Open Sunlight Research Articles

Occupational Stress Perception and Healthy Lifestyle in Railroad Workers

A survey was performed in 2008 on a representative stratified sample of 245 railroad employees in Slovenia (168 blue-collar and 77 white-collar workers) with the aim of exploring different dimensions of workers’ lifestyle health. For this purpose a special questionnaire was developed. The intensity of perceived job stress was measured with one general index based on a 4-point ordinal scale. There were 54.3% of employees who perceived their work as stressful or very stressful. No significant differences between blue- and white-collar workers were found. Twenty-six dimensions of lifestyle were measured. There were 66.9% of interviewed employees who were found to be overweight or obese (BMI 25 or higher). Differences in lifestyle between blue- and white-collar workers were not significant at the level of 0.05, except for some dimensions: blue-collar workers spend more time in the open air and sunlight and consume lunch as the main meal more regularly. In general, lifestyle was not confirmed as statistically significant (at 0.05 level) moderator of perceived job stress, explaining just 11% of variance. However, there are some dimensions that are significantly (P

Global Warming/green House Effect

Environment is the sum of all social, physical, chemical, biological or economical factors which constitute the surroundings of man to both his creator and moulders of environment. This paper discusses on global warming and green house effect and suggests the way to control global warming and the steps to be taken to reduce the temperature of the earth. The produced CO 2 from industries and from several other sources is to be sent through separate pipe lines to glass chambers kept in open atmosphere and sunlight is to be supplied to it. When chlorophyll pigments are supplied through plant sources or through algae that survive in anaerobic conditions to the glass chamber, the incoming CO 2 will get converted into oxygen due to photosynthesis. The outgoing oxygen can be collected through outlets and can be used in hospitals and several other places. In this way we can control the level of CO 2 in atmosphere and thus reducing global warming.

Soil microfungi of Nahal Meitsar, “Evolution Canyon” IV, Golan Heights

In the present study, species composition, diversity characteristics (species richness, heterogeneity, evenness), and dominant species of soil microfungal communities in Nahal Meitsar, southeastern Golan Heights, Israel, were examined. Seventy species belonging to Zygomycota (3), teleomorphic Ascomycota (6), and anamorphic Ascomycota (61) were isolated. Mesophilic Penicillium species dominated the microfungal communities in all localities studied: P. lanosum in shade under trees and in open sunlight on the “European” north-facing slope (NFS) and P. aurantiogriseum in sunlight on the “African” south-facing slope (SFS). The SFS, in contrast to such slopes in “Evolution Canyons” I and II (Nahal Oren, Mount Carmel, and Nahal Keziv, Upper Galilee, Israel), had poor species composition and lower biodiversity characteristics than the NFS. Such simplification of the SFS soil microfungal community may have been the result of pasturage on this slope, followed by soil degradation and development, of monotonous weed vegetation.

Potential for Anopheles campestris (Diptera: Culicidae) to transmit malaria parasites in Pa Rai subdistrict (Aranyaprathet, Sa Kaeo Province), Thailand.

Member(s) of the Anopheles barbirostris group Reid, particularly Anopheles barbirostris and Anopheles campestris Reid are the suspected vectors of Plasmodium vivax in Pa Rai (Aranyaprathet, Sa Kaeo province). To determine if An. barbirostris, An. campestris, or both, are present in Pa Rai and to determine their potential to transmit malaria, a field and laboratory study was conducted. Isofemale colonizations of wild caught mosquitoes captured by landing catches were made for species confirmation and to determine the mosquito life cycle. Pupal morphology indicated all mosquitoes were An. campestris. During the late rainy season (October and November), An. campestris populations comprised 78.6% of all females captured by human landing catches and 7.1% of mosquitoes in a cow-baited trap. The biting activity cycle peaked between 2000 and 0100 hours and was highest (17.6 bites per person per hour) at 2300 hours. More An. campestris bit people indoors (nine bites per person per hour) than outdoors (four bites per person per hour). Immature An. campestris were found in ponds, swamps, rice-fields, puddles, marshes, ground pools, and pits with open sunlight to partial shade. The time from egg hatch to adult was 18-47 d and 14-22 d under laboratory (25.0-27.0 degrees C) and ambient (26-32 degrees C) conditions, respectively. The fecundity of An. campestris ranged from 173 to 311 eggs. Based on experimental infections, An. campestris was able to support the sporogonic cycle of P. vivax with 76.2 and 23.8% oocyst and sporozoite formation rate, respectively. An. campestris shows high potential as a malaria vector in Pa Rai.

