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1.
Nat Commun ; 15(1): 3886, 2024 May 08.
Article de Anglais | MEDLINE | ID: mdl-38719856

RÉSUMÉ

Machine learning provides a data-driven approach for creating a digital twin of a system - a digital model used to predict the system behavior. Having an accurate digital twin can drive many applications, such as controlling autonomous systems. Often, the size, weight, and power consumption of the digital twin or related controller must be minimized, ideally realized on embedded computing hardware that can operate without a cloud-computing connection. Here, we show that a nonlinear controller based on next-generation reservoir computing can tackle a difficult control problem: controlling a chaotic system to an arbitrary time-dependent state. The model is accurate, yet it is small enough to be evaluated on a field-programmable gate array typically found in embedded devices. Furthermore, the model only requires 25.0 ± 7.0 nJ per evaluation, well below other algorithms, even without systematic power optimization. Our work represents the first step in deploying efficient machine learning algorithms to the computing "edge."

2.
Chaos ; 34(2)2024 Feb 01.
Article de Anglais | MEDLINE | ID: mdl-38305050

RÉSUMÉ

In this work, we combine nonlinear system control techniques with next-generation reservoir computing, a best-in-class machine learning approach for predicting the behavior of dynamical systems. We demonstrate the performance of the controller in a series of control tasks for the chaotic Hénon map, including controlling the system between unstable fixed points, stabilizing the system to higher order periodic orbits, and to an arbitrary desired state. We show that our controller succeeds in these tasks, requires only ten data points for training, can control the system to a desired trajectory in a single iteration, and is robust to noise and modeling error.

3.
J Am Med Dir Assoc ; 22(10): 1998-2002, 2021 10.
Article de Anglais | MEDLINE | ID: mdl-34418376

RÉSUMÉ

The rate of coronavirus disease 2019 (COVID-19) vaccination uptake by US nursing home staff remains low despite the increased risks of viral transmission and related morbidity and mortality in this setting. This study describes vaccine uptake activities including a COVID-19 vaccination condition of employment (COE) policy in one community nursing home. This case study summarizes the timeline of vaccination uptake activities, staff vaccination rates over time, and stakeholder perspectives around the implementation of a COVID-19 vaccination COE. Organizational data were used to calculate vaccination rates from January 1, 2021 until May 1, 2021 among all nursing home staff. Interviews were held with the executive leadership team, human resources leadership, and nursing home staff to understand the process of implementation. During a 4-month period, nursing home leaders provided 8 written handouts about COVID-19 to all staff, hosted 5 on-site vaccination clinics in partnership with area pharmacies, conducted 2 virtual presentations for staff in addition to individual outreach and internal communications. Fewer than one-half of the staff were vaccinated prior to the decision to pursue a vaccine COE on February 9, 2021. The decision to pursue a COVID-19 vaccination COE was supported by executive leadership and nursing home staff to protect the health and safety of each other and their residents. By May 1, 2021 a total of 221 of the 246 (89.8%) nursing home staff members received a COVID-19 vaccination. The facility reached 100% compliance with the vaccination COE policy with 18 people who chose to resign and 7 people who were exempt or on a leave of absence. In combination with frequent, personalized outreach, a COVID-19 vaccination COE resulted in high staff vaccination rates and minimal staff turnover. This case study provides a detailed summary of vaccination uptake activities within an organizational context to inform efforts at other healthcare facilities.


Sujet(s)
COVID-19 , Vaccins contre la COVID-19 , Emploi , Humains , Maisons de repos , SARS-CoV-2 , Vaccination
5.
J Clin Endocrinol Metab ; 104(9): 3661-3669, 2019 09 01.
Article de Anglais | MEDLINE | ID: mdl-31127818

