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1.
Brain Inj ; 35(11): 1390-1401, 2021 09 19.
Article in English | MEDLINE | ID: mdl-34487459

ABSTRACT

BACKGROUND: While difficulties regulating emotions are almost ubiquitous after traumatic brain injury (TBI), remediation techniques are limited. Heart-rate variability (HRV) is a physiological measure of emotion regulation and can be modified using biofeedback training. The aim of the current study was to evaluate the efficacy of repeated biofeedback training for improving emotion regulation difficulties following TBI. DESIGN: Fifty adults with severe TBI were allocated to either biofeedback or waitlist conditions. Treatment consisted of six biofeedback sessions whereby participants were taught to breathe at their resonant frequency. Outcomes included changes in physiological and subjective reactivity to anger-induction, emotional well-being, and physiology at rest, together with symptoms of psychological distress and sleep disturbances (ACTRN12618002031246). RESULTS: While biofeedback led to reduced skin conductance, it did not affect any other objective or subjective response to the mood induction procedure. Biofeedback led to fewer sleep disturbances, and reduced negative mood valence and depression during follow-up. CONCLUSIONS: HRV biofeedback training is a feasible technique following TBI that transfers to improved symptoms of general emotional well-being, psychological distress, and sleep. Biofeedback does not transfer to a laboratory-based emotional provocation task. HRV biofeedback training may represent a novel adjunct for generalized emotional difficulties following injury.


Subject(s)
Biofeedback, Psychology , Brain Injuries, Traumatic , Adult , Anger , Emotions , Heart Rate , Humans
2.
Phys Rev Lett ; 121(12): 127705, 2018 Sep 21.
Article in English | MEDLINE | ID: mdl-30296125

ABSTRACT

We study transport mediated by Andreev bound states formed in InSb nanowire quantum dots. Two kinds of superconducting source and drain contacts are used: epitaxial Al/InSb devices exhibit a doubling of tunneling resonances, while, in NbTiN/InSb devices, Andreev spectra of the dot appear to be replicated multiple times at increasing source-drain bias voltages. In both devices, a mirage of a crowded spectrum is created. To describe the observations a model is developed that combines the effects of a soft induced gap and of additional Andreev bound states both in the quantum dot and in the finite regions of the nanowire adjacent to the quantum dot. Understanding of Andreev spectroscopy is important for the correct interpretation of Majorana experiments done on the same structures.

3.
Nat Commun ; 7: 11993, 2016 06 27.
Article in English | MEDLINE | ID: mdl-27346655

ABSTRACT

The discovery of topological insulators, materials with bulk band gaps and protected cross-gap surface states in compounds such as Bi2Se3, has generated much interest in identifying topological surface states (TSSs) in other classes of materials. In particular, recent theoretical calculations suggest that TSSs may be found in half-Heusler ternary compounds. If experimentally realizable, this would provide a materials platform for entirely new heterostructure spintronic devices that make use of the structurally identical but electronically varied nature of Heusler compounds. Here we show the presence of a TSS in epitaxially grown thin films of the half-Heusler compound PtLuSb. Spin- and angle-resolved photoemission spectroscopy, complemented by theoretical calculations, reveals a surface state with linear dispersion and a helical tangential spin texture consistent with previous predictions. This experimental verification of topological behaviour is a significant step forward in establishing half-Heusler compounds as a viable material system for future spintronic devices.

