Evaporative water loss and the role of cocoon formation in Australian frogs

1998 ◽  
Vol 46 (5) ◽  
pp. 405 ◽  
Author(s):  
Philip C. Withers
Keyword(s):  
Water Content ◽  
Water Loss ◽  
High Water ◽  
Linear Increase ◽  
Evaporative Water Loss ◽  
High Water Content ◽  
Evaporative Water ◽  
Wide Range ◽  
Very High

Measurements of evaporative water loss (EWL; mg min-1) and resistance (R; sec cm-1) for various Australian frogs indicate three general allometric patterns: non-cocooned and non-‘waterproof’ frogs with EWL ∝ Mass0.30 and R independent of body mass at about 1–3 sec cm-1, cocooned frogs with EWL reduced about 50–200-fold and R about 50–200 sec cm-1, and ‘waterproof’ frogs with EWL reduced about 5–100- fold and R about 5–100 sec cm-1. Cocooned frogs have an exponential reduction in EWL and fairly linear increase in R over time, corresponding to the temporal addition of layers to the cocoon. The biophysical properties of cocoon are generally similar for various species, although there is some variation in both resistance per thickness (5–20 × 104 s cm-2) and diffusion coefficient (0.4–2.4 × 10 –5 cm2 s-1). The hygroscopic property of frog cocoon resembles that of mammalian stratum corneum, hair and wool, and mucopolysaccharides; there is a slight increase in water content of cocoon over a wide range of humidities but a very steep increase in water content and substantial hydration and swelling at >96% RH. This extreme hygroscopic behaviour of frog cocoon at very high RH may reflect less polymer cross-linking in frog cocoon and its high digestibility. The prevention of over-hydration of frog cocoon in vivo may be attributed to the restriction of high water content to only very high RH (>96%).

Tough, Stimuli-Responsive, and Biocompatible Hydrogels with Very High Water Content

2018 ◽  
Vol 39 (23) ◽  
pp. 1800474 ◽  
Author(s):  
Tianqi Liu ◽  
Shuai Lu ◽  
Xin Peng ◽  
Chen Jiao ◽  
Jianan Zhang ◽  
...  
Keyword(s):  
Water Content ◽  
High Water ◽  
High Water Content ◽  
Stimuli Responsive ◽  
Very High

scholarly journals Numerical Sensitivity Analysis for Dielectric Characterization of Biological Samples by Open-Ended Probe Technique

Sensors ◽  
2020 ◽  
Vol 20 (13) ◽  
pp. 3756
Author(s):  
Marta Cavagnaro ◽  
Giuseppe Ruvio
Keyword(s):  
Water Content ◽  
Ex Vivo ◽  
High Water ◽  
Biological Tissues ◽  
Fundamental Aspect ◽  
High Water Content ◽  
Insertion Depth ◽  
Dielectric Characterization

Dielectric characterization of biological tissues has become a fundamental aspect of the design of medical treatments based on electromagnetic energy delivery and their pre-treatment planning. Among several measuring techniques proposed in the literature, broadband and minimally-invasive open-ended probe measurements are best-suited for biological tissues. However, several challenges related to measurement accuracy arise when dealing with biological tissues in both ex vivo and in vivo scenarios such as very constrained set-ups in terms of limited sample size and probe positioning. By means of the Finite Integration Technique in the CST Studio Suite® software, the numerical accuracy of the reconstruction of the complex permittivity of a high water-content tissue such as liver and a low water-content tissue such as fat is evaluated for different sample dimensions, different location of the probe, and considering the influence of the background environment. It is found that for high water-content tissues, the insertion depth of the probe into the sample is the most critical parameter on the accuracy of the reconstruction. Whereas when low water-content tissues are measured, the probe could be simply placed in contact with the surface of the sample but a deeper and wider sample is required to mitigate biasing effects from the background environment. The numerical analysis proves to be a valid tool to assess the suitability of a measurement set-up for a target accuracy threshold.

scholarly journals Farmer Group of Cabe Bakul (Lada Katokkon) in Rantepao District, North Toraja Regency

