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96 records – page 1 of 10.

A 1-year, three-couple expedition as a crew analog for a Mars mission.

https://arctichealth.org/en/permalink/ahliterature31234
Source
Environ Behav. 2002 Sep;34(5):672-700
Publication Type
Article
Date
Sep-2002
Author
Gloria R Leon
Mera M Atlis
Deniz S Ones
Graeme Magor
Author Affiliation
Clinical Psychology, University of Minnesota, USA.
Source
Environ Behav. 2002 Sep;34(5):672-700
Date
Sep-2002
Language
English
Publication Type
Article
Keywords
Adaptation, Psychological
Adult
Aerospace Medicine
Arctic Regions
Astronauts - psychology
Canada
Child
Cold Climate
Darkness
Expeditions
Female
Humans
Interpersonal Relations
Male
Mars
Norway
Personality
Personnel Selection
Questionnaires
Social Isolation
Space Simulation
Spouses - psychology
Abstract
This study assessed the intrapersonal and interpersonal functioning of a three-couple expedition group that included a 2 1/2-year-old child which was ice-locked on a boat in the High Arctic during a major portion of the expedition. Personality assessment indicated that team members were generally well adjusted, scoring relatively higher on well-being and achievement and relatively lower on stress reactivity. Weekly mood ratings showed that the group exhibited significantly higher positive than negative affect. Reported negative events were relatively most frequent at the beginning of the Arctic stay and toward the end of the darkness period and were lowest during the initial darkness interval. The period of darkness had both a salutary and negative impact. A highly important means of coping with stress was seeking emotional support from one's partner. Selection of couples with strong bonds with their partner appears to be one viable approach for crew selection for long-duration missions.
PubMed ID
12481801 View in PubMed
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Aland eye disease (Forsius-Eriksson-Miyake syndrome) with probability established in a Danish family.

https://arctichealth.org/en/permalink/ahliterature51305
Source
Acta Ophthalmol (Copenh). 1990 Jun;68(3):281-91
Publication Type
Article
Date
Jun-1990
Author
T. Rosenberg
M. Schwartz
S E Simonsen
Author Affiliation
National Eye Clinic for the Visually Impaired, Copenhagen, Denmark.
Source
Acta Ophthalmol (Copenh). 1990 Jun;68(3):281-91
Date
Jun-1990
Language
English
Publication Type
Article
Keywords
Adolescent
Adult
Aged
Aged, 80 and over
Dark Adaptation
Denmark
Electroretinography
Female
Fundus Oculi
Heterozygote Detection
Humans
Male
Middle Aged
Myopia - complications - congenital - genetics
Night Blindness - complications - congenital - genetics
Nystagmus, Pathologic - complications - congenital - genetics
Pedigree
Photoreceptors - physiopathology
Pigmentation
Research Support, Non-U.S. Gov't
Retinal Diseases - congenital - diagnosis - genetics
Sex Chromosome Aberrations
Syndrome
Visual acuity
X Chromosome
Abstract
A reinvestigation of a Danish family with X-linked inherited congenital nystagmus through 6 generations revealed a congenital stationary retinal dysfunction syndrome with characteristics of both incomplete congenital stationary night blindness and Aland Eye Disease. In spite of rather uniform electrophysiological findings in our patients, this retinal disorder which affects both cones and rods demonstrated considerable intrafamilial diversity with respect to visual acuity, nystagmus, refractive state and fundus pigmentation.
PubMed ID
2392903 View in PubMed
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Alterations in serum melatonin and sleep in individuals in a sub-arctic region from winter to spring.

https://arctichealth.org/en/permalink/ahliterature183029
Source
Int J Circumpolar Health. 2003 Sep;62(3):242-54
Publication Type
Article
Date
Sep-2003
Author
Trond Bratlid
Björn Wahlund
Author Affiliation
Psychiatric Department, University of Tromsø, Norway. trond.bratlid@rito.no
Source
Int J Circumpolar Health. 2003 Sep;62(3):242-54
Date
Sep-2003
Language
English
Publication Type
Article
Keywords
Adult
Aged
Arctic Regions
Circadian Rhythm - physiology
Darkness
Female
Humans
Male
Melatonin - blood - secretion
Middle Aged
Seasons
Sleep
Sleep Initiation and Maintenance Disorders - blood - ethnology - physiopathology
Abstract
In a sub-arctic region at 69 degrees N, seven individuals with self-reported insomnia during the 'dark period' and seven without, were followed with repeated measures of melatonin and questioned on ten different sleep variables, from the beginning of January to the vernal equinox in March.
The distribution of melatonin over a 24-hour period (five time points) indicated an increase in melatonin levels in both groups in the middle of January and a decrease at the time of year when the sun first rises over the horizon (23rd-24th of January). Moreover, an indication of a delayed phase shift of melatonin secretion was found during the dark period, which returned to "normal" secretion during the night at the equinox in March. Individuals with sleep problems had a slower return to "normal" melatonin secretion than those without sleep problems. A positive correlation between morning tiredness and morning levels of melatonin was found among individuals with sleep disturbances, but not in controls.
This study indicates changes in the internal circadian rhythm in humans at the end of the annual dark period of winter when there is a rapid increase in the number of hours of sunlight. For vulnerable individuals, the disturbance in sleep, and in particlar morning tiredness, lasts at least until the vernal equinox in March.
PubMed ID
14594199 View in PubMed
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Alternating light-darkness-influenced human electrocardiographic magnetoreception in association with geomagnetic pulsations.

