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Mostly used material is concrete which has versatile quality for construction works. Fibrous concrete have significant factor that improve the scale and value to concrete for humid environments with significant role. Day by day abundant demand and use of concrete is increasing. It is considered as a 2ndlargest building material due to the major productivity. By the use of fibrous concrete, some bonding and environmental issues have been addressed. Keeping in this view, an experimental based study is conducted to evaluate the strength of fiber reinforced concrete at different percentages 0%, 0.5%, 1.0%, 1.5% and 2.0%. All percentages are added by the weight of concrete with all fibers. In this connection, one hundred and fifty-three cylinders of five mixes are prepared. Workability checked of fresh concrete during the pouring of concrete cylinders. Poured cylinders’ samples are left for different curing ages at 7 and 28 days. One hundred and two cylinders for compression at 7 and 28days but fifty-one cylinders for split tensile test at 28days with all fibers i.e. glass fiber, steel fiber, coconut fiber and polypropylene fiber. After curing, compression and split tensile tests are performed to check the strength of hardened concrete. Workability of five mixes lies between 40-90mm.Fibrous concrete is suitable for humid environment where high strength and voids less concrete are required. Addition of fibers in concrete may improves the strength parameters as well as to increase the bonding and tensile properties of concrete. It reduces the quantity of water to be used in concrete. Also the use of different types of fibers has been proved to be economical and is considered as environmental friendly construction material.

Self healing concrete are the effective methods for solving concrete deterioration and improving durability. Keeping in this view, an experimental study is conducted to evaluate the strength and healing performance of concrete made with 4% fiber for all mixes and Effective Microorganism-1 (Expounded Cracks Healing Agent) of different percentages 0%, 2%, 4% and 6%, 8% and 10%. In this connection, 108 cylinders & 54 cubes of six mixes are prepared. Workability of six mixes lies between 1mm - 38mm which is increasing by the increase of EM-1.The workability of fresh concrete using W/C ratio 0.4 is evaluated. After performing slump test, mix the all ingredients of concrete and cast the cylinders and cubes. Poured cylindrical and cubical specimens are left for different curing ages at 7, 14 and 28 days. After curing, splitting tensile strength test is performed on cylindrical specimens only and compressive strength on hardened concrete cylinders and cubes are tested and then checked the air content ratio of all six mixes which is within the acceptable ranges. After testing the cubes and cylinders are again kept in water for curing to check rate of healing and then checked the microstructure by SEM images. Cracks are small due to the use of fiber addition. By the use of EM-1, cracks can be healed. Maximum healing of crack width is between 0.04 mm to 0.07 mm if cracks width exceeds from 0.20 then it is difficult to restore. Results concluded that microorganism based self healing concrete is suitable at 6% addition in concrete which is suitable for humid environment and hydraulic structures where high strength and voids less concretes are required. Chopped strand mat can be used where concrete can be used without reinforcement.

The low affinity neurotrophin receptor (p75NTR) is implicated in promoting oligodendrocytic death after nerve growth factor (NGF) stimulation but NGF and neurotrophin-3 (NT-3) can also potentiate oligodendrocytic survival. We show regional variability in p75NTRexpression within the central nervous system of the postnatal rat; expression is readily detectable by immunohistochemistry upon a subset of CNPase-positive oligodendroglia in optic nerve but not within the cerebrum. Nevertheless, oligodendroglia isolated from the cerebrum and cultured for 16 hours express p75NTRas well as the trkC but not the TrkA gene. Viability was not, however, influenced by exposure to either NGF or NT-3. Cells overexpressing p75NTRremained unresponsive to NGF but exhibited potentiated survival with NT-3, correlating with the differential expression profile of their high affinity receptors.

