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This chapter is a review of published research papers, books, book chapters, unpublished scientific reports prepared by research organisations, and expert talk about heavy metal pollution. This chapter also summarises the research studies conducted in Coimbatore and a summary of the studies says that very tiny information is available on heavy metals in soil, water, and air components. Till now heavy metals in plants, plant products, animals, animal products, bioaccumulation in humans, and its impacts are not accounted in this region. Further, these chapters identify the research gaps, and research interventions are required to assess the heavy metals contaminations in different ecosystems. It also highlights the need for long-term monitoring of heavy metals in the ground, surface water, food materials, agricultural products produced in the contaminated regions. The chapter concludes with a need for study on human health impacts, restoration, and remediation measures required in Coimbatore regions.

The lichen species Alyxoria culmigena (Lib.) Ertz collected from the Andaman and Nicobar Islands, is reported as a new record to India. A detailed description and figures of new record along with distribution map and key to all known Alyxoria species in India are provided.

A lichen species Syncesia farinacea (Fée) Tehler collected from the Nilgiri hills of Tamil Nadu is reported as new to India. A detailed description and figures along with additional information about its pycnidia, oil globules in young ascomata and rare isidia like structures not mentioned in earlier reports for this species are also provided.

We analyze the structure and composition of old-growth wet evergreen forest of Nelliampathy hills, the chain of hills lying immedi- ately south of Palghat Gap, in the southern Western Ghats of India. We sampled 30 plots of 0.1 ha each (50 m × 20 m) at six locations enumerat- ing all plants ≥ 10 cm girth at breast height. We pooled the data and computed various structural parameters. There were 152 species of 120 genera and 51 families of the study area. Of these, 118 (77%) were trees, 24 were climbers (16%) and 10 were shrubs (7%). Species richness var- ied from 58−99 per 0.5 ha sample and Shannon indices of diversity ranged from 4.4 to 5.2. Fifty-nine per cent (89 species) of the species were Indian Sub-continent elements and 34% (51 species) are endemic to the Western Ghats. Fifteen species are listed in various threat categories. Aglaia and Litsea were the most species-rich genera. Numbers of fami- lies ranged from 27−43 per 0.5 ha sample. Euphorbiaceae and Lauraceae were the most species-rich families. Stand density varied from 1714 to 2244 stems·ha -1 and basal area from 53.6 to 102.1 m 2 ·ha -1 . The vegetation was dominated by 3−6 species and six dominance patterns characterized the species composition within the hill complex. The old-growth ever- green forests of Nelliampathy exist as small fragments rich in biodiver- sity and can be used as benchmarks for comparison with disturbed forests.

Elytraria acaulis (L.f.) Lindau (family Acanthaceae) is a perennial herb that is distributed in tropical Africa and Peninsular India. In India, this plant has been recorded from Northern Circar, Deccan, and Carnatic regions, on the eastern side of Peninsular India. We present here a new record from the Walayar Reserve Forest in Palakkad District, Kerala, which is the first known occurrence of this species from the western side of the peninsula. This species is added to the flora of Kerala state.

The critically endangered Berberis nilghiriensis Ahrendt, endemic to the Nilgiri hills in South India is rediscovered after 140 years, with three extant populations of ca. 25 individuals in the Nilgiri hills. Taxonomic treatment along with threat status, ecology, and economic uses are provided and urgent conservation is suggested to prevent its local extinction as the species is exposed to continued anthropogenic disturbances.

Caralluma bicolor Ramach, S. Joseph, H. A. John & C. Sofiya sp. nov. (Apocynaceae) collected from Coimbatore, Tamil Nadu in India is described and illustrated. Morphological differences between the new species and the allied species C. adscendens (Roxb.) Haw. and C. sarkariae Lavranos & Frandsen are discussed.

Clay minerals such as kaolinite, illite, nontronite and montmorillonite were complexed with methylene blue, Malachite green and piperidine and their behaviour when heated was followed by differential thermal and thermogravimetric analysis. The results indicated that organic cations adsorbed on the broken bonds being easily accessible to oxygen are oxidised exothermally between 150 and 500°. The cations adsorbed in the interlayer are oxidised in the range 500 to 800° and this corresponds to the temperature at which the (OH) water is expelled from the clay minerals.