https://arctichealth.org/en/permalink/ahliterature6054
Source
Biomed Pharmacother. 2001;55 Suppl 1:63s-75s
Publication Type
Article
Date
2001
Author
K. Otsuka
S. Oinuma
G. Cornélissen
A. Weydahl
Y. Ichimaru
M. Kobayashi
S. Yano
B. Holmeslet
T L Hansen
G. Mitsutake
M J Engebretson
O. Schwartzkopff
F. Halberg
Author Affiliation
Department of Medicine, Tokyo Women's Medical University, School of Medicine, Daini Hospital, Nishiogu, Japan. frtotk99@ba2.so-net.ne.jp
Source
Biomed Pharmacother. 2001;55 Suppl 1:63s-75s
Date
2001
Language
English
Publication Type
Article
Keywords
Adult
Arctic Regions
Cardiovascular Physiology - radiation effects
Darkness
Electrocardiography - radiation effects
Electromagnetic fields
Female
Heart Rate - physiology
Humans
Light
Male
Middle Aged
Research Support, Non-U.S. Gov't
Seasons
Abstract
Geomagnetic variations of partly interplanetary origin, with cyclic signatures in human affairs and pathology include the incidence of various diseases, regarding which this study of healthy subjects attempted to determine an underlying mechanism by worldwide archival and physiological monitoring, notably of heart rate variability (HRV). In the past half-century, the possible health and other hazards of natural, solar variability-driven temporal variations in the earth's magnetic field have become a controversial subject in view of the inconsistent results. Some well-documented claims of associations between geomagnetic storms and myocardial infarction or stroke have been rejected by a study based on more comprehensive data analyzed by rigorous methods - covering, however, only part of a solar cycle in only part of a hemisphere. It seems possible that inter-solar cycle and geographic variability, if not geographic differences, may account for discrepancies. Herein, we examine the start of a planetary study on any influence of geomagnetic disturbances that are most pronounced in the auroral oval, on human HRV. The magnetic field variations exhibit complex spectra and include the frequency band between 0.001-10 Hz, which is regarded as ultra-low frequency by physicists. Since the 'ultra-low-frequency' range, like other endpoints used in cardiology, refers to much higher frequencies than the about-yearly changes that are here shown to play a role in environmental-organismic interactions revealed by HRV, the current designations used in cardiology are all placed in quotation marks to indicate the need for possible revision. Whether or not this suggestion has an immediate response, we have pointed to a need for the development of instrumentation and software that renders the assessment of circadian, infradian and even infra-annual (truly low frequency) modulations routinely feasible. HRV was examined on the basis of nearly continuous 7-day records by ECG between December 10, 1998, and November 2, 2000, on 19 clinically healthy subjects, 21 to 54 years of age, in Alta, Norway. A geomagnetic record was obtained from the Auroral Observatory of the University of Tromsø. First, frequency-domain measures of HRV were compared for each person in 24-hour spans of high geomagnetic disturbance versus quiet conditions. Second, cross-spectra between geomagnetic activity and HRV measures were quantified via the squared coherence spectrum using 7-day time series. A 7.5% increase in the 24-hour average of heart rate, HR (P = 0.00020) and a decrease in HRV were documented on days of high geomagnetic disturbance. The decrease in HRV was validated statistically for the 'total frequency', 'TF' endpoint (18.6% decrease, P= 0.00009). The decrease in spectral power was found primarily in the 'circaminutan frequency', 'VLF' (21.9% decrease, P
PubMed ID
11774870 View in PubMed
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Apollo-Soyuz light-flash observations.