Motor neurons are lost during embryonic development, but it remains controversial whether motor neuron cell death occurs during postnatal life. In this study we investigated the effect of postnatal maturation on the number of intact spinal motor neurons in the rat using retrograde labelling with model‐based counting, and an unbiased stereological counting technique. To determine the number of motor neurons innervating a specific forelimb muscle in rats of different postnatal ages FluoroGold was injected into the flexor carpi radialis. Before postnatal day 21 there were higher numbers of retrogradely labelled motor neurons than in adult rats, suggesting a ‘loss’ with postnatal maturation. This loss may be attributed to tracer diffusion to adjacent muscles and to the permeability of the muscle spindle capsule in younger animals. To obtain an unbiased estimate of the number of motor neurons in the C7 and C8 segments of the postnatal rat cervical spinal cord the fractionator/optical disector counting technique was used. This method did not show a loss of spinal motor neurons between birth and adulthood. The main conclusion from this study is that there is no loss of spinal motor neurons during postnatal maturation.

We determined if fatty acids can regulate the murine Cyp7a1 and human CYP7A1 gene promoters via peroxisome proliferator-activated receptor alpha (PPARalpha)/9-cis-retinoic acid receptor alpha (RXRalpha). In transfected cells, the murine Cyp7a1 gene promoter displayed markedly lower basal activity, but greater sensitivity to fatty acid- or WY 14,643-activated PPARalpha/RXRalpha when compared with the human CYP7A1 gene promoter. PPARalpha/RXRalpha can bind to a site (Site II) located within the region at nucleotides -158 to -132 of both promoters. Mutagenesis of the human CYP7A1 Site II element abolished the response to activated PPARalpha/RXRalpha. The murine Cyp7a1 gene promoter contains an additional PPARalpha/RXRalpha-binding site (Site I) located within nucleotides -72 to -57. Replacement of a single residue in human CYP7A1 Site I with that found in the murine Cyp7a1 Site I sequence enabled PPARalpha/RXRalpha binding, and this mutation resulted in reduced basal activity, but substantially improved the response to activated PPARalpha/RXRalpha in transfected cells. We conclude that fatty acids can regulate the cyp7a gene promoter via PPARalpha/RXRalpha. The differential response of the murine Cyp7a1 and human CYP7A1 gene promoters to PPARalpha activators is attributable to the additional PPARalpha/RXRalpha-binding site in the murine Cyp7a1 gene promoter.

Both epidural and paravertebral blocks are effective in controlling post-thoracotomy pain, but comparison of preoperative and balanced techniques, measuring pulmonary function and stress responses, has not been undertaken previously. We studied 100 adult patients, premedicated with morphine and diclofenac, allocated randomly to receive thoracic epidural bupivacaine or thoracic paravertebral bupivacaine as preoperative bolus doses followed by continuous infusions. All patients also received diclofenac and patient-controlled morphine. Significantly lower visual analogue pain scores at rest and on coughing were found in the paravertebral group and patient-controlled morphine requirements were less. Pulmonary function was significantly better preserved in the paravertebral group who had higher oxygen saturations and less postoperative respiratory morbidity. There was a significant increase in plasma concentrations of cortisol from baseline in both the epidural and paravertebral groups and in plasma glucose concentrations in the epidural group, but no significant change from baseline in plasma glucose in the paravertebral group. Areas under the plasma concentration vs time curves for cortisol and glucose were significantly lower in the paravertebral groups. Side effects, especially nausea, vomiting and hypotension, were troublesome only in the epidural group. We conclude that with these regimens, paravertebral block was superior to epidural bupivacaine.

