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1.
Heliyon ; 10(4): e26144, 2024 Feb 29.
Article in English | MEDLINE | ID: mdl-38390105

ABSTRACT

Within various unstructured industrial environments, there is often the requirement to conduct remote engineering tasks, such as sampling the structure for analysis prior to decommissioning. Most existing tools are simply not dexterous enough to fulfil this task, and thus new technology is required. We describe here a simple, lightweight, and water-resistant collaborative dual-arm continuum robot system which can aid in this task. To improve the kinematic accuracy of the system, a class of flexible hinges have been combined with a conventional continuum robot configuration. The thickness and width of said flexible hinges can be adjusted to adapt to various tasks. Kinematic and stiffness models have further been developed, incorporating the influence of these flexible hinges. A set of experiments have been conducted to validate the proposed model and demonstrate the advantages of the platform. It was found that the kinematic accuracy of the continuum robot can be improved by a factor of around 10 with the aid of said hinges.

2.
J Frailty Aging ; 11(1): 74-82, 2022.
Article in English | MEDLINE | ID: mdl-35122094

ABSTRACT

BACKGROUND: Older adults with Type 2 diabetes (T2D) are more likely to be frail, which increases the risk for disability and mortality. OBJECTIVES: To determine the feasibility of a behavioral lifestyle intervention, enhanced with mobile health technology for self-monitoring of diet and activity, to improve frailty in overweight/obese older adults (≥65 years) diagnosed with T2D. DESIGN, SETTING, AND PARTICIPANTS: Single arm, 6-month study of a behavioral lifestyle intervention in 20 overweight/obese (BMI>25) older adults (≥ 65 years) with self-reported T2D diagnosis who owned a smartphone. A Fitbit tracker was provided to all participants for self-monitoring of diet and physical activity. Our primary outcome of feasibility was measured by session attendance, adherence to Fitbit usage to self-monitor diet and physical activity, and study retention. Secondary outcomes included the preliminary efficacy of the intervention on frailty, physical function, quality of life, and T2D-related outcomes. RESULTS: Eighteen participants completed the study. The mean age was 71.5 (SD ± 5.3) years, 56% were female, and half were Hispanic. At baseline, 13 (72%) were pre-frail, 4 (22%) were frail, and 1 (6%) were non-frail. At follow-up, frailty scores improved significantly from 1.61 ± 1.15 to 0.94 ± 0.94 (p=0.01) and bodyweight improved from 205.66 ± 45.52 lbs. to 198.33 ± 43.6 lbs. (p=<0.001). CONCLUSION: This study provides evidence for the feasibility of a behavioral lifestyle intervention in overweight/obese older adults with T2D and preliminary results support its potential efficacy in improving frailty score.


Subject(s)
Diabetes Mellitus, Type 2 , Frailty , Aged , Diabetes Mellitus, Type 2/therapy , Feasibility Studies , Female , Humans , Life Style , Obesity/therapy , Overweight/therapy , Quality of Life
3.
J Prev Alzheimers Dis ; 4(4): 247-254, 2017.
Article in English | MEDLINE | ID: mdl-29181490

ABSTRACT

Several ongoing clinical development programs are investigating potential disease-modifying treatments for Alzheimer's disease (AD), including lanabecestat (AZD3293/LY3314814). Lanabecestat is a brain-permeable oral inhibitor of human beta-site amyloid (Aß) precursor protein-cleaving enzyme 1 (BACE1) that reduces Aß production. As a potent BACE1 inhibitor, lanabecestat significantly reduced soluble Aß species and soluble amyloid precursor proteins (sAPPß) in mouse, guinea pig, and dog in a time- and dose-dependent manner. Significant reductions in plasma and cerebrospinal fluid (CSF) Aß1-40 and Aß1-42 were observed in Phase 1 studies of healthy subjects and AD patients treated with lanabecestat. Three lanabecestat trials are ongoing and intended to support registration in Early AD: (1) Phase 2/3 study in patients with mild cognitive impairment (MCI) due to AD and mild AD dementia (AMARANTH, NCT02245737); (2) Delayed-start extension study (AMARANTH-EXTENSION, NCT02972658) for patients who have completed treatment in the AMARANTH Study; and (3) Phase 3 study in mild AD dementia (DAYBREAK-ALZ, NCT02783573). This review will discuss the development of lanabecestat, results from the completed nonclinical and clinical studies, as well as describe the ongoing Phase 3 clinical trials.


