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PubMed2001

Comparison of the effects of infant handling, isolation, and nonhandling on acoustic startle, prepulse inhibition, locomotion, and HPA activity in the adult rat.

This study examined whether early isolation (EI), early handling (EH), or early nonhandling (NH) in infant rats alters (a) prepulse inhibition (PPI) of the acoustic startle response (ASR) or its disruption by apomorphine, (b) motor activity or its stimulation by amphetamine, or (c) corticosterone activity (because of its modulation of dopamine activity), in adulthood and in comparison with a normal-husbandry postnatal control environment. EI did not affect PPI, reduced PPI disruption by apomorphine in males, and increased amphetamine-stimulated activity in males. NH increased the ASR, reduced activity in the open field, and increased corticosterone reactivity in males. In all paradigms, the effects of EH were similar to those of the control environment. This study provides an important contribution to the evidence on the relationship between postnatal experience and long-term neurobehavioral development in the rat and the relevance of this approach to animal models of neuropsychiatric disorder.

Age Factors↗

PubMed1987

A regenerable carbon dioxide removal and oxygen recovery system for the Japanese Experiment Module.

The Japanese Space Station Program is now under Phase B study by the National Space Development Agency of Japan in participation with the U.S. Space Station Program. A Japanese Space Station participation will be a dedicated pressurized module to be attached to the U.S. Space Station, and is called Japanese Experiment Module (JEM). Astronaut scientists will conduct various experimental operations there. Thus an environment control and life support system is required. Regenerable carbon dioxide removal and collection technique as well as oxygen recovery technique has been studied and investigated for several years. A regenerable carbon dioxide removal subsystem using steam desorbed solid amine and an oxygen recovery subsystem using Sabatier methane cracking have a good possibility for the application to the Japanese Experiment Module. Basic performance characteristics of the carbon dioxide removal and oxygen recovery subsystem are presented according to the results of a fundamental performance test program. The trace contaminant removal process is also investigated and discussed. The solvent recovery plant for the regeneration of various industrial solvents, such as hydrocarbons, alcohols and so on, utilizes the multi-bed solvent adsorption and steam desorption process, which is very similar to the carbon dioxide removal subsystem. Therefore, to develop essential components including adsorption tank (bed), condenser. process controller and energy saving system, the technology obtained from the experience to construct solvent recovery plant can be easily and effectively applicable to the carbon dioxide removal subsystem. The energy saving efficiency is evaluated for blower power reduction, steam reduction and waste heat utilization technique. According to the above background, the entire environment control and life support system for the Japanese Experiment Module including the carbon dioxide removal and oxygen recovery subsystem is evaluated and proposed.

Adsorption↗

PubMed2005

Gene loci in maize influencing susceptibility to chilling dependent photoinhibition of photosynthesis.

Variation in tolerance in chilling-dependent photoinhibition has been associated with a wide range of traits in comparative physiological studies. A sweet corn (Zea mays L.) population of 214 F(2:3 )families previously mapped to near-saturation with 93 RFLP DNA markers were subjected to low temperature and high-light events prior to measurement of the maximum dark-adapted quantum efficiency of PS II (F(v)/F(m)), to identify loci associated with variation in chilling-dependent photoinhibition. In the first assay with ten families varying in seedling growth and germination, significant differences were observed among families in their response to and recovery from exposure to high light at low temperature. All the 214 F(2:3) families from this population were then evaluated for tolerance of chilling-dependent photoinhibition in a controlled environment and then in three replicated trials in the field, each following naturally occurring chilling events during spring. The measured effects on F(v)/F(m) were analyzed with software that mapped segregating loci that regulate trait expression and linked to genetic markers (PLABQTL). QTL 3.096 (i.e. 96 cM on chromosome three) was consistently identified in both controlled environment and in the mean of the three field trails. Another QTL at 8.025, described the greatest percentage of total phenotypic variance (ca. 10%) for the mean reduction in F(v)/F(m) of all three periods of measurement in the field. A third QTL (4.136) showed a highly significant association in the third field trial. These three QTLs were closely associated with genes that have been mechanistically related to photoinhibition tolerance and repair. The results suggest that the ratio of F(v)/F(m) is an approach that may be used in establishing marker-assisted breeding for improved tolerance to chilling of maize in the light and in turn better early-season growth in cool temperate climates.

