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The purpose of this paper is to build on personal engagement and role theory to develop a conceptual definition of engagement to different organizational roles (job, organization, supervisor, and coworkers) and create and validate the Role-Based Engagement Scale (RBES). Data were collected from four samples (n = 1,302) of employees, including three from multiple organizations and one from an aircraft manufacturer. Results across three studies consistently support the four dimension structure of the RBES, its internal consistency, convergent, discriminant, and predictive validity based on a series of confirmatory factor analyses. The RBES is a psychometrically sound instrument that measures engagement to job, organization, supervisor, and coworkers. This instrument will provide more targeted information for human resource management (HRM) professionals tasked with developing training methods and processes to improve low-scoring dimensions of engagement, optimizing HRM interventions.
Potential effectiveness of harvest weed seed control (HWSC) systems depends upon seed shatter of the target weed species at crop maturity, enabling its collection and processing at crop harvest. However, seed retention likely is influenced by agroecological and environmental factors. In 2016 and 2017, we assessed seed shatter phenology in thirteen economically important broadleaf weed species in soybean [Glycine max (L.) Merr.] from crop physiological maturity to four weeks after physiological maturity at multiple sites spread across fourteen states in the southern, northern, and mid-Atlantic U.S. Greater proportions of seeds were retained by weeds in southern latitudes and shatter rate increased at northern latitudes. Amaranthus species seed shatter was low (0 to 2%), whereas shatter varied widely in common ragweed (Ambrosia artemisiifolia L.) (2 to 90%) over the weeks following soybean physiological maturity. Overall, the broadleaf species studied shattered less than ten percent of their seeds by soybean harvest. Our results suggest that some of the broadleaf species with greater seed retention rates in the weeks following soybean physiological maturity may be good candidates for HWSC.
As herbicide-resistant weeds become more problematic, producers will consider the use of cover crops to suppress weeds. Weed suppression from cover crops may be especially in the label-mandated buffer areas of dicamba-resistant soybean where dicamba use is not allowed. Three cover crops terminated at three timings with three herbicide strategies were evaluated for their effect on weed suppression in dicamba-resistant soybean. Delaying termination to at soybean planting, or after, and using a cereal rye or cereal rye + crimson clover increased cover crop biomass by at least 40% compared to terminating early or using a crimson clover only cover crop. Densities of problematic weed species were evaluated in early-summer prior to a blanket POST application. Plots with cereal rye had 75% less horseweed compared to crimson clover at two of four site-years. Cereal rye or the mix cover crop terminated at, or after soybean planting reduced waterhemp densities by 87% compared to early termination timings of crimson clover and the earliest termination timing of the mix at one of two site-years. Cover crops were not as effective in reducing waterhemp densities as they were in reducing horseweed densities. This difference is due to a divergence in emergence patterns; waterhemp emergence generally peaks after termination of the cover crop while horseweed emergence coincides with establishment and rapid vegetative growth of cereal rye. Cover crops alone were generally not as effective as using a high biomass cover crop combined with herbicide strategy that contained dicamba and residual herbicides. However, within label-mandated buffer areas where dicamba cannot be used, a cover crop containing cereal rye with delayed termination to at soybean planting combined with residual herbicides could be utilized to improve suppression of horseweed and waterhemp.
Seed shatter is an important weediness trait on which the efficacy of harvest weed seed control (HWSC) depends. The level of seed shatter in a species is likely influenced by agroecological and environmental factors. In 2016 and 2017, we assessed seed shatter of eight economically important grass weed species in soybean [Glycine max (L.) Merr.] from crop physiological maturity to four weeks after maturity at multiple sites spread across eleven states in the southern, northern, and mid-Atlantic U.S. From soybean maturity to four weeks after maturity, cumulative percent seed shatter was lowest in the southern U.S. regions and increased as the states moved further north. At soybean maturity, the percent of seed shatter ranged from 1 to 70%. That range had shifted to 5 to 100% (mean: 42%) by 25 days after soybean maturity. There were considerable differences in seed shatter onset and rate of progression between sites and years in some species that could impact their susceptibility to HWSC. Our results suggest that many summer annual grass species are likely not ideal candidates for HWSC, although HWSC could substantially reduce their seed output at during certain years.
