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This paper shows that K_t-minor-free (and K_{s, t}-minor-free) graphs G are subgraphs of products of a tree-like graph H (of bounded treewidth) and a complete graph K_m. Our results include optimal bounds on the treewidth of H and optimal bounds (to within a constant factor) on m in terms of the number of vertices of G and the treewidth of G. These results follow from a more general theorem whose corollaries include a strengthening of the celebrated separator theorem of Alon, Seymour, and Thomas [J. Amer. Math. Soc. 3 (1990), 801–808] and the Planar Graph Product Structure Theorem of Dujmović et al. [J. ACM 67 (2020)]. [ABSTRACT FROM AUTHOR]

Many states have legalized medical and recreational marijuana use in the past decade, which has potential consequences for roadway safety. Using a state‐level panel of heavy truck crash statistics from 2005 to 2021 and a difference‐in‐difference estimation strategy, we test whether legalization has affected crash rates. Our results show that legalization does not increase crash rates on average; however, responses are heterogeneous across states, with Colorado, New Jersey, and Washington (state) showing crash reductions, while Connecticut and Virginia saw crashes increase. These results suggest that marijuana legalization does not have a straightforward relationship with heavy truck accidents, warranting continued research and policy scrutiny. [ABSTRACT FROM AUTHOR]

The asymptotic dimension is an invariant of metric spaces introduced by Gromov in the context of geometric group theory. In this paper, we study the asymptotic dimension of metric spaces generated by graphs and their shortest path metric and show their applications to some continuous spaces. The asymptotic dimension of such graph metrics can be seen as a large scale generalisation of weak diameter network decomposition which has been extensively studied in computer science. We prove that every proper minor-closed family of graphs has asymptotic dimension at most 2, which gives optimal answers to a question of Fujiwara and Papasoglu and (in a strong form) to a problem raised by Ostrovskii and Rosenthal on minor excluded groups. For some special minorclosed families, such as the class of graphs embeddable in a surface of bounded Euler genus, we prove a stronger result and apply this to show that complete Riemannian surfaces have Assouad--Nagata dimension at most 2. Furthermore, our techniques allow us to determine the asymptotic dimension of graphs of bounded layered treewidth and graphs with any fixed growth rate, which are graph classes that are defined by purely combinatorial notions and properly contain graph classes with some natural topological and geometric flavours. [ABSTRACT FROM AUTHOR]

This monograph investigates the visual construction of migration on the U.S. southern border by the U.S. news industry. This study employs a quantitative (N = 1,050) and qualitative (N = 21) social semiotic analysis to illuminate the pervasive patterns of visual representation by three news agencies: The Associated Press, Getty Images, and Reuters. The analysis reveals levels of symbolic annihilation, social separation, and asymmetrical power dynamics that contribute to the symbolic othering of migrants. In-depth interviews with 21 photojournalists and field observation of an additional five photojournalists on the U.S.-Mexico border in Texas were conducted to analyze the factors that influence the production of images. Photojournalists are subject to myriad physical, social, and ideological influences from politicians, law enforcement, news organizations, non-governmental organizations, drug cartels, and border residents that constrain the depiction of migration. These complex conditions of production are marked by a scarcity of time, money, and autonomy that ultimately result in conventionalized imagery. The findings suggest that more comprehensive, nuanced, and humanizing accounts of migration can occur when external entities do not intercede in the interaction between photographers and migrants. Unconventional imagery, however, is no guarantee of empathetic reception from audiences who are steeped in hegemonic migration discourses produced by institutions that profoundly profit from a perpetual migration "crisis." [ABSTRACT FROM AUTHOR]

This study investigates the impact of perioperative tourniquet on skeletal muscle cells during total knee arthroplasty (TKA) and its effects on the gene expression of apoptotic, inflammatory, and angiogenic pathways. The randomized controlled trial included 44 patients undergoing TKA. The patients were randomized to undergo surgery with (n = 23) or without (n = 21) tourniquet. The tourniquet was inflated before skin incision and deflated before wound closure in the tourniquet group. Biopsies from the lateral vastus muscle were obtained from both groups before wound closure and 8 weeks after surgery. The messenger ribonucleic acid (mRNA) expression and protein levels of angiopoietin‐like 4 (ANGPTL4), Hypoxia‐inducible Factor 1α, and Vascular Endothelial Growth Factor Alpha (VEGF‐A) in the biopsies were examined by reverse transcription‐quantitative polymerase chain reaction and tissue microarray, respectively. Differences in mean values (ΔCt for mRNA expression and staining positivity for protein expression) were compared with t‐tests. The apoptotic marker BID and the angiogenic marker VEGF‐A were significantly lower in the tourniquet group compared to the control group (p = 0.03, p = 0.047). However, there was a significant upregulation of VEGF‐A 8 weeks after surgery in the tourniquet group compared to perioperative biopsies (p = 0.002), indicating persistent changes. A significant upregulation in protein expression of the angiogenic marker ANGPTL4 was found perioperatively in the tourniquet group (p = 0.02). Our results demonstrate that the angiogenic gene expression is significantly altered by the tourniquet, the effects of which might contribute to postoperative interstitial edema, increased pain, and decreased muscle strength. These effects could lead to delayed rehabilitation and ultimately reduced patient satisfaction after TKA. [ABSTRACT FROM AUTHOR]

