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BACKGROUND One of the most vital structures in the anterior skull base surgeries is sphenoid sinus. Sellar, parasellar, suprasellar and clival lesions can be easily accessed using sphenoid sinus and is one of the most variable of all the paranasal sinuses in terms of its surrounding anatomical relationships. It also serves as a natural route for surgical entry to the middle cranial fossa and the cave of Meckel. Further, foramen of Rotundum and the canal of Vidian serve as vital gateways to important neurovascular structures, and their close proximity to the sphenoid sinus makes it necessary for the operating surgeon to have a better understanding of this anatomical ’Holy trinity’. By shedding light on this complex anatomical relationship through the course of our study, we hope to be of better assistance to the operating surgeons. METHODS 100 consecutive CT scans of the paranasal sinuses performed for any cause, were reviewed retrospectively to look for the sphenoid sinus and its anatomical relationship to the foramen rotundum and vidian canal. All the computed tomography scans were performed using Philips Ingenuity 128 slice CT scanner. 3 mm slice contiguous images were taken, and 1 mm slice reconstruction was performed. Images were reviewed in three orthogonal planes. RESULTS Based on the study, the most common type of foramen rotundum was ’Type IIB’ and the most common position of foramen rotundum in relation to sphenoid sinus based on lateral pterygoid plate was found to be the ‘online’ type. The most common variation in the Vidian canal anatomy was found to be the ‘Type II’ canal. No association was found between types of foramen rotundum and vidian canals with position of foramen rotundum. CONCLUSIONS Knowledge of the complex anatomical relationship of sphenoid sinus is important for skull base surgeries. Results of the study help us to understand the most common anatomical variations, thus aiding in better surgical outcomes.

BACKGROUND Cerebello-Pontine Angle (CPA) tumours are classified into extra-axial, intra-axial, extradural and petrous axis tumours and are usually benign. Depending on the origin of tumour and neurovascular structures displacement, CPA tumours can be asymptomatic or may present with tinnitus, vertigo or unilateral hearing loss. We wanted to study the magnetic resonance imaging (MRI) characteristics of extra axial CPA tumours and assess the incidence of extra axial CPA tumours. METHODS Patientswith signs and symptoms of CPA tumours and diagnosed with CPA tumour on computed tomography were analysed and MRI was performed with contrast study. RESULTS Tumours of CPA are not uncommon and represent 6 - 10 % of intracranial tumours. In extra axial CPA tumours, schwannoma (50 %), meningioma (30 %) are the most common; less common are arachnoid cyst (12.5 %) and epidermoid cyst (7.5 %). Schwannomas are the most common extra axial CPA tumours followed by meningioma. Schwannomas are enhancing masses most commonly arising from the vestibular nerve, usually round in shape with associated extension into internal auditory canal showing intense heterogeneous enhancement; meningiomas are hemispherical or oval shaped lesions with a broad attachment to the tentorium or dura mater usually shows intense homogeneous enhancement. Epidermoid cysts and arachnoid cysts appear with CSF signal intensity on all the MRI sequences; epidermoid cyst shows restriction on DWI but arachnoid cyst does not show restriction on DWI and is suppressed on FLAIR sequences. CISS image clearly demonstrates the epidermoid cyst. CONCLUSIONS MRI is the most sensitive non-invasive modality to evaluate extra axial CPA tumours. MRI helps to detect the location and describes the extension of the lesions based on their signal characteristics and contrast enhancement patterns.

Summary: A foot and mouth disease virus type A strain, isolated from an out­ break in a vaccinated herd, was compared serologically with the vaccine virus by the two-dimensional microneutralisation test and immunologically through a cross-immunity test in cattle. The antigenic diversity of the field virus from the vaccine virus as revealed by serological analysis was substantiated by lack of cross-protect ion in primo-vaccinated animals. The anamnestic response con­ sequent to infection was compared with that obtained through booster vaccination in terms of antibody levels and heterologous immunity. It was observed that anamnestic response had little effect on heterologous neutralisa­ tion, owing to the wide antigenic divergence.

In this work, we propose new constructions for zero inner-product encryption (ZIPE) and non-zero inner-product encryption (NIPE) from prime-order bilinear pairings, which are both attribute and function private in the public-key setting.

