Moving on: Exploring the implications of leader departure and incoming temporary leaders for collective turnover and unit performance.

While leader departures from work units frequently occur within organizations and are assumed to negatively impact unit functioning, the collective reaction to a leader departure event can vary across time. While a common expectation of leader departure models is that the incoming leader is permanent, it is unclear how unit-level reactions, such as collective turnover and unit performance, might change over time in response to a departure event when the departing leader is replaced with a temporary leader. We draw on context emergent turnover (CET) theory and literature on leader departures to develop and empirically test specific hypotheses exploring relationships among leader departures, collective turnover, and unit performance over time. In addition, we examine the extent to which these relationships are influenced by the temporary status of the incoming leader. Using discontinuous growth models, we examine a longitudinal data set from 324 units within a large Latin American operation of a global direct sales company (N = 3,082 performance periods). Findings indicate that, after a leader departs, there is an immediate increase in collective turnover and that unit performance decreases over time. Further, when the incoming leader is temporary, unit performance increases briefly, but the rate of performance drops over time. Overall, our research offers insights with regard to how leader departures impact unit outcomes, as well as how long such effects last. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Expression and Variation of the Genes Involved in Rhizobium Nodulation in Red Clover.

Red clover (Trifolium pratense L.) is an important forage crop and serves as a major contributor of nitrogen input in pasture settings because of its ability to fix atmospheric nitrogen. During the legume-rhizobial symbiosis, the host plant undergoes a large number of gene expression changes, leading to development of root nodules that house the rhizobium bacteria as they are converted into nitrogen-fixing bacteroids. Many of the genes involved in symbiosis are conserved across legume species, while others are species-specific with little or no homology across species and likely regulate the specific plant genotype/symbiont strain interactions. Red clover has not been widely used for studying symbiotic nitrogen fixation, primarily due to its outcrossing nature, making genetic analysis rather complicated. With the addition of recent annotated genomic resources and use of RNA-seq tools, we annotated and characterized a number of genes that are expressed only in nodule forming roots. These genes include those encoding nodule-specific cysteine rich peptides (NCRs) and nodule-specific Polycystin-1, Lipoxygenase, Alpha toxic (PLAT) domain proteins (NPDs). Our results show that red clover encodes one of the highest number of NCRs and ATS3-like/NPDs, which are postulated to increase nitrogen fixation efficiency, in the Inverted-Repeat Lacking Clade (IRLC) of legumes. Knowledge of the variation and expression of these genes in red clover will provide more insights into the function of these genes in regulating legume-rhizobial symbiosis and aid in breeding of red clover genotypes with increased nitrogen fixation efficiency.

Isoflavone levels, nodulation and gene expression profiles of a CRISPR/Cas9 deletion mutant in the isoflavone synthase gene of red clover.

KEY MESSAGE: Isoflavones are not involved in rhizobial signaling in red clover, but likely play a role in defense in the rhizosphere. Red clover (Trifolium pratense) is a high-quality forage legume, well suited for grazing and hay production in the temperate regions of the world. Like many legumes, red clover produces a number of phenylpropanoid compounds including anthocyanidins, flavan-3-ols, flavanols, flavanones, flavones, and isoflavones. The study of isoflavone biosynthesis and accumulation in legumes has come into the forefront of biomedical and agricultural research due to potential for medicinal, antimicrobial, and environmental implications. CRISPR/Cas9 was used to knock out the function of a key enzyme in the biosynthesis of isoflavones, isoflavone synthase (IFS1). A hemizygous plant carrying a 9-bp deletion in the IFS1 gene was recovered and was intercrossed to obtain homozygous mutant plants. Levels of the isoflavones formononetin, biochanin A and genistein were significantly reduced in the mutant plants. Wild-type and mutant plants were inoculated with rhizobia to test the effect of the mutation on nodulation, but no significant differences were observed, suggesting that these isoflavones do not play important roles in nodulation. Gene expression profiling revealed an increase in expression of the upstream genes producing the precursors for IFS1, namely, phenylalanine ammonium lyase and chalcone synthase, but there were no significant differences in IFS1 gene expression or in the downstream genes in the production of specific isoflavones. Higher expression in genes involved in ethylene response was observed in the mutant plants. This response is normally associated with biotic stress, suggesting that the plants may have been responding to cues in the surrounding rhizosphere due to lower levels of isoflavones.

The ambulatory care burden of nail conditions in the United States.

