bluuebunny/crossref_metadata_2025 huggingface dataset:
CHEMICAL ANTAGONISM OF IONS
Authors: Simms Henry S.
Published: May 2004

1.25 per cent gelatin solutions containing enough NaOH to bring them to pH 7.367 (or KOH to pH 7.203) were made up with various concentrations of NaCl, KCl and MgCl2, alone and in mixtures, up to molar ionic strength. The effects of these salts on the pH were observed.

MgCl2 and NaCl alone lower the pH of the Na gelatinate or the K gelatinate, in all amounts of these salts.

KCl first lowers the pH (up to 0.01 M K+), then raises the pH.

Mixtures of NaCl and KCl (up to 0.09 M of the salt whose concentration is varied) raise the pH; then (up to 0.125 M Na+ or K+) lower the pH; and finally (above 0.125 M) behave like KCl alone.

Mixtures of MgCl2 and NaCl raise the pH up to 0.10 M Na+, and lower it up to 0.15 M Na+ regardless of the amount of MgCl2. Higher concentrations of NaCl have little effect, but the pH in this range of NaCl concentration is lowered with increase of MgCl2.

Mixtures of MgCl2 and KCl behave as above described (for MgCl2 and NaCl) and the addition of NaCl plus KCl to gelatin containing MgCl2 produces essentially the same effect as the addition of either alone, except that the first two breaks in this curve come at 0.07 M and 0.08 M [Na+ + K+] and there is a third break at 0.12 M.

In this pH range the free groups of the dicarboxylic acids and of lysine are essentially all ionized and the prearginine and histidine groups are essentially all non-ionized. The arginine group is about 84 per cent ionized. Hence we are studying a solution with two ionic species in equilibrium, one with the arginine group ionized, and one with it non-ionized.

It is shown that the effect of each salt alone depends upon the effect of the cation on the activity of these two species due to combination. The anomalous effects of cation mixtures may be qualitatively accounted for if one or both of these species fail to combine with the cations in a mixture in proportion to the relative combination in solutions of each cation alone.

Special precautions were taken to ensure accuracy in the pH measurements. The mother solutions gave identical readings to 0.001 pH and the readings with salts were discarded when not reproducible to 0.003 pH. All doubtful data were discarded.
CHEMICAL AND PHYSICAL CHANGES IN GELATIN SOLUTIONS DURING HYDROLYSIS
Authors: Northrop John H.
Published: May 2004

1. The change in viscosity and the corresponding increase in the carboxyl groups, as determined by the formol titration, has been determined in gelatin solutions during the progress of hydrolysis by pepsin.

2. Very marked changes in viscosity are found to result from very slight chemical changes. If the viscosity is increased by the addition of acid a greater change in viscosity (volume of solute) is caused by the same percentage change in the number of carboxyl groups. The percentage change in the volume of solute, caused by the same percentage increase in the number of carboxyl groups, is independent of the concentration of gelatin.

3. These results are in agreement with the idea that the high viscosity of gelatin solutions is due to the presence of swollen micells, since a slight chemical hydrolysis may be sufficient to rupture a micella and so cause a very large change in viscosity.
THE EFFECT OF VALENCE OF IONS ON CELLULAR PERMEABILITY TO WATER
Authors: Lucké Balduin , McCutcheon Morton
Published: May 2004

1. Permeability to water in unfertilized eggs of the sea urchin, Arbacia punctulata, was studied by measuring the rate of swelling in hypotonic dextrose solution.

2. Permeability is greatly affected by addition of electrolytes in low concentration.

3. A decrease in permeability to water was found with increasing valence of the cation, using a series of cobaltammine chlorides in which the valence of the cation ranged from 1 to 6.

4. Conversely, an increase in permeability to water was found with increasing valence of the anion, using two series of potassium salts in which the valence of the anion ranged from 1 to 4, and 1 to 3, respectively.

5. It is concluded that the effect of electrolytes on permeability to water depends chiefly on the sign and the number of charges on the ion, in the sense that positive ions decrease permeability to water, while negative ions increase permeability to water; and the effectiveness of the ion is greater the higher its valence.

6. Antagonism has been demonstrated between cations and anions in their effect on permeability, and the method employed permits quantitative study of such antagonism.
ON PYRIDINE HEMOCHROMOGEN
Authors: Mirsky A. E. , Anson M. L.
Published: May 2004

1. Cyanide hemochromogen probably contains one cyanide group per heme group.

2. The equilibrium between pyridine hemochromogen and its components, pyridine and reduced heme, is complicated to an unknown extent by the precipitation of reduced heme and the aggregation of pyridine hemochromogen.

3. These complications were not taken into account in R. Hill's experiments on pyridine hemochromogen.

4. Even if Hill's experiments are sound they do not prove his conclusion that pyridine hemochromogen contains two pyridine groups per heme group.
PHOTOSYNTHESIS AS A FUNCTION OF LIGHT INTENSITY AND OF TEMPERATURE WITH DIFFERENT CONCENTRATIONS OF CHLOROPHYLL
Authors: Emerson Robert
Published: May 2004

1. Photosynthesis reaches its maximum rate at about the same light intensity over the whole range of chlorophyll concentrations studied.

2. Over this range the process shows the same relationship to temperature. The value of the temperature characteristic decreases gradually as the temperature rises.

