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Dew is an important water input and promotes plant growth. Dew condenses on plant leaves at night, and a portion of this dew returns to the atmosphere through evaporation. The amount of dew that evaporates is not equal to the amount of condensation; however, the dew evaporation process has not received enough attention. By monitoring the dew condensation and evaporation processes associated with four typical shrubs (Syringa, Hemiptelea, Buxus, and Cornus) in northeast China, we found that dew condensation started approximately 30 min after sunset, finished approximately 30 min before sunrise, and then turned to the evaporation phase. Dew had completely depleted approximately 4 h after sunrise. The dew evaporation period was negatively correlated with the wind speed (p < 0.01) and positively correlated with temperature, solar radiation, and relative humidity (RH) (p < 0.01). The average evaporation periods of Syringa, Buxus, Cornus, and Hemiptelea were 282 ± 21 min, 255 ± 26 min, 242 ± 22 min, and 229 ± 17 min, respectively. The daily evaporation amounts in May and September reached the minimum and maximum values, respectively, and the evaporation intensity of dew was positively correlated with RH (p < 0.01). There was no significant difference in the daily evaporation amounts of Syringa, Hemiptelea, Buxus, or Cornus (p > 0.05), and the annual evaporation amounts of these four plants were 17.05 mm/y, 16.38 mm/y, 21.94 mm/y, and 16.15 mm/y, respectively. The microstructure of leaves affected both the rate and amount of evaporation. Dew evaporated faster on hydrophilic leaves, and leaves with high trichome and stomatal densities had lower proportions of the dew evaporation amount to the condensation amount. The proportions of the dew evaporation amount to the condensation amount derived for Syringa, Hemiptelea, Buxus, and Cornus were 60.38%, 46.07%, 57.24%, and 52.81%, respectively. This study supplements our understanding of dew evaporation amounts, providing information that was missing in the near-surface hydrological cycle and aiding in the assessment of the ecological significance of dew to plants.

For a good interpretation of radar backscatter sensitivity to vegetation water dynamics, we need to know which parts of the vegetation layer control that backscatter. However, backscatter sensitivity to different depths in the canopy is poorly understood. This is partly caused by a lack of observational data to describe the vertical moisture distribution. In this study, we aimed to understand the sensitivity of L-band backscatter to water at different heights in a corn canopy. We studied changes in the contribution of different vertical layers to total backscatter throughout the season and during the day. Using detailed field measurements, we first determined the vertical distribution of moisture in the plants, and its seasonal and sub-daily variation. Then, these measurements were used to define different sublayers in a multi-layer water cloud model (WCM). To calibrate and validate the WCM, we used hyper-temporal tower-based polarimetric L-band scatterometer data. WCM simulations showed a shift in dominant scattering from the lowest 50 cm to 50–100 cm during the season in all polarizations, mainly due to leaf and ear growth and corresponding scattering and attenuation. Dew and rainfall interception raised sensitivity to upper parts of the canopy and lowered sensitivity to lower parts. The methodology and results presented in this study demonstrate the importance of the vertical moisture distribution on scattering from vegetation. These insights are essential to avoid misinterpretation and spurious artefacts during retrieval of soil moisture and vegetation parameters.

During dry spells, non-rainfall water (hereafter NRW) mostly formed from dew and fog potentially plays an increasingly important role in temperate grassland ecosystems with ongoing global warming. Dew and radiation fog occur in combination during clear and calm nights, and both use ambient water vapor as a source. Research on the combined mechanisms involved in NRW inputs to ecosystems is rare, and distillation of water vapor from the soil as a NRW input pathway for dew formation has hardly been studied. Furthermore, eddy covariance (EC) measurements are associated with large uncertainties on clear, calm nights when dew and radiation fog occur. The aim of this paper is thus to use stable isotopes as tracers to investigate the different NRW input pathways into a temperate Swiss grassland at Chamau during dry spells in summer 2018. Stable isotopes provide additional information on the pathways from water vapor to liquid water (dew and fog) that cannot be measured otherwise. We measured the isotopic composition (δ18 O, δ2 H, and d=δ2H-8⋅δ18O) of ambient water vapor, NRW droplets on leaf surfaces, and soil moisture and combined them with EC and meteorological observations during one dew-only and two combined dew and radiation fog events. The ambient water vapor d was found to be strongly linked with local surface relative humidity (r=-0.94), highlighting the dominant role of local moisture as a source for ambient water vapor in the synoptic context of the studied dry spells. Detailed observations of the temporal evolution of the ambient water vapor and foliage NRW isotopic signals suggest two different NRW input pathways: (1) the downward pathway through the condensation of ambient water vapor and (2) the upward pathway through the distillation of water vapor from soil onto foliage. We employed a simple two-end-member mixing model using δ18 O and δ2 H to quantify the NRW inputs from these two different sources. With this approach, we found that distillation contributed 9 %–42 % to the total foliage NRW, which compares well with estimates derived from a near-surface vertical temperature gradient method proposed by Monteith in 1957. The dew and radiation fog potentially produced 0.17–0.54 mm d -1 NRW gain on foliage, thereby constituting a non-negligible water flux to the canopy, as compared to the evapotranspiration of 2.7 mm d -1. Our results thus underline the importance of NRW inputs to temperate grasslands during dry spells and reveal the complexity of the local water cycle in such conditions, including different pathways of dew and radiation fog water inputs. [ABSTRACT FROM AUTHOR]