Cold Temperature↗

PubMed2004

Yield response to water deficit in an upland rice mapping population: associations among traits and genetic markers.

A population of recombinant inbred rice lines from a cross between the upland japonica cultivar Azucena and the upland indica cultivar Bala was evaluated in a series of upland field experiments. Water stress was imposed during the reproductive stage by managed irrigation during the dry season, while control treatments were maintained in aerobic, well-irrigated conditions. Water deficit resulted in a yield reduction of 17 to 50%. The genetic correlation between stress and control yields was quite high when stress was mild, and the heritability of yield was similar in stress and control treatments across both years of this study. Genetic correlations between secondary traits such as leaf rolling and drying and yield under stress varied from high (leaf drying) to insignificant (leaf rolling). Lines with superior yield tended to have fewer panicles and larger grain size than the high-yielding parent, Bala, even though the panicle number was positively correlated with yield and the thousand-grain weight was not associated with yield for the population as a whole. Analysis of quantitative trait loci (QTLs) for yield and yield components allowed the identification of 31 regions associated with growth or yield components. Superior alleles came from either parent. Several of the regions identified had also been reported for root mass at depth or maximum root length in this population in other studies made under controlled environments, and for leaf drying (LD) in field studies. However, the direction of the effect of QTLs was not consistent, which indicates that there was not necessarily a causal relationship between these secondary traits and performance. We conclude that mapping populations can provide novel insights on the actual relationships between yield components and secondary traits in stress and control environments and can allow identification of significant QTLs for yield components under drought stress.

Biomass↗

PubMed1990

Regulation of photosynthate partitioning into starch in soybean leaves : response to natural daylight.

Studies conducted in controlled environments indicate that daylength affects the proportion of photosynthate stored in leaves as starch or sucrose. To examine the response of partitioning to natural daylight, soybeans (Glycine max [L.] Merr. cv Williams) were grown at 12 different times between May and November in a constant temperature greenhouse without supplemental lighting. Plants were transferred from the greenhouse to a controlled environment chamber at the end of civil twilight at a set developmental stage (expanding seventh trifoliolate leaf, counting acropetally). Net photosynthesis and the accumulation of starch and sugar in fully expanded fourth trifoliolate leaves were determined the following day under standard conditions in the chamber (lights-on synchronized with sunrise). Photosynthesis on a leaf area basis decreased about 10% between midsummer and early autumn. Leaf soluble sugar accumulation was low at all harvests. However, a twofold increase in photosynthate partitioning into starch occurred over the same time period, resulting in an 80% increase in absolute starch accumulation rate. Starch was responsible for about 78% of the increase in leaf dry matter during the light at all harvests, indicating that starch accumulation as affected by prior daylight conditions will alter export of photosynthate during the light period. Photosynthate partitioning into starch was linearly correlated with daylength at harvest, prior average peak solar irradiance, and other parameters that correlated with daylength and solar radiation such as harvested top dry matter. The relation between growth and seasonal changes in daylight (including daylength, irradiance, and light integral) are discussed in relation to photosynthate partitioning under field conditions.

Journal Article↗

PubMed1999

The efficacy and safety of argon plasma coagulation therapy in Barrett's esophagus.