3. The rate of photosynthesis is more depressed by prussic acid the lower the chlorophyll concentration.

4. These results are interpreted as indicating that photosynthesis possibly involves an autocatalytic reaction, and that chlorophyll must play some part in the process in addition to its rôle in the absorption of light.
THE VALIDITY OF THE GLASS ELECTRODE IN AMMONIUM CHLORIDE BUFFERS
Authors: Hill Samuel E.
Published: May 2004

It is shown that the glass electrode may be used without appreciable error to measure pH of ammonia or ammonium chloride buffers, but that corrections must be applied above pH 8.6 if sodium ions are present in the unknown solution. Corrections are given for values from pH 8.6 to 9.4. A slight further modification of form of glass electrode used by previous workers is described.
THE MECHANISM OF COMPLEMENT FIXATION
Authors: Eagle Harry
Published: May 2004

1. Complement fixation is obtained in every antigen-antibody reaction involving the presence or formation of a heterogeneous phase (red cells, bacteria, precipitate).

2. The physical constants of fixation (temperature coefficient, velocity, quantitative relationships between the reactants) are those commonly associated with adsorption processes, and are the same in the three types of fixation studied.

3. All the in vitro immune reactions involve an aggregation of immune-serum globulins upon the surface of the antigen. It has been shown that the "fixation" of complement is an adsorption by the aggregates so formed; whether these aggregates are visible as a flocculent precipitate (e.g., sheep serum vs. anti-serum) or concentrated as a surface film on a cellular antigen (sensitized cells; agglutinated bacteria), the reaction is fundamentally the same.

4. As yet, it is unknown whether this adsorption is determined by the physical state of the precipitate, and thus, differs only quantitatively from that by Kaolin, charcoal, normal bacteria, heat-denatured proteins, etc.; or whether the comparatively enormous avidity of these aggregates for complement is due to a specific chemical affinity.
THE PENETRATION OF LUMINOUS BACTERIA BY THE AMMONIUM SALTS OF THE LOWER FATTY ACIDS
Authors: Hill Samuel E.
Published: May 2004

It is shown that disappearance of the light of luminous bacteria may be used as a criterion of cell penetration; that luminous bacteria are cytolyzed by water, hypotonic solutions, and by freely penetrating solutions; that luminous bacteria are not injured by hydrogen or hydroxyl ions in the external solutions within the range of pH values employed with the ammonium salts and that therefore disappearance of the light in isotonic solutions of these salts must be due to penetration of the solute; and that there is a characteristic difference between the effects of strong and of weak acids and alkalies on luminous bacteria.
UNEQUAL DISTRIBUTION OF IONS IN A COLLODION CELL
Authors: Northrop John H.
Published: May 2004

The properties of dry collodion membranes previously described allow the prediction that cells of these membranes will concentrate solutes under certain conditions. Three such cases have been studied experimentally.

1. A membrane containing thiosulphate and immersed in a solution of iodine concentrates iodide ion.

2. A membrane containing sodium chromate and immersed in mercury chloride concentrates chloride ion.

3. A membrane containing calcium carbonate and immersed in acetic acid concentrates acetate ions.
THE RESPIRATION OF LUMINOUS BACTERIA AND THE EFFECT OF OXYGEN TENSION UPON OXYGEN CONSUMPTION
Authors: Shoup Charles S.
Published: May 2004

1. The respiration of luminous bacteria has been studied by colorimetric and manometric methods.

2. Limulus oxyhaemocyanin has been used as a colorimetric indicator of oxygen consumption and indicator dyes were used for colorimetric determination of carbon dioxide production.

3. The Thunberg-Winterstein microrespirometer has been used for the measurement of the rate of oxygen consumption by luminous bacteria at different partial pressures of oxygen.

4. The effect of oxygen concentration upon oxygen consumption has been followed from equilibrium with air to low pressures of oxygen.

5. Luminous bacteria consume oxygen and produce carbon dioxide independent of oxygen pressures from equilibrium with air (152 mm.) to approximately 22.80 mm. oxygen or 0.03 atmosphere.

6. Dimming of a suspension of luminous bacteria occurs when oxygen tension is lowered to approximately 2 mm. Hg (0.0026 atmosphere) and when the rate of respiration becomes diminished one-half.

7. Pure nitrogen stops respiratory activity and pure oxygen irreversibly inhibits oxygen consumption.

8. The curve for rate of oxygen consumption with oxygen concentration is similar to curves for adsorption of gasses at catalytic surfaces, and agrees with the Langmuir equation for the expression of the amount of gas adsorbed in unimolecular layer at catalytic surfaces with gas pressure.

9. A constant and maximum rate of oxygen consumption occurs in small cells when oxygen concentration becomes sufficient to entirely saturate the surface of the oxidative catalyst of the cell.
THE SIZE OF BACTERIA AS THE CAUSE OF THE LOGARITHMIC ORDER OF DEATH
Authors: Rahn Otto
Published: May 2004

Death of unicellular organisms is brought about by the inactivation of a certain number of essential molecules in the cell.

If the number of these essential molecules is only one per cell, the order of death is the same as if the cell were identical with this molecule; the order of death is logarithmic following the mass law.

If more than one molecule must be inactivated before the cell dies, the order of death is not logarithmic. With 2 or 3 molecules, it still resembles the logarithmic order, but with an increasing number of reacting molecules, it approaches more and more the order of death known with higher organisms, namely a period of no death, followed by a comparatively short period of rapid death.

The decision whether or not the logarithmic order exists, should be based upon the constancy of the death rate

See PDF for Equation.

The existence of a straight line when logarithms of survivors are plotted against time, is not sufficient proof unless the initial number of cells is included.