Physiological Ecology of Native and Alien Dry Forest Shrubs in Hawaii

Hawaii's dry forests are among the most endangered of all ecosystems in the archipelago. Invasion of alien plant species into these ecosystems is one of the most significant threats to on-going efforts to preserve and restore Hawaii's remaining dry forests. Comparing the physiological performance of alien and native species can offer causal explanations behind the relative success of alien plant invasions within Hawaiian dry forests and elsewhere. We compared maximum rates of net CO2 assimilation, water-use efficiency (WUE), daily carbon gain, and leaf morphology for three native and two alien shrubby species growing within 1-m2 plots under two natural light (sub-canopy shade relative to open full sunlight) treatments. Maximum rates of net CO2 assimilation were similar between alien and native species (8.15 vs. 7.12 μmol m−2 s−1, respectively), however, native plants exhibited lower stomatal conductance and higher instantaneous WUE than alien plants in all treatments (0.13 mol m−2 s−1 and 72.36 μmol CO2 mol H2O−1 against 0.23 and 58.78, respectively). Alien plants had approximately 65% more aboveground biomass than native plants. This result may reflect differential seed production and seed bank viability between native and alien species. We found an overall strong, positive correlation between species-specific physiological traits and final species aboveground biomass. Based on this type of information we can predict species-specific boundaries across light gradients, and focus restoration efforts accordingly.

INFLUENCE OF LIGHT AND PHOTOSYNTHESIS ON ALKALOID CONCENTRATION IN LARKSPUR

Concentrations of toxic norditerpenoid alkaloids vary greatly in tall larkspur (Delphinium barbeyi) and may be influenced by environmental stress. We evaluated the effect of shade, darkness, and inhibition of photosynthesis on toxic alkaloid concentration. In plants treated with metribuzin to inhibit photosynthesis, alkaloid concentration increased, but dry weight of the plants decreased as growth ceased, leaving absolute alkaloid content similar to that of control plants. Short-term shade (70% reduction in sunlight for three days), dark treatments from leaves collected at night, and aluminum foil covered leaves all increased alkaloid concentration in comparison to untreated control plants. It appears that absolute amounts of alkaloids remained the same, but the mass of stressed plants declined as nonstructural carbohydrates were depleted, thus increasing the relative concentration of alkaloids. We conclude that norditerpenoid alkaloids in larkspur do not respond to short-term light stress. Alkaloid concentration was lower in larkspur plants growing beneath forest canopy and in potted plants in a long-term shade study (70% reduction in sun light for 21 days) than plants growing in open sunlight. Long-term shade may have reduced synthesis of norditerpenoid alkaloids, particularly in the earlier developmental stages of the plant. Shade stress or photosynthesis inhibition apparently did not increase norditerpenoid alkaloid synthesis, which contrasts with the carbon/nutrient balance theory of plant defense.

Toxic Alkaloid Concentration in Tall Larkspur Species in the Western U.S.

Larkspur (Delphinium spp.) kills more cattle on mountain rangelands in the western U.S. than any other plant, disease or predator. The concentration of toxic alkaloids was measured in 4 larkspur species, at 10 locations, at 2-week intervals during the growing season. In addition, multi-year samples from previous studies were analyzed to determine year-to-year variation in toxic alkaloids. Mountain larkspur (D. glaucum Wats.) had the highest concentration of toxic alkaloids averaged over growth stages (1.01% of dry weight), tall, (D. barbeyi (L.) Huth) and waxy larkspur (D. glaucesens Rydb) were intermediate (0.65 and 0.49% respectively), and duncecap (D. occidentale S. Watts) was lowest (0.29%). Toxic alkaloid concentration generally declined as the plants matured. However, toxic alkaloids in tall larkspur at Yampa, Colo. increased slightly in the pod stage, and toxic alkaloids in waxy larkspur increased from the vegetative to the bud stage. Concentration of toxic alkaloids in tall and duncecap larkspur leaves were higher in plants growing in open sunlight than those shaded under aspen or conifer canopy. Toxic alkaloid concentration varied among individual plants (C.V. 20-60%). Knowledge of the toxic alkaloid concentration of larkspur populations can be used to predict the risk of larkspur poisoning.