We prove that for every path H $H$, and every integer d $d$, there is a polynomial f $f$ such that every graph G $G$ with chromatic number greater than f( t ) $f(t)$ either contains H $H$ as an induced subgraph, or contains as a subgraph the complete d $d$‐partite graph with parts of cardinality t $t$. For t = 1 $t=1$ and general d $d$ this is a classical theorem of Gyárfás, and for d = 2 $d=2$ and general t $t$ this is a theorem of Bonamy et al. [ABSTRACT FROM AUTHOR]

We prove that the vertices of every (r+1)$$ \left(r+1\right) $$‐uniform hypergraph with maximum degree Δ$$ \Delta $$ may be colored with cΔd+11/r$$ c{\left(\frac{\Delta}{d+1}\right)}^{1/r} $$ colors such that each vertex is in at most d$$ d $$ monochromatic edges. This result, which is best possible up to the value of the constant c$$ c $$, generalizes the classical result of Erdős and Lovász who proved the d=0$$ d=0 $$ case. [ABSTRACT FROM AUTHOR]

Although safety within operational systems depends on compliance with regulations, non-compliance is common in many settings. Trucking is a meaningful industry for studying operational safety compliance given that the industry is large and important, truck accidents kill thousands annually, and such accidents collectively cost the U.S. economy billions of dollars. Although the truck driving occupation is dominated by men, significant efforts are underway to recruit more women into the profession. If women are safer behind the wheel than men, increasing their ranks could improve overall safety compliance. Building on theory and evidence suggesting that men have a greater willingness to take risky actions and break rules, we used data on 22 million truck inspections from 2010 to 2022 to identify an operational safety compliance gap between men and women truckers. Overall, men were 7.4% more likely to be cited for a major violation of rules governing working hours (known as hours-of-service or HOS rules) and 13.2% more likely to have a major unsafe driving violation. We then examined whether gap changes based on carrier size and type. We found that the HOS compliance gap is smaller for small carriers (vs. large) and private carriers (vs. for-hire), but not the unsafe driving gap. Finally, we tested whether the introduction of an intervention—electronic logging devices (ELDs) that automatically record truckers' driving hours—closes the gap by increasing men's compliance. In line with predictions, differences between men and women disappeared after the mandate; but again, only for HOS compliance. Surprisingly, women had significantly more HOS violations in 2021 and 2022 than men—an outcome that may be tied to women truckers' personal safety issues. In summary, the results and additional robustness checks indicate that men committed more unsafe driving violations (e.g., speeding) than women across the entire study period, while the pattern of HOS violations varied based on external events. We conclude by highlighting possible pathways for reducing the number of collisions involving trucks and thus lowering the number of fatalities and extent of economic losses. [ABSTRACT FROM AUTHOR]

This study examined news images and captions published by The Associated Press (N = 7,455) between 2018 and 2022 to ascertain whether names were more frequently included for certain groups of people. The analysis found that people depicted in the Global North are named far more frequently than in the Global South, and that sports, entertainment, and political images include names more often than news and feature images. These pervasive patterns suggest naming has a discursive function that constructs an Other by excluding familial and cultural connotations inherent in names, forming a hierarchy through opposition, and extending social prominence for certain groups. [ABSTRACT FROM AUTHOR]

Fix k > 0, and let G be a graph, with vertex set partitioned into k subsets ("blocks") of approximately equal size. An induced subgraph of G is "transversal" (with respect to this partition) if it has exactly one vertex in each block (and therefore it has exactly k vertices). A "pure pair" in G is a pair X,Y of disjoint subsets of V (G) such that either all edges between X,Y are present or none are; and in the present context we are interested in pure pairs (X,Y) where each of X,Y is a subset of one of the blocks, and not the same block. This paper collects several results and open questions concerning how large a pure pair must be present if various types of transversal subgraphs are excluded. [ABSTRACT FROM AUTHOR]