These deductions are made with the assumption that all organisms are exactly alike, and show no individual variations or graded resistance.

With most bacteria, the order of death is so nearly logarithmic that death must be brought about by the inactivation of only one molecule, though there may be several molecules of this same type in each cell.
DISSIMILARITY OF INNER AND OUTER PROTOPLASMIC SURFACES IN VALONIA. II
Authors: Damon E. B.
Published: May 2004

In measurements of P.D. across the protoplasm in single cells, the presence of parallel circuits along the cell wall may cause serious difficulty. This is particularly the case with marine algae, such as Valonia, where the cell wall is imbibed with a highly conducting solution (sea water), and hence has low electrical resistance. In potential measurements on such material, it is undesirable to use methods in which the surface of the cell is brought in contact with more than one solution at a time. The effect of a second solution wetting a part of the cell surface is discussed, and demonstrated by experiment.

From further measurements with improved technique, we find that the value previously reported for the P.D. of the chain

Valonia sap | Valonia protoplasm | Valonia sap

is too low, and also that the P.D. undergoes characteristic changes during experiments lasting several hours. The maximum P.D. observed is usually between 25 and 35 mv., but occasionally higher values (up to 82 mv.) are found.

The appearance of the cells several days after the experiment, and the P.D.'s which they give with sea water, indicate that no permanent injury has been received as a result of exposure to artificial sap. If such cells are used in a second measurement with artificial sap, however, the form of the P.D.-time curve indicates that the cells have undergone an alteration which persists for a long time.

On the basis of the theory of protoplasmic layers, an attempt has been made to explain the observed changes in P.D. with time, assuming that these changes are due to penetration of KCl into the main body of the protoplasm.
NOTE ON THE VARIATION WITH TEMPERATURE OF THE RELATIVE RATES OF HYDROLYSIS OF GLUCOSIDES
Authors: Moelwyn-Hughes Emyr Alun
Published: May 2004

Attention is drawn to the necessity of taking the values of the critical increments into account when the velocity constants for reactions of any pair of glucosides are compared. The ratio of the velocity coefficients for the hydrolysis of any two glucosides, determined at the same temperature, varies with temperature except in the special case when both hydrolyses have the same critical increment. Different values given by various investigators for the same ratio are shown to be due to the fact that comparative experiments have been carried out at different temperatures with two glucosides possessing different critical increments of hydrolysis. In the light of these considerations it becomes necessary to revise certain deductions which have been drawn from the comparison of rates of hydrolysis of glucosides by acids (at fairly high temperatures) with the rates of hydrolysis of glucosides by enzymes (at relatively low temperatures).
OXIDATION-REDUCTION POTENTIALS AND THE POSSIBLE RESPIRATORY SIGNIFICANCE OF THE PIGMENT OF THE NUDIBRANCH CHROMODORIS ZEBRA
Authors: Preisler Paul W.
Published: May 2004

1. Oxidation-reduction potential methods have been applied to a study of the blue-purple pigment present in solution in the blood and in the tissue cells of the nudibranch Chromodoris zebra.

2. The blue-purple pigment and its yellow reduction product form a reversible system whose Eo' = x0.102 volts at pH 7.0 and whose valence change from oxidant to reductant appears to be one.

3. The system is unlike oxyhemoglobin-hemoglobin in the mode of oxygen transfer. Its rôle as a possible respiratory material is discussed.
THE DIRECT CURRENT RESISTANCE OF VALONIA
Authors: Blinks L. R.
Published: May 2004

A direct current bridge with vacuum tube detector is described for measuring the resistance of living cells. Methods for evaluating the surface of contact with the protoplasm, and the leakage around the cell wall, allow us to calculate the effective resistance of the protoplasm. In Valonia ventricosa this is usually at least 10,000 ohms per square centimeter and is often much higher. This is in agreement with the very slight ionic interchange observed in normal Valonia.
THE PERMEABILITY OF THE SURFACE OF MARINE ANIMALS
Authors: Bethe Albrecht
Published: May 2004

The surfaces of all marine invertebrates which have been experimented upon are permeable for water and also for both the salts or their ions which are in solution in their blood and in sea water. The forces which tend to bring the salt content of the blood into equilibrium with the salt content of the surrounding sea water are just as great as the forces which strive to prevent osmotic differences. The skin of these animals, save in the cases where special modifications have arisen, serves only as a protecting barrier preventing the loss of the body colloids.
A METHOD FOR THE QUANTITATIVE ESTIMATION OF BACTERIA IN SUSPENSIONS
Authors: Krueger Albert P.
Published: May 2004

A method is described for estimating the cell concentration of bacterial suspensions by measurement of the column lengths of packed cells centrifuged into a capillary tube of fine bore. The total error, under the experimental conditions employed, checked by direct count, was >2 per cent for dense suspensions and about 5 per cent for light suspensions. The method is suitable for work requiring rapid and accurate routine preparation of bacterial suspensions of known cell concentrations.
A METHOD FOR THE QUANTITATIVE DETERMINATION OF BACTERIOPHAGE
Authors: Krueger Albert P.
Published: May 2004

1. In the case of the staphylococcus and antistaphylococcus phage studied, with the total volume of the mixture being kept constant, there exists a definite quantitative relationship between CPhage and the time required to reduce a particular concentration of growing phage-susceptible bacteria to an arbitrary turbidity end-point.

