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1.
Adv Sci (Weinh) ; 10(8): e2206437, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36646499

ABSTRACT

The last 20 years have seen many publications investigating porous solids for gas adsorption and separation. The abundance of adsorbent materials (this work identifies 1608 materials for CO2 /N2 separation alone) provides a challenge to obtaining a comprehensive view of the field, identifying leading design strategies, and selecting materials for process modeling. In 2021, the empirical bound visualization technique was applied, analogous to the Robeson upper bound from membrane science, to alkane/alkene adsorbents. These bound visualizations reveal that adsorbent materials are limited by design trade-offs between capacity, selectivity, and heat of adsorption. The current work applies the bound visualization to adsorbents for a wider range of gas pairs, including CO2 , N2 , CH4 , H2 , Xe, O2 , and Kr. How this visual tool can identify leading materials and place new material discoveries in the context of the wider field is presented. The most promising current strategies for breaking design trade-offs are discussed, along with reproducibility of published adsorption literature, and the limitations of bound visualizations. It is hoped that this work inspires new materials that push the bounds of traditional trade-offs while also considering practical aspects critical to the use of materials on an industrial scale such as cost, stability, and sustainability.

2.
Brain Res ; 1629: 38-53, 2015 Dec 10.
Article in English | MEDLINE | ID: mdl-26453289

ABSTRACT

The brain circuits underlying tics in Tourette׳s syndrome (TS) are unknown but thought to involve cortico/amygdalo-striato-thalamo-cortical (CSTC) loop hyperactivity. We previously engineered a transgenic mouse "circuit model" of TS by expressing an artificial neuropotentiating transgene (encoding the cAMP-elevating, intracellular A1 subunit of cholera toxin) within a small population of dopamine D1 receptor-expressing somatosensory cortical and limbic neurons that hyperactivate cortico/amygdalostriatal glutamatergic output circuits thought to be hyperactive in TS and comorbid obsessive-compulsive (OC) disorders. As in TS, these D1CT-7 ("Ticcy") transgenic mice׳s tics were alleviated by the TS drugs clonidine and dopamine D2 receptor antagonists; and their chronic glutamate-excited striatal motor output was unbalanced toward hyperactivity of the motoric direct pathway and inactivity of the cataleptic indirect pathway. Here we have examined whether these mice׳s tics are countered by drugs that "break" sequential elements of their hyperactive cortical/amygdalar glutamatergic and efferent striatal circuit: anti-serotonoceptive and anti-noradrenoceptive corticostriatal glutamate output blockers (the serotonin 5-HT2a,c receptor antagonist ritanserin and the NE alpha-1 receptor antagonist prazosin); agmatinergic striatothalamic GABA output blockers (the presynaptic agmatine/imidazoline I1 receptor agonist moxonidine); and nigrostriatal dopamine output blockers (the presynaptic D2 receptor agonist bromocriptine). Each drug class alleviates tics in the Ticcy mice, suggesting a hyperglutamatergic CSTC "tic circuit" could exist in TS wherein cortical/amygdalar pyramidal projection neurons׳ glutamatergic overexcitation of both striatal output neurons and nigrostriatal dopaminergic modulatory neurons unbalances their circuit integration to excite striatothalamic output and create tics, and illuminating new TS drug strategies.


Subject(s)
Corpus Striatum/metabolism , Glutamic Acid/metabolism , Somatosensory Cortex/metabolism , Thalamic Nuclei/metabolism , Tics/metabolism , Tourette Syndrome/metabolism , Adrenergic alpha-1 Receptor Antagonists/pharmacology , Adrenergic alpha-1 Receptor Antagonists/therapeutic use , Animals , Corpus Striatum/drug effects , Disease Models, Animal , Dopamine Agonists/pharmacology , Dopamine Agonists/therapeutic use , Female , Mice , Mice, Inbred BALB C , Mice, Transgenic , Nerve Net/drug effects , Nerve Net/metabolism , Serotonin 5-HT2 Receptor Antagonists/pharmacology , Serotonin 5-HT2 Receptor Antagonists/therapeutic use , Somatosensory Cortex/drug effects , Thalamic Nuclei/drug effects , Tics/drug therapy , Tourette Syndrome/drug therapy
3.
Article in English | MEDLINE | ID: mdl-24110772

ABSTRACT

Utilising strategically positioned bed-mounted accelerometers, the Passive Sleep Actigraphy platform aims to deliver a non-contact method for identifying periods of wakefulness during night-time sleep. One of the key problems in developing data driven approaches for automatic sleep monitoring is managing the inherent sleep/wake class imbalance. In the current study, actigraphy data from three participants over a period of 30 days was collected. Upon examination, it was found that only 10% contained wake data. Consequently, this resulted in classifier overfitting to the majority class (sleep), thereby impeding the ability of the Passive Sleep Actigraphy platform to correctly identify periods of wakefulness during sleep; a key measure in the identification of sleep problems. Utilising Spread Subsample and Synthetic Minority Oversampling Techniques, this paper demonstrates a potential solution to this issue, reporting improvements of up to 28% in wake detection when compared to baseline data while maintaining an overall classifier accuracy of 90%.


