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In recent years, evidence has emerged about the importance of healthy fluid intake in children for physical and mental performance and health, and in the prevention of obesity. Accurate data on water intake are needed to inform researchers and policymakers and for setting dietary reference values. However, to date, there are few published data on fluid or water intakes in children. This is due partly to the fact that drinking water is not always reported in dietary surveys. The aim of this paper is to review the current status of the literature and highlight the challenges of assessing total fluid intake in children and adolescents. From the dietary assessment literature it is apparent that children present unique challenges to assessing intake due to ongoing cognitive capacity development, limited literacy skills, difficulties in estimating portion sizes and multiple caregivers during any 1 day making it difficult to track intakes. As such, many issues should be considered when assessing total fluid intakes in children or adolescents. Various methods to assess fluid intakes exist, each with its own strengths and weaknesses; the ultimate choice of method depends on the research question and resources available. Based on the literature review, it is apparent that if the research focus is to assess only fluid intake, a fluid-specific method, such as a diary or record, appears to be a feasible approach to provide an accurate estimate of intakes.

A variety of dust control methods are often applied in coal mines, among which the application of wet scrubbers has proven to be an efficient technology for the removal of dust in airstreams, rather than diluting or confining the dust. In this paper, a wet scrubber design was developed. Based on a self-designed experimental test platform, the total dust concentration, respirable dust concentration, air volume, and average pressure drops of wet scrubbers with 12, 16, 20, and 24 blades were measured under different water intake conditions. The results show that the different water intake levels have only minimal effects on the air volume of the wet scrubbers. However, increased water intake had improved the dust removal efficiency of the wet scrubbers with the same number of blades. The wet scrubber with 16 blades was found to have the best dust removal efficiency at a water intake level of 1.35 m3/h. Its total dust and respirable dust removal efficiency reached 96.81% and 95.59%, respectively. The air volume was 200.4 m3/min, and the average pressure drop was determined to be 169.4 Pa. In addition, when the wet scrubber with 16 blades was applied in a coal preparation plant in China’s Shanxi Province, it was observed that the total dust concentration had fallen below 8.1 mg/m3, and the respirable dust concentration had fallen below 5.9 mg/m3. Therefore, the results obtained in this research investigation provide important references for the use of wet scrubbers to improve coal production environmental conditions.

A vast population of the world is vulnerable to fluoride contaminated drinking water intake, and there are various defluoridation techniques available to date as well. But the removal of fluoride is still a challenge, especially in remote rural areas because available techniques require proper supervision and equally, ineffective due to economic issues and electricity crisis. Among all methods of defluoridation, adsorption methods are found better to carry out at the community and household level but sometimes demanded a replacement of commercial activated carbon (CAC) due to economic issues and less availability in remote areas. Hence keeping this in mind, the present study assessed the pine cone activated carbon (PCAC) as adsorbent material in the defluoridation that is easy to prepare like any other agriculture-waste material. The activated carbon was prepared using KOH as an impregnating agent for activation of pine cone by pyrolysis technique at 800 °C and has been analyzed for various parameters in the fluoride removal viz. contact time, dose variation, pH and initial fluoride concentration. The maximum adsorption capacity of fluoride on pine cone activated carbon was found 1.34 mg/g of initial fluoride concentration (2–12 mg/L) at pH (6.8–7.0) with a contact period of 45 min. Also, a comparison has been made between Pine Cone Activated Carbon (PCAC) with Commercial Activated Carbon (CAC) based on obtained results. It has been suggested that Pine cone activated carbon is efficient as well as cheap adsorbent and can be used for the removal of fluoride from drinking water in rural areas.

Small dams managed by local governments in the Republic of Korea are facing operational difficulties owing to problems such as a decrease in the long-term storage capacity because of sedimentation and leakage, acceleration of aging, rapid lowering of water levels with seasonal rainfall and water usage, and the resulting deterioration of the overall integrity. However, the public demand for small dams has increased sharply for various purposes, especially flood and drought control. This paper presents a developed model for evaluating the condition of small dams using an analytic hierarchy process. Seventy-five earth dams in a province located in the eastern part of the Korean Peninsula were chosen. Three major components of dams, i.e., embankments, spillways, and water intake facilities, as well as the overall condition of the dam system, were evaluated. The usefulness of the improved model and its differences from the existing method were verified using the t-test. The improved model was found to be relatively simple and easy to apply in practice, and it enables on-time action for further treatment or reinforcement.

This review is concerned primarily with the nature and origin of the forces bringing about movement of water from soil or other media surrounding roots into the conducting elements of the xylem, and with those internal and external factors which affect the rate of such movement. Absorption of water is not an independent process, but is closely related to other processes included in the domain of plant water relations. The rate of water intake is markedly affected by the rate of transpiration and by the extent and condition of the root systems. It is also affected by such environmental factors as the available moisture content of the soil, soil temperature, soil aeration, and to a lesser extent by the kind and concentration of ions in the soil. Some phases of the work discussed in this review naturally are incomplete and do not permit formulation of definite conclusions concerning certain aspects of the absorption problem. Where the writer has drawn conclusions or made generalizations they seem to be those most justifiable on the basis of the available evidence. It is realized, however, that as knowledge of these processes increases it may be necessary to modify some of the present conclusions. It is impossible to cite all the literature, but most of the papers cited have bibliographies in which the reader can locate other papers dealing with any particular phase of the field.