2. This relationship furnishes a basis for the quantitative estimation of bacteriophage. A method is described having an accuracy within ±5 per cent.
THE KINETICS OF PENETRATION
Authors: Jacques A. G. , Osterhout W. J. V.
Published: May 2004

The rate of penetration of CO2 into living cells of Valonia has been studied at high and low pH values.

The time curve of penetration appears to be of the first order but with a "velocity constant" which falls off from the start.

The evidence indicates little penetration of ions. This is shown by (a) the similarity of velocity "constants" at high and low pH values, (b) the rate of penetration, which remains constant as long as the external concentration of undissociated CO2 remains constant no matter how much the concentration of ions varies.
CALCULATIONS OF BIOELECTRIC POTENTIALS
Authors: Osterhout W. J. V.
Published: May 2004

The P.D. of 0.01 M vs. 0.001 M KCl (concentration effect) in Nitella is 54.7 mv. and that of NaCl is 20.9 mv. The P.D. of 0.01 M NaCl vs. 0.01 M KCl is 82.9 mv.

If we assume that diffusion potentials predominate we may calculate the relative mobilities of the ions in the outer layer of the protoplasm. If we put vCl = 1 we obtain uK = 85.45 and uNa = 2.18. (These values depend upon the fact that the mean ionic activities in this layer must be equal at equilibrium to the mean ionic activities in the external solution.)

Using these values the calculated P.D. of 0.01 M NaCl vs. 0.005 M NaCl + 0.005 M KCl is 66 mv. (the observed value is 68.8 mv.) and the conductance of KCl in the outer layer of the protoplasm is 27 times as great as that of NaCl (the observed conductance for the whole protoplasm is 25 to 50 times greater for KCl than for NaCl).

Calculations on the basis of phase boundary potentials are less satisfactory.
THE CELL SAP OF HALICYSTIS
Authors: Blinks L. R. , Jacques A. G.
Published: May 2004

Analysis was made of 25 cc. of vacuolar sap, obtained from over 300 cells of Halicystis collected in their position of growth in Bermuda. The determinations agree very well with those of the stranded cells, except that there is even less potassium present. The K:Na ratio is 0.0114.
THE VARIATION OF ELECTRICAL RESISTANCE WITH APPLIED POTENTIAL
Authors: Blinks L. R.
Published: May 2004

Many of the freshly gathered cells of Valonia ventricosa have a resistance to direct current which is variable and depends on the potential applied. It is low when low potentials are applied and rises sharply at higher values. The rise may be more than 100 per cent in the cell as a whole, which is equivalent to several hundred per cent in the protoplasm alone. The rise becomes less as the cells stand in the laboratory, until a maximum is reached at all applied potentials, low and high, below the breakdown value (about 100 mv.): the cells are then said to be in a constant state.

During the variable state, the resistance rises when the positive current enters the protoplasm from outside, and falls when it passes out from the vacuole (this is determined by killing one end with chloroform).

The rise of resistance becomes faster with closely succeeding applications of potential. This is ascribed to the removal from the protoplasm of ions to which it is reversible. There is some evidence that these may be potassium ions.

Much of the apparent resistance rise may be accounted for by a back E.M.F. caused by the flow of current.
THE VARIATION OF ELECTRICAL RESISTANCE WITH APPLIED POTENTIAL
Authors: Blinks L. R.
Published: May 2004

Electrical resistance and polarization were measured during the passage of direct current across a single layer of protoplasm in the cells of Valonia ventricosa impaled upon capillaries. These were correlated with five stages of the P.D. existing naturally across the protoplasm, as follows:

1. A stage of shock after impalement, when the P.D. drops from 5 mv. to zero and then slowly recovers. There is very little effective resistance in the protoplasm, and polarization is slight.

2. The stage of recovery and normal P.D., with values from 8 to 25 mv. (inside positive). The average is 15 mv. At first there is little or no polarization when small potentials are applied in either direction across the protoplasm, nor when very large currents pass outward (from sap to sea water). But when the positive current passes inward there is a sudden response at a critical applied potential ranging from 0.5 to 2.0 volts. The resistance then apparently rises as much as 10,000 ohms in some cases, and the rise occurs more quickly in succeeding applications after the first. When the potential is removed there is a back E.M.F. displayed. Later there is also an effect of such inward currents which persists into the first succeeding outward flow, causing a brief polarization at the first application of the reverse potential. Still later this polarization occurs at every exposure, and at increasingly lower values of applied potentials. Finally there is a "constant" state reached in which the polarization occurs with currents of either direction, and the apparent resistance is nearly uniform over a considerable range of applied potential.

3. A state of increased P.D.; to 100 mv. (inside positive) in artificial sap; and to 35 or 40 mv. in dilute sea water or 0.6 M MgSO4. The polarization response and apparent resistance are at first about as in sea water, but later decrease.

4. A reversed P.D., to 50 mv. (outside positive) produced by a variety of causes, especially by dilute sea water, and also by large flows of current in either direction. This stage is temporary and the cells promptly recover from it. While it persists the polarization appears to be much greater to outward currents than to inward. This can largely be ascribed to the reduction of the reversed P.D.

5. Disappearance of P.D. caused by death, and various toxic agents. The resistance and polarization of the protoplasm are negligible.

The back E.M.F. of polarization is shown to account largely for the apparent resistance of the protoplasm. Its calculation from the observed resistance rises gives values up to 150 mv. in the early stages of recovery, and later values of 50 to 75 mv. in the "constant" state. These are compared with the back E.M.F. similarly calculated from the apparent resistance of intact cells.

