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Teleseismic Recording In Iowa, Mrs. M. M. Seeburger
Teleseismic Recording In Iowa, Mrs. M. M. Seeburger
Proceedings of the Iowa Academy of Science
The Des Moines Seismograph Station started operation December 20, 1934, using a single component to record east-west motion. On March 15, 1935, a second instrument was placed in operation to record north-south motion.
The Address Of The President: This Changing World, Edward Bartow
The Address Of The President: This Changing World, Edward Bartow
Proceedings of the Iowa Academy of Science
In this address it is my purpose to express some ideas concerning the Changing World of education, science and invention.
Further Studies On Lactation And Rearing Of Young, J. F. Feaster, Victor E. Nelson
Further Studies On Lactation And Rearing Of Young, J. F. Feaster, Victor E. Nelson
Proceedings of the Iowa Academy of Science
The work performed in this laboratory and elsewhere during the past fifteen years has shown conclusively that a diet adequate for growth may not necessarily fulfill the requirements for lactation. The excellent work of Evans and Bishop (1) has conclusively demonstrated that a specific vitamin is required for reproduction. The fact that lactation is not normal on many synthetic and even natural diets suggests the possibility that all of the factors necessary for normal development are not known. The work in this paper was planned in order to increase our knowledge concerning the nutritional factors involved in milk secretion and …
The Alkaline Mercerization Of Wool, Mildred Barr, Rachel Edgar
The Alkaline Mercerization Of Wool, Mildred Barr, Rachel Edgar
Proceedings of the Iowa Academy of Science
The mercerization of a plain-woven wool fabric by treatment with 16, 29, 38, and 44 per cent sodium hydroxide for five minutes at l5°C. has been followed by determination of the weight, nitrogen, sulfur, and breaking strength of the residual fabric.
An Investigation Of The Formation And Excitation Of The Mercury Hydride Molecule Through Resonance Radiation, Leonard O. Olsen
An Investigation Of The Formation And Excitation Of The Mercury Hydride Molecule Through Resonance Radiation, Leonard O. Olsen
Proceedings of the Iowa Academy of Science
A weak excitation by collisions of several of the HgH bands belonging to the electronic system 2π → 2Σ was detected. It was found that HgH was formed in the 2π½ and 2π3/2 (excited) states through a collision process involving Hg 63P and the H2 molecule, one Hg 63P atom dissociating the H2 molecule and a second Hg 63 atom uniting with an H atom to form the excited HgH molecule.
A Study Of Individualized Instruction At The College Level, Daniel D. Feder
A Study Of Individualized Instruction At The College Level, Daniel D. Feder
Proceedings of the Iowa Academy of Science
With a philosophy that makes paramount the greatest possible growth for each individual student as the background, the Department of French at the University of Iowa has conceived and put into operation a plan of individualized instruction. This plan, in effect since September, 1933, marks the latest development of a comprehensive experimental program which has had continuous growth during the past ten years.
Enzymes In Ontogenesis (Orthoptera): I. Tyrosinase, J. H. Bodine, E. J. Boell
Enzymes In Ontogenesis (Orthoptera): I. Tyrosinase, J. H. Bodine, E. J. Boell
Proceedings of the Iowa Academy of Science
Variations in concentration of tyrosinase throughout the entire embryonic development of the grasshopper, Melanoplus differentialis, have been determined by measuring the oxygen uptake of the tyrosinase-tyrosine reaction with the Barcroft-Warburg apparatus. Tyrosinase activity of eggs at different developmental stages has thus been expressed as the amount of O2 consumed per 100 minute interval at 25 ° C. in the oxidation of a given amount of tyrosine by the enzyme extracted (in phosphate buffer pH 8.0) from 20 eggs.
The Zernike And Prins Method Of Computing X-Ray Diffraction Intensities In Liquids, Donald O. Holland, G. W. Stewart
The Zernike And Prins Method Of Computing X-Ray Diffraction Intensities In Liquids, Donald O. Holland, G. W. Stewart
Proceedings of the Iowa Academy of Science
A study has been made of the nature of the approximation in the Zernike and Prins formula by using it with an ideal simple cubic crystal. The computations show the following.
