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OBJECTIVE: To describe differences in agentic (achievement) and communal (relationship) terms in letters of recommendation (LORs) for pediatric residency candidates by applicant and letter writer demographics and to examine if LOR language is associated with interview status. METHODS: A random sample of applicant profiles and LORs submitted to one institution were analyzed from the 2020--21 Match. Letters of recommendation text was inputted into a customized natural language processing application which determined the frequency of agentic and communal words in each LOR. Neutral LORs were defined as having < 5% surplus of agentic or communal terms. RESULTS: We analyzed 2094 LORs from 573 applicants: 78% were women, 24% were under-represented in medicine (URiM), and 39% were invited to interview. Most letter writers were women (55%) and of senior academic rank (49%). Overall, 53% of LORs were agency biased, 25% communal biased, and 23% neutral. There was no difference in agency and communally biased LORs by an applicant's gender (men 53% agentic vs women 53% agentic, P = .424), race or ethnicity (non-URiM 53% agentic vs URiM 51% agentic, P = .631). Male letter writers used significantly more agentic terms (8.5%) compared to women (6.7% agentic) or writers of both genders (3.1% communal) (P = .008). Applicants invited to interview were more likely to have a neutral LOR; however, no significant association existed between language and interview status. CONCLUSIONS: No significant differences in language were found by applicant gender or race among pediatric residency candidates. Identifying potential biases within pediatric residency selection processes is important in creating an equitable approach to application review. [ABSTRACT FROM AUTHOR]

Despite the well-established association between chronic inflammatory conditions and pulmonary embolism(PE), previous investigations of the relationship between Dermatomyositis(DM) and Polymyositis(PM) with PE were scarce and have been subject to significant limitations, including small sample sizes and failure to account for potential confounders. To investigate the correlation between DM/PM and PE, as well as assessing the impact of serologic status, myonecrosis, and inflammation markers on this relationship. In this large, nationwide population-based study, we used the Clalit Health Services medical database and extracted all DM/PM patients who were first diagnosed between 1 January 2002 to 31 December 2018 and compared them with age and gender matched controls in a ratio of 1:5. Serological and laboratory values were obtained for each patient. Rates of PE were compared between groups using multivariate models. The study included 1557 DM patients with 7633 controls, and 528 PM patients with 2560 controls. Compared with matched controls, the rates of PE were significantly higher in the DM/PM group, PM patients(2.8 % vs 0.5 % in controls, OR = 5.73, p < 0.001), DM patients(1.2 % vs 0.3 % in controls, OR = 3.42, p < 0.001). APLA seropositivity was significantly more prevalent in DM/PM patients compared with their matched controls, PM patients(10.8 % vs 2.7 % in controls, p < 0.001), DM patients(7.9 % vs 1.6 % in controls, p < 0.001). APLA seropositivity had a synergistic effect for PE in the DM/PM(OR = 23.18, p < 0.001). DM and PM are associated with higher rates of PE. Furthermore, patients with DM/PM demonstrate a significantly higher prevalence APLA which act as a potentiator of thrombosis in these patients. • This study from Israel examined the risk of pulmonary embolism (PE) in patients with dermatomyositis (DM) and polymyositis (PM). • Using a large cohort of over 12,000 DM/PM patients and matched controls, the study found that DM and PM patients had a higher risk of developing PE. • DM/PM patients were more likely to have APLA seropositive tests, and those were at an even greater risk of developing PE. • These findings suggest the importance of screening DM/PM populations for APLA and potentially considering prophylactic treatment for PE. • These results could have important clinical implications and may prompt further research to improve care and outcomes for DM and PM patients. [ABSTRACT FROM AUTHOR]