The electrical capacitance of the protoplasm is shown by the time curves to be of the order of 1 microfarad per cm.2 of surface.
THE EFFECT OF LOW PRESSURES ON CELL OXIDATION
Authors: Cook S. F.
Published: May 2004

1. A method is described for measuring tissue oxidation under reduced barometric pressure.

2. The oxygen uptake of yeast is diminished by low barometric pressures to a greater extent than by a reduction of the partial pressure of oxygen, to a corresponding degree, at atmospheric pressure.

3. This effect of low pressure is not observed with certain in vitro oxidation systems.

4. The anaerobic respiration (carbon dioxide production) of yeast is not at all affected by low pressures.

5. The inhibition of tissue oxidation caused by carbon monoxide is removed by lowering the pressure.
CHEMICAL STIMULATION BY ALCOHOLS IN THE BARNACLE, THE FROG AND PLANARIA
Authors: Cole William H. , Allison J. B.
Published: May 2004

1. The stimulating efficiencies of some normal primary aliphatic alcohols have been determined for the barnacle, the frog, and Planaria, under conditions which do not involve narcosis or simultaneous stimulation by other agents.

2. Concentrations of the successive alcohols necessary to produce a given stimulatory effect vary according to the following geometrical series: 1: a–1: a–2: a–3: a–4: . . . ., where a represents some real number.

3. Within certain limits the relationship between the logarithm of the concentration necessary to produce a given effect and the reciprocal of the reaction time is linear in the frog and in Planaria.

4. The concentration effect may be expressed by an equation which contains one constant characteristic of the alcohol series, and another one characteristic of each member. The ratio of the latter constants for successive alcohols represents a in the above series.

5. The stimulation by alcohols in these animals is considered to be due to energy changes at the receptive surfaces, brought about by a definite orientation of the respective alcohol molecules. Increase in stimulating efficiency as the number of CH2 groups increase must be due to the rôle of the non-polar portion of the alcohol molecule, since the polar group remains practically constant throughout the series.

6. In homologous series of organic compounds it is conceived that stimulating effects will be produced either by the polar group or the non-polar group, according to which one becomes dominant in effect, or to a combination of the two.
FACTORS INFLUENCING THE RESPIRATION OF ERYTHROCYTES
Authors: Wright G. Payling
Published: May 2004

1. The oxygen consumption of normal and "primitive red cells" of fowls' blood has been determined at intervals in the course of an anemia produced by the injection of phenylhydrazine. The "primitive red cells" have an oxygen consumption at least twenty to twenty-five times greater than the normal red cells.

2. Suspension of the cells derived from the blood in anemia in sodium chloride solutions of various concentrations has comparatively little effect upon the oxygen consumption of the cells.

3. The red cells from anemic blood are sensitive to variations in the reaction of the medium in which they are suspended. The maximum oxygen consumption, after addition of a saline solution containing variable amounts of acid to the blood, took place at pH 7.75. They appeared somewhat more sensitive to variations on the acid side of this reaction than on the alkaline.

4. Addition of glucose to the medium increased the oxygen consumption of the cells. Their metabolism in a physiological saline solution containing 0.6 per cent of glucose was 15 per cent higher than in one in which no glucose was present.

5. Certain amino acids in low concentrations had little effect on oxygen consumption, though at higher concentrations some of them definitely diminished it.
FACTORS INFLUENCING THE RESPIRATION OF ERYTHROCYTES
Authors: Wright G. Payling
Published: May 2004

1. The respiration of the reticulocytes of the rabbit has been measured during the period of an anemia produced by phenylhydrazine. Though the respiration increased greatly during the phase of regeneration, the oxygen consumption per billion reticulocytes throughout the period remained approximately the same.

2. The respiration of the reticulocytes was affected by changes in the reaction of the medium in which they were suspended, and was at its maximum about a pH of 8, with a probable intracorpuscular pH of about 7.75.

3. Variations in the tonicity of the suspending medium did not produce any great change in the respiration of the reticulocytes.

4. The presence of glycine, alanine, and glucose in the suspending medium resulted in no acceleration in the respiration of the cells. At higher concentrations glucose tended to depress the respiration. The material oxidized appears to be mainly or entirely contained in the corpuscles at the time they are liberated from the marrow.

5. A comparison is made of the respiration of the reticulated nucleated red cells present in the blood of anemic fowls and the non-nucleated reticulated red cells of rabbits. On the basis of equal volumes of cells, the respiration of the former is about twice that of the latter, while this in turn is about six times as great as the nucleated but non-reticulated normal red cells of the fowl.
THE EFFECT OF SALTS ON THE IONISATION OF GELATIN
Authors: Thimann Kenneth V.
Published: May 2004

The effect of the addition of sodium chloride to gelatin solutions is shown from the Donnan relationship to increase the ionisation of the gelatin, the increase produced in acid solutions reaching a maximum at about 1/1000 molar salt concentration. This effect is attributed to the formation of complex ions.

From the similar action of calcium and copper chlorides the effective combining power of gelatin for complex positive ion formation is deduced. The bearing of complex ion formation on the zwitter-ionic structure and solubility phenomena of proteins is pointed out.
ELECTROMETRIC DETERMINATIONS OF THE DISSOCIATION OF GLYCOCOLL AND SIMPLE PEPTIDES1
Authors: Mitchell Philip H. , Greenstein Jesse P.
Published: May 2004

1. The apparent acid and basic dissociation constants were determined potentiometrically by the methods of hydrolysis and of titration for the following ampholytes: Glycocoll, glycylglycocoll, alanylglycocoll, valylglycocoll, leucylglycocoll, methylleucylglycocoll, phenylalanylglycocoll and glycylglycylglycocoll. The constants were also determined in the presence of KCl and of K2SO4 at equal ionic strength.