A combined anatomical and physiological strategy was used to investigate the organization of the corticocuneate pathway in the cat. The distribution of the corticocuneate projection was mapped by means of the anterograde horseradish peroxidase (HRP) labeling technique and correlated with the nuclear cytoarchitecture in Nissl and Golgi material, the distribution of retrogradely labeled relay cells after HRP injections in the ventrobasal complex of the thalamus, and the topographic organization derived from single-and multiunit recordings in the decerebrate, unanesthetized cat. This approach provided details about the arrangement of the corticocuneate pathway that were not available from previous studies with anterograde degeneration methods.On the basis of cytoarchitectonic and connectional features, a number of subdivisions are identified in the cuneate nucleus, each of which is associated with characteristic functional properties. In agreement with previous studies, it is found that a large portion of the cuneate nucleus, the middle dorsal part (MCd), is exclusively devoted to the representation of cutaneous receptive fields on the digits. This "core" region contains more thalamic projecting neurons than any other subdivision of the cuneate nucleus. A topographic arrangement also exists in the subdivisions of the rostral cuneate and of the nuclear region ventral to MCd, although in these, receptive fields are larger and predominantly, but not exclusively, related to deep receptors and involve the arm, shoulder, and trunk.Observations on corticocuneate projections were based on injections, mainly focused on functional subdivisions of the primary somatosensory cortex (SI) as described by McKenna et al (1981). Although cortical projections are mainly to cuneate regions other than its core, a significant proportion of fibers from the region of SI where the digits are represented (particularly area 3b) do project to the MCd region of the cuneate nucleus. Similarly, nuclear areas associated with receptive fields on the arm and trunk are labeled after injection in SI arm and trunk regions, respectively. Thus, a close topographic relationship appears to exist between the somatosensory cortex and cuneate regions related to the same body representation, although nuclear regions in which receptive fields on the neck area are represented receive very sparse or no detectable cortical projections even when the injection of the tracer involves the entire sensorimotor cortex. The topographic arrangement of SI projections upon the cuneate nucleus suggests that a similar pattern exists in both structures with regard to the relative representations of distal versus proximal and deep versus cutaneous receptive fields (e.g., "core" vs. "shell" organization), and that cuneate regions preferentially related to either of these classes of receptive fields receive direct connections from the corresponding regions in SI.A comparison of the results from cats with tracer injections in areas 4 and 3b reveals that the projections from the former is denser than that arising from the latter and that their territories of termination largely overlap in the ventral portions of the cuneate nucleus. However, cortical projections to MCd may be derived from the somatosensory cortex with no contribution from area 4. The demonstration of the relative selectivity of cortical projections from different cytoarchitectonic and functional cortical areas to cuneate regions identified here provides a structural basis for the elucidation of the physiological and behavioral observations, particularly on cortical modulation of somatosensory transmission during movements.

Evidence indicates that principal features of the membrane involve structural organization of lipids in the form of a bilayer with functional proteins either bound to the bilayer surface or inserted into the bilayer and interacting within specific domains in the lipid milieux. In homeotherms, intrinsic and extrinsic factors apparently form the basis for determination of membrane lipid composition and thus membrane physicochemical properties. Moreover, many intrinsic metabolic controls, such as fatty acid desaturation and phospholipid biosynthesis, may be attenuated by change in the nature of the extrinsic or dietary influence. This review will focus on the role of dietary fat as a determinant of subcellular structural constituents to illustrate that feeding nutritionally adequate diets differing in fatty acid composition can induce physiological transitions in membrane function involving the activity of enzymes responsible for synthesis of membrane constituents, hormone‐activated functions and expression of activity in the cell nucleus.—Clandinin, M. T.; Cheema, S.; Field, C. J., Garg, M. L., Venkatraman, J., Clandinin, T. R. Dietary fat: exogenous determination of membrane structure and cell function. FASEB J.5: 2761‐2769; 1991.

Morphological and physiological features of thalamic projecting neurons in the middle region of the cuneate nucleus of cats (from obex to 4 mm below it) have been studied, using intracellular recording and iontophoresis of horseradish peroxidase. All cuneothalamic neurons in the present sample) responded to movement of hairs on wrist, paw, or digits. However, approximately 50% of the neurons could be activated by other types of stimulation (e.g., light or maintained pressure on the skin, movement of claws, etc.). No clear differences were apparent in the physiological responses correlated with the varied dendritic pattern of stained neurons. Dendritic arborizations of most cuneothalamic neurons were more extensive than assumed previously, from Golgi impregnated material. As a consequence, only a few neurons have dendrites ramifying within a restricted region--i.e., corresponding to a typical cluster of the middle cuneate nucleus. Dendrites extending in various directions and spanning a distance up to 500 microns provide cuneothalamic neurons with the ability to receive input from relatively widespread areas. Collateral branches of axons of cuneothalamic neurons were observed in 50% of the stained neurons. Most of these collaterals terminated ventrally within the cuneate nucleus. Extensive collateral arborizations were observed in the dorsal as well as the ventral cuneate. These results, together with those reported in the previous paper, suggest complex interactions of afferent inputs on cuneothalamic neurons. In particular, such neurons are likely to be influenced by convergent input from different receptor classes and, because of their axonal collaterals, probably affect the excitability of other neurons, projecting or intrinsic, in their immediate vicinity or in other nuclear regions.