New Apparatus For The Measurement Of The Electro Dermal Response, D. U. Greenwald
New Apparatus For The Measurement Of The Electro Dermal Response, D. U. Greenwald
Proceedings of the Iowa Academy of Science
An analysis of the literature on apparatus used to measure electro dermal responses shows that about ten characteristics have been considered important by the majority of investigators.
Diagnosing The Phosphorus Needs Of Soils By Biological Methods, F. B. Smith, P. E. Brown, H. C. Millar
Diagnosing The Phosphorus Needs Of Soils By Biological Methods, F. B. Smith, P. E. Brown, H. C. Millar
Proceedings of the Iowa Academy of Science
It is a well-known fact that the total phosphorus content of a soil is not a measure of the amount of available phosphorous. Some soils that contain a low total phosphorus content may be supplied with sufficient available phosphorus for present crop needs. On the other hand, some soils that contain a relatively high total phosphorus content may be deficient in available phosphorus.
Chromosome Behavior In The Species Cross Lycopersicum Esculentum X L. Pimpinellifolium, L. M. Humphrey
Chromosome Behavior In The Species Cross Lycopersicum Esculentum X L. Pimpinellifolium, L. M. Humphrey
Proceedings of the Iowa Academy of Science
Preliminary studies revealed a distinct difference in size between the chromosomes of the two species of tomatoes, those of L. esculentum being 20-30 percent larger. Pairing and disjunction in the first meiotic division were regular except for occasional univalents in diakinesis. In a more detailed study the following facts were noted. The somatic chromosomes are small rods with median or sub-median constrictions, those of L. esculentum being distinctly larger. At pachytene of meiosis pairing occurs between all sets but there are certain places on certain chromosomes which never become paired but leave loops or free ends. Univalents are sometimes seen …
The Numbers Of Nitrosomonas In Some Variously Treated Iowa Soils, R. H. Walker, A. A. Klingebiel, L. M. Greiner
The Numbers Of Nitrosomonas In Some Variously Treated Iowa Soils, R. H. Walker, A. A. Klingebiel, L. M. Greiner
Proceedings of the Iowa Academy of Science
A study was made of the numbers of Nitrosomonas, bacteria capable of oxidizing ammonia to nitrite, in variously treated soils of the Agronomy Farm at Iowa State College, and of certain other soils of the state. The dilution method, as modified by Wilson for the study of these organisms was employed for making the determinations.
The Performance Of Adults Of Various Grade Levels On Specific Mental Functions, Lyle K. Henry, Arthur L. Snodgrass
The Performance Of Adults Of Various Grade Levels On Specific Mental Functions, Lyle K. Henry, Arthur L. Snodgrass
Proceedings of the Iowa Academy of Science
Test items designed to measure general intelligence, mechanical information and personality balance were selected from the "Motor Vehicle Test," Series I, Revised, of Iowa State College, and administered to 220 Civilian Conservation Corps enrollees.
Effect Of Induced Manual Handicaps On Motor Performance Of A Complex Nature, Laverne Johnson, A. R. Lauer
Effect Of Induced Manual Handicaps On Motor Performance Of A Complex Nature, Laverne Johnson, A. R. Lauer
Proceedings of the Iowa Academy of Science
The question of how much one's ability to drive an automobile would be affected by the loss of an arm has been experimentally studied, under laboratory conditions, and statistically calculated. Comparison is made between manipulative ability, errors, stop signs and other stimuli missed, etc., as well as driving speed using right, left and both hands respectively.
A Bibliography On The Use Of Photoelectric Cells In Plant Investigations, F. M. Turrell, Louis Waldbauer
A Bibliography On The Use Of Photoelectric Cells In Plant Investigations, F. M. Turrell, Louis Waldbauer
Proceedings of the Iowa Academy of Science
The recent appearance of the "sperrschicht" type of photoelectric cell has made possible the improvement of several old instruments and the development of new ones. These have included colorimeters, nephelometers, titration meters, pH meters, counters, illuminometers, spectrophotometers, reflection meters and area meters. Much of the work has been published since 1931 and is distributed widely in journals in the special fields of botany, chemistry, physics, engineering, medicine, etc. The authors have compiled the following bibliography with the hope of bringing together these recent developments in a form usable to plant physiologists and others interested in colorimetric, turbidimetric and various light …
Deposit Of Silica In Acer Saccharinum L., Myrle M. Burk
Deposit Of Silica In Acer Saccharinum L., Myrle M. Burk
Proceedings of the Iowa Academy of Science
Report of a small quartz pebble found imbedded in the wood of Acer saccharinum L.