Subject(s)
Amyloid Precursor Protein Secretases/antagonists & inhibitors , Enzyme Inhibitors/pharmacology , Imidazoles/pharmacology , Spiro Compounds/pharmacology , Alzheimer Disease/blood , Alzheimer Disease/cerebrospinal fluid , Alzheimer Disease/drug therapy , Amyloid beta-Protein Precursor/metabolism , Animals , Clinical Trials as Topic , Cognitive Dysfunction/blood , Cognitive Dysfunction/cerebrospinal fluid , Cognitive Dysfunction/drug therapy , Enzyme Inhibitors/pharmacokinetics , Enzyme Inhibitors/therapeutic use , Humans , Imidazoles/pharmacokinetics , Imidazoles/therapeutic use , Spiro Compounds/pharmacokinetics , Spiro Compounds/therapeutic use
4.
AIDS Behav ; 19(8): 1478-90, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25863467

ABSTRACT

African Americans face disproportionate sexually transmitted infection including HIV (STI/HIV), with those passing through a correctional facility at heightened risk. There is a need to identify modifiable STI/HIV risk factors among incarcerated African Americans. Project DISRUPT is a cohort study of incarcerated African American men recruited from September 2011 through January 2014 from prisons in North Carolina who were in committed partnerships with women at prison entry (N = 207). During the baseline (in-prison) study visit, participants responded to a risk behavior survey and provided a urine specimen, which was tested for STIs. Substantial proportions reported multiple partnerships (42 %), concurrent partnerships (33 %), and buying sex (11 %) in the 6 months before incarceration, and 9 % tested positive for an STI at baseline (chlamydia: 5.3 %, gonorrhea: 0.5 %, trichomoniasis: 4.9 %). Poverty and depression appeared to be strongly associated with sexual risk behaviors. Substance use was linked to prevalent STI, with binge drinking the strongest independent risk factor (adjusted odds ratio: 3.79, 95 % CI 1.19-12.04). There is a continued need for improved prison-based STI testing, treatment, and prevention education as well as mental health and substance use diagnosis.


Subject(s)
Black or African American/psychology , HIV Infections/epidemiology , Mood Disorders/psychology , Poverty , Prisoners , Sexually Transmitted Diseases/epidemiology , Substance-Related Disorders/psychology , Adult , Cross-Sectional Studies , HIV Infections/psychology , Humans , Male , Middle Aged , North Carolina/epidemiology , Prevalence , Prisoners/statistics & numerical data , Prisons , Risk Factors , Risk-Taking , Sexual Behavior/statistics & numerical data , Sexual Partners , Sexually Transmitted Diseases/psychology , Unsafe Sex/statistics & numerical data
5.
Radiat Prot Dosimetry ; 164(3): 228-38, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25342608

ABSTRACT

Here, the characterisation of the high-energy neutron field at TRIUMF (The Tri Universities Meson Facility, Vancouver, British Columbia) with Monte Carlo simulation software is described. The package used is MCNPX version 2.6.0, with the neutron fluence rate determined at three locations within the TRIUMF Thermal Neutron Facility (TNF), including the exit of the neutron channel where users of the facility can test devices that may be susceptible to the effects of this form of radiation. The facility is often used to roughly emulate the field likely to be encountered at high altitudes due to radiation of galactic origin and thus the simulated information is compared with the energy spectrum calculated to be due to neutron radiation of cosmic origin at typical aircraft altitudes. The calculated values were also compared with neutron flux measurements that were estimated using the activation of various foils by the staff of the facility, showing agreement within an order of magnitude.