BACKGROUND: Thermoablation is being used to eliminate the metaplastic epithelium of Barrett's esophagus and allow its reversal into squamous epithelium in an acid-controlled environment. This study assessed the efficacy and safety of a new thermoablation technique, argon plasma coagulation. METHODS: Patients with circumferential Barrett's esophagus 2 to 5 cm long were enrolled. Acid suppression was accomplished with lansoprazole. One-half the circumference of Barrett's mucosa was treated with argon plasma coagulation, and the other half served as an internal control. After macroscopic squamous re-epithelialization occurred, biopsy specimens were obtained from both areas systematically. RESULTS: Nine patients, all men with a mean age of 51.1 years, completed the study. During 24-hour esophageal pH monitoring a pH less than 4 occurred on average 2.8% of the time with a mean dose of lansoprazole of 70 mg/day. Squamous re-epithelialization developed in treated areas in all 9 patients. Biopsy showed that 7 of 9 patients (77.8%) had squamous re-epithelialization without intestinal metaplasia. Biopsy showed that 2 of 9 patients (22.2%) had squamous re-epithelialization with evidence of underlying intestinal metaplasia. There were no serious complications. CONCLUSIONS: Argon plasma coagulation in an acid-controlled environment was both efficacious and safe in the treatment of Barrett's esophagus. However, the reappearance of squamous epithelium after therapy did not exclude the presence of underlying intestinal metaplasia.

2-Pyridinylmethylsulfinylbenzimidazoles↗

PubMed2001

Creating a peaceful school learning environment: a controlled study of an elementary school intervention to reduce violence.

OBJECTIVE: The impact of a manual-based antiviolence program on the learning climate in an elementary school over 4 years was compared with the outcome in a control school. METHOD: The two schools were matched for demographic characteristics. The intervention in the experimental school was based on zero tolerance for bullying; the control school received only regular psychiatric consultation. Disciplinary and academic achievement data were collected in both schools. RESULTS: The experimental school showed significant reductions in discipline referrals and increases in scores on standardized academic achievement measures. CONCLUSIONS: A low-cost antiviolence intervention that does not focus on individual pathology or interfere with the educational process may improve the learning environment in elementary schools.

Achievement↗

PubMed2003

QTL analysis for ascochyta blight resistance in an intraspecific population of chickpea (Cicer arietinum L.).

In both controlled environment and the field, six QTLs for ascochyta blight resistance were identified in three regions of the genome of an intraspecific population of chickpea using the IDS and AUDPC disease scoring systems. One QTL-region was detected from both environments, whereas the other two regions were detected from each environment. All the QTL-regions were significantly associated with ascochyta blight resistance using either of the disease scoring systems. The QTLs were verified by multiple interval mapping, and a two-QTL genetic model with considerable epistasis was established for both environments. The major QTLs generally showed additive gene action, as well as dominance inter-locus interaction in the multiple genetic model. All the QTLs were mapped near a RGA marker. The major QTLs were located on LG III, which was mapped with five different types of RGA markers. A CLRR-RGA marker and a STMS marker flanked QTL 6 for controlled environment resistance at 0.06 and 0.04 cM, respectively. Other STMS markers flanked QTL 1 for field resistance at a 5.6 cM interval. After validation, these flanking markers may be used in marker-assisted selection to breed for elite chickpea cultivars with durable resistance to ascochyta blight. The tight linkage of RGA markers to the major QTL on LG III will allow map-based cloning of the underlying resistance genes.

Alleles↗

PubMed2004

Effect of temperature on the survival and infectivity of Pseudotheraptus devastans vector.

The aim of this study was to investigate under a controlled environment, the effect of temperature on the survival and infectivity of Pseudotheraptus devastans Distant, a cassava anthracnose disease vector. The insect P. devastans was collected from young cassava (Manihot esculenta Crantz) field plots, at the International Institute of Tropical Agriculture, (IITA), Ibadan, Nigeria. A mixture of the different developmental stages of eggs, first to fifth instar nymphs, and adults, were incubated in controlled environment chambers, under various constant temperatures of: 15, 17, 22, 25, 27, 30, and 35 degrees C. Relative humidity at different temperature conditions were recorded and maintained at 90%, 85%, 80%, 75%, 70%, 65%, and 60%, respectively. A significant increase in insect survival was observed between 22 and 27 degrees C temperature conditions while a significant decrease in survival was observed at 15 degrees C and above 30 degrees C. Lesion number, lesion diameter and infectivity among the insect stages varied as a function of temperature and relative humidity. Infectivity was highest at 22-25 degrees C maintained at 75-80% RH and lowest at 15 degrees C and above 30 degrees C maintained respectively, at 65% RH and 90% RH. There was considerable low vector infectivity due to low survival of the insects at extreme temperatures.

