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Northern Corn Leaf Blight (NCLB) is a foliar disease, caused by a fungal pathogen (Setosphaeria turcica) that damages maize crop due to heavy losses in every year. A study was conducted for NCLB and identified quantitative trait loci (QTLs) in maize. Mapping population F2:3 families was developed involving two inbreds viz CM 212 (susceptible) & CM 145 (resistant).The F2:3 families mapping population was evaluated in two environments (BHU, Varanasi and Nagenahalli, Mandya) for resistance to NCLB. In the polymorphic survey about 360 pairs of simple sequence repeat (SSR) primer used between two parents (CM 212 & CM 145)and identified 54 polymorphic markers. Data was recorded for disease severity traits viz Percent Disease Index (PDI), Area Under Disease Progress Curve (AUDPC) based on PDI, Lesion Area, AUDPC based on lesion area in QTL Mapping. The QTLs were identified interestingly, on 4th chromosome viz: 4.03/4.05, 4.08/4.1, 4/4.07 and 4.08/4.1 from observed disease severity in both environments. The initially two QTLs (QTL-1 & QTL-2) detected with trait Percent Disease Index and other two (QTL 3 & QTL 4) detected with AUDPC based on PDI.

A real n by n matrix B is a P_0^+ -matrix if for each k in {1, 2, . . . , n} every k by k principal minor of B is nonnegative, and at least one k by k principal minor is positive. A digraph D is said to have P_0^+-completion if every partial P_0^+-matrix specifying D can be completed to a P_0^+ -matrix. In this paper, we study the P_0^+-completion problem, give necessary conditions for a digraph to have P_0^+-completion, and single out those digraphs of order at most four that have P_0^+-completion.

In this paper, the nonnegative $Q$-matrix completion problem is studied. A real $n\times n$ matrix is a $Q$-matrix if for $k\in \{1,\ldots, n\}$, the sum of all $k \times k$ principal minors is positive. A digraph $D$ is said to have nonnegative $Q$-completion if every partial nonnegative $Q$-matrix specifying $D$ can be completed to a nonnegative $Q$-matrix. For nonnegative $Q$-completion problem, necessary conditions and sufficient conditions for a digraph to have nonnegative $Q$-completion are obtained. Further, the digraphs of order at most four that have nonnegative $Q$-completion have been studied.

The present study compares structural and optical modifications of lead sulfide (PbS) quantum dots under swift heavy ion (SHI) irradiation. PbS quantum dots are prepared following an inexpensive chemical route using polyvinyl alcohol as the dielectric host matrix. SHI irradiation of the samples is carried out with 100 MeV Si7+ ion beam with fluences in the range from 1×1011 to 3×1013 ions cm−2 and their structural and optical properties, before and after irradiation, are compared by X-ray diffraction (XRD), photoluminescence (PL) and UV–Vis spectroscopy. The structural parameters of PbS quantum dots are studied by X-ray line profile analysis using the Williamson–Hall plot. The values of average crystallite sizes are found to vary from 8 to 18 nm. XRD studies confirmed the formation of the cubic nanocrystalline PbS. Improvement of crystalline quality for lower fluences is exhibited by an increase in the X-ray intensities of the films. The UV–Vis absorption spectra reveal blue shift relative to the bulk mat...

A protocol was developed for preservation of calli of Oryza rufipogon Griff. in liquid nitrogen (-196°C). Optimal conditions for cryoprotection, pre-freezing and post-thaw recovery of calli were identified. Cryoprotectant treatment at low temperature, pre-freezing in isopropanol bath for 1 h at -70°C, rapid thawing and proper removal of cryoprotectant were critical for post-thaw survival. Genetic fidelity of the R1 plants obtained from cryopreserved, cryoprotectant-treated and untreated calli was assessed by phenotypic and molecular characterization. Comparison of phenotypic characters with seed-derived control plants showed no significant variation in the agronomic characters, but seed physical characters showed significant reduction in all the in vitro generated plants. Molecular data generated using 26 rice simple sequence repeat markers showed 4.78-7.25% change from control. Results suggested that both callus induction and cryopreservation induced heritable variations in O. rufipogon. In addition, a combination of phenotypic and molecular characterization using an appropriate marker provided better insight into genetic fidelity of recovered plants.