A control volume based analytical method for calculating the efficiency
of flapping foil power generators was developed for single and tandem foil configurations. Ignoring unsteady effects and non-uniform pressures resulted in theoretical limits identical to the Betz (
for a single turbine) and Newman (
for tandem turbines) limits. Inclusion of unsteady flow and non-uniform pressure distributions produced theoretical efficiency maxima in excess of these limits. Simulation of single and tandem foil cases to determine the magnitude of these effects showed that the Betz limit would not be exceeded by a single foil system in practice, but that it is conceivable that a tandem foil system could exceed the Newman limit due to the strong unsteady vortex wake of the upstream turbine entraining additional energy into the path of the downstream turbine and maintaining pressures in the wake below ambient.
The prevalence of mental health conditions and national suicide rates are increasing in many countries. Lithium is widely and effectively used in pharmacological doses for the treatment and prevention of manic/depressive episodes, stabilising mood and reducing the risk of suicide. Since the 1990s, several ecological studies have tested the hypothesis that trace doses of naturally occurring lithium in drinking water may have a protective effect against suicide in the general population.
To synthesise the global evidence on the association between lithium levels in drinking water and suicide mortality rates.
The MEDLINE, Embase, Web of Science and PsycINFO databases were searched to identify eligible ecological studies published between 1 January 1946 and 10 September 2018. Standardised regression coefficients for total (i.e. both genders combined), male and female suicide mortality rates were extracted and pooled using random-effects meta-analysis. The study was registered with PROSPERO (CRD42016041375).
The literature search identified 415 articles; of these, 15 ecological studies were included in the synthesis. The random-effects meta-analysis showed a consistent protective (or inverse) association between lithium levels/concentration in publicly available drinking water and total (pooled β = −0.27, 95% CI −0.47 to −0.08; P = 0.006, I2 = 83.3%), male (pooled β = −0.26, 95% CI −0.56 to 0.03; P = 0.08, I2 = 91.9%) and female (pooled β = −0.13, 95% CI −0.24 to −0.02; P = 0.03, I2 = 28.5%) suicide mortality rates. A similar protective association was observed in the six studies included in the narrative synthesis, and subgroup meta-analyses based on the higher/lower suicide mortality rates and lithium levels/concentration.
This synthesis of ecological studies, which are subject to the ecological fallacy/bias, supports the hypothesis that there is a protective (or inverse) association between lithium intakes from public drinking water and suicide mortality at the population level. Naturally occurring lithium in drinking water may have the potential to reduce the risk of suicide and may possibly help in mood stabilisation, particularly in populations with relatively high suicide rates and geographical areas with a greater range of lithium concentration in the drinking water. All the available evidence suggests that randomised community trials of lithium supplementation of the water supply might be a means of testing the hypothesis, particularly in communities (or settings) with demonstrated high prevalence of mental health conditions, violent criminal behaviour, chronic substance misuse and risk of suicide.
Field studies were conducted in 2018 and 2019 in Arkansas, Indiana, Illinois, Missouri, and Tennessee to determine if cover-crop residue interfered with herbicides that provide residual control of Palmer amaranth and waterhemp in no-till soybean. The experiments were established in the fall with planting of cover crops (cereal rye + hairy vetch). Herbicide treatments consisted of a nontreated or no residual, acetochlor, dimethenamid-P, flumioxazin, pyroxasulfone + flumioxazin, pendimethalin, metribuzin, pyroxasulfone, and S-metolachlor. Palmer amaranth took 18 d and waterhemp took 24 d in the cover crop–alone (nontreated) treatment to reach a height of 10 cm. Compared with this treatment, all herbicides except metribuzin increased the number of days until 10-cm Palmer amaranth was present. Flumioxazin applied alone or in a mixture with pyroxasulfone were the best at delaying Palmer amaranth growing to a height of 10 cm (35 d and 33 d, respectively). The herbicides that resulted in the lowest Palmer amaranth density (1.5 to 4 times less) integrated with a cover crop were pyroxasulfone + flumioxazin, flumioxazin, pyroxasulfone, and acetochlor. Those four herbicide treatments also delayed Palmer amaranth emergence for the longest period (27 to 34 d). Waterhemp density was 7 to 14 times less with acetochlor than all the other herbicides present. Yield differences were observed for locations with waterhemp. This research supports previous research indicating that utilizing soil-residual herbicides along with cover crops improves control of Palmer amaranth and/or waterhemp.