Animals↗

PubMed2000

Diurnal variations in the mood and performance of highly practised young women living under strictly controlled conditions.

The diurnal variation in a range of psychological functions and core body temperature were investigated in a series of studies involving a total of 24 highly practised young women who lived in a controlled environment and on a strictly regimented 24-hour routine for 6 or 7 days. Ten participants were exposed to the natural light/dark cycle (L/Dc) through windows, whereas the 14 remaining participants saw no daylight, but all had access to normal clock time. A battery of mood and performance tests was completed every 2 hours whilst awake (08:00-00:00), resulting in nine equally spaced measures per waking day. Average time of day (ToD) functions were calculated from the last 5 or 6 days spent in the controlled environment. Significant ToD effects were found for many of the variables taken although the nature of these effects differed across measures, with a 'post-lunch dip' being observed at 16:00 in some variables. Analysis of the standardized data established that all variables presented reliably different ToD functions to core body temperature, whilst factor analyses indicated possible relationships between the variables. It was concluded that those variables that exhibited diurnal variation showed trends that did not parallel those in core body temperature.

Adult↗

PubMed2005

Temperature stress can alter the photosynthetic efficiency and secondary metabolite concentrations in St. John's wort.

Temperature stress is known to cause many physiological, biochemical and molecular changes in plant metabolism and possibly alter the secondary metabolite production in plants. The hypothesis of the current study was that temperature stress can increase the secondary metabolite concentrations in St. John's wort. Plants were grown under controlled environments with artificial light using cool white fluorescent lamps and CO2 enrichment and 70-day-old plants were subjected for 15 days to different temperature treatments of 15, 20, 25, 30 and 35 degrees C before harvested. Major aim of the study was to increase the major secondary metabolites in St. John's wort by applying temperature stress and to evaluate the physiological status of the plant especially the photosynthetic efficiency and peroxidase activity of the leaf tissues exposed to different temperatures under precisely controlled environmental factors. Results revealed that relatively high (35 degrees C) or low (15 degrees C) temperatures reduced the photosynthetic efficiency of the leaves of St. John's wort plants and resulted in low CO2 assimilation. Net photosynthetic rates and the maximal quantum efficiency of PSII photochemistry of the dark adopted leaves (phi(p)max) decreased significantly in the leaves of plants grown under 35 or 15 degrees C temperature treatments. High temperature (35 degrees C) treatment increased the leaf total peroxidase activity and also increased the hypericin, pseudohypericin and hyperforin concentrations in the shoot tissues. These results provide the first indication that temperature is an important environmental factor to optimize the secondary metabolite production in St. John's wort and controlled environment technology can allow the precise application of such specific stresses.

Hypericum↗

PubMed1987

Lighting and sex ratio for breeding ringnecked pheasants in confined housing.

In two trials with breeding pheasants, pheasants were assigned to two male:female sex ratios (1:12 and 1:18) arranged factorially with two lighting regimens (14 or 16 hr of light) in a 24-hr period. In each trial, 1644 or 1680 pheasant hens divided in two replicates were assigned to each experimental treatment and placed in controlled environment housing. Hen mortality, percent culled eggs, total eggs per hen-housed, fertility, hatchability, and usable chicks per hen-housed were determined over a 9-week production period. Although mortality and percent hatch were not affected by either sex ratio or lighting, percent culled eggs increased with increased light (16 hr light) and usable chicks per hen-housed decreased with increased light. Increasing the sex ratio from 1:12 to 1:18 increased egg production but decreased fertility. These data demonstrate that pheasants reared in a controlled environment require less than 16 hr light for maximizing usable chick production per hen-housed and there is a trade-off between fertility and egg production.