The degree of crystallinity and particle size of Ca(OH)2 inclusions in a hydrated cement matrix influence their rate of dissolution in aggressive media such as distilled water. Durability of cement-based systems (e.g. resistance to leaching and carbonation) is generally dependent on the dissolution characteristics of the products – a process leading to increased permeability and porosity. Relevant features of nano-scale Ca(OH)2 particles are explored using thermal analysis. Different forms of Ca(OH)2 with varying degrees of crystallinity and surface area were prepared using Ca(OH)2 and CaCO3 as starting materials. They were decomposed and the hydrated CaO formed at different conditions. The nitrogen surface area values of Ca(OH)2 ranged from 3.7 to 31.1m2/g. The presence of two separate and distinct thermal decomposition events (in derivative form of thermogravimetric analysis results) was observed, depending on the degree of crystallinity. Endotherms occurred at temperatures of about 426°C and 454°C. Binary mixtures of Ca(OH)2 with substantially different degrees of crystallinity exhibited a well-defined thermal decomposition doublet. The height of each endotherm peak was dependent on the mass proportions of each mixture component. Factors, including thermodynamic considerations, affecting the character of the decomposition behaviour of Ca(OH)2 are discussed.

ASTM Types I and V Portland cements were hydrated up to 28 days in the presence of 0.3%and 0.6% sulfonated melamine formaldehyde (SMF), at a water/cement ratio of 0.35.Hydration was studied by conduction calorimetric and thermogravimetric analyses. Theamount of Ca(0 Hh produced, compressive strength and porosity l!'ere determined after 1, 3,7 and 28 days of curing. The compressive strengths of all samples increased with the age ofcuring. In the period studied the values decreased in the order: Type I cement(reference) = Type I cement + SMF> Type V cement (reference) ~ Type V cement + SMF.The superplasticizer addition retarded the development of heat in the cements, but moreseverely in Type V cements. Porosities were generally higher for samples with 100vercompressive strengths. In the presence of 0.6% SMF, the early lOll' strengths in Type Vcement mixtures could be attributed to lower degrees of hvdration. At later ages, themicrostructure rather than the degree of hydration determined the strength development.However, incorporation of 0.3%SMF in Type V cement did not affect its strength development.

Six phosphonates, comprising the three acids aminotri(methylenephosphonic acid) (ATMP), 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP) and diethylenetriaminepenta-(methylenephosphonic acid) (DTPMP) and their corresponding sodium salts Na5ATMP, Na4HEDP and Na6DTPMP, were added to Portland cement in dosages ranging from 0.03 to 0.09%, at a constant water/cement ratio of 0.35 and their conduction calorimetric behaviour was investigated up to 72 h. The induction period, the time to attain the maximum heat effect and the integral heat developed at different times were determined. All phosphonates increased the induction period, from about 3 h to greater than 72 h, with respect to the reference cement with an induction period of 2 h. The acid phosphonates were more effective retarders than their corresponding salts. At a concentration of 0.05% the induction period extended from 10.1 to 21.1 h with the acids and only from 4.1 to 16.2 h with the salts. DTPMP was the most effective retarder among all the phosphonates, a concentration of 0.05% producing an induction period of 21.1 h and an exothermic inflection at 42.4 h compared with values of 2.2 and 7.9 h, respectively, for the reference. The corresponding salt (Na6DTPMP) was the most efficient of all the salt retarders. At a concentration of 0.05%, the induction period was extended to 16.2 h and the exothermal inflection to 31.4 h. In most instances the degree of extension of the induction period increased with the dosage of retarder. Phosphonates appear to be much more efficient retarders than many other retarders used in concrete practice.

Statistical analysis was carried out between seasonal milk yield and some of the derived climatic variables at a semi-arid tropical locality in Bangalore. The study revealed that the milk yields varied from the highest (9, 3 lit/cow/day) in summer season to the lowest (8, 5 lit/cow/day) in winter season and almost the same in both the monsoon season (8, 7 and 8, 5 lit/cow/day during southwest and northeast monsoon seasons). It was envisaged that the climatic components like wind chill index had negative effect while wetness index and photo-thermal heat units had both positive (summer and winter seasons) and negative (two monsoon seasons) influences on seasonal milk yields.

