XXI. Description of a hydropneumatic baroscope

1839 ◽  
Vol 129 ◽  
pp. 425-431

The principle on which the instrument I am about to describe is constructed, is, that the volume of a given quantity of air under a constant temperature, is inversely as the pressure to which it is subjected ; and the means I employ to estimate the change of volume which that quantity of air undergoes, by being subjected to differences of pressure caused by a change of elevation, are the determination of the difference of weight which a floating body is capable of sustaining in both situations. Thus, if a vessel containing a quantity of air and water be floated in water, and there be a com­munication between the water in the floating body and that in which it floats, it will follow, that when such an apparatus is subjected to diminished pressure, the air within the float will dilate, and cause a volume of water equal in amount to the dilatation of the air to be driven from the float; and the difference of weight which the floating body will sustain, will be the exact weight of the water expelled : if such an appa­ratus is subjected to an increased pressure, the air within it will contract, and consequently a quantity of water, from that in which it floats, will enter the float, and the diminished weight it is capable of sustaining will be the weight of the water which has entered the float, in consequence of the diminution of the volume of the air. It is by such means, with the instrument immediately to be described, and by the help of a very simple calculation, that I propose to determine the difference of level between any two places. Plate X. fig. 1. represents the floating part, made of thin sheet brass, the body of which ( a ), in form the frustum of a cone, is nine inches long, two inches in dia­meter at one end, and one inch at the other, and capable of containing about fourteen cubic inches. In the centre of the widest end, a small stud of brass ( b ) is hard sol­dered, into which a brass wire ( c ) is screwed, an inch and three-eighths long, and about one twenty-fifth or one thirtieth of an inch in diameter : the other end of the wire is screwed into a brass stud in the middle of the convex side of a shallow cup ( d ), made also of brass, and as light as possible, so that it will retain its shape, and be capable of sustaining a weight of about eight hundred or one thousand grains.

Author(s):  
D. T. Gauld ◽  
J. E. G. Raymont

The respiratory rates of three species of planktonic copepods, Acartia clausi, Centropages hamatus and Temora longicornis, were measured at four different temperatures.The relationship between respiratory rate and temperature was found to be similar to that previously found for Calanus, although the slope of the curves differed in the different species.The observations on Centropages at 13 and 170 C. can be divided into two groups and it is suggested that the differences are due to the use of copepods from two different generations.The relationship between the respiratory rates and lengths of Acartia and Centropages agreed very well with that previously found for other species. That for Temora was rather different: the difference is probably due to the distinct difference in the shape of the body of Temora from those of the other species.The application of these measurements to estimates of the food requirements of the copepods is discussed.


2003 ◽  
Vol 28 (3) ◽  
pp. 410-423 ◽  
Author(s):  
Gregoire P. Millet ◽  
Robin Candau ◽  
Philippe Fattori ◽  
Frank Bignet ◽  
Alain Varray

The purposes of this study were (1) to determine the time sustained above 90% of [Formula: see text] in different intermittent running sessions having the same overall time run at the velocity ([Formula: see text]) associated with [Formula: see text] and (2) to test whether the use of a fixed-fraction (50%) of the time to exhaustion at [Formula: see text] (Tlim) leads to longer time spent at a high percentage of [Formula: see text]. Subjects were 8 triathletes who, after determination of their track [Formula: see text] and Tlim, performed three intermittent running sessions alternating the velocity between 100% and 50% of [Formula: see text], termed 30s ∼ 30s, 60s ∼ 30s, and 1/2Tlim ∼ 1/2Tlim, where the overall time at [Formula: see text] was similar (= 3 × Tlim). [Formula: see text] achieved in the incremental test was 71.1 ± 3.9 mlùmin−1•kg−1 and Tlim was 236 ± 49 s. [Formula: see text] and peak heart rate were lower in 30s ∼ 30s than in the other intermittent runs. The time spent above 90% of [Formula: see text] was significantly (p < 0.001) longer either in 60s ∼ 30s (531 ± 187 s) or in 1/2Tlim ∼ 1/2Tlim (487 ± 176 s) than in 30s ∼ 30s (149 ± 33 s). Tlim was negatively correlated with the time (in % of Tlim) spent above 90% of [Formula: see text] in 30s ∼ 30s (r = -0.75, p < 0.05). Tlim was also correlated with the difference of time spent over 90% of [Formula: see text] between 60s ∼ 30s and 30s ∼ 30s (r = 0.77, p < 0.05), or between 1/2Tlim ∼ 1/2Tlim and 30s ∼ 30s (r = 0.97, p < 0.001). The results confirm that [Formula: see text] and Tlim are useful for setting interval-training sessions. However, the use of an individualized fixed-fraction of Tlim did not lead to longer time spent at a high percentage of [Formula: see text] compared to when using a fixed work-interval duration. Key words: interval-training, maximal oxygen consumption, performance, time to exhaustion


1917 ◽  
Vol 25 (2) ◽  
pp. 341-347 ◽  
Author(s):  
Tokuzo Ohira ◽  
Hideyo Noguchi

