Combating infectious diseases in aquaculture with an original probiotic product

Oyster production in Rhode Island accounts for over $2.5 million in annual revenue, making it the top aquaculture product in the state. However, larval tank infections significantly constrain production and create substantial economic losses for commercial hatcheries. In most cases antibiotics may not be used to prevent or treat larval tank infections. A probiotic, or beneficial microbe which competes with pathogens, is a safer and “green” approach to preventing infections. Vibriosis, a common cause of oyster larval mortality, is the result of Vibrio species infections. Previous studies have shown that a native Rhode Island microbe, Bacillus pumilus RI06-95, protects oyster larvae against infection by the pathogen Vibrio tubiashii RE22. In this study, a freeze-dried formulation of this probiotic agent was evaluated for use in commercial hatchery tanks. Stability, dispersion and pilot-scale hatchery studies were performed to evaluate this product. A viability analysis of the freeze-dried product over time revealed that when stored at 4 ºC, the product will maintain viable probiotic cells at greater than the minimum effective concentration, 108 CFU/mL per single-use tube, for at least two months. The dispersion of this product in seawater was investigated using light microscopy, and qualitatively showed that the product readily and rapidly disperses within 30 seconds, without any shaking or added energy. A pilot-scale hatchery study revealed that the freeze-dried product increased survival of three-day-old and eight-day-old larvae after challenged with Vibrio tubiashii RE22 by 26 % (± 15 %) and 47 % (± 28 %) respectively, compared to larvae which received no probiotic treatment. Based on these results, we conclude that our freeze-dried formulation of Bacillus pumilus RI06-95 is a stable, easy-to-use, safe and efficacious probiotic product for sustainable oyster aquaculture

Correcting for T1 bias in Magnetization Transfer Saturation (MTsat) Maps Using Sparse-MP2RAGE

Purpose: Magnetization transfer saturation (MTsat) mapping is commonly used to examine the macromolecular content of brain tissue. This study compared variable flip angle (VFA) T1 mapping against compressed sensing (cs)MP2RAGE T1 mapping for accelerating MTsat imaging. Methods: VFA, MP2RAGE and csMP2RAGE were compared against inversion recovery (IR) T1 in a phantom at 3 Tesla. The same 1 mm VFA, MP2RAGE and csMP2RAGE protocols were acquired in four healthy subjects to compare the resulting T1 and MTsat. Bloch-McConnell simulations were used to investigate differences between the phantom and in vivo T1 results. Finally, ten healthy controls were imaged twice with the csMP2RAGE MTsat protocol to quantify repeatability. Results: The MP2RAGE and csMP2RAGE protocols were 13.7% and 32.4% faster than the VFA protocol, respectively. All approaches provided accurate T1 values (<5% difference) in the phantom, but the accuracy of the T1 times was more impacted by differences in T2 for VFA than for MP2RAGE. In vivo, VFA generated longer T1 times than MP2RAGE and csMP2RAGE. Simulations suggest that the bias in the T1 values between VFA and IR-based approaches (MP2RAGE and IR) could be explained by the MT-effects from the inversion pulse. In the test-retest experiment, we found that the csMP2RAGE has a minimum detectable change of 3% for T1 mapping and 7.9% for MTsat imaging. Conclusions: We demonstrated that csMP2RAGE can be used in place of VFA T1 mapping in an MTsat protocol. Furthermore, a shorter scan time and high repeatability can be achieved using the csMP2RAGE sequence.Comment: 23 pages, 7 figures, 2 table

Optimization of acquisition parameters for cortical inhomogeneous magnetization transfer (ihMT) imaging using a rapid gradient echo readout