4.
Ecol Appl ; 17(1): 101-17, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17479838

ABSTRACT

The importance of efficaciously assessing the risk for introduction and establishment of pest species is an increasingly important ecological and economic issue. Evaluation of climate is fundamental to determining the potential success of an introduced or invasive insect pest. However, evaluating climatic suitability poses substantial difficulties; climate can be measured and assessed in a bewildering array of ways. Some physiological filter, in essence a lens that focuses climate through the requirements and constraints of a potential pest introduction, is required. Difficulties in assessing climate suitability are further exacerbated by the effects of climate change. Gypsy moth (Lymantria dispar L.) is an exotic, tree-defoliating insect that is frequently introduced into the western United States. In spite of an abundance of potential host species, these introductions have yet to result in established populations. The success of eradication efforts and the unsuccessful establishment of many detected and undetected introductions may be related to an inhospitable climate. Climatic suitability for gypsy moth in the western United States, however, is potentially improving, perhaps rapidly, due to a general warming trend that began in the mid 1970s and continues today. In this work, we describe the application of a physiologically based climate suitability model for evaluating risk of gypsy moth establishment on a landscape level. Development of this risk assessment system first required amassing databases that integrated the gypsy moth climatic assessment model, with host species distributions, and climate (historical, present, and future). This integrated system was then used to evaluate climate change scenarios for native host species in Utah, with the result that risk of establishment will dramatically increase during the remainder of the 21st century under reasonable climate change scenarios. We then applied the risk assessment system to several case histories of detected gypsy moth introductions in Utah. These applications demonstrated the general utility of the system for predicting risk of establishment and for designing improved risk detection strategies.


Subject(s)
Climate , Moths/physiology , Animals , Models, Theoretical , Risk Assessment , Utah
5.
Bull Math Biol ; 63(3): 573-95, 2001 May.
Article in English | MEDLINE | ID: mdl-11374306

ABSTRACT

In this paper we discuss how seasonal temperature variation and life-stage specific developmental thresholds that cause quiescence can synchronize the seasonal development of exothermic organisms. Using a simple aging model it is shown that minimal seasonal temperature variation and periods of quiescence during extreme temperature conditions are sufficient to establish stable, univoltine ovipositional cycles. Quiescence induced by life-stage specific developmental thresholds, in fact, promotes synchronous oviposition and emergence. The mountain pine beetle, an important insect living in extreme temperature conditions and showing no evidence of diapause, invites direct application of this model. Simulations using mountain pine beetle parameters are used to determine temperature regimes for which stable ovipositional cycles exist.


Subject(s)
Climate , Coleoptera/growth & development , Models, Biological , Animals , Computer Simulation , Life Cycle Stages/physiology , Oviposition/physiology , Seasons , Temperature
6.
Bull Math Biol ; 62(5): 977-98, 2000 Sep.
Article in English | MEDLINE | ID: mdl-11016093

ABSTRACT

In this paper we discuss the effects of yearly temperature variation on the development and seasonal occurrence of poikiliothermic organisms with multiple life stages. The study of voltinism in the mountain pine beetle (Dendroctonus ponderosae Hopkins), an important forest insect living in extreme temperature environments and exhibiting no diapause, provides a motivational example. Using a minimal model for the rates of aging it is shown that seasonal temperature variation and minimal stage-specific differences in rates of aging are sufficient to create stable uni- and multi-voltine oviposition cycles. In fact, these cycles are attracting and therefore provide an exogenous mechanism for synchronizing whole populations of organisms. Structural stability arguments are used to extend the results to more general life systems.


Subject(s)
Life Cycle Stages , Seasons , Aging , Animals , Coleoptera/growth & development , Coleoptera/physiology , Female , Models, Biological , Models, Theoretical , Oviposition , Temperature
7.
Psychol Rep ; 81(1): 79-90, 1997 Aug.
Article in English | MEDLINE | ID: mdl-9293196

ABSTRACT

52 members of the college community at a small liberal arts university (Ages 25-72) were administered a 60-min. battery of tests measuring different aspects of cognitive performance. Stepwise regression equations detected significant relationships between the predictor variables of age and education and measures of the WAIS-R, the Logical Memory subtests and Trails A. Age predicted performance on Trails A, the Digit Symbol subtest of the WAIS-R, the Logical Memory II component of the Wechsler Memory Scale-R, some measures of the Wisconsin Card Sorting Test, and Full Scale WAIS-R IQ. Education was a significant predictor of performance on the remaining WAIS-R subtests and the Failure. To Maintain Response Sets measure of the card sorting. However, the results of the present study also suggest that over-all cognitive decline with advancing age is not an eventuality, at least among the highly educated, intellectually active individuals.


