bluuebunny/crossref_metadata_2025_split huggingface dataset:
THE EFFECTS OF POLARIZATION UPON THE STEEL WIRE-NITRIC ACID MODEL OF NERVE ACTIVITY
Authors: Bishop George H. 
Published: May 2004

The active process in a short length of steel wire passivated by 65 per cent nitric acid has been observed under the influence of a polarizing current, and the form of the potential recorded by the cathode ray oscillograph. In the passive wire, 80 per cent of the total potential drop takes place at the anode, 20 per cent at the cathode. The change from active to passive states, as measured by the potential change, is very abrupt compared to the duration of activity and the potential curve at a point on the wire is probably almost rectangular.
The duration of the refractory state is decreased at the anode and increased at the cathode, as in nerve. This fact is against the idea that reactivity after passivation results from a partial reduction of an oxide layer.
Soft iron wire passivated by anodal polarization repassivates after activation in acid of a dilution that fails to passivate it initially. It soon becomes rhythmic with a very short refractory phase, and then reacts continuously. Such a wire exhibits a very sharp alternation between a dark brown oxide coat during activity, and a bright clean surface during passivation.
A passive steel wire in nitric acid shows many of the characteristics of an inert electrode such as platinum, and it may be inferred that, superposed upon the primary passivation potential, there exists an electrode or oxidation-reduction potential equilibrium between the effects of the various constituents of the solution.
It is suggested that the phenomena of nerve-like reactivity in this system may involve an alternation between two protective coatings of the steel wire. During activity, the surface becomes mechanically coated with a brown oxide. If this coating does not adhere, due to gas convection or to rapid solution of the oxide, passivation does not result. Under sufficiently intense oxidizing conditions, a second oxide coat may form in the interstices of the first, and cover the surface as the first coating dissolves off. This furnishes the electrochemical protection of passivation, which is followed by the gradual attainment of electrode equilibrium with the solution.
ON THE RATE OF REACTION BETWEEN ENZYME AND SUBSTRATE
Authors: Berkson Joseph , Flexner Louis B. 
Published: May 2004

1. An equation of the form:
See PDF for Equation
in which vt is the time of flow of the mixture, vw the time of flow for water, vf the time of flow of the mixture when proteolysis is complete, vo the time of flow at the beginning of the experiment, t the time of observation, and r a constant, has been found to describe accurately the course of change of viscosity in a mixture of gelatin and pancreatin.
2. An equation of the same general form has been found to apply similarly to the reaction between other enzymes and other substrates.
3. The equation may be derived theoretically from assuming a bimolecular reaction between enzyme and substrate obeying the mass action law.
INTRACELLULAR OXIDATION-REDUCTION STUDIES
Authors: Cohen Barnett , Chambers Robert , Reznikoff Paul 
Published: May 2004

Twenty-five oxidation-reduction indicators were injected in oxidized or reduced form into Amoeba dubia and Amœba proteus under controlled conditions of oxygen access. (1) Under anaerobiosis the ameba was able to reduce completely all the reversible oxidation-reduction indicators down to and including indigo disulfonate. (2) Under anaerobiosis the ameba was unable to reoxidize six of the most easily oxidizable indicators. (3) Under aerobiosis the ameba was able to reduce completely all the indicators down to and including 1-naphthol-2-sulfonate indo-2, 6-dichlorophenol. Toluylene blue, methylene blue and indigo tetrasulfonate were sometimes completely and sometimes only partly reduced, depending on the quantity of indicator injected and the duration of observation. (4) The time of reduction varied approximately with the size of the injection. Reduction was more rapid under anaerobiosis than under aerobiosis, more rapid in active than in sluggish cells and was retarded by toxic compounds. (5) Sulfonated compounds were somewhat toxic, as a rule.
In interpreting reduction phenomena of micro injection, it is necessary to take into consideration the intensity, capacity and rate factors. It then becomes apparent that the ameba has a high reducing potential lying on the rH scale below the zone of indigo disulfonate. The reducing capacity of the ameba seems to be relatively great in the region of the simple indophenols and of a progressively diminishing magnitude as the zone of the indigos is approached. Material of high reduction potential appears to be generated within the ameba at a measurable rate. These phenomena, observed in the interior of the cell with the aid of indicators, parallel very closely those found in reduction electrode studies on bacterial cultures.
ELECTRIC IMPEDANCE OF SUSPENSIONS OF ARBACIA EGGS
Authors: Cole Kenneth S. 
Published: May 2004