Influence of tree cover on herbaceous above- and below-ground phytomass in the Sahelian zone of Senegal

An experimental study was undertaken on a complex ecological system in the semi-arid Sahelian region of Senegal. The effects of tree cover on the above- and below-ground phytomass of the herbaceous layer were studied. The results show that: (1) herbaceous above-ground production was 1·5 to 4 times greater under the canopy than in the open sun light; (2) understory root phytomass was about two-fold greater than the root phytomass of the open grassland; and (3) the root/shoot ratio was 2·5 higher in the open than in the shade. Increased herbaceous layer productivity was interpreted as a result of better climatic conditions and greater soil fertility within the canopy zones.By promoting the development of herbaceous vegetation, trees increase the long-term production potential of the zone and, in consequence, improve conditions for livestock husbandry.

Shading reduces exploitation of soil nitrate and phosphate by Agropyron desertorum and Artemisia tridentata from soils with patchy and uniform nutrient distributions.

Shading may both lessen the demand for soil nutrients and also the energy supply for nutrient acquisition. Since root foraging for nutrients in patchy environments can be energy-costly, especially for an immobile nutrient such as phosphate (P), the effects of shading may be most expected in heterogeneous soils. Plant acquisition of nitrate (N) and phosphate from soils with patchy and uniform nutrient distributions was determined in a field study under open sunlight and with shading for two common perennial Great Basin shrub steppe species, Agropyron desertorum and Artemisia tridentata. Partial shading in a pattern which can occur in shrub steppe vegetation significantly decreased plant N and P acquisition from soils both in the patchy and the uniform nutrient treatments. Artemisia was more affected by the shading than was Agropyron. Exploitation of the rather immobile P ion by both species was reduced to a much greater degree by the shading in the patchy distribution treatment than in the uniform nutrient treatment. As expected, plant acquisition of the more mobile N varied little with nutrient distribution treatment for both species and the depression of N acquisition by shading was the same in both nutrient distributions. The effects of shading appeared to have had its primary influence on different components of root foraging in the two species, especially in the nutrient-rich patches. For Agropyron shading primarily affected root proliferation, as indicated by reduced root density in patches. For Artemisia, shading most influenced root physiological uptake capacity and this was most pronounced in the nutrient-rich patches. While aboveground competition for light may generally reduce nutrient acquisition, the effects appear to be most pronounced if root systems of these steppe species are foraging for nutrients such as P in spatially heterogeneous soils.

POST-HARVEST DETERIORATION IN WEIGHT AND JUICE QUALITY OF CANE VARIETIES

Harvested canes of sugarcane varieties viz., CoC 85061 and CoC 671 were stalled in open sun light, under tree shade and in open sunlight covered with cane trash. Loss in cane weight and juice quality was estimated at 24 hours interval. The cane stored under tree shade and stored upto 48 hrs. recorded significantly minimum loss of cane weight and juice quality. The CoC 85061 recorded lesser loss in cane weight, sucrose content, purity and commercial cane sugar and higher gain in reducing sugar content.

A microprocessor-based semiconductor solar radiometer

The photocurrent produced by a silicon PN junction is used as a solar radiation transducer. It has high and linear sensitivity in the main part of open sunlight spectrum. Using a commerical device as sensor, a low-cost solar radiometer can be constructed. The photocurrent produced is electronically tailored to store solar radiation data in a microprocessor-based data acquisition system. This portable instrument can be used in remote sites and substitutes solar monitor, integrator and data-logger equipment. The data can be transported by a RS-232 port or in a nonvolatile static RAM card, interfaceable with personal microcomputer.