Purpose: Imaging biomarkers with increased myelin specificity are needed to better understand the complex progression of neurological disorders. Inhomogeneous magnetization transfer (ihMT) imaging is an emergent technique that has a high degree of specificity for myelin content but suffers from low signal-to-noise ratio (SNR). This study used simulations to determine optimal sequence parameters for ihMT imaging for use in high-resolution cortical mapping. Methods: MT-weighted cortical image intensity and ihMT SNR were simulated using modified Bloch equations for a range of sequence parameters. The acquisition time was limited to 4.5 min/volume. A custom MT-weighted RAGE sequence with center-out k-space encoding was used to enhance SNR at 3 Tesla. Pulsed MT imaging was studied over a range of saturation parameters and the impact of the turbo-factor on effective ihMT was investigated. 1 mm isotropic ihMTsat maps were generated in 25 healthy adults using an optimized protocol. Results: Greater SNR was observed for larger number of bursts consisting of 6-8 saturation pulses each, combined with a high readout turbo-factor. However, that protocol suffered from a point spread function that was more than twice the nominal resolution. For high-resolution cortical imaging, we selected a protocol with a higher effective resolution at the cost of a lower SNR. We present the first group-average ihMTsat whole-brain map at 1 mm isotropic resolution. Conclusion: This study presents the impact of saturation and excitation parameters on ihMTsat SNR and resolution. We demonstrate the feasibility of high-resolution cortical myelin imaging using ihMTsat in less than 20 minutes

Student use of electronic information services in further education

This paper presents a profile of user behaviour in relation to the use of electronic information services (EIS), information skills, and the role of training and wider learning experiences in UK further education colleges. The research was conducted under the JISC User Behaviour Monitoring and Evaluation Framework. Work was conducted in two strands, by two project teams, JUSTEIS and JUBILEE. JUSTEIS profiled the use of EIS and assessed the availability of EIS. JUBILEE objectives focussed on understanding the barriers and enablers, with a view to developing success criteria. JUSTEIS used a multi-stage stratified sampling process, and collected data from 270 respondents from 17 departments in the baseline survey (2001/2002). JUBILEE conducted in-depth fieldwork in five institutions and snapshot fieldwork in 10 institutions, collecting data from 528 respondents. Information skills and experience develop across work, home and study. There is a growing use of EIS in curriculum, but practice varies between institutions and disciplines. Tutors express concern about student's ability to evaluate and use the information that they find. Assignments can promote EIS use. The main categories of EIS used by students are search engines and organisational web sites. Search engines are the preferred search tools and search strategies are basic. Information skills are acquired through a variety of routes, with peer instruction, surfing and personal experience, instruction from tutors, and LIS induction and training all making an important contribution. The solutions to improving students’ information skills may include use of the Virtual Training Suites, but librarians need to adopt different roles in promoting and evaluating use of such tools

Dual-encoded magnetization transfer and diffusion imaging and its application to tract-specific microstructure mapping

We present a novel dual-encoded magnetization transfer (MT) and diffusion-weighted sequence and demonstrate its potential to resolve distinct properties of white matter fiber tracts at the sub-voxel level. The sequence was designed and optimized for maximal MT contrast efficiency. The resulting whole brain 2.6 mm isotropic protocol to measure tract-specific MT ratio (MTR) has a scan time under 7 minutes. Ten healthy subjects were scanned twice to assess repeatability. Two different analysis methods were contrasted: a technique to extract tract-specific MTR using Convex Optimization Modeling for Microstructure Informed Tractography (COMMIT), a global optimization technique; and conventional MTR tractometry. The results demonstrate that the tract-specific method can reliably resolve the MT ratios of major white matter fiber pathways and is less affected by partial volume effects than conventional multi-modal tractometry. Dual-encoded MT and diffusion is expected to both increase the sensitivity to microstructure alterations of specific tracts due to disease, ageing or learning, as well as lead to weighted structural connectomes with more anatomical specificity.Comment: 26 pages, 7 figure

Screening the PRISM Library against Staphylococcus aureus Reveals a Sesquiterpene Lactone from Liriodendron tulipifera with Inhibitory Activity