Apparatus has been designed and constructed for the measurement of the electric impedance of suspensions of Arbacia eggs in sea water to alternating currents of frequencies from one thousand to fifteen million cycles per second. This apparatus is simple, rugged, compact, accurate, and rapid.
The data lead to the conclusions that the specific resistance of the interior of the egg is about 90 ohm cm. or 3.6 times that of sea water, and that the impedance of the surface of the egg is probably similar to that of a "polarization capacity". The characteristics of this surface impedance can best be determined by measurements of the capacity and resistance of suspensions of eggs.
No specific change has been found in the interior resistance or the surface impedance which can be related either to membrane formation or to cell division.
HEME AND TISSUE IRON
Authors: Anson M. L. , Mirsky A. E. 
Published: May 2004

1. A method is described for estimating the heme in yeast and bees' muscles as pyridine hemochromogen.
2. The difficulties of the method are discussed.
3. The heme as given by the pyridine method is responsible for about 40 per cent of the total iron.
SPECTROPHOTOMETRIC STUDIES OF PENETRATION
Authors: Irwin Marian 
Published: May 2004

The rate of diffusion through the non-aqueous layer of the protoplasm depends largely on the partition coefficients mentioned above. Since these cannot be determined we have employed an artificial system in which chloroform is used in place of the non-aqueous layer of the protoplasm. The partition coefficients may be roughly determined by shaking up the aqueous solutions with chloroform and analyzing with the spectrophotometer (which is necessary with methylene blue because we are dealing with mixtures). This will show what dyes may be expected to pass through the protoplasm into the vacuole in case it behaves like the artificial system.
From these results we may conclude that the artificial system and the living cell act almost alike toward methylene blue and azure B, which supports the notion of non-aqueous layers in the protoplasm.
There is a close resemblance between Valonia and the artificial system in their behavior toward these dyes at pH 9.5.
In the case of Nitella, on the other hand, with methylene blue solution at pH 9.2 the sap in the artificial system takes up relatively more azure B (absorption maximum at 650 mµ) than the vacuole of the living cell (655 mµ). But both take up azure B much more rapidly than methylene blue.
A comparison cannot be made between the behavior of the artificial system and that of the living cell at pH 5.5 since in the latter case there arises a question of injury to cells before enough dye is collected in the sap for analysis.
THE COMBINATION OF GELATIN WITH HYDROCHLORIC ACID
Authors: Hitchcock David I. 
Published: May 2004

1. Cooper's gelatin purified according to Northrop and Kunitz exhibited a minimum of osmotic pressure and a maximum of opacity at pH 5.05 ±0.05. The pH of solutions of this gelatin in water was also close to this value. It is inferred that such gelatin is isoelectric at this pH and not at pH 4.70.
2. Hydrogen electrode measurements with KCl-agar junctions were made with concentrated solutions of this gelatin in HCl up to 0.1 M. The combination curve calculated from these data is quite exactly horizontal between pH 2 and 1, indicating that 1 gm. of this gelatin can combine with a maximum of 9.35 x 10–4 equivalents of H+.
3. Conductivity titrations of this gelatin with HCl gave an endpoint at 9.41 (±0.05) x 10–4 equivalents of HCl per gram gelatin.
4. E.M.F. measurements of the cell without liquid junction, Ag, AgCl, HCl + gelatin, H2, lead to the conclusion that this gelatin in 0.1 M HCl combines with a maximum of 9.4 x 10–4 equivalents of H+ and 1.7 x 10–4 equivalents of Cl- per gram gelatin.
PROTEIN COAGULATION AND ITS REVERSAL
Authors: Mirsky A. E. , Anson M. L. 
Published: May 2004

1. The preparation from completely coagulated hemoglobin of crystalline soluble hemoglobin is described.
2. This soluble hemoglobin by all the tests tried has been indistinguishable from normal native hemoglobin which has never been coagulated.
3. The coagulation of hemoglobin is probably reversible.
4. Since hemoglobin is a typical coagulable protein, protein coagulation in general is probably reversible.
OSMOSIS OF LIQUIDS. III
Authors: Schreinemakers F. A. H. 
Published: May 2004

