Amount Of Water Loss Research Articles

Identifying the Optimal Water-Occluding Earplugs: A Scientific Simulation Study.

Numerous types of water-occluding earplugs are available as a means of preventing infection in patients with external and middle ear disease. However, little is known about the comparative efficacies of these earplugs with prolonged water exposure. In this study, we assessed the water impermeability of various earplug materials to prolonged water exposure. Nine earplugs were tested: cotton wool mixed with petroleum jelly, cotton wool externally coated with petroleum jelly, Blu-Tack, foam earplugs, silicone putty, silicone earplugs, flanged earplugs, and hard and soft silicone custom-moulds. Precision-engineered cups were filled with 30 mL water and sealed with lids that contained a 10 mm diameter hole to simulate the ear canal. The aperture was occluded with different earplugs, and the cup was inverted. Computer software was used to record the water loss to the nearest 10 milligrams 720 times over a three-hour period. The test was repeated five times for each material. The water permeability onset, rate, and total amount of water loss varied markedly between the materials; cotton wool mixed with petroleum jelly demonstrated the fastest onset of leak and the highest rate of water loss (p < 0.00001), as well as the largest amount of cumulative water loss (p = 0.00213). The soft silicone custom-mould plugs, hard silicone custom-mould plugs, foam plugs, and silicone putty demonstrated no leaks. This study demonstrates a wide range of water permeabilities of commonly used ear-occluding materials during prolonged water exposure. We found that the generally suggested regimen of cotton wool mixed with petroleum jelly may be inefficacious for substantial periods of water exposure.

Biomass changes registered in two Sedum species under ecological stress conditions

Sedum plants are considered to be appropriate for green roof landscape designs because of their resistance to draught. The purpose of these experiments ware to identify the extent of drought conditions on development of plants. Observations were made to measure the amount of water loss per day on plants exposed for 8 days to high temperatures and drought. The experiment was conducted in 2014 at the Floriculture greenhouse at UASMV Cluj-Napoca, using S. reflexum sand S. spectabile stalks plants. The results pointed different responses of the two analyzed species regarding the partial and the cumulative differences reported to the initial weight of the plants. Diagrams representing cumulative weight loss over time show uniformity on both charts, even that Sedum reflexum plants lose greater amounts of water than those of Sedum spectabile. Also, at S. spectabile plants, the water loss affected all the leaves.

Water balance attributes for off-host survival in larvae of the winter tick (Dermacentor albipictus; Acari: Ixodidae) from wild moose

ABSTRACTTo explore how the one-host tick Dermacentor albipictus survives off-host, we determined water balance characteristics of eggs and larvae. In contrast to eggs, larvae lost water fast, absorbed water vapour and died from a low amount of water loss. Placing mated females under near water-saturated conditions yielded larvae that absorbed and survived only at high relative humidities. We observed larvae forming clusters. Water loss rate of larvae decreased as group size increased. In response to day length, larvae lost water slower under long day than short day conditions. Larvae could switch quickly between fast water loss rate (short day) and slow water loss rate (long day) within a day, independent of the photoperiodic experience of the egg or mother. Long day exposure had no effect on water relations, incubation and survival of eggs. We conclude that eggs are modified for water conservation. Larvae survive by having a water balance maternal effect; i.e. capacity for water vapour absorption in the larva is determined by the relative humidity experienced by the mother. Larvae regulate water loss behaviourally through larval clustering and summer quiescence. Understanding these water balance attributes and effects of desiccation on egg and larval survival during summer are important to better predict the potential population impacts of winter ticks on moose.

The benefits of recycling: how photosynthetic bark can increase drought tolerance.

