On the CR transversality of holomorphic maps into hyperquadrics

Let $M_\ell$ be a smooth Levi-nondegenerate hypersurface of signature $\ell$ in $\mathbf C^n$ with $n\ge 3$, and write $H_\ell^N$ for the standard hyperquadric of the same signature in $\mathbf C^N$ with $N-n< \frac{n-1}{2}$. Let $F$ be a holomorphic map sending $M_\ell$ into $H_\ell^N$. Assume $F$ does not send a neighborhood of $M_\ell$ in $\mathbf C^n$ into $H_\ell^N$. We show that $F$ is necessarily CR transversal to $M_\ell$ at any point. Equivalently, we show that $F$ is a local CR embedding from $M_\ell$ into $H_\ell^N$.Comment: To appear in Abel Symposia, dedicated to Professor Yum-Tong Siu on the occasion of his 70th birthda

Formal and finite order equivalences

We show that two families of germs of real-analytic subsets in $C^{n}$ are formally equivalent if and only if they are equivalent of any finite order. We further apply the same technique to obtain analogous statements for equivalences of real-analytic self-maps and vector fields under conjugations. On the other hand, we provide an example of two sets of germs of smooth curves that are equivalent of any finite order but not formally equivalent

Pathological changes and local defense reaction occurring in spontaneous hepatic coccidiosis in rabbits (Oryctolagus cuniculus)

[EN] Hepatic coccidiosis occurred in 56 rabbits belonging to different ages, sexes and breeds during the years from 2002 to 2005. Clinically, the severely affected rabbits showed decreased growth rate, anorexia, debilitation, listlessness, diarrhea, icterus and rough hair coat. Postmortem examinations revealed increased dirty dull straw colored peritoneal fluid. Hepatomegaly, with presence of discrete yellowish-white nodules of 1mm to 1 cm size on the surface and throughout the parenchyma, was seen. Smears from peritoneal fluid showed rafts of mesothelial cells. Impression smears from the liver nodules revealed presence of numerous developmental stages of Eimeria stiedae corresponding with the stage of the liver lesion. These were intermixed with sheats of hepatobiliary cells and inflammatory cells and the changes were reflective of the histological changes like biliary hyperplasia, cholangitis and vacuolar changes occurring in the liver. There was increase in the thickness of basement membrane with the advanced stage of the lesion. The basement membrane was up to 1-2 µm in thickness forming loop like structures over which resided hyperplastic biliary cells containing different stages of the parasite. Some thickened basement membranes were devoid of overlying cells which had desquamated and were present in the ductal lumens suggesting that the basement might have the local defensive role in warding of the coccidial infection. The basement membrane was positive for neutral mucopolysaccharides while as the inflammatory zones and biliary epithelia along with the gametogonic stages of the coccidium reacted positively to the increased acid mucopolysaccharides qualitatively. The results showed that the occurrence of hepatic coccidiosis in female rabbits coincided with the breeding and kindling periods. Direct wet mount smears from bile aid in diagnosis of the disease. Impression smears from the liver nodules might represent the histological changes in the liver. The basement membrane thickening might have a defensive role in warding off the coccidial infection.Darzi, M.; Mir, M.; Kamil, S.; Nashiruddullah, N.; Munshi, Z. (2007). Pathological changes and local defense reaction occurring in spontaneous hepatic coccidiosis in rabbits (Oryctolagus cuniculus). World Rabbit Science. 15(1):23-28. doi:10.4995/wrs.2007.608232815

Genetic variability and correlation studies in grapes (Vitis vinifera L.) in Leh District of Jammu and Kashmir

The present investigations on genetic variability and correlation in wild grape accessions were carried out in the most favourable regions of Leh district of Jammu and Kashmir. Fifty wild grape accessions from five different villages of the district were marked and evaluated for important morphological traits i.e. yield and quality parameters. Data on various vegetative, fruit physical and fruit chemical characters were taken. Significant variations were observed for all the characters studied except number of seeds per berry. High genotypic coefficient of variance (GCV) and phenotypic coefficient of variance (PCV) were recorded for yield (21.73 and 22.81), yield efficiency (41.19 and 52.73), bunch weight (21.07 and 21.23), number of berries per bunch (22.31 and 25.28), berry length (21.69 and 22.07), berry weight (21.13 and 21.28) and total sugars (22.69 and 22.70). Out of twenty studied characters, thirteen characters registered high heritability estimates, while five recorded moderate heritability estimates and number of seeds per berry and acidity showed low heritability estimates. However, cane length (59.40), leaf area (31.43), bunch weight (43.16), number of berries per bunch (27.18) and TSS/acid ratio (25.81) exhibited high genetic advance as percentage of mean indicating additive gene effect. Fruit or berry yield was positively and significantly correlated with bunch length (0.652), bunch breadth (0.584), bunch weight (0.946), number of berries per bunch (0.672), berry breadth (0.363) and number of seeds per berry (0.612). This study revealed that the characters such as yield, bunch length, bunch weight, number of bunch per vine, berry weight, number of berries per bunch, total soluble solids and total sugars are the most important traits for selecting best grape accessions

Comprehensive mechanism of gene silencing and its role in plant growth and development