If only one substance S passes through a membrane, the nature of this membrane is not of importance with respect to the direction of the diffusion; this is namely determined only by the O.S.A. of the two liquids.
If, however, more substances pass through a membrane, the nature of this membrane is of great importance.
If n substances diffuse through a membrane, we can distinguish 2n cases, when we take into consideration only the direction in which each of these substances passes through the membrane; if we call each of these cases a D.T. (diffusion-type), 2n D.T.'s may be conceived. Now we can deduce: one of these D.T.'s is not possible, the other 2n x 1 D.T.'s are thermodynamically admissible. The composition of the two liquids determines which of the D.T.'s is not possible; the nature of the membrane determines which of the 2n x 1 other D.T.'s will occur.
THE SORPTION OF BACTERIOPHAGE BY LIVING AND DEAD SUSCEPTIBLE BACTERIA
Authors: Krueger Albert P. 
Published: May 2004

The above data relating to the antistaphylococcus phage and single strain of S. aureus with which previous papers have been concerned (9, 10, 11, 12), bring out the following points.
(a) For live, resting, susceptible B suspended in broth as well as for B in a P-B mixture during the logarithmic phases of B growth and P formation, P is distributed in a manner typical of numerous materials soluble in both phases of a two phase system, i.e., distribution proceeds in accordance with the equation Cb/Ca = K where Cb = extracellular P/ml. of broth and Ca = intracellular P/ml. of B. The combination is quantitatively reversible.
(b) With heat-killed, susceptible B, P distribution is of the adsorptive type, expressible in the form of the adsorption isotherm equation a = kC1/n. The average value of 1/n is 0.80 in agreement with the results of von Angerer (2). Under ordinary conditions dead B take up much more P than do live B, the reaction proceeding to &gt; 99 per cent completion. The combination of P with dead B is not demonstrably reversible and with high initial P/B ratios saturation of B with P is effected. Bacteria killed at 65°C., 80°C. and 100°C. show no differences in adsorptive ability.
(c) The rates at which live, resting, susceptible B and heat-killed, susceptible B remove P from solution do not differ significantly. Velocity constants of the process calculated from
See PDF for Equation
agree satisfactorily. It is shown that the time interval consumed is concerned with an actual reaction between P and B and not with diffusion of P through the broth to B.
(d) P determinations have been found to serve as satisfactory indicators for B growth in P-B mixtures where [B] is to be maintained at a constant level. Very small increments in [B] give rise to measurable increases in P by virtue of the fact that dP/dt is proportional to a power of the rate dB/dt (9).
(e) Similarly [P] estimations will detect death of B cells in P-live B suspensions. Dead B take up large amounts of P irreversibly; such P cannot function in the titration and the result is a sharp drop in [P] of controls.
SALT EFFECTS ON SWARMERS OF DUNALIELLA VIRIDIS TEOD
Authors: Baas-Becking L. G. M. 
Published: May 2004

1. Dunaliella viridis Teodoresco thrives equally well in solutions of NaCl 1 to 4 mol and pH 6 to 9.
2. The organism is sensitive to calcium and magnesium, especially in acid medium.
3. Calcium and magnesium are antagonistic. In a molar solution of NaCl the antagonistic relation Mg:Ca is 4 to 5. In a 4 molar solution of NaCl the proportion becomes many times as great (20:1).
4. Although the strains used in this investigation did not occur in sea water concentrates, the increase in the antagonistic ratio Mg:Ca in which they can live closely paralleled the changes in this ratio which take place when sea water evaporates.
5. The other organisms which occurred in the cultures each show a specific relation to Ca and Mg.
6. The size of the cells of Dunaliella does not decrease with increasing NaCl content.
A CHEMICAL EXPLANATION OF THE VARIABILITY OF THE GROWTH RATE
Authors: Rahn Otto 
Published: May 2004

