Saturated Humidity Research Articles

Lignin and gum deposition in wounded ‘Oroval’ clementines as affected by chilling and peel water content

Induction of lignin synthesis and gum deposition by wounding in the albedo and flavedo of ‘Oroval’ clementines exposed to low temperature has been studied. Wounded and non-wounded fruit were kept for 24 h at 20 °C (initial separate experiment), six and 18 days at 2.5 °C (cold storage), and 18 days at 2.5 °C plus two additional days at 20 °C (shelf-life). At 2.5 °C, fruit were kept under two different conditions: saturated humidity or at 85–90% relative humidity (RH). During the separate initial control and shelf-life periods RH was 60%. The greatest weight loss (WL) was found in wounded fruit stored at 85–90% RH. Chilling injury (CI) was enhanced by wounding in all treatments. The most severe water loss occurred in flavedo of wounded fruit kept at 85–90% RH but, not surprisingly, at saturated humidity, no difference was found. Albedo water content was lower than that of flavedo and decreased again after shelf-life. Cell wall residue (CWR) progressively increased during cold storage in both albedo and flavedo of wounded fruit kept at 85–90% RH. Lignin-thioglycolic compounds increased in flavedo and albedo of wounded fruit kept at 20 °C during the 24-h period of the separate initial control. Under cold storage, however, these compounds did not increase together with CI development and fruit senescence. Wounding, CI and senescence considerably increased the deposition of ethanol-extractable phloroglucinol/HCl- (pg/HCl) positive compounds in flavedo, indicating (specific test) that wound gum deposition was more likely related than lignin biosynthesis to healing process and to pitting development under chilling conditions.

Enhanced production of bovine blastocysts in defined media with appropriate polyvinyl alcohol (PVA) and HEPES concentrations

The objective of this study was to determine optimal gas atmosphere conditions for in vitro maturation (IVM) and in vitro fertilization (IVF) of bovine oocytes. In Experiment 1, groups of 10 to 12 cumulus-oocyte complexes (COCs) were matured (24 h) and fertilized (18 h) under 1) 5% CO2, 5% O2; 2) 5% CO2, 10% O2 or 3) 5% CO2, 20% 02. The COCs were cultured in 50 μl drops of maturation medium (TCM-199 + 10% bovine calf serum + oLH, oFSH and estrogen) or fertilization medium (TALP + swim-up separated spermatozoa +1 μg/ml heparin sulfate) under a layer of 10 ml paraffin oil at 39 °C with saturated humidity. Half of the oocytes in each drop were assigned randomly for maturation scoring and the remainder were inseminated. Reduced atmospheric O2 drastically decreased proportions of oocytes reaching MII (71.4, 26.9 and 9.3% with 20, 10 and 5% O2, respectively; P < 0.05). The percentages of total fertilization in 10 and 20% O2 were similar and considerably higher than in 5% O2 (80.3, 87.0 and 53.1%, respectively; P < 0.05). In addition, the percentage of polyspermy markedly increased when IVF was conducted in reduced O2 (26.6 and 28.8% in 5 and 10% O2 vs 15.4% in 20% O2; P < 0.05). Experiment 2 was similar to Experiment 1 except that CO2 was the variable: 1) 2.5% CO2 in air, 2) 5% CO2 in air and 3) 10% CO2 in air. The proportion of MII oocytes did not differ across treatments (64.9, 68.9 and 61.9%, respectively; P > 0.05). Although the percentages of total fertilization among treatments were not different (75.4, 80.9 and 76.1%, respectively), the proportion of normal fertilization was significantly reduced in 10% C02 (55.1%) when compared with that of either 2.5% CO2 (62.7%) or 5% CO2 (68.7%; P < .05). This study indicates that low O2 is detrimental for IVM/IVF of bovine oocytes and that optimal atmospheric conditions are either 2.5 or 5% CO2 and 20% O2.