Subject(s)
Aging/psychology , Faculty , Intelligence , Adult , Aged , Educational Status , Humans , Middle Aged , Psychometrics , Wechsler Scales/statistics & numerical data
8.
Health Bull (Edinb) ; 55(1): 52-7, 1997 Jan.
Article in English | MEDLINE | ID: mdl-9090179

ABSTRACT

OBJECTIVES: Studies have suggested that routine chest x-ray is never indicated but all new attenders at our day hospitals have a chest x-ray carried out. Our aim was to determine if this investigation altered the clinical management of patients and to try to select those patients in whom a chest x-ray is indicated. DESIGN: A prospective study was carried out over a 7 month period from February to September 1995. All new patients had cardiorespiratory symptoms/signs documented and a management plan made. A chest x-ray was then carried out and change in management as a result of the x-ray report noted. SETTING: Knightswood and Drumchapel Geriatric Day Hospitals, West Glasgow University NHS Trust. SUBJECTS: All new Day Hospital attenders. RESULTS: Of 207 new Day Hospital attenders, 53 had no clinical indication for a chest x-ray and although 70% had an abnormal film in no case was patient management changed as a result of this. A chest x-ray was indicated in 154 patients and of these 114 (74%) had an abnormal film with a resultant change in management in 23 patients (this comprised either a change in drug treatment or a further investigation.) Of those whose management was changed as a result of the x-ray report 61% had respiratory symptoms. CONCLUSION: We would recommend that chest x-ray should be performed in those patients who have a clear clinical indication and that the diagnostic yield is highest in the presence of respiratory symptoms or signs.


Subject(s)
Day Care, Medical , Geriatrics , Patient Admission , Patient Selection , Radiography, Thoracic/standards , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Prospective Studies , Reproducibility of Results
10.
Neuropeptides ; 30(6): 541-5, 1996 Dec.
Article in English | MEDLINE | ID: mdl-9004251

ABSTRACT

Rats were administered saline or 10 micrograms of the ACTH4-9 analog ORG 2766 on alternate days for 160 days (i.e. 80 injections total). Behavioral assessments began 1 week later. Locomotor competence was assessed by examining the number of slips and falls made by the animals on a rotating rod. The rats were also trained on a position task and 10 subsequent position reversals in a 'T' shaped water maze. Exposure to ORG 2766 failed to affect either locomotor competence or the overall number of errors committed while learning the original position habit and 10 reversals. However, the response accuracy of the ORG 2766-treated animals on trial 2 of the reversals was equivalent to that expected by chance (58% correct choices), whereas saline-treated animals effectively altered their behavior after experiencing nonreinforcement on the initial trial of a reversal (77% correct choices). This result is consistent with other observations revealing that ORG 2766 can influence attention and, therefore, some cognitive functions.


Subject(s)
Adrenocorticotropic Hormone/analogs & derivatives , Anticonvulsants/pharmacology , Maze Learning/drug effects , Motor Activity/drug effects , Peptide Fragments/pharmacology , Reversal Learning/drug effects , Adrenocorticotropic Hormone/administration & dosage , Adrenocorticotropic Hormone/pharmacology , Analysis of Variance , Animals , Anticonvulsants/administration & dosage , Cohort Studies , Female , Injections, Subcutaneous , Male , Maze Learning/physiology , Motor Activity/physiology , Peptide Fragments/administration & dosage , Random Allocation , Rats , Reversal Learning/physiology , Time Factors
11.
Physician Exec ; 20(10): 19-21, 1994 Oct.
Article in English | MEDLINE | ID: mdl-10138290

ABSTRACT

A host of historical and practical precedents have made hospitals responsible for the quality of care rendered within their facilities. The medical staff and the board of trustees share in this responsibility. Increasing demands for demonstrative evidence of the quality of care in an institution have made the process data-based. There is no substitute for specific data on the performance of both the hospital and its providers in the delivery of care. The trick, however, is in presenting this information to the medical staff and the board in a fashion that will be understandable and that will still maintain confidentiality of provider and patient. The authors offer a presentation system that has met with success in their community hospital.


