bluuebunny/crossref_metadata_2025_split huggingface dataset:
On the effect of wear on small mesh wire sieves
Authors: Keen Bernard A. , Haines William B. 
Published: March 2009

A series of measurements of wire diameter, length of side, and area of holes, has
been made on new and used sieves, all of which were originally of the
“100 mesh” size, i.e. the
square holes were supposed to be ·01″ in length of side and the
wire to be ·01″ in diameter. The measurements have been expressed
as frequency curves.In the case of unused sieves woven to the I.M.M. specification, the sieve on the
whole compared well with the specification, but in used sieves the variations
were much greater. The divergence from specification in the new and old sieves
is shown by Tables I and II respectively.In one sieve (No. 2) the holes elongated more in one direction than the other. In
fact in one direction the alteration which has taken place is a contraction
rather than a stretch. This effect was probably connected with the manner in
which the sieve was attached to its metal framework, and also to difference in
tempering of the wires and the tension in weaving.A number of the frequency curves showed double peaks, and the actual observations
showed that there was a systematic distribution of values corresponding to these
two peaks. It is probable that some of the guides in one of the combs through
which the warp wires are led during the weaving were displaced sideways, thus
giving alternate strands of wire and narrow holes. This was particularly the
case in the single weave.
Problems of the transplantation of fertilized ova
Authors: Dowling D. F. 
Published: March 2009

1. The object of this investigation has been to advance knowledge of the methods necessary for the practical application of the transplantation of fertilized ova in cattle.2. The induction of ovulation at any specific time can be produced by squeezing out the corpus luteum per rectum. Oestrus occurs from 2 to 4 days afterwards; this is accompanied by ovulation and the ova so produced are readily fertilized. The onset of oestrus after the expression of the corpus luteum is hastened by previous treatment with P.M.S.3. The induction of multiple ovulations is necessary to produce an augmented supply of fertilized ova, but it is of primary importance that the ova so produced are fertilized, viable and capable of full development. Four methods of doing this have been tested.
Severe experimental hyperthyroidism in the ruminant. II. Physiological effects
Authors: Blaxter K. L. 
Published: March 2009

SUMMARY1. The physiological effects of severe hyperthyroidism on five sheep are described.2. Increases in pulse rate of more than 100% were observed. The increase in pulse rate was proportional to dosage with the exception of one sheep which had lesions on the chordae tendinae of the left ventricle.3. The heart, even though beating at this elevated rate, reacted normally to severe exercise, but there was a tendency for the sheep to carry out its normal functions at a slower rate so such large increases in pulse rate did not occur as the result of voluntary activity.4. Considerable cardiac arrhythmia was noticed in all hyperthyroid sheep.5. The relative increases in pulse rate of the cow and the sheep given iodinated casein of the same potency suggest that as between species dosage of iodinated casein is proportional to ‘metabolic body size’—the between species unit of basal metabolism—rather than to body weight itself. On this basis the stimulation of the sheep was between 1 and 4 times the dosage accepted as normal for the cow.6. Body temperatures increased in the most severely affected animals. Respiratory rates quadrupled in some cases.
Pasture type in relation to live-weight gain, carcass composition, iodine nutrition and some rumen characteristics of sheep II. Carcass composition and the non-carcass components of live weight
Authors: Barton R. A. , Ulyatt M. J. 
Published: March 2009