2. In general, the relative order of magnitude of the constants decreased as the number of carbon atoms between amino and carboxyl groups increased. An explanation of this is offered on the basis of theories of electronic structure.

3. The application of the modern concepts of solutions to the case of the ampholytic ions is discussed. The inadequacy of the present theories is pointed out.

4. The constants were found, in general, to be functions of the hydrogen ion activity and the ionic strength of the solutions. Apparent contradictions to the Debye-Hückel theory are pointed out and partially explained on the basis of specific ion effects.
THE ACCUMULATION OF ELECTROLYTES
Authors: Osterhout W. J. V.
Published: May 2004

It is suggested that K enters chiefly as KOH, whose thermodynamic potential (proportional to the ionic activity product (aK) (aOH)) is greater outside than within. As this difference is maintained by the production of acid in the cell K continues to enter, and reaches a greater concentration inside than outside. KOH combines with a weak organic acid which is exchanged for HCl entering from the sea water (or its anion is exchanged for Cl-), so that KCl accumulates in the sap.

Na enters more slowly and its internal concentration remains below that of K.

The facts indicate that penetration is chiefly in molecular form.

As the system is not in equilibrium the suggestion is not susceptible of thermodynamic proof but it is useful in predicting the behavior of K, Na, and NH4.
THE ACCUMULATION OF ELECTROLYTES
Authors: Jacques A. G. , Osterhout W. J. V.
Published: May 2004

When 0.001 M NH4Cl is added to sea water containing Valonia macrophysa there seems to be a rapid penetration of undissociated NH3 (or NH4OH) which raises the pH value of the sap so that the thermodynamic potential of KOH becomes greater inside than outside and in consequence K leaves the cell: NaOH continues to go in because its thermodynamic potential is greater outside than inside.

NH4Cl accumulates, reaching a much higher concentration inside than outside. This might be explained on the ground that NH3, after entering, combines with a weak organic acid produced in the cell whose anion is exchanged for the Cl- of the sea water, or (more probably) the organic acid is exchanged for HCl.
THE ORDER OF DEATH OF ORGANISMS LARGER THAN BACTERIA
Authors: Rahn Otto
Published: May 2004

In a previous paper it has been shown that the logarithmic order of death of bacteria can be accounted for by the assumption of some very unstable molecules so essential for reproduction that the inactivation of only one such molecule per cell prevents reproduction and makes the cell appear "dead" according to the standard method of counting living bacteria.

In the present paper dealing with the order of death of larger organisms, only a motile alga, Chlamydomonas, is shown to have the same order of death.

The very scant material on the order of death of yeasts is contradictory. It seems possible that more than one molecule must be destroyed to kill a yeast cell.

With the spores of a mold, Botrytis cinerea, the number of "reacting molecules" is decidedly larger than 1.

A flagellate, Colpidium, gave a survivor curve suggesting the destruction of two molecules before motility ceases. Erythrocytes exposed to ultra-violet light also follow the formula for two reacting molecules.

The analysis of the survivor curves of multicellular organisms is not possible because no distinction between the number of essential molecules and the number of essential cells seems possible. Besides, variability of resistance changes the shape of the survivor curves in such a way that it becomes impossible to differentiate between variability and actual survivor curve.

The general results seem to justify the assumption that in each cell, the number of molecules which are really essential for life and reproduction, is quite limited, and that, therefore, equal cells will not react simultaneously, though ultimately the reaction will be the same.

This theory of lack of continuity in cell reactions owing to the limited number of reacting molecules is an analogon to the quantum theory where continuity ceases because division of matter reaches a limit.

It seems probable that this lack of continuity in cell reactions has a general biological significance reaching beyond the order of death.
A METHOD FOR DETERMINING THE OXYGEN CONSUMPTION OF A SINGLE CELL
Authors: Howland Ruth B. , Bernstein Alan
Published: May 2004

1. A method for measuring the O2 consumption of a single cell is described. The cell is placed in a capillary tube adjacent to a bubble of air. KOH (5 per cent) is drawn in on the opposite side of the air and both ends of the tube are sealed with mineral oil. The decrease in the volume of the gas, representing the O2 consumed, is followed.

2. The possible errors of the technique are appraised.

3. A single Actinosphaerium eichhornii consumes 0.00113 mm.3 of O2 per hour. A single Paramecium caudatum consumes 0.00049 mm.3 of O2 per hour.

4. The significance of the results and the limitations of the method are discussed.
FURTHER STUDIES ON THE KINETICS OF OSMOSIS IN LIVING CELLS
Authors: Lucké Balduin , Hartline H. Keffer , McCutcheon Morton
Published: May 2004

Using unfertilized eggs of Arbacia punctulata as natural osmometers an attempt has been made to account for the course of swelling and shrinking of these cells in anisotonic solutions by means of the laws governing osmosis and diffusion. The method employed has been to compute permeability of the cell to water, as measured by the rate of volume change per unit of cell surface per unit of osmotic pressure outstanding between the cell and its medium.

Permeability to water as here defined and as somewhat differently defined by Northrop is approximately constant during swelling and shrinking, at least for the first several minutes of these processes.

Permeability is found to be independent of the osmotic pressure of the solution in which cells are swelling.