[Extract] Understanding the drought physiology of woody plants has become an increasingly important focus of plant science research in recent years, spurred on by concern about the potential for widespread tree mortality in response to drought stress caused by global warming (McDowell et al., 2008; Allen et al., 2010). However, there is one aspect of how woody plants cope with water deficits that has received very little attention: the role of carbon fixation by photosynthetic bark. This process may become especially important for maintaining physiological activity in woody tissues of drought-stressed trees as the supply of photosynthate from leaves dwindles, due to stomatal closure and impaired phloem translocation. In this issue of New Phytologist, Vandegehuchte et al. (pp. 998–1002) bring this process into the spotlight, and provide a compelling argument for why we should take more notice of that often-hidden, green layer of tissue that is ubiquitous beneath the smooth-bark surfaces of woody plants (Scott, 1907; Pfanz et al., 2002; Dima et al., 2006; Rosell et al., 2015).

Use of FTIR combined with forms of water to study the changes in hydrogen bonds during low-temperature heating of lignite

ABSTRACTThe changes in the hydrogen bonds (HBs) of three types of Indonesian lignite during low-temperature heating were investigated. The amount of water loss was determined by weighing the samples before and after heating in an oven. The changes in the number of the different types of HBs were determined using Fourier transform infrared spectroscopy coupled with types of water in lignite. The number of peak positions and absorption bands in each spectrum was determined by curve-fitting analysis with a Gaussian function. The quantified integrated area of aromatic hydrogen atoms was used to accurately investigate the changes in the HBs. The results show that at low temperatures (T ≤ 50°C), free water is mainly removed, and the HBs broken are those between free water molecules. However, at medium temperatures (50 <T ≤ 100°C), bound water is mainly removed. The number of HBs significantly changes because of the breaking of bound water molecule HBs and bound water cluster–carboxyl group HBs, and the formation of nonfreezable moisture HBs. At high temperatures (100 <T < 125°C), nonfreezable moisture can be released. The number of HBs changes as a result of competition between the removal of nonfreezable moisture and the increase in the number of carboxyl groups. At higher temperatures (T ≥ 125°C), the moisture remaining in lignite is thermal decomposition moisture. In addition, the rate of decomposition of carboxyl groups is higher than the rate of generation, which means that the number of HBs markedly decreases at higher temperatures.

Evaluation of combined effects of ageing period and freezing rate on quality attributes of beef loins

The objective of our study was to evaluate the combined effects of ageing period and different freezing rates on meat quality attributes of beef loins. Pairs of loins (M. longissimus at 1day post mortem) from 12 carcasses were divided into four equal portions and randomly assigned to four ageing/freezing treatments (aged only, frozen only, and 3 or 4weeks ageing at −1.5°C then frozen). Two freezing methods (fast freezing by calcium chloride immersion or slow freezing by air freezer at −18°C) were applied to the loin sections. Fast freezing had no effect on shear force (P>0.05), but significantly improved the water-holding capacity of the aged/frozen loins by reducing purge and drip losses. Ageing-then-freezing significantly improved shear force values of loins compared to both the aged only and frozen only loins. These observations suggest that fast freezing will add more value to the aged/frozen/thawed meat by minimising the amount of water-loss due to the freezing/thawing process.

Quantitative assessment of the impacts of irrigation on surface water fluxes in the Tarim River, China

Irrigation is a significant human activity that affects surface water fluxes in the Tarim River Basin. To quantitatively assess the irrigation impact of this activity on surface water fluxes in the Tarim River, a land surface hydrologic model was coupled with a modified irrigation scheme and a reservoir module and applied to simulate these fluxes. Modeling results indicate that the combined effect of the irrigation process and reservoir operation is prominent in the study area, from which 70–75% of the surface water is extracted and used for irrigation. This scenario can primarily be attributed to the significant amount of water losses as a result of evaporation and the seepage of canals and aqueducts. The effective utilization coefficient of the extracted surface water is only approximately 0.40. The irrigation water withdrawals increased with the recent rapid expansion of cultivated land. Therefore, the water flowing into the main stem of the Tarim River still shows a downward trend, despite the significant increase in the total discharge of headwater basins since the 1960s.