Trichomonades from the mouth were studied by Steinberg who proposed to group them into three distinct types; namely, Trichomonas elongata, Trichomonas caudata, and Trichomonas flagellata. Doflein (3) regards them as probably identical with Trichomonas hominis. Opinions differ as to whether or not Trichomonas vaginalis Donné and Trichomonas hominis Grassi are the same species. Lynch, for instance, believes that they are the same species, while von Prowazek (4), Bensen (5), and others (6, 7) insist that they are different types. Bensen's view seems to be well supported by the difference alleged to be found between the mode of encystment in the two trichomonades, were it not for the fact that our knowledge about the so called cyst of trichomonades is still obscure. According to Alexeieff (8) many of the so called cysts were evidently blastomyces contained in the cell body of the trichomonas. An autogamy alleged to take place in cysts as described by Bohne and von Prowazek (9) has not been confirmed by Dobell (10). And Wenyon (11) contends that it has never been found possible to produce any development of these cysts outside the body on the warm stage as can be done with the cysts of Entamœba coli. Therefore, it is still premature to take the process of encystment into consideration as far as the classification of trichomonas is concerned. On the other hand, Rodenwaldt (12) seems to think that there are many species of trichomonas in the human intestines, and Wenyon has described a new trichomonas from the human intestines (Macrostoma mesnili Wenyon). Further cultural studies in the morphology and biology of these organisms must be carried out in order to solve these problems. In the light of modern investigations there are five subgenera to be included under the genus Trichomonas Donné. They are as follows: (1) Protrichomonas Alexeieff, with three anterior flagella, without an undulating membrane. (2) Trichomastix Biitschli) with three anterior flagella and a trailing flagellum (Schleppgeissel) without an undulating membrane. (3) Trichomonas Donné, with three anterior flagella and an undulating membrane. (4) Macrostoma Alexeieff, Amend, Wenyon (11), with three anterior flagella and an undulating membrane wedged in a deep groove (peristome). (5) Tetratrichomonas Parisi (13), with four anterior flagella and an undulating membrane. As far as our culture trichomonas from the human mouth is concerned, it has been shown that it is not strictly a trichomonas and that it should be classed under the subgenus Tetratrichomonas.


2012 ◽  
Vol 22 (01n02) ◽  
pp. 201-206 ◽  
Author(s):  
S. HIRAISHI ◽  
K. ISHII ◽  
S. MATSUYAMA ◽  
H. SUGAI ◽  
Y. MIURA ◽  
...  

Growth environment of plants was investigated by analyzing the elemental concentration in leaves of the plants. Camellia was selected as the sample and the leaves of the camellias were collected from Miyagi and Chiba prefectures. The species of elements and their concentrations in the leaves were measured by the in-air PIXE system at Tohoku University. More than 10 elements were detected from the leaves. The concentrations of Mn , Fe , and Rb in the leaves were strongly affected by the place where the tree grew. On the other hand, the concentration of P, S, K, and Ca were less affected by the place of the tree. The determination of the place of the tree was also performed by evaluating the similarity of the elemental concentration in the leaves quantitatively. The difference due to the place was clearly identified and the sampling place was successfully determined by using the elemental concentrations in the leaves.


2000 ◽  
Vol 417 ◽  
pp. 157-181 ◽  
Author(s):  
A. A. KOROBKIN ◽  
D. H. PEREGRINE

The initial stage of the water flow caused by an impact on a floating body is considered. The vertical velocity of the body is prescribed and kept constant after a short acceleration stage. The present study demonstrates that impact on a floating and non-flared body gives acoustic effects that are localized in time behind the front of the compression wave generated at the moment of impact and are of major significance for explaining the energy distribution throughout the water, but their contribution to the flow pattern near the body decays with time. We analyse the dependence on the body acceleration of both the water flow and the energy distribution – temporal and spatial. Calculations are performed for a half-submerged sphere within the framework of the acoustic approximation. It is shown that the pressure impulse and the total impulse of the flow are independent of the history of the body motion and are readily found from pressure-impulse theory. On the other hand, the work done to oppose the pressure force, the internal energy of the water and its kinetic energy are essentially dependent on details of the body motion during the acceleration stage. The main parameter is the ratio of the time scale for the acoustic effects and the duration of the acceleration stage. When this parameter is small the work done to accelerate the body is minimal and is spent mostly on the kinetic energy of the flow. When the sphere is impulsively started to a constant velocity (the parameter is infinitely large), the work takes its maximum value: Longhorn (1952) discovered that half of this work goes to the kinetic energy of the flow near the body and the other half is taken away with the compression wave. However, the work required to accelerate the body decreases rapidly as the duration of the acceleration stage increases. The optimal acceleration of the sphere, which minimizes the acoustic energy, is determined for a given duration of the acceleration stage. Roughly speaking, the optimal acceleration is a combination of both sudden changes of the sphere velocity and uniform acceleration.If only the initial velocity of the body is prescribed and it then moves freely under the influence of the pressure, the fraction of the energy lost in acoustic waves depends only on the ratio of the body's mass to the mass of water displaced by the hemisphere.