1. The results of two trials with Romney ewes grazed on perennial rye-grass (P), perennial rye-grass with white clover (P + C), short-rotation rye-grass (S) and short-rotation rye-grass with white clover (S + C) are reported. Chemical and dissection analyses of their carcasses were made and the weights of certain internal organs were obtained.2. It was found that the sheep grazed on the P plots had the lightest carcasses (56·2 and 40·9 lb. in trials I and II, respectively), followed by those on the P + C (70·2 and 59·2 lb.), by those on S (74·7 and 61·2 lb.) and the heaviest carcasses were yielded by sheep from the S + C plots (81·5 and 69·1 lb., respectively).3. The weights of dissectible fatty tissue and chemical fat of the carcasses were related to the carcass weights of the different groups of sheep; the group with the lightest carcass weight had the least fat. The other components of the carcass (protein, water and ash) followed the order for group mean carcass weights except that the S carcasses in trial II had slightly less water, protein and ash than the P + C carcasses. The percentage chemical fat of the S carcasses in trial I was also lower than the P + C carcasses.4. In general, the non-carcass components of live weight (head, feet, skin, liver, mesenteric fat, omental fat, kidneys, stomach empty, and intestines empty) all followed the same pattern of increasing weight (P < P + C < S < S + C).
A comparison of litter-mate pigs slaughtered at 200 and 260 lb. live weight
Authors: Braude R. , Townsend M. Jill , Harrington G. 
Published: March 2009

1. A co-ordinated trial has been carried out at eight centres to compare the performance of group-fed pigs slaughtered at about 200 lb. live weight (bacon weight) with that of litter-mates slaughtered at 260 lb. (heavy pigs).2. The bacon pigs were fed either ad lib. or restricted according to live weight, while the heavy pigs were all fed ad lib. with one group having the protein supplement withdrawn from the ration after the pigs had reached 140 lb. live weight.3. Growth rate, efficiency of food conversion and carcass quality (based on dissection) data are summarized in Table 5.4. In general, the results indicated that under the conditions that prevailed, and when the leanness of the carcass is the major consideration, the slaughter weight around 200 lb. was preferable to the heavier weight (about 260 lb.) both from the production and economic aspect.
Relative buffer-index values for root saps of some crop plants
Authors: Small J. , Jackson T. 
Published: March 2009

SUMMARY1. Some data are given for the relative buffer-index values of saps from underground parts of wheat, barley, oats, potatoes and turnips.2. The correlation of these values with limits of tolerances of soil-pHranges by the plants is discussed.3. Some possible practical applications for these data are indicated.
The influence of chemical constitution on the toxicity of organic compounds to wireworms
Authors: Tattersfield F. , Roberts A. W. R. 
Published: March 2009

1. The relationship between chemical constitution and toxicity to wireworms of organic compounds is found to be of a twofold nature.2. The general effect of a group of compounds of the same type is directly determined by the chemical constitution of the type. The particular effects of individual members of the groups are limited by their physical properties such as volatility etc., which may be regarded as indirect consequences of their chemical constitution.3. The aromatic hydrocarbons and halides are on the whole more toxic than the aliphatic hydrocarbons and halides. The groups that influence toxicity most when introduced singly into the benzene ring are in order of importance the methylamido (most effective), dimethylamido, hydroxy, nitro, amido, iodine, bromine, chlorine, methyl groups (least effective). But this order is modified in presence of another group; thus when there is a CH3 already present in the ring the order becomes chlorine (side chain), amido, hydroxy, chlorine (ring), methyl. Chlorine and hydroxy groups together give rise to highly poisonous substances considerably more effective than where present separately. The association of chlorine and nitro groups in chloropicrin gives rise to one of the most toxic substances tested. Methyl groups substituted in the amido group of aniline increase toxicity more than if substituted in the ring.
Some experiments on the interaction between soil and dilute acids
Authors: Puri Amar Nath 
Published: March 2009

(1) Removal of chlorine ions by soil from dilute hydrochloric acid solution has been shown to take place under the experimental conditions employed.(2) Interaction between dilute acids and soil (free from carbonates) has been studied. The results show that hydrochloric acid, nitric acid, sulphuric acid, acetic acid, citric acid and phosphoric acid all react with soil. The state of equilibrium between the soil and the acid solution can be satisfactorily expressed by Freundlich's equation. The order of reactivity of the soil towards various acids does not follow any obvious rule.(3) The various soil fractions do not show any fundamental difference in their equilibrium relationship with regard to an acid solution; the order of their power to react with acid following inversely the order of the size of particles in them.(4) The experiments recorded seem to support the view that the interaction between soil and acids is a surface phenomenon.
The nitrogen balance of laying hens
Authors: Willcox J. S. 
Published: March 2009

