Resistance to Bipyridyls Mediated by the TtgABC Efflux System inPseudomonas putidaKT2440

Resistance-nodulation-division (RND) transporters are involved in antibiotic resistance and have a broad substrate specificity. However, the physiological significance of these efflux pumps is not fully understood. Here, we have investigated the role of the RND system TtgABC in resistance to metal ion chelators in the soil bacteriumPseudomonas putidaKT2440. We observed that the combined action of an RND inhibitor and the chelator 2,2'-bipyridyl inhibited bacterial growth. In addition, the deletion ofttgBmade the strain susceptible to 2,2'-bipyridyl and natural bipyridyl derivatives such as caerulomycin A, indicating that TtgABC is required for detoxification of compounds of the bipyridyl family. Searching for the basis of growth inhibition by bipyridyls, we found reduced adenosine triphosphate (ATP) levels in thettgBmutant compared to the wild type. Furthermore, the expression of genes related to iron acquisition and the synthesis of the siderophore pyoverdine were reduced in the mutant compared to the wild type. Investigating the possibility that 2,2'-bipyridyl in thettgBmutant mediates iron accumulation in cells (which would cause the upregulation of genes involved in oxidative stressviathe Fenton reaction), we measured the expression of genes coding for proteins involved in intracellular iron storage and the response to oxidative stress. However, none of the genes was significantly upregulated. In a further search for a possible link between 2,2'-bipyridyl and the observed phenotypes, we considered the possibility that the ion chelator limits the intracellular availability of metabolically important metal ions. In this context, we found that the addition of copper restores the growth of thettgBmutant and the production of pyoverdine, suggesting a relationship between copper availability and iron acquisition. Taken together, the results suggest that detoxification of metal chelating compounds of the bipyridyl family produced by other bacteria or higher ordered organisms is one of the native functions of the RND efflux pump TtgABC. Without the efflux pump, these compounds may interfere with cell ion homeostasis with adverse effects on cell metabolism, including siderophore production. Finally, our results suggest that TtgABC is involved in resistance to bile salts and deoxycholate

Physical Activity Behavior Comparisons Between Adults With and Without Type 1 Diabetes

Physical activity (PA) is a widely accepted strategy to manage chronic diseases like type 1 diabetes; however, unique PA barriers likely result in lower PA levels among person(s) with type 1 diabetes (PWT1D), compared to person(s) without type 1 diabetes (PWOT1D). The integrated theory of health behavior change (ITHBC) (i.e., knowledge/beliefs, self-regulation, and self-management) provides a helpful framework for understanding PA and other health behaviors. This research aimed to determine differences in PA between adult PWT1D and PWOT1D, and characterize their PA-related behaviors using the ITHBC. Participants (N = 90; 86.7% female, 90% white) were recruited via social media and university listserv to complete an online questionnaire. Questions addressed demographics, anthropometrics, diabetes status, and PA-related behaviors. Participants were matched for race, gender, age, and body mass index. PA and related behaviors were compared between PWT1D and PWOT1D using independent samples t-tests and chi-square-tests. No significant differences were found between PWT1D and PWOT1D for weekly minutes of moderate- or vigorous-aerobic PA, or weekly days of muscle-strengthening PA (p \u3e 0.05). Fifty-one percent of PWT1D and 53.3% of PWOT1D reported enough activity to meet PA guidelines. Almost twice as many PWT1D meeting PA guidelines reported using goal setting, a self-regulation behavior, compared to those who did not meet guidelines (82.6% versus 45.5%, p = 0.009). Targeting PA-related behaviors within ITHBC constructs may help reinforce or influence PA behaviors. These findings can inform future behavior change interventions with PWT1D that focus on educational practices for type 1 diabetes educators or healthcare providers for PWT1D so they can better aid patients

The ABC transporter family efflux pump PvdRT‐OpmQ of Pseudomonas putida KT2440: purification and initial characterization

Tripartite efflux systems of the ABC-type family transport a variety of substrates and contribute to the antimicrobial resistance of Gram-negative bacteria. PvdRT-OpmQ, a member of this family, is thought to be involved in the secretion of the newly synthesized and recycled siderophore pyoverdine in Pseudomonas species. Here, we purified and characterized the inner membrane component PvdT and the periplasmic adapter protein PvdR of the plant growth-promoting soil bacterium Pseudomonas putida KT2440. We show that PvdT possesses an ATPase activity that is stimulated by the addition of PvdR. In addition, we provide the first biochemical evidence for direct interactions between pyoverdine and PvdRT

The Archive Query Log: Mining Millions of Search Result Pages of Hundreds of Search Engines from 25 Years of Web Archives

The Archive Query Log (AQL) is a previously unused, comprehensive query log collected at the Internet Archive over the last 25 years. Its first version includes 356 million queries, 166 million search result pages, and 1.7 billion search results across 550 search providers. Although many query logs have been studied in the literature, the search providers that own them generally do not publish their logs to protect user privacy and vital business data. Of the few query logs publicly available, none combines size, scope, and diversity. The AQL is the first to do so, enabling research on new retrieval models and (diachronic) search engine analyses. Provided in a privacy-preserving manner, it promotes open research as well as more transparency and accountability in the search industry.Comment: SIGIR 2023 resource paper, 13 page

Contrast estimation for parametric stationary determinantal point processes

We study minimum contrast estimation for parametric stationary determi-nantal point processes. These processes form a useful class of models for repulsive (or regular, or inhibitive) point patterns and are already applied in numerous statistical applications. Our main focus is on minimum contrast methods based on the Ripley's K-function or on the pair correlation function. Strong consistency and asymptotic normality of theses procedures are proved under general conditions that only concern the existence of the process and its regularity with respect to the parameters. A key ingredient of the proofs is the recently established Brillinger mixing property of stationary determinantal point processes. This work may be viewed as a complement to the study of Y. Guan and M. Sherman who establish the same kind of asymptotic properties for a large class of Cox processes, which in turn are models for clustering (or aggregation)

Транспортная логистика: проблемы и перспективы развития в таможенном деле

Выпускная квалификационная работа посвящена исследованию транспортной логистике в таможенном деле. Целью данной работы является комплексный анализ факторов, механизмов и проблем трансформации таможенной логистики в глобальной торговой системе и обоснование направлений адаптации таможенной логистики России в условиях либерализации международной торговли. Задачи: •Понятие, виды, функции логистики •Задачи транспортной логистики •Сущность таможенной логистики •Проблемы становления таможенной логистики •Ключевые проблемы таможенной логистики •Перспективы развития таможенной логистики. Объектом исследования является процесс формирования и реализации таможенной логистики в глобальной торговой системе.The final qualifying work is devoted to the study of transport logistics in the customs business. The purpose of this work is a comprehensive analysis of the factors, mechanisms and problems of the transformation of customs logistics in the global trading system and the rationale for adapting the customs logistics of Russia in the context of the liberalization of international trade

Электропривод ленточного конвейера обогатительной фабрики

Цель работы-разработка частотно регулируемого электропривода конвейера удовлетворяющего техническим условиям. В работе был произведён расчет и выбор приводного двигателя; преобразователя частоты, а также определенны параметры силовой цепи. Обоснован выбор способа управления, рассчитаны механические и электромеханические характеристики. Методом имитационного моделирования исследованы переходные процессы в основных режимах работы.The purpose of the operation is to develop a frequency controlled electric drive of a conveyor meeting the specifications. In operation, the calculation and selection of the drive engine was made; Frequency converter, as well as defined parameters of power circuit. The choice of control method is justified, mechanical and electromechanical characteristics are calculated. By means of simulation transient processes in the main operating modes are investigated