Search Results Heading

MBRLSearchResults

mbrl.module.common.modules.added.book.to.shelf
Title added to your shelf!
View what I already have on My Shelf.
Oops! Something went wrong.
Oops! Something went wrong.
While trying to add the title to your shelf something went wrong :( Kindly try again later!
Are you sure you want to remove the book from the shelf?
Oops! Something went wrong.
Oops! Something went wrong.
While trying to remove the title from your shelf something went wrong :( Kindly try again later!
    Done
    Filters
    Reset
  • Discipline
      Discipline
      Clear All
      Discipline
  • Is Peer Reviewed
      Is Peer Reviewed
      Clear All
      Is Peer Reviewed
  • Item Type
      Item Type
      Clear All
      Item Type
  • Subject
      Subject
      Clear All
      Subject
  • Year
      Year
      Clear All
      From:
      -
      To:
  • More Filters
73 result(s) for "Lebel, Richard"
Sort by:
Potential of LiDAR and Hyperspectral Sensing for Overcoming Challenges in Current Maritime Ballast Tank Corrosion Inspection
Corrosion in maritime ballast tanks is a major driver of maintenance costs and operational risks for maritime assets. Inspections are hampered by complex geometries, hazardous conditions, and the limitations of conventional methods, particularly visual assessment, which struggles with subjectivity, accessibility, and early detection, especially under coatings. This paper critically examines these challenges and explores the potential of Light Detection and Ranging (LiDAR) and Hyperspectral Imaging (HSI) to form the basis of improved inspection approaches. We discuss LiDAR’s utility for accurate 3D mapping and providing a spatial framework and HSI’s potential for objective material identification and surface characterization based on spectral signatures along a wavelength range of 400-1000nm (visible and near infrared). Preliminary findings from laboratory tests are presented, demonstrating the basic feasibility of HSI for differentiating surface conditions (corrosion, coatings, bare metal) and relative coating thickness, alongside LiDAR’s capability for detailed geometric capture. Although these results do not represent a deployable system, they highlight how LiDAR and HSI could address key limitations of current practices and suggest promising directions for future research into integrated sensor-based corrosion assessment strategies.
Consistent gut bacterial and short-chain fatty acid signatures in hypoabsorptive bariatric surgeries correlate with metabolic benefits in rats
ObjectiveThe study aimed at comparing how changes in the gut microbiota are associated to the beneficial effects of the most clinically efficient hypoabsorptive bariatric procedures, namely Roux-en-Y gastric bypass (RYGB), biliopancreatic diversion with duodenal switch (BPD-DS) and single anastomosis duodeno-ileal bypass with sleeve gastrectomy (SADI-S).MethodsDiet-induced obese (DIO) male Wistar rats were divided into seven groups. In addition to the groups subjected to RYGB, BPD-DS and SADI-S, the following four control groups were included: SHAM-operated rats fed a high-fat diet (SHAM HF), SHAM fed a low-fat diet (SHAM LF), SHAM HF-pair-weighed to BPD-DS (SHAM HF-PW) and sleeve-gastrectomy (SG) rats. Body weight, food intake, glucose tolerance, insulin sensitivity/resistance, and L-cell secretion were assessed. The gut microbiota (16 S ribosomal RNA gene sequencing) as well as the fecal and cæcal contents of short-chain fatty acids (SCFAs) were also analyzed prior to, and after the surgeries.ResultsThe present study demonstrates the beneficial effect of RYGB, BPD-DS and SADI-S on fat mass gain and glucose metabolism in DIO rats. These benefits were proportional to the effect of the surgeries on food digestibility (BPD-DS > SADI-S > RYGB). Notably, hypoabsorptive surgeries led to consonant microbial signatures characterized by decreased abundance of the Ruminococcaceae (Oscillospira and Ruminococcus), Oscillospiraceae (Oscillibacter) and Christensenellaceae, and increased abundance of the Clostridiaceae (Clostridium), Sutterellaceae (Sutterella) and Enterobacteriaceae. The gut bacteria following hypoabsorptive surgeries were associated with higher fecal levels of propionate, butyrate, isobutyrate and isovalerate. Increases in the fecal SCFAs were in turn positively and strongly correlated with the levels of peptide tyrosine-tyrosine (PYY) and with the beneficial effects of the surgery.ConclusionThe present study emphasizes the consistency with which the three major hypoabsorptive bariatric procedures RYGB, BPD-DS and SADI-S create a gut microbial environment capable of producing a SCFA profile favorable to the secretion of PYY and to beneficial metabolic effects.