Subject(s)
Computer Graphics , Governing Board , Medical Staff, Hospital/education , Quality of Health Care/standards , Data Interpretation, Statistical , Documentation , Joint Commission on Accreditation of Healthcare Organizations , United States
12.
Physician Exec ; 19(4): 37-8, 1993.
Article in English | MEDLINE | ID: mdl-10127412

ABSTRACT

External forces continue to dictate the necessity of delivering high-quality health care along with methods of proving that the claimed quality is attained. Gone are the days when both the institution and its practitioners could answer quality questions simply by stating that they were delivering excellent health care to their patient population. The federal government, via the Health Care Financing Administration, and the Joint Commission on Accreditation of Healthcare Organizations (JCAHO) are mandating that institutions prove, without question, that they are delivering health care of the highest quality. The essential key to attaining these goals is cooperative private practitioners.


Subject(s)
Medical Staff, Hospital/standards , Quality Assurance, Health Care/organization & administration , Humans , Interprofessional Relations , Medical Staff, Hospital/psychology , Motivation , Planning Techniques , United States
13.
Physician Exec ; 19(2): 49-51, 1993.
Article in English | MEDLINE | ID: mdl-10129392

ABSTRACT

From a practical viewpoint, the close relationships among utilization review, quality assurance/improvement, infection control, discharge planning, social services, and medical records makes it impossible to separate them. Case management combines these traditionally isolated hospital functions into one department in order to perform many related functions simultaneously. It provides a much more effective and efficient method than can be accomplished by the traditional institutional approach.


Subject(s)
Centralized Hospital Services/organization & administration , Efficiency, Organizational , Interdepartmental Relations , Patient Care Planning/organization & administration , Kentucky , Medical Records Department, Hospital/organization & administration , Nursing Staff, Hospital/organization & administration , Patient Discharge , Planning Techniques , Social Work Department, Hospital/organization & administration , Utilization Review/organization & administration
14.
Cancer Genet Cytogenet ; 45(1): 41-7, 1990 Mar.
Article in English | MEDLINE | ID: mdl-2302684

ABSTRACT

Loss of the Y chromosome in meningiomas from 17 male patients was examined by cytogenetic analysis and by Southern blot hybridization with a series of Y-specific DNA probes. Cytogenetic analysis revealed loss of the Y chromosome in seven of 17 (41%) of the tumors whereas Southern blot hybridization showed loss of Y-associated sequences in only three of 17 (18%). Although the incidence of Y-chromosome loss was less by Southern blot hybridization than by cytogenetic analysis, the finding that loss of Y is present in the original uncultured tumor specimen suggests that a gene or genes on the Y chromosome may play a role in growth control of meningioma cells, and loss of this gene may be associated with tumor progression. The difference in the incidence of Y loss between the two methods indicates that both methods should be used when examining chromosome losses.


Subject(s)
Chromosome Deletion , Meningeal Neoplasms/genetics , Meningioma/genetics , Y Chromosome , Adult , Aged , Blotting, Southern , DNA Probes , DNA, Neoplasm/genetics , Humans , Karyotyping , Male , Middle Aged
16.
Am J Public Health ; 74(7): 660-6, 1984 Jul.
Article in English | MEDLINE | ID: mdl-6611092

ABSTRACT

Patterns of initiation, continued use, and decline in drug use are described on the basis of detailed drug histories in a longitudinal cohort representative of former New York State adolescents. In this cohort, the period of major risk for initiation to cigarettes, alcohol, and marijuana, is completed for the most part by age 20, and to illicit drugs other than cocaine by age 21. Those who have not experimented with any of these substances by that age are unlikely to do so thereafter. Initiation into prescribed psychoactive drugs occurs at a later age than for the licit and illicit drugs and continues through the age period covered by the survey. A potential maturational trend in marijuana use in this cohort is apparent with a decline beginning approximately at age 22.5 for most usage patterns. The periods of highest marijuana and alcohol usage decline beginning at ages 20-21 and contrast sharply with cigarettes which exhibit climbing rates of highest use through the end of the surveillance period (age 25). Overall patterns are similar for men and women, with men initiating all drugs at higher rates than women, except for prescribed psychoactives .


Subject(s)
Illicit Drugs , Pharmaceutical Preparations , Psychotropic Drugs , Substance-Related Disorders/epidemiology , Adolescent , Adult , Alcohol Drinking , Child , Female , Humans , Male , Marijuana Abuse/epidemiology , New York , Risk , Smoking
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