RÉSUMÉ

BACKGROUND AND AIMS: Enteroendocrine L cells release satiety inducing hormones in response to stimulation by luminal macronutrients. We sought to profile the differential effect of macronutrient type and site of release on circulating concentrations of the L cell-derived enteroendocrine hormone peptide tyrosine tyrosine (amino acids 1 to 36) (PYY). MATERIALS AND METHODS: Eight healthy volunteers were recruited to a randomized, double-blinded, six-way crossover study. At each visit, the participants consumed a 500-kcal drink containing carbohydrate, protein, or fat in either gastric or small intestinal release formulations. Plasma PYY concentrations and hunger ratings were assessed for 3 hours after consumption of the test drink. The food intake was recorded thereafter at an ad libitum lunch. RESULTS: Microcapsular formulations targeting the distal small intestinal delivery of fat, but not carbohydrate or protein, markedly enhance PYY release relative to macronutrient delivery in gastric release formulations. Food intake at an ad libitum meal was lowest after consumption of the formulation releasing fat at the distal small intestine. CONCLUSION: Targeting of fat to the distal small intestine in delayed release microcapsules enhanced PYY release and was associated with reductions in food intake.


Sujet(s)
Ration calorique , Cellules entéroendocrines/métabolisme , Faim/physiologie , Intestin grêle/métabolisme , Nutriments/administration et posologie , Peptide YY/sang , Satiété/physiologie , Adolescent , Adulte , Études croisées , Comportement alimentaire , Femelle , Études de suivi , Volontaires sains , Humains , Faim/effets des médicaments et des substances chimiques , Mâle , Repas , Adulte d'âge moyen , Projets pilotes , Période post-prandiale/effets des médicaments et des substances chimiques , Période post-prandiale/physiologie , Pronostic , Satiété/effets des médicaments et des substances chimiques , Jeune adulte
6.
Sci Rep ; 7(1): 13523, 2017 10 19.
Article de Anglais | MEDLINE | ID: mdl-29051554

RÉSUMÉ

ABSTACT: The gut hormone glucagon-like peptide (GLP)-1 and its analogues represent a new generation of anti-diabetic drugs, which have also demonstrated propensity to modulate host lipid metabolism. Despite this, drugs of this nature are currently limited to intramuscular administration routes due to intestinal degradation. The aim of this study was to design a recombinant microbial delivery vector for a GLP-1 analogue and assess the efficacy of the therapeutic in improving host glucose, lipid and cholesterol metabolism in diet induced obese rodents. Diet-induced obese animals received either Lactobacillus paracasei NFBC 338 transformed to express a long-acting analogue of GLP-1 or the isogenic control microbe which solely harbored the pNZ44 plasmid. Short-term GLP-1 microbe intervention in rats reduced serum low-density lipoprotein cholesterol, triglycerides and triglyceride-rich lipoprotein cholesterol substantially. Conversely, extended GLP-1 microbe intervention improved glucose-dependent insulin secretion, glucose metabolism and cholesterol metabolism, compared to the high-fat control group. Interestingly, the microbe significantly attenuated the adiposity associated with the model and altered the serum lipidome, independently of GLP-1 secretion. These data indicate that recombinant incretin-secreting microbes may offer a novel and safe means of managing cholesterol metabolism and diet induced dyslipidaemia, as well as insulin sensitivity in metabolic dysfunction.


Sujet(s)
Alimentation riche en graisse , Glucagon-like peptide 1/génétique , Lactobacillus/métabolisme , Obésité/thérapie , Animaux , Cholestérol LDL/sang , Modèles animaux de maladie humaine , Glucose/métabolisme , Hyperglycémie provoquée , Insuline/métabolisme , Cellules à insuline/métabolisme , Cellules à insuline/microbiologie , Lactobacillus/génétique , Métabolome , Souris , Souris de lignée C57BL , Obésité/étiologie , Plasmides/génétique , Plasmides/métabolisme , Rats , Rat Long-Evans , Triglycéride/sang
7.
J Diet Suppl ; 14(4): 433-445, 2017 Jul 04.
Article de Anglais | MEDLINE | ID: mdl-28121472