Animals↗

PubMed1968

Leaf diffusion resistance, illuminance, and transpiration.

Stepwise increases in fluorescent illuminance, imposed as a single variable in a controlled environment, induced progressive stomatal opening in 8 plant species, as evidenced by a consistent decrease in leaf diffusion resistance (R(L)), ranging from 15 to 70 sec cm(-1) in darkness to about 1 sec cm(-1) at approximately 40 kilolux. The minimum R(L) values were the same for the upper and the lower epidermis, provided that stomatal density was adequate. Saturation illuminance was not achieved in any species; extrapolation indicates that 50 kilolux would bring about full stomatal opening (R(L) </= 0.1 sec cm(-1)).In 4 species, reasonable agreement was obtained in a controlled environment between transpiration as measured by weight loss and that calculated from determination of (a) the difference in water vapor density from leaf to air, (b) the boundary layer resistance, and (c) the leaf diffusion resistance. This result confirms the physical validity of the resistance measurement procedure.

Journal Article↗

PubMed1985

Comparison of EMT blood pressure measurements with an automated blood pressure monitor: on scene, during transport, and in the emergency department.

Auscultation or palpation of blood pressure in critically ill patients by emergency medical technicians (EMTs) can be difficult, if not impossible, because of ambient noise, motion artifact, limited access to patients, or weak pulses. Automated blood pressure monitors (ABPMs) have been designed to overcome these problems during field emergencies and patient transport. Our study compared blood pressure measurements taken by EMTs with measurements provided by a Lifestat ABPM. Measurements in emergency patients on scene, during transport, in the emergency department (ED), and in a controlled environment were compared. Measurements in the various sites were obtained from 57 patients, and provision was made for two measurements at each site. Comparison of on-scene systolic blood pressures yielded a mean absolute systolic difference of 10.46 +/- 1.42 mm Hg and a mean absolute diastolic difference of 9.33 +/- 1.32 mm Hg. During transport systolic pressures showed a mean absolute difference of 11.50 +/- 1.72 mm Hg, and diastolic pressures showed a mean absolute difference of 7.59 +/- 1.16 mm Hg. Mean absolute differences in the ED were 11.23 +/- 1.49 mm Hg systolic and 8.37 +/- 1.25 mm Hg diastolic. Ninety comparison measurements in a controlled environment yielded a mean absolute systolic difference of 8.74 +/- 0.87 mm Hg and a mean absolute diastolic difference of 7.97 +/- 0.72 mm Hg. Comparison of mean diastolic pressure differences between EMT and ABPM measurements in various settings revealed some small, but statistically significant, discrepancies that were not considered clinically relevant.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Pressure↗

PubMed2005

The epidemiology and prevention of suicide by hanging: a systematic review.

BACKGROUND: Hanging is one of the most commonly used methods for suicide worldwide. In England and a number of other countries, its incidence has increased over the last 30 years. This review summarizes the published literature on suicide by hanging. The focus is on its epidemiology in England and on identifying potential means of prevention. METHODS: We searched Medline (1966-2003), Embase (1980-2003), CINAHL (1982-2003) and PsycINFO (1967-2003). As considerable research on suicides occurring in prisons and psychiatric hospitals in England and Wales has been carried out by the National Confidential Inquiry into Suicide and Homicide (Manchester) and the Prison Service's Safer Custody Group, we obtained additional information from these sources. RESULTS: Only a small proportion (around 10%) of hanging suicides occur in the controlled environments of hospitals, prisons, and police custody; the remainder occur in the community. The most commonly used ligatures (rope, belts, flex) and ligature points (beams, banisters, hooks, door knobs, and trees) are widely available; thus prevention strategies focused around restriction of access to means of hanging are of limited value. Around 50% of hanging suicides are not fully suspended--ligature points below head level are commonly used. Case fatality following attempted suicide by hanging is around 70%; the majority (80-90%) of those who reach hospital alive survive. CONCLUSION: Strategies to reduce suicide by hanging should focus on the prevention of suicide in controlled environments, the emergency management of 'near-hanging' and on the primary prevention of suicide in general. More research is required to better understand the recent rise in popularity of this method.