The terminal arborizations of single identified cutaneous hair follicle and slowly adapting type I receptors and muscle (Ia) afferents have been studied in the cuneate nucleus of cats after intra-axonal injection of horseradish peroxidase. Penetrations were mainly at the middle and caudal levels of the nucleus--i.e., from obex to approximately 7 mm caudal to it. Following histochemical processing, the injected axons, along with their collateral branches and synaptic terminals, were visualized and examined with light and electron microscopy. Cutaneous afferents in middle cuneate (from obex to approximately 4 mm caudal to it) issued collateral branches, along the rostrocaudal axis of the nucleus, at intervals between 100 and 1,000 microns. The terminal field of each collateral's branches encompassed an area elongated largely rostrocaudally and virtually confined to the dorsal part of the middle cuneate. Although adjacent collaterals had nonoverlapping terminal arborizations, each one could give rise to separate foci of terminations. Muscle afferents differed, on the whole, from cutaneous afferents in the location and extent of collateral branching and terminal arborizations. However, because muscle fibers terminated primarily in the ventral region of the cuneate, but nevertheless exhibited sparser terminations in the dorsal part of the middle cuneate, there was some spatial overlap between zones of muscle and cutaneous projection. Synaptic boutons of cutaneous afferent fibers contained round clear vesicles, contacted dendritic profiles (sometimes more than one), and were postsynaptic to small boutons containing polymorphic vesicles. In contrast, boutons of muscle afferent fibers contacted somatic and dendritic profiles and were not postsynaptic to other boutons. The results are in general agreement with previous anatomical and electrophysiological work; however, the extent of the terminal field of single collateral branches may provide for a greater convergence of different receptor classes and of receptive fields on neurons in the middle cuneate than estimated by previous electrophysiological investigations.

In an effort to establish an optimum combination of water and nitrogen for winter wheat a field investigation was carried out on a coarse loamy sand soil during 1984–85 and 1985–86 to assess effects of irrigation regime (IR) and N application on yield, water use and N uptake. The treatments compromised all combinations of three irrigation regimes (IR) based on ratios of irrigation water to cumulative pan evaporation viz.1.2 (I-1), 0.9 (I-2) and 0.6 (I-3) and four rates of N, viz. 0, 60, 120 and 180 kg ha-1. Grain yield increased with increase in frequency of irrigation. In spite of wide differences in weather during the two years, scheduling of irrigation at IW/CPE = 1.2 gave the highest wheat yield on the coarse-textured soil. During 1984–85, the rainless year, grain yield under I-1 was 20 and 32 per cent higher than I-2 and I-3, respectively. With increasing N rate the yield and water use efficiency increased progressively upto 180 kg N under I-1 and upto 120 kg N ha-1under I-2 and I-3 regimes. During 1985–86, the wet year, grain yield response to IR was relatively low. Irrespective of IR, yield increased progressively upto 180 kg N ha-1during the wet year. Irrigation water regimes and N application also influenced leaf area index and root growth of wheat. The yield of unfertilized wheat was relatively less affected by seasonal rainfall and IR. Both N uptake and grain yield of wheat were found to increase linearly with increase in water use. Water use efficiency was highest under I-1 regime at all levels of N in the dry season of 1984–85 and under I-3 regime in the wet season of 1985–86. Increase in N uptake with increasing N rates was significantly higher under I-1 than I-2 and I-3 regimes. The N use efficiency being maximum at 60 kg N ha-1, decreased at higher N levels irrespective of IR.

Two different approaches to relate wheat yield with spectral indices derived from remotely-sensed data have been explored for the state of Punjab, India. In the study based on site-level approach yield obtained from crop-cutting sites was found to be linearly related to NIR/Red ratio derived from Landsat MSS data of corresponding sites in Ludhiana and Patiala districts of Punjab. Incorporation of agrometeorological data was also tried. Certain inherent limitations of the site-level approach led to the district-level studies which focused on the relation of district yields with corresponding average spectral indices derived from satellite sensors like Landsat MSS and lRS-LISS-i. Significant correlations were observed in all cases and the relation based on Landsat MSS/IRS LISS-I data was used for trial forecast of wheat yields for 1989-90 season. A comparison of remote-sensing based production forecast showed good agreement with the conventional estimate of Bureau of Economics and Statistics at state level although at district level, deviations were larger.