TmaR, the only known pole-localizer protein in Escherichia coli , was shown to cluster at the cell poles and control localization and activity of the major sugar regulator in a tyrosine phosphorylation-dependent manner. Here, we show that TmaR assembles by phase separation (PS) via heterotypic interactions with RNA in vivo and in vitro. An unbiased automated mutant screen combined with directed mutagenesis and genetic manipulations uncovered the importance of a predicted nucleic-acid-binding domain, a disordered region, and charged patches, one containing the phosphorylated tyrosine, for TmaR condensation. We demonstrate that, by protecting flagella-related transcripts, TmaR controls flagella production and, thus, cell motility and biofilm formation. These results connect PS in bacteria to survival and provide an explanation for the linkage between metabolism and motility. Intriguingly, a point mutation or increase in its cellular concentration induces irreversible liquid-to-solid transition of TmaR, similar to human disease-causing proteins, which affects cell morphology and division. [Display omitted] • TmaR undergoes phase separation (PS) via heterotypic interactions with RNA • Combined biased and unbiased mutagenesis revealed the requisites for TmaR PS • TmaR condensates protect flagellar mRNAs, thus controlling flagella formation • TmaR may transition from liquid to solid similar to disease-causing proteins TmaR is a bacterial pole localizer that regulates sugar metabolism. Szoke et al. show that TmaR clusters are formed by phase separation. By protecting flagella-related transcripts, TmaR controls flagella biogenesis and motility. Their results show that phase separation is important for bacterial survival and explain the linkage between metabolism and motility. [ABSTRACT FROM AUTHOR]

A coupled Gompertz-like system of delay differential equations is considered. We prove the existence of T -periodic solutions under resonance assuming a Lazer–Leach type condition. [ABSTRACT FROM AUTHOR]

Scanning microwave impedance microscopy (sMIM) is an emerging technique that has the potential to displace conventional scanning capacitance microscopy (SCM), and other electrical scanning probe microscopy (SPM) techniques, for the profiling of dopants in semiconductor samples with sub-micron spatial resolution. In this work, we consider the practical application of sMIM for quantitative measurement of the dopant concentration profile in production semiconductor devices. We calibrate the sMIM using a doped calibration sample prior to performing the measurements on an “unknown” production device. We utilize nanoscale C-V curves to establish a calibration curve for both n- and p-type carriers in a single reference and apply the calibration curve to an “unknown” device presenting the measurements in units of doping concentration. The calibrated results are compared to SRP measurements on the same area of the device. [ABSTRACT FROM AUTHOR]

Bacterial cells are intricately organized, despite the lack of membrane-bounded organelles. The extremely crowded cytoplasm promotes macromolecular self-assembly and formation of distinct subcellular structures, which perform specialized functions. For example, the cell poles act as hubs for signal transduction complexes, thus providing a platform for the coordination of optimal cellular responses to environmental cues. Distribution of macromolecules is mostly mediated via specialized transport machineries, including the MreB cytoskeleton. Recent evidence shows that RNAs also specifically localize within bacterial cells, raising the possibility that gene expression is spatially organized. Here we review the current understanding of where things are in bacterial cells and discuss emerging questions that need to be addressed in the future. [ABSTRACT FROM AUTHOR]

A substitution is introduced which exploits the parameters of the high-order delayed linear non-autonomous models and consequently allows the use of the M -matrix methods for the stability analysis. To demonstrate the efficacy of the proposed algorithm we obtain explicit and practical stability conditions for the second and third order non-autonomous delayed models. [ABSTRACT FROM AUTHOR]

Hfq, an Sm-like protein and the major RNA chaperone in E. coli , has been shown to distribute non-uniformly along a helical path under normal growth conditions and to relocate to the cell poles under certain stress conditions. We have previously shown that Hfq relocation to the poles is accompanied by polar accumulation of most small RNAs (sRNAs). Here, we show that Hfq undergoes RNA-dependent phase separation to form cytoplasmic or polar condensates of different density under normal and stress conditions, respectively. Purified Hfq forms droplets in the presence of crowding agents or RNA, indicating that its condensation is via heterotypic interactions. Stress-induced relocation of Hfq condensates and sRNAs to the poles depends on the pole-localizer TmaR. Phase separation of Hfq correlates with its ability to perform its posttranscriptional roles as sRNA-stabilizer and sRNA-mRNA matchmaker. Our study offers a spatiotemporal mechanism for sRNA-mediated regulation in response to environmental changes. [Display omitted] • Hfq undergoes phase separation via heterotypic interactions with RNA • Hfq forms condensates of different material state in stressed and unstressed cells • Phase separation of Hfq depends on the pole-localizer TmaR • Phase separation of Hfq correlates with its activity as an RNA chaperone Hfq is an RNA chaperon that binds to small regulatory RNAs (sRNAs) and matches them with mRNAs, thus regulating their fate. Goldberger et al. show that, upon stress, Hfq undergoes phase separation and condenses at the cell poles with RNA. This process is important for its role as sRNA-mRNA matchmaker. [ABSTRACT FROM AUTHOR]