2021 ◽  
Vol 2 (1) ◽  
pp. 27-35
Author(s):  
A. Sry Iryani ◽  
Agustina Deka Minggu Bali
Keyword(s):  
Water Content ◽  
Economic Value ◽  
High Water ◽  
Sweet Taste ◽  
High Water Content ◽  
Chili Powder ◽  
Processed Products ◽  
Very High

Chili is one of the most important foods for traditional Indonesian food. One of the chilies that have a very high Scoville rating from Toraja Utara and Tana Toraja is Cabe Bakul or Lada Katokkon. This chili is different from other peppers ranging from the shape that resembles a pabrika but the size is small, it is sweet taste turned hot and good smelled. . The disadvantage of this chili is the condition of chilies that have a very high water content so it is easy to rot and wrestle so that the price quickly goes down and sometimes thrown away. To avoid the problem, the team proposes to process chili into a product but does not change the taste, color, and smell. This activity helps the chili farmers to process their crops into processed products that have higher economic value. There are two types of products produced are Chili powder (Bon Cabe) and sauce. Chili sauce is made there are four variants of flavors are: original, onion, terasi, and fish. Through this training, the farmer group partners can cultivate the harvest and its products can compete in the Toraja market and outside Toraja. Abstrak Cabe merupakan salah satu makanan terpenting untuk makanan tradisional Indonesia. Salah satu cabai yang memiliki rating Scoville sangat tinggi dari Toraja Utara dan Tana Toraja adalah Cabe Bakul atau Cabe Katokkon. Cabe ini berbeda dengan cabe lainnya mulai dari bentuknya yang menyerupai pabrika namun ukurannya kecil, rasanya manis berubah menjadi panas dan harum. Kekurangan dari cabe ini adalah kondisi buah cabe yang memiliki kandungan air yang sangat tinggi sehingga mudah membusuk dan bergelut sehingga harganya cepat turun dan kadang dibuang begitu saja. Untuk menghindari masalah tersebut, tim mengusulkan untuk mengolah cabe menjadi sebuah produk namun tidak merubah rasa, warna dan baunya. Kegiatan ini membantu petani cabe mengolah hasil panennya menjadi produk olahan yang memiliki nilai ekonomi lebih tinggi. Ada dua jenis produk yang dihasilkan yaitu bubuk cabe (Bon Cabe) dan saos. Kuah sambal yang dibuat ada empat varian rasa yaitu: original, bawang, terasi dan ikan. Melalui pelatihan ini para mitra kelompok tani dapat membudidayakan hasil panen dan produknya dapat bersaing di pasar Toraja dan luar Toraja.

STUDIES IN TREE PHYSIOLOGY: I. GENERAL INTRODUCTION. WATER CONTENTS OF CERTAIN CANADIAN TREES

1939 ◽  
Vol 17c (12) ◽  
pp. 460-482 ◽  
Author(s):  
R. Darnley Gibbs
Keyword(s):  
Water Content ◽  
Populus Tremuloides ◽  
Weather Conditions ◽  
High Water ◽  
High Water Content ◽  
White Pine ◽  
General Introduction ◽  
Very High ◽  
Considerable Loss ◽  
Water Contents

Previous work by the author on the water contents of Canadian trees is reviewed and followed by a brief discussion of questions yet to be answered.In Betula alba v. papyrifera, in at least the young parts of B. alba v. pendula laciniata, in B. populifolia, and in several sizes of Populus tremuloides, there is a marked seasonal rhythm in water content. The maximum is at leaf opening, the minimum at leaf fall. In poplar but not in birch there is a very high water content in December. During winter a considerable loss of water may occur. A winter loss is shown also by the wood of hemlock and larch and by twigs and leaves of white pine and hemlock. Losses from leaves are surprisingly small.The behaviour of B. populifolia has been studied for more than three years, and differences have been correlated with observations on weather conditions. Experimental work on movement of water in this species during winter is inconclusive. This work continues.

