Life-cycle of the Pea Crab, Pinnotheres vicajii Chhapgar, infesting the clam, Paphia malabarica

Various crab stages commencing with the invasive stage to adult stages of male and female in the lile cycle of Pinnotheres vicajii infesting the edible clam, Paphia malabarica, occurring in the Mandovi estuary of Goa have been described. Except the adult male and female the rest of the stages have been described here for the first time in this species. Zoeae larvae liberated from the eggs carried by ovigerous females are characterized by the presence of 3 spines on the carapace. Comparison of these larvae with those of other species has been attempted. Planktonic zoea larvae in the estuary occur almost throughout the year with 2 peak periods in MayJune and December-January, coinciding with high salinity conditions of waters. Egg counts of 12 ovigerous females of different sizes show a minimum of 611 and a maximum of 3800 with an average of 1853 eggs. An attempt has been made to study the host-symbiont relationship. No signflcant damage has been noticed on the soft parts of the host and there is no marked difference in the meat weight - whole weight relationships of the infested and non-infested clams. However, a slight decrease has been noticed in the averages of meat weights of infested clams in the bigger whole weight groups

Origin of Large Dielectric Constant with Large Remnant Polarization and Evidence of Magnetoelectric Coupling in Multiferroic La modified BiFeO3-PbTiO3 Solid Solution

The presence of superlattice reflections and detailed analyses of the powder neutron and x-ray diffraction data reveal that La rich (BF$_{0.50}$-LF$_{0.50}$)$_{0.50}$-(PT)$_{0.50}$ (BF-LF-PT) has ferroelectric rhombohedral crystal structure with space group \textit{$R3c$} at ambient conditions. The temperature dependence of lattice parameters, tilt angle, calculated polarization $(P_{s})$, volume, and integrated intensity of superlattice and magnetic reflections show an anomaly around 170 K. Impedance spectroscopy, dielectric and ac conductivity measurements were performed in temperature range $473K \leq T \leq 573K$ to probe the origin of large remnant polarization and frequency dependent broad transitions with large dielectric constant near $T_c^{FE}$. Results of impedance spectroscopy measurements clearly show contributions of both grain and grain boundaries throughout the frequency range ($10^{3}$ Hz$\leq f\leq 10^{7}$ Hz). It could be concluded that the grain boundaries are more resistive and capacitive as compared to the grains, resulting in inhomogeneities in the sample causing broad frequency dependent dielectric anomalies. Enhancement in dielectric constant and remnant polarization values are possibly due to space charge polarization caused by piling of charges at the interface of grains and grain boundaries. The imaginary parts of dielectric constant ($\epsilon^{\prime\prime}$) Vs frequency data were fitted using Maxwell-Wagner model at $T_c^{FE}(\sim 523$K) and model fits very well with the data up to $10^{5}$ Hz. Magnetodielectric measurements prove that the sample starts exhibiting magnetoelectric coupling at $\sim 170$ K, which is also validated by neutron diffraction data.Comment: 20 pages, 10 figure

A growth walk model for estimating the canonical partition function of Interacting Self Avoiding Walk

We have explained in detail why the canonical partition function of Interacting Self Avoiding Walk (ISAW), is exactly equivalent to the configurational average of the weights associated with growth walks, such as the Interacting Growth Walk (IGW), if the average is taken over the entire genealogical tree of the walk. In this context, we have shown that it is not always possible to factor the the density of states out of the canonical partition function if the local growth rule is temperature-dependent. We have presented Monte Carlo results for IGWs on a diamond lattice in order to demonstrate that the actual set of IGW configurations available for study is temperature-dependent even though the weighted averages lead to the expected thermodynamic behavior of Interacting Self Avoiding Walk (ISAW).Comment: Revised version consisting of 12 pages (RevTeX manuscript, plus three .eps figure files); A few sentences in the second paragraph on Page 4 are rewritten so as to make the definition of the genealogical tree, ${\cal Z}_N$, clearer. Also, the second equality of Eq.(1) on Page 4, and its corresponding statement below have been remove

Kajian Kerentanan Airtanah terhadap Potensi Pencemaran di Kecamatan Kasihan Kabupaten Bantul

Perubahan penggunaan lahan atas konsekuensi pertambahan jumlah penduduk berpotensi meningkatkan risiko pencemaran airtanah di bawahnya oleh aktivitas antropogenik. Upaya perlindungan sumberdaya airtanah dapat dilakukan secara efektif dengan melakukan penilaian kerentanan airtanah. Penerapan metode DRASTIC modifikasi dengan menggunakan sistem informasi geografis (SIG) dilakukan untuk mengkaji kerentanan airtanah di Kecamatan Kasihan, yang dikenal sebagai salah satu daerah pinggiran kota yang mulai terpengaruh dampak perkembangan Kota Yogyakarta. Tujuan dari penelitian ini adalah untuk menilai kerentanan airtanah secara potensial dan aktual, serta menganalisis keterkaitan antara keduanya. Hasil penelitian ini diharapkan dapat bermanfaat sebagai tinjauan alternatif dalam upaya perlindungan airtanah bagi perencanaan pengembangan permukiman di masa mendatang. Hasil kerentanan airtanah potensial diklasifikasi pada empat tingkat, sangat rendah, rendah, sedang, dan tinggi. Zona potensi kerentanan tinggi tersebar pada wilayah yang merupakan bagian dari Dataran Kaki Gunungapi Merapi Muda. Zona kerentanan rendah terdapat pada wilayah yang merupakan bagian dari Perbukitan Struktural Sentolo dan wilayah peralihannya. Kerentanan airtanah aktual diklasifikasi pada empat tingkat berdasarkan pengaruh potensi risiko oleh faktor penggunaan lahan. Keterkaitan antara kerentanan airtanah potensial dan aktual menunjukkan pengaruh faktor penggunaan lahan dalam Perubahan status kerentanan potensial menjadi aktual