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Observations and estimates indicate that shallow water table encroachment affects increasingly large areas of agriculturally productive land in the central and western San Joaquin Valley. With current management techniques, the present drain and disposal facilities are inadequate to effectively handle the water volume that moves through soils and becomes a part of the shallow water system. In the presence of active plant roots, soil water is depleted in upper profile zones with the establishment of a potential gradient sufficient to effect upward capillary water movement in the presence of a shallow water table. A three-year study was done to evaluate the resource potential of shallow-perched water tables as a resource to meet crop evapotranspiration (ET) requirements.Using water-budget and chloride-trace techniques independently to measure shallow water table contributions to crop ET revealed that as much as 50 to 60 percent of crop ET could be met by the shallow water table. The amount of water contributed by the shallow water table was strongly conditioned by water table salinity and depth to the shallow water. Study results show the need for a total management system approach for effective utilization of the resource potential of shallow water tables in contrast to specific entities considered in isolation.

Results are presented of a two-year study comparing the evapotranspiration (ET), yields and the microclimate under drip and furrow irrigated processing tomatoes. Results from a water conservation standpoint were not encouraging with approximately equal values of evapotranspiration found for the two methods of irrigation. This was true in replicated field-plot studies as well as the lysimeter studies. The latter studies indicate that although ET under furrow irrigation was considerably higher than under drip irrigation for the three days following each furrow irrigation, this advantage largely canceled by a reversal in trends thereafter. Apparently the advection of sensible heat in air and soil to the narrow wet strips under the drip-irrigated canopy produces quite significant evaporation losses in spite of a nearly zerio under-canopy net radiation.Yield of ripe fruit in the drip irrigated lysimeter exceeded yields in the furrow lysimeter by 9% and 16% respectively in 1979 and 1980. In the replicated field-plot study yields in 1979 were not significantly different between treatments. In 1980 yield from a plastic mulched drip irrigated treatment was significantly different from the regular drip and furrow irrigated treatment. Yields for the three treatments were respectively 83.8, 66.2 and 58.6 tons/ha.

Expression of the hapten fucosyl-N-acetyllactosamine was correlated with ultrastructural development in human granulocyte precursors using the monoclonal antibody FMC 10 with immunogold techniques. The antigen was detectable from the myeloblast/early neutrophilic promyelocyte stage onwards and was associated with striking development of the rough endoplasmic reticular system. In addition, low levels of labelling were seen on monocytes, eosinophils and some basophil precursors. Contraction and alignment of the cisternae of the rough endoplasmic reticulum during the promyelocyte stage of neutrophilic differentiation gave the appearance of a plasma cell. However, on closer examination it was apparent that true plasma cells did not react with this antibody. [ABSTRACT FROM AUTHOR]

Leaf water (ψ) and solute (ψs) potential were measured in field sorghum and maize under well irrigated (I) and dryland (NI) conditions throughout a season. Despite decreases in ψ due to slow soil water depletion and to apparent increases in liquid phase plant resistance, midday leaf turgor (ψp) in the NI sorghum was maintained at similar levels as in the I treatment throughout the season due to concomitant decreases in ψs. Osmotic adjustment was also observed in maize, although ψp was significantly lower in the NI treatment as compared to I during the final stages of grain filling. A seasonal shift in the ψ vs. relative water content relation of NI sorghum leaves was observed, more water being retained by the older leaf at any particular ψ. The major factor for turgor maintenance was a net increase in solutes per unit of tissue. The role played by increases in the proportion of tissue volume occupied by cell wall was also evaluated. No stomatal closure due to water stress was found in NI sorghum even though leaf ψ reached -20 bars late in the season. Under similar conditions, stomata closed at - 14 to - 16 bars in younger plants where water stress was made to develop much faster. [ABSTRACT FROM AUTHOR]

SUMMARY A case report of cryptogenic organizing pneumonia (COP); also known as bronchiolitis obliterans organizing pneumonia (BOOP) is presented. The histopathologic findings of COP are well documented in the literature and typically consist of organizing pneumonia of uniform appearance. This case report describes, in addition to the classic findings, more acute exudative inflammation not usually associated with this condition. Variation in the evolution of the pneumonic process is one of the reasons for reporting this case. The promotion of awareness of this treatable condition is the other reason for reporting this case. When multifocal areas of consolidation are demonstrated radiologically, particularly when peripheral and basal, and in the correct clinical setting, the possibility of COP should be entertained. This condition responds dramatically to steroid therapy, and has a good prognosis. [ABSTRACT FROM AUTHOR]

SUMMARY A relatively inexpensive, technically simple method has been described for the post-mortem fixation and inflation of lungs, followed by radiography for radiologic-pathologic correlation. The major innovation in the method consists of the use of the low kV technique, with equipment already in routine use in many histopathology departments. The technique improves the diagnostic yield from routine autopsies, and provides correlative pathologic and radiologic specimens for both under- and post-graduate teaching. Permanent preservation of the lungs permits retrospective study, both from a radiological and a pathological aspect. [ABSTRACT FROM AUTHOR]

SUMMARY Variant pulmonary Assuring has been demonstrated by a routine method for fixation, air-inflation and radiography of lung specimens obtained at necropsy. While their incidence does not vary significantly from other series briefly reviewed, it is apparent that there is little emphasis in the radiological literature or teaching of these common variants, or of their practical significance in the assessment of lung disease. Correlation of the patterns found after death with pre-mortem films indicates that the relatively common superior accessory fissure, separating the apical segment of the lower lobe from the basal segments, can be most readily identified while variant lesser (transverse or lingular) fissures, and inferior accessory fissures, separating the medial basal segments of a lower lobe from the other basal segments, are less likely to be visualized. Heightened awareness of the incidence of these fissures should permit increased recognition, and thus avoid misinterpretation of the roentgen findings in pulmonary disease. [ABSTRACT FROM AUTHOR]

