Principles and practices of rice production

Bibl. : setiap bab.Indeksxix, 618 hlm. : il. ; 22 cm

Availability of phosphorus and utilization of phosphate fertilizers in some great soil groups of Hawaii

Typescript.Thesis (Ph. D.)--University of Hawaii, 1963.Bibliography: leaves [127]-138.xiv, 138 leaves ill., diagrs., tables (2 folded)The soil is a supplier of phosphorus; and. in addition, it governs phosphorus availability through complex reactions between itself and fertilizer phosphorus. Conservative phosphate fertilization of some soils has not always effectively provided phosphorus for crop plants. Low efficiency of phosphorus recovery has long been an important, practical agricultural problem and has led many workers to study the problem of phosphorus immobilization. It is this immobilization which is believed largely responsible for low phosphate fertilizer recovery by plants and for low crop yields. Low recovery of added phosphorus by agronomic crops is a serious problem inmost Hawaiian soils. Experiments conducted by Ayres (1934) and by Chu and Sherman (1952) have shown that phosphorus fixation occurs very rapidly or even almost immediately in many Hawaiian soils. Fixation of phosphorus and thus its availability, can be regulated to some extent by certain management practices of soils. Heavy phosphorus applications are sometimes advocated to saturate the phosphorus fixation complex in soils with excess of phosphorus for plant utilization (Younge, 1961; Younge and Moomaw: 1960). Sometimes also the correct choice of a chemical compound to supply phosphorus may improve fertilizer efficiency. When the factors responsible for phosphorus fixation are understood more completely. a greater measure of fertilizer efficiency will be attained. Direct application of phosphate fertilizer material to the plant could be one solution to the soil fixation problem if a number of difficulties are overcome. Among these are: physiological burning of leaves and stems, poor recovery of added phosphorus, and lack of uniform distribution of the added nutrient within the plant. Some of these difficulties may be overcome by using suitable fertilizer material, controlled pH, proper concentration, and efficient means of application. It is widely believed that the influence of lime on phosphorus availability depends on the solubility and mobility of aluminum. The use of soil amendments such as applications of lime to acid soils may be useful in reducing the solubility and mobility of aluminum. It is commonly believed that phosphorus availability to plants increases as soils are limed close to pH 7.0; but this generalization may not apply in the tropics. Greene (1954) has reported that results from liming in the tropics have usually been unsatisfactory, and he concluded that the question of liming tropical soils should be reconsidered. In this study on phosphorus; one of the hypotheses proposed for testing was: when lime is applied before phosphorus, phosphorus reacts with the precipitated aluminum and forms a surface complex which rapidly equilibrates with the soil solution. And further, when lime is applied after the application of phosphorus, the phosphorus interacts with the surface and becomes covered by the precipitated aluminum. The objectives of the various experiments performed and reported in this thesis are summarized as follows: 1. to determine the influence of two isotopes; P31 and P32 ,phosphorus compounds, rates, and methods of phosphorus application on the availability of native and applied phosphorus in diverse soil systems. 2. to determine the availability of soil phosphorus ("A" value of Fried and Dean; 1952) as influenced by sources and various times of lime and phosphorus application in several Hawaiian soils. 3. to determine the influence of liming and phosphate fertilization on the intensity of phosphorus fixation by soils with diverse mineral systems, such as amorphous hydrated oxides, goethitegibbsite; kaolin (1:1clays), and montmorillonite (2:1 clays), in various tropical soils

A case of spontaneous transdiaphragmatic intercostal hernia of bowel loops and omentum with herniation of lung – A very rare entity

Herein we report a case of spontaneous transdiaphragmatic intercostal hernia of bowel loops and omentum with lung herniation in an elderly gentleman with Chronic Obstructive Pulmonary Disease (COPD). Initially he presented with severe cough followed by pain and small fluctuating swelling over the right chest wall. In-patient investigations were suggestive of hemothorax without any chest wall abnormality. Later the swelling gradually increased to a significant size for which he was further evaluated. Detailed imaging studies revealed it was a case of spontaneous intercostal hernia of bowel loops and omentum with herniation of lung. The patient is kept under regular follow up for optimization for his obstructive airway component for the required surgical repair of the parietal defect

Clusters of Galaxies and the Cosmic Web with Square Kilometre Array

International audienceThe intra-cluster and inter-galactic media that pervade the large scale structure of the Universe are known to be magnetized at sub-micro Gauss to micro Gauss levels and to contain cosmic rays. The acceleration of cosmic rays and their evolution along with that of magnetic fields in these media is still not well understood. Diffuse radio sources of synchrotron origin associated with the Intra-Cluster Medium (ICM) such as radio halos, relics and mini-halos are direct probes of the underlying mechanisms of cosmic ray acceleration. Observations with radio telescopes such as the Giant Metrewave Radio Telescope, the Very Large Array and the Westerbork Synthesis Radio Telescope have led to the discoveries of about 80 such sources and allowed detailed studies in the frequency range 0.15-1.4 GHz of a few. These studies have revealed scaling relations between the thermal and non-thermal properties of clusters and favour the role of shocks in the formation of radio relics and of turbulent re-acceleration in the formation of radio halos and mini-halos. The radio halos are known to occur in merging clusters and mini-halos are detected in about half of the cool-core clusters. Due to the limitations of current radio telescopes, low mass galaxy clusters and galaxy groups remain unexplored as they are expected to contain much weaker radio sources. Distinguishing between the primary and the secondary models of cosmic ray acceleration mechanisms requires spectral measurements over a wide range of radio frequencies and with high sensitivity. Simulations have also predicted weak diffuse radio sources associated with filaments connecting galaxy clusters. The Square Kilometre Array (SKA) is a next generation radio telescope that will operate in the frequency range of 0.05-20 GHz with unprecedented sensitivities and resolutions. The expected detection limits of SKA will reveal a few hundred to thousand new radio halos, relics and mini-halos providing the first large and comprehensive samples for their study. The wide frequency coverage along with sensitivity to extended structures will be able to constrain the cosmic ray acceleration mechanisms. The higher frequency (>5 GHz) observations will be able to use the Sunyaev-Zel'dovich effect to probe the ICM pressure in addition to tracers such as lobes of head-tail radio sources. The SKA also opens prospects to detect the `off-state' or the lowest level of radio emission from the ICM predicted by the hadronic models and the turbulent re-acceleration models