Bilateral virtual water trade in agricultural products: a case study of Germany and China

Most studies in the field of virtual water trade concentrate either on the global, national or sub-national level, or on the water footprint of individual products. This article assesses the virtual water trade in agricultural products between Germany and China during the period 2008–2010. Germany exported 192 million m3 of virtual water to China and imported 801 million m3 from China. Through the bilateral trade, Germany saved 69.8 million m3 water, while China had a net water loss of 469.4 million m3. Thus, the global water loss amounts to 399.6 million m3.

Effort in reducing unaccountable water and economic consideration

In 2007, Maynilad Water Services, Inc. (Maynilad), the private water and wastewater service provider of the West Zone of Metro-Manila (Philippines), had an enormous challenge ahead: to achieve 100% service coverage in the coming few years with basically no additional water resources; to connect an additional 3 million people still without access to piped water; and to improve the service level to the existing customers. The only way to meet this demand is to reduce water losses from its deteriorated pipe network. Water balance made in that year showed significant total non-revenue water of 1,500 million liters per day which is equivalent to 66% of the total system input volume. Maynilad recognized that to be financially viable, it needs to address the non-revenue water problem. Thus, the Central NRW team was immediately created in 2008 and was tasked to lead Maynilad's ambitious NRW reduction and management program, which is considered one of the largest NRW projects in the world in terms of amount of water losses and the scope and magnitude of works involved to bring down the high level of NRW. Maynilad's NRW program involves breaking up the whole network into hydraulically isolated and measurable district metered areas (DMA); monitoring and diagnosing each DMA; developing well-trained and fully equipped leak detection teams to find surfacing and non-surfacing leaks; active leakage control; pressure management; selective pipe replacement/rehabilitation; closing of illegal connections and decommissioning of old distribution pipes; integrated meter management; and a sustained capacity building of NRW teams. By the end of 2013, 6 years after implementing the NRW program, Maynilad was able to recover more than 700 MLD and managed to bring down the NRW level to 39%. The water that was saved in turn was used to supply additional 400,000 new customers in the expansion areas and generally improved the level of service of the existing customers by providing higher water pressure and longer water availability. These translated to an increase in billed volume by 56 and 107% increase in total revenues for the company.

Comparison of cucumber and watermelon yield and water use in clay pitcher and furrow irrigation methods

The field experiments were conducted to quantify the influence of furrow and clay pitcher irrigation methods on crop water productivity (CWP) and fruit yield of cucumber and watermelon crops in Yazd region in Central Iran. The comparison of the CWP of cucumber and watermelon indicates that in clay pitcher irrigation the value of CWP is 4.91 and 4.79 times as big as the furrow irrigation, respectively. The cucumber fruit harvesting stage was 49 days from June 2nd to July 20th. Total fruit yield was 2.5 kg per plant for pitcher irrigation and 2.04 kg per plant for furrow irrigation. The watermelon fruit harvesting stage was 55 days from 16 June to 10 August. Total fruit yield was 8.61 kg per plant for pitcher irrigation and 7.86 kg per plant for furrow irrigation. The results indicate that traditional pitcher method can prevent huge amount of water losses, especially in arid and semi-arid regions of the world.

Comparison the properties of PVA/Na+‐MMT nanocomposite hydrogels prepared by physical and physicochemical crosslinking