Adolescent↗

PubMed1999

Alveolar clearance in horses with chronic obstructive pulmonary disease.

OBJECTIVE: To assess sensitivity of scintigraphic alveolar clearance rate as an indicator of alveolar epithelium damage in horses. ANIMALS: 5 healthy horses (group A) and 5 with chronic obstructive pulmonary disease (COPD; group B). PROCEDURE: Horses underwent clearance rate (k [%/min]) determination. Clearance rate of group-B horses was determined after remission of the disease following 2 months at pasture (remission 1), stabling in a controlled environment (remission 2), and during crisis induced by exposure to moldy hay and straw. Methacholine challenge test was performed at each investigation period to determine nonspecific pulmonary airway hyperresponsiveness. Pulmonary function tests (PFT) also were performed, and cell populations in bronchoalveolar lavage (BAL) fluid were determined on another occasion. RESULTS: Group-B horses had significantly faster mean clearance rate during crisis (k = 4.30+/-0.95%/min), compared with that for remission 1(k = 1.98+/-0.55%/min), which did not differ from the rate in group-A horses (k = 1.95+/-0.33%/min). Despite lack of clinical signs of COPD during remission when stabled in a controlled environment, an intermediate value was found (k = 3.20+/-0.72%/min). CONCLUSIONS: This technique allowed grading of lung damage induced by COPD, whereas use of PFT and determination of BAL fluid cell populations failed to differentiate between remission 1 and remission 2. CLINICAL RELEVANCE: Determination of alveolar clearance rate by use of scintigraphy is a sensitive indicator of lung damage. A modified clearance rate was found despite the lack of clinical and functional changes.

Animals↗

PubMed1978

Behavior therapy for a child with Lesch-Nyhan syndrome.

The behavioural symptoms in a 10-year-old boy with Lesch-Nyhan syndrome were effectively ameliorated by the behavior therapy techniques of systematic desensitization and extinction. Therapy was undertaken in a highly controlled environment. The hypothesis that the self-destructive behaviours in this syndrome were voluntary and maintained through continuous reinforcement was confirmed. Characteristic biting and other maladaptive behaviours were extinguished. Over a period of time it was possible to remove all the physical restraints previously used to prevent the boy injuring himself. During treatment his anxiety, associated with phobic reaction to being unrestrained, was reduced by nitrous oxide. At 1 1/2 years follow-up the boy continues to be symptom-free. He attends a special class at school and is learning to walk with crutches. It is emphasied that a trained and experienced therapist and a controlled environment are essential for the success of this form of behaviour therapy, and the dangers inherent in this method of treatment are discussed.

Anxiety↗

PubMed1984

Recognition specificities, development and possible biological function of natural killer cells in the mouse. II. Changes in NK recognition during ontogeny and ageing, and examination of role of environment in controlling the expressed recognition repertoire.

We have used a spleen fragment assay to assess subpopulations of NK effector cells in individual mice and to analyse the patterns of inhibition of lytic activity seen in the presence of different sugars (mono-, di- and tri-saccharides). Our data suggest that during ontogeny the heterogeneity (diversity) of the NK effector population increases in a fashion which is somewhat characteristic of the individual strain under investigation. Furthermore, when a similar analysis was performed on NK cells in the spleen of lethally irradiated recipient mice receiving syngeneic or semi-allogeneic bone marrow stem cell precursors, we found that the phenotype of inhibition by different sugars was a characteristic of the bone marrow donor and not of the recipient. In so far as the assay described assesses target recognition by NK cells (and not subsequent parameters involved in the lytic event) these data can be interpreted in terms of a relative independence of the expressed recognition repertoire of NK cells from the environment in which their differentiation occurs.

Aging↗