With the growing understanding of the role of radon and its daughter products as major sources of radiation exposure, the importance of large number of estimation of radon concentration in various parts of the country is realized. Inhalation of radon, thoron and their decay products is the major source of the total radioactive dose received by the human population from natural radiation. The indoor radon and thoron progeny levels in Nalbari area of Assam are studied by using the LR-115 (type II) Solid State Nuclear Track Detector in Plastic Twin Chamber dosimeter. Radon and thoron progeny levels in different types of dwellings for one full calendar year are presented in this paper. For Assam Type (A.T.) houses, indoor radon progeny concentrations vary from 0.17 to 0.64 mWL with an annual geometric mean of 0.27 mWL and that for Reinforced Cement Concrete (R.C.C.) houses vary from 0.22 mWL to 0.60 mWL with the annual geometric mean of 0.37 mWL. The thoron progeny levels in A.T. houses also vary from 0.01 to of 0.05 mWL with an annual geometric mean of 0.02 mWL and that for R.C.C. houses vary from 0.02 to 0.08 mWL with the annual geometric mean of 0.04 mWL.

X-ray diffraction patterns of chemically deposited lead sulphide thin films have been recorded and X-ray line profile analysis studies have been carried out. The lattice parameter, crystallite size, average internal stress and microstrain in the film are calculated and correlated with molarities of the solutions. Both size and strain are found to contribute towards the broadening of X-ray diffraction line. The values of the crystallite size are found to be within the range from 22–33 nm and the values of strain to be within the range from 1·0 × 10−3–2·5 × 10−3.

For acyclic and unicyclic graphs we determine a necessary and sufficient condition for a graph G to be singular. Further, it is shown that this characterization can be used to construct a basis for the null-space of G.

Nanocrystalline thin films of CdS are deposited on glass substrates by chemical bath deposition technique using polyvinyl alcohol (PVA) matrix solution. Crystallite sizes of the nanocrystalline films are determined from broadening of X-ray diffraction lines and are found to vary from 5·4–10·2 nm. The band gap of the nanocrystalline material is determined from the UV spectrograph. The absorption edge is shifted towards the lower wave length side (i.e. blue shift) and are found to be within the range from 2·48–2·8 eV as grain sizes decrease from 10·2–5·4 nm. This is also supported by the spectral response curves. An increase of molarity decreases the grain size which in turn increases the band gap.

Photoconductivity of thermally evaporated ZnTe thin films was studied at different elevated temperatures. A gap type cell configuration with Al electrodes on glass substrates was used. The conductivity was found to obey two distinct conduction mechanisms within the region of applied fields. At low fields the photoconduction is ohmic and at high fields it is of Poole-Frenkel type. With increase of ambient temperatures, the Poole-Frenkel conductivity regions were found to extend to lower fields. The temperature dependence of dark conductivity also was found to be of similar nature.

The column rank of an m by n matrix A over the nonnegative reals is the dimension over the nonnegative reals of the column space of A. We compare the column rank with the factor rank of matrices over the nonnegative reals. We also characterize the linear operators which preserve the column rank of matrices over the nonnegative reals.

Solid State Nuclear Track Detectors (SSNTDs) are widely used for the determination of indoor radon and thoron levels. They are the most effective passive detectors available to obtain time integrated levels of radon, thoron and their daughters. This article gives the results of measurement and analysis of both radon and thoron in dwellings of different types in the hilly regions surrounding Guwahati, Assam made over a full year, covering all four seasons. The measurements were carried out using the passive time-integrated method by employing LR-115 (type II) detectors in plastic twin-chamber dosimeter cups. The estimated indoor radon levels varied from 101.1 to 238.5 Bq m 155.4 Bq m 3 with a mean of 3. The thoron levels were found to vary from 13.0 to 57.9 Bq m 1.

The current (I)-voltage (V) characteristics of thermally evaporated CdSe thin films having thickness in the range 850–3000 A and deposited within the substrate temperature of 303–573 K show nearly linear dependence at low voltage and afterwards a non-linear behaviour at higher voltage range. A detailed study ofI-V curves in dark and under illumination clearly reveals the mechanism as ohmic at low voltage and that of trap limited space charge limited conduction (SCLC) at higher voltage. The transition voltage (Vt) from ohmic to SCLC is found to be quite independent of ambient temperature as well as intensity of illumination. SCLC is explained on the basis of the exponential trap distribution in CdSe films. Trap depths estimated from the lnI vs 103/T plots are found to be within 0.60-0.37 eV. Using the relevant SCLC theory, the carrier concentration, n0, total trap concentration, Nt, and the ratio of free charge to trapped charge, θ, have been calculated and correlated with ambient temperature and intensity of illumination.

