Aquatic-based exercise may be effective in minimizing the effects of excess mass on OW children's ability to complete physical activity.

Lower extremity muscle function of front row rugby union scrummaging.

A rugby scrum's front row must act uniformly to transfer maximal horizontal force and improve performance. This study investigated the muscle activation patterns of lower extremity muscles in front row forwards during live and machine scrums at professional and amateur levels. Electromyography was collected bilaterally on vastus lateralis, rectus femoris and gastrocnemius muscles of 75 male rugby prop players during live and machine scrums. ANOVAs compared muscle reaction time, rate of change in muscle amplitude and muscle amplitude between groups and conditions. Cross-correlation analysis explored muscle synchronicity. There were significantly greater rates of change in each muscle amplitude in professional players than amateur players. Additionally, there was significantly quicker muscle reaction time in all muscles, and greater amplitude in vastus lateralis and gastrocnemius, during the live scrum vs. machine condition. The professional props produced more synchronised muscle activation than amateur players and all players produced more synchronised muscle activation against the scrum machine vs. live scrummage. The results indicate a higher skill proficiency and muscle synchronicity in professional players. While scrum machine training is ideally suited for functional muscle strengthening during practice, to truly simulate the requirements of the scrum, training should incorporate the live situation as much as possible.

Stationary Exercise in Overweight and Normal Weight Children.

PURPOSE: This study examined differences in lower extremity kinematics and muscle activation patterns between normal weight (NW) and overweight (OW) children during stationary exercises (running in place, frontal kick, and butt kick) at submaximal intensity. METHODS: Healthy children (aged 10-13 y) were stratified into OW (n = 10; body fat percentage: 34.97 [8.60]) and NW (n = 15; body fat percentage: 18.33 [4.87]). Electromyography was recorded for rectus femoris, vastus lateralis, biceps femoris, gastrocnemius, and tibialis anterior. In addition, the ratings of perceived exertion and range of motion of hip, knee, and ankle joints were collected during stationary exercises. Repeated-measures analysis of variance compared muscle activation, range of motion, and ratings of perceived exertion between groups and exercises. Friedman test examined sequencing of muscles recruitment. RESULTS: Compared with NW, OW experienced significantly greater ratings of perceived exertion (13.7 [0.8] vs 11.7 [0.7]; P < .001) and electromyography amplitude in all muscles apart from vastus lateralis during stationary exercises. In addition, NW children used more consistent muscles' recruitment pattern in comparison with OW children. The range of motion was similar between groups at all joints. CONCLUSION: OW children may adopt a more active neuromuscular strategy to provide greater stability and propulsion during stationary exercises. Stationary exercise can be prescribed to strengthen lower extremity muscles in OW children, but mode and intensity must be considered.

Beat-to-Beat Patterning of Sinus Rhythm Reveals Non-linear Rhythm in the Dog Compared to the Human.

The human and dog have sinus arrhythmia; however, the beat-to-beat interval changes were hypothesized to be different. Geometric analyses (R-R interval tachograms, dynamic Poincaré plots) to examine rate changes on a beat-to-beat basis were analyzed along with time and frequency domain heart rate variability from 40 human and 130 canine 24-h electrocardiographic recordings. Humans had bell-shaped beat-interval distributions, narrow interval bands across time with continuous interval change and linear changes in rate. In contrast, dogs had skewed non-singular beat distributions, wide interval bands {despite faster average heart rate of dogs [mean (range); 81 (64-119)] bpm compared to humans [74.5 (59-103) p = 0.005]} with regions displaying a paucity of intervals (zone of avoidance) and linear plus non-linear rate changes. In the dog, dynamic Poincaré plots showed linear rate changes as intervals prolonged until a point of divergence from the line of identity at a mean interval of 598.5 (95% CI: 583.5-613.5) ms (bifurcation interval). The dog had bimodal beat distribution during sleep with slower rates and greater variability than during active hours that showed singular interval distributions, higher rates and less variability. During sleep, Poincaré plots of the dog had clustered or branched patterns of intervals. A slower rate supported greater parasympathetic modulation with a branched compared to the clustered distribution. Treatment with atropine eliminated the non-linear patterns, while hydromorphone shifted the bifurcated branching and beat clustering to longer intervals. These results demonstrate the unique non-linear nature of beat-to-beat variability in the dog compared to humans with increases in interval duration (decrease heart rate). These results provoke the possibility that changes are linear with a dominant sympathetic modulation and non-linear with a dominant parasympathetic modulation. The abrupt bifurcation, zone of avoidance and beat-to-beat patterning are concordant with other studies demonstrating the development of exit block from the sinus node with parasympathetic modulation influencing not only the oscillation of the pacing cells, but conduction to the atria. Studies are required to associate the in vivo sinus node beat patterns identified in this study to the mapping of sinus impulse origin and exit from the sinus node.

Effects of consuming a high-protein diet with or without soy protein during weight loss and maintenance: a non-inferiority, randomized clinical efficacy trial.