Influência da brisa terra-mar no período de saturação da umidade do ar no interior de dois seringais de cultivo em Ubatuba(SP)

Avaliou-se, em Ubatuba(SP), a influência da brisa terra-mar no número de horas com umidade relativa igual ou superior a 90% (NHUR &gt; 90%) no interior de dois seringais [Hevea brasiliensis (Willd. ex Adr. de Juss) Müell Arg.] adultos: um próximo à praia (800 m) e outro distante 5.000 m. Para o período estudado, os resultados demonstraram uma redução significativa do NHUR &gt; 90%, 50% em média, no seringal próximo à praia. A diferença ficou mais evidente, 71,4% em média, quando se analisaram apenas os dias não chuvosos, a fim de desconsiderar a saturação atmosférica devida à chuva. Os resultados deste estudo mostram que a advecção condicionada pela brisa terra-mar é fator aerodinâmico de mesoescala que interfere no início e no final da saturação da umidade atmosférica, reduzindo a duração do período de molhamento das folhas.

Calcium Silicate Carbonation Products

calcium silicates such as C3S, βT‐C2S, and γgM‐C2S† were carbonated under saturated humidity at room temperature. Carbonation products were examined by DT‐TGA, gasphase mass spectroscopy, and XRD. Two types of carbonate were produced: one type, which was rather poorly crystallized, was decarbonated at a very low temperature, below 600°C; the other type was a crystalline phase such as calcite, aragonite, and/or vaterite which was decarbonated above 600°C. The data were compared to existing data for calcium carbonates and basic calcium carbonates. The results suggest that an amorphous calcium silicate hydrocarbonate was one of the carbonation products which formed during the hydration/carbonation reaction.

Optimum gas atmosphere for in vitro maturation and in vitro fertilization of bovine oocytes

The objective of this study was to determine optimal gas atmosphere conditions for in vitro maturation (IVM) and in vitro fertilization (IVF) of bovine oocytes. In Experiment 1, groups of 10 to 12 cumulus-oocyte complexes (COCs) were matured (24 h) and fertilized (18 h) under 1) 5% CO 2, 5% O 2; 2) 5% CO 2, 10% O 2 or 3) 5% CO 2, 20% 0 2. The COCs were cultured in 50 μl drops of maturation medium (TCM-199 + 10% bovine calf serum + oLH, oFSH and estrogen) or fertilization medium (TALP + swim-up separated spermatozoa +1 μg/ml heparin sulfate) under a layer of 10 ml paraffin oil at 39 °C with saturated humidity. Half of the oocytes in each drop were assigned randomly for maturation scoring and the remainder were inseminated. Reduced atmospheric O 2 drastically decreased proportions of oocytes reaching MII (71.4, 26.9 and 9.3% with 20, 10 and 5% O 2, respectively; P < 0.05). The percentages of total fertilization in 10 and 20% O 2 were similar and considerably higher than in 5% O 2 (80.3, 87.0 and 53.1%, respectively; P < 0.05). In addition, the percentage of polyspermy markedly increased when IVF was conducted in reduced O 2 (26.6 and 28.8% in 5 and 10% O 2 vs 15.4% in 20% O 2; P < 0.05). Experiment 2 was similar to Experiment 1 except that CO 2 was the variable: 1) 2.5% CO 2 in air, 2) 5% CO 2 in air and 3) 10% CO 2 in air. The proportion of MII oocytes did not differ across treatments (64.9, 68.9 and 61.9%, respectively; P > 0.05). Although the percentages of total fertilization among treatments were not different (75.4, 80.9 and 76.1%, respectively), the proportion of normal fertilization was significantly reduced in 10% C0 2 (55.1%) when compared with that of either 2.5% CO 2 (62.7%) or 5% CO 2 (68.7%; P < .05). This study indicates that low O 2 is detrimental for IVM/IVF of bovine oocytes and that optimal atmospheric conditions are either 2.5 or 5% CO 2 and 20% O 2.

The Relationship between Sea Surface Temperature and Latent Heat Flux in the Equatorial Pacific

Abstract Moored buoy data from the equatorial Pacific are analyzed to investigate the relationship between sea surface temperature (SST) and latent heat flux from the ocean. It is found that at low SST the latent heat flux increases with SST; at high SST the latent heat flux decreases with increasing SST, a relationship that cannot be explained by thermodynamic considerations alone. Analysis of the wind speeds and humidity differences between the surface air and the saturation humidity at the sea surface temperature indicates that while at low SST the humidity difference primarily determines the latent heat flux, and at high SST a sharp decrease in wind speed is mostly responsible for the low latent heat flux. A mechanism that leads to low latent heat flux at high SST is suggested; it involves the interaction between convection and the large-scale circulation. The longitudinal distribution of SST, wind speed, humidity difference, and latent heat flux is found to be similar to that in previous studies. In ...