Infections caused by the bacterium Staphylococcus aureus continue to pose threats to human health and put a financial burden on the healthcare system. The overuse of antibiotics has contributed to mutations leading to the emergence of methicillin-resistant S. aureus, and there is a critical need for the discovery and development of new antibiotics to evade drug-resistant bacteria. Medicinal plants have shown promise as sources of new small-molecule therapeutics with potential uses against pathogenic infections. The principal Rhode Island secondary metabolite (PRISM) library is a botanical extract library generated from specimens in the URI Youngken Medicinal Garden by upper-division undergraduate students. PRISM extracts were screened for activity against strains of methicillin-susceptible S. aureus (MSSA). An extract generated from the tulip tree (Liriodendron tulipifera) demonstrated growth inhibition against MSSA, and a bioassay-guided approach identified a sesquiterpene lactone, laurenobiolide, as the active constituent. Intriguingly, its isomers, tulipinolide and epi-tulipinolide, lacked potent activity against MSSA. Laurenobiolide also proved to be more potent against MSSA than the structurally similar sesquiterpene lactones, costunolide and dehydrocostus lactone. Laurenobiolide was the most abundant in the twig bark of the tulip tree, supporting the twig bark’s historical and cultural usage in poultices and teas

Predicting Preterm Birth Among Women Screened by North Carolina’s Pregnancy Medical Home Program

To determine which combination of risk factors from Community Care of North Carolina’s (CCNC) Pregnancy Medical Home (PMH) risk screening form was most predictive of preterm birth (PTB) by parity and race/ethnicity

Social correlates of distress following hematopoietic stem cell transplantation: Exploring the role of loneliness and cognitive processing

This study investigated whether loneliness and cognitive processing explain the influence of negative (social constraints) and positive (emotional support) relationship qualities on cancer survivors’ distress. Participants were 195 cancer survivors who had undergone hematopoietic stem cell transplantation. Path analysis supported the hypothesis that loneliness and cognitive processing would mediate the association between social constraints and distress. Only loneliness mediated the association between emotional support and distress—an indirect effect significant only when support came from family and friends rather than a partner. Findings suggest that addressing social constraints may enhance cancer survivors’ adjustment

Self-Efficacy Beliefs Mediate the Relationship between Subjective Cognitive Functioning and Physical and Mental Well-Being after Hematopoietic Stem Cell Transplant

Cognitive problems are commonly reported by hematopoietic stem cell transplant (HSCT) survivors, and are associated with poorer physical and mental well-being. It was hypothesized that adverse effects of subjective cognitive impairment occur because cognitive difficulties reduce survivors’ confidence that they can manage HSCT-related symptoms—that is, self-efficacy for symptom management

Experiences of venue based exercise interventions for people with stroke in the UK: a systematic review and thematic synthesis of qualitative research

Background The physical benefits of exercise following stroke are research evidenced and the UK stroke population is increasingly encouraged to engage with exercise interventions. A synthesis of qualitative research is required to further understand the perceived experience and psychosocial effect of exercise for people with stroke. Objectives To provide a systematic search and synthesis of evidence about the experiences and reported impact of participation in venue based exercise following stroke in the UK. Data sources Eligible studies were identified through a rigorous search of Medline, Cinahl, AMED, PsycINFO, SportDiscus, Proquest and ETHOS from January 2000 until December 2017. Study eligibility criteria Full text qualitative studies or service evaluations conducted in the UK which explored the reported experience of venue based exercise amongst people with stroke. Study synthesis and appraisal Included studies were evaluated through application of the Consolidated Criteria for Reporting Qualitative Research. Data synthesis using a thematic approach generated descriptive and analytical themes. Results Six research studies and one service evaluation met the inclusion criteria; methodological quality was variable. These studies highlighted that people with stroke gain confidence and renewed identity through exercise participation. Perceived improvements in physical function were reported and participants enjoyed stroke specific exercise programmes in de-medicalised venues. Limitations The studies only accessed people who had completed the exercise programmes; non-completers were not represented. Conclusion Venue based exercise programmes have a positive effect on perceived wellbeing following stroke. Further research into the reasons for discontinuation of exercise participation following stroke is required