The visual system of primates has two anatomical pathways: magno (M) and parvo (P). Here we report a novel technique for selectively stimulating the magnocellular pathway in man. The stimulus was a texture border between black spots and white spots displayed on a uniform gray field. This stimulus (Frame 1) was followed by Frame 2, in which all the black spots were replaced with white spots and all the white spots with black. The procedure was repeated in a continuous cycle; that is, spots reversed polarity without changing positions. At high temporal frequencies (20 Hz), subjects could not see the difference between the flickering spots, but could see a phantom contour separating the two indiscriminable regions. The difference between the spots themselves could be discriminated only at about 17 Hz. Since the M pathway can follow high flicker rates but is insensitive to the sign of the border, we suggest that the phantom border is seen exclusively by the M system. The P system, on the other hand, can report the sign of the border, but only at low flicker rates. Phantom contours provide a psychophysical scalpel for producing a temporary “lesion” in the par-vocellular pathway of intact human subjects. One could therefore repeat all of classical psychophysics and physiology using phantom contours to determine whether or not a given visual process receives an M input. Also, these stimuli might provide a simple diagnostic test for revealing the loss of M-cell function that occurs in early glaucoma.

Normal people rarely confuse the mirror image of an object with a real object so long as they realize they are looking into a mirror. We report a new neurological sign, 'mirror agnosia', following right parietal lesions in which this ability is severely compromised. We studied four right hemisphere stroke patients who had left visual field 'neglect'. i.e. they were indifferent to objects in their left visual field even though they were not blind. We then placed a vertical parasagittal mirror on each patients' right so that they could clearly see the reflection of objects placed in the (neglected) visual field. When shown a candy or pen on their left, the patients kept banging their hand into the mirror or groped behind it attempting to grab the reflection; they did not reach for the real object on the left, even though they were mentally quite lucid and knew they were looking into a mirror. Remarkably, all four patients kept complaining that the object was 'in the mirror', 'outside my reach' or 'behind the mirror'. Thus, even the patients' ability to make simple logical inferences about mirrors has been selectively warped to accommodate the strange new sensory world that they now inhabit. The finding may have implications for understanding how the brain creates representations of mirror reflections.

Flounders and cuttlefish have an impressive ability to change colouration, for camouflage and, in the case of cuttlefish, for communication. We pursue the hypothesis that these diverse patterns are created by combining a small number of distinct pattern modules. Independent component analysis (ICA) is a powerful tool for identifying independent sources of variation in linear mixtures of signals. Two versions of ICA are used, one assuming that sources have independence over time, and the other over space. These reveal the modularity of the skin colouration system, and suggest how the pattern modules are combined in specific behavioural contexts. ICA may therefore be a useful tool for studying animal camouflage and communication.

A preliminary survey of medicinal plants conducted surrounding forest region of Krishna District of Andhra Pradesh, among these abnormality of wild variegated Andrographis paniculata medicinal plant and its details are reported in this paper.

The present communication deals with medicinal uses of Andrographis paniculata Nees by the tribals in Tamilnadu. Hitherto unreported uses are presented based on the Malayli tribals of Tamilnadu.

The preparation of this book was undertaken with the aim of integrating the chemistry and application of concrete superplasticizers, in a way, it is hoped, that will be relevant to conrete engineers and technologists, and useful to researchers and students. The book is divided into 14 chapters. Each chapter contains a list of important references that should serve as a useful guide to obtain further information. The first chapter, an introduction to concrete science, is included to describe the most recent concepts so that the informatin presented in subsequent chapters can be easily followed and appreciated. (A)

A yellow square was displayed on an equiluminous grey background. When a set of black spots was superimposed on the square and moved horizontally, the yellow square appeared to move in the same direction as the spots, an effect we call motion capture.1 We now report several new experiments: (a) An achromatic low contrast square was also captured although less vividly than chromatic borders. (b) TV snow was superimposed on the yellow square. If a small oscillating spot was tracked in the vicinity of the square, the square appeared to move along with the eyes, perhaps due to misapplied reafferance signals. Even if the tracking was stopped the square sometimes continued to oscillate for a few cycles. (c) Stereoscopic movement of spots in the Z-axis caused the square to be captured in the Z-axis as well. (d) If the spots moved continuously as in a conveyor belt, the square appeared to move but not change location. If a whole row of appropriately spaced squares was used, the row appeared to move continuously.