Background: Dental morphometrics is a subject of great significance in forensic odontology in identification of an individual. Use of teeth to represent a physical profile is valuable for identification of an individual. Aims and Objectives: The present study aims to assess the clinical crown length (CL) of erupted deciduous teeth and height of the child. A correlation of these parameters was attempted to arrive at a mathematical equation which would formulate a ratio of tooth CL to individual height that would support in estimating the probable height of the child. Materials and Methods: About 60 children (30 males and 30 females) of age ranged from 3–6 years were included in this study. Clinical vertical CLs of the deciduous dentition (tooth numbers 51, 52, 53, 54, and 55) were calculated using digital Vernier calipers (Aerospace Ltd., Bengaluru, Karnataka, India) on the cast models. Child height was measured using a standard measuring tape. Ratios of deciduous CL to height of the child were recorded. Linear stepwise forward regression analysis was applied to predict the probability of CL of a tooth most likely to support in prediction of physical height of the child. Results: Tabulated results showed a probable correlation between tooth CL and height of the child. Tooth CLs of deciduous upper right second molar (55) among the males, lateral incisor (52) among females, and canine (53) using the combined male and female data were statistically significant, and they approximately predicted the child height with minimal variations. Mathematically derived equations based on linear stepwise forward regression analysis using sixty children data are height prediction (derived from combined data of male and female children) = 400.558 + 90.264 (53 CL), male child height prediction (derived from data of male children) = 660.290 + 72.970 (55 CL), and female child height prediction (derived from data of female children) = −187.942 + 194.818 (52 CL). Conclusion: In conclusion, clinical vertical CL is an important parameter in prediction of individual height and possible identification of the individual. An extension of the similar technique to all the deciduous dentition using a larger group of children would probably give us the best options available among vertical CLs for prediction of the child height.

We propose new constructions for identity-based broadcast encryption (IBBE) and fuzzy identity-based encryption (FIBE) in bilinear groups of composite order. Our starting point is the IBBE scheme of Delerablee (Asiacrypt 2007) and the FIBE scheme of Herranz et al. (PKC 2010) proven secure under parameterised assumptions called generalised decisional bilinear Diffie-Hellman (GDDHE) and augmented multi-sequence of exponents Diffie-Hellman (aMSE-DDH) respectively. The two schemes are described in the prime-order pairing group. We transform the schemes into the setting of (symmetric) composite-order groups and prove security from two static assumptions (subgroup decision).

International audience; We describe two constructions of non-zero inner product encryption (NIPE) systems in the public index setting, both having ciphertexts and secret keys of constant size. Both schemes are obtained by tweaking the Boneh-Gentry-Waters broadcast encryption system (Crypto 2005) and are proved selectively secure without random oracles under previously considered assumptions in groups with a bilinear map. Our first realization builds on prime-order bilinear groups and is proved secure under the Decisional Bilinear Diffie-Hellman Exponent assumption, which is parameterized by the length n of vectors over which the inner product is defined. By moving to composite order bilinear groups, we are able to obtain security under static subgroup decision assumptions following the Déj a Q framework of Chase and Meiklejohn (Eurocrypt 2014) and its extension by Wee (TCC 2016). Our schemes are the first NIPE systems to achieve such parameters, even in the selective security setting. Moreover, they are the first proposals to feature optimally short private keys, which only consist of one group element. Our prime-order-group realization is also the first one with a deterministic key generation mechanism.

Bellare and Kohno (2004) introduced the notion of balance to quantify the resistance of a hash function h to a generic collision attack. Motivated by their work, we consider the problem of quantifying the resistance of h to a generic multicollision attack. To this end, we introduce the notion of r -balance μr(h) of h and obtain bounds on the success probability of finding an r-collision in terms of μr(h). These bounds show that for a hash function with m image points, if the number of trials q is Θ(rm([(r-1)/(r)])μr(h)) , then it is possible to find r-collisions with a significant probability of success. The behavior of random functions and the expected number of trials to obtain an r-collision is studied. These results extend and complete the earlier results obtained by Bellare and Kohno (2004) for collisions (i.e., r=2). Going beyond their work, we provide a new design criteria to provide quantifiable resistance to generic multicollision attacks. Further, we make a detailed probabilistic investigation of the variation of r-balance over the set of all functions and obtain support for the view that most functions have r -balance close to one.

We present two hierarchical identity-based encryption (HIBE) schemes, denoted as \(\mathcal{H}_{1}\) and \(\mathcal{H}_{2}\), from Type-3 pairings with constant sized ciphertexts. Scheme \(\mathcal{H}_{1}\) achieves anonymity while \(\mathcal{H}_{2}\) is non-anonymous. The constructions are obtained by extending the IBE scheme recently proposed by Jutla and Roy (Asiacrypt 2013). Security is based on the standard decisional Symmetric eXternal Diffie-Hellman (SXDH) assumption. In terms of provable security properties, previous direct constructions of constant-size ciphertext HIBE had one or more of the following drawbacks: security in the weaker model of selective-identity attacks; exponential security degradation in the depth of the HIBE; and use of non-standard assumptions. The security arguments for \(\mathcal{H}_{1}\) and \(\mathcal{H}_{2}\) avoid all of these drawbacks. Based on the current state-of-the-art, \(\mathcal{H}_{1}\) and \(\mathcal{H}_{2}\) are the schemes of choice for efficient implementation of (anonymous) HIBE constructions.