A novel physicochemical crosslinked nanocomposite hydrogel based on polyvinyl alcohol (PVA) and natural Na‐montmorillonite (Na+‐MMT) was synthesized by chemical crosslinking of nanocomposite hydrogel followed by a freezing‐thawing process. The effects of physical crosslinking, as well as physicochemical crosslinking, on the structure, morphology, and properties (thermal, mechanical, swelling, and deswelling) of nanocomposite hydrogels were investigated and compared with each other. The structure and morphology of nanocomposites were studied by Fourier transform infrared, X‐ray diffraction, field emission scanning electron microscopy, and transmission electron microscopy techniques. The thermal and mechanical properties of nanocomposites that were affected by physical and physicochemical crosslinking were evaluated by thermogravimetric analysis, differential scanning calorimeter, dynamic mechanical analysis, hardness test, and Water vapor transmission rate (WVTR) experiments. The results showed that the physicochemical crosslinking of a PVA nanocomposite leads to a reduction in crystallinity and melting temperature, as well as an increase in the Hardness and WVTR compared to a physically crosslinked PVA nanocomposite hydrogel. The swelling and deswelling experiments were performed using a gravimetric method, and it was shown that controlled crosslinking of PVA nanocomposite hydrogel with glutaraldehyde causes the swelling ratio to increase and the cumulative amount of water loss to decrease. The swelling (sorption) and deswelling (desorption) kinetics data for physically and physicochemical crosslinking of nanocomposite hydrogels were fitted with a fickian model. It is concluded that through control crosslinking of PVA nanocomposite can lead to a hydrogel with higher swelling capacity than that is in conventional PVA nanocomposite hydrogel. POLYM. COMPOS., 37:897–906, 2016. © 2014 Society of Plastics Engineers

A longitudinal study of skin barrier function in pregnancy and the postnatal period.

It is unknown whether skin's barrier function changes in pregnancy. Trans Epidermal Water Loss (TEWL) refers to the total amount of water loss through the skin and TEWL can be measured non-invasively as an index of skin barrier function. We measured TEWL during and after pregnancy to evaluate pregnancy-related skin barrier function. This was a prospective, longitudinal cohort study of 52 low-risk, first-time pregnant women nested within the Screening for Pregnancy Endpoints (SCOPE) Ireland study. TEWL (gwater/m2/h) was measured three times during pregnancy: 19-21 weeks, 27-32 weeks and 36 weeks; and three times postnatally: 2-4 days, 2 months and 6 months post-delivery. Data were analysed using SPSS 18.0 and P > 0.05 was considered statistically significant. A rise in TEWL was seen between each visit with the highest readings, exceeding the normal range of 0-20 gwater/m(2)/h, recorded at two months post-delivery. Forty women attended at two months post-delivery of whom 22 women had an average reading between 0 and 20 gwater/m(2)/h; 10 women had an average reading between 21 and 40 gwater/m(2)/h and 8 women had an average reading between 41 and 75 gwater/m(2)/h. Readings had returned to an average of 0-20 gwater/m(2)/h at six months postnatally. TEWL increases slightly in pregnancy and the postnatal period. The clinical significance of this is unclear and requires further investigation.

Insensible water loss through adult extracorporeal membrane oxygenation circuit: an in vitro study.

Patients on extracorporeal membrane oxygenation (ECMO) are critically ill, and fluid balance need to be managed as accurately as possible. Previous studies have focused on insensible water loss through neonatal ECMO circuit and showed that water loss through the ECMO circuit was correlated with the sweep-gas flow rates. Current study is the first study focusing on insensible water loss through adult ECMO circuit. An in vitro extracorporeal circuit consisting of Jostra Quadrox D membrane oxygenator and centrifugal pump was primed with normal saline. The amount of water loss through the ECMO circuit was found to be linearly correlated with the sweep-gas flow rate and fluid temperature. For every liter per minute of sweep-gas flow at 37°C, 0.046 ml/min of water will be lost, and for every change of fluid temperature by 1°C, water content loss will be changed by 0.0026 ml/min by multiple linear regression (R = 0.996). The average daily water loss for every liter per minute of sweep-gas flow at 33, 34, 35, 36, 37, 38, and 39°C were 51.3, 55, 58.8, 62.5, 66.2, 70.0, and 73.7 ml/day, respectively.

The effect of packaging material and storage period on microwave-dried potato (Solanum tuberosum L.) cubes.