Gene silencing is a negative feedback mechanism that regulates gene expression to define cell fate and also regulates metabolism and gene expression throughout the life of an organism. In plants, gene silencing occurs via transcriptional gene silencing (TGS) and post-transcriptional gene silencing (PTGS). TGS obscures transcription via the methylation of 5′ untranslated region (5′UTR), whereas PTGS causes the methylation of a coding region to result in transcript degradation. In this review, we summarized the history and molecular mechanisms of gene silencing and underlined its specific role in plant growth and crop production

Central Pb+Pb Collisions at 158 A GeV/c Studied by Pion-Pion Interferometry

Two-particle correlations have been measured for identified negative pions from central 158 AGeV Pb+Pb collisions and fitted radii of about 7 fm in all dimensions have been obtained. A multi-dimensional study of the radii as a function of kT is presented, including a full correction for the resolution effects of the apparatus. The cross term Rout-long of the standard fit in the Longitudinally CoMoving System (LCMS) and the vl parameter of the generalised Yano-Koonin fit are compatible with 0, suggesting that the source undergoes a boost invariant expansion. The shapes of the correlation functions in Qinv and Qspace have been analyzed in detail. They are not Gaussian but better represented by exponentials. As a consequence, fitting Gaussians to these correlation functions may produce different radii depending on the acceptance of the experimental setup used for the measurement.Comment: 13 pages including 10 figure

Search for Disoriented Chiral Condensates in 158 AGeV Pb+Pb Collisions

The restoration of chiral symmetry and its subsequent breaking through a phase transition has been predicted to create regions of Disoriented Chiral Condensates (DCC). This phenomenon has been predicted to cause anomalous fluctuations in the relative production of charged and neutral pions in high-energy hadronic and nuclear collisions. The WA98 experiment has been used to measure charged and photon multiplicities in the central region of 158 AGeV Pb+Pb collisions at the CERN SPS. In a sample of 212646 events, no clear DCC signal can be distinguished. Using a simple DCC model, we have set a 90% C.L. upper limit on the maximum DCC production allowed by the data.Comment: 20 Pages, LaTeX, uses elsart.cls, 8 eps figures included, submitted to Physics Letters

First Measurement of Z/gamma* Production in Compton Scattering of Quasi-real Photons

We report the first observation of Z/gamma* production in Compton scattering of quasi-real photons. This is a subprocess of the reaction e+e- to e+e-Z/gamma*, where one of the final state electrons is undetected. Approximately 55 pb-1 of data collected in the year 1997 at an e+e- centre-of-mass energy of 183 GeV with the OPAL detector at LEP have been analysed. The Z/gamma* from Compton scattering has been detected in the hadronic decay channel. Within well defined kinematic bounds, we measure the product of cross-section and Z/gamma* branching ratio to hadrons to be (0.9+-0.3+-0.1) pb for events with a hadronic mass larger than 60 GeV, dominated by (e)eZ production. In the hadronic mass region between 5 GeV and 60 GeV, dominated by (e)egamma* production, this product is found to be (4.1+-1.6+-0.6) pb. Our results agree with the predictions of two Monte Carlo event generators, grc4f and PYTHIA.Comment: 18 pages, LaTeX, 5 eps figures included, submitted to Physics Letters

Search for Higgs Bosons in e+e- Collisions at 183 GeV

The data collected by the OPAL experiment at sqrts=183 GeV were used to search for Higgs bosons which are predicted by the Standard Model and various extensions, such as general models with two Higgs field doublets and the Minimal Supersymmetric Standard Model (MSSM). The data correspond to an integrated luminosity of approximately 54pb-1. None of the searches for neutral and charged Higgs bosons have revealed an excess of events beyond the expected background. This negative outcome, in combination with similar results from searches at lower energies, leads to new limits for the Higgs boson masses and other model parameters. In particular, the 95% confidence level lower limit for the mass of the Standard Model Higgs boson is 88.3 GeV. Charged Higgs bosons can be excluded for masses up to 59.5 GeV. In the MSSM, mh > 70.5 GeV and mA > 72.0 GeV are obtained for tan{beta}>1, no and maximal scalar top mixing and soft SUSY-breaking masses of 1 TeV. The range 0.8 < tanb < 1.9 is excluded for minimal scalar top mixing and m{top} < 175 GeV. More general scans of the MSSM parameter space are also considered.Comment: 49 pages. LaTeX, including 33 eps figures, submitted to European Physical Journal

A Measurement of the Product Branching Ratio f(b->Lambda_b).BR(Lambda_b->Lambda X) in Z0 Decays

The product branching ratio, f(b->Lambda_b).BR(Lambda_b->Lambda X), where Lambda_b denotes any weakly-decaying b-baryon, has been measured using the OPAL detector at LEP. Lambda_b are selected by the presence of energetic Lambda particles in bottom events tagged by the presence of displaced secondary vertices. A fit to the momenta of the Lambda particles separates signal from B meson and fragmentation backgrounds. The measured product branching ratio is f(b->Lambda_b).BR(Lambda_b->Lambda X) = (2.67+-0.38(stat)+0.67-0.60(sys))% Combined with a previous OPAL measurement, one obtains f(b->Lambda_b).BR(Lambda_b->Lambda X) = (3.50+-0.32(stat)+-0.35(sys))%.Comment: 16 pages, LaTeX, 3 eps figs included, submitted to the European Physical Journal