Long‐term (1961–2010) observations of dew data collected at 597 stations over China show that dew frequency decreased by 5.2 days per decade due primarily to near‐surface warming and associated decreases in relative humidity (RH). Moreover, the percentage decreasing rate of dew frequency in arid regions (precipitation PR <400 mm yr−1) are larger than that in humid regions (PR ≥800 mm yr−1). Compared with the 1960s, the mean dew frequency in the 2000s decreased by 28%, 40%, 50% in humid, semihumid (400 ≤ PR < 800 mm yr−1), and arid regions, respectively. Surface warming is larger in arid regions in northwestern China than its humid and semihumid regions during recent global warming, which leads to larger decreases in surface RH and makes dew events less likely. Since dew contributes significantly to surface water balance in arid regions, the large decreases in dew frequency may contribute to "the drier getting drier" response to global warming over arid regions. Plain Language Summary: Here we show, by analyzing 50 years (1961–2010) of data collected at 597 stations in China, that dew occurrence in China exhibits a clear decreasing trend, and the decreasing rate of dew frequency in arid regions is higher than that in semihumid and humid regions. Compared with the 1960s, the mean dew frequency in the 2000s decreased by 28%, 40%, 50% in the humid, semihumid, and arid regions of China, respectively. Further analysis reveals that the decreased dew frequency is caused primarily by near‐surface warming and drying. Large decreases in surface relative humidity in arid regions associated with large warming makes dew events less likely. This could make the region drier as dew is a significant water source in arid regions. Key Points: Near‐surface warming has induced significantly decline of dew occurrence in ChinaThe decreasing rate of dew frequency in arid regions is higher than that in semihumid and humid regionsThis finding sheds new understanding of the issue of "drier getting drier" for arid regions under global warming [ABSTRACT FROM AUTHOR]

A plant's foliar uptake of dew can mitigate the adverse effects caused by drought stress. However, in grassland ecosystems, it is inconclusive whether the dew condensation characteristics of plants at different heights are consistent. In this study, we wanted to know whether plant height had a significant effect on the formation of dew. In addition, we wanted to understand the difference of dew formation between C3 plant Leymus chinensis (LC) and C4 plant Cleistogenes squarrosa (CS) which have different heights and can succeed each other in the community. In nine dew nights, we measured the amount of dew formed on simulated condensation surface (different heights) and two plants at the same time. The results showed that in the height range of 5-80 cm, the dew amount increases with the canopy height, but its increase rate gradually slows down and approaches zero. The shorter CS (5-15 cm) has a similar dew amount (0.095 mm) as LC (40-70 cm) due to its compact structure of the leaves with pubescence and the more stable micro-meteorological conditions. The CS can obtain more potential dew per unit organic matter, and this may be one of the potential mechanisms for the succession from LC communities to CS communities under drought stress. [ABSTRACT FROM AUTHOR]

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Mobile grid computing has been a popular topic for researchers due to mobile and IoT devices' ubiquity and their evergrowing processing potential. While many scheduling algorithms for harnessing these resources exist in the literature for standard grid computing scenarios, surprisingly, there is little insight into this matter in the context of hybrid-powered computing resources, typically found in Dew and Edge computing environments. This paper proposes new algorithms aware of devices' power source for scheduling tasks in hybrid environments, i.e., where the battery- and non-battery-powered devices cooperate. We simulated hybrid Dew/Edge environments by extending DewSim, a simulator that models battery-driven devices' battery behavior using battery traces profiled from real mobile devices. We compared the throughput and job completion achieved by algorithms proposed in this paper using as a baseline a previously developed algorithm that considers computing resources but only from battery-dependent devices called Enhanced Simple Energy-Aware Schedule (E-SEAS). The obtained results in the simulation reveal that our proposed algorithms can obtain up to a 90% increment in overall throughput and around 95% of completed jobs in hybrid environments compared to E-SEAS. Finally, we show that incorporating these characteristics gives more awareness of the type of resources present and can enable the algorithms to manage resources more efficiently in more hybrid environments than other algorithms found in the literature. [ABSTRACT FROM AUTHOR]

Manipulative experiments typically show a decrease in dryland biocrust cover and altered species composition under climate change. Biocrust‐forming lichens, such as the globally distributed Diploschistes diacapsis, are particularly affected and show a decrease in cover with simulated climate change. However, the underlying mechanisms are not fully understood, and long‐term interacting effects of different drivers are largely unknown due to the short‐term nature of the experimental studies conducted so far.We addressed this gap and successfully parameterised a process‐based model for D. diacapsis to quantify how changing atmospheric CO2, temperature, rainfall amount and relative humidity affect its photosynthetic activity and cover. We also mimicked a long‐term manipulative climate change experiment to understand the mechanisms underlying observed patterns in the field.The model reproduced observed experimental findings: warming reduced lichen cover, whereas less rainfall had no effect on lichen performance. This warming effect was caused by the associated decrease in relative humidity and non‐rainfall water inputs, which are major water sources for biocrust‐forming lichens. Warming alone, however, increased cover because higher temperatures promoted photosynthesis during early morning hours with high lichen activity. When combined, climate variables showed non‐additive effects on lichen cover, and effects of increased CO2 levelled off with decreasing levels of relative humidity.Synthesis. Our results show that a decrease in relative humidity, rather than an increase in temperature, may be the key factor for the survival of the lichen D. diacapsis under climate change and that effects of increased CO2 levels might be offset by a reduction in non‐rainfall water inputs in the future. Because of a global trend towards warmer and drier air and the widespread global distribution of D. diacapsis, this will affect lichen‐dominated dryland biocrust communities and their role in regulating ecosystem functions worldwide. [ABSTRACT FROM AUTHOR]

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Non-rainfall moisture (fog, dew, and water vapor; NRM) is an important driver of plant litter decomposition in grasslands, where it can contribute significantly to terrestrial carbon cycling. However, we still do not know whether microbial decomposers respond differently to NRM and rain, nor whether this response affects litter decomposition rates. To determine how local moisture regimes influence decomposer communities and their function, we examined fungal communities on standing grass litter at an NRM-dominated site and a rain-dominated site 75 km apart in the hyper-arid Namib Desert using a reciprocal transplant design. Dominant taxa at both sites consisted of both extremophilic and cosmopolitan species. Fungal communities differed between the two moisture regimes with environment having a considerably stronger effect on community composition than did stage of decomposition. Community composition was influenced by the availability of air-derived spores at each site and by specialization of fungi to their home environment; specifically, fungi from the cooler, moister NRM Site performed worse (measured as fungal biomass and litter mass loss) when moved to the warmer, drier rain-dominated site while Rain Site fungi performed equally well in both environments. Our results contribute to growing literature demonstrating that as climate change alters the frequency, magnitude and type of moisture events in arid ecosystems, litter decomposition rates may be altered and constrained by the composition of existing decomposer communities.

