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SUMMARYAn experiment is described in which plots of a silt loam soil were compacted by ploughing and rotary cultivation when the moisture content was high. Kale and barley were grown on these plots in 2 years.Compaction of the soil was not as great as anticipated, but there were marked reductions due to wet cultivation in the dry-matter yield of kale and the vegetative growth of the young barley. Seed yield of barley was relatively unaffected, although there was a significant reduction due to wet ploughing in one year.The implication of these results for experimentation on the effects of soil structure on crop yield are discussed.

Antibodies against the "core" glycolipid of Enterobacteriaceae (2-keto, 3-deoxyoctonate-Lipid A) have been associated with protection against the sequelae of gram-negative rod bacteremia. To investigate the nature of this protection, dogs and rabbits were immunized with purified glycolipid prepared by phenol-chloroform-petroleum ether extraction of the "Re" mutant of Salmonella minnesota 595 and opsonophagocytic and bactericidal tests were carried out using lapine peritoneal granulocytes and serum factors. Whereas 1-4 mug/kg of glycolipid i.v. produced hypotension in dogs and 8 mug/kg i.v. was lethal, a rising dosage schedule of immunization with an average total dose of 1 mg/kg produced striking protection against shock and death against challenge with heterologous organisms. 20 control dogs, given approximately 10(10) live, serum-resistant Escherichia coli 0.85:H9 or Serratia marcescens 03 during a continuous intra-arterial pressure transducer recording, showed a drop in mean systolic pressure from 186 (+/- 6 SE) to 101 (+/- 12 SE) MM Hg and a fall in mean diastolic pressure from 118 (+/- 3 SE) to 64 (+/- 8 SE) mm Hg within 60-120 min. Minor pressure changes (average less than 12% of prechallenge levels) were seen in the same number of immunized dogs. In contrast, no significant difference was noted in the bloodstream clearance of these serum-resistant organisms over a period of 4-6 h between immunized and control dogs. Intravascular clearance was greater in animals immunized with the challenged strain or in glycolipid-immunized animals challenged with highly serum-sensitive E. coli 0.14:K7. Antibody against core glycolipid protected against the hemodynamic sequelae of bacillemia, augmented intravascular clearance of serum-sensitive organisms, and abrogated the pyrogenic response to enteric bacilli, but did not enhance clearance of serum-resistant organisms. Although canine and lapine antiserum against core glycolipid passively protected mice against a heterologous challenge, opsonophagocytic and bactericidal activity was at least 100-fold less than type-specific antiserum.

1 In a double-blind placebo controlled dose-response experiment in six asthmatic patients with reversible airways obstruction the effect of i.m. salbutamol (4 mug/kg, 8 mug/kg or 12 mug/kg) was assessed by improvement in spirometry and change in pulse rate. 2 Salbutamol (8 mug/kg) resulted in a mean increase in FEV1 of 1 litre and a mean increase in pulse rate of 7 beats/minute. 3 It was concluded that salbutamol (8 mug/kg) was the optimal dose.

SummaryCox’s Orange Pippin apple trees on M.II rootstock growing in grass on a coarse sandy loam of medium moisture retention were used to study growth and crop responses to irrigation from 1958 to 1966 inclusive. Treatments A, B and C consisted of 1, 2 and 3 in† of water applied at calculated soil moisture deficits of 1, 3 and 5 in respectively. The trees in Treatment D were not irrigated.Soil moisture deficits calculated from potential evaporation over-estimated measured soil moisture deficits by as much as 20%.Shoot and trunk growth were stimulated by irrigation during the first four years, but when the trees began to bear heavy crops the effects of watering on growth diminished considerably.Heavy bearing was not delayed by the vigorous growth induced by irrigation, and at full bearing crop yields were commensurate with the growth made. In three successive years of high yields the trees under Treatments A, B and C yielded 42%, 37% and 25% more respectively than the unwatered trees.Treatment A was uneco...

The formulae normally employed in the application of the critical-frequency method of measuring upper-atmospheric ionization are examined and are shown to be appropriate in the case of ionospheric regions which are thick when measured in terms of a wave-length. The complications arising from the occurrence of ionized clouds or strata embedded in the normal regions are described and interpreted.