OBJECTIVE: This 12-month randomized, non-inferiority clinical trial sought to determine the impact of consuming soy protein as part of an energy-restricted, high-protein diet on weight loss, body composition and cardiometabolic health. METHODS: Seventy-one adults (58 female) with overweight or obesity (body mass index: 32.9 ± 3.6 kg m-2) were randomly assigned to consume three servings of soy (S) or non-soy (NS) protein foods per day for 12 months. All participants completed a group-based behavioural weight loss program lasting 4 months (M4), and follow-up assessments were completed at month 12 (M12). RESULTS: Body weight was reduced in both groups at M4 (S: -7.0% ± 5.2%, NS: -7.1% ± 5.7%) and M12 (S: 3.6% ± 5.1%, NS: -4.8% ± 7.3%). Body weight reductions (mean difference [90% confidence interval]) were not different between S and NS at either time point (M4: -0.16% [-1.4, 3.6], P = 0.90; M12: 1.1% [-1.4, 3.6], P = 0.44). Differences in body fat mass loss were not different between S and NS at M4 (0.29 ± 0.84 kg, P = 0.73) or M12 (0.78 ± 1.5 kg, P = 0.59). Weight loss-induced improvements in cholesterol, triglycerides and blood pressure did not differ between S and NS. CONCLUSION: These results indicate that soy-based protein foods can be effectively incorporated into an energy-restricted, high-protein diet for improving body weight, body composition and cardiometabolic health.

Equivalent reductions in body weight during the Beef WISE Study: beef's role in weight improvement, satisfaction and energy.

OBJECTIVE: The objective of this randomized equivalence trial was to determine the impact of consuming lean beef as part of a high protein (HP) weight-reducing diet on changes in body weight, body composition and cardiometabolic health. METHODS: A total of 120 adults (99 female) with overweight or obesity (BMI: 35.7 ± 7.0 kg m-2) were randomly assigned to consume either a HP diet with ≥4 weekly servings of lean beef (B; n = 60) or a HP diet restricted in all red meats (NB; n = 60) during a 16-week weight loss intervention. RESULTS: Body weight was reduced by 7.8 ± 5.9% in B and 7.7 ± 5.5% in NB (p < 0.01 for both). Changes in percent body weight were equivalent between B and NB (mean difference: 0.06%, 90% confidence interval: (-1.7, 1.8)). Fat mass was reduced in both groups (p < 0.01; B: 8.0 ± 0.6 kg, NB: 8.6 ± 0.6 kg), while lean mass was not reduced in either group. Improvements in markers of cardiometabolic health (total cholesterol, low-density lipoprotein cholesterol, triglycerides and blood pressure) were not different between B and NB. CONCLUSION: Results of this study demonstrate that HP diets - either rich or restricted in red meat intakes - are effective for decreasing body weight and improving body composition and cardiometabolic health.

A genomic perspective on stoichiometric regulation of soil carbon cycling.

Similar to plant growth, soil carbon (C) cycling is constrained by the availability of nitrogen (N) and phosphorus (P). We hypothesized that stoichiometric control over soil microbial C cycling may be shaped by functional guilds with distinct nutrient substrate preferences. Across a series of rice fields spanning 5-25% soil C (N:P from 1:12 to 1:70), C turnover was best correlated with P availability and increased with experimental N addition only in lower C (mineral) soils with N:P⩽16. Microbial community membership also varied with soil stoichiometry but not with N addition. Shotgun metagenome data revealed changes in community functions with increasing C turnover, including a shift from aromatic C to carbohydrate utilization accompanied by lower N uptake and P scavenging. Similar patterns of C, N and P acquisition, along with higher ribosomal RNA operon copy numbers, distinguished that microbial taxa positively correlated with C turnover. Considering such tradeoffs in genomic resource allocation patterns among taxa strengthened correlations between microbial community composition and C cycling, suggesting simplified guilds amenable to ecosystem modeling. Our results suggest that patterns of soil C turnover may reflect community-dependent metabolic shifts driven by resource allocation strategies, analogous to growth rate-stoichiometry coupling in animal and plant communities.

Initial weight loss goals: have they changed and do they matter?

OBJECTIVE: Nearly 20 years ago, participants in behavioural weight loss programmes reported goals that greatly exceeded the amount of weight typically produced by these programmes. Whether having unrealistic weight loss goals impacts weight loss or attrition is unclear. The intent of the current study was to revisit current weight loss goals and examine whether goals impact outcomes. METHODS: Adults (N = 308, BMI = 33.7 ± 4.2 kg/m2) participated in a 12-month behavioural weight management programme and completed questionnaires about their goals. RESULTS: Participants' weight loss goal was 19.8 ± 7.9% of their body weight, and 90.4% selected a goal ≥10%. Weight goals were not associated with weight loss at 3 (p = 0.75) or 12 months (p = 0.47), or from 3 to 12 months (p = 0.55). Weight loss goals were not related to attrition at 3 (p = 0.91) or 12 months (p = 0.86). Participants believed that weight reduction would positively impact their health and psychosocial functioning. CONCLUSION: Weight loss goals have decreased, but still greatly exceed what can be expected by most. Unrealistic goals, however, had no impact on weight loss or attrition. These results question the utility of counseling people with obesity to set more realistic weight loss goals, which is typically practiced in behavioural weight management.