FOLLOWING axotomy most medial septal neurons in the adult rat brain have dramatically reduced numbers of choline acetyltransferase (ChAT) positive neurons. Since leukemia inhibitory factor (LIF) promotes cholinergic expression in several neuronal populations, the aim of this study was to determine if LIF would continue to support cholinergic expression in axotomized medial septal neurons. Mini-osmotic pumps were used to infuse saline or LIF into the lateral cerebral ventricle. Counts of ChAT and low-affinity nerve growth factor (p75NGFR) immunostained neurons indicated that LIF-treated animals retained ChAT expression in > 90 of axotomized neurons whereas in saline-infused animals this was < 30. Also, LIF was equally effective in maintaining p75NGFR expression levels in axotomized medial septal neurons.

Abstract: Growth responses of mesquite (Prosopis juliflora (SW) DC.) during establishment stage to planting methods and amendments were studied in a highly alkali soil (Aquic Natrustalf, ESP 94), at the experimental farm of the Central Soil Salinity Research Institute, Karnal in July, 1984. Six combinations of planting methods and amendments with and without Karnal grass (Diplachne fusca Linn. P Beauv) in the inter-row space were compared in a four times replicated field experiment in randomised block design. The mean plant height (MPH), diameter at stump height (DSH), diameter at breast height (DBH), lopped biomass 16 months past planting and total biomass attained in 2 years period were significantly less when inter-row space was planted with Karnal grass. The MPH (cm), DSH and DBH (mm) attained in 2 years period were 319, 43.4 and 15.1 in with grass as compared to 405, 53.4 and 20.3 in without grass treatments. Similarly, the total biomass attained in 2 years was about 3 times more where inter-row space was not planted with grass. Growth was better when mesquite was planted by auger hole and pit methods than in trench plantation, when the original soil was treated with gypsum at 3 kg plant–1 and then refilled. However, using trenches of dimensions 30 × 30 cm and filled with a mixture of original soil, 3 kg gypsum and 8 kg farm yard manure plant–1 appeared to be promising method for establishing mesquite plantations on highly deteriorated alkali soils. The effect of amendments on growth decreased in the order gypsum + FYM, gypsum + rice husk, gypsum, control. In two years period, 37 percent mesquite died in the trenches in which the original soil was left unchanged. Effect of treatments on nutrient concentrations and total accumulations in different segments of mesquite is discussed. Karnal grass gave 25.3 t ha–1 green forage yield in 8 cuts without amendment in a growth period of 26 months proving its great potential as a folder crop for the adverse sites. The inorganic chemical composition of the shoots, including trace elements Fe, Mn, Zn and Cu, is such as to make this species a highly promising plant for the exploitation of alkali soils. Growing Karnal grass with mesquite for a period of about 2 years reduced soil pH and EC significantly and improved organic carbon and available N contents. The grass improved water infiltration rates and moisture storage in the lower layers of the profile.

THE death of spinal motoneurones after axotomy provides a useful model for studying novel factors which prevent motoneurone loss in vivo. Peripheral nerves of newborn rats were unilaterally transected and treated with either a vehicle solution or leukaemia inhibitory factor (LIF). Compared with the vehicle controls, treatment with a gelfoam containing LIF significantly reduced motoneurone loss: from 38 to 22 after 3 days and from 55 to 38 after 7 days. The loss of motoneurones was further reduced by placing the LIF-containing gelfoam inside a silicone chamber: from 39 to 15 after 7 days, which represented a 62 rescue. Thus, LIF is a potential therapeutic agent for preventing the loss of injured or diseased motoneurones.