BACKGROUND: Millions of Americans seek medical care for their nail conditions each year, consulting physicians of many different specialties. PURPOSE: To characterize the burden of ambulatory nail disease in the United States from 2007 to 2016. METHODS: The National Ambulatory Medical Care Survey (NAMCS) provided data on physician visits relating to nail complaints and nail diagnoses from 2007 to 2016. RESULTS: Across the estimated 21.1 million outpatient visits for nail conditions from 2007 to 2016, the ratio of females to males diagnosed with each condition was between 45.1% and 52.2%. Whites comprised over 80% of each nail diagnosis. Age group differences varied by nail diagnosis, but overall, patients aged 25-64 presented most frequently with nail complaints. The specialty consulted also varied by nail diagnosis, primarily including dermatology, family medicine, and pediatrics. LIMITATIONS: We were limited by the accuracy of diagnosis and the specialties included in NAMCS data collection. CONCLUSIONS: Patients of all ages, races, and sexes consulted physicians for the treatment of nail conditions. Onychomycosis was the most frequently diagnosed nail condition, and consultations were split between dermatologists, pediatricians, and general practitioners.

Pancreatic cancer: Stroma and its current and emerging targeted therapies.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal human malignancies with a 5-year survival rate of 8%. Dense, fibrotic stroma associated with pancreatic tumors is a major obstacle for drug delivery to the tumor bed and plays a crucial role in pancreatic cancer progression. Targeting stroma is considered as a potential therapeutic strategy to improve anti-cancer drug efficacy and patient survival. Although numerous stromal depletion therapies have reached the clinic, they add little to overall survival and are often associated with toxicity. Furthermore, increasing evidence suggests the anti-tumor properties of stroma. Its complete ablation enhanced tumor progression and reduced survival. Consequently, efforts are now focused on developing stromal-targeted therapies that normalize the reactive stroma and avoid the extremes: stromal abundance vs. complete depletion. In this review, we summarized the state of current and emerging anti-stromal targeted therapies, with major emphasis on the role of miRNAs in PDAC stroma and their potential use as novel therapeutic agents to modulate PDAC tumor-stromal interactions.

The effect of auditory and visual distracters on the useful field of view: implications for the driving task.

PURPOSE: The driving environment is becoming increasingly complex, including both visual and auditory distractions within the in-vehicle and external driving environments. This study was designed to investigate the effect of visual and auditory distractions on a performance measure that has been shown to be related to driving safety, the useful field of view. METHODS: A laboratory study recorded the useful field of view in 28 young visually normal adults (mean 22.6 +/- 2.2 years). The useful field of view was measured in the presence and absence of visual distracters (of the same angular subtense as the target) and with three levels of auditory distraction (none, listening only, listening and responding). RESULTS: Central errors increased significantly (P < 0.05) in the presence of auditory but not visual distracters, while peripheral errors increased in the presence of both visual and auditory distracters. Peripheral errors increased with eccentricity and were greatest in the inferior region in the presence of distracters. CONCLUSIONS: Visual and auditory distracters reduce the extent of the useful field of view, and these effects are exacerbated in inferior and peripheral locations. This result has significant ramifications for road safety in an increasingly complex in-vehicle and driving environment.

P2Y-like receptor, GPR105 (P2Y14), identifies and mediates chemotaxis of bone-marrow hematopoietic stem cells.

Hematopoiesis in mammals undergoes a developmental shift in location from fetal liver to bone marrow accompanied by a gradual transition from highly proliferative to deeply quiescent stem cell populations. P2Y receptors are G-protein-coupled nucleotide receptors participating in vascular and immune responses to injury. We identified a P2Y-like receptor for UDP-conjugated sugars, GPR105 (P2Y14), with restricted expression on primitive cells in the hematopoietic lineage. Anti-GPR105 antibody selectively isolated a subset of hematopoietic cells within the fetal bone marrow, but not in the fetal liver, that was enriched for G0 cell cycle status and for in vitro stem-cell-like multipotential long-term culture capability. Conditioned media from bone marrow stroma induced receptor activation and chemotaxis that was sensitive to G alpha i and anti-receptor antibody inhibition. GPR105 is a G-protein-coupled receptor identifying a quiescent, primitive population of hematopoietic cells restricted to bone marrow. It mediates primitive cell responses to specific hematopoietic microenvironments and extends the known immune system functions of P2Y receptors to the stem cell level. These data suggest a new class of receptors participating in the regulation of the stem cell compartment.