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The circadian clock is considered a key target for crop improvement because it controls metabolism and growth in Arabidopsis. Here, we show that the clock gene EARLY FLOWERING 3 (ELF3) controls vegetative growth in Arabidopsis but not in the cereal crop barley. Growth in Arabidopsis is determined by the degradation of leaf starch reserves at night, which is controlled by ELF3. The vegetative growth of barley, however, is determined by the depletion of leaf sucrose stores through an exponential kinetics, presumably catalyzed by the vacuolar sucrose exporter SUCROSE TRANSPORTER 2 (SUT2). This process depends on the sucrose content and the nighttime temperature but not on ELF3. The regulation of starch degradation and sucrose depletion in barley ensures efficient growth at favorable temperature as stores become exhausted at dawn. On cool nights, however, only the starch degradation rate is compensated against low nighttime temperatures, whereas the sucrose depletion rate is reduced. This coincides with reduced biomass in barley but not in Arabidopsis after growth in consecutive cool nights. The sucrose depletion metabolism determines growth in the cereal crops barley, wheat, and rice but is not generally conserved in monocot species and is not a domestication-related trait. Therefore, the control of growth by endogenous (clock) versus external factors (temperature) is species-specific and depends on the predominant carbohydrate store. Our results give new insights into the physiology of growth in cereals and provide a basis for studying the genetics and evolution of different carbohydrate stores and their contribution to plant productivity and adaptation.Significance StatementThe circadian clock controls growth in the model plant Arabidopsis thaliana by regulating the starch degradation rate so that reserves last until dawn. This prevents nocturnal starvation until photosynthesis resumes. The cereal crops barley, wheat and rice, however, predominantly consume sucrose instead of starch as carbohydrate source. We find that carbohydrate supply from sucrose at night is regulated by enzyme kinetics and night-time temperature, but not the circadian clock. We postulate that the regulation of growth depends on the predominant carbohydrate store, where starch degradation is controlled by endogenous cues (clock) and sucrose depletion by external factors (temperature). These differences in the regulation of carbohydrate availability at night may have important implications for adapting crops yields to climate change.

SummaryBarley (Hordeum vulgareL.) is an established model to study domestication of the Fertile Crescent cereals. Recent molecular data suggested that domesticated barley genomes consist of the ancestral blocks descending from multiple wild barley populations. However, the relationship between the mosaic ancestry patterns and the process of domestication itself remained unclear.To address this knowledge gap, we identified candidate domestication genes using selection scans based on targeted resequencing of 433 wild and domesticated barley accessions. We conducted phylogenetic, population structure, and ancestry analyses to investigate the origin of the domesticated barley haplotypes separately at the neutral and candidate domestication loci.We discovered multiple selective sweeps that occurred on all barley chromosomes during domestication in the background of several ancestral wild populations. The ancestry analyses demonstrated that, although the ancestral blocks of the domesticated barley genomes descended from all over the Fertile Crescent, the candidate domestication loci originated specifically in its eastern and western parts.These findings provided first molecular evidence in favor of multiple barley domestications in the Levantine and Zagros clusters of the origin of agriculture.

The routine care of people with chronic illnesses often fails to follow evidence-based guidelines or to achieve optimal outcomes.1,2 Because of the high prevalence and costs of chronic illness care3,4 and the key role of primary care physicians in managing chronic illness, enhancing care and outcomes in primary care settings is a public health imperative. There are important general issues about how chronic conditions are effectively managed.1,5,6 Identifying these generalities is essential if the potential advantages of primary care of chronic illness are to be realized. Evidence-based guidelines for diverse chronic conditions identify similar elements of patient care (first table,second table).7,8,9,10,11,12 These elements include a well-defined care plan, patient education, scheduled follow ups, outcome and adherence monitoring, the targeted use of specialist consultation or referral, and the use of stepwise treatment protocols. Despite evidence that these elements of chronic illness care improve patient outcomes, they are often inadequately organized and delivered.1 Table 1 Generic elements of chronic illness care included in evidence-based guidelines for 5 chronic conditions Table 2 Individualized stepped care: a scheme for managing chronic illness in primary care

Outcomes of primary care back pain patients (N = 1128) were studied at 1 year after seeking care. Changes in depression depending on outcome, and predictors of poor outcome were evaluated. Less than one back pain patient in five reported recent onset (first onset within the previous 6 months). One year after seeking care, the large majority of both recent and nonrecent-onset patients reported having back pain in the previous month (69% vs. 82%). A significant minority of both recent and nonrecent-onset patients had either a poor functional outcome (14% vs. 21%) or continuing high intensity pain without appreciable disability (10% vs. 16%). Predictors of poor outcome included pain-related disability, days in pain, lower educational attainment, and female gender. Among initially dysfunctional patients with persistent pain, one half were improved and one third had a good outcome at the 1-year follow-up. Among initially dysfunctional patients who experienced a good outcome, elevated depressive symptoms improved to normal levels at follow-up. The outcome of back pain was predicted by pain-related disability and days in pain rather than by recency of onset, so it may be more meaningful to distinguish characteristic levels of pain intensity, pain-related disability, and pain persistence than to classify patients as acute or chronic.

OBJECTIVES: To present results from an outcome evaluation of the Henry J. Kaiser Family Foundation's Community Health Promotion Grants Program (CHPGP) in the West, which represented a major community-based initiative designed to promote improved health by changing community norms, environmental conditions, and individual behavior in 11 western communities. METHODS: The evaluation design: 14 randomly assigned intervention and control communities, 4 intervention communities selected on special merit, and 4 matched controls. Data for the outcome evaluation were obtained from surveys, administered every two years at three points in time, of community leaders and representative adults and adolescents, and from specially designed surveys of grocery stores. Outcomes for each of the 11 intervention communities were compared with outcomes in control communities. RESULTS: With the exception of two intervention communities-a largely Hispanic community and a Native American reservation-we found little evidence of positive changes in the outcomes targeted by the 11 intervention communities. The programs that demonstrated positive outcomes targeted dietary behavior and adolescent substance abuse. CONCLUSIONS: Improvement of health through community-based interventions remains a critical public health challenge. The CHPGP, like other prominent community-based initiatives, generally failed to produce measurable changes in the targeted health outcomes. Efforts should focus on developing theories and methods that can improve the design and evaluation of community-based interventions.

Study Design. Review paper of outcome studies among primary care back pain patients. Objectives. To determine the short-term and long-term pain and functional outcomes of patients with back pain who are seeking treatment in primary care settings. Summary of Background Data. Back pain has been viewed as running either an acute or a chronic course, but most patients experience recurrent back pain. This review summarizes outcome studies in light of the episodic course of back pain. Methods. Studies reporting pain and functional outcome data for consecutive primary care patients with back pain were reviewed. Results. Back pain among primary care patients typically is a recurrent condition for which definitions of acute and chronic pain based on a single episode are inadequate. Because a majority of patients experience recurrences. describing only the outcome of the initial back pain episode may convey a more favorable picture of long-term outcome than warranted. For the short-term follow-up evaluation, most patients improve considerably during the first 4 weeks after seeking treatment. Sixty-six percent to 75% continue to experience at least mild back pain 1 month after seeking care. At 1 month, approximately 33% report continuing pain of at least moderate intensity, whereas 20-25% report substantial activity limitations. For the long-term follow-up (1 year or more) period, approximately 33% report intermittent or persistent pain of at least moderate intensity, one in seven continue to report back pain of severe intensity, and one in five report substantial activity limitations. Conclusion. Results from existing studies suggest that back pain among primary care patients typically runs a recurrent course characterized by variation and change, rather than an acute, self-limiting course.