The effect of three packaging materials (transparent biaxially oriented polypropylene laminate (BOPP); semi-transparent BOPP; polyethylene-polyamide (PE-PA) laminate) in three packaging conditions (vacuum, N2, natural atmosphere) and in two temperature treatments (blanching in hot water; steam) on microwave-dried potato (Solanum tuberosum L.; Solanaceae) cubes was studied. After storage for 60 and 120days, the amount of ascorbic acid (AA), shrinkage and rehydration were determined. Dried potato cubes packaged under N2 atmosphere had the highest rehydration value (3.142%). Since there is a direct relationship between the amount of water loss and shrinkage, samples packaged in PE-PA laminate packages under vacuum showed 4.947% less shrinkage than transparent BOPP or semi-transparent BOPP due to low permeability of these packages. Potatoes stored for 120days resulted in 7.89% more shrinkage than those stored for 60days. The least loss in AA occurred in PE-PA laminate packaging. The shelf-life of potato cubes can be increased and their quantitative and qualitative characteristics can be best preserved by package-drying in PE-PA laminate under vacuum conditions.

A rapid dehydration leaf assay reveals stomatal response differences in grapevine genotypes.

A simple and reliable way of phenotyping plant responses to dehydration was developed. Fully-developed leaves were detached and placed in a closed plastic box containing a salt solution to control the atmospheric water potential in the container. Three hours of dehydration (weight loss of the leaf) was optimal for measuring changes in stomatal response to dehydration. Application of the plant hormone abscisic acid (ABA) prior to leaf detachment decreased the amount of water loss, indicating that the assay was able to detect differences based on a stomatal response to dehydration. Five different Vitis genotypes (V. riparia, V. champinii, V. vinifera cv. Shiraz, V. vinifera cv. Grenache and V. vinifera cv. Cabernet Sauvignon) with known differences in drought tolerance were screened for their dehydration response and the results obtained corresponded to previous reports of stomatal responses in the vineyard. Significant differences in stomatal density along with differences in the amount and rate of water lost indicate differences in dehydration sensitivity among the genotypes screened. Differences in stomatal response to ABA were also detected. Shiraz had the lowest stomatal density and the highest ABA sensitivity among the genotypes screened, yet Shiraz lost the most amount of water, indicating that it was the least sensitive to dehydration. Despite having the highest stomatal density and intermediate stomatal sensitivity to ABA, V. riparia lost the smallest amount of water, indicating that it was the most sensitive to dehydration. The assay presented here represents a simple and reliable phenotyping method for plant responses to leaf dehydration.

Shrivel development in kiwifruit

Shrivel is a potential storage quality problem for kiwifruit. ‘Zesy003’ (commonly called Gold9) is a newly released, yellow-fleshed Actinidia chinensis cultivar that tends to shrivel more than other commercialised cultivars. Water loss and shrivel in Gold9 fruit were investigated during storage at 1°C for up to 14 weeks and shelf-life at 20°C. In addition, the water status of ripe fruit was quantified by magnetic resonance imaging and the capacity of a crude outer pericarp cell wall extract to swell. Shrivelled Gold9 fruit had 1–6% weight loss, although 6% weight loss did not always result in shrivel. Three weeks of storage resulted in fruit taking longer to shrivel during shelf-life, with a concomitant higher weight loss by the time the fruit was shrivelled. In contrast, 14 weeks of storage resulted in fruit that shrivelled more rapidly in shelf-life at a lower weight loss. At any given time after harvest, fruit with more severe shrivel tended to be softer than less shrivelled fruit. Shrivel therefore appears associated with fruit softening. Outer pericarp tissue from ripe Gold9 fruit had lower water mobility and a greater capacity to swell than pericarp from other kiwifruit cultivars. It is concluded that shrivel is not determined simply by an absolute amount of water loss. The development and ease of expression of shrivel in Gold9, and possibly other kiwifruit, is influenced by softening and the water characteristics of the fruit outer pericarp when soft.