We investigated the function of Lhx2, a LIM homeobox gene expressed in developing B-cells, forebrain and neural retina, by analyzing embryos deficient in functional Lhx2 protein. Lhx2 mutant embryos are anophthalmic, have malformations of the cerebral cortex, and die in utero due to severe anemia. In Lhx2-/- embryos specification of the optic vesicle occurs; however, development of the eye arrests prior to formation of an optic cup. Deficient cellular proliferation in the forebrain results in hypoplasia of the neocortex and aplasia of the hippocampal anlagen. In addition to the central nervous system malformations, a cell non-autonomous defect of definitive erythropoiesis causes severe anemia in Lhx2-/- embryos. Thus Lhx2 is necessary for normal development of the eye, cerebral cortex, and efficient definitive erythropoiesis.

The retrograde transport of horseradish peroxidase (HRP) and immunocytochemistry for glutamic acid decarboxylase (GAD) have been employed to examine whether local circuit neurons (LCNs) exist in the dorsal column nuclei (DCN) and whether these neurons may be GABA-ergic. Observations focused on the dorsal part of the middle cuneate nucleus (MCd), since this region has been previously shown to contain projecting neurons whose axons terminate almost exclusively in the contralateral thalamus. After large injections of HRP in the nucleus ventralis posterolateralis and surrounding structures of the feline thalamus, the majority of neurons in MCd are labeled. These represent about 89% of the neurons in MCd as counted in 40-μm frozen sections, and about 69% as counted in plastic-embedded, 2.5-μm-thick section. Unlabeled by the same injections are some medium to largeneurons at the dorsal rim of MCd, and many characteristically small (X¯±250/μm2) neurons at the periphery of the cell clusters formed by thalamic-projecting neurons. These small neurons represent 10-12% of the neuronal population of MCd, as counted in 40-μm-thick frozen sections, and about 30%, as counted in plastic-embedded, 2.5-μm-thick sections. Neurons in this size range are also unlabeled after injection of retrograde tracer in the pretectal area, inferior and superior colliculi, inferior olivary complex, and/or spinal cord. These injections, however, result in the labeling of neurons along the dorsal rim of MCd and/or in other regions of the cuneate nucleus.In adult, colchicine-treated cats, the use of anti-GAD serum reveals a population of labeled neurons uniformly distributed throughout the DCN. In MCd, these are small (X¯=±235 μm2) neurons mainly intercalated between cell clusters, and represent about 25% of the neuronal population of this nuclear subdivision as counted in plastic-embedded, 2.5-μm-thick sections. Labeled processes densely infiltrate the cell clusters, and labeled varicosities appear to cover the soma and dendrites of unlabeled neurons. At the electron-microscopic level, most labeled profiles contain vesicles and correpond to F boutons usually involved in "axoaxonic" contacts with terminals of dorsal root afferent and presynaptic to dendrites. Other vesicle-containing, GAD-positive endings seem to correspond to the P boutons described by Ellis and Rustioni (1981) and are believed to be, at least in part, of dendritic origin. It is suggested that GAD-positive neurons are GABA-ergic LCNs and that these can mediate both pre- and postsynaptic inhibition. Their integrative role is likely to be more complex than postulated by previous electrophysiological studies.

The simulated tropospheric oxidation of diethyl ether gave yields of the products ethyl formate, acetaldehyde and ethyl acetate in broad agreement with previous studies. However the effect of variation of oxygen pressure on the relative yields of ethyl acetate and ethyl formate disagrees with the prediction of the mechanism previously proposed. It is suggested that ethyl acetate is produced by the reaction C2H5OCH(O)CH3→CH3COOC2H5+H as well as by the reaction of the 1-ethoxyethoxy radical with oxygen.

All 38 patients listed for day‐case spinal endoscopy over a 12‐month period, who had chronic severe low back pain with a radiculopathic element, were studied. The mean pain duration before treatment was 10.9 years and 50% had failed back surgery syndrome. In all patients in whom treatment was completed (n = 34), the pain‐generating nerve roots were located through symptom interaction with the patient. All had epidural scar tissue, 14 (41%) having dense adhesion. Mobilization of adhesions around the nerve root was performed so that a pocket was formed for the subsequent placement of bupivacaine, Depomedrone, and clonidine. No intra‐operative complications occurred and side effects were minimal. Follow‐up over a 12‐month period showed statistically significant reductions in pain scores and disability. Spinal endoscopy may be the diagnostic method of choice for epidural fibrosis. It has substantial therapeutic and research potential. Prospective randomized studies are required.