Experimental formulations ofBacillus sphaericus for the control of anopheline and culicine larvae

Four experimental formulations ofBacillus sphaericus Neide (2362 isolate) were evaluated for larvicidal activity against culicine and anopheline larvae in several natural and artificial habitats. A granular formulation (5% primary powder) was tested against natural populations of mosquitoes in two simulated habitats in Florida and in maturing and reflooded rice fields in Louisiana. Larvae ofCulex quinquefasciatus Say were reduced by 97 and 99% after application of the granules at the rate of 10 kg/ha to polluted tanks and 2.5 kg/ha to sod-lined potholes, respectively. Anopheline andPsorophora columbiae (Dyar and Knab) larvae were reduced by 68 and 92–100%, respectively, after application of 5 kg granules/ha to rice fields. A flowable concentrate (12.8% primary powder) applied to unpolluted and organically enriched habitats in Florida at 0.25 kg/ha reduced populations ofCulex spp. by 93–100% and 99%, respectively. Sustained-release briquets (5% primary powder) applied at the rate of one half briquet/1.8 m2 sod-lined potholes reduced larval populations ofCx. quinquefasciatus by 88–95% for up to 2 weeks in open sunlight. Sustained-release pellets (30% primary powder) applied to small woodland pools in Memphis, TN at the rate of four pellets/pool virtually eliminated larval populations ofCx. restuans Theobald for over 8 days. Variable persistance of larvicidal activity was noted for the other treatments depending on the formulation, target species and habitat.

Laboratory Evaluation of Two Insect Growth Regulators as Baits for German Cockroach Control, 1984

Abstract Ciba Geigy 112913 and CME 13406 were applied to Purina Dog Chow in an acetone solution at dosage rates of 0.5% and 1.0%. Two hundred grams of dog food to be used throughout the test was placed in the IGR-acetone solution until complete saturation had occurred. The dog food absorbed 39 ml of solution. The treated dog food was placed in open sunlight for 2 h, until dry. Tests were not initiated until 4 h after the dog food had been treated. CME 13406 was unsoluable in acetone. When added to acetone, a suspension was formed. This mixture was thoroughly mixed when added to the dog food. Two checks were used in the test. One consisted of treating dog food with acetone alone and the other was left untreated.

An Integrating Pyranometer for Climatological Observer Stations and Mesoscale Networks

Abstract The silicon photovoltaic solar cell has made possible the construction of simple pyranometers of reasonable accuracy. Cell response is linear, temperature sensitivity is low, and spectral response does not cause serious error, provided the cell is used in open sunlight. The solar cell has been mounted beneath a special diffusing unit to obtain a rugged pyranometer with excellent cosine response. This pyranometer has been coupled with a solid state integrator developed for this purpose. The integral is recorded with either visual or printing counters. Tests were made during September 1965 through February 1966 when low solar altitude and severe operating conditions would cause greatest error; and again during March 1966 through July 1966 when solar radiation intensities were high. For the first period the standard error of estimate and the solar radiation means were, respectively, 84 and 2200 Wh m−2 day−1. For the second period the corresponding values were 158 and 5630 Wh m−2 day−1.

Effect of environmental temperature on diurnal variation of blood constituents in the bovine.

Five yearling Hereford steers were maintained in the open sunlight for three sampling periods; each period separated by 7 days. Feed was withheld during the sampling periods and water was restricted throughout the second sampling period. Whereas total serum protein varied directly in a linear fashion, blood creatinine, plasma cholesterol and carotene showed an inverse relationship with environmental temperature. A consistent relationship existed between time of sampling and plasma carotene concentration. Statistical analyses failed to show a consistent relationship between sampling time or temperature and levels of uric acid and glucose.

On the use of a modified fifteen-minute hematoxylin and eosin tissue stain

A RAPID, simple, uniformly successful staining method is certainly desirable. Where large numbers of slides must be made-for example, in the case of student loan collections, for large biopsy services, or in the case of laboratories that employ but a single technician-the time spent in staining slides is an important factor. We have tried several rapid staining methods and have found that a modification of a method introduced by Ziegler1 has produced outstanding results. A wide variety of tissues were stained with quite uniform success. There is good contrast betweeri the bluish purple shades and the pink counterstain. No difference in fastness was observed when compared with other hematoxylin and eosin techniques, and there appeared to be no difference in fading when comparable sections were placed on a window ledge in open sunlight for about four months. Best results were obtained when a 10 per cent formalin solution was used a,s a fixative. Zenker’s fixative gives slightly less impressive staining, but this may be overcome by staining in the hematoxylin for two or three more minutes. Acid fixatives do not give good results unless the tissue is washed most thoroughly before embedding. Modified Technique