Water is found to leave cells more readily than it enters, that is, permeability is greater during exosmosis than during endosmosis.
METABOLISM AS RELATED TO CHROMOSOME STRUCTURE AND THE DURATION OF LIFE
Authors: Gowen John W.
Published: May 2004

This paper presents the rates of CO2 production for four groups of Drosophila which differ in their chromosome constitutions. The four groups have metabolic rates which correlate with the balance of their chromosomes, the balanced chromosome groups of flies producing less CO2 than the unbalanced chromosome groups. It is concluded therefore that genic balance plays a prominent part in metabolic control.

The carbon dioxide rates are related to the duration of life within these groups. The results show that qualitatively the larger the production of CO2 per day the shorter the time which the flies are capable of living. The agreement is not exact quantitatively. Rubner's theory postulating a limit for the energy an organism is capable of metabolizing does not hold for the six classes of flies. The data show that the theory can be at most not more than a partial truth.

Cell size is found to show no direct correlation with the metabolic rates of the different fly cohorts.
ELECTRICAL VARIATIONS DUE TO MECHANICAL TRANSMISSION OF STIMULI
Authors: Osterhout W. J. V. , Hill S. E.
Published: May 2004

Mechanical stimulation of Nitella often produces responses resembling propagated negative variations but traveling faster and going past a killed spot. They appear to result from a mechanical disturbance traveling along the cell and stimulating each spot it touches (i.e. the stimulus itself travels). They are called mechanical variations to distinguish them from propagated negative variations.

A mechanical disturbance may cause an irreversible change (death wave), but in traveling along the cell it may lose intensity and then produce only a reversible response (mechanical variation) which may eventually change to a propagated negative variation.

The all or none law does not apply to incomplete mechanical variations, for the response varies with the strength of the stimulus.
A METHOD FOR THE RAPID DIALYSIS OF LARGE VOLUMES OF PROTEIN SOLUTIONS
Authors: Abramson H. A. , Grossman E. B.
Published: May 2004

A method is described by which moderately large quantities of protein solutions can be dialyzed relatively free of salts within 12 to 24 hours. The use of "Visking" tubes instead of collodion bags is recommended, for speed of dialysis as well as ease of manipulation.
THE OCCURRENCE OF PORPHYRINS IN CULTURES OF C. DIPHTHERIAE
Authors: Coulter Calvin B. , Stone Florence M.
Published: May 2004

A complex porphyrin which has not been hitherto described is found in liquid cultures of C. diphtheriae. The porphyrin is a combination of coproporphyrin with both iron and copper, and shows an oxidation-reduction change. This is the first report, as far as we are able to determine, of a porphyrin compound which contains both iron and copper in its molecule. Its source is in all probability the cytochome of the bacilli.

The content of porphyrin is proportional to the biological titer of the culture filtrate; the suggestion is offered that the toxin itself is derived from cytochrome.
PROTEIN COAGULATION AND ITS REVERSAL
Authors: Anson M. L. , Mirsky A. E.
Published: May 2004

1. The globin prepared from hemoglobin by the acid acetone method is denatured globin.

2. The denaturation and coagulation of globin by acid acetone are reversible.

3. Soluble globin can be obtained from the acid acetone globin even if the globin is first precipitated by trichloracetic acid or heated to 100°C.

4. Hill and Holden's theory that they separated native globin from hemoglobin without any intermediate denaturation is not proven by their experiments.
THE PRODUCTION AND INHIBITION OF ACTION CURRENTS BY ALCOHOL
Authors: Osterhout W. J. V. , Hill S. E.
Published: May 2004

Suitable concentrations of ethyl alcohol (1 to 1.5 M) applied to a spot on a cell of Nitella lower the P.D. enough to cause action currents. The alcohol then suppresses action currents arriving from other parts of the cell and acts as a block. After the alcohol is removed the normal P.D. and irritability return.

Similar experiments on the sciatic nerve and skin of the frog produced only a negative result.
THE ISOELECTRIC POINT OF A STANDARD GELATIN PREPARATION1
Authors: Hitchcock David I.
Published: May 2004

Two samples of a standard gelatin were studied, both prepared according to published specifications and washed free from diffusible electrolytes. The isoelectric point of this material was determined in four ways.

1. The pH values of solutions of gelatin in water approached the limit 4.86 ± 0.01 as the concentration of gelatin was increased.

2. The pH values of acetate buffers were unchanged by the addition of gelatin only at pH 4.85 ± 0.01. This gives the isoionic point of Sørensen, which is the isoelectric point with respect only to hydrogen and hydroxyl ions.

3. Gels of this gelatin made up in dilute HCl or NaOH, or in dilute acetate buffers, exhibited maximum turbidity at pH 4.85 ± 0.03.

4. Very dilute suspensions of collodion particles in 0.1 per cent gelatin solutions made up in acetate buffers showed zero velocity in cataphoresis experiments only at pH 4.80 ± 0.01.

No evidence was found for the assumption that gelatin has two isoelectric points at widely separated pH values.

It is concluded that the isoelectric point of this standard gelatin is not far from pH 4.85.
PROTEIN COAGULATION AND ITS REVERSAL
Authors: Anson M. L. , Mirsky A. E.
Published: May 2004

1. It is possible to prepare crystalline, soluble, heat-coagulable serum albumin from coagulated serum albumin.

2. In the cases so far studied, the more soluble a denatured protein, the more easily its denaturation can be reversed.
SALT EFFECTS ON EGGS AND NAUPLII OF ARTEMIA SALINA L
Authors: Boone Eleanor , Baas-Becking L. G. M.
Published: May 2004

Eggs of Artemia salina L., the brine shrimp, are easily obtainable in large quantities. Ecdysis takes place in two stages: (a) extrusion of the inner membrane, and (b) ecdysis of the nauplius from that membrane. The conditions which allow for the former are much more varied than those for the latter.