Molecular remodeling of adipose tissue is associated with metabolic recovery after weight loss surgery
Background Bariatric surgery is an effective therapy for individuals with severe obesity to achieve sustainable weight loss and to reduce comorbidities. Examining the molecular signature of subcutaneous adipose tissue (SAT) following different types of bariatric surgery may help in gaining further insight into their distinct metabolic impact. Results Subjects undergoing biliopancreatic diversion with duodenal switch (BPD-DS) showed a significantly higher percentage of total weight loss than those undergoing gastric bypass or sleeve gastrectomy (RYGB + SG) (41.7 ± 4.6 vs 28.2 ± 6.8%; p = 0.00005). Individuals losing more weight were also significantly more prone to achieve both type 2 diabetes and dyslipidemia remission (OR = 0.75; 95%CI = 0.51–0.91; p = 0.03). Whole transcriptome and methylome profiling showed that bariatric surgery induced a profound molecular remodeling of SAT at 12 months postoperative, mainly through gene down-regulation and hypermethylation. The extent of changes observed was greater following BPD-DS, with 61.1% and 49.8% of up- and down-regulated genes, as well as 85.7% and 70.4% of hyper- and hypomethylated genes being exclusive to this procedure, and mostly associated with a marked decrease of immune and inflammatory responses. Weight loss was strongly associated with genes being simultaneously differentially expressed and methylated in BPD-DS, with the strongest association being observed for GPD1L (r 2  = 0.83; p = 1.4 × 10 –6 ). Conclusions Present findings point to the greater SAT molecular remodeling following BPD-DS as potentially linked with higher metabolic remission rates. These results will contribute to a better understanding of the metabolic pathways involved in the response to bariatric surgery and will eventually lead to the development of gene targets for the treatment of obesity. Trial registration ClinicalTrials.gov NCT02390973.
Patient Outcomes After Treatment by Athletic Therapy Students
Patient-reported outcome measures (PROMs) should be used in athletic training and athletic therapy but are rarely incorporated in internships. Student-run clinics are common in other health professions and provide effective treatment and valuable learning environments. To our knowledge, no one has evaluated rehabilitation outcomes in patients treated by athletic therapy students (ATSs). To measure the improvement in function in injured patients seeking treatment at an ATS clinic. Cohort study. An ATS clinic. A total of 59 patients (32 women, age = 33.9 ± 14.7 years; 27 men, age = 38 ± 14.4 years) from the community with a variety of low back, lower extremity, and upper extremity injuries participated. At baseline and 6-week follow-up, all patients completed 1 of 3 scales (depending on their injury location) to assess their injured level of function. Scales were the Oswestry Disability Index for low back injuries; Lower Extremity Functional Scale for lower extremity injuries; and Disabilities of the Arm, Shoulder and Hand for upper extremity injuries. On average, patients received 4.7 ± 1.8 treatments across 48.8 ± 16.1 days. They experienced an increase in function between baseline and follow-up assessments (18.8% ± 20.3%; P < .001, Cohen d = 1.06). Moreover, the amount of functional improvement was clinically meaningful, as it was greater than the minimal clinically important difference for each scale. The efficacy of treatments did not differ according to the internship experiences of the ATSs. Function improved in patients after treatment delivered by an ATS. Patient-reported outcome measures were useful for the students in monitoring patient improvement, but more research is needed regarding effective treatments for patients with chronic pain. Our results suggested that ATS clinics provide effective treatments for patients, service to the community, and a learning opportunity for students.