In Vivo Cutaneous and Perceived Comfort Response to Fabric: Part VI: The Effect of Moist Fabrics on Stratum Corneum Hydration

1997 ◽  
Vol 67 (12) ◽  
pp. 926-931 ◽  
Author(s):  
Kathryn L. Hatch ◽  
Harriet H. Prato ◽  
S. Haig Zeronian ◽  
Howard I. Maibach
Keyword(s):  
Moisture Content ◽  
Stratum Corneum ◽  
Water Loss ◽  
Initial Moisture Content ◽  
Polyester Fabric ◽  
Evaporative Water Loss ◽  
Evaporative Water ◽  
Potential Health ◽  
Stratum Corneum Hydration

Materials placed over human skin may change the stratum corneum (sc) hydration level, an important phenomenon because increases in normal levels of sc hydration pose potential health problems. This study examines the relationship between fabric moisture content and level of sc hydration so that the role of fabric moisture on sc hydration may be better understood. Three fabric/moisture treatments are placed on the sc—3.5-denier polyester fabric with an initial moisture content of 35% and cotton fabrics with either 44% or 75% initial moisture content—then covered with an occlusive dome. sc evaporative water loss (ewl) is measured before treatment placement and after 30 and 60 minutes of contact. The amount of moisture in the fabric at time of removal is calculated two different ways, and three analyses of variance are done using the evaporative water loss and two fabric final moisture content data sets. The rate of ewl is significantly higher after 30 minutes of treatment contact with sc than after 60 minutes of contact. The amount of moisture in the fabrics is significantly less at time 60 than at time 30, implying that the sc is more hydrated at 30 minutes than at 60 minutes. However, the fabrics contain less moisture when removed at 60 minutes than at 30 minutes. As fabric moisture content decreases, sc hydration decreases. The question we are not able to answer is “Where does the moisture go that is initially in the fabric?’

Preparation and characterization of modified chitosan for in vitro controlled release of vitamin B12

2013 ◽  
Vol 33 (8) ◽  
pp. 757-765 ◽  
Author(s):  
Ahmed Awadallah-F ◽  
Tahia B. Mostafa
Keyword(s):  
Water Content ◽  
Monomer Concentration ◽  
High Water ◽  
High Water Content ◽  
Vitamin B ◽  
Acryloyl Chloride ◽  
Modified Chitosan ◽  
Increase With Increase

Abstract Graft copolymerization of acrylonitrile and acryloyl chloride on to chitosan was prepared by γ-rays. Optimization of the grafting (%) was studied. The grafting (%) was observed to increase with increase in the irradiation dose and monomer concentration. The grafting percentages were about 52% and 36% from polyacrylonitrile and poly(acryloyl chloride), respectively. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were used to characterize the specimens. The modified chitosan was loaded with vitamin B12, demonstrated nearly 5.0±2.3% and 50.1±4.5% release in the media of pH 1.2 and 6.8, respectively, for amidoximated chitosan-grafted polyacrylonitrile and 3.6±1.1% and 36±2.4% in pH 1.2 and 6.8, respectively, for chitosan-grafted poly(acryloyl chloride), as determined by a traditional dissolution model. The modified chitosan specimens that uploaded with vitamin B12 displayed a more decremental release in the acidic medium than the neutral one. However, in order to incorporate in vivo gastrointestinal conditions, such as acidic pH and high water content in the stomach, low water content, and the presence of semi-solid mass in the large intestine, a new model, called flow through diffusion cell, was also used to study the drug release. The results of the two approaches produced different release profiles at the same pH values.

scholarly journals Optimalization of multiresidue method for the determination of pesticide residues in fruits

2021 ◽  
Vol 61 (3) ◽  
pp. 221-238
Keyword(s):  
Water Content ◽  
Pesticide Residues ◽  
High Water ◽  
High Water Content ◽  
Detector Response ◽  
Wide Range ◽  
Comprehensive Determination ◽  
Selective Detectors ◽  
Active Substances