Genetic variation for resistance and acclimation to high temperature stress in Drosophila buzzatii

Genetic variation for resistance to a high temperature stress under saturated humidity was examined within and among three Drosophila buzzatii populations from Australia. Further, the acclimation of this species to high temperatures was tested by pretreating flies for a shorter, sublethal, time period under conditions that lead to expression of heat shock proteins. Genetic variation for temperature resistance was present among lines for flies either pretreated to high temperature or not. Pretreating increased survival, with the benefit significantly higher if pretreating was performed 24 h rather than 96 h before exposure to the potentially lethal stress. For flies pretreated at both times, resistance to heat stress was even greater. The lack of a significant treatment by line interaction term suggested that all lines were similarly plastic for acclimation following previous exposure(s) to a high temperature. Significantly more males survived the heat stress than females, and, within each sex, larger flies were generally more heat resistant than smaller ones. Additionally, the lines from the population that naturally encounters the highest temperatures were generally more resistant to high temperature stress.

Genetic variation for resistance and acclimation to high temperature stress in Drosophila buzzatii

Abstract Genetic variation for resistance to a high temperature stress under saturated humidity was examined within and among three Drosophila buzzatii populations from Australia. Further, the acclimation of this species to high temperatures was tested by pretreating flies for a shorter, sublethal, time period under conditions that lead to expression of heat shock proteins. Genetic variation for temperature resistance was present among lines for flies either pretreated to high temperature or not. Pretreating increased survival, with the benefit significantly higher if pretreating was performed 24 h rather than 96 h before exposure to the potentially lethal stress. For flies pretreated at both times, resistance to heat stress was even greater. The lack of a significant treatment by line interaction term suggested that all lines were similarly plastic for acclimation following previous exposure(s) to a high temperature. Significantly more males survived the heat stress than females, and, within each sex, larger flies were generally more heat resistant than smaller ones. Additionally, the lines from the population that naturally encounters the highest temperatures were generally more resistant to high temperature stress.

Interannual Variability in Meterrancan Heat and Buoyancy Fluxes

Abstract The flux of heat through the Strait of Gibraltar is known well enough that the Mediterranean Sea may be used as a climate test basin. After adjusting reported winds for changes in observing practice, the COADS for 1946 to 1988 was used together with standard heat flux formulas to estimate the long-term mean heat flux into the sea, giving 36 W mm2 more than is compatible with the Gibraltar exchange. As the estimated latent heat flux is consistent with the freshwater budget, it is suggested that standard formulas overestimate insulation in the Mediterranean. If a constant adjustment factor is used for the insulation, or for the latent heat loss, interannual variability of ±15 W m−2 is found in the total heat flux. Changes in the latent heat flux dominate, with contributions from both the humidity of the air and the saturation humidity at the temperature of the sea surface. The buoyancy flux from the sea is also examined and shows that the contributions from precipitation and runoff are import...

Effect of ethanol and progesterone on monoamine oxidase activity in cultured cells of human term placenta

The aim of this study was to evaluate the effect of ethanol and progesterone on the monoamine oxidase activity in cultured human term placental cells. Human placental cells were prepared from normal human term placentas by enzymatic dispersion in Dulbecco's modified Eagle medium. The viability of placental cells prepared by our method was 90%, and the yield of placental cells was 0.6 x 10(6) cells per gram of wet placental tissue. Five milliliters of Dulbecco's modified Eagle medium containing 3 x 10(5) placental cells was plated in a 25 cm2 flask and cultured for 8 days in an incubator at 37 degrees C under an atmosphere of 5% carbon dioxide and 95% oxygen with a saturated humidity. During the culture period the culture medium was replenished every 2 days. A confluent monolayer condition was achieved after 8 days in culture. The cultured placental cells were treated with different concentrations of ethanol (0, 34.6, and 69.2 mmol/L) and progesterone (0, 16, and 32 mumol/L) on day 8 of culture for 48 hours. At the end of treatment placental cells from control and treated flasks were harvested for the analysis of monoamine oxidase activity by spectrophotometry. The effects of ethanol and progesterone on cultured placental cells were statistically analyzed by one-way analysis of variance followed by Duncan's multiple comparisons procedure. A human placental cell culture system has been established from normal human term placentas. The monoamine oxidase activity in 8-day-cultured human term placental cells was significantly higher than that of freshly prepared placental cells. Ethanol concentrations at 34.6 and 69.2 mmol/L significantly increased and progesterone concentration at 32 mumol/L significantly decreased the monoamine oxidase activity. These results suggest that the cultured human term placental cells can be used to examine the in vitro effects of ethanol and progesterone on monoamine oxidase activity. However, the physiologic significance of progesterone's inhibitory effect and the stimulatory effect of ethanol monoamine oxidase activity in the in vivo system have yet to be further investigated.