By combining brain imaging (MEG) studies with psychophysical experiments we have shown that, very soon after amputation of an arm in humans, the sensory input from the face begins to activate the original ‘hand area’ of the cortex. Many patients with a phantom arm are unable to ‘move’ their phantom arm. We used a mirror to allow the patient to see the reflection of his normal hand superimposed on the phantom. If he now moved the real arm he not only saw the phantom moving but also experienced vivid kinesthetic sensations in the phantom—a remarkable example of synaesthesia. Finally, we had a normal subject look at his own reflection superimposed on a Halloween mask seen through a half-silvered mirror. If he now made vigorous lip and tongue movements he felt his kinesthetic sensations ‘projected’ on the mask; and his ‘free will’ controlling the dummy's face (it is as though the subject regards it as highly unlikely that his own lip sensations and motor commands should be so perfectly synchronised with the movements of the mask, simply by chance). If the mask was now punched in the eye, the subject registered a strong GSR (galvanic response) demonstrating that his ‘self’ had now temporarily cast off its mortal coil to inhabit the mask. In our last experiment we had a blindfolded subject repeatedly tapping and stroking the nose of an accomplice who was sitting in front of him. If the experimenter then taps and strokes the subject's nose in perfect synchrony, the subject starts experiencing an absurd lengthening of his nose (the phantom nose). This simple experiment demonstrates the single most important fact about the mechanisms of perception—that they can discern statistical regularities in the world with astonishing rapidity.

The hydration stoichiometry, products and kinetics of dicalcium silicate are summarized. Hydration takes a similar course to tricalcium silicate, but at a much slower rate. The differences and similarities between the two compounds are identified and discussed, and future research needs identified.

Alites containing different amounts of Al, Mg or Fe were hydrated up to 30 days and their kinetics of hydration and compressive strengths were determined. At the same degree of hydration Fe-alites showed greatest strength. There was evidence that the nature of C-S-H formed in different alites is not the same.

Many aspects of the action of calcium chloride in concrete are ambiguous, controversial, or incompletely understood. Examples include: (a) the restrictive definition of calcium chloride as an accelerator; (b) the lack of clarity in prescribing the dosage for practical applications; (c) the classification of calcium chloride as an antifreezing agent; (d) the misconception regarding corrosion of reinforcement in the presence of CaCl2; (e) the divergence of opinion on the mechanism of action; and (f) incomplete understanding of the changes in the intrinsic properties of cement containing calcium chloride. This paper attempts to deal with these aspects citing typical examples.

Several aspects of building materials research that should receive more attention are discussed. The behaviour of materials is related to the physical and chemical properties of the basic ingredients and these need to be characterized properly. There is an increasing need to utilize waste and by-products. Research efforts should also be directed to develop new materials with better mechanical properties. Although tests have been used to predict the performance of materials, many of them are not related to the actual conditions to which materials are exposed in natural weathering. Efforts should be made to relate the type and concentration of pollutants to their effect on materials. Monitoring of contaminants and studying their effect on health should receive more attention. Where sufficient information on materials is available, attempts should be made to develop mathematical models to bridge the gap between science and technology.

Tetracalcium alumino-ferrite in paste form, at water/solid (W/S) ratios of 0.3, 0.4, 0.5 and 1.0, and in pressed form at effective water/solid ratios of 0.13 and 0.08 has been hydrated for up to 45 days at temperatures of 23 and 80° C. Some prehydrated samples have also been subjected to autoclave treatment at 216° C. Of all the samples studied, that hydrated at a W/S=0.13 at 80° C indicated the highest ratio of cubic phase to hexagonal phase; that hydrated at a W/S=0.08 at 23° C showed the lowest. Thermograms gave evidence of the formation of hexagonal phases, although X-ray diffraction patterns did not. The specific surface area values depended on the degree of hydration and the nature of the product, autoclaved samples giving the lowest values. During the four days of hydration the specimen hydrated at 80° C expanded more than that hydrated at 23° C, but after that time the rates of expansion were reversed: that of the sample hydrated at 80° C was much lower than that of the sample hydrated at 23° C. Microstructural examination of the material formed at higher temperatures and lower water/solid ratios indicated a closely welded, continuous network of cubic phase. Such a structure yields a product of higher strength than that of a loose structure formed at higher water/solid ratios. A reasonably linear relation was found between porosity and logarithm of microhardness.

Normal Portland cement, low C[3]A cement, tricalcium silicate, and C[3]A-gypsum mixtures are hydrated in the presence of 0,0.8,1.5 and 3.0% CaC1[2] for 1,3,7,14 and 28 days and the amounts of extractable chloride determined by applying a pressure of 80000 lb (449 MPa) or by treating the pastes with excess water. At early periods of hydration both methods yielded similar values for immobilized chloride. The amount of free chloride in the pore solution increased as the dosage of initially added chloride was increased. The C[3]A-gypsum mixture immobilized much higher amounts of chloride than did the C[3]S phase. Normal Portland cement had lower amounts of free chloride than low C[3]A cement.