The main aim of this study was to optimize the QuEChERS methodology for the comprehensive determination of pesticide residues using a simple and inexpensive gas chromatography equipped with selective detectors working simultaneously (GC-ECD/NPD). The method was validated in accordance with the SANTE/11945/2015 guidelines. Representative fruit matrices were chosen from the commodities group with high water content (apples), and with high acidity and high water content (strawberry) for a 160 compounds in the range of 0.005−0.02 mg/kg. The accuracy of the method was as required (recovery: 70–120%, precision: below 20%) for 135 active substances in apples samples and 137 in strawberries samples. The main advantages of the methodology include: good detector response linearity (R2 above 0.995), low limits of detection (0.005 mg/kg for more than 20 compounds, 0.01 mg/kg for about 120 compounds), possibility of simultaneous determination of a wide range of compounds (including some “difficult” ones) without use of a single residue methods. The simultaneous use of two selective detectors allows to obtain more data during a single dose of the sample and confirmation of the result for most compounds, which allows to prevent false positives ones.

Behavior of Mexico City clay subjected to undrained repeated loading

1989 ◽  
Vol 26 (1) ◽  
pp. 159-162 ◽  
Author(s):  
J. Abraham Diaz-Rodriguez
Keyword(s):  
Water Content ◽  
Mexico City ◽  
High Water ◽  
Elastic Behavior ◽  
Triaxial Tests ◽  
High Water Content ◽  
Repeated Loading ◽  
Silty Clay ◽  
Undisturbed Soil ◽  
Very High

This note describes a series of cyclic triaxial tests on undisturbed soil samples of Mexico City clay, obtained near the SCT building. The site is a silty clay deposit of a very high water content and soft consistency. The material exhibits elastic behavior in spite of its very high water content. Three empirical relationships describing an equivalent Young's modulus, an equivalent damping ratio, and a cyclic stress level, associated with cyclic strain level, were obtained. Test results define two different patterns of strength loss. Key words: undrained strength, repeated load, clay, modulus, damping, Mexico City.

scholarly journals The role of ambient temperature and body mass on body temperature, standard metabolic rate and evaporative water loss in southern African anurans of different habitat specialisation

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e7885 ◽  
Author(s):  
Mohlamatsane Mokhatla ◽  
John Measey ◽  
Ben Smit
Keyword(s):  
Body Temperature ◽  
Metabolic Rate ◽  
Body Mass ◽  
Water Loss ◽  
Standard Metabolic Rate ◽  
Evaporative Water Loss ◽  
Evaporative Water ◽  
Habitat Specialisation ◽  
Wide Range

Temperature and water availability are two of the most important variables affecting all aspects of an anuran’s key physiological processes such as body temperature (Tb), evaporative water loss (EWL) and standard metabolic rate (SMR). Since anurans display pronounced sexual dimorphism, evidence suggests that these processes are further influenced by other factors such as vapour pressure deficit (VPD), sex and body mass (Mb). However, a limited number of studies have tested the generality of these results across a wide range of ecologically relevant ambient temperatures (Ta), while taking habitat use into account. Thus, the aim of this study was to investigate the role of Ta on Tb, whole-animal EWL and whole-animal SMR in three wild caught African anuran species with different ecological specialisations: the principally aquatic African clawed frog (Xenopus laevis), stream-breeding common river frog (Amietia delalandii), and the largely terrestrial raucous toad (Sclerophrys capensis). Experiments were conducted at a range of test temperatures (5–35 °C, at 5 °C increments). We found that VPD better predicted rates of EWL than Ta in two of the three species considered. Moreover, we found that Tb, whole-animal EWL and whole-animal SMR increased with increasing Ta, while Tb increased with increasing Mb in A. delalandii and S. capensis but not in X. laevis. Whole-animal SMR increased with increasing Mb in S. capensis only. We did not find any significant effect of VPD, Mb or sex on whole-animal EWL within species. Lastly, Mb did not influence Tb, whole-animal SMR and EWL in the principally aquatic X. laevis. These results suggest that Mb may not have the same effect on key physiological variables, and that the influence of Mb may also depend on the species ecological specialisation. Thus, the generality of Mb as an important factor should be taken in the context of both physiology and species habitat specialisation.

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