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Comparisons between how bison and cattle grazing affect the plant community are understood poorly because of confounding differences in how the herbivores are typically managed. This 10-year study compared vegetation changes in Kansas (USA) tallgrass prairie that was burned and grazed season-long at a moderate stocking rate by either bison or cattle. We held management practices constant between the herbivores and equalized grazing pressure by matching animals so that the total body mass in all pastures was similar each year. Trends in species cover and diversity indices in the bison and cattle pastures were compared with ungrazed prairie that also was burned annually. We found that little bluestem (Schizachyrium scoparium) cover decreased over time in bison pastures, and big bluestem (Andropogon gerardii) cover increased over time in cattle pastures. Grazing by either herbivore increased the canopy cover of annual forbs, perennial forbs, and cool-season graminoids, but both annual and perennial forb cover increased at a greater rate in bison pastures than in cattle pastures. Missouri goldenrod (Solidago missouriensis) and heath aster (Symphyotrichum ericoides) were primarily responsible for the increased forb cover in grazed pastures. Species richness at both small (10 m2) and large (200 m2) spatial scales increased at a greater rate in bison pastures than in cattle pastures, but richness did not change through time in ungrazed prairie. The number of annual forb species was significantly higher in bison pastures than in pastures grazed by cattle. Residual graminoid biomass at the end of the grazing season was lower in bison pastures than in cattle pastures, whereas forb residuum increased over time at a greater rate in pastures grazed by bison than in pastures grazed by cattle. Although bison and cattle differentially altered some vegetation components, the plant communities in bison and cattle pastures were 85% similar after 10 years of grazing. We conclude that most measurable differences between bison-grazed and cattle-grazed pastures in tallgrass prairie are relatively minor, and differences in how the herbivores are typically managed may play a larger role in their impact on prairie vegetation than differences between the species.

Microtubule-based transport by the kinesin motors, powered by ATP hydrolysis, is essential for a wide range of vital processes in eukaryotes. We obtained insight into this process by developing atomic models for no-nucleotide and ATP states of the monomeric kinesin motor domain on microtubules from cryo-EM reconstructions at 5–6 Å resolution. By comparing these models with existing X-ray structures of ADP-bound kinesin, we infer a mechanistic scheme in which microtubule attachment, mediated by a universally conserved ‘linchpin’ residue in kinesin (N255), triggers a clamshell opening of the nucleotide cleft and accompanying release of ADP. Binding of ATP re-closes the cleft in a manner that tightly couples to translocation of cargo, via kinesin's ‘neck linker’ element. These structural transitions are reminiscent of the analogous nucleotide-exchange steps in the myosin and F1-ATPase motors and inform how the two heads of a kinesin dimer ‘gate’ each other to promote coordinated stepping along microtubules. The inside of a cell is a dynamic environment. Large molecules such as proteins are commonly transported within a cell by ‘motor proteins’, which move along a network of filaments called microtubules. One group of motor proteins, the kinesins, typically have one end called a motor domain that attaches itself to a microtubule. The other end links to the cargo being carried, and a flexible ‘neck’ region connects the two ends of the motor protein. Kinesins are bound together in pairs. The flexible neck region allows each motor domain in a pair to move past that of the other, allowing the kinesin to ‘walk’ along a microtubule in a step-like manner. Each step requires one motor domain to alternately tightly associate with, and then release from, a microtubule filament. This alternating cycle is coordinated by kinesin binding to and breaking down a molecule called ATP to form another molecule called ADP, which releases the energy needed for its next step. This repeating cycle is possible because a motor domain changes shape when it binds to a microtubule. This shape change stimulates the release of ADP, freeing up room for a new ATP molecule to bind to the motor domain. Although relatively small, these structural changes produce larger changes in the flexible neck region that enable the individual motor domains within a kinesin pair to co-ordinate their movement and move efficiently. Many previous studies have investigated these shape changes using a technique called cryo-electron microscopy, which rapidly freezes samples and allows their structure to be recorded in high detail. However, the small size of the motor domains and their changes in shape means that this technique was not able to reveal the structures in full detail. Shang et al. now exploit recent advances in cryo-electron microscopy to examine the structural changes of individual kinesin motor domains in greater detail. Images of motor domains bound to microtubules were made while the motor domain was in one of two different states: not bound to ATP or ADP, or bound to a chemically modified form of ATP that cannot be broken down. Shang et al. then used these images to produce models of the motor domains and compared the models with previously published images. This revealed a cleft in the kinesin motor domain that opens when it attaches to a microtubule. This cleft's ‘clamshell-like’ opening allows ADP to be released; it then closes when a molecule of ATP binds to it. The opening and closing of the cleft causes the changes in the ‘neck linker’ of the kinesin that enable the motor protein to transport its cargo, and so links ATP binding to the movement of the motor protein. Shang et al. suggest that similar processes may also occur in other motor proteins that have not been as well studied as the kinesins.