Subject(s)
Computer Simulation , Monte Carlo Method , Neutrons , Radiation Monitoring/instrumentation , Radiation Protection/instrumentation , Software , Aircraft , Altitude , Cosmic Radiation , Humans , Radiation Dosage
6.
Appl Radiat Isot ; 70(7): 1145-9, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22221462

ABSTRACT

A portable neutron spectrometry and dosimetry measurement device is in the process of development, which will be capable of accurate characterisation of neutron fields. The instrument is an amalgamation of two well-known techniques the Bonner-sphere and the surface barrier detector. Recent developments in semiconductor materials have allowed the growth of large-area thin-film based semiconductors upon high density polyethylene substrates, on which this detector is formed. Herein we discuss three plausible detection devices and test their results.

7.
Appl Radiat Isot ; 70(7): 1370-2, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22112596

ABSTRACT

The viability of various materials and blanket designs for use in nuclear fusion reactors can be tested using computer simulations and as parts of the test blanket modules within the International Thermonuclear Experimental Reactor (ITER) facility. The work presented here focuses on blanket model simulations using the Monte Carlo simulation package MCNPX (Computational Physics Division Los Alamos National Laboratory, 2010) and FISPACT (Forrest, 2007) to evaluate the tritium breeding capability of a number of solid and liquid breeding materials. The liquid/molten salt breeders are found to have the higher tritium breeding ratio (TBR) and are to be considered for further analysis of the self sufficiency timing.

8.
Appl Radiat Isot ; 70(7): 1288-90, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22189372

ABSTRACT

A Monte Carlo simulation package, MCNPX version 2.6.0, has been used to evaluate the effect on the response of a spherical neutron detector utilising various numbers of point detectors on the surface of a spherical polyethylene structure, which forms an instrument specifically designed for low radiation environments.

9.
Radiat Prot Dosimetry ; 144(1-4): 249-52, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21186214

ABSTRACT

Solid state-based surface barrier detectors (SBDs) have been employed in neutron radiation dosimetry for over half a century, each combination of detector featuring positives and pitfalls. Here the implications of constructing a portable neutron spectrometer device, based upon moderating high-density polyethylene substrates and utilising different types of large-area solid state SBDs, are discussed.


Subject(s)
Polyethylene/chemistry , Radiometry/instrumentation , Algorithms , Equipment Design , Hydrogen/chemistry , Materials Testing , Neutrons , Oxygen/chemistry , Polyethylene/analysis , Radiation Dosage , Radiometry/methods , Spectrophotometry/methods , Surface Properties , Temperature , Time Factors
10.
Radiat Prot Dosimetry ; 144(1-4): 182-6, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21186216

ABSTRACT

A Monte Carlo-based simulation of the transport of a series of monoenergetic neutron sources through first a rectangular block of 0.93 g cm(-3) density polyethylene and secondly through a sphere made of the same substance is presented here. In both instances, the neutron fields are monitored at closely spread intervals through the moderator mass, producing a lot of data in the process. To reduce the amount of data presented, a figure of merit is created by estimating the cross section for each discrete neutron energy and by applying this to the number of neutrons present of each energy giving an arbitrary response figure. This work was undertaken in order to aid the design and development of a novel neutron spectrometer.


Subject(s)
Polyethylene/analysis , Radiation Monitoring/instrumentation , Radiation Protection/instrumentation , Radiometry/instrumentation , Spectrophotometry/instrumentation , Alpha Particles , Beta Particles , Computer Simulation , Equipment Design , Humans , Materials Testing , Monte Carlo Method , Neutrons , Probability , Radiation Monitoring/methods , Radiation Protection/methods , Radiometry/methods , Spectrophotometry/methods
11.
Rev Sci Instrum ; 79(2 Pt 1): 023301, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18315287

ABSTRACT

The construction and testing of a portable energy-sensitive neutron instrument are described. This instrument has been designed and constructed for the primary purpose of characterizing cosmic-ray neutron fields in the upper atmosphere and in cosmic reference field facilities. The instrument comprises a helium-3 proportional counter surrounded by 15 mm of lead and 140 mm of polyethylene creating a spherical structure with a diameter of 34 cm. The instrument also incorporates 12 boron-coated diodes, six on the outside of the polyethylene layer with six placed within the structure. The dimensions, materials, and arrangement of these in the instrument have previously been optimized with the MCNPX Monte Carlo simulation software to provide a compromise between the requirements of portability and spectral response. Testing took place at several locations and experimental data from the instrument's operation at the high-altitude Jungfraujoch laboratory in the Swiss alps are presented.