The present paper is the continuation of a previously published work, (Havre & al., 1960), on the study on conditioned and simple copper deficiency in cattle and sheep in Setesdalen, a valley in the South of Norway. In order to verify molybdenum as a conditioning factor, the fluctuations of the content of molybdenum and copper in the grass during the summer season 1959 have been studied. It was found that the content of both molybdenum and copper increased during the summer and reached its highest values in the first part of August. As stated in the previous paper, the conditioned copper deficiency in Setesdalen was proved to be a disorder occurring on autumnal pasture. From the clinical material collected during the years 1958–60, it may be concluded that the simple copper deficiency in Setesdalen occurs only in the winter season, on stallfeeding. This corresponds fairly well with the fact that the copper content of the herbage has its lowest value about the first of July, the time for grass-mowing in Setesdalen. The seasonal variations of copper and molybdenum were compared with statistics of the precipitation in the investigated areas in the same summer. The content of molybdenum as well as copper in grass was found to be lower in 1959 than in the previous years, probably due to the dry summer in 1959. The molybdenum figures, however, are still above 3 p.p.m. in herbage from areas with conditioned copper deficiency, and the copper figures below 5 p.p.m. in areas with simple copper deficiency. These concentrations were in the first work, in accordance with Cunningham, stated as the “dangerous” limits. In the present work, spectrographs analyses of a series of elements, altogether 18, are carried out on grass samples collected in the summer of 1959. The etiological importance of the various elements is discussed and particular attention is paid to sodium, manganese and sulphur. Sulphur is treated more thoroughly, as the whole herbage material from 1958 has been analysed on total as well as on inorganic sulphur (sulphate), in order to study Dick’s theory on sulphur as a conditioning factor in the syndrome of conditioned copper deficiency. The results of the analyses, however, give no support for sulphur as a conditioning factor in Setesdalen. A hypothetical “copper favouring factor”, possibly vitamin A, is discussed. The clinical observations are discussed in relation to the analytical results. Den foreliggende artikkel er en fortsettelse av et tidligere publisert arbeid om forekomsten av betinget og enkel koppermangel i Setesdalen (Havre & al., 1960). Det naervaerende arbeid har gatt ut pa a verifisere molybdenets virkning som en betingende faktor ved a undersoke svingningene i vegetas jonens innhold av molybden og kopper gjennom sommersesongen 1959. Det ble konstatert at innholdet av bade molybden og kopper steg utover sommeren, og nadde sitt hoydepunkt i forste del av august. Den betingede form for koppermangel i Setesdalen ble i forrige arbeid vist a vaere en beitesykdom pa hostbeite. Det samlede kliniske materiale fra arene 1958–60 har vist at den enkle koppermangel utelukkende forekommer pa inneforing i vinterhalvaret. Dette korresponderer bra med at kopperinnholdet i vegetas jonen viser seg a ha sin laveste verdi ved slattetider omkring 1. juli. Kurvene over molybden- og koppervariasjonene i gras ble ogsa sammenholdt med en nedborsstatistikk for de undersokte omrader samme sommer. Det har vist seg at de fundne verdier i gras for savel molybden som kopper, i denne sesong la lavere enn arene for, hvilket antakelig skyldes den torre sommer i 1959. Verdiene la imidlertid fremdeles over 3 p.p.m. molybden i omrader med betinget koppermangel, og under 5 p.p.m. kopper i omrader med enkel.koppermangel. Disse konsentr as joner ble i forrige arbeid, i overensstemmelse med Cunningham, karakterisert som de „farlige” grenser. I det foreliggende arbeid er ogsa utfort spektrografiske analyser av en serie elementer, tilsammen 18, i gras som ble samlet inn sommeren 1959. Betydningen av de forskjellige elementer i relasjon til forekomst av koppermangel-syndromet er droftet, og oppmerksomheten rettes saerlig mot natrium, mangan og svovel. Svovel er behandlet mer inngaende, idet hele vegetasjonsmaterialet som ble samlet inn sommeren 1958 er analysert pa bade total-svovel og uorganisk svovel (sulfat) ; dette for a forsoke a verifisere Dick’s teori om svovel som en betingende faktor ved den betingete koppermangel. Analyseresultatene gir imidlertid ingen direkte stotte for at svovel virker betingende under de radende forhold i Setesdalen. En hypotetisk „koppervennlig faktor”, muligens vitamin A, er droftet. De kliniske observasjoner er droftet i relation til de analytiske resultater.

Disturbances in internal water equilibrium can be debilitating for mammals. Two studies pinpoint areas of the mouse brain that respond to and anticipate thirst, preserving systematic fluid regulation. See Letters p.680 & p.685 It is vital for mammals to maintain their internal water equilibrium. The neurobiological mechanisms linking thirst response behaviour and fluid balance maintenance raise intriguing questions, given that these two components operate on different timescales. Two papers in this issue of Nature identify areas of the mouse brain that respond to and anticipate thirst. Zachary Knight and colleagues reveal a role for thirst-promoting neurons in the subfornical organ (SFO). During eating and drinking, feedback from the oral cavity to the SFO—one of the three sensory circumventricular organs of the brain—is integrated with information regarding blood composition, providing an indication of how oral consumption is likely to alter fluid balance, leading to behavioural adjustments. Charles Bourque and colleagues identify a projection from central clock neurons that drives anticipatory water intake just prior to sleep, regardless of physiological need. Without this specifically timed increase in water intake, animals suffered from dehydration near the end of a period of sleep.