The case reported exhibited bilateral posterior dislocation of the hip associated with bilateral frature of the femoral shaft. It is believed to be the only such recorded case. An excellent result was obtained following closed reduction of the dislocated hips and secondary open reduction and medullary nailing of the femoral fractures.

About 200 axolotls, between 5 and 21 months old, were treated in the body wall with carcinogens or control substances, by subcutaneous or intradermal injection, or by sub-cutaneous implantation. In response to an injection of dibenzanthracene in olive oil an initial reaction appeared within 13 days. This consisted of an epidermal proliferation and a subcutaneous infiltration of macrophages. The epidermis returned to normal after several weeks, but the subcutaneous response took 6 months to disappear. The initial reaction appeared to be, at least partially, a wound healing response; its regression could not have been due to regeneration field control as it occurred in the posterior body region. Following the disappearance of the initial reaction a secondary reaction of papilloma-like outgrowths arose between 7 and 20 months after injection. Of the axolotls surviving for a sufficient length of time, outgrowths arose in 14 out of 54 animals injected with dibenz-anthracene and in 18 out of 57 sites injected with methylcholanthrene. These outgrowths had some features in common with the papillomata of mice, but none have yet progressed to carcinomata. In a group of axolotls injected in three different regions the frequency of out-growths varied according to the sites; however, this was thought to be due to differences in the difficulty of injecting the three regions. Two tumours, a sarcoma and a hepatoma, arose in the course of these experiments, 3 and 2 years respectively after carcinogen treatment. From this it is suggested tentatively that tumour induction by polycyclic hydrocarbons in the axolotl may require a long latent period and involve a low tumour incidence; however, it is possible that at least one of the tumours was not induced by the treatment.

Iron can be determined by direct dichromate titration or otber metbods after perchloric oxidation. Perchloric oxidation does not destroy all organic material and gives acceptable results. High values of P205, K20, and NH4N03 do not interfere. Average collaborative values for iron by dichromate titration are: 12% iron, found 12.08%; 2.65% organic fertilizer, found 2.58%; 2.50% iron (with 30% P2O5 ), found 2.49%; 1.0% iron (57.5% NH4- NO3), found 1.06%; 0.18% iron, found 0.19%. It is recommended that the dichromate titration method be adopted as official, first action, and that furtber study be made on methods of sample preparation

1. Posterior bone block of the ankle is productive of permanent satisfactory correction of drop-foot deformity in a high percentage of cases. 2. If possible, the operation should be performed when the patient is between ten and twenty years of age. 3. It should be done in conjunction with arthrodesis of the talonavicular, subtalar, and calcancocuboid joints. Care should be exercised to preserve the circulation of the talus. 4. Tendon transference should be done, when possible, after the principles laid down by Peabody and Crego and McCarroll. Better results are obtained when there is a balance of power between dorsiflexors and plantar flexors of the ankle. 5. We prefer an intra-articular block, placed immediately posterior to the talus, so that it will impinge on the posterior lip of the tibia. 6. This operation should be reserved for those patients who can be rendered bracefree thereby.

With the advent of solid rocket engines utilizing high-energy aluminized propellants, the need for a noneroding nozzle-throat insert material has become acute. The wall temperatures attained at the throat are above even the maximum practical operating temperature of tungsten. However, by infiltrating a porous tungsten insert with a second material, which is subject to gasification by boiling, sublimation, or decomposition, it is possible to reduce the wall temperature to a tolerable value. This paper presents an analysis of the behavior of this so-called "self-cooling" process with infiltrated porous tungsten composites. A one-dimensional, finite thickness, flat plate model is specified. As gasification of the infiltrant proceeds, the gaseous/liquid or solid infiltrant interface recedes from the surface. The transient partial differential equations describing the model consist of the continuity, momentum, and energy relations. The effect of transpiration is included. The equations are solved by a numerical finite-difference solution that was programed for the IBM 7094. Typical results of the computer program are presented for a number of organic and inorganic infiltrants at typical high-pressure solid rocket nozzle-throat conditions to illustrate the effects of certain variables such as porosity and permeability of the porous tungsten.