Bryophytes of the Jornada Experimental Range, New Mexico

A small collection of bryophytes was made on the Jornada Experimental Range in southern New Mexico by the writer as a spare-time study in 1934 and 1935. The number of species represented, about 25, is considerably less than that of Brother Arsene's' collections in the higher mountain zones of northern New Mexico. Twelve of these species, indicated by an asterisk in the list below, were not cited by Brother Arsene. Inasmuch as differences in bryophyte flora are largely the result of differences in environmental conditions, the physiography and climate of the Jornada Experimental Range will be reviewed briefly. This range, with an area of 302 square miles, is north of Las Cruces, Dona Ana County, and is located in one of the sections of least rainfall of the State. For the most part it is a plain which varies in elevation from 4,000 to 4,600 feet. It is a part of the Lower Sonoran Life Zone, with unconsolidated sands, adobe, and gravel and without springs and streams. On the east border, San Andres Mountains and foothills, composed chiefly of upper Paleozoic limestone with some sandstone and shale, rise to a maximum elevation of 8,ooo feet in the Upper Sonoran Life Zone. The average annual rainfall is 8.97 inches on the plain at the range headquarters, elevation 4,150 feet, and 12.6I inches in the foothills at Ropes Spring, elevation 5,600 feet. Collections were made also in Dona Ana Mountains of igneous rock at the southwestern edge of the area. The vegetation of this section, mainly semidesertshrub and grassland types, has been described by Campbell2 and others. Bryophytes, which are dependent upon water for fertilization, naturally are rare in this region where water is scarce. On the plain they occur in the shade of shrubs and grasses, rarely in the open sunlight. Most of them are confined to the mountains and foothills, where rock crevices and ledges furnish shade and retain moisture longer than elsewhere in this region. Several springs in the mountains have representatives of a few species of mosses around them. More species are represented on the top of the east side of San Andres Peak, elevation 8,ooo feet, than on the west slope. Trees and logs are too scarce and too exposed to serve as habitats but members of the species Orthotrichum diaphanum were found on a

The Distribution and Adaptation of Poa Bulbosa in the United States and in Foreign Countries1

Original observations on P. bulbosa, chiefly var. vivipara, in the United States, supplemented by data in the European literature and from a few unpublished sources, indicate a wide distribution for this grass. It is found on a large number of soil types, including rocky, gravelly, sandy, clay, adobe, limestone, alkali, and glacial formations. It is found in semi-desert regions and in forest areas; on dry, drained lands and on overflow lands, and in snow-covered regions; in open sunlight and in dense shade; along roadsides; on infertile, virtually bare land, and in cultivated fields; and at elevations from sea-level to above 10,000 feet. This grass is distributed over wide areas of the earth's surface. Quite often the growth and stands during the first year after planting are small and spotted. The dual multiplication method of P. bulbosa makes possible a fairly rapid increase of plants. Thin stands on land adapted to its growth will usually, within 3 or 4 years, thicken very materially and, if other conditions are favorable, full stands result. From the agricultural standpoint, P. bulbosa is at present most widely used and of most farm value in the United States in southern Oregon and northern California, where it is becoming well established in some sections and is frequently dominant under the conditions to which it is especially adapted.

Bacterial Destruction through Glass

INVESTIGATORS have recently emphasized the very obvious fact that ultraviolet stimulation of the skin or tissues of a patient, or other room occupant, occurs only when the light rays actually reach the individual; and that, as might be expected, such stimulation varies directly with the amount of light received, depending upon the individual's nearness to the window and whether the window contains ordinary window glass or glass which is to ultraviolet light. The same limitations exist with regard to bacterial destruction by light, of course; but since air circulates throughout a room, any agent which kills the bacteria in any part of it must affect the bacterial content of the room as a whole. From this point of view, there would, therefore, be a real advantage in replacing ordinary window glass with glass which is more to ultraviolet rays; and two different types of experiments were undertaken to determine the relative bacterial destruction which may be obtained with (1) unobstructed or open sunlight, (2) sunlight through plate glass, and (3) sunlight through one of the more permeable glasses now on the market.' In both types of experiments we used cubical wooden boxes about twenty inches in diameter. Each box had a removable top, which could be taken out to allow the sun's rays to enter the box unimpeded, or which could be replaced by plate glass or by the more glass. The boxes