Tricalcium silicate characteristically exhibits the most intense reversible transition at a temperature of about 915 degrees. The intensity of this effect can be used to estimate the amount of C(3)S in mixtures and to calculate the degree of hydration of C(3)S. Low sensitivity for deltaT up to 800 degrees and higher sensitivity between 800 degrees and 1000 degrees, enable estimation of both Ca(OH)[ 2] and C(3)S. Interference effects at higher temperatures owing to decarbonation, recrystallization to beta- wollastonite, and dehydration of the calcium silicate hydrate can be overcome by heating to 1000 degrees, cooling to 800 degrees, and reheating. A determination of the degree of hydration of C(3)S obtained at different periods by DTA correlates well with that using the X-ray method.

Using a combination of anatomical and physiological techniques we have studied some of the neural connections subserving binocular vision in two species of artiodactyl ungulates (the sheep, Ovis sp., and the goat, Capra hircus). After monocular injections of tritiated proline, transsynaptic transport was observed bilaterally in layers 4 and 6 of visual cortical areas V1 and V2, but there were no sharply defined ocular dominance columns of the kind seen in cats and rhesus monkeys. In coronal sections there was a discontinuity in density of labelling between areas V1 and V2 corresponding to a point in the visuotopic map about azimuth - 15 degrees in the ipsilateral visual field. This discontinuity was most pronounced in the hemisphere ipsilateral to the injected eye. We conclude, therefore, that while the cortical representation of ipsilateral visual space can be explained by the retino-geniculo-cortical input pathway from the contralateral eye, the physiologically demonstrated cortical contribution to ipsilateral visual space from the ipsilateral eye cannot be explained in this way. This conclusion was reinforced by experiments using retrograde transport of horseradish peroxidase from the lateral geniculate nucleus (LGN) and medial interlaminar nucleus (MIN) to retinal ganglion cells in flattened whole mounts. These experiments revealed a sharp nasotemporal decussation in the ipsilateral retina, which could not thereby subserve any significant representation of the ipsilateral visual field. In contrast the contralateral nasotemporal decussation was smeared, with many labelled ganglion cells in the temporal retina which could subserve visual input from the ipsilateral hemifield. When we estimated the projection of the nasotemporal decussation line into visual space, we found that it was tilted from vertical by about 5 degrees in each eye, in a similar way to that already reported in the cat. Neurophysiological recordings from binocular neurons in area V1 with different vertical eccentricities also showed that the vertical horopter (the midsagittal reference plane for binocular vision) would be tilted in life when the cyclotorsional position of the eyes was taken into account. Thus both anatomical and physiological methods concur in the prediction that ungulates have a tilted vertical horopter like that described for two other terrestrial species, the burrowing owl and the cat. Anatomical experiments reveal other similarities between the organisation of the ungulate's visual pathways and that of the cat. For example, after tritiated proline injections in V1, we found visuotopic labelling in the calustrum, dorsal LGN, cortical area V2, and the superior col

The slump loss characteristics of concrete containing different amounts of sulphonated melamine formaldehyde (SMF) admixed with two types of polymers were investigated. The addition of 2% polymer to SMF retarded the slump loss. The setting times although retarded were found to satisfy the requirements of the ASTM standards.

A study was designed to assess the merits of polymer addition to superplasticized cement paste, mortar and concrete. Three superplasticizers - a sulfonated melamine formaldehyde, a sulfonated naphthalene formaldehyde and a commercial superplasticizer were used in combination with experimental polymers. Polymer and super-plasticizer dosages ranged from 0-15% and 0-0,3% respectively. The effect of binary admixture systems - (superplasticizer and polymer) - on the physico-mechanical properties of the cementitious systems was determined. Properties investigated included the following; slump retention, setting time, compressive strength, flexural strength, surface area, porosity and density. Compatibility of the polymers with the superplasticizer was assessed with respect to the influence of the individual admixtures on the properties of the various systems. Synergistic effects were observed for one polymer, the results of which are discussed in detail., Proc. 3rd Int. Conf on Superplasticizers and Other Chemical Admixtures in Concrete: 1989, Ottawa, Ont. Canada