RÉSUMÉ

Creatine monohydrate represents one of the largest sports supplement markets. Enhancing creatine (CRE) stability in aqueous solutions, such as with microencapsulation, represents innovation potential. Ten physically active male volunteers were randomly assigned in a double-blind design to either placebo (PLA) (3-g maltodextrin; n = 5) or microencapsulated CRE (3-g creatine monohydrate; n = 5) conditions. Experimental conditions involved ingestion of the samples in a 70-mL ready-to-drink format. CRE was delivered in a novel microencapsulation matrix material consisting entirely of hydrolyzed milk protein. Three hours after ingestion, plasma creatine concentrations were unchanged during PLA, and averaged ∼45 µM. During CRE, plasma creatine concentration peaked after 30 min at 101.6 ± 14.9 µM (p < 0.05), representing a 2.3-fold increase over PLA. Thereafter, plasma creatine concentration gradually trended downwards but remained significantly elevated (∼50% above resting levels) 3 hr after ingestion. These results demonstrate that the microencapsulated form of creatine monohydrate reported herein remains bioavailable when delivered in aqueous conditions, and has potential utility in ready-to-drink formulations for creatine supplementation.


Sujet(s)
Créatine/pharmacocinétique , Diosgénine/pharmacocinétique , Phytostérols/pharmacocinétique , Adulte , Biodisponibilité , Créatine/administration et posologie , Créatine/sang , Diosgénine/administration et posologie , Méthode en double aveugle , Préparation de médicament , Stabilité de médicament , Consommation alimentaire , Volontaires sains , Humains , Mâle , Protéines de lait , Phytostérols/administration et posologie , Hydrolysats de protéines , Répartition aléatoire , Solutions
8.
Nutrients ; 7(2): 1217-44, 2015 Feb 12.
Article de Anglais | MEDLINE | ID: mdl-25685987

RÉSUMÉ

Human milk is recognised as the best form of nutrition for infants. However; in instances where breast-feeding is not possible, unsuitable or inadequate, infant milk formulae are used as breast milk substitutes. These formulae are designed to provide infants with optimum nutrition for normal growth and development and are available in either powdered or liquid forms. Powdered infant formula is widely used for convenience and economic reasons. However; current manufacturing processes are not capable of producing a sterile powdered infant formula. Due to their immature immune systems and permeable gastro-intestinal tracts, infants can be more susceptible to infection via foodborne pathogenic bacteria than other age-groups. Consumption of powdered infant formula contaminated by pathogenic microbes can be a cause of serious illness. In this review paper, we discuss the current manufacturing practices present in the infant formula industry, the pathogens of greatest concern, Cronobacter and Salmonella and methods of improving the intrinsic safety of powdered infant formula via the addition of antimicrobials such as: bioactive peptides; organic acids; probiotics and prebiotics.


Sujet(s)
Anti-infectieux/administration et posologie , Contamination des aliments/prévention et contrôle , Industrie alimentaire/méthodes , Aliment du nourrisson au cours de la première année/microbiologie , Préparation pour nourrissons , Femelle , Industrie alimentaire/tendances , Humains , Nourrisson , Nouveau-né , Mâle , Peptides/administration et posologie , Prébiotiques/microbiologie , Probiotiques/administration et posologie
9.
PLoS One ; 9(2): e88599, 2014.
Article de Anglais | MEDLINE | ID: mdl-24586349

RÉSUMÉ

Forty eight individual pigs (8.7±0.26 kg) weaned at 28±1 d of age were used in a 22-d study to evaluate the effect of oral administration of a Bacillus pumilus spore suspension on growth performance and health indicators. Treatments (n = 16) were: (1) non-medicated diet; (2) medicated diet with apramycin (200 mg/kg) and pharmacological levels of zinc oxide (2,500 mg zinc/kg) and (3) B. pumilus diet (non-medicated diet + 10(10) spores/day B. pumilus). Final body weight and average daily gain tended to be lower (P = 0.07) and feed conversion ratio was worsened (P<0.05) for the medicated treatment compared to the B. pumilus treatment. Ileal E. coli counts were lower for the B. pumilus and medicated treatments compared to the non-medicated treatment (P<0.05), perhaps as a result of increased ileal propionic acid concentrations (P<0.001). However, the medicated treatment reduced fecal (P<0.001) and cecal (P<0.05) Lactobacillus counts and tended to reduce the total cecal short chain fatty acid (SCFA) concentration (P = 0.10). Liver weights were lighter and concentrations of liver enzymes higher (P<0.05) in pigs on the medicated treatment compared to those on the non-medicated or B. pumilus treatments. Pigs on the B. pumilus treatment had lower overall lymphocyte and higher granulocyte percentages (P<0.001) and higher numbers of jejunal goblet cells (P<0.01) than pigs on either of the other two treatments or the non-medicated treatment, respectively. However, histopathological examination of the small intestine, kidneys and liver revealed no abnormalities. Overall, the B. pumilus treatment decreased ileal E. coli counts in a manner similar to the medicated treatment but without the adverse effects on growth performance, Lactobacillus counts, cecal SCFA concentration and possible liver toxicity experienced with the medicated treatment.