SummaryA nitrogen balance experiment of ten weeks' duration with two Rhode Island Red laying hens is described.The observed variations in the retention of nitrogen for egg-producing purposes do not appear to be connected with the output of egg nitrogen or with the number of eggs laid in the various egg cycles.The view held by other workers that the nitrogen required for egg production can be largely if not entirely drawn from the food supplied during the laying period is confirmed.The marked storage of nitrogen which has been shown to occur immediately prior to the commencement of egg laying is not repeated during the laying period, and it is suggested that during a period of heavy egg production synthesis of the nitrogenous constituents of the egg proceeds at a fairly uniform rate.
A New Volumetric Method for the Estimation of Sodium
Authors: Blenkinsop A. 
Published: March 2009

1. A volumetric method for the determination of sodium which can be separated as a triple salt (uranium zinc sodium acetate) from mixed solutions is described. The reduction of the uranium with titanous chloride, upon which it depends is shown to be quantitative.2. Calcium, magnesium, and relatively large proportions of potash do not interfere. The procedure for the removal of iron, aluminium and phosphates by gentle ignition is simple and obviates the risk of error by the introduction of sodium as an impurity in the chemical reagents necessary for precipitation methods.3. 0.1 mg. of sodium can be determined accurately.
The Availability of Phosphatic Fertilisers as shown by an Examination Soil Solution and of Plant Growth (With Two Text-figures.)
Authors: Greenhill A. W. 
Published: March 2009

The growth of barley and the phosphate concentration of the soil solution, of the soil cropped and uncropped, were examined simultaneously in pot cultures, after treatment of an acid soil deficient in phosphate, with lime with and without slag or superphosphate.Liming at the rate of half the lime requirement increased the concentration from about 0·7 p.p.m. P2O5 to about 1 p.p.m. and at the rate of twice the lime requirement to over 2 p.p.m. P205. Phosphates depressed the concentration on the lightly limed soils, and on the heavily limed had variable effects. The superphosphate-treated soils showed rather lower concentrations than the slag-treated. Cropping raised the concentration on the lightly limed treatments, but on the heavily limed reduced it on the control and had a variable effect on the phosphate treatments.
Experiments on the use of home-grown foods for milk production: I. The effect of war-time changes in the food supply on the nutrient intake and milk production of dairy cows
Authors: Blaxter K. L. 
Published: March 2009

1. An experiment has been conducted with dairy cows to find the effect on milk production of feeding rations with a high dry-matter content—typical war-time rations.2. It was found that where a ration high in dry matter is fed, the cow tends to refuse food, and a statistically significant fall in milk production results. The correlation between the refusal of food, calculated in terms of starch equivalent, and the fall in milk production was 0·959.3. The factors causing this inability of the cow to consume sufficient food to meet her total nutrient requirements have been considered. It has been concluded that dry-matter consumption is not an adequate method of expressing the amount of food a cow will consume, and that the major factor influencing food consumption is the palatability of the individual foods making up the ration.My thanks are due to Dr S. J. Rowland for chemical analysis of the individual foods used in the experiments.
Biochemistry of water-logged soils. Part IV. Carbon and nitrogen transformations
Authors: Sreenivasan A. , Subrahmanyan V. 
Published: March 2009

1. During the fermentation of water-logged soil containing added substances with different carbon-nitrogen ratios, the reaction first turns slightly acid, but soon returns to the original hydrogen-ion concentration (pH 7·6).2. The quantities of ammonia present in the medium increase up to a point, after which there is steady decrease.3. There is nitrification only in the case of substances with narrow C/N ratios. The production of nitrate generally commences only after about a month, when the vigour of the initial fermentation has subsided and fairly large quantities of ammonia have accumulated in the medium.4. The extent of mineralisation of nitrogen is determined chiefly by the C/N ratio, though in the cases of substances like mahua and lantana the presence of other constituents may also influence the processes. The quantities of mineralised nitrogen present in the soil system generally tend to decrease after about two months.
Aluminium and acid soils
Authors: Line J. 
Published: March 2009