The Nitrogen, Phosphorus And Organic Carbon Content Of Iowa Soils, P. E. Brown, R. H. Walker
The Nitrogen, Phosphorus And Organic Carbon Content Of Iowa Soils, P. E. Brown, R. H. Walker
Proceedings of the Iowa Academy of Science
During the past 20 years an investigation has been underway to determine the nitrogen, phosphorus and organic carbon content of the various soils of Iowa. Samples were taken of the various soil types mapped in each county and they were then analyzed. A statistical analysis of the results has been made to determine the average nitrogen, phosphorus and organic carbon content of each soil type, and also to determine the significance of the differences between types.
Addition Of Chloroamines To Ketenes, George H. Coleman, Rolf L. Peterson
Addition Of Chloroamines To Ketenes, George H. Coleman, Rolf L. Peterson
Proceedings of the Iowa Academy of Science
Considerable work has been done in this laboratory on the reactions of chlorine derivatives of nitrogen compounds, particularly nitrogen trichloride, monochloroamine, monobromoamine, dibromoamine, and the alkylchloroamines.
Simple Lecture Experiments In A Course On Modern Physics, John A. Eldridge
Simple Lecture Experiments In A Course On Modern Physics, John A. Eldridge
Proceedings of the Iowa Academy of Science
It is maintained that illustrative experiments are as necessary in introductory courses in modern physics as in the elementary general course. These experiments need not be elaborate. Experiments given at the University of Iowa are described.
On The Effectiveness Of Lecture Demonstrations, C. J. Lapp
On The Effectiveness Of Lecture Demonstrations, C. J. Lapp
Proceedings of the Iowa Academy of Science
A long series of experiments have been performed in an attempt to learn the effectiveness of lecture demonstration experiments. Large groups of students have been used whose physics intelligence coefficients were known. Part of the group has been used to hear the lecture while the rest were writing an examination over laboratory work in another part of the building. The results are very disquieting for those who have deep faith in the lecture method.
An Experimental Study Of The Developmental Processes In Art Appreciation, Mildred Dow Voss
An Experimental Study Of The Developmental Processes In Art Appreciation, Mildred Dow Voss
Proceedings of the Iowa Academy of Science
To determine by what processes art appreciation could be increased, two groups of fifty children each from the second, third, and fourth grades were matched for intelligence, mental age, chronological age, socio-economic status, grade, sex, and art appreciation scores. One group served as an experimental group, the other as a control group. Art appreciation was measured by a battery of tests including the following: (1) the McAdory Art Test revised to include only the best and worst choices of each test item; (2) Part I, Section I, on recognition of proportion, of the Lewerenz Tests in Fundamental Abilities of Visual …
The Fate Of Acetylmethylcarbinol And Diacetyl In Dairy Products, G. L. Stahly, B. W. Hammer, M. B. Michaelian, C. H. Werkman
The Fate Of Acetylmethylcarbinol And Diacetyl In Dairy Products, G. L. Stahly, B. W. Hammer, M. B. Michaelian, C. H. Werkman
Proceedings of the Iowa Academy of Science
Butter cultures normally contain two distinct types of bacteria, (a) a typical lactic acid forming type (Streptococcus lactis) and (b) a type which is important from the standpoint of the production of satisfactory flavor and aroma and includes Streptococcus citrovorus and Streptococcus paracitrovorus.