Non-rainfall moisture (fog, dew, and water vapor; NRM) is an important driver of plant litter decomposition in grasslands, where it can contribute significantly to terrestrial carbon cycling. However, we still do not know whether microbial decomposers respond differently to NRM and rain, nor whether this response affects litter decomposition rates. To determine how local moisture regimes influence decomposer communities and their function, we examined fungal communities on standing grass litter at an NRM-dominated site and a rain-dominated site 75 km apart in the hyper-arid Namib Desert using a reciprocal transplant design. Dominant taxa at both sites consisted of both extremophilic and cosmopolitan species. Fungal communities differed between the two moisture regimes with environment having a considerably stronger effect on community composition than did stage of decomposition. Community composition was influenced by the availability of air-derived spores at each site and by specialization of fungi to their home environment; specifically, fungi from the cooler, moister NRM Site performed worse (measured as fungal biomass and litter mass loss) when moved to the warmer, drier rain-dominated site while Rain Site fungi performed equally well in both environments. Our results contribute to growing literature demonstrating that as climate change alters the frequency, magnitude and type of moisture events in arid ecosystems, litter decomposition rates may be altered and constrained by the composition of existing decomposer communities. [ABSTRACT FROM AUTHOR]

In order to optimize the energy consumption of the natural gas dew point control system under meeting the requirement of dew point at the junction point, HYSYS model is used to establish steady simulation to perform the sensitivity analysis of the key parameters affecting the dew point,including feed gas pressure and temperature, TEG circulation flowrate, reboiler temperature, stripping gas flowrate and J-T valve front temperature, and the reasonable value range of the key parameters,then the value range of which is determined. On this basis, the process parameters are optimized by the optimizer module of HYSYS and the optimal combination of process parameters is obtained. In view of the phenomenon of natural gas reverse condensation, the product gas envelope is used to check dew point during transporting. The results show that the pressure-temperature curve along the pipeline is on the right side of the dew point line, which proves that the product gas is always transported in gas phase [ABSTRACT FROM AUTHOR]

Rose pure dew is commonly used in food and cosmetic industries. A bacterial was isolated from rose pure dew, followed, the morphological, physiological, biochemical, and molecular biology were used to the identification. The pathogenicity of the strain and the broad‐spectrum antibacterial activity of pure dew were detected. The strain was subjected to testing at temperature gradients as well as to antibacterial tests against food preservatives and drugs. The isolate was considered as Burkholderia cepaciaMG1 carrying toxicity‐related genes. The antibacterial test revealed that only B. cepaciaMG1 could grow normally in pure dew, with the optimum inactivation condition of 52°C for 15 min. It is sensitive to ε‐polylysine hydrochloride, sodium diacetate, kanamycin, nalidixic acid, and ofloxacin. The tested antibiotics could inhibit the pathogen, which provides a theoretical basis for the treatment of patients infected. It is necessary to control the quality of rose pure dew productions, which is helpful for our health. Practical applications: Microbial contamination of food or insufficient/inefficient sterilization during food processing or production can bring about significant economic losses to the food industry as well as pose a serious threat to the health of consumers. In this study, B. cepaciaMG1 was isolated from Ku shui rose dew, and the pathogenicity of the identified isolate was established. Accordingly, the prevention and treatment of B. cepaciaMG1‐contaminated food were conducted by temperature treatment or the use of food preservatives and antibiotics so as to provide a scientific theoretical reference for the prevention and treatment of B. cepaciaMG1 contamination in the food industry. [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: The integument of terrestrial mollusks is highly susceptible to dehydration; therefore, microhabitat selection, seasonality and behavior around the day are crucial to their survival. However, they are still poorly understood, especially for tropical montane wet forest species. Objetive: To analyze activity patterns and microhabitat selection on shrubs of the land snail Tikoconus costarricanus, according to season, daytime and weather. Methods: I conducted the study near "El llano" water dam in a tropical montane wet forest in Costa Rica. I observed daily activity of T. costarricanus, during the rainy and the dry season on a 2 km long trail. I observed 167 specimens and made 781 observations in total. I took note of: season, time, activity, weather, temperature and relative humidity inside the forest, and part of the leaf and height where snails were. Active snails had optical tentacles extended. I analysed daily rainfall data from a nearby meteorological station. Results: This species can be found mainly on understory leaves between 1.1 and 2 m above the floor. They are active the day around during the whole year. Only 24% of the snails were on the upper side of leaves, but 92% of them were active. The following behaviors were season dependent: activity peaks, leaf side selection according to daytime and weather, quantity of snails aestivating and vertical distribution. During the dry season, I found more active snails in rainy and cloudy days. During the rainy season I found more active snails in sunny days. During rainy season light hours, active snail percentage on the upper side of leaves decreased with rainfall increase, while in the dry season decreased with temperature increase and relative humidity decrease. During night hours of both seasons, the number of snails on the upper side of leaves decreased considerably in relation to active snails, especially in the rainy season. This snail aestivated on the underside of leaves during periods shorter than 21 h, mainly around noon and afternoons during the dry season. High humidity in this forest allowed snail activity around the day at any season. However, this species aestivated when moisture reached the lowest values, mainly, around noon and in the afternoons in the dry season. The rainfall pattern during the rainy season light hours explains the specimen decrease on the upper side of leaves, but in the dry season it is better explained by the temperature increase and the decrease in relative humidity. During dark hours, the almost complete snail absence on the upper side of leaves during the rainy season is explained if the effect of canopy drip produced by rain and dew condensed on leaves is added to the rain pattern. The situation is slightly different in dark hours of the dry season, in this case, snail decrease on the upper side of leaves is explained by canopy drip from dew and fog precipitation. Seasonal difference in vertical distribution may be a way to avoid rain and rain splash out on the soil. Conclusions: Moisture, temperature, rain, and canopy drip from dew, fog and rain, affect behavior and substrate selection of small terrestrial mollusks that inhabit shrubs in wet tropical rainforests. [ABSTRACT FROM AUTHOR]