Anthocyanins and bromelain have gained significant attention due to their antioxidative and anti-inflammatory properties. Both have been shown to improve endothelial function, blood pressure (BP) and oxygen utility capacity in humans; however, the combination of these two and the impacts on endothelial function, BP, total antioxidant capacity (TAC) and oxygen utility capacity have not been previously investigated. The purpose of this study was to investigate the impacts of a combined anthocyanins and bromelain supplement (BE) on endothelial function, BP, TAC, oxygen utility capacity and fatigability in healthy adults. Healthy adults (n 18, age 24 (sd 4) years) received BE or placebo in a randomised crossover design. Brachial artery flow-mediated dilation (FMD), BP, TAC, resting heart rate, oxygen utility capacity and fatigability were measured pre- and post-BE and placebo intake. The BE group showed significantly increased FMD, reduced systolic BP and improved oxygen utility capacity compared with the placebo group (P < 0·05). Tissue saturation and oxygenated Hb significantly increased following BE intake, while deoxygenated Hb significantly decreased (P < 0·05) during exercise. Additionally, TAC was significantly increased following BE intake (P < 0·05). There were no significant differences for resting heart rate, diastolic BP or fatigability index. These results suggest that BE intake is an effective nutritional therapy for improving endothelial function, BP, TAC and oxygen utility capacity, which may be beneficial to support vascular health in humans.
Mood disorders, i.e. major depressive disorder (MDD) and bipolar disorders, are leading sources of disability worldwide. Currently available treatments do not yield remission in approximately a third of patients with a mood disorder. This is in part because these treatments do not target a specific core pathology underlying these heterogeneous disorders. In recent years, abnormal inflammatory processes have been identified as putative pathophysiological mechanisms and treatment targets in mood disorders, particularly among individuals with treatment-resistant conditions.
In this selective review, we aimed to summarise recent advances in the field of immunopsychiatry, including emerging pathophysiological models and findings from treatment ttrials of immunomodulatory agents for both MDD and bipolar disorders.
We performed a literature review by searching Medline for clinical trials of immunomodulating agents as monotherapy or adjunctive treatments in MDD and bipolar disorders. Included studies are randomised controlled trials (RCTs), cluster RCTs or cross-over trials of immunomodulating agents that had an active comparator or a placebo-arm.
Current evidence shows an association between inflammation and mood symptoms. However, there is conflicting evidence on whether this link is causal.
Future studies should focus on identifying specific neurobiological underpinnings for the putative causal association between an activated inflammatory response and mood disorders. Results of these studies are needed before further treatment trials of immunomodulatory agents can be justified.
Vertebrates may be born highly dependent (altricial) or may rapidly gain independence (precocial). Primates are generally considered somatically precocial. However, all are at least initially helpless, and many primates have a prolonged phase of juvenility. In this chapter, we discuss how selection may influence the relative timing of appearance of morphological features (heterochrony). Newborn primate morphology offers unique insights into the roles of prenatal and postnatal growth processes, primarily because metabolic costs for growth commence a transition from the mother to the infant at this point in time. With this in mind, primates vary remarkably at birth in dental eruption and mineralization status as well as limb skeleton ossification (e.g., wrists and ankles). We also discuss evidence, still relatively scant, that at birth primates vary greatly in the degree to which neural organs (e.g., brains, eyes) have achieved adult size and proportions. In preparation for morphological descriptions to follow, the reader is introduced to the concept of modularity of growth: different parts of the skeleton or even parts of regions have different rates of growth and development.