SUMMARY The radiological findings are described in 12 cases of malignant pleural mesothelioma diagnosed over a three-year period at the Sir Charles Gairdner Hospital in Western Australia. At presentation all showed a unilateral pleural effusion ranging from small to massive in size, with a right: left ratio of 2:1; in 8 cases a massive effusion developed at some time in the course of the disease. Pulmonary embolism was initially suspected in two cases and both underwent lower limb venography, emphasizing the similarities in presentation, with chest pain, dyspnoea and a serosanguineous pleural effusion. The sex and age distribution corresponds to that seen in series from other countries, and the radiological findings also closely conform to those reported elsewhere. Pleural nodules were evident in 9 cases, although only in one at presentation, and hilar enlargement was seen in only 4 cases. Soft tissue invasion by neoplasm was uncommonly seen on the x-rays, and rib erosion was not observed in any patient. Other radiological evidence of previous asbestos exposure or other pneumoconiosis was also uncommon and was noted in three cases. An unusual presentation of a malignant pleural mesothelioma in a 27-year-old woman with environmental childhood exposure to asbestos is described in detail, and illustrates the importance of considering mesothelioma in the differential diagnosis of any pleural effusion. [ABSTRACT FROM AUTHOR]

SUMMARY A case of pulmonary silicosis with hilar 'eggshell' calcification and calcified pulmonary nodules together with lesions of progressive massive fibrosis, is reported because of the additional and rare complication of radiologically visible silicotic involvement of the liver and spleen. The mechanism of the extrapulmonary spread of silica particles is uncertain; both haematogenous spread to the spleen, and retrograde lymphatic spread to the liver, or a combination of the two are possible. The possible role of tuberculous infection in the development of the lesions of progressive massive fibrosis and in the calcification of silicotic nodules is considered, but is thought to have been reasonably excluded in this case. The radiological and histological similarity of the lesions in both lung and extrapulmonary sites, is emphasized, and in particular, the criteria for 'egg-shell' calcification (Jacobson et al 1967) are fulfilled. [ABSTRACT FROM AUTHOR]

Experimental data and theoretical calculations of water retention by osmotic swelling of colloidal homoionic Na- and Ca-montmorillonites, vermiculites, and kaolinites were carried out at several levels of electrolyte concentration, in order to evaluate their respective contributions to the physical response of a soil system to changes in its chemical environment. Similar experiments were conducted for mixed-ion Na-Ca-montmorillonite systems to establish whether a threshold value exists for cation proportions in the exchange positions, at which the physical properties of the system show a sudden change. The results are projected as relationships between the chemical treatment and moisture contents at three equilibrium pressures. Theoretical calculations, based on the diffuse double-layer model, predict that montmorillonite systems with a certain form of cation saturation and salt content should have greater swelling pressure or higher capability for water retention than vermiculites, which have greater values than kaolinites under similar chemical conditions. This was confirmed by the experimental data, although measured values were consistently higher than those predicted by theory. The studies on mixed-ion montmorillonites show that mutual existence of the two cation species in the clay-water system produces a nearlinear relationship between exchangeable Na percentage and the moisture retention at a particular equilibrium pressure. [ABSTRACT FROM AUTHOR]

The replacement of lead (Pb)-bearing solders used in the electronic industry with Pb-free solders will become a reality in the near future. Several promising Pb-free solders have recently been identified, including Sn--0.7Cu, Sn--3.5Ag, Sn--3.8Ag--0.7Cu, and Sn--3.5Ag--4.8Bi (in wt.% with slight variations in composition). These are all Sn-rich solders with melting temperatures between 210°C and 227°C, and are recommended for various soldering applications, including surface mount technology (SMT), plated-through-hole (PTH), ball grid array (BGA), flip-chip bumping, and others. Although a considerable amount of information on Pb-free solders has been published in the last few years, the database on these new materials is still at an infant stage compared with that for Pb-containing solders. This paper addresses several aspects of the current fundamental materials understanding associated with Pb-free solders and various issues regarding their imminent use in electronic interconnect applications, including microstructure-processing property relations, mechanical properties, interfacial reactions, and the thermal-fatigue life and failure mechanisms of Pb-free solder joints. [ABSTRACT FROM AUTHOR]

Many mammalian retroviruses express their protease and polymerase by ribosomal frameshifting. It was originally proposed that a specialized shifty tRNA promotes the frameshift event. We previously observed that phenylalanine tRNA(Phe) lacking the highly modified wybutoxosine (Y) base on the 3' side of its anticodon stimulated frameshifting, demonstrating that this tRNA is shifty. We now report the shifty tRNA(Phe) contains 1-methylguanosine (m(1)G) in place of Y and that the m(1)G form from rabbit reticulocytes stimulates frameshifting more efficiently than its m(1)G-containing counterpart from mouse neuroblastoma cells. The latter tRNA contains unmodified C and G nucleosides at positions 32 and 34, respectively, while the former tRNA contains the analogous 2'-O-methylated nucleosides at these positions. The data suggest that not only does the loss of a highly modified base from the 3' side of the anticodon render tRNA(Phe) shifty, but the modification status of the entire anticodon loop contributes to the degree of shiftiness. Possible biological consequences of these findings are discussed., (Copyright 2001 Academic Press.)