Radon/thoron and their progeny concentrations were measured in different types of dwellings at different locations around industrial areas, cities and rural areas of Brahmaputra Valley of Assam by using LR-115 (type-II) plastic detector. Radon levels of different dwellings were analysed with reference to the nature of building materials, ventilation patterns and the types of underlying soil. The results were discussed under the light of exposure limits set by ICRP. The average concentrations of indoor radon and thoron varied from 39.5 to 215.2 Bq m −3 and 12.9 to 37.6 Bq m −3 , respectively. The estimated inhalation dose due to radon, thoron and their daughter products in the study areas varied from 0.53 to 1.00 μSv h −1 .

The present study evaluated the water quality of Dighali Pukhuri, a freshwater pond ecosystem in Guwahati city, using Biological Water Quality Criteria (BWQC). The study determined water quality class of the sampling site taking into accounts of both Saprobic score and diversity score of aquatic insects using BWQC. Sampling was done in monsoon, post-monsoon, winter and pre-monsoon seasons during the year 2010-11 and 2011-12. Results of the study were compared with BWQC to assign different classes to the study site. The most prevalent biological water quality Class was “B” (slight pollution) which accounted for about 65.5% of the total classes present. It was followed by Class “C” (moderate pollution) which accounted for 25% of the total biological water quality classes. The Class “A” (clean) contributed only 12.5%. The prevalence percentage of different biological classes can be shown as Class “B” > Class “C” > Class “A”.

Time-dependent sporulation, conidial size and germ tube formation in Alternaria tenuissima (Kunze ex Pers.) Wiltshire on different media were studied. The results indicate that maximum number of first spore was formed on potato dextrose agar (PDA) and new leaf extract of pigeon pea followed by old leaf extract of pigeon pea and distilled water (DW). The sporulation was relatively poor on other media. The maximum number of spores in a chain were produced on PDA and albumen +0.9% sodium citrate. Only one spore was seen in DW. According to time-dependent sporulation, the media were divided into three categories: on some media the first spore was formed in 18 h, in another group it took 30–36 h and in the third group the first conidium was formed after 40 h. Four germ tubes were commonly formed on most of the media. The largest conidia were observed on potato dextrose and the smallest ones were seen on DW. Zusammenfassung Untersucht wurde die zeitabhangige Konidienbildung, die Konidiengroie sowie die Keimschlauchentwicklung in Alternaria tenuissima (Kunze ex Pers.) Wiltshire auf verschiedenen Nahrmedien. Die Ergebnisse zeigten, dass die hochste Zahl an erstgebildeten Konidien auf PDA (Kartoffel-Dextrose-Agar) und NLE (Taubenerbsen-Neublattextrakt-Agar) nachgewiesen werden konnte; auf OLE (Taubenerbsen-Altblattextrakt-Agar) und DW (destilliertes Wasser-Agar) wurden weniger Konidien gebildet. Die Konidienbildung auf anderen Nahrmedien war vergleichsweise schlecht. Konidien in Ketten wurden auf PDA und ASC (Albumin+0,9% Natiumcitrat-Agar) am starksten gebildet. Auf DW wurden nur einzelne Konidien beobachtet. Die Konidienbildung konnte in drei Zeit-Kategorien gruppiert werden: auf einigen Medien wurden die Initialkonidien innerhalb von 18 Std. gebildet, in einer zweiten Gruppe dauerte die Konidienbildung 30–36 Std. und in der dritten Nahrmediumgruppe uber 40 Std. Die Konidien keimten haufig mit vier Keimschlauchen auf fast allen Nahrmedien aus. Die groiten Konidien wurden auf PDA, die kleinsten auf DW gebildet.

Thermally evaporated ZnSe thin films deposited on glass substrates within substrate temperatures (T s)at 303 K-623 K are of polycrystalline nature having f.c.c. zincblende structure. The most preferential orientation is along [111] direction for all deposited films together with other abundant planes [220] and [311]. The lattice parameter, grain size, average internal stress, microstrain, dislocation density and degree of preferred orientation in the film are calculated and correlated with T s.