https://arctichealth.org/en/permalink/ahliterature5367
Source
Life Sci Space Res. 1977;15:141-6
Publication Type
Article
Date
1977
Author
T F Budinger
C A Tobias
R H Huesman
F T Upham
T F Wieskamp
R A Hoffman
Author Affiliation
Lawrence Berkeley Laboratory, University of California, Berkeley, Calif., USA.
Source
Life Sci Space Res. 1977;15:141-6
Date
1977
Language
English
Publication Type
Article
Keywords
Arctic Regions
Atlantic Ocean
Cosmic Radiation
Dark Adaptation
Heavy Ions
Humans
Light
Magnetics
Phosphenes - physiology
Protons
Retina - radiation effects
Solar Activity
South America
Space Flight
Vision - radiation effects
Visual Perception - radiation effects
Weightlessness
Abstract
While dark adapted, two Apollo-Soyuz astronauts saw eighty-two light flash events during a complete 51 degrees orbit which passed near the north magnetic pole and through the South Atlantic Anomaly. The frequency of events at the polar parts of the orbit is 25 times that noted in equatorial latitudes and no increased frequency was noted in the South Atlantic Anomaly at the 225-km altitude. The expected flux of heavy particles at the northern and southern points is 1-2 min-1 per eye, and the efficiency for seeing HZE particles which were below the Cerenkov threshold is 50%.
PubMed ID
11958208 View in PubMed
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Arctic cognition: a study of cognitive performance in summer and winter at 69 degrees N.

https://arctichealth.org/en/permalink/ahliterature3317
Source
Appl Cogn Psychol. 1999 Dec;13(6):561-80
Publication Type
Article
Date
Dec-1999
Author
T. Brennen
M. Martinussen
B O Hansen
O. Hjemdal
Author Affiliation
University of Tromso, Norway. Timb@psyk.uit.no
Source
Appl Cogn Psychol. 1999 Dec;13(6):561-80
Date
Dec-1999
Language
English
Publication Type
Article
Keywords
Adolescent
Adult
Arctic Regions
Attention
Cognition
Comparative Study
Darkness
Female
Humans
Light
Male
Memory
Middle Aged
Norway
Periodicity
Psychological Tests
Reaction Time
Research Support, Non-U.S. Gov't
Seasonal Affective Disorder - psychology
Seasons
Abstract
Evidence has accumulated over the past 15 years that affect in humans is cyclical. In winter there is a tendency to depression, with remission in summer, and this effect is stronger at higher latitudes. In order to determine whether human cognition is similarly rhythmical, this study investigated the cognitive processes of 100 participants living at 69 degrees N. Participants were tested in summer and winter on a range of cognitive tasks, including verbal memory, attention and simple reaction time tasks. The seasonally counterbalanced design and the very northerly latitude of this study provide optimal conditions for detecting impaired cognitive performance in winter, and the conclusion is negative: of five tasks with seasonal effects, four had disadvantages in summer. Like the menstrual cycle, the circannual cycle appears to influence mood but not cognition.
PubMed ID
11543349 View in PubMed
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Assay of melatonin and its metabolites: results in normal and unusual environments.

https://arctichealth.org/en/permalink/ahliterature237843
Source
J Neural Transm Suppl. 1986;21:11-33
Publication Type
Article
Date
1986
Author
J. Arendt
Source
J Neural Transm Suppl. 1986;21:11-33
Date
1986
Language
English
Publication Type
Article
Keywords
Animals
Arctic Regions
Chromatography, High Pressure Liquid - methods
Circadian Rhythm
Climate
Darkness
Environment
Gas Chromatography-Mass Spectrometry - methods
Humans
Light
Melatonin - analogs & derivatives - blood - metabolism
Microclimate
Pineal Gland - physiology
Reference Values
Abstract
The pineal gland, via its hormone melatonin, is of major importance in the transduction of photoperiodic information in animals. It is concerned both with the synchronisation of annual cycles in photoperiodic mammals and with regulation of circadian rhythmicity in lower vertebrates. Its role, if any, in mammalian circadian systems is still speculative. By analogy with animal work the function of the human pineal is most likely to be concerned with seasonal and circadian rhythms. The study of human pineal function depends heavily on the measurement of melatonin in plasma or urine. Radioimmunoassay (RIA) and gaschromatography-mass-spectrometry (GCMS) have been successfully employed to establish the basic 24-hour rhythm. GCMS has also served to validate RIA. Following early work the reported human plasma levels of melatonin have stabilized approximately at less than 20 pg/ml in daytime with mean night time levels around 40-80 pg/ml. The high sensitivity of GCMS measures daytime levels of 2-5 pg/ml. With confidence established in melatonin assays, its physiological and pathological variations can be investigated in full. Development of assays for urinary melatonin metabolites has made possible the longterm study of circadian variations in different environments. The rhythm of melatonin production can be dissociated from the sleep wake cycle in environmental isolation and behaves like a "strong" oscillator variable. In the unusual social and photoperiodic conditions of Antarctica it remains strongly entrained to the 24 hour day. Whilst measurement of melatonin can provide circumstantial evidence of its function, abolition of its production and its administration in humans can uncover causal relationships. The effects of abolition of the melatonin rhythm by beta-adrenergic antagonists or pinealectomy has not yet been extensively studied in man. Melatonin administration, always (to date), in pharmacological amounts has hypnotic effects in man and may, in some individuals modify the rhythmic characteristics of its own secretion. It remains to be seen whether, in physiological amounts, it is causally related to aspects of human sleep and other circadian or seasonal rhythms.
PubMed ID
3462328 View in PubMed
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Asymmetry of retinitis pigmentosa-related to initial optic disc vasculitis.