Bacterial Survival on Cornstarch-Containing Polyethylene Film Held Under Food Storage Conditions

Plastics in which cornstarch is incorporated into the polymer network have been developed. The effect of cornstarch in plastic film on the survival of spoilage and pathogenic bacteria was evaluated. Cornstarch-containing polyethylene film (CSPE) and control polyethylene film (PE) were inoculated with Salmonella typhimurium, Aeromonas hydrophila, Bacillus cereus, and Pseudomonas fragi and held under various combinations of temperature and relative humidity to mimic food storage conditions. Bacterial recovery from film samples indicated that, in general, survival was not enhanced by the presence of cornstarch. Enhanced growth of S. typhimurium, A. hydrophila, and P. fragi was observed under saturated relative humidity at some storage temperatures when a CSPE-supplemented minimal salts medium was used as compared to PE-supplemented medium. Enhanced growth was not apparent when a nutritionally complex growth medium supplemented with CSPE or PE was used. These results indicated that, from a microbiological viewpoint, cornstarch-containing polyethylene film could be successfully used to package foods.

Potential Evaporation and Soil Moisture in General Circulation Models

Abstract The parameterization of continental evaporation in many atmospheric general circulation models (GCMS) used for simulation of climate is demonstrably inconsistent with the empirical work upon which the parameterization is based. In the turbulent transfer relation for potential evaporation, the climate models employ the modeled actual temperature to evaluate the saturated surface humidity, whereas the consistent temperature is the one reflecting cooling by the hypothetical potential evaporation. A simple theoretical analysis and some direct computations, all ignoring atmospheric feedbacks, indicate that whenever the soil moisture is limited, GCM-based climate models produce rates of potential evaporation that exceed, by a factor of two or more, the rates that would be yielded by use of the consistent temperature. Further approximate analyses and supporting numerical simulations indicate that the expected value of dry-season soil moisture has a short memory relative to the annual cycle and that dry-...

Wärmestrahlung - ein wesentlicher Faktor des Wärmetransportes bei der kalorischen Vestibularisprüfung?

According to the accepted theory, in vestibular testing the caloric stimulus is transported from the auditory canal to the lateral semicircular canal by heat conduction via the bone. Some findings, however, are not consistent with this concept, e.g. the short latency of the vestibular response, and the fact that removing of the osseous bridge does not stop the transport of heat to the semicircular canal. Physically there are three modes of heat transport: conduction, convection, and radiation. So far, only the first two have been discussed with regard to vestibular calorization, however, they fail to explain the findings mentioned above. We carried out experiments on 10 cadaveric temporal bone specimens in order to evaluate the possible effect of heat radiation. With experimental conditions strictly regulated (specimens kept in climate box, 37 degrees C, saturated humidity, standardized irrigation of the auditory canal with 50 ml of water of 50 degrees C in 15 sec., temperature measured by thermistors at selected points of the specimen), the deviation in repeated experiments was within 0.1 degree C. In normal temporal bones a spreading of heat along the osseous structures was found in accordance with heat conduction via the bone. Then the bony bridge between posterior frame of the tympanic membrane and the lateral canal was removed along with the tegmen tympani, leaving the auditory canal and labyrinth connected only by a small anterior-inferior strut. The rise of temperature in the lateral canal, however, was not delayed and reduced, as expected, but faster and greater than in the original situation. If, now, a reflecting shield was inserted in the cleft between tympanic membrane and labyrinth the heat transfer was dramatically reduced. A similar effect could be achieved in the intact middle ear by a shield or by filling the cavity with gel. Convection as means of heat transport could be excluded. The experiments show that heat transport in the vestibular calorization is a complex process, which besides heat conduction involves radiation as an essential factor. This explains a number of experimental and clinical findings that, so far, had been unclear.