Objective] This paper aimed to improve the hatching rate of walnut, the whole kernel rate and high dew kernel rate. [ Method] Based on Hertz contact theory, the curvature radius of the optimal contact surface was calculated to be - 33.64 mm, and then designed the three different kinds of contact surface which were a plane, concave spherical surface and the the sharp point, respectively. The three contact models were modeled and the static module was used for contact simulation in ANSYS workbench to analyze the stress, strain and deformation cloud map. [ Results ] When the contact surface was a concave sphere, the stress and deformation cloud map had the largest area distribution. Moisture content and compression stroke as well as the interface type chose as the three factors in the orthogonal experiment. Factors level : When the moisture content was 20 %, the extrusion stroke was 6 mm, the contact surface type was concave sphere with curvature radius of 33.64 mm, the shell cracking effect was the best, and the type of contact surface had the most significance influence on the cracking result. [ Conclusion] In the optimal conditions of test results, the comprehensive evaluation value was 2.82, and concave sphere with curvature radius of 33 . 64 mm could significantly improve walnut shell cracking effect. [ABSTRACT FROM AUTHOR]

Abstract Fog and dew are often viewed as economic nuisances causing significant financial losses in the transportation industry and agricultural sector. However, they are also critical components of the hydrological cycle, especially in water scarce environments. Water scarcity is one of the major threats to mankind in the 21st century, and this can be due to development pressures, pollution, and/or expanding populations. In water scarce environments, fog and dew represent potentially exploitable ancillary water resources that could ameliorate the water scarce situation, if efficiently harvested. However, two important issues are often overlooked in relation to fog and dew harvesting and potability. First, current fog and dew harvesting technologies are low yielding with great potential for improvements. Second and more importantly, the potability of these water resources is often based on simple analyses that often omit trace metal and biological analyses. The few studies that report trace metal or biological measurements suggest elevated trace metal concentrations or biological contamination that could be of concern to public health. We discuss the potential for fog and dew harvesting technologies and the need for trace metal and biological analyses of these waters before use.

In recent years, fog-haze weather has frequently occurred in urban ecosystem, with accompanied dew condensation in the surface layer. Dew formation plays an important role in air purification, which takes fine aerosols in the atmosphere as the condensation nuclei. However, the influence of fog-haze on dew condensation remains unclear. Thus, this study aims to evaluate the influences of fog-haze days on the frequency, intensity, and duration of dew condensation, to reveal the factors relevant to dew condensation during weather pollution, and to improve the air quality in fog-haze days. The monitor-based direct weighing method was employed in this study to observe the vapour condensation in urban greenbelt under fog-haze and normal weather conditions during the frost-free season (April-October 2017) in Changchun, China. The differences in dew condensation intensity and frequency were discriminated under different weather conditions. Then, the influences of fog-haze days on the vapour condensation were analyzed by monitoring the velocity and duration of dew condensation in polluted weather. Finally, a program for improving air quality was proposed based on the analysis of major meteorological factors that affect the dew condensation during the fog-haze days. Results show that the dew condensation velocity decreases significantly (P < 0.01) from 0.0067 mm/h in normal weather to 0.0026 mm/h in a fog-haze day, whereas the condensation duration is prolonged. The dew condensation intensities are 0.064, 0.045, and 0.051 mm/d under fog, haze, and normal weather conditions, respectively, and the fog-haze weather has no significant effect on the frequency or intensity of dew condensation (P > 0.05). The particulate matter concentration, wind speed, air pressure, relative humidity, and solar radiation are the main factors that affect the vapour transport during the fog-haze days. Artificial increase of surface layer vapours can promote the particulates to absorb vapours fully and settle to the ground in the form of dew, thereby reducing the particulate matter concentration within the scope of human activities. The present study supplements the eigenvalues for dew condensation in urban areas during special pollution periods and reveals the influence of fog-haze on the night time vapour condensation in urban areas. Findings of this study provide theoretical basis for further developing the programs for controlling fog-haze weather and improving urban air quality.

As an important source of non‐rainfall input of land–surface liquid water, dew has considerable ecological and hydrological significance in desert ecosystems. Dew moisture regime is commonly used for characterizing available dew. It discloses not only the contributions of dew to plants, small animals, and biological crusts but also the mechanism by which desert organisms adapt to extreme climates. By reviewing the existing researches on dew moisture regimes in desert ecosystems, this study reveals the variations in the amount and duration of dew, as well as its influencing factors at site‐, catchment‐, and regional scales, based on the radiation cooling theory and the physical mechanisms of dew formation. Furthermore, it compares the differences in dew moisture between various sites and catchments, illustrates the trends in daily and annual dew moisture in various deserts, and identifies the existing problems of researches on dew moisture regimes amid climate change. The findings of this study enhance preliminary knowledge on the reasonable utilization of dew water, worldwide. This article is categorized under:Science of Water > Hydrological ProcessesWater and Life > Nature of Freshwater Ecosystems [ABSTRACT FROM AUTHOR]

To characterize the role of dew water for the ground surface HONO distribution, nitrous acid (HONO) measurements with a Monitor for AeRosols and Gases in ambient Air (MARGA) and a LOng Path Absorption Photometer (LOPAP) instrument were performed at the Leibniz Institute for Tropospheric Research (TROPOS) research site in Melpitz, Germany, from 19 to 29 April 2018. The dew water was also collected and analyzed from 8 to 14 May 2019 using a glass sampler. The high time resolution of HONO measurements showed characteristic diurnal variations that revealed that (i) vehicle emissions are a minor source of HONO at Melpitz station; (ii) the heterogeneous conversion of NO2 to HONO on the ground surface dominates HONO production at night; (iii) there is significant nighttime loss of HONO with a sink strength of 0.16±0.12 ppbvh-1 ; and (iv) dew water with mean NO2- of 7.91±2.14 µgm-2 could serve as a temporary HONO source in the morning when the dew droplets evaporate. The nocturnal observations of HONO and NO2 allowed the direct evaluation of the ground uptake coefficients for these species at night: γNO2→HONO=2.4×10-7 to 3.5×10-6 , γHONO,ground=1.7×10-5 to 2.8×10-4. A chemical model demonstrated that HONO deposition to the ground surface at night was 90 %–100 % of the calculated unknown HONO source in the morning. These results suggest that dew water on the ground surface was controlling the temporal HONO distribution rather than straightforward NO2 –HONO conversion. This can strongly enhance the OH reactivity throughout the morning time or in other planted areas that provide a large amount of ground surface based on the OH production rate calculation. [ABSTRACT FROM AUTHOR]