The logistics industry in the United States has faced significant labor shortages for the last couple of decades. Women are a source of labor that has been traditionally underrepresented in the major logistics sectors, transportation, and warehousing. We study the workforce composition and potential gender wage gap across these sectors. Using data from the U.S. Census Bureau from 2003 to 2020, we show that women comprise about 4% of the workforce for truck drivers and 21% for warehouse workers. As traditionally measured by economists, there is a 17% gender wage gap among truck drivers and an 11% wage gap among warehouse workers. A regression analysis suggests that the gap is smaller for warehouse workers, which is consistent with theory that an occupation's stability and predictability can reduce or eliminate wage gaps. Further analysis is carried out on specific occupations within the logistics industry and measures the variation across truck transportation and warehousing industries. There is evidence for a declining gender wage gap across both over time, although the gap remains sizable. This paper provides insight on the trends and status of gender differences in labor outcomes in the logistics industry. [ABSTRACT FROM AUTHOR]

Introduction: Consensus recommendations bridge knowledge gaps in patellofemoral pain (PFP) research and/or clinical practice. The prevalence of PFP is 29% in elite, and 23% in amateur, female athletes.1 Consensus recommendations depend on the expertise of panelists who take part in the consensus process. To represent their target population, panels should include persons impacted by their work.2 Objectives: To assess who has been invited and whose opinions have counted towards consensus recommendations on PFP or Patellofemoral osteoarthritis (PF-OA). Study Design: A secondary analysis of data from a scoping review. Methods: The Joanna Briggs Institute Manual for Evidence Synthesis was used to map consensus statements in PFP and PF-OA. Two reviewers extracted data on the panelists including: number of panelists; definition of expertise; sex; country; country income level; and the reason they were invited to participate. Population: PFP 'experts'. Inclusion criteria -- had to be a panelist in a consensus statement making recommendations on PFP. Results: Twenty-two consensus statements were included. Thirteen (59%) focused on treatment recommendations. Nine (39%) provided a justification for why panelists were invited. Sixteen (73%) reported panelist numbers (N=365). Eleven (50%) reported panelist sex; 66% of panelists were male (111 of 169). Twelve (55%) reported panelist country; 44% (117 of 263) of panelists represented the USA or Canada. All panels included either a medical doctor or physical therapist. One consensus panel included a patient. Conclusions: PFP and PF-OA consensus statements have often failed to define who counts as an expert and the panels have lacked diversity. Experience--the metric most often used to identify experts--is not a perfect proxy for expertise.3 The patient/athlete voice has been missing from consensus panels, meaning that recommendations may not serve the athletic population who are affected by PFP. [ABSTRACT FROM AUTHOR]

Background: Tuberculous pleural effusion (TPE) is the most common form of extrapulmonary tuberculosis in many settings. The diagnostic performance of the frontline polymerase chain reaction-based GeneXpert MTB/RIF Ultra (Xpert Ultra) remains suboptimal (sensitivity of ∼30%), but data are limited. Improved diagnostic approaches are urgently needed to detect extrapulmonary tuberculosis (EPTB) in tuberculosis (TB)-endemic settings., Methods: This multicenter, prospective cohort study evaluated the diagnostic performance of a rapid (same-day) interferon gamma rapid immunosuspension assay (IRISA-TB) in patients with presumed TPE from South Africa and India. Participants underwent pleural biopsy, and testing with other available same-day diagnostic assays (adenosine deaminase [ADA], Xpert Ultra, and IRISA-TB) was concurrently undertaken. The reference standard for TB was microbiological and/or histopathological confirmation using pleural fluid and/or pleural biopsy samples., Results: A total of 217 participants with presumed TPE were recruited (106 from South Africa, 111 from India). The sensitivity of IRISA-TB (cut-point 20.5 pg/mL) was significantly better than that of Xpert Ultra (81.8% [70.4-90.2] vs 32.9% [22.1-45.1]; P < .001) and ADA at the 40 IU/mL cut-point used in India (81.8% [70.4-90.2] vs 53.8% [41.0-66.3]; P   = .002). Compared with ADA at the 30 IU/mL cut-point used in South Africa, IRISA-TB had a higher specificity (96.6% [90.3-99.3] vs 87.1% [78.6-93.2]) and a higher positive predictive value (94.7% [85.5-97.3] vs 81.8% [72.4-88.5]). The negative predictive value (NPV; rule-out value) of IRISA-TB was significantly better than that of Xpert Ultra (87.5% [83.2-93.0] vs 64.9% [61.1-68.6]; P < .001) and ADA at the 40 IU/mL cut-point (87.5% [83.2-93.0] vs 74.1% [68.7-79.0]; P < .001)., Conclusions: IRISA-TB demonstrated markedly better sensitivity and NPV than Xpert Ultra and excellent specificity for the diagnosis of TPE. These data have implications for clinical practice in TB-endemic settings., (© The Author(s) 2024. Published by Oxford University Press on behalf of Infectious Diseases Society of America.)