The general belief that uniform cells under uniform conditions will all multiply at the same moment implies that the smallest units of the chromosomes, i.e., either the genes or the molecules of which the genes are composed, all double at exactly the same moment in all cells.
Since the doubling of chromosomes is a synthetic chemical process, it seems more probable that it would follow chemical laws. With the assumption that the corresponding molecules in a number of uniform cells obey the mass law in their process of doubling, a definite order in the multiplication of identical cells is established which can be formulated mathematically for the simplest case. This is the same assumption which the author has used to account for the differences in the order of death between bacteria and higher organisms.
This theory demands a great variability of the growth rate of uniform cells, so great that it must be experimentally measurable even for cells with a million molecules to the chromosome.
The theory demands further that the frequency curve of cell divisions plotted for successive time intervals, be skewed to the left, and that the relative range of variation become smaller as the number of genes or gene-type molecules increases.
Experiments on the growth rate of Bacterium aerogenes and Saccharomyces ellipsoideus showed regularly a frequency curve skewed to the left. The yeast had a relatively narrower range of variability than the bacterium.
Even with multicellular organisms, theoretical calculations show a range of variation of the growth rate from the egg cell which should still be measurable though it decreases relatively with the number of cells produced. An experiment on the size of bacteria colonies at different ages of development agreed with the theory.
SIMILARITY OF THE KINETICS OF INVERTASE ACTION IN VIVO AND IN VITRO. II
Authors: Wilkes B. G. , Palmer Elizabeth T. 
Published: May 2004

1. The pH-activity relationship of invertase has been studied in vivo and in vitro under identical external environmental conditions.
2. The effect of changing (H+) upon the sucroclastic activity of living cells of S. cerevisiae and of invertase solutions obtained therefrom has been found, within experimental error, to be identical.
3. The region of living yeast cells in which invertase exerts its physiological activity changes its pH freely and to the same extent as that of the suspending medium. It is suggested that this may indicate that this intracellular enzyme may perform its work somewhere in the outer region of the cell.
4. In using live cells containing maltase, no evidence of increased sucroclastic activity around pH 6.9, due to the action of Weidenhagen's α-glucosidase (maltase), was found.
THE ACTION OF X-RAYS ON EUPLOTES TAYLORI AND ASSOCIATED BACTERIA
Authors: Brown Morden G. , Luck J. Murray , Sheets Grace , Taylor C. V. 
Published: May 2004

1. The minimum lethal dose of x-rays for Euplotes taylori was determined. Under the conditions of this investigation a 220 second exposure (2110 Roentgen units per second) was required to kill the protozoon. Much less exposure was sufficient to kill the associated bacteria. This difference in resistance permits the sterilization of protozoa with comparative ease.
2. Irradiation of Euplotes for 100 to 220 seconds caused a complete but temporary cessation of ciliary activity in many of the organisms, the percentage so affected increasing with the length of irradiation.
3. Pure cultures of Pseudomonas fluorescens and Bacillus coli, K13, separately irradiated, were found to be killed much more readily than protozoa,—the former in 15 seconds exposure (2530 Roentgen units per second) and the latter in 45 seconds.
4. The death of these organisms by irradiation was not due to the action of toxic products in the medium since separately irradiated media were not found to be toxic.
5. Irradiated bacteria were found unsatisfactory for the nutrition of Euplotes, previously sterilized either by irradiation or washing.
SPECIFIC NERVE IMPULSES FROM GUSTATORY AND TACTILE RECEPTORS IN CATFISH
Authors: Hoagland Hudson 
Published: May 2004

1. Receptors in the lips and barbels of the catfish Ameiurus nebulosus Les. are very sensitive to mechanical stimuli, giving large rapid (A-type) impulses in fibers of the facial nerve in response to touching the receptive surfaces and to movements of the water in which the preparation is immersed.
2. The great sensitivity of the barbels and lips to currents of water and the bilateral symmetry of the distribution of sensitivity of the facial nerve may serve as a basis for observed rheotropic orientation in the catfish.
3. Acetic acid, NaCl, and meat juice, dissolved in the water bathing the barbels and lips, set up impulses of very small and barely detectable potential in the fibers of the facial nerve.
4. It is suggested that the specificity of impulses for the two sense modalities may be correlated with the large size of the cells of origin of the axons in the Gasserian ganglion supplying tactile receptors and the small size of the cells of origin in the geniculate ganglion sending axons to taste-buds.
THE CONVERSION OF FAT TO CARBOHYDRATE IN THE GERMINATING CASTOR BEAN
Authors: Murlin John R. ,   With the Assistance of William R. Murlin and Jean D. Watkeys
Published: May 2004