Early Jewish and early Christian readers found resurrection from the dead in the tales of Daniel; this article suggests that those readings may uncover real roots of the later theological idea within the earlier texts. The lions' den of chs. 6 and 14 in the Greek texts and their daughter versions has intertextual connections with the pit which figures death in the Psalms, in Jeremiah, and in ancient Near Eastern iconography, and the dew which cools the furnace in the Greek versions of ch. 3 ties that chapter into a network of mythological allusions to the resurrecting power of dew. The Additions to Daniel and their early reception thus create a trajectory towards the later ideas which rabbinic and patristic readers built upon the substratum of these texts; in turn, those later ideas can be shown to have organic antecedents within the book of Daniel. [ABSTRACT FROM AUTHOR]

Models assume that rainfall is the major moisture source driving decomposition. Non-rainfall moisture (NRM: high humidity, dew, and fog) can also induce standing litter decomposition, but there have been few measurements of NRM-mediated decomposition across sites and no efforts to extrapolate the contribution of NRM to larger scales to assess whether this mechanism can improve model predictions. Here, we show that NRM is an important, year-round source of moisture in grassland sites with contrasting moisture regimes using field measurements and modeling. We first characterized NRM frequency and measured NRM-mediated decomposition at two sites in the Namib Desert, Namibia (hyper-arid desert), and at one site in Iowa, USA (tallgrass prairie). NRM was frequent at all sites (85–99% of hours that litter was likely to be wet were attributed to NRM) and tended to occur in cool, high-humidity periods for several hours or more at a time. NRM also resulted in CO2 release from microbes in standing litter at all sites when litter became sufficiently wet (> 5% gravimetric moisture for fine litter and > 13% for coarse), and significantly contributed to mass loss, particularly in the western Namib site that received almost no rain. When we modeled annual mass loss induced by NRM and rain and extrapolated our characterization of NRM decomposition to a final semiarid site (Sevilleta, New Mexico), we found that models driven by rainfall alone underestimated mass loss, while including NRM resulted in estimates within the range of observed mass loss. Together these findings suggest that NRM is an important missing component in quantitative and conceptual models of litter decomposition, but there is nuance involved in modeling NRM at larger scales. Specifically, temperature and physical features of the substrate emerge as factors that affect the microbial response to litter wetting under NRM in our sites, and require further study. Hourly humidity can provide an adequate proxy of NRM frequency, but site-specific calibration with litter wetness is needed to accurately attribute decomposition to periods when NRM wets litter. Greater recognition of NRM-driven decomposition and its interaction with other processes like photodegradation is needed, especially since fog, dew, and humidity are likely to shift under future climates. [ABSTRACT FROM AUTHOR]

The common noun רְבִיבִים occurs six times in the Hebrew Bible (Deut 32:2; Jer 3:3; 14:22; Mic 5:6; Pss 65:10[10]; 72:6). Its contexts clearly suggest that it belongs to the semantic domain of rain and dew, and that it denotes something desirable. But further precision has eluded interpreters, and the much-discussed Ugaritic words rbb and rb are of little help in this regard. The apparent Akkadian cognate rabbu A, unmentioned in the standard Biblical Hebrew lexica, is considered here, and it is argued on that basis that the word means "gentle rain" or "drizzle." [ABSTRACT FROM AUTHOR]

[ Objective]The effects of different non-thermal Sterilization methods on the volatile components and microbes in rose dew were compared in order to provide experimental evidence for commercial sterilization of rose dew. [ Method] The effects of three kinds of non-thermal Sterilization treatments on volatile components in rose dew were detected by headspace-GC-MS, then we tested the effects of three kinds of non-thermal sterilization treatments on microorganisms in rose dew. [ Result] Ultra-high pressure ( UHP) showed advantages over the sterilization by filtration in practical application. UHP ( 550 MPa, 5 mine) treatment effectively killed the microbes, such as yeast and mould in the rose water, with aerobic count plate < 10 CFU/mL; the main aroma components were effectively retained, and two new substances (E) -2 -heptenal and ( E) -3, 7-dimethyl-2, 6 -octandienal were detected. Through the calculation of total alcohols, total acids and total aldehydes in rose dew, we found that the content of alcohol compounds decreased, the content of aldehyde& compounds increased, and the change of the content acid compounds was not obvious in rose dew treated with ultra-through pressure. [ Conclusion] UHP not only efficiently killed the microorganisms in the rose dew, but also improved oxidation and esterification of alcohols and aldehydes, and it could well retain the quality of rose dew. [ABSTRACT FROM AUTHOR]

The importance of populations of the Socotra dragon's blood trees (Dracaena cinnabari Balf.f., 1882) for horizontal precipitation capture was estimated for the first time. Dragon's blood trees (Asparagaceae) inhabit semiarid cloud forests with low levels of rainfall that strongly depend on additional moisture from fog and clouds. Our estimation was based on a detailed description of the aboveground biomass structure of stands of the dragon's blood trees on Socotra Island. The aboveground biomass was described using non-destructive methods. An example of a well-preserved forest was measured in terms of the basic biometric characteristics of each tree, and the trees were divided into three classes based on crown projections. For each class, we took detailed measurements of one representative tree. All measured and counted growth characteristics were converted to the stand level. The tree population at the whole island level was investigated using remotely sensed data. The estimation of horizontal precipitation was performed using detailed and precise evaluation of the available climate data in half-hour intervals over the period of June 2009 and June 2010 and the ambulatory direct measurements (12.6.2009–26.6.2009). The mean annual horizontal precipitation below the crown of the dragon's blood tree was estimated to be 792 mm in the highest (951–1545 m a.s.l.), 373 mm in the middle (601–950 m a.s.l.) and 46 mm in the lowest (180–600 m a.s.l.) altitudinal zones. Our model showed that the horizontal precipitation exceeded 40% of the total annual precipitation. The decline in the dragon's blood tree forest could therefore cause the loss of additional water from the island's hydrological cycle. [ABSTRACT FROM AUTHOR]

The article presents the study which assessed the potential of dew as a supplementary source of water in India' agriculture sector due to the growing water scarcity as a result of climate change. Also cited are the use of descriptive statistical analysis to determine minimum, maximum, mean, standard deviation (SD) and coefficient of variation (CV) of dew deposition, and the suitability of dew water as a source of water in rainfed, arid and semi-arid climate.

