1,867 research outputs found

    Quorum-quenching activity of the AHL-lactonase from <i>Bacillus licheniformis</i> DAHB1 inhibits vibrio biofilm formation in vitro and reduces shrimp intestinal colonisation and mortality

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    Vibrio parahaemolyticus is a significant cause of gastroenteritis resulting from the consumption of undercooked sea foods and often cause significant infections in shrimp aquaculture. Vibrio virulence is associated with biofilm formation and is regulated by N-acylated homoserine lactone (AHL)-mediated quorum sensing. In an attempt to reduce vibrio colonisation of shrimps and mortality, we screened native intestinal bacilli from Indian white shrimps (Fenneropenaeus indicus) for an isolate which showed biofilm-inhibitory activity (quorum quenching) against the pathogen V. parahaemolyticus DAHP1. The AHL-lactonase (AiiA) expressed by one of these, Bacillus licheniformis DAHB1, was characterised as having a broad-spectrum AHL substrate specificity and intrinsic resistance to the acid conditions of the shrimp intestine. Purified recombinant AiiA inhibited vibrio biofilm development in a cover slip assay and significantly attenuated infection and mortality in shrimps reared in a recirculation aquaculture system. Investigation of intestinal samples also showed that AiiA treatment also reduced vibrio viable counts and biofilm development as determined by confocal laser scanning microscopy (CLSM) imaging. These findings suggest that the B. licheniformis DAHB1 quorum-quenching AiiA might be developed for use as a prophylactic treatment to inhibit or reduce vibrio colonisation and mortality of shrimps in aquaculture

    Signal-to-noise ratio analysis and evaluation of the Hadamard imaging technique

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    The signal-to-noise ratio performance of the Hadamard imaging technique is analyzed and an experimental evaluation of a laboratory Hadamard imager is presented. A comparison between the performances of Hadamard and conventional imaging techniques shows that the Hadamard technique is superior only when the imaging objective lens is required to have an effective F (focus) number of about 2 or slower

    The results of an agricultural analysis of the ERTS-1 MSS data at the Johnson Space Center

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    The initial analysis of the ERTS-1 multispectral scanner (MSS) data at the Johnson Space Center (JSC), Houston, Texas is discussed. The primary data set utilized was the scene over Monterey Bay, California, on July 25, 1972, NASA ERTS ID No. 1002-18134. It was submitted to both computerized and image interpretative processing. An area in the San Joaquin Valley was submitted to an intensive evaluation of the ability of the data to (1) discriminate between crop types and (2) to provide a reasonably accurate area measurement of agricultural features of interest. The results indicate that the ERTS-1 MSS data is capable of providing the identifications and area extent of agricultural lands and field crop types

    Surface measuring technique

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    Measurement of the surface contour of a large electrostatically formed concave reflector using a modified Foucault or knife edge test is described. The curve of the actual electrostatically formed reflector surface is compared to a curve representing a reference sphere. Measurements of surface slope and deviation are calculated every 15 cm along the reflector's horizontal and vertical diameters. Characterization of surface roughness on a small scale compared to the laser spot size at the reflector are obtained from the increased laser spot size at a distant projection screen

    Variations in older people\u27s emergency care use by social care setting: a systematic review of international evidence

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    \ua9 The Author(s) 2023. Published by Oxford University Press. BACKGROUND: Older adults\u27 use of social care and their healthcare utilization are closely related. Residents of care homes access emergency care more often than the wider older population; however, less is known about emergency care use across other social care settings. SOURCES OF DATA: A systematic review was conducted, searching six electronic databases between January 2012 and February 2022. AREAS OF AGREEMENT: Older people access emergency care from a variety of community settings. AREAS OF CONTROVERSY: Differences in study design contributed to high variation observed between studies. GROWING POINTS: Although data were limited, findings suggest that emergency hospital attendance is lowest from nursing homes and highest from assisted living facilities, whilst emergency admissions varied little by social care setting. AREAS TIMELY FOR DEVELOPING RESEARCH: There is a paucity of published research on emergency hospital use from social care settings, particularly home care and assisted living facilities. More attention is needed on this area, with standardized definitions to enable comparisons between studies

    Going the Distance Part 2: Five Ways of Teaching an Extension Course: Elive, Blackboard, Teleconference, Correspondence, and Face-to-Face