The addition of aluminium salts to culture solutions and to soils will bring about certain changes; these may be summed up as follows:1. A change in the hydrogen ion concentration, which will vary in amount with the original buffer properties of the solution or the soil.2. A change in the buffer properties of the solution or the soil; the hydrogen in concentration of a culture solution containing an aluminium salt will tend to remain more constant than that of a normal culture solution during the period of growth of the plant, when both start at the samepH value.3. Precipitation of soluble phosphate as aluminium phosphate except in solutions or soils more acid thanpH 3·5 to 4·0; this might lead to phosphate starvation in water cultures but would have little or no effect in a soil, where the particles would remain accessible to the plant roots.
Investigations into the Intensive System of Grassland Management. By the Agricultural Research Staff of Imperial Chemical Industries, Limited. III. The Seasonal Variation in the Mineral Content of Pasture with Particular Reference to Drought.
Authors: Ferguson W. S. 
Published: March 2009

Seventeen samples of pasture collected from May to December, 1929, have been analysed for mineral constituents.1. The results show that drought conditions seriously affect the mineral composition of pastures.2. The calcium content showed a slight fall during the months of drought, and a more marked fall in the months of heavy rain from October to December.3. The phosphorus content fell during the drought period and rose rapidly at the end of the year.
The apparent digestibility of the non-nitrogenous fraction of pig feeds
Authors: Glover J. , Dougall H. W. 
Published: March 2009

A simple method for the estimation of the digestible non-nitrogenous fraction of normal pig feeds is described. It requires only knowledge of the digestibility coefficient of the crude protein contained in the dry matter of the feed.More accurate estimates can be obtained by applying to this method a simple correction involving only the crude protein content of the dried feed. Attention is drawn to the intimacy of the relationship between the digestibilities of the non-nitrogenous and nitrogenous components of the diet.
Minimum mineral requirements in cattle
Authors: Theiler A. , Green H. H. , Toit P. J. Du 
Published: March 2009

1. Records are offered of year old cattle reared to adult weight on rations of varying content in respect to calcium, phosphorus, sodium, potassium and chlorine. Minimal requirements for growth are higher in the case of phosphorus than in the case of calcium, and a ratio of P2O5to CaO so high as three to one is not necessarily disadvantageous. Sodium requirements for growth are very low, 2 gm. Na2O being more than sufficient. Chlorine requirements are below 5 gm. per day. A relatively high ratio of potassium to sodium is not productive of specific disease. There is no good reason to suppose that excess of basic over acidic constituents is necessary in a dietary, and cattle can grow normally to full adult weight when the usual alkaline reaction of the urine is shifted to the acid side.2. Explanation of certain observed abnormalities in calving is left open, except in the case of phosphorus deficiency, in which definitely abnormal calves may be born.3. “Aphosphorosis,” or clinically recognisable phosphorus deficiency disease, is experimentally produced, and shown to be identical with the naturally occurring South African disease Styfsiekte.4. The chemical composition of the milk of animals suffering from aphosphorosis meed not mecessarily be abnormal, but the “inorganic” fraction of the blood may drop to a quarter of the normal value even before the disease can be diagnosed clinically. Other phosphorus compounds of the blood remain normally high. Blood calcium remains practically normal.5. Vitamine deficiency of the diets had no adverse effect. Exogenous requirements of cattle for vitamines A, B, and C are so low that they are covered by a few pounds of poor quality roughage, and therefore do not enter into consideration under any natural system of cattle rearing.
The specific conductivities of soil extracts
Authors: Wright C. H. 
Published: March 2009