IRRIGATION AND CLIMATE ZONE TRIALS OF PERENNIAL PLANTS FOR SUSTAINABLE LANDSCAPES

Unstable water supplies in the Western U.S. have become more uncertain due to increasingly drier winters and rising urban populations, and chemical laden runoff from over-watered urban landscapes threatens the health of waters that receive the runoff. In California, this has led to regulations on landscape planning and installation that require knowledge of plant water requirements and the use of water-conserving plants to balance turf water needs. However, there is very little research-based data on the water use of landscape plant species. To address these issues, 2-year irrigation and climate zone trials were begun in 2005, 2007, 2009, and 2011 on landscape perennials considered by the University of California Davis Arboretum to be water-conserving, pest tolerant, and disease resistant. In each trial, ten species were evaluated on 4 levels of irrigation based on reference evapotranspiration (ET0), the estimated amount of water loss from a reference crop. Six replicates of each species and treatment were planted and established on regular irrigation (80% of ET0) the first year. The following May through October they received an irrigation treatment at 20, 40, 60, or 80% of ET0. Monthly measurements and qualitative evaluations were made to assess differences between treatments. Many of the same plants were also placed in demonstration gardens in different climate zones across California where UC Master Gardeners evaluated their performance. In many cases, there were no significant differences between irrigation treatments in either plant growth or quality, while a few species showed slight differences in one or both areas. The plant water use data being generated in these trials is helping support the necessary transition to sustainable gardens in summer-dry Mediterranean climates.

Decreasing of water loss and mud cake thickness by CMC nanoparticles in mud drilling

CMC polymer is used as an additive to decrease water loss and mud-cake-thickness in mud drilling. In this study, the effect of CMC and CMC nanoparticles on water loss and mud-cake-thickness in mud drilling is investigated. CMC nanoparticles are made by using of ball milling and their size is measured by Particle size analyzer. CMC and CMC nanoparticles which were prepared by Hamilton batch mixer and with certain percent suggested by API, were added to the water-based mud drilling. The amount of water loss and mud cake thickness was measured by filter press. It was found that adding CMC nanoparticles in comparison with conventional CMC resulted in desirable reduction of amount of water loss and mud cake thickness.

Water loss from flower heads predicts seed release in two invasive thistles

Background : Non-random seed release caused by plant responses to weather conditions is important for seed dispersal. Much is known about the effects of wind speed and turbulence, but our understanding of the effects of water loss on seed release is either qualitative, or indirect and phenomenological. Aims : To quantify the empirical relationship between water loss and seed release. Methods : Capitula of the invasive thistles Carduus acanthoides and C. nutans were collected from the field and treated for either 0, 1 or 2 days in the laboratory at three different vapour pressure deficit levels (3.4, 9.5 and 17.0 hPa) to cause a range of water loss values. Total seed release was quantified before and during wind tunnel trials. Results : Water loss was the only significant predictor of whether or not capitula released any seeds. The number of seeds released was predicted by water loss, capitulum diameter and herbivore damage, with the same amount of water loss having less effect on larger capitula. Conclusions : These results represent an important step towards using weather data to predict seed release for many xerochastic species. Incorporating the effects of water loss on seed release into mechanistic seed dispersal models will greatly improve predictions of when and how far seeds disperse.

Management of heat in laser tissue welding using NIR cover window material

Laser tissue welding (LTW) is a novel method of surgical wound closure by the use of laser radiation to induce fusion of the biological tissues. Molecular dynamics associated with LTW is a result of thermal and non-thermal mechanisms. This research focuses exclusively on better heat management to reduce thermal damage of tissues in LTW using a near infrared laser radiation. An infrared continuous-wave (CW) laser radiation at 1,450 nm wavelength corresponding to the absorption band from combination vibrational modes of water is used to weld together ex vivo porcine aorta. In these studies we measured the optimal laser power and scan speed, for better tensile strength of the weld and lesser tissue dehydration. Significant amount of water loss from the welded tissue results in cellular death and tissue buckling. Various thermally conductive optical cover windows were used as heat sinks to reduce thermal effects during LTW for the dissipation of the heat. The optimal use of the method prevents tissue buckling and minimizes the water loss. Diamond, sapphire, BK7, fused silica, and IR quartz transparent optical cover windows were tested. The data from this study suggests that IR-quartz as the material with optimal thermal conductivity is ideal for laser welding of the porcine aorta.