Skeletal Anatomy of the Newborn Primate was written to broaden our knowledge of non-human primates from a comparative and developmental perspective. This chapter explains that the main focus of our book is on the inherently risky neonatal period. The “neonate,” or newborn, is considered here to be a perinatal primate of up to seven days postnatal age. However, there is no simple way to physically identify primate newborns, not in the same many have defined “infants,” based on dental maturity. This is precisely what makes the neonatal stage so interesting: primates, like most other groups of mammals, vary in how rapidly they attain physical maturity. This introductory chapter discusses terminology and methodological challenges in studying newborns.
Feeding ontogeny in primates has three stages. In utero, nutrition is gained maternally. After birth, primates suckle. We know little about functional variation in these stages. The transition to adult feeding – highlighted by weaning – varies across species. Variation is tied to many socioecological and morphological influences across primates. Primate feeding apparatus ontogeny is affected by many factors. Diet exhibits a complex relationship with the clearest signal marked by rapid dental mineralization and eruption in folivorous strepsirrhines. Mineralization varies across primates. Emergence and eruption of postcanine teeth tends to follow size in both suborders with smaller taxa showing earlier emergence, the exception being rapid eruption in some folivores. Compared to teeth, less is known about the musculoskeletal ontogeny of the feeding apparatus. Most studies compare closely related species and link musculoskeletal robustness to challenging diets. Looking forward, better understanding of primate feeding apparatus growth will require improved samples (a challenge for long-lived species) and emphasis on the evolutionary significance of feeding throughout ontogeny.
In this chapter we introduce concepts in dental development, microanatomy of the tooth germ and mineralizing crowns, and terminology relating to dental morphology. Subsequently, tooth morphology in newborn hominoids (apes and humans) is discussed based on the literature, followed by accounts of the extent of crown mineralization at birth in a newly described sample of tarsiers, Old World monkeys, New World monkeys, and strepsirrhines (lemurs and lorises). Morphology of crowns is described in all species in which the crown is completely formed at birth. The chapter ends with a brief discussion of the “perinatal” trajectory of dental development in selected primate species based on a comparison of species at different stages (fetal, neonatal, and older infant), including some at similar known ages.
Life-history theory pertains to the entirety of prenatal and postnatal ontogeny, and therefore morphology of the newborn offers an important perspective on how primates invest in their young. Generally, longer gestations yield larger neonates that are weaned later, become sexually mature later, and have larger brain masses. But can the variations in skeletal maturity are birth explained by life-history traits? Here, we examine new somatic data on 47 species of primates in light of life-history traits and modularity of growth among body regions. “Snout” length is uniformly diminutive in newborns compared to adults, although some scaling differences are already apparent at birth (relatively longer palates in strepsirrhines and tarsiers). Correlations of life-history characteristics indicate gestational length has a significant influence on facial functional matrices, with a positive correlation with permanent tooth and eye size, and a negative correlation with deciduous tooth germ size. We may as yet lack a broad enough perspective on brain size at birth, but some existing observations suggest primates preferentially prioritize prenatal brain growth over general somatic growth.
Primate locomotor development is a protracted process. We summarize the time course of locomotor development in approximately 50 primates distributed across the extant radiation. Despite substantial variance, we identify several broad trends. Primates are somewhat precocial at birth – born with their eyes open and able to strongly grasp. Locomotor onset age generally increases with body mass, although certain taxonomic groups (e.g., lemurids and cercopithecids) develop early for their size whereas others (e.g., indriids and hominids) develop relatively late. Initial locomotor movements are similar across primates and dominated by quadrupedal crawling. Only later do more specialized forms of locomotion emerge (e.g., leaping and brachiation), often in concert with functional changes in musculoskeletal anatomy (e.g., maturation of intermembral indices, center of mass position, and bony muscle leverage). We advocate viewing locomotor development as a fundamental life-history parameter, responding to the same evolutionary pressures shown to be fundamental to other aspects of primate life history (e.g., predation, resource access, body size, encephalization).