12.
Radiat Prot Dosimetry ; 123(1): 3-14, 2007.
Article in English | MEDLINE | ID: mdl-16829509

ABSTRACT

The design of a portable three-band cosmic-ray neutron detector is reported in this article. This instrument has been designed to characterise cosmic ray neutron fields in the upper atmosphere and in cosmic reference field facilities. The design utilises a spherical moderator with a layer of spallation material covering a central (3)He proportional counter. The instrument incorporates twelve lithium-coated diodes, six on the outside of the polyethylene layer and six placed within the structure. The dimensions, materials and arrangement of these in the instrument have been optimised with MCNPX to provide a compromise between the requirements of portability and spectral response.


Subject(s)
Cosmic Radiation , Neutrons , Radiation Monitoring/instrumentation , Lithium/chemistry , Monte Carlo Method , Signal Processing, Computer-Assisted , Silicon/chemistry , Spectrum Analysis
13.
Respir Med ; 100(2): 300-6, 2006 Feb.
Article in English | MEDLINE | ID: mdl-16002272

ABSTRACT

There is increasing interest in ethane (C(2)H(6)) in exhaled breath as a non-invasive marker of oxidative stress (OS) and thereby a potential indicator of disease. However, the lack of real-time measurement techniques has limited progress in the field. Here we report on a novel Tunable Diode Laser Spectrometer (TDLS) applied to the analysis of exhaled ethane in patients with lung cancer. The patient group (n=52) comprised randomly selected patients presenting at a respiratory clinic. Of these, a sub-group (n=12) was subsequently diagnosed with lung cancer. An age-matched group (n=12) corresponding to the lung cancer group was taken from a larger control group of healthy adults (n=58). The concentration of ethane in a single exhaled breath sample collected from all subjects was later measured using the TDLS. This technique is capable of real-time analysis of samples with accuracy 0.1 parts per billion (ppb), over 10 times less than typical ambient levels in the northern hemisphere. After correcting for ambient background, ethane in the control group (26% smokers) ranged from 0 to 10.54 ppb (median of 1.9 ppb) while ethane in the lung cancer patients (42% smokers) ranged from 0 to 7.6 ppb (median of 0.7 ppb). Ethane among the non-lung cancer patients presenting for investigation of respiratory disease ranged from 0 to 25 ppb (median 1.45 ppb). We conclude that, while the TDLS proved effective for accurate and rapid sample analysis, there was no significant difference in exhaled ethane among any of the subject groups. Comments are made on the suitability of the technique for monitoring applications.


Subject(s)
Ethane/analysis , Lasers , Lung Neoplasms/diagnosis , Aged , Breath Tests/methods , Case-Control Studies , Humans , Prospective Studies , Random Allocation , Sensitivity and Specificity , Spectrum Analysis/standards
14.
Nature ; 432(7019): 878-81, 2004 Dec 16.
Article in English | MEDLINE | ID: mdl-15602555

ABSTRACT

The Earth's radiation belts--also known as the Van Allen belts--contain high-energy electrons trapped on magnetic field lines. The centre of the outer belt is usually 20,000-25,000 km from Earth. The region between the belts is normally devoid of particles, and is accordingly favoured as a location for spacecraft operation because of the benign environment. Here we report that the outer Van Allen belt was compressed dramatically by a solar storm known as the 'Hallowe'en storm' of 2003. From 1 to 10 November, the outer belt had its centre only approximately 10,000 km from Earth's equatorial surface, and the plasmasphere was similarly displaced inwards. The region between the belts became the location of high particle radiation intensity. This remarkable deformation of the entire magnetosphere implies surprisingly powerful acceleration and loss processes deep within the magnetosphere.