Passive dew collection could be a viable option as a source of irrigation water in arid areas. The plastic foil acting as a condensing surface plays a key role in the passive dew collection regime. A laboratory method for comparing various plastic foils for dew collection was prepared and tested. The focus was on creating a method for measuring the attributes affecting dew condensation and the flow of dew droplets on the measured surface. A low-density polyethylene foil designed for dew collection, white polyethylene plastic, black polyethylene plastic, and white polyvinyl chloride plastic were used as the test plastics. The laboratory dew yields were compared with model calculations. In addition, field trials were conducted in arid conditions in Maktau, Kenya, to compare with the laboratory measurement. Results from the hardware model tests were not reflected in the results obtained from the field conditions. The laboratory tests showed that the dew-harvesting quality of plastic foils is difficult to evaluate using the laboratory test rig. A more comprehensive evaluation regime requires tests performed in field conditions or further development of the test rig used here. • A hardware model was constructed for testing plastic foils for dew collection. • Dew was harvested in controlled laboratory conditions and in arid field conditions. • No clear similarity was found between results in field and laboratory conditions. [ABSTRACT FROM AUTHOR]

Summary: To extend the reach of cloud computing, the concept of edge computing and dew computing is introduced to execute various Internet of things (IoT) application with minimized delay in real time. The requested tasks are allocated computing resources that best suits their purpose. In this work, a novel hybrid hierarchical dew based edge to cloud architecture is developed. The objective of the study is to provide a detailed analysis and validation of real‐time scheduling of IoT application in this hybrid hierarchical ecosystem. The problem of optimally mapping requested tasks to the computing layers is mathematically formulated based on several quality of service factors and solved using the proposed hybrid adaptive metaheuristic algorithm. This is a combination of learning‐based adaptive particle swarm optimization and genetic algorithm. The exploitative and exploratory feature of the proposed algorithm helps in achieving better global optima compared with other existing metaheuristic algorithms. [ABSTRACT FROM AUTHOR]

Natural disasters like bushfires pose a catastrophic threat to the Australia and the world's territorial areas. This fire spreads in a wide area within seconds, and therefore, it is complicated and challenging to mitigate. To minimize risk and increase resilience, identifying bushfire occurrences beforehand and takes necessary actions is critically important. This study focuses on using deep learning technology for predicting bushfire occurrences using real weather data in any given location. Real-time and off-line weather data was collected using Weather Underground API, from 2012 to 2017 ( N = 128 , 329 ). The obtained weather data are temperature, dew point, pressure, wind speed, wind direction, humidity, and daily rain. An algorithm was developed to collect this data automatically from any destination. Six different optimizer models were analyzed that use in deep learning technology. Then, the comparison was carried out to identify the best model. Selecting an optimizer for training the neural network, in this case, deep learning is a challenging task. Six best optimizers were chosen to compare and identify the best optimizer to estimate potential fire occurrences in given locations. The six optimizers; Adagrad, Adadelta, RMSprop, Adam, Nadam, and SGD were compared based on their processing time, prediction accuracy and error. Our findings suggest Adagrad optimizer provides less prediction time which is a critical factor for fast-spreading bushfires. Our work provides a data collection model for disaster prediction, which could be utilized to collect climatic characteristics and topographical characteristics in with larger samples. The developed methodology could be utilized as a natural disaster prediction model for precise predictions with less error and processing time using real-time data. This study provides an enhanced understanding of finding the locations that fire starts or spot fires which are more likely to occur, and lead to identifying of fire starts that are more likely to spread. [ABSTRACT FROM AUTHOR]

In this paper, we proposed a theoretical model to study the dispersion of hydrogen. The model given a correlation between the concentration and temperature for cryogenic gases. The model based on adiabatic mixing hypothesis and neglected exterior heat sources, and thought the gas mixture was always at quasi-steady state. Real-gas law was adopted, and thermal physical properties of the gases are obtained from NIST REFPROP database. The concentration curve approximately appears a decreasing straight line, and turns on dew point and ice point, since heat released from water vapor phase change. Compared with liquid hydrogen and liquid natural gas spill experimental data, the model obtained well agreement solutions. Effects of three typical weather conditions (atmospheric temperature, relative humidity and barometric pressure) on hydrogen dispersion were quantitatively studied. It is confirmed that the dispersion is excited in summer, and is depressed in winter and transition seasons with increased ambient temperature. With increased ambient temperature, the effect of increased enthalpy reduction of the dry air components and the effect of the water latent heat are respectively dominate in the 268.15–293.15 K and 293.15–308.15 K ranges. Compared to ambient temperature and barometric pressure, relative humidity has the strongest positive effect on hydrogen dispersion, and the slight dampening effect of barometric pressure could be neglected. • A theoretical model on the correlation of concentration with temperature was built. • A larger gradient of the declining concentration curve means faster dispersion. • Effects of three typical weather conditions on hydrogen dispersion were studied. • Water vapor plays an important role during hydrogen dispersion process. [ABSTRACT FROM AUTHOR]

It is widely accepted that the atmospheric boundary layer is drastically under-sampled in the vertical dimension. In recent years, the commercial availability of ground-based remote sensors combined with the widespread use of small, weather-sensing uncrewed aerial systems (WxUAS) has opened up many opportunities to fill this measurement gap. In July 2018, the University of Oklahoma (OU) deployed a state-of-the-art WxUAS, dubbed the CopterSonde, and the Collaborative Lower Atmospheric Mobile Profiling System (CLAMPS) in the San Luis Valley in south-central Colorado. Additionally, these systems were deployed to the Kessler Atmospheric and Ecological Field Station (KAEFS) in October 2018. The colocation of these various systems provided ample opportunity to compare and contrast kinematic and thermodynamic observations from different methodologies of boundary layer profiling, namely WxUAS, remote sensing, and the traditional in situ radiosonde. In this study, temperature, dew point temperature, wind speed, and wind direction from these platforms are compared statistically with data from the two campaigns. Moreover, we present select instances from the dataset to highlight differences between the measurement techniques. This analysis highlights strengths and weaknesses of planetary boundary layer profiling and helps lay the groundwork for developing highly adaptable systems that integrate remote and in situ profiling techniques. [ABSTRACT FROM AUTHOR]