Subject(s)
Actigraphy/methods , Sleep/physiology , Wakefulness/physiology , Accelerometry/instrumentation , Actigraphy/instrumentation , Adult , Female , Humans , Male , Polysomnography/methods , Time Factors , Young Adult
4.
Mamm Genome ; 24(3-4): 134-41, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23297074

ABSTRACT

Three genes, Mc1r, Agouti, and CBD103, interact in a type-switching process that controls much of the pigmentation variation observed in mammals. A deletion in the CBD103 gene is responsible for dominant black color in dogs, while the white-phased black bear ("spirit bear") of British Columbia, Canada, is the lightest documented color variant caused by a mutation in Mc1r. Rare all-white animals have recently been discovered in a new northeastern population of the coyote in insular Newfoundland and Labrador, Canada. To investigate the causative gene and mutation of white coat in coyotes, we sequenced the three type-switching genes in white and dark-phased animals from Newfoundland. The only sequence variants unambiguously associated with white color were in Mc1r, and one of these variants causes the amino acid variant R306Ter, a premature stop codon also linked to coat color in Golden Retrievers and other dogs with yellow/red coats. The allele carrying R306Ter in coyotes matches that in the Golden Retriever at other variable amino acid sites and hence may have originated in these dogs. Coyotes experienced introgression with wolves and dogs as they colonized northeastern North America, and coyote/Golden Retriever interactions have been observed in Newfoundland. We speculate that natural selection, with or without a founder effect, may contribute to the observed frequency of white coyotes in Newfoundland, as it has contributed to the high frequency of white bears, and of a domestic dog-derived CBD allele in gray wolves.


Subject(s)
Coyotes/genetics , Pigmentation/genetics , Polymorphism, Single Nucleotide , Receptor, Melanocortin, Type 1/genetics , Alleles , Animals , British Columbia , Codon, Nonsense , Dogs , Evolution, Molecular , Founder Effect , Genotype , Hair Color/genetics , Mutation , Newfoundland and Labrador , Phenotype , Selection, Genetic , Sequence Analysis, DNA
5.
Ageing Int ; 36(2): 217-231, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21660088

ABSTRACT

Approximately one in three people over the age of 65 will fall each year, resulting in significant financial, physical, and emotional cost on the individual, their family, and society. Currently, falls are managed using on-body sensors and alarm pendants to notify others when a falls event occurs. However these technologies do not prevent a fall from occurring. There is now a growing focus on falls risk assessment and preventative interventions. Falls risk is currently assessed in a clinical setting by expert physiotherapists, geriatricians, or occupational therapists following the occurrence of an injurious fall. As the population ages, this reactive model of care will become increasingly unsatisfactory, and a proactive community-based prevention strategy will be required. Recent advances in technology can support this new model of care by enabling community-based practitioners to perform tests that previously required expensive technology or expert interpretation. Gait and balance impairment is one of the most common risk factors for falls. This paper reviews the current technical and non-technical gait and balance assessments, discusses how low-cost technology can be applied to objectively administer and interpret these tests in the community, and reports on recent research where body-worn sensors have been utilized. It also discusses the barriers to adoption in the community and proposes ethnographic research as a method to investigate solutions to these barriers.

6.
Article in English | MEDLINE | ID: mdl-21096871

ABSTRACT

Wireless sensor networks have become increasingly common in everyday applications due to decreasing technology costs and improved product performance, robustness and extensibility. Wearable physiological monitoring systems have been utilized in a variety of studies, particularly those investigating ECG or EMG during human movement or sleep monitoring. These systems require extensive validation to ensure accurate and repeatable functionality. Here we validate the physiological signals (EMG, ECG and GSR) of the SHIMMER (Sensing Health with Intelligence, Modularity, Mobility and Experimental Reusability) against known commercial systems. Signals recorded by the SHIMMER EMG, ECG and GSR daughter-boards were found to compare well to those obtained by commercial systems.


Subject(s)
Monitoring, Physiologic/instrumentation , Algorithms , Biomechanical Phenomena , Electrocardiography/instrumentation , Electromyography/instrumentation , Humans , Movement , Sleep
7.
Appl Ergon ; 40(3): 419-23, 2009 May.
Article in English | MEDLINE | ID: mdl-19084818

ABSTRACT

The objective of this study was to identify major occupational factors that were significantly correlated with back pain in pregnant women working in higher education, health care and service areas. A total of 73 working pregnant women were surveyed using questionnaires specifically designed for evaluating correlations between occupational factors and severity of back pain; 37 women were interviewed at both 20 and 34 weeks of pregnancy, 17 at 20 weeks only, and 19 were interviewed at 34 weeks only. "Rest breaks allowed" and "job autonomy" were negatively correlated with severity of back pain at 20 weeks of pregnancy. "Staying in a confined area" and "having restricted space" were positively correlated with severity of back pain at 34 weeks of pregnancy. The study suggests that allowing pregnant women to take more rest breaks and to have more job autonomy may reduce the severity of back pain during early pregnancy, and that allowing movement outside the working area and providing less restricted space may reduce back pain during late pregnancy.