Nauplii form in only solutions of a few sodium salts; and, in Mg, Ca, and Sr salts, potassium is very toxic.

The possible environment for the nauplii (1 M total molarity) has been ascertained for chlorides of Na, K, Mg, and Ca.

The facts observed account for the peculiar distribution of the organism.
THE PRESENCE OF A GELATIN-LIQUEFYING ENZYME IN CRUDE PEPSIN PREPARATIONS
Authors: Northrop John H.
Published: May 2004

A protein fraction has been isolated from crude pepsin preparations which is about 400 times as active as crystalline pepsin in the lique-faction of gelatin.

The activity as measured by the digestion of casein, edestin or egg albumin is less than that of crystalline pepsin.

It is more resistant to alkali than the crystalline pepsin.
STUDIES ON MILK SECRETION
Authors: Gowen John W. , Tobey Elmer R.
Published: May 2004

In this paper data are presented on cows receiving no food but having access to all of the water which they wished. The yield and composition of the milk were determined at various times during the periods of starvation. The composition of the milk showed changes which were progressive in the sense that they followed a definite course. They were characterized by a marked lowering in the amount of milk produced, by an increase in the total solids (chiefly an increase in the percentage of fat and ash, with a slight increase in proteins), and by a pronounced decrease in the lactose. The decrease in lactose corresponded with a decrease in the dextrose content of the blood, thereby supporting the conclusion that the lactose of milk has as its precursor dextrose of the blood. All the changes in milk composition during starvation can be directly related to the simultaneous changes in the blood.

The following companion paper on insulin and phloridzin as they affect milk secretion further develops these hypotheses.
THE EFFECT OF RADIATIONS FROM A MERCURY ARC IN QUARTZ ON ENZYMES
Authors: Thompson William R. , Hussey Raymond
Published: May 2004

Amylase in solution is inactivated by the radiations from a mercury arc in quartz, in a manner similar to that previously reported for pepsin. The reaction was followed to a point where more than 88 per cent change had taken place, the course being that of mono-molecular radiochemical change. Apparently, this reaction is due to the influence of ultra-violet radiation alone.
STIMULATION BY HYDROCHLORIC ACID IN THE CATFISH, SCHILBEODES
Authors: Cole William H. , Allison James B.
Published: May 2004

1. The reaction of the catfish, Schilbeodes gyrinus Mitchill, to hydrochloric acid over a wide range of concentrations (from pH 1.82 to pH 6.83) has been studied under experimental conditions which reduced to a minimum all other stimuli.

2. As the [H+J increases within the limits mentioned, the reaction time of the fish decreases. In other words, the rate of the stimulation processes is an increasing function of the hydrogen ion concentration.

3. The effective stimulus is the hydrogen ion, since NaCl solutions of equivalent concentration were not stimulating.

4. Stimulation by hydrochloric acid is therefore correlated with the potential of the cation resulting from dissociation of the acid molecule.
ON THE RATE OF OXYGEN CONSUMPTION BY FERTILIZED AND UNFERTILIZED EGGS
Authors: Whitaker D. M.
Published: May 2004

1. The unfertilized eggs of Fucus vesiculosus, in the dark, consume about 5.2 mm.3 O2 per hour per 10 mm.3 eggs.

2. With an illumination of 100,000 foot candles in photosynthesis they liberate more than twice as much oxygen as they consume.

3. The actively swimming antherozoids or sperm of Fucus consume oxygen at a very high rate: 25.5 mm.3 O2 per hour per 10 mm.3 antherozoids.

4. Immediately following fertilization, in the dark, the Fucus eggs increase the rate of oxygen consumption to about 190 per cent of the prefertilization rate.

5. This rate for fertilized eggs, about 190 per cent, is maintained uniformly for 13 or 14 hours, after which there is a barely perceptible rise until 24 hours (when measurements ceased). At 18°C. 50 per cent of the spores in a population have completed the first cell division about 15 hours after fertilization.
ON THE RATE OF OXYGEN CONSUMPTION BY FERTILIZED AND UNFERTILIZED EGGS
Authors: Whitaker D. M.
Published: May 2004

The rate of oxygen consumption by the eggs of the clam Cumingia decreases following fertilization, resembling in this respect a similar phenomenon of the eggs of the annelid Chaetopterus. The unfertilized Cumingia eggs consume approximately 3.1 mm.3 O2 per hour per 10 mm.3 eggs. The average consumption of fertilized eggs over the period 10–60 minutes after fertilization is 1.4 mm.3 O2 per hour per 10 mm.3 eggs or about 45 per cent of the prefertilization rate.
ON THE RATE OF OXYGEN CONSUMPTION BY FERTILIZED AND UNFERTILIZED EGGS
Authors: Whitaker D. M.
Published: May 2004

1. The rate of consumption of oxygen by unfertilized Nereis eggs is about 1.1 mm.3 O2 per hour per 10 mm.3 eggs.

2. Following fertilization the rate increases to 135 per cent or 145 per cent of the prefertilization rate, and continues to increase for 2 hours (the duration of the measurements).