We have reanalysed the UBV light curves of Abhyankar (1962b) using the 1993 version of Wilson- Devinney computer programme with a view to derive a consistent solution in all the three passbands and to an- swer the discordant opinions on the general picture of YY CMi. Initially, a preliminary unspotted solution was ob- tained and a photometric mass ratio was derived. From the present analysis, we obtained a mass ratio of q =0 :89 which diers from the mass ratio of 0.8 derived by Giuricin & Mardirossian (1981) and 0.65 derived by Abhyankar (1962b) but agrees with the value of 0.885 derived by Niarchos et al. (1998). Finally, the light curves were mod- elled by introducing a spot on the cooler secondary com- ponent to represent the observed light curve asymme- tries. Assuming the mass of the primary component to be 1:56 m(F1V), the absolute elements of YY CMi are found to be mc =1 :39 m, Rh =2 :52 R, Rc =2 :38 R, Log Lh =1 :13 L ,L og L c =0 :86 L ,L og g h =3 :83 and Loggc =3 :83. The primary and secondary components are found to be slightly overluminous and bigger in size when compared to stars of the same mass. In the H-R diagram (log Te versus log L, ZAMS), both the components are above but near the ZAMS suggesting that both of them have left the main sequence and have come into contact. Our results essentially agree with those of Niarchos et al. (1998) based on V passband only.

The analysis of the photometric B and V light curves of the semidetached eclipsing binary V Crt, using the Wilson‐Devinney method, yielded photometric elements, including a photometric mass ratio of 0.40. Assuming the mass of the primary component to be 1.70 M⊙ (F0 V), the absolute elements of V Crt are found to be \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \usepackage[OT2,OT1]{fontenc} \newcommand\cyr{ \renewcommand\rmdefault{wncyr} \renewcommand\sfdefault{wncyss} \renewcommand\encodingdefault{OT2} \normalfont \selectfont} \DeclareTextFontCommand{\textcyr}{\cyr} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} \landscape $m_{c}=0.68\,M_{\odot }$ \end{document} , \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathr...

TheUBV light curves obtained by Duerbeck (1975) andHa (wide) and Ha (narrow) light curves obtained by Chambliss & Davan (1987) of the detached eclipsing binary VV Orionis (VV Ori) were analysed using the Wilson-Devinney method fixing the two parametersT h (25,000 K) and q(0.4172), resulting in the following absolute elements:A = 13.605 ± 0.03 LR⊙,R h = 5.03 ±0.03R ⊙, Rc = 2.43 ±0.02R ⊙,M bol,h = -5.18 ± 0.11,M bol,c = -1.54 ± 0.06,m h =10.81 + 0.42m ⊙ andm c = 4.51 ± 0.41m ⊙. The de-reddened colours obtained from applying the reddening corrections ofE(B-V) = 0m.05 andE(U-B) = O m .04, and the derived temperatures of the components, gave spectral types ofB 1.5V for the primary and 54-5V with anUV excess of 0 m ·3 for the secondary component. A comparison of the logL and logT e of the components with the observed ZAMS shows the primary component to be a little above and the secondary component to be a little below/or on the ZAMS. A comparison of the properties of the components of VV Ori and a few other detached systems with the normal stars in the logL, logR and logT e versus logm planes, indicated a need for either a readjustment of the scales of the above parameters or modifications in the theoretical models. From the position of the components on the evolutionary tracks of Pop I composition computed by Schaller et al. (1992) it is noticed that while the primary component of W Ori had slightly evolved along the main-sequence, its secondary is still unevolved. The age of VV Ori is found to be 10 ± 1 million years and it is at a distance of 368 ± 10 pc.

The fuzzy subgroups of a group which are invariant under various operator domains are studied. In particular, the classes of all inner automorphisms, automorphisms, and endomorphisms are applied on the fuzzy subgroups of a group. As a consequence, two distinct partitions of a group, which are successively coarser than the family of all conjugate classes, are discovered.

A real [Formula: see text] matrix is a [Formula: see text]-matrix if for [Formula: see text] the sum of all [Formula: see text] principal minors is positive. A digraph [Formula: see text] is said to have positive [Formula: see text]-completion if every partial positive [Formula: see text]-matrix specifying [Formula: see text] can be completed to a positive [Formula: see text]-matrix. In this paper, necessary conditions for a digraph to have positive [Formula: see text]-completion are obtained and sufficient conditions for a digraph to have positive [Formula: see text]-completion are provided. The digraphs of order at most 4 that include all loops and have positive [Formula: see text]-completion are characterized. Tournaments whose complements have positive [Formula: see text]-completion are singled out. Further, some comparisons between the [Formula: see text]-matrix and positive [Formula: see text]-matrix completion problems have been made.