White Matter Structural Connectivity Is Not Correlated to Cortical Resting-State Functional Connectivity over the Healthy Adult Lifespan
Structural connectivity (SC) of white matter (WM) and functional connectivity (FC) of cortical regions undergo changes in normal aging. As WM tracts form the underlying anatomical architecture that connects regions within resting state networks (RSNs), it is intuitive to expect that SC and FC changes with age are correlated. Studies that investigated the relationship between SC and FC in normal aging are rare, and have mainly compared between groups of elderly and younger subjects. The objectives of this work were to investigate linear SC and FC changes across the healthy adult lifespan, and to define relationships between SC and FC measures within seven whole-brain large scale RSNs. Diffusion tensor imaging (DTI) and resting-state functional MRI (rs-fMRI) data were acquired from 177 healthy participants (male/female = 69/108; aged 18-87 years). Forty cortical regions across both hemispheres belonging to seven template-defined RSNs were considered. Mean diffusivity (MD), fractional anisotropy (FA), mean tract length, and number of streamlines derived from DTI data were used as SC measures, delineated using deterministic tractography, within each RSN. Pearson correlation coefficients of rs-fMRI-obtained BOLD signal time courses between cortical regions were used as FC measure. SC demonstrated significant age-related changes in all RSNs (decreased FA, mean tract length, number of streamlines; and increased MD), and significant FC decrease was observed in five out of seven networks. Among the networks that showed both significant age related changes in SC and FC, however, SC was not in general significantly correlated with FC, whether controlling for age or not. The lack of observed relationship between SC and FC suggests that measures derived from DTI data that are commonly used to infer the integrity of WM microstructure are not related to the corresponding changes in FC within RSNs. The possible temporal lag between SC and FC will need to be addressed in future longitudinal studies to better elucidate the links between SC and FC changes in normal aging.
Vascular and blood-brain barrier-related changes underlie stress responses and resilience in female mice and depression in human tissue
Prevalence, symptoms, and treatment of depression suggest that major depressive disorders (MDD) present sex differences. Social stress-induced neurovascular pathology is associated with depressive symptoms in male mice; however, this association is unclear in females. Here, we report that chronic social and subchronic variable stress promotes blood-brain barrier (BBB) alterations in mood-related brain regions of female mice. Targeted disruption of the BBB in the female prefrontal cortex (PFC) induces anxiety- and depression-like behaviours. By comparing the endothelium cell-specific transcriptomic profiling of the mouse male and female PFC, we identify several pathways and genes involved in maladaptive stress responses and resilience to stress. Furthermore, we confirm that the BBB in the PFC of stressed female mice is leaky. Then, we identify circulating vascular biomarkers of chronic stress, such as soluble E-selectin. Similar changes in circulating soluble E-selectin, BBB gene expression and morphology can be found in blood serum and postmortem brain samples from women diagnosed with MDD. Altogether, we propose that BBB dysfunction plays an important role in modulating stress responses in female mice and possibly MDD. The vascular, cellular and molecular changes underlying sex differences in mood disorders are unclear. Here, the authors show that blood-brain barrier dysfunction modulates anxiety- and depressive-like behaviors in female mice and endothelium-specific changes associated with maladaptive responses compared to resilience to stress.
Hypoabsorptive surgeries cause limb-dependent changes in the gut endocannabinoidome and microbiome in association with beneficial metabolic effects
Objective To determine whether the metabolic benefits of hypoabsorptive surgeries are associated with changes in the gut endocannabinoidome (eCBome) and microbiome. Methods Biliopancreatic diversion with duodenal switch (BPD-DS) and single anastomosis duodeno-ileal bypass with sleeve gastrectomy (SADI-S) were performed in diet-induced obese (DIO) male Wistar rats. Control groups fed a high-fat diet (HF) included sham-operated (SHAM HF) and SHAM HF-pair-weighed to BPD-DS (SHAM HF-PW). Body weight, fat mass gain, fecal energy loss, HOMA-IR, and gut-secreted hormone levels were measured. The levels of eCBome lipid mediators and prostaglandins were quantified in different intestinal segments by LC-MS/MS, while expression levels of genes encoding eCBome metabolic enzymes and receptors were determined by RT-qPCR. Metataxonomic (16S rRNA) analysis was performed on residual distal jejunum, proximal jejunum, and ileum contents. Results BPD-DS and SADI-S reduced fat gain and HOMA-IR, while increasing glucagon-like peptide-1 (GLP-1) and peptide tyrosine tyrosine (PYY) levels in HF-fed rats. Both surgeries induced potent limb-dependent alterations in eCBome mediators and in gut microbial ecology. In response to BPD-DS and SADI-S, changes in gut microbiota were significantly correlated with those of eCBome mediators. Principal component analyses revealed connections between PYY, N -oleoylethanolamine (OEA), N -linoleoylethanolamine (LEA), Clostridium , and Enterobacteriaceae_g_2 in the proximal and distal jejunum and in the ileum. Conclusions BPD-DS and SADI-S caused limb-dependent changes in the gut eCBome and microbiome. The present results indicate that these variables could significantly influence the beneficial metabolic outcome of hypoabsorptive bariatric surgeries.