2018 ◽  
Vol 4 (1) ◽  
pp. 167
Author(s):  
Kuntarno Noor Aflah

Poverty has many definitions, parameters, and standards. From the viewpoint of Islam, many theologians define and measure poverty by various terms and sizes. The difference among theologians’ opinion is caused by poverty terms contained in the Qur’an and Hadits. “Fakir” and “poor” have many meanings. It allows a wide interpretation of the verse and word from theologians. It is also seen from the regulation point in Indonesia, there are many definitions, standards and parameters of poverty. The difference of point of view on determination of poverty criteria and regulations according to Islam in Indonesia shows that the ways of ijtihad by theologians and the government elements is very open. The absence of standard stipulation held, encouraging the writer to conduct a comparative research in this paper; through literacy research. Syafi’i sect does not specify a quantitative standard for poverty. Poverty is only categorized on requirement. As long as people are not able to cover 50% of their basic needs, they are called as fakir. If people are only able to cover close to 70% of their basic needs then they are categorized as poor. Meanwhile, according to Hanafi sect, the qualitative standards turned to the Syafi’i sect. Poor conditions are more severe than the fakir. Besides,the quantitative standard of poverty is one nisab of zakat or the equivalent of 85 grams of gold. On the other hand, BPS and BKKBN formulate the concept and standard of poverty by economic concepts. Poverty is conceptualized as the inability of someone to meet basic consumption needs of the formulation adapted to local conditions respectively.


2021 ◽  
Vol 17 (2) ◽  
pp. 62-67
Author(s):  
Oleg Chuykin ◽  
Maria Shtanko ◽  
Kristina Kuchuk

To maintain homeostasis of the internal environment of the body, mechanisms are needed that control the exchange of various components between blood and the internal environment of tissues and organs. One of these physiological structures is the blood-salivary barrier, which regulates the selective metabolism between blood and oral fluid. Changes in the composition of biological fluids (blood and saliva) can be used as markers for diagnosing pathological conditions of the body and the dynamics of therapeutic measures. Of great importance is the study of the blood-salivary barrier for the search for drugs that are selectively transferred from the blood to the saliva. Some drugs are excreted in saliva at a concentration higher than they are in the blood. However, more often the concentration of drugs in saliva is much lower than in blood serum. Purpose: to form a list of the main trends and scientific and practical directions on the func-tioning of the hematosalvarial barrier. Materials and methods: to analyze the topic of the clinical significance of the hematosalvarial barrier, periodicals and scientific journals of domestic and foreign literature were studied, which determined the difference in the levels of trace elements, hormones, immune complexes between the oral fluid and serum. Conclusion: Analysis of literature data shows that the function of the blood-salivary barrier acts as a nonspecific adaptive mechanism, while saliva reflects the state of the protective functions of the barrier at the organismal level. Analysis of the selectivity and permeability of the blood-salivary barrier, as well as determination of changes in the composition and proper-ties of blood and oral fluid, can optimize and facilitate the diagnosis and control of treatment of various diseases of the oral cavity and the body as a whole.


1964 ◽  
Vol 6 (1) ◽  
pp. 119-123 ◽  
Author(s):  
R. L. Van Spaendonck ◽  
F. X. Vanschoubroek

SUMMARYIn determining the milk yield of the sow by weighing the litter before and after suckling, loss of weight due to metabolic processes must be considered.An experiment is described to investigate the loss of weight of piglets caused by metabolic processes between two consecutive weighings, and to investigate the relationship between this loss on the one hand and the body weight and the age of the piglets on the other. Weight changes of 15 litters of average 9·8 piglets were studied during 66 weighing periods of 16 minutes, by putting the pigs in a cage, fixed on a differential balance. Each weighing period consisted of 8 periods of 2 minutes, so that in all, loss of weight was studied during 528 2-minute periods.


2013 ◽  
Vol 135 (8) ◽  
Author(s):  
Vít Průša ◽  
K. R. Rajagopal ◽  
U. Saravanan

Practically all experimental measurements related to the response of nonlinear bodies that are made within a purely mechanical context are concerned with inhomogeneous deformations, though, in many experiments, much effort is taken to engender homogeneous deformation fields. However, in experiments that are carried out in vivo, one cannot control the nature of the deformation. The quantity of interest is the deformation gradient and/or its invariants. The deformation gradient is estimated by tracking positions of a finite number of markers placed in the body. Any experimental data-reduction procedure based on tracking a finite number of markers will, for a general inhomogeneous deformation, introduce an error in the determination of the deformation gradient, even in the idealized case, when the positions of the markers are measured with no error. In our study, we are interested in a quantitative description of the difference between the true gradient and its estimate obtained by tracking the markers, that is, in the quantitative description of the induced error due to the data reduction. We derive a rigorous upper bound on the error, and we discuss what factors influence the error bound and the actual error itself. Finally, we illustrate the results by studying a practically interesting model problem. We show that different choices of the tracked markers can lead to substantially different estimates of the deformation gradient and its invariants. It is alarming that even qualitative features of the material under consideration, such as the incompressibility of the body, can be evaluated differently with different choices of the tracked markers. We also demonstrate that the derived error estimate can be used as a tool for choosing the appropriate marker set that leads to the deformation gradient estimate with the least guaranteed error.


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