Light curves of the long period RS CVn type eclipsing binary RZ Eri, obtained during the period 1976–1979 with the 1.2 m telescope of the Japal-Rangapur Observatory are analysed, using Wilson-Devinney method, by fixing the two parametersT h (7400°K) andq(0.963), resulting in the following absolute elements:A = 72.5 ± 1.4R ⊙,R h = 2.84 ± 0.12R ⊙,R c = 6.94 ± 0.20R ⊙,M bol,h = 1.35 ± 0.28,M bol ,c= 1.41 ± 0.28,m h = 1.69 ± 0.6m ⊙ andmc= 1.63 ± 0.13m ⊙. The presence of humps and dips of varying amplitudes at a few phases in the normal UBV light curves is explained as due to residual distortion wave. The derived (B-V) and (U-B) colours of both the components appear to have been reddened to an extent of 0 m .20 in (B-V) and 0 m .16 in (U-B) colours. This reddening is attributed to the presence of an envelope around the system, the material of which might have come from the loss of mass experienced by the evolving cooler component. Taking into consideration the dereddened colours and temperatures of the components, spectral types ofF0 IV for the primary and G 5–8 III–IV for the secondary component were derived. The fractional radii of 0.039 and 0.096 of the two components, when compared with the radii of their critical Roche lobes of 0.378 and 0.372 suggest that these components are well within their critical sizes. From the position of the components on the. isochrones and the evolutionary tracks of stars of Pop I composition computed by Maeder & Meynet, it is concluded that the evolution of the components of RZ Eri is abnormal. This system is found to be situated at a distance of 185 pc, with an age of about 2.5 × 109 yrs.

A particular class of pairs of fuzzy subgroups of a group, where the product of the members is again a fuzzy group, is characterised and called the class of conormal pairs of fuzzy groups. Homomorphic images and pre-images of conormal pairs are studied. Lastly, it has been shown that any pair of fuzzy subgroups can be restricted to a maximal subgroup in such a way that the restricted pair becomes conormal.

Variability among 26 isolates of Sclerotium rolfsii collected from various hosts/soil samples and localities in India is reported. The isolates varied in colony morphology, mycelial growth rate, sclerotium formation, teleomorph production and sclerotial size and color. Out of 26 isolates, only 4 produced the teleomorph stage on Cyperus rotundus rhizome meal agar medium. Mycelial incompatibility among the isolates was also seen, and out of 325 combinations, only 29 combinations (8.9%) showed compatible reactions. Based on mycelial compatibility, 13 vegetative incompatibility groups (VCG) were identified among the isolates. HPLC analysis of the ethyl acetate fraction of culture filtrates of the isolates revealed 10-22 peaks. Six peaks were identified as gallic, oxalic, ferulic, indole-3-acetic acid (IAA), chlorogenic, and cinnamic acids. Oxalic, IAA, and cinnamic acids were present in the culture filtrates of all the isolates in varying amounts. The other three phenolic acids were not detected in some of the isolates. A comparative HPLC analysis of sclerotial exudate, sclerotia, mycelia, and culture filtrates of two S. rolfsii isolates (leaf spot- and collar rot-causing) producing different symptoms on their respective hosts revealed variation in the content of phenolic acids, IAA, and oxalic acid.

A real n x n matrix is a Q-matrix if for every k = 1, 2, . . . ,n the sum of all k x k principal minors is positive. A digraph D is said to have Q-completion if every partial Q-matrix specifying D can be completed to a Q-matrix. For the Q-completion problem, sufficient conditions for a digraph to have Q-completion are given, necessary conditions for a digraph to have Q-completion are provided, and those digraphs of order at most four that have Q-completion are characterized.

PbS quantum dots are prepared on glass substrates as thin films by chemical bath deposition (CBD) method. The structure of nanocrystalline PbS is characterized by X‐ray diffraction and the size of the crystallites are found to vary from 5–10 nm. The UV‐visible absorption spectra show a large blue shift that increases the band gap up to 2.89 eV on decrease of molarity. Photoluminescence (PL) study indicates the size effects where PL peaks are found around 475–538 nm. IR spectra studies are made on all the films which show the relevant functional groups in addition to PbS bonding.