https://arctichealth.org/en/permalink/ahliterature51221
Source
Acta Ophthalmol (Copenh). 1992 Aug;70(4):543-8
Publication Type
Article
Date
Aug-1992
Author
L. Laatikainen
E. Mustonen
Author Affiliation
Department of Ophthalmology, University of Oulu, Finland.
Source
Acta Ophthalmol (Copenh). 1992 Aug;70(4):543-8
Date
Aug-1992
Language
English
Publication Type
Article
Keywords
Adult
Dark Adaptation
Electroretinography
Female
Fluorescein Angiography
Fundus Oculi
Humans
Optic Disk - blood supply
Retinitis Pigmentosa - pathology - physiopathology
Vasculitis - pathology - physiopathology
Abstract
A case of highly asymmetric retinitis pigmentosa is reported. Signs of pigmentary retinopathy appeared in the first eye following optic disc vasculitis or neuroretinitis of unknown etiology. Within 2 years the visual field became markedly restricted and the dark adaptation thresholds elevated. Twelve years later this eye was almost blind and the ERG was non-recordable. In the fellow eye, the first pigmentary changes were observed 5 years after the initial presentation, and the progression was slow. Nineteen years after the initial examination the visual field of the less affected eye was constricted to 30 degrees nasally and 60 degrees temporally, the dark adaptation threshold was only slightly elevated, and the full-field ERG was within normal range. It is possible that neuroretinitis or vasculitis of the optic disc caused the earlier onset and the more progressive course of pigmentary retinopathy in the initially affected eye.
PubMed ID
1414303 View in PubMed
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Autosomal dominant retinitis pigmentosa in Norway: a 20-year clinical follow-up study with molecular genetic analysis. Two novel rhodopsin mutations: 1003delG and I179F.

https://arctichealth.org/en/permalink/ahliterature163673
Source
Acta Ophthalmol Scand. 2007 May;85(3):287-97
Publication Type
Article
Date
May-2007
Author
Jan Grøndahl
Ruth Riise
Arvid Heiberg
Trond Leren
Terje Christoffersen
Ragnheidur Bragadottir
Author Affiliation
Department of Medical Genetics, University Hospital, Rikshospitalet, Oslo, Norway.
Source
Acta Ophthalmol Scand. 2007 May;85(3):287-97
Date
May-2007
Language
English
Publication Type
Article
Keywords
Adolescent
Adult
Aged
DNA Mutational Analysis
Dark Adaptation
Electroretinography
Eye Proteins - genetics
Female
Follow-Up Studies
Frameshift Mutation
Genes, Dominant
Humans
IMP Dehydrogenase - genetics
Intermediate Filament Proteins - genetics
Male
Membrane Glycoproteins - genetics
Middle Aged
Mutation, Missense
Nerve Tissue Proteins - genetics
Norway - epidemiology
Pedigree
Peripherins
Phenotype
Photography
Polymerase Chain Reaction
Retinitis Pigmentosa - diagnosis - epidemiology - genetics
Rhodopsin - genetics
Visual Fields
Abstract
To examine the clinical picture and molecular genetics of 12 Norwegian families with autosomal dominant retinitis pigmentosa (adRP) in order to achieve a genotype-phenotype correlation.
In addition to a clinical ophthalmological examination, fundus photography, dark adaptometry and electroretinography were performed. Four genes were analysed: rhodopsin (RHO); retinitis pigmentosa 1 (RP1); retinal degeneration slow/peripherin (RDS/peripherin), and inosine monophosphate dehydrogenase 1 (IMPDH1). Seven of the families had been examined about 20 years previously. A total of 63 patients or first-degree relatives (aged 18-79 years) were examined.
Mutations were found only in the RHO gene. Seven families were given a diagnosis of classical RP. Two of them had novel mutation 1003delG, and one family had the mutation V345M. Four families had pericentral retinal dystrophy (PRD), two families with the mutation A164V and one with novel mutation I179F. One family was given a diagnosis of central and pericentral retinal dystrophy (CPRD), a special type of cone/rod dystrophy, and no mutation was found.
Six of 12 families had an RHO mutation. The mutation V345M and the novel mutation 1003delG both caused classical RP, the former indicating the most unfavourable prognosis. Two of the families with PRD had the A164V mutation with a favourable prognosis, whereas the novel mutation I179F caused PRD with extremely variable expressivity.
PubMed ID
17488458 View in PubMed
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96 records – page 1 of 10.