15.
Dtsch Med Wochenschr ; 129(48): 2586-9, 2004 Nov 26.
Article in German | MEDLINE | ID: mdl-15558406

ABSTRACT

BACKGROUND AND OBJECTIVE: In addition to basic research and development of new therapeutic strategies, the education of health care professionals who manage sepsis patients is an important step to decrease the high mortality of severe sepsis. Patient simulators are increasingly used for teaching in anaesthesia. A training program in sepsis management was developed, using a full-scale anaesthesia simulator including the setting of a modern intensive care unit, and its results were evaluated by means of a questionnaire. METHODS: The simulator is controlled from a separate room using a controlling computer provided with physiological models and pharmacokinetic as well as pharmacodynamic patterns of substances commonly used in anaesthesia and intensive care. An important element of the training program is the subsequent debriefing with different modules, according to the individual deficits and needs of the participants detected during simulation. RESULTS: From September 2002 to July 2004 82 physicians participated in the training program. 4 weeks after the training 52 % of the participants stated that they had changed their treatment behaviour due to the training content. They assessed the interactive simulator workshop semiquantitatively on a scale from 1 ("absolutely correct") to 7 ("not correct at all") as follows: Sepsis simulation training (SST) improves identification (mean+/-SD) (2.3 +/- 1.3) and treatment (2.5 +/- 1.2) of patients with severe sepsis, and SST including true-life scenarios is more appropriate than traditional lectures (1.5 +/- 0.7). CONCLUSION: The presented SST could be an effective way to train intensive care specialists in severe sepsis management.


Subject(s)
Education, Medical, Continuing , Sepsis/therapy , Anesthesia/methods , Computer Simulation , Germany , Health Knowledge, Attitudes, Practice , Humans , Sepsis/mortality
19.
Neuropharmacology ; 41(8): 1013-6, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11747906

ABSTRACT

The present study generated a polyclonal antibody (AP86/3) that recognises a peptide sequence of the h5-HT(3B) receptor subunit. Western blot analysis of homogenates prepared from cell lines expressing either homomeric (h5-HT(3A)) or heteromeric (h5-HT(3A/3B)) receptors, as well as immunocytochemical studies with the same cell lines, indicated that AP86/3 recognised, selectively, the 5-HT(3B) subunit. Immunohistochemical labelling was also apparent in cells in the rat hippocampus that displayed the distribution and morphology of interneurones.


Subject(s)
Antibodies/metabolism , Hippocampus/cytology , Hippocampus/immunology , Receptors, Serotonin/immunology , Receptors, Serotonin/metabolism , Animals , Antigen-Antibody Reactions , Cell Line , Humans , Immune Sera/metabolism , Immunohistochemistry , Male , Rabbits , Rats , Rats, Wistar , Receptors, Serotonin, 5-HT3
20.
Arch Biochem Biophys ; 393(1): 154-62, 2001 Sep 01.
Article in English | MEDLINE | ID: mdl-11516172

ABSTRACT

Suspension of human epidermal cells in methylcellulose-containing medium induces CYP1A1 by a mechanism requiring functional Ah receptor (AhR). In present work CYP1A1 mRNA was induced in a variety of cultured rat epithelial cells by suspension, but the induction was transient, with CYP1A1 mRNA reaching maximal levels by 5 h and disappearing by 12 h. Though the methylcellulose itself contained no detectable ligand, (a) suspension activated the AhR, as judged by mobility shift assays, (b) the AhR competitive inhibitor alpha-naphthoflavone inhibited suspension-mediated induction, and (c) induction was dependent upon dioxin responsive transcriptional elements in the CYP1A1 promoter. The rapid disappearance of CYP1A1 mRNA after 5 h of suspension was unaffected by the addition of TCDD but was prevented by the inclusion of the protein synthesis inhibitor cycloheximide. Thus the downregulation appears to be mediated by a novel short-lived protein induced or activated by suspension.


Subject(s)
Cytochrome P-450 CYP1A1/genetics , Animals , Base Sequence , Cells, Cultured , Culture Media , Cycloheximide/pharmacology , DNA Primers/genetics , Gene Expression/drug effects , Genes, Reporter , Keratinocytes/drug effects , Keratinocytes/metabolism , Methylcellulose , Polychlorinated Dibenzodioxins/pharmacology , Promoter Regions, Genetic , Protein Synthesis Inhibitors/pharmacology , RNA, Messenger/genetics , RNA, Messenger/metabolism , Rats , Receptors, Aryl Hydrocarbon/antagonists & inhibitors , Receptors, Aryl Hydrocarbon/metabolism
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