Sujet(s)
Aliment pour animaux , Bacillus , Biologie marine , Probiotiques , Sevrage , Animaux , Escherichia coli/isolement et purification , Femelle , Concentration en ions d'hydrogène , Intestins/microbiologie , Lactobacillus/isolement et purification , Mâle , Taille d'organe , Suidae
10.
Food Res Int ; 64: 567-576, 2014 Oct.
Article de Anglais | MEDLINE | ID: mdl-30011690

RÉSUMÉ

The perceived health benefit of probiotics has led to a rapid expansion of their use in various health-based products. The beneficial effect of these probiotic cells is largely dependent on their ability to reach their appropriate site of action, usually the distal gut, in a viable condition and in sufficient numbers. In an attempt to establish a microbiota in formula-fed infants resembling that of breast-fed ones, infant formula manufacturers are increasingly incorporating probiotics into their products. The administration of probiotic cells via oral administration is associated with a large decrease in the number of viable cells due to the high acid and bile salt concentrations present in the stomach. Powdered infant formulae are also expected to have long term stability particularly in comparison to products normally associated with probiotics, which can adversely affect the viability of probiotic cells. Finally, the processing techniques used to generate infant formula can cause a dramatic loss in the number of viable cells present in the product by the time it is consumed. Microencapsulation technology is emerging as an effective way to protect cells during food processing and also allows targeted delivery of the cells to appropriate sites in the gastro-intestinal tract improving the efficacy of the final product and lowering the economic cost incurred by producers due to logistic and stability issues. In this review, the current situation of probiotics in infant formula, and the encapsulation techniques being developed using milk and pea proteins as encapsulating materials to improve their viability are discussed.

11.
PLoS One ; 6(4): e18740, 2011 Apr 20.
Article de Anglais | MEDLINE | ID: mdl-21533100

RÉSUMÉ

Genetic diversity and genomic rearrangements are a driving force in bacterial evolution and niche adaptation. We sequenced and annotated the genome of Lactobacillus johnsonii DPC6026, a strain isolated from the porcine intestinal tract. Although the genome of DPC6026 is similar in size (1.97 mbp) and GC content (34.8%) to the sequenced human isolate L. johnsonii NCC 533, a large symmetrical inversion of approximately 750 kb differentiated the two strains. Comparative analysis among 12 other strains of L. johnsonii including 8 porcine, 3 human and 1 poultry isolate indicated that the genome architecture found in DPC6026 is more common within the species than that of NCC 533. Furthermore a number of unique features were annotated in DPC6026, some of which are likely to have been acquired by horizontal gene transfer (HGT) and contribute to protection against phage infection. A putative type III restriction-modification system was identified, as were novel Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) elements. Interestingly, these particular elements are not widely distributed among L. johnsonii strains. Taken together these data suggest intra-species genomic rearrangements and significant genetic diversity within the L. johnsonii species and indicate towards a host-specific divergence of L. johnsonii strains with respect to genome inversion and phage exposure.


Sujet(s)
Bactériophages/physiologie , Inversion chromosomique , Lactobacillus/physiologie , Éléments transposables d'ADN , Lactobacillus/classification , Lactobacillus/génétique , Phylogenèse
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