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    Remote and widely dispersed clientele in Alaska create a need for effective distance-delivery programs. Extension agents often travel via small airplane, snow machine, or boat to teach face-to-face classes in off-road communities. Effective and more cost-efficient delivery methods are needed. We taught a course for beginning farmers residing throughout Alaska using five delivery methods: Elluminate Live!, Blackboard, teleconference, correspondence, and face-to-face. We evaluated these delivery methods based on five areas: accessibility of delivery method, course completion, knowledge gain, plans to use skills, and student satisfaction. Our findings will help Extension professionals design distance-delivered programs suited to their target audience

    The Co-Occurrence of Polypharmacy and Unmet Needs for Social Care in Older People: A Systematic Review

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    \ua9 2024 Laurie E. Davies et al.Polypharmacy is common in older people who often live with disability and dependency. The number of older people living with unmet needs for social care is also believed to be rising. Polypharmacy is simple to operationalise, whilst unmet needs are not routinely identified but are known to adversely affect health and well-being. Therefore, this systematic review aimed to investigate whether polypharmacy is a marker of unmet needs for social care in older people. Sixteen databases were searched from inception to January 2021. Studies were included if they reported quantitative data for polypharmacy ("multiple medicines") in relation to unmet needs for social care ("relative or absolute") in older people ("study criteria aged ≥55 years or mean age ≥55 in the sample as a whole or stratified data for the ≥55-year age group") and were from a high-income country (defined by the World Bank). Quality was assessed using the National Institute for Health tool for observational studies. Four studies were identified from 2,549 citations, and overall, the quality of evidence was low. Some older people using multiple medications had their social care needs met, whilst others did not. However, there is a clear rationale as to why polypharmacy may be linked to unmet social care needs. Given the limited studies identified in this review, future research should explore this further. The type of unmet need measure may be important to understand the nature of the relationship between the use of multiple medications and unmet social care needs

    Characteristics of older unpaid carers in England: A study of social patterning from the English Longitudinal Study of Ageing

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    \ua9 2024 The Author(s). Published by Oxford University Press on behalf of the British Geriatrics Society.Background: A growing number of older people provide unpaid care, but contemporary research evidence on this group is limited. Aim: This study aims to describe the characteristics of older people who provide unpaid care and how these vary by socioeconomic position. Methods: Using recent information from the English Longitudinal Study of Ageing (ELSA wave 9, 2019), we analysed cross-sectional data on 1,282 unpaid carers aged ≥50. Data on sociodemographics, health, social wellbeing, care intensity and caregiver-recipient relationships were extracted. Total net non-pension wealth quintiles were used as a relative measure of socioeconomic position. Differences between the poorest and richest wealth quintiles were examined through logistic regression. Findings: Most older carers in ELSA were female and looking after another older person. Poor mental and physical health and social isolation were common, and socially patterned. Compared with carers in the middle wealth group, the poorest group were more likely to be living with the person they cared for (odds ratio (OR) 1.56 [95% confidence interval (CI) 1.03-2.36]) and more likely to experience loneliness (OR 2.29 [95% CI 1.42-3.69]), dependency (i.e.The need for help with activities of daily living) (OR 1.62 [95% CI 1.05-2.51]), chronic pain (OR 1.81 [95% CI 1.23-2.67]), a higher number of diseases (OR 1.75 [95% CI 1.15-2.65]) and fair/poor self-rated health (OR 2.59 [95% CI 1.79-3.76]). The poorest carers were also less likely to have a high quality of life (OR 0.51 [95% CI 0.33-0.80]) or be in work (OR 0.33 [95% CI 0.19-0.59]). Conclusion: Our findings suggest that financially disadvantaged unpaid carers (and their households) may have the greatest needs for intervention and support. Focussing resources on this group has potential to address social inequalities

    Water Entry of Spheres at Various Contact Angles

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    It is well known that the water entry of a sphere causes cavity formation above a critical impact velocity as a function of the solid-liquid contact angle (Duez et al. 2007). Using a rough sphere with a contact angle of 120â—¦, Aristoff & Bush (2009) showed that there are four different cavity shapes dependent on the Bond and Weber numbers (i.e., quasi-static, shallow, deep and surface). We experimentally alter the Bond number, Weber number and contact angle of smooth spheres and find two key additions to the literature: 1) Cavity shape also depends on the contact angle; 2) the absence of a splash crown at low Weber number results in cavity formation below the predicted critical velocity. In addition, we find an alternate scaling for the Bond and Weber numbers that predicts cavity shapes for various impacting bodies (e.g., spheres, multi-droplet streams and jets) on the same regime diagram, thus, merging the often separated studies of solid-liquid and liquid-liquid impact in the literature
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