Numbers of small follicles in ovaries affect superovulation response in cattle

The global demand for in vitro–produced (IVP) embryos of determined sex has greatly increased over the last decade. Efficient protocols for the direct transfer of IVP embryos are lacking. This study aimed to compare the pregnancy rates for fresh, vitrified, or frozen/directly transferred IVP dairy cow embryos. Oocytes (n = 3171) recovered by ovum pickup (n = 112) from Girolando (Holstein–Gir) females (n = 36) were selected and submitted to IVM for 24 hours at 38.5 °C with 5% CO2 in air with saturated humidity. In vitro fertilization was performed with the thawed, sexed semen from 5 Holstein bulls. After IVF, presumptive zygotes were denuded and cultured for 7 days under the same IVM and IVF conditions of temperature and humidity, except with 5% CO2 and 5% O2. Grade I blastocysts were randomly assigned for either the transferred fresh, vitrified/thawing, or frozen/directly embryo transfer into previously synchronized recipient females. Conception rates were analyzed by binomial logistic regression, and a probability level of P < 0.05 was considered significant. The conception rates were 51.35 ± 1.87% (133/259) for the fresh embryos, 35.89 ± 3.87% (84/234) for the vitrified embryos, and 40.19 ± 4.65% (125/311) for the frozen directly transferred embryos. These data demonstrate that IVP embryos with sexed semen could be directly transferred into recipient cows with similar conception rates to vitrified embryos. The comparison found that the use of frozen embryos in direct transfer provides easier logistics and a more practical approach for the transfer of IVP embryos on dairy farms.

Genetic and environmental factors in the resistance of Drosophila subobscura adults to high temperature shock

We have carried out two equivalent selection experiments to increase and decrease heat shock resistance of Drosophila subobscura adults, using an indirect selection method that avoids excessive consanguinity. Heat shock was 33±0.5 °C at saturation humidity. Control lines showed a rapid change of the physiological trait as a consequence of laboratory culture conditions, expressed as a decrease both in heat shock resistance and in the initial population variability for heat shock resistance. Thus, this reduction of variability seems to consist in the loss of those combinations of genes that confer high resistance to heat shock. After eight generations of selection, the selected lines were differentiated from their respective control lines, and the selection response obtained was similar in "resistant" and "sensitive" lines. Differences in survival of progeny of reciprocal crosses between selected lines suggest that inheritance of heat resistance may depend in part on the origin of egg cytoplasm.

Phomopsis asparagi . [Descriptions of Fungi and Bacteria

Abstract A description is provided for Phomopsis asparagi . Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Asparagus officinalis, A. plumosus, A. verticillatus . DISEASE: Stem blight of Asparagus species. The first symptom is a discolouration of the stem tissue followed by the appearance of brown, elliptical lesions. As infection progresses the affected areas become shrivelled and turn into well defined spots surrounded by dark brown margins. The centre of these spots become ashy-white with numerous immersed pycnidial conidiomata which later become erumpent. As disease advances the growth of the lateral branches is frequently arrested. All parts of the plant except the berries are susceptible to infection. In severe cases needles turn yellow, the plants are partially or completely defoliated and finally wither (16, 12; 55, 2446; 67, 1628). GEOGRAPHICAL DISTRIBUTION: Africa (Ethiopia), Asia (India, China-Shanghai, Malaysia, Pakistan, Siberia, Taiwan); Europe (France, Germany, Italy, Spain, Yugoslavia); North America (Eastern U.S.A., Alabama, Arkansas, New Jersey). TRANSMISSION: Through plant debris in soil (67, 4258; Kheswalla, 1936). Infection occurs rapidly through wounds. It has been found that conidia are discharged from pycnidial conidiomata by immersion in water, spraying with water and saturated high humidity. Longevity of conidial ooze was affected by spore cone., and undiluted spore ooze retained 41% germination after desiccation for 1 month (67, 4259). Survival of conidia in soil is affected by temperature and moisture. It has been reported that all conidia were destroyed after exposure to 35°C for 2 d; only 14% remained viable after 30 d at 10°C. At 28°C, conidia survived longer in dry than in wet soil. The fungus survived on infected stems buried in the soil during ploughing or in the ground for 3-4 months. On diseased stems at soil surface the pathogen survived &gt; 6 months (67, 4258).