An N -dimensional generalization of Nicholson's equation is analyzed. We consider a model including multiple delays, nonlinear coefficients and a nonlinear harvesting term. Inspired by previous results in this subject, we obtain sufficient conditions to guarantee strong and uniform persistence. Furthermore, under extra suitable hypotheses we prove the existence of T -periodic solutions and, reversing the prior conditions in a convenient manner, we show that the zero is a global attractor. [ABSTRACT FROM AUTHOR]

Abstract: Existence, uniqueness, and multiplicity properties are established via a variational formulation for a Painlevé II model subject to radiation boundary conditions in two-ion electrodiffusion. Numerical experiments using an adapted shooting method are also presented to support the theoretical results. [Copyright &y& Elsevier]

This study investigates the association between exposure to ambient NOx and SO2 originating from power plant emissions and prevalence of obstructive pulmonary disease and related symptoms. The Orot Rabin coal-fired power plant is the largest power generating facility in the Eastern Mediterranean. Two novel methods assessing exposure to power plant-specific emissions were estimated for 2244 participants who completed the European Community Respiratory Health Survey. The “source approach” modeled emissions traced back to the power plant while the “event approach” identified peak exposures from power plant plume events. Respiratory symptoms, but not prevalence of asthma and COPD, were associated with estimates of power plant NOx emissions. The “source approach” yielded a better estimate of exposure to power plant emissions and showed a stronger dose–response relationship with outcomes. Calculating the portion of ambient pollution attributed to power plants emissions can be useful for air quality management purposes and targeted abatement programs. [Copyright &y& Elsevier]

Abstract: We study the existence of solutions for the nonlinear second order elliptic system , where with bounded. Using topological degree methods, we prove an existence result under a geometric condition on . Moreover, we analyze the particular case of an isolated repulsive singularity: under a Nirenberg type condition, we prove the existence of a sequence of solutions of appropriate approximated problems that converges to a generalized solution. [Copyright &y& Elsevier]

Abstract: We give sufficient and necessary conditions for the existence of at least one positive -periodic solution for a generalized Nicholson’s blowflies model with a nonlinear harvesting term. Our results extend those of the previous work Li and Du (2008) . [Copyright &y& Elsevier]

Abstract: Mathematical models of angiogenesis, pioneered by Hahnfeldt, are under study. To enrich the dynamics of three models, we introduced biologically motivated time-varying delays. All models under study belong to a special class of nonlinear nonautonomous delay differential systems with non-Lipschitz nonlinearities. Explicit conditions for the existence of positive global solutions and the equilibria solutions were obtained. Based on a notion of an -matrix, new results are presented for the global stability of the system and were used to prove local stability of one model. For a local stability of a second model, the recent result for a Lienard-type second-order differential equation with delays was used. It was shown that models with delays produce a complex and nontrivial dynamics. Some open problems are presented for further studies. [Copyright &y& Elsevier]

Abstract: To enrich the dynamics of mathematical models of angiogenesis, all mechanisms involved are time-dependent. We also assume that the tumor cells enter the mechanisms of angiogenic stimulation and inhibition with some delays. The models under study belong to a special class of nonlinear nonautonomous systems with delays. Explicit sufficient and necessary conditions for the existence of the positive periodic solutions were obtained via topological methods. Numerical examples illustrate our findings. Some open problems are presented for further studies. [Copyright &y& Elsevier]

Abstract: A two-point Neumann boundary value problem for a two-ion electro-diffusion model reducible to the Painlevé II equation is investigated. The problem is unconventional in that the model equation involves yet-to-be-determined boundary values of the solution. In prior work by Thompson, the existence of a solution was established subject to an inequality on the physical parameters. Here, a two-dimensional shooting method is used to show that this restriction may be removed. A practical algorithm for the solution of the boundary value problem is presented in an appendix. [Copyright &y& Elsevier]

Abstract: We study a parabolic problem arising in Financial Mathematics. Under suitable conditions, we prove the existence and uniqueness of solutions in a general domain using the method of upper and lower solutions and a diagonal argument. [Copyright &y& Elsevier]

Abstract: Two types of boundary value problem on the infinite half-line are investigated for a class of generalised Painlevé II equations. Existence results are obtained via the method of upper and lower solutions together with a diagonal argument. [Copyright &y& Elsevier]

Abstract: We study the existence of periodic solutions for a nonlinear system of th-order differential equations on time scales. Assuming a suitable Nirenberg-type condition, we prove the existence of at least one solution of the problem using Mawhin’s coincidence degree. [Copyright &y& Elsevier]