Results of analysis of photoelectric observations of the RS CVn eclipsing binary WY Cancri in the standard passbands ofUBV during 1973-74, 1976-79 and inUBVRI during 1984-86 are reported. A preliminary analysis of the eclipses suggested the primary eclipse to be transit. A study of the percentage contribution of the distortion wave amplitudes in all the colours with respect to the luminosities of both components, showed the hotter component to be the source of the distortion wave. The clean (wave removed) light curves of different epochs have not merged, suggesting residual effects of spot activity. The reason for this is attributed to the presence of either (1) polar spots or (2) small spots uniformly distributed all over the surface of the hotter component. This additional variation is found to have a periodicity of about 50 years or more. The distortion waves in yellow colour are modelled according to Budding’s (1977) method. For getting the best fit of the observations and theory, it was found necessary to assume three or four spots on the surface of the hot component. Out of these four spot groups, three are found to have direct motion with migration periods of 1.01, 1.01 and 2.51 years while the fourth one has a retrograde motion with a migration period of 3.01 years. From these periods and the latitudes of the spots derived from the model a co-rotating latitude of 4ℴ is obtained. The temperatures of these spots are found to be lower than that of the photosphere by about 700ℴK to 800ℴK. Assuming the light curve of 1985-86, which is the brightest of all the observed seasons, to be least affected by the spots, the light curves of the other seasons are all brought up to the quadrature level of this season by applying suitable corrections. The merged curves in theUBVRI colours are analysed for the elements by the Wilson-Devinney method. This analysis yielded the following absolute elements: $$\begin{gathered} m_h = 0.86 \pm 0.03{\text{ }}M_ \odot \hfill \\ m_h = 0.51 \pm 0.03{\text{ }}M_ \odot \hfill \\ R_h = 0.99 \pm 0.02{\text{ }}R_ \odot \hfill \\ R_c = 0.65 \pm 0.02{\text{ }}R_ \odot \hfill \\ T_h = 5520^o K \pm 100^o K \hfill \\ T_c = 3740^o K \pm 20^o K \hfill \\ M_{h(bol)} = 4\mathop .\limits^m 96 \pm 0.10 \hfill \\ M_{c(bol)} = 7\mathop .\limits^m 58 \pm 0.15 \hfill \\ Spectral type hotter component = G5 \pm 1 \hfill \\ cooler component = K9 \pm 1 \hfill \\ \end{gathered} $$ For a mass ratio of 0.506 and with the derived fractional radii rh = 0.241 andr c = 0.157, both the components are found to be within their Roche lobes. Hence we have classified WY Cnc as a detached system. From their positions on the HR diagram it is concluded that both the components of WY Cnc belong to the main sequence.

B andV observations of the suspected variable BV 690 = NSV 04298 are reported. The star shows light variations with a period of ld.2400 and with amplitudes of 0m.27, 0m.36 and 0m.11 inV, B, andB-V respectively. The light curves show steeper rise than decline, and there is evidence for the presence of a bump in the descending branch around the phase of 0.35. From considerations of the period, spectral type, presence of the bump and high tangential velocity we conclude that BV 690 belongs to the BL Herculis class of Typen Cepheids

The light outside the eclipses of the totally eclipsing RS CVn binary SV Camelopardalis (SV Cam) is Fourier analysed and the amplitudes of the distortion waves have been derived. The distribution of the percentage contributions of these amplitudes inV, B andU colours with respect to the luminosities of the binary components indicates that the hotter component is the source of the distortion waves. These distortion waves, attributed to star spots, are modelled according to Budding (1977) and spot parameters like longitude, latitude, temperature and size are obtained. From this study it is noticed that while symmetric waves with two minima could be fitted satisfactorily, asymmetric waves with more than two minima could not be fitted well. From the longitudes of the minima of the best fitted curves, migration periods of four spot groups are determined. Assuming synchronism between rotation and orbital periods, the rotation periods of the four spot groups are derived from their migration periods. The period of rotation of one of the spot groups having direct motion is found to be 0d.5934209 while the periods of the other three spot groups having retrograde motion are 0d.5926588, 0d.592607 and 0d.5924688. As the latitudes of these spots are known from modelling parameters, the latitude having a rotation period equal to that of the orbital period (co-rotating latitude) is found to be about 30°

Medetomidine was injected by the intramuscular route at the rates of 3 and 5 microg/kg body weight into two groups of Indian elephants (Elephas maximus). Sedation was induced at 6.20 (0.81) and 5.90 (0.60) min respectively after injection. The duration of anaesthesia was 66.20 (10.4) and 134.20 (24.12) min, respectively and recovery occurred at 125.80 (25.23) and 205.89 (29.3) min. The notable signs of sedation exhibited by the elephants were protrusion of penis, complete relaxation of trunk, flaccidity of tail and drooping of the ears with a head down position. During sedation, physiological parameters recorded were bradycardia, decreased respiration and hypothermia.