The present communication deals with radio observations made by British workers as part of the general geophysical investigation of polar regions carried out during the Second International Polar Year, 1 August, 1932, to 31 August, 1933. In the long period which has elapsed since the first International Polar Year of 1882-83, the field of geophysical inquiry has been greatly extended by the use of improved methods and instruments. Such advances have been especially notable in atmospheric physics. Among the new methods which have been developed we may count the use of radio waves for the exploration of upper-atmospheric electrification. The prosecution of such methods in recent years has supplemented in many ways the information obtainable from a study of terrestrial magnetism and the aurora. The development of radio methods of ionospheric exploration has proceeded in England during the last ten years under the auspices of the Radio Research Board of the Department of Scientific and Industrial Research. On the scientific side the work has been directed to the elucidation of the structure of the ionosphere, its variation with time, and the correlation of such variations with other geophysical phenomena. Quite independently of any participation in the work of the International Polar Year, the results of work in England had, for reasons which will be stated later, suggested the need for carrying out similar observations in high latitudes, and Sir George Simpson, F.R.S., a member of the Board, had pointed out the special suitability of Northern Norway for such work. The proposals for an expedition were, however, held in abeyance because of the great advantages which were seen likely to accrue from merging such work in the international effort of the Second Polar Year.

Single intraperitoneal injections of dimethylnitrosamine (DMN) in concentrations of up to 16 mg/g body weight, failed to have any lethal effect in newts. This treatment also failed to induce tumours in newts maintained for one year after injection. Six or 7 injections of 16 mg/g body weight of DMN, administered over a period of 3-4 weeks, gave rise to a short-term lethal effect due to liver necrosis and in the long term to liver tumours. The tumours induced were of similar type to nitrosamineinduced tumours in rats, one being an anaplastic liver tumour and the other nodular hepatic cell tumours. Attempts to maintain the tumours by grafting failed, probably due to homograft rejection. ImagesFig. 9Fig. 1Fig. 2Fig. 3Fig. 4Fig. 5Fig. 6Fig. 7Fig. 8

The following are the authors' indications for the treatment of fractures of the hip in children, based on observations in this group of cases and on theoretical considerations: Type I: Transepiphyseal fractures: A. Without dislocation of femoral head: gentle closed manipulation and insertion of two or three parallel Knowles pins. The capsule of the hip joint should not be opened. B. With dislocation of femoral head: open reduction, internal fixation with two or three Knowles pins, and prolonged non-weight-bearing. Type II: Transcervical: gentle closed manipulative reduction and insertion of two or three Knowles pins. The capsule of the hip joint should not be opened. Type III: Cervicotrochanteric: A. If fragments are separated: gentle closed manipulative reduction and insertion of two or three Knowles pins. B. If fragments are not separated: a Hoke-Martin traction cast, or a Whitman abduction cast. Type IV: Intertrochanteric: gentle closed manipulative reduction and application of a Hoke-Martin tractions cast.

Fra i Leptodactylidi Australiani,Cyclorana alboguttatus ha 2n=26 come le forme piu generalizzate della famiglia, mentre alcune specie diLimnodynastes hanno 2n=22; specie di altri 5 generi hanno 2n=24. Fra questi ultimi, il problematicoRheobatrachus, completamente acquatico, possiede alcuni microcromosomi come i membri piu primitivi dell'ordine.

On a examine le metabolism de la (C14)-DMN par des coupes de foie de truite, de poisson rouge et de trois especes d'amphibiens, ainsi que l'excretion du cancerogene apres injection par voie intraperitoneale chez le triton et le poisson rouge. La relation entre le metabolisme et l'activite toxique et/ou cancerogene est discutee.

Now that measurements of upper-atmospheric ionisation can be made, using methods of radio exploration, it is of interest to see whether abnormal values of ionisation density are associated with periods of magnetic activity. We have conducted such an inquiry using the measurements of ionisation density in Region F2 of the ionosphere made at the Radio Research Station, Slough, together with the daily magnetic character figures from the Abinger Observatory supplied to us by the Astronomer Royal.

X-Ray Inhibition of Urethan-Stimulated Proliferation of Lung Cells of the Mouse as Estimated by Incorporation of Tritiated Thymidine