Clinical trial managers play a vital role in the design and conduct of clinical trials in the UK. There is a current recruitment and retention crisis for this specialist role due to a complex set of factors, most likely to have come to a head due to the COVID-19 pandemic. Academic clinical trial units and departments are struggling to recruit trial managers to vacant positions, and multiple influences are affecting the retention of this highly skilled workforce. Without tackling this issue, we face major challenges in the delivery on the Department of Health and Social Care’s Future of UK Clinical Research Delivery implementation plan. This article, led by a leading network of and for UK Trial Managers, presents some of the issues and ways in which national stakeholders may be able to address this.

Urinary incontinence is common immediately after prostate surgery. Men are often advised to do pelvic-floor exercises, but evidence to support this is inconclusive. Our aim was to establish if formal one-to-one pelvic floor muscle training reduces incontinence. We undertook two randomised trials in men in the UK who were incontinent 6 weeks after radical prostatectomy (trial 1) or transurethral resection of the prostate (TURP; trial 2) to compare four sessions with a therapist over 3 months with standard care and lifestyle advice only. Randomisation was by remote computer allocation. Our primary endpoints, collected via postal questionnaires, were participants' reports of urinary incontinence and incremental cost per quality-adjusted life year (QALY) after 12 months. Group assignment was masked from outcome assessors, but this masking was not possible for participants or caregivers. We used intention-to-treat analyses to compare the primary outcome at 12 months. This study is registered, number ISRCTN87696430. In the intervention group in trial 1, the rate of urinary incontinence at 12 months (148 [76%] of 196) was not significantly different from the control group (151 [77%] of 195; absolute risk difference [RD] −1·9%, 95% CI −10 to 6). In trial 2, the difference in the rate of urinary incontinence at 12 months (126 [65%] of 194) from the control group was not significant (125 [62%] of 203; RD 3·4%, 95% CI −6 to 13). Adjusting for minimisation factors or doing treatment-received analyses did not change these results in either trial. No adverse effects were reported. In both trials, the intervention resulted in higher mean costs per patient (£180 and £209 respectively) but we did not identify evidence of an economically important difference in QALYs (0·002 [95% CI −0·027 to 0·023] and −0·00003 [−0·026 to 0·026]). In settings where information about pelvic-floor exercise is widely available, one-to-one conservative physical therapy for men who are incontinent after prostate surgery is unlikely to be effective or cost effective. The high rates of persisting incontinence after 12 months suggest a substantial unrecognised and unmet need for management in these men. National Institute of Health Research, Health Technology Assessment (NIHR HTA) Programme.

We evaluated the effect of increasing amounts of rumen-degradable intake protein (DIP) on urea kinetics in steers consuming prairie hay. Ruminally and duodenally fistulated steers (278 kg of BW) were used in a 4 x 4 Latin square and provided ad libitum access to low-quality prairie hay (4.9% CP). The DIP was provided as casein dosed ruminally once daily in amounts of 0, 59, 118, and 177 mg of N/kg of BW daily. Periods were 13 d long, with 7 d for adaptation and 6 d for collection. Steers were in metabolism crates for total collection of urine and feces. Jugular infusion of ¹⁵N¹⁵N-urea, followed by determination of urinary enrichment of ¹⁵N¹⁵N-urea and ¹⁴N¹⁵N-urea was used to determine urea kinetics. Forage and N intake increased (linear, P < 0.001) with increasing DIP. Retention of N was negative (-2.7 g/d) for steers receiving no DIP and increased linearly (P < 0.001; 11.7, 23.0, and 35.2 g/d for 59, 118, and 177 mg of N/kg of BW daily) with DIP. Urea synthesis was 19.9, 24.8, 42.9, and 50.9 g of urea-N/d for 0, 59, 118, and 177 mg of N/kg of BW daily (linear, P = 0.004). Entry of urea into the gut was 98.9, 98.8, 98.6, and 95.9% of production for 0, 59, 118, and 177 mg of N/kg of BW daily, respectively (quadratic, P = 0.003). The amount of urea-N entering the gastrointestinal tract was greatest for 177 mg of N/kg of BW daily (48.6 g of urea-N/d) and decreased (linear, P = 0.005) to 42.4, 24.5, and 19.8 g of urea-N/d for 118, 59, and 0 mg of N/kg of BW daily. Microbial incorporation of recycled urea-N increased linearly (P = 0.02) from 12.3 g of N/d for 0 mg of N/kg of BW daily to 28.9 g of N/d for 177 mg of N/kg of BW daily. Provision of DIP produced the desired and previously observed increase in forage intake while also increasing N retention. The large percentage of urea synthesis that was recycled to the gut (95.9% even when steers received the greatest amount of DIP) points to the remarkable ability of cattle to conserve N when fed a low-protein diet.