Subject(s)
Back Pain/etiology , Occupational Exposure , Adult , Back Pain/epidemiology , Ergonomics , Female , Humans , Interviews as Topic , Ontario/epidemiology , Pregnancy , Risk Factors , Surveys and Questionnaires
8.
Article in English | MEDLINE | ID: mdl-18002831

ABSTRACT

Using five different commercially available class one and class two Bluetooth dongles a total of seven homes which represented a cross section of typical Irish homes were surveyed to determine the effect of construction methods, house size, sensor placement, host placement, antenna design and RF interference had on the link quality of Bluetooth enabled sensors. The results obtained indicates there is high variability in the link quality which is determined by the quality of the BT radio, placement of the antenna on both the master and slave, the number of walls which must be penetrated and the construction materials used in the wall. The placement of the sensor was the single biggest factor in determining the link quality. The type of construction used in the interior walls has significant influence also. The final factor of significant influence was the type of antenna used on the Bluetooth dongle. The use of an external antenna gave significantly better range performance than an internal antenna.


Subject(s)
Construction Materials , Housing , Local Area Networks , Humans , Ireland
9.
Can J Physiol Pharmacol ; 83(7): 625-33, 2005 Jul.
Article in English | MEDLINE | ID: mdl-16091788

ABSTRACT

This study examined the effects of aerobic conditioning during the second and third trimesters of human pregnancy on ventilatory responses to graded cycling. Previously sedentary pregnant women were assigned randomly to an exercise group (n = 14) or a nonexercising control group (n = 14). Data were collected at 15-17 weeks, 25-27 weeks and 34-36 weeks of pregnancy. Testing involved 20 W.min-1 increases in work rate to a heart rate of 170 beats.min-1 and (or) volitional fatigue. Breath-by-breath ventilatory and alveolar gas exchange measurements were compared at rest, a standard submaximal .VO2 and peak exercise. Within both groups, resting .V(E), .V(A), and V(T)/T(I) increased significantly with advancing gestation. Peak work rate, O2 pulse (.VO2/HR), .V(E), .V(A) respiratory rate, V(T)/T(I), .VO2, .VCO2, and the ventilatory threshold (T(vent)) were increased after physical conditioning. Chronic maternal exercise has no significant effect on pregnancy-induced changes in ventilation and (or) alveolar gas exchange at rest or during standard submaximal exercise. Training-induced increases in T(vent) and peak oxygen pulse support the efficacy of prenatal fitness programs to improve maternal work capacity.


Subject(s)
Exercise/physiology , Physical Fitness/physiology , Pregnancy/metabolism , Pulmonary Alveoli/physiology , Pulmonary Gas Exchange/physiology , Adult , Anaerobic Threshold/physiology , Exercise Test , Female , Heart Rate/physiology , Humans , Oxygen Consumption/physiology , Respiratory Mechanics/physiology
11.
J Appl Physiol (1985) ; 95(6): 2321-7, 2003 Dec.
Article in English | MEDLINE | ID: mdl-12959950

ABSTRACT

This study tested the hypothesis that human pregnancy alters fluid and electrolyte regulation responses to acute short-term exercise. Responses of 22 healthy pregnant women (PG; gestational age, 37.0 +/- 0.2 wk) and 17 nonpregnant controls (CG) were compared at rest and during cycling at 70 and 110% of the ventilatory threshold (VT). At rest, ANG II concentration was significantly (P < 0.05) higher in PG vs. CG, whereas plasma osmolality and concentrations of AVP, sodium, and potassium were significantly lower. Atrial natriuretic peptide concentration at rest was similar between groups. ANG II and AVP concentrations increased significantly from rest to 110% VT in CG only, whereas increases in atrial natriuretic peptide concentration were similar between groups. Increases in osmolality, and total protein and albumin concentrations from rest to both work rates were similar between the two groups. PG and CG exhibited similar shifts in fluid during acute short-term exercise, but the increases in ANG II and AVP were absent and attenuated, respectively, during pregnancy. This was attributed to the significantly augmented fluid volume state already present at rest in late gestation.


Subject(s)
Exercise/physiology , Pregnancy/physiology , Water-Electrolyte Balance/physiology , Adult , Albumins/metabolism , Anaerobic Threshold/physiology , Angiotensin II/pharmacology , Arginine Vasopressin/pharmacology , Carbon Dioxide/blood , Electrolytes/blood , Exercise Test , Female , Heart Rate/physiology , Humans , Hydrogen-Ion Concentration , Oxygen/blood , Plasma Volume/physiology , Progesterone/blood , Renin-Angiotensin System/physiology , Respiratory Mechanics/physiology , Vasoconstrictor Agents/pharmacology
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