Computer-compatible system for continuous volumetric measurement of water consumption?

An inexpensive drinkometer system is described that is compatible with most data acquisition systems and can be used for continuously monitoring the drinking pattern of laboratory animals. The change in electrical inductance resulting from the descent of a free-floating ferrite unit through a drinking tube, surrounded by a double coil, is converted to a signal proportional to the volume of fluid consumed.     

农村水资源自动化量测系统

针对我国目前农村水资源量测和管理水平较低，农村用水系统效率低下的问题，介绍农村水资源自动化量测系统的研制和应用。该系统应用先进的电子量测技术、计算技术及多项专利技术，采用最新研制的新型流速旋浆传感器、多功能智能流速仪和流速流向仪同步测量大型农业灌区的渠道流速与流量。该系统在祁东县曹口堰示范区水库灌区的应用表明，渠系水利用率可提高10％，实现了水资源量测与管理的数字化、动态化、智能化与一体化。     

Sea water consumption by two strains of mice

Résumé Deux espèces de souris (IHB et A) vécurent 1 an avec un régime d'eau de mer ad libitum et d'aliments secs. La haute osmolarité urinaire, la capacité élevée de concentrer le sodium et l'absence de diarrhée furent des facteurs qui leur permirent de supporter ce régime expérimental.

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This study was supported by grants No. AM 07257-03 and No. NB 01147-09 from the U.S. Public Health Service.

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NIH Medical Study Research Fellow.     

The effect of ouabain on water consumption in the rat

Résumé L'ouabain diminue la consommation d'eau, stimulée par l'injection d'une solution sallée hypertonique, chez les rats normaux ou néphrectomisés.     

Permeability of arthrodial membrane to water: A first measurement using in vivo techniques

Summary Despite differences in surface morphology and fine structure, the permeabilities of untreated scorpion sternite and pleural cuticle to water are similar (0.69 versus 0.79 g·cm^–2·h^–1·mm Hg^–1). Hexane applied to pleural membrane increased its permeability 9-fold, but neither hexane nor chloroform: methanol had much effect on sternite permeability. When sternite cuticle was treated with 1.0 N KOH followed by chloroform: methanol, permeability increased about three times over control values. In contrast, cockroach pronotum, which is 17 times more permeable than scorpion sternite, exhibited a marked increase in permeability when treated with just hexane. In both the scorpion pleuron and cockroach pronotum, disruption of the lipid barrier caused by rubbing is partially responsible for the higher permeabilities observed following solvent treatment.     

The renal plumbing system: aquaporin water channels

Aquaporins are channels that facilitate movement of water across lipid bilayers. They are expressed in multiple tissues and are essential for regulation of body water homeostasis. The kidney is the main organ responsible for this regulation, and at least seven aquaporins are expressed at distinct sites in the kidney. Aquaporin expression correlates with observed water permeability of each nephron segment: proximal tubule and descending thin limb of Henle have constitutive high water permeability due to expression of AQP1, whereas collecting duct water permeability is tightly regulated by the antidiuretic hormone vasopressin via regulation of AQP2. This review aims at providing insight into renal aquaporins, with special focus on AQP2.Received 9 December 2004; received after revision 8 April 2005; accepted 11 April 2005     

Effect of water oxygenation on oxygen consumption and gill ventilation of the crab, Carcinus maenas (L.)]

At 15 degrees C, the oxygen uptake rate of Carcinus maenas was practically independent of the ambient oxygen pressure betueen 50 and 500 Torr. Within this range, hyperventilatory and hypoventilatory responses were observed in hypoxic and hyperoxic conditions respectively whereas the oxygen extraction coefficient remained more or less constant.     

Effect of the excision of leaf tissues on the measurement of their water potential with thermocouple psychrometer

Résumé Le potentiel d'eau, mesuré dans un psychromètre à thermocouple, se révèle être plus haut dans les feuilles coupées que dans les feuilles intactes.     

A new continuous optical assay for isocitrate lyase

Summary A new continuous optical assay method for isocitrate lyase is reported. This is a coupled assay which requires lactate dehydrogenase as an ancillary enzyme. The method yields linear data up to 0.12 units/ml. The assay is also suitable for crude extracts.Acknowledgment. This research was supported by grants of the Italian Ministero della Pubblica Istruzione.     

An apparatus for the measurement of small tensions

Zusammenfassung Ein Apparat zur Messung von kleinen Spannungen in biologischem Material wird beschrieben. Das System wurde konstruiert, um Störungen durch Milieufaktoren sowie durch Temperatur- und Feuchtigkeitsvariationen und Vibrationen zu eliminieren.     

Effects of volumetric allocation on heave response of semisubmersible in deep sea

The configuration of semisubmersibles consisting of pontoons and columns and their corresponding heave motion response in incident progressive waves are examined.The purpose of the present study is to provide a theoretical approach to estimating the effects of volumetric allocation on natural period and response amplitude operator (RAO) in heave motion.We conclude that the amplitude of heave motion response can be considerably suppressed by appropriately adjusting volumetric allocation so that the natural h...     

Insolubility of the quantum measurement problem for unsharp observables

The quantum mechanical measurement problem is the difficulty of dealing with the indefiniteness of the pointer observable at the conclusion of a measurement process governed by unitary quantum dynamics. There has been hope to solve this problem by eliminating idealizations from the characterization of measurement. We state and prove two ‘insolubility theorems’ that disappoint this hope. In both the initial state of the apparatus is taken to be mixed rather than pure, and the correlation of the object observable and the pointer observable is allowed to be imperfect. In the insolubility theorem for sharp observables, which is only a modest extension of previous results, the object observable is taken to be an arbitrary projection valued measure. In the insolubility theorem for unsharp observables, which is essentially new, the object observable is taken to be a positive operator valued measure. Both theorems show that the measurement problem is not the consequence of neglecting the ever-present imperfections of actual measurements.