1. Respiration studies on single castor beans, made by means of the Brodie-Warburg method, at various times after the start of germination, as well as studies on groups of germinating beans over periods of 3 to 8 days, made by a simple procedure involving analysis of the respired air by the Haldane method, consistently give respiratory quotients from 0.30 to 0.58, indicating the conversion of the oil to carbohydrate.
2. The R.Q. varies with the stage of germination, the lowest point occurring when the new growth (hypocotyl) measures from 20 to 35 mm. in length.
3. The R.Q. of the young plant (cotyledons and hypocotyl), separated from the endosperm and studied in the same apparatus, varies from 0.78 to 1.00. It is invariably high enough to indicate considerable combustion of sugar. The R.Q. of the endosperm alone is low, but usually somewhat higher than that of the entire germinating structure.
4. On the same unit of moist weight the young plant (cotyledons and hypocotyl) produces about 2.6 times as much CO2 as the endosperm, whereas it absorbs only 1.3 times as much O2.
THE CONVERSION OF FAT TO CARBOHYDRATE IN THE GERMINATING CASTOR BEAN
Authors: Pierce H. B. , Sheldon Dorothy E. , Murlin John R. 
Published: May 2004

1. Analyses for fat (ether extract), protein (N x 6.25), sugar including glucose, crude fiber, and ash have been made on all stages of the germinating castor bean up to 250 mm. length of hypocotyl and root system.
2. There is a continual decrease in the amount of fat present in the whole germinating seedling, and a continual increase in the amount of sugar up to about 40 per cent (dry weight) at a hypocotyl length of 80 to 140 mm., after which it decreases as crude fiber (cellulose) increases. The most rapid decrease in fat content coincides roughly with the most rapid increase of sugar.
3. The carbon balance between fat loss and carbohydrate (including fiber) gain is not at all close, except at the very beginning of growth. An undetermined residue occurs, which increases steadily along with the total carbohydrate and accounts for more and more of the carbon.
4. The protein content which in the ungerminated bean is about 26 per cent, at first falls a little and then rather steadily increases to reach nearly 35 per cent (dry) at the last stages studied. The most plausible explanation of this is the occurrence of more and more volatile substance which is lost in drying.
5. The ash increases irregularly but in the end shows about the same ratio of increase as the protein.
6. Respiration studies on several lots of these beans at different stages of germination exhibited the same low respiratory quotients as reported in Paper I. Comparing their composition at the end of the respiration period with that of corresponding stages when the period began, the chemical change can be compared with the respiratory exchange.
7. A trial balance of all the carbon changes including the respiratory carbon and protein carbon is not very satisfactory, because of our ignorance of the undetermined residue.
8. The respiratory quotient found can be accounted for quite satisfactorily on the assumption that two out of six molecules of ricinoleic acid are converted to cane sugar, one to cellulose, and three are oxidized.
9. The oxygen needed to produce the quantities of known carbohydrate found, added to that used for combustion, and the total subtracted from the observed loss from the respired air yields in two experiments a quantity which, combined with the excess carbon, suggests that the undetermined substance may be an oxidation product of pentose.
ON GUAIACOL SOLUTIONS
Authors: Shedlovsky Theodore , Uhlig Herbert H. 
Published: May 2004

1. Measurements are reported on the distribution of sodium and potassium guaiacolates between guaiacol and water at 25°C.
2. The variation of the partition coefficients with the concentration is explained with the aid of the Debye-Hückel interionic attraction theory and the assumption that the salts are strong electrolytes in water and weak electrolytes in guaiacol.
3. The dissociation constants of sodium and potassium guaiacolates in guaiacol previously computed from electrical conductivity determinations are shown to be in agreement with the corresponding values obtained from the distribution measurements.
4. From theoretical considerations an equation is derived with which it is possible to predict the magnitude of the limiting partition coefficients from the dielectric constants of the solvents, the size of the solute ions, and the temperature.