Exploring the implementation and underlying mechanisms of centralized referral systems to access specialized health services in Quebec
Background In 2016, Quebec, a Canadian province, implemented a program to improve access to specialized health services ( Accès priorisé aux services spécialisés (APSS)), which includes single regional access points for processing requests to such services via primary care ( Centre de répartition des demandes de services (CRDS)). Family physicians fill out and submit requests for initial consultations with specialists using a standardized form with predefined prioritization levels according to listed reasons for consultations, which is then sent to the centralized referral system (the CRDS) where consultations with specialists are assigned. We 1) described the APSS-CRDS program in three Quebec regions using logic models; 2) compared similarities and differences in the components and processes of the APSS-CRDS models; and 3) explored contextual factors influencing the models’ similarities and differences. Methods We relied on a qualitative study to develop logic models of the implemented APSS-CRDS program in three regions. Semi-structured interviews with health administrators ( n  = 9) were conducted. The interviews were analysed using a framework analysis approach according to the APSS-CRDS’s components included in the initially designed program, Mitchell and Lewis (2003)’s logic model framework, and Chaudoir and colleagues (2013)’s framework on contextual factors’ influence on an innovation’s implementation. Results Findings show the APSS-CRDS program’s regional variability in the implementation of its components, including its structure (centralized/decentralized), human resources involved in implementation and operation, processes to obtain specialists’ availability and assess/relay requests, as well as monitoring methods. Variability may be explained by contextual factors’ influence, like ministerial and medical associations’ involvement, collaborations, the context’s implementation readiness, physician practice characteristics, and the program’s adaptability. Interpretation Findings are useful to inform decision-makers on the design of programs like the APSS-CRDS, which aim to improve access to specialists, the essential components for the design of these types of interventions, and how contextual factors may influence program implementation. Variability in program design is important to consider as it may influence anticipated effects, a next step for the research team. Results may also inform stakeholders should they wish to implement similar programs to increase access to specialized health services via primary care.
Determination of a pharmacokinetic model for 11C-acetate in brown adipose tissue
Background[11C]-acetate positron emission tomography is used to assess oxidative metabolism in various tissues including the heart, tumor, and brown adipose tissue. For brown adipose tissue, a monoexponential decay model is commonly employed. However, no systematic assessment of kinetic models has been performed to validate this model or others.The monoexponential decay model and various compartmental models were applied to data obtained before and during brown adipose tissue activation by cold exposure in healthy men. Quality of fit was assessed visually and by analysis of residuals, including the Akaike information criterion. Stability and accuracy of compartmental models were further assessed through simulations, along with sensitivity and identifiability of kinetic parameters.ResultsDifferences were noted in the arterial input function between the warm and cold conditions. These differences are not taken into account by the monoexponential decay model. They are accounted for by compartmental models, but most models proved too complex to be stable. Two and three-tissue models with no more than four distinct kinetic parameters, including blood volume fraction, provided the best compromise between fit quality and stability/accuracy.ConclusionFor healthy men, a three-tissue model with four kinetic parameters, similar to a heart [11C]-palmitate model seems the most appropriate based on model stability and its ability to describe the main [11C]-acetate pathways in BAT cells. Further studies are required to validate this model in women and people with metabolic disorders.