The efficient utilization of renewable energy sources should rely on the exploitation of a mix of thermal and electric energy rather than relying on a single energy source. One way to apply this shared generation concept to space heating/cooling and refrigeration in both residential and industrial sector is through hybrid sorption-compression chillers. However, the experience on these systems is still limited and therefore their design and optimization require some efforts. Starting from the experimental experience on the testing of different hybrid cascade chillers, and integrating the measurement with a dynamic model, some considerations on the sizing, design and optimization of hybrid thermal-electric chillers are reported. In particular, design conditions of pre-commercial or commercial systems are evaluated and optimization at different levels is proposed, i.e. on the core components (through the proper design of relative capacities of the units in the cascade and through proper selection of the refrigerant), on the auxiliaries, to reduce their electricity consumption, and on the overall management of the hybrid chiller. Results demonstrated that the higher is the operating temperature lift between evaporator and condenser the higher are the achievable energy savings of a cascade chiller. • Experimental and numerical experience for the critical analysis of cascade chillers. • Improvements on components, auxiliaries and control are suggested. • Optimal design include the selection of the refrigerant of the compression unit. • The control and management strategies are essential for proper integration of units. [ABSTRACT FROM AUTHOR]

A large amount of data, called the big data, generated by the devices that are part of the Internet of Things, is expected in the coming years. This scenario creates challenges for sending, processing, and storing all data centrally in the cloud. Recent works propose a decentralization of the processing and storage of this data in local devices close to the user to solve such challenges. This paradigm, called dew computing, has been gaining attention from academia. Several works apply this proposal through devices such as desktops, laptops, and smartphones. However, after a systematic review, no studies were found that applied this proposal to smart wearable devices. Thus, this work shows the research, evaluation, analysis, and discussion of smartwatches for the dew computing environment. The results of this work showed that smartwatches could extend local device functionalities through performing services, cooperating with decentralizing cloud computing, and helping to reduce the negative impacts of the big data. [ABSTRACT FROM AUTHOR]

This study aims to assess an air-conditioning cycle designed to make use of hydrofluoroolefins (HFOs) within a direct expansion air-conditioning system combined with a solar energy source. An energy–exergy analysis was applied in order (i) to examine which HFO working fluid is more efficient and (ii) to draw a comparative analysis between the proposed cycle and the conventional air-conditioning cycle. To achieve this, a simulation has been devised to determine the coefficient of performance (COP), exergetic efficiency, and total irreversibility for three HFOs. These HFO fluids are R1234yf, R1234ze(E), and R1233zd(E) which were compared to R410A and R134a. System operating conditions, such as the impact of storage tank exit temperatures on compressor discharge temperatures and condenser surface augmentation, were also taken into consideration and are being investigated. Results of the study indicated that the use of evacuated tube solar collector within a vapor compression air-conditioning system can improve performance by 15–56% and save 5–40% in electrical energy consumption. The study also concludes that HFOs are excellent alternatives for R410A and R134a. Accordingly, the total irreversibility of the proposed cycle with R1234yf, R1234ze(E) and R1233zd(E) is less than that of R410A and R134a. [ABSTRACT FROM AUTHOR]

A comparative study between two solutions which they usually work as a working pairs in pumpless absorption cooling system is achieved analytically with aid of ESS (Engineering Equation Solver) 9.43 software. The pump in this system is replaced by a vertical pipe (lift tube) to ensure the pressure difference between the condenser and the evaporator. These working pairs are Lithium Bromide-Water and Lithium Chloride-Water. The study intends Iraqi summer weather as an ambient circumstances. A thermodynamics model is designed to find the energy and Energy loss in each of system components. By solving the thermodynamic model, and assuming the same generator, absorber, condenser and evaporator temperatures in each case. It's found that the system coefficient of performance is relatively the same while the probability of agglomeration in case of Lithium Bromide-Water system is higher because of the large salt concentration. It's concluded that the Lithium Chloride- Water is most suitable in Iraqi circumstances in spite of high values of total energy loss which is obtained in case of Lithium Chloride-Water system if it is compared with the energy loss value in case of Lithium Bromide-Water system. [ABSTRACT FROM AUTHOR]

Intense sub‐daily summer rainfall is linked to flooding impacts in the United Kingdom. Characterizing the atmospheric conditions prior to the rainfall event can improve understanding of the large‐scale mechanisms involved. The most intense sub‐daily rainfall intensity data generated from rain gauge records across the United Kingdom over the period 1979–2014 are combined with fields from the ERA Interim reanalysis to characterize atmospheric conditions prior to heavy rainfall events. The 200 most intense 3‐hourly events for six UK regions are associated with negative anomalies in sea level pressure (<−2 hPa) and 200 hPa geopotential height (<−60 m) to the west or south west of the United Kingdom 1 day earlier, with above average moisture, evaporation and dew point temperature over North West Europe. Atmospheric precursors are more intense but less coherent between regions for composites formed of the 25 heaviest rainfall events but all display substantial moisture transport from the south or south east prior to their occurrence. Composites for the heaviest events are characterized by a tripole geopotential anomaly pattern across the North Atlantic. Above average geopotential height and dew point temperature over Newfoundland and below average geopotential height but elevated evaporation in the North Atlantic are found to be weakly associated with an increased chance of the most intense sub‐daily rainfall events 5–9 days later. [ABSTRACT FROM AUTHOR]