The sensitivity of latent heat flux to the air humidity approximations used in ocean circulation models

In deriving the surface latent heat flux with the bulk formula for the thermal forcing of some ocean circulation models, two approximations are commonly made to bypass the use of atmospheric humidity in the formula. The first assumes a constant relative humidity, and the second supposes that the sea‐air humidity difference varies linearly with the saturation humidity at sea surface temperature. Using climatological fields derived from the Marine Deck and long time series from ocean weather stations, the errors introduced by these two assumptions are examined. In the extratropical oceans, large meridional and seasonal variations of relative humidity are found, and the seasonal cycle of sea‐air humidity difference is out of phase with that of sea surface temperature. The air humidity reaches the minimum earlier than the sea surface temperature during winter cooling. The errors reach above 100 W/m2 over western boundary currents and 50 W/m2 over the tropical ocean. The two approximations also introduce erroneous seasonal and spatial variabilities with magnitudes over 50% of the observed variabilities. Meteorological reports from atolls in the tropical Pacific indicated that in the atmosphere the humidity anomalies were much more pronounced than the temperature anomalies as the center of deep convection was dislocated during the 1982–1983 El Niño‐Southern Oscillation episode.

Genetic and environmental factors in the resistance of Drosophila subobscura adults to high temperature shock

Survival time following a high temperature shock of Drosophila subobscura adults in dry air has shown great variability. This experimental condition involved desiccation as the first cause of death. Here survival is studied under saturation humidity, so that the mortality may be imputed only to thermic stress. We analyze the influence of culture temperature and crowding on resistance for different sex and age of the adults. The results show strong influences of these environmental factors on heat shock resistance and show interactions with the age and sex of the adults. We suggest that these facts could be due to acclimatization and/or to adaptation. The acclimatization would occur during development and would affect physiological processes related to aging of the flies. The adaptation would take place for selection, acting through differential mortality before the heat shock. Of course, other processes could be significant. Whatever the causal explanation, it will be necessary in any future research related with heat shock resistance to take these factors into account.

ChemInform Abstract: An Investigation of Phase Transitions in Rust Layers Using Raman Spectroscopy.

AbstractThe rusting process of electroplated iron layers on gold substrates in 0.5% SO2 atmosphere with saturated humidity is investigated using in situ Raman spectroscopy.

Developpement de Leveillula taurica en Fonction des Facteurs Climatiques et Sensibilité de Capsicum annuumà Differents Stades Végétatifs

AbstractInfluence of environmental factors on the development of L. taurica on pepper genotypes To our knowledge, the effects of certain environmental factors, as well as those of host genotype on the development of Leveillula taurica on pepper have not been extensively investigated. To study effects of the above factors on the development of this parasite, two Capsicum genotypes (‘Yolo Wonder' and ‘line 815’) have been tested and compared under different light and relative humidity conditions. In vitro, optimal light intensity for spore germination was situated between 20 and 80 μE/m2/s, and for the growth of germ tubes it was 20 μE/m2/s. In vivo, under continous darkness during 20 days, the different organs of the hosts were only slightly affected. Under light conditions, during 20 days after inoculation, the highest infection level on leaves was observed at 20 μE/m2/s, (60 % of leaves) while with the cotyledons it was observed between 20–80 μE/m2/s.Effects of relative humidity on the development of this parasite were also studied on ‘Yolo Wonder’ and ‘line 815′. With relative humidity below 50 %, 60 % of ‘Yolo Wonder’ plants and 33 % of ‘line 815’ were infected. Under conditions of saturated relative humidity, the level of infection was the inverse, i. e. 13 and 55 %, respectively.Moreover, ‘Yolo Wonder’ plants were found more or less susceptible to infection with L. taurica during their different development stages. At the cotyledon stage all plants were infected. After this stage, up to flowering, susceptibility depended on the physiological age of the leaves. First leaves (older leaves) were not infected, while young ones near the apex became progressively susceptible.