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Ixodes scapularis is a blood-feeding obligate ectoparasite responsible for transmitting the Lyme disease (LD) agent, Borrelia burgdorferi. During the feeding process, I. scapularis injects B. burgdorferi into the host along with its saliva, facilitating the transmission and colonization of the LD agent. Tick calreticulin (CRT) is one of the earliest tick saliva proteins identified and is currently utilized as a biomarker for tick bites. Our recent findings revealed elevated levels of CRT in the saliva proteome of B. burgdorferi-infected I. scapularis nymphs compared to uninfected ticks. Differential precipitation of proteins (DiffPOP) and LC-MS/MS analyses were used to identify the interactions between Ixs (I. scapularis) CRT and human plasma proteins and further explore its potential role in shielding B. burgdorferi from complement killing. We observed that although yeast-expressed recombinant (r) IxsCRT binds to the C1 complex (C1q, C1r, and C1s), the activator of complement via the classical cascade, it did not inhibit the deposition of the membrane attack complex (MAC) via the classical pathway. Intriguingly, rIxsCRT binds intermediate complement proteins (C3, C5, and C9) and reduces MAC deposition through the lectin pathway. Despite the inhibition of MAC deposition in the lectin pathway, rIxsCRT did not protect a serum-sensitive B. burgdorferi strain (B314/pBBE22Luc) from complement-induced killing. As B. burgdorferi establishes a local dermal infection before disseminating to secondary organs, it is noteworthy that rIxsCRT promotes the replication of B. burgdorferi in culture. We hypothesize that rIxsCRT may contribute to the transmission and/or host colonization of B. burgdorferi by acting as a decoy activator of complement and by fostering B. burgdorferi replication at the transmission site. [ABSTRACT FROM AUTHOR]

Background: Videoconferencing-based treatments have shown great potential in increasing engagement and compliance by decreasing the barriers of time and distance. In general, employees tend to experience a lot of stress, but find it difficult to visit a clinic during office hours.Objective: The purpose of this study was to investigate the effectiveness of a mobile videoconference-based intervention for stress reduction and resilience enhancement in employees.Methods: In total, 81 participants were randomly allocated to one of the three conditions: mobile videoconferencing, in-person, and self-care; of these, 72 completed the study. All participants underwent assessment via self-reported questionnaires before, immediately after, and 1 month after the intervention. Intervention lasted for 4 weeks and consisted of elements of cognitive behavioral therapy, positive psychology, and meditation. Changes in clinical variables regarding stress and resilience across time were compared between treatment conditions.Results: There were significant condition × time effects on variables measuring perceived stress, resilience, emotional labor, and sleep, demonstrating significantly differential effects across time according to treatment condition. Moreover, there were significant effects of condition on perceived stress and occupational stress. There were no significant differences in any variable between the mobile videoconferencing and in-person conditions at 1 month after the intervention.Conclusions: Results indicate that both mobile videoconferencing and in-person interventions were comparably effective in decreasing stress and enhancing resilience. Further studies with a larger sample size and a longer follow-up period are warranted to investigate the long-term effect of mobile videoconferencing interventions.Trial Registration: ClinicalTrials.gov identifier NCT03256682; https://clinicaltrials.gov/ct2/show/NCT03256682 (Archived by WebCite at http://www.webcitation.org/71W77bwnR). [ABSTRACT FROM AUTHOR]

Abstract: Experiments in low-strain-rate methane–air counterflow diffusion flames diluted with nitrogen have been conducted to study flame extinction behavior and edge flame oscillation in which flame length is less than the burner diameter and thus lateral conductive heat loss, in addition to radiative loss, could be high at low global strain rates. The critical mole fraction at flame extinction is examined in terms of velocity ratio and global strain rate. Onset conditions of the edge flame oscillation and the relevant modes are also provided with global strain rate and nitrogen mole fraction in the fuel stream or in terms of fuel Lewis number. It is observed that flame length is intimately relevant to lateral heat loss, and this affects flame extinction and edge flame oscillation considerably. Lateral heat loss causes flame oscillation even at fuel Lewis number less than unity. Edge flame oscillations, which result from the advancing and retreating edge flame motion of the outer flame edge of low-strain-rate flames, are categorized into three modes: a growing, a decaying, and a harmonic-oscillation mode. A flame stability map based on the flame oscillation modes is also provided for low-strain-rate flames. The important contribution of lateral heat loss even to edge flame oscillation is clarified finally. [Copyright &y& Elsevier]

The functional characteristics of a beta-cyclodextrin glucanotransferase (CGTase) excreted from alkalophilic Bacillus sp. BL-31 that is highly specific for the intermolecular transglycosylation of bioflavonoids were investigated. The new beta-CGTase showed high specificities for glycosyl acceptor bioflavonoids, including naringin, rutin, and hesperidin, and especially naringin. The transglycosylation of naringin into glycosyl naringin was then carried out under the conditions of 80 units of CGTase per gram of maltodextrin, 5 g/l of naringin, 25 g/l of maltodextrin, and 1 mM Mn2+ ion at 40 degrees C for 6 h, resulting in a high conversion yield of 92.1%.