While the large-scale deployment of photovoltaics (PV) for generating electricity plays an important role to mitigate global warming, the variability of PV output power poses challenges in grid management. Typically, the PV output power is dependent on various meteorological variables at the PV site. In this paper, we present a systematic approach to perform an analysis on different meteorological variables, namely temperature, dew point temperature, relative humidity, visibility, air pressure, wind speed, cloud cover, wind bearing and precipitation, and assess their impact on PV output power estimation. The study uses three years of input meteorological data and PV output power data from multiple prosumers in two case studies, one in the U.S. and one in the Netherlands. The analysis covers the correlation and interdependence among the meteorological variables. Then, by using machine learning-based regression methods, we identify the primary meteorological variables for PV output power estimation. Finally, the paper concludes that the impact of using a lower-dimensional subspace of meteorological variables per location, as input for the regression methods, results in a similar estimation accuracy in the two case studies. • An analysis of the correlation and interdependence of 9 different meteorological variables in two case studies. • A dimensionality reduction of the input meteorological variables is presented. • Several machine learning regression methods are evaluated for estimating PV output power. • The importance and ranking of the variables depend on the climate of the area of study. • A lower-dimension subspace of meteorological variables can result in a slightly similar estimation accuracy. [ABSTRACT FROM AUTHOR]

In this study, a novel Ocean Thermal Energy Conversion (OTEC) based tri-generation system that produces ammonia, cooling and power is developed and analysed. This OTEC plant operates on the naturally existing temperature difference that exists in various depths of the ocean. The OTEC plant used in this study is operated using a single-stage ammonia Rankine cycle. The discharge seawater from the condenser in the organic Rankine cycle is used to provide district cooling. Two different operation cases of the analysed system are considered, where for the first case 50% of the power produced is stored in the form of ammonia during the off-peak hours. The second case is for complete power production proposed for peak hours. For the case where 50% of the power produced (case 1) is used to produce ammonia the highest energy and exergy efficiency is found to be 1.37% and 56.17% respectively. As for the case where, only power is produced (case 2) the maximum energy and exergy efficiency of the OTEC plant is found to be 1.83% and 78.02% respectively. The corresponding maximum power production was 6612 kW and 13,224 kW for cases 1 and 2. The maximum hydrogen and ammonia production rate is found to be 94.35 kg/h and 534.7 kg/h at peak efficiency values. The cooling duty at the peak energy and exergy efficiency is found to be 64.4 MW where the condenser temperature is 11.38 °C. • A comprehensive study for the cooling duty associated with OTEC is performed. • Energy and exergy efficiencies of the system are found to be 1.37% and 56.17% (Case 1). • Energy and exergy efficiencies of the system are found to be 1.83% and 78.02% (Case 2). • The maximum hydrogen and ammonia production rates are 94.35 kg/h and 534.7 kg/h. [ABSTRACT FROM AUTHOR]

Foliar water uptake (FWU) has been reported for different species across several ecosystems types. However, little attention has been given to arid ecosystems, where FWU during dew formation or small rain events could ameliorate water deficits. FWU and their effects on leaf water potential (ΨLeaf) were evaluated in grasses and shrubs exploring different soil water sources in a Patagonian steppe. Also, seasonal variability in FWU and the role of cell wall elasticity in determining the effects on ΨLeaf were assessed. Eleven small rain events (< 8 mm) and 45 days with dew formation were recorded during the study period. All species exhibited FWU after experimental wetting. There was a large variability in FWU across species, from 0.04 mmol m−2 s−1 in species with deep roots to 0.75 mmol m−2 s−1 in species with shallow roots. Species-specific mean FWU rates were positively correlated with mean transpiration rates. The increase in ΨLeaf after leaf wetting varied between 0.65 MPa and 1.67 MPa across species and seasons. The effects of FWU on ΨLeaf were inversely correlated with cell wall elasticity. FWU integrated over both seasons varied between 28 mol m−2 in species with deep roots to 361 mol m−2 in species with shallow roots. Taking into account the percentage of coverage of each species, accumulated FWU represented 1.6% of the total annual transpiration of grasses and shrubs in this ecosystem. Despite this low FWU integrated over time compared to transpiration, wetting leaves surfaces can help to avoid larger water deficit during the dry season. [ABSTRACT FROM AUTHOR]

The potential of different models – deep echo state network (DeepESN), extreme learning machine (ELM), extra tree (ET), and regression tree (RT) – in estimating dew point temperature by using meteorological variables is investigated. The variables consist of daily records of average air temperature, atmospheric pressure, relative humidity, wind speed, solar radiation, and dew point temperature (Tdew) from Seoul and Incheon stations, Republic of Korea. Evaluation of the model performance shows that the models with five and three-input variables yielded better accuracy than the other models in these two stations, respectively. In terms of root-mean-square error, there was significant increase in accuracy when using the DeepESN model compared to the ELM (18%), ET (58%), and RT (64%) models at Seoul station and the ELM (12%), ET (23%), and RT (49%) models at Incheon. The results show that the proposed DeepESN model performed better than the other models in forecasting Tdew values. [ABSTRACT FROM AUTHOR]

During four growing seasons (2013–2017), 282 leaf rust progress curves were characterized across experimental plots according to a number of climate-crop-disease variables in Kermanshah province, Iran. Leaf rust severity differed significantly between levels of cultivar, planting date, sampling time and year factors. Area under disease progress curve (AUDPC) based on disease severity was ranked using Kruskal–Wallis one-way ANOVA. H-test comparison between two disease-onset levels indicated lower mean AUDPC value for late disease onset than that for early disease onset. Highest and lowest AUDPC values were obtained in spring 2016 and 2015, respectively. According to principal component analysis, three principal components accounting for 73% of data variance verified dependence of leaf rust intensity on air temperature and wetness, cultivar resistance, date of disease onset, wheat maturity, and planting date. Based on principal component regression model, disease-onset and maturity date, mean 6-monthly temperature, number of days with minimum temperatures within the range of 5–25 °C and maximum RH > 60%, resistance index, and planting date justified 74% of variability in AUDPC dataset. These findings recommend involvement of cultivar resistance, dates of wheat maturity and planting along with weather predictors in wheat-leaf-rust studies to increase prediction value of future models, durability of host resistance to disease, and sustainability of disease control methods. [ABSTRACT FROM AUTHOR]