Volume 11, Issue 1, 2011 January-March

Volume 11, No 1 Pages:
2011 January-March Articles: 10

Editorial: It’s a natural world we are living in

Lady Gaga sings in her new hit single, Born This Way, “No matter gay, straight or bi, lesbian, transgendered life. I am on the right track ... I was born to survive.” Is not it gross, perverse, and irreverent? Do not, I repeat, do not sing this song if you happen to be in Malaysia. You could straight away be fined $16,000, with a bonus of public detestation. But that would be a blessing compared to the consequences in Nazis’ Death Camps in 1940s—you would be exterminated there.

Some generalized classes of double sampling regression type estimators using auxiliary information

In the present study, a double sampling regression type estimator representing a class of estimators is proposed. The bias and mean square error (MSE) of the proposed estimator is obtained. A more generalized class of double sampling regression type estimator utilizing the auxiliary information available at first phase in the form of mean and variance of the auxiliary variable is also proposed. The bias and MSE of the proposed class were obtained for this class. The concluding remarks show that the proposed classes of estimators are better than that of double sampling estimator based on earlier proposition. An empirical study is included for illustration.

On conformally flat weakly Ricci symmetric spacetimes

Tamassy and Binh introduced weakly symmetric Riemannian manifolds. The properties of weakly symmetric and weakly Ricci symmetric Riemannian manifolds are studied by some authors. In this paper, the conformally flat weakly Ricci symmetric manifolds is considered. In this case the Ricci tensor of Riemannian manifold is a quadratic Killing tensor, and some properties of this manifold are obtained. In conclusion, it is found that the energy momentum tensor of this space in a perfect fluid is a quasi-Einstein tensor and also a Codazzi tensor.

Growth and yield of maize under different agroforestry systems exposed to varying cultural treatments in Mizoram, India

The growth and yield of maize under three multipurpose trees (Alnus nepalensis, Gmelina arborea and Melia azedarach) subjected to application of varying intensities of different mulches was evaluated during a 3-year period (2004-2006). Maize performed considerably well under Alnus nepslensis than under other trees and sole crop. Among the mulches, subabul leaf mulch brought increased yield (10 to 36%) in maize compared to sole crop and this increase was directly proportional to dose of mulch.

Whole-rock geochemistry of augen gneiss from southeast of Dumka, Jharkhand, India

The Chhotanagpur Granite Gneiss Complex (CGGC) exhibits various geological signatures that attract many geologist and researchers for detail investigation. The present paper focused on the petrography and geochemistry of augen gneiss exposed in the southeast of Dumka, Jharkhand. As in other areas of the CGGC, augen gneiss was the main rock exposure. They were coarse-grained and light colored rocks exhibiting well gneissic characteristics. The rock was mainly composed of quartz, feldspar, hornblende, pyroxene, biotite, garnet and other opaque minerals. It was also rich in alumina and potash contents. There was also a pronounced negative Eu anomaly which suggested that both K-feldspar and plagioclase were not removed in the differentiation sequence. As the whole CGGC experienced different orogenic activities, the studied rocks also showed various deformation effects. The augen gneiss was found to be originated from granite to granodioritic igneous parentage of calc-alkaline composition in the tectonic setting within plate granite.

Physico-chemical and bacteriological investigations of tuikhur water, Saiha town, Mizoram, India

The main source of potable water in the township of Saiha is through the supply maintained by the Public Health Engineering (PHE) Department, Govt. of Mizoram. This supply is done without any proper treatment and is more or less limited especially during the non-monsoon seasons. For domestic use, the people have to depend on alternate resource systems viz. tuikhur (i.e. water seepages accumulated in artificially fabricated small pits), hand pumps and rainwater harvesting (on local level into large tanks). The water samples from different tuikhur were analyzed in the year 2007 (post monsoon) for various physico-chemical parameters such as pH, electrical conductivity (EC), total dissolved solid (TDS), turbidity, phenolphthalein alkalinity, total alkalinity, total hardness, total chloride, iron and fluoride and total coliform (MPN) for bacteriological characteristics in order to obtain the current status of potable water quality in the city. The results are suggestive of the fact that the quality of tuikhur water used for domestic purposes is by and large within the acceptable limit.

Male-male sexual behaviour in adult captive stump-tailed macaque, Macaca arctoides

The present study represents the unique features of male homosexuality in forms and context, and determines whether this behaviour is sexually motivated or sociosexual in function in captive stump-tailed monkeys, Macaca arctoides. Ten incidents of homosexual encounters between α- and β-male were observed. No reciprocal mounting was observed. Every episode of homosexual encounters was initiated immediately after the heterosexual encounter between the β-male and receptive females. The main copulatory event was anal intromission followed by ejaculation outside the mountee’s body and eating of semen by both the actors. The average number of pelvic thrust was 20. Duration of pelvic thrust and copulation were 12.3 and 54.7 sec, respectively. The α-male never copulated with any of the estrous female and there was no homosexual encounter observed between α-male and γ-male, except for brief mounts. Three lines of evidences indicated that the homosexual encounters between α- and β-male were sexual behaviour, not sociosexual ones. Firstly, mountings were observed only during the mating season. Secondly, these unique mountings did not serve any sociosexual roles and did not mimic generalized pattern of social affiliation. Finally the form of homosexual encounters was same as that of heterosexual encounters. More females in the population and occurrence of male-male homosexual encounter only during the mating season did not support the concept of intraspecific sexual differences in homosexuality.

Geochemical study of upper Bhuban sandstone in Muthi, Mizoram, India

Sandstones from the Upper Bhuban formation were measured for major oxides by X- Ray Fluorescence Spectrometry (XRF) in order to investigate palaeo-weathering, geochemical classification, and tectonic setting of the basin. The Muthi sandstone was found to have moderate to high content of SiO2 ranging from 64.54 to 76.66 wt% with an average value of 71.73 wt%. The Al2O3% content was high ranging between 10.78 to 18.19 wt% and 14.93 wt% (average). The high value of Al2O3 could be due to alteration of K-feldspar. Geochemically, the sandstone could be classified as arkose, litharenite and wacke. The sandstones were depleted in CaO (0.57) and enriched in Al2O3, Fe2O3 and Na2O. The value of chemical index alteration (CIA) in the Muthi sandstone was high 72.25 to 85.46 an average value of 79.45 indicating high intensity of chemical weathering in the source areas. The average CIA value (79.45) was above than that (50) of the upper continental crust. The geochemical parameters suggest an active continental margin for the upper Bhuban sandstones.

Digit sums of whole numbers – an analysis

Every morning on my way to office, I had to drive through the whole Aizawl city from Mission Veng to Chaltlang. I could not help looking at the registration numbers of cars in front or of those parked on the roadsides, such as, for example, MZ 01 D 2143, MZ 01 E 8379, MZ 01 F 5617, etc. All car numbers are four digit whole numbers. As a man of mathematics, I often add up the digits in my mind, noting the various sums of the digit numbers viz. 10, 27, 19 (for the above 3 car numbers). A thought came to me that the lowest possible sum for a 4-digit number would be 1 corresponding to which all possible registration numbers that can be allotted are 4 (four), viz. 0001, 0010, 0100 and 1000. It is also clear that for a given alphabet, all possible car registration numbers that can be allotted would be 9999 altogether, viz. MZ 01 F 0001 ... F 9999. The next car after F 9999 will have to be allotted G 0001 and so on.