A Growth Factor For Rhizobia, D. W. Thorne, R. H. Walker
A Growth Factor For Rhizobia, D. W. Thorne, R. H. Walker
Proceedings of the Iowa Academy of Science
A study of the nutritional requirements of the root-nodule bacteria has demonstrated the necessity of an accessory factor for their growth. Two species of Rhizobium were studied. They were not able to maintain growth when continuously cultivated in a synthetic medium containing only C. P. chemicals, including mineral salts, a nitrogen source of KNO3 , and sucrose. Upon replacing the C. P. sucrose with commercial cane sugar the organisms were able to grow. Presumably cane sugar contains a factor necessary for the growth of rhizobia. A concentrated preparation of the growth substance was prepared by extracting cane sugar with …
Qualitative Analysis Without Hydrogen Sulfide, Jacob Cornog, Lothrop Smith
Qualitative Analysis Without Hydrogen Sulfide, Jacob Cornog, Lothrop Smith
Proceedings of the Iowa Academy of Science
A system of Qualitative Analysis is presented in which ammonium sulfide instead of hydrogen sulfide is used as a source of sulfide ion.
Mean Free Paths Of Gas Molecules In Mercury Vapor, John A. Eldridge
Mean Free Paths Of Gas Molecules In Mercury Vapor, John A. Eldridge
Proceedings of the Iowa Academy of Science
The mean free paths have been obtained for hydrogen, helium, nitrogen, carbon dioxide, methane, ethane, propane, butane and isobutane through mercury vapor. The decrease in intensity is observed as a beam of the gas passes through the vapor, any deviation as great as a half degree removing the molecules from the beam. The free paths measured in this way are, as is expected, several times smaller than the values determined from viscosity data.
The Myelencephalic Gland Of Lepidosteus (Osseus And Platostomus) And Its Relationship To The Semicircular Canals, Carrie C. Gillaspy
The Myelencephalic Gland Of Lepidosteus (Osseus And Platostomus) And Its Relationship To The Semicircular Canals, Carrie C. Gillaspy
Proceedings of the Iowa Academy of Science
The myelencephalic gland is tri-lobed. The median lobe is wider than any other division of the brain and the width from tip to tip of the lateral lobes is almost as wide again as the median lobe.
Photocells For Laboratory Use, L. E. Pinney
Photocells For Laboratory Use, L. E. Pinney
Proceedings of the Iowa Academy of Science
Cells having various types of composite coatings have been prepared. Particular attention has been given to better insulation and greater stability than is found in commercial cells.
A Physical Apparatus For The Determination Of The Circulation Time Of The Blood In Dogs, E. C. Mccracken
A Physical Apparatus For The Determination Of The Circulation Time Of The Blood In Dogs, E. C. Mccracken
Proceedings of the Iowa Academy of Science
A radical departure from previous apparatus for the determination of blood circulation time is described in detail. The ensemble consists of an ionization chamber (Geiger Counter), a high-voltage (to 2500 volts) power supply, a three-stage amplifying system, and an output circuit for recording the discharges which occur when radiations enter the chamber. A separate electrical circuit is utilized to measure the time interval between the injection of the radioactive material (radium C) in the jugular vein of the dog and its arrival in that part of the femoral artery lying in the adductor canal. The technique of separating radium C …
Embryology And Anatomy Of Iowa Hawks With Special Reference To The Reproductive System, Allan J. Stanley
Embryology And Anatomy Of Iowa Hawks With Special Reference To The Reproductive System, Allan J. Stanley
Proceedings of the Iowa Academy of Science
A comparative study of the reproductive systems of four species of Iowa hawks shows that the right ovary may be entirely lacking or persistent to a degree which may be functional. The right oviduct is either absent or vestigial. An embryological examination of Cooper's hawk shows that there is little or no migration of the primordial germ cells from right to left, as has been reported for other species, notably the English sparrow, the red-winged blackbird and the chick - and correspondingly less asymmetry in the reproductive system. The Falconiformes on this basis are assumed to represent a phylogenetic step …
Metabolic Rate In Relation To Sex In Amphibia (Triturus Torosus), Irvin A. Wills
Metabolic Rate In Relation To Sex In Amphibia (Triturus Torosus), Irvin A. Wills
Proceedings of the Iowa Academy of Science
In the study of the metabolic rate of Amphibia, a careful investigation has been completed for the Californian newt, Triturus torosus. Groups and single individuals have been measured at numerous intervals. The data cover the range of life history from time of early cleavage stages until time of sexual maturity. The metabolic rate is expressed in cubic millimeters of oxygen consumed per milligram of total nitrogen content of the animal per hour. The total nitrogen content of the animal was found to be a better basis of reference rather than surface area or dry weight. The oxygen consumption was measured …