1. Considerable differences were found in the specific conductivities of different soils at any one time of the year, and considerable differences in any one soil at different times of the year, the specific conductivities being highest in March and lowest in June and July. Hence it is only possible to compare different soils when samples of these soils are taken at the same time of the year.2. A relation has been found between the specific conductivities of the soil extracts and the mean weights of lint per plant per row in the case of 2 strains of Ishan cotton. Other data are presented showing that the specific conductivity of a 1 to 5 soil extract is an index of the fertility of the soil.3. It has been found that the specific conductivity of a soil decreases under continuous cultivation. There is evidence that the rate of solution also decreases under the same condition.
The mechanical analysis of heavy ferruginous soils
Authors: Groves Ruby C. 
Published: March 2009

Certain heavy ferruginous soils do not respond to the usual preliminary treatment with hydrogen peroxide for mechanical analysis by the pipette method.A method of preliminary treatment is described, involving the use of ammoniacal hydrogen peroxide and repeated gentle rubbing with a rubber pestle which appears to give a satisfactory dispersion with such soils.The results are not affected by mechanical shaking, which may therefore be omitted.
Nutritive value of pasture. III. The influence of the intensity of grazing on the composition and nutritive value of pasture herbage (Part I)
Authors: Woodman H. E. 
Published: March 2009

The present investigation was undertaken with the object of ascertaining the effect of cutting at fortnightly instead of weekly intervals on the yield of pastures, and on the composition, digestibility and nutritive value of the herbage.The main trial was carried out on the 1925 light-land pasture. The plot was divided into 14 sub-plots, and one sub-plot was mown per day. The whole plot, therefore, was cut over once per fortnight during the season. The results in respect of yield, composition and nutritive value were compared with corresponding results obtained on the same pasture plot under a system of weekly cuts during 1925.A second trial was carried out on sub-plots 2 and 3 of the 1926 heavy-land pasture, one sub-plot being cut weekly and the other fort-nightly. The work in this case was restricted to securing comparative data in respect of yield and composition of herbage.The results from both trials lead to the conclusion that the differences in chemical composition, both organic and inorganic, between pasture grass cut at weekly and fortnightly intervals are inconsiderable. The dry matter of the fortnightly-cut grass is extremely rich in crude protein and contains, in comparison with grass cut at the hay stage of maturity, a low percentage of crude fibre. Moreover, these characteristics are retained, by systematic cutting at fortnightly intervals, over the entire season.The results of the digestion trials justify the conclusion that the dry matter of the pasture herbage grown under a system of fortnightly cutting is a protein concentrate equal in digestibility and nutritive value to that obtained by weekly cutting. There is no significant running off in respect of composition and feeding value during the second week of growth. At the end of a fortnight the herbage still consists of the same immature, non-lignified. tissue as it was at the end of a week's growth.
Digestibility trials with poultry: VII. On the influence of the size of a ration upon its digestibility
Authors: Halnan E. T. 
Published: March 2009

1. Four White Leghorn cockerels were fed with widely varying quantities of a Sussex ground oats and milk mixture without material alteration in the coefficients of digestibility of the digestible nutrients.2. The amounts fed varied from a sub-maintenance ration of 50 gm. to a “limit of appetite” ration of 150 gm. A slight depression in the coefficients of digestibility of the organic matter, the crude protein and the N-free extract, and a slight increase in the coefficient of digestibility of the ether extract was obtained, but the differences shown are attributed to normal fluctuations in digestibility due to individual variation and not to differences in the quantity of food given.3. In feeding experiments carried out with fowls, in which variable amounts of food are fed, these experiments indicate that it may safely be assumed that the coefficients of digestibility of the food nutrients are not materially affected by the variations in the amounts of food fed.
Experiments on growing sugar beet under continuous illumination. III. The production of a seed crop in the field and the resolution of a heterogeneous population
Authors: Bell G. D. H. , Bauer A. B. 
Published: March 2009

1. Experiments are described demonstrating a technique for raising sugar beet seedlings under glass during the winter to provide plants for seed production after transplanting into the field.2. The use of 24 hr. illumination for this purpose is discussed, and the effect of this illumination in resolving a heterogeneous population is described.3. The association between the growth habit of the seeding plant and root characters, glomerule yield, weight and size, and the time of anthesis is considered in relation to the recognition of types showing B. maritima and B. vulgaris characteristics.