We present a new hierarchical identity-based encryption HIBE scheme with constant-size ciphertexts that can be implemented using the most efficient bilinear pairings, namely, Type-3 pairings. In addition to being fully secure, our scheme is anonymous. The HIBE is obtained by extending an asymmetric pairing based IBE scheme due to Lewko and Waters. The extension uses the approach of Boneh-Boyen-Goh to obtain constant-size ciphertexts and that of Boyen-Waters for anonymity. Security argument is based on the dual-system technique of Waters. The resulting HIBE is the only known scheme using Type-3 pairings achieving constant-size ciphertext, security against adaptive-identity attacks and anonymity under static assumptions without random oracles.

Waters, in 2009, introduced an important technique, called dual system encryption, to construct identity-based encryption (IBE) and related schemes. The resulting IBE scheme was described in the setting of symmetric pairing. A key feature of the construction is the presence of random tags in the ciphertext and decryption key. Later work by Lewko and Waters removed the tags and proceeding through composite-order pairings led to a more efficient dual system IBE scheme using asymmetric pairings whose security is based on non-standard but static assumptions. In this work, we have systematically simplified Waters 2009 IBE scheme in the setting of asymmetric pairing. The simplifications retain tags used in the original description. This leads to several variants, the first one of which is based on standard assumptions and in comparison to Waters’ original scheme reduces ciphertexts and keys by two elements each. Going through several stages of simplifications, we finally obtain a simple scheme whose security can be based on two standard assumptions and a natural and minimal extension of the decision Diffie-Hellman problem for asymmetric pairing groups. The scheme itself is also minimal in the sense that apart from the tags, both encryption and key generation use exactly one randomiser each. This final scheme is more efficient than both the previous dual system IBE scheme in the asymmetric setting due to Lewko and Waters and the more recent dual system IBE scheme due to Lewko. We extend the IBE scheme to hierarchical IBE (HIBE) and broadcast encryption (BE) schemes. Both primitives are secure in their respective full models and have better efficiencies compared to previously known schemes offering the same level and type of security.

Seroconversion studies were conducted in dogs vaccinated with rabies vaccine, of different age group, sex and breed, with a single and booster doses of cell culture Rabies vaccine. The results of the present study revealed that (i) Maternal antibodies were detected in 40% to 80% of 60 selected pet dogs. However 20% to 60% of the pet dogs did not have protective levels of antibody (0.5IU). (ii) A single dose of vaccine resulted in appreciable levels of protective antibody in 100% of pet dogs both in seronegetive and in dogs with low levels of antibody. (iii) When a booster dose was administered at twelve months period, considerable levels of antibody persisted upto twenty-four months. It can be concluded from the present study that a single dose of potent tissue culture vaccine resulted protective levels of antibody in the seronegetive dogs (0.5IU). In an Rabies endemic country like INDIA, annual booster dose of vaccine would enhance the immune response and help in the persistence of protective levels of antibody in the immunized dogs.

Three groups of crossbred calves were vaccinated with FMD vaccine only, combined FMD + rabies vaccine and rabies vaccine alone. Efficacy of the vaccines was determined by serum antibody assay at different intervals postvaccination. The results of the study indicated that the immune response of animals to a single inoculation of FMD vaccine only as well as combined FMD + rabies vaccine was unsatisfactory due to maternally derived antibodies to FMD virus antigen. However two inoculations elicited a satisfactory antibody response to FMD virus antigens in both group of animals. Rabies antigen alone as well as combined FMD + rabies antigen induced satisfactory serum antibody titres to rabies antigen. There was no significantly different serological responses in animal administered FMD vaccine only, rabies vaccine only or combined FMD + rabies vaccine.

Summary: Serological comparisons among type A Indian FMD virus isolates from different parts of the country were made using the two-dimensional microneutralisation test. Current vaccine strains and candidate vaccine strains were employed for reference. More than one distinct antigenic group in type A FMD virus could be identified. A broad antigenic spectrum was exhibited by A India 7/82 followed by A 22 India 57/79 while A India 85/79 and A Holland showed narrow spectra. The antigenic diversity among type A viruses in India indicated that a proposed candidate vaccine strain needs to be thoroughly compared with representative isolates from various Indian territories to estab­ lish its wide antigenic spectrum as required for the vast sub-continent.