Objectives This paper tests theoretical arguments that suggest court actors hold gendered views of sex offenders that result in a gender gap in sex offender punishment, where women who commit sexual offenses are treated more leniently than their male counterparts. Methods We test this argument with precision matching analyses using 15 years of data on all felony sex offenders sentenced in a single state. Results Results indicate that gender disparities in sex offender sentencing exist and are pervasive across sex offense types. Specifically, male sex offenders are more likely to be sentenced to prison, and given longer terms, than female sex offenders. Findings are similar across sex offense severity and whether the offense involved a minor victim. Conclusions These findings suggest that female sex offenders are treated more leniently than their matched male counterparts, even in instances of more serious sex offenses and those involving minor victims. Findings support theoretical arguments that contend that court decision-making is influenced by legally-irrelevant characteristics and raise questions about the source of gendered views of sex offenders and their effects on punishment approaches. Findings also raise questions about the virtue of get-tough sentencing policies that provide leeway for such dramatic variation across different groups of people.

When Hyperscale Data Centers first came on the market there was little concern about the outdoor air quality because the ventilation systems used within the server rooms utilized almost entirely recirculated air. While this approach may have successfully maintained adequate air quality within the server rooms, it came at a significant energy cost. In subsequent years, to reduce energy consumption, Hyperscale Data Centers have begun to use more outside makeup air in order to discharge the hot isle exhaust to the atmosphere.

Over the last two decades, in situ techniques have been used extensively for measuring ruminal degradation of feedstuffs. Current predictive models put renewed emphasis on the need for quantitative information regarding rates and extents of ruminal degradation. However, in situ techniques suffer from tremendous variation, both within and among laboratories. A considerable number of studies have evaluated the influence of various factors on in situ-derived estimates of ruminal degradation. Factors that should be addressed in a standardized procedure include bag and sample sizes; bag material and pore size; sample processing; animal diet, feeding level, and frequency; bag insertion and removal procedures; location of bags within the rumen and containment procedures for the bags; rinsing procedures; microbial correction; incubation times; mathematical models; and numbers of replicate animals, days, and bags required to obtain repeatable estimates of ruminal degradation. Several recommendations that should increase the precision of in situ measurements are presented. Currently, the lack of standardization in rinsing techniques and the failure or inability to correct for microbial contamination of in situ residues seem to be the major sources of variability with in situ procedures.

Although prior research links parental incarceration to deleterious outcomes for children during the life course, few studies have examined whether such incarceration affects the social exclusion of children during adolescence. Drawing on several lines of scholarship, the authors examined whether adolescents with incarcerated parents have fewer or lower quality relationships, participate in more antisocial peer networks, and feel less integrated or engaged in school. The study applies propensity score matching to survey and network data from a national sample of youth. Analyses indicated that children with incarcerated parents have more antisocial peers; the authors found limited evidence that parental incarceration adversely impacts peer networks and school integration domains. The results suggest that the impacts of parental incarceration on adolescents' social lives have less to do with isolation than with the types of peers adolescents befriend. Findings provide support for the idea that parental incarceration may adversely affect children's social exclusion.

The flexible tubulin C‐terminal tails (CTTs) have recently been implicated in the walking mechanism of dynein and kinesin. To address their role in the case of conventional kinesin, we examined the structure of kinesin–microtubule (MT) complexes before and after CTT cleavage by subtilisin. Our results show that the CTTs directly modulate the motor–tubulin interface and the binding properties of motors. CTT cleavage increases motor binding stability, and kinesin appears to adopt a binding conformation close to the nucleotide‐free configuration under most nucleotide conditions. Moreover, C‐terminal cleavage results in trapping a transient motor–ADP–MT intermediate. Using SH3‐tagged dimeric and monomeric constructs, we could also show that the position of the kinesin neck is not affected by the C‐terminal segments of tubulin. Overall, our study reveals that the tubulin C‐termini define the stability of the MT–kinesin complex in a nucleotide‐dependent manner, and highlights the involvement of tubulin in the regulation of weak and strong kinesin binding states.