Attribute-based authentication on the cloud for thin clients

We propose two new authentication schemes for the cloud that support private attribute-based authentication services. The basic scheme is non-anonymous attribute-based authentication scheme. The extended scheme of the basic scheme is fully anonymous attribute-based authentication scheme to realize full anonymity and unlinkability services. In the proposed schemes, a user is authenticated by the remote server if the intersection of the set of his/her assigned attributes and the server’s required attributes exceeds a satisfactory predefined level. Unlike existing attribute-based encryption and signature schemes that require the user to perform significant amount of elliptic curve bilinear pairings and modular exponentiations, and require the user to hold a significantly long decryption/signature key, in our schemes the user is not required to perform any bilinear pairings. With a fixed length private key, independent of the number of attributes, the cloud user performs only few exponentiations by which he/she is able to authenticate himself/herself to the remote server and establish a session key with the server with the condition that he/she satisfies a predefined level of the server’s attributes requirement. Therefore, our schemes are suitable for implementation on devices with limited resources. We provide the rigorous security of the proposed schemes and complexity analysis of our schemes. Finally, the security and performance comparisons of our schemes with the existing related schemes show that our schemes outperform other existing schemes.     

Significance of fruit and vegetable allergens: Possibilities of its reduction through processing

Fruit and vegetable allergies are prevalent commonly in adults, infants, and children all around the world, but more importantly in Europe and North America. The only solution is complete abstinence from the responsible food, which can be very difficult due to their presence in the form of hidden or undeclared ingredients. Various studies have shown the direct effect of processing on the secondary structure of proteins that can mitigate the allergic properties. The impact of these processing techniques on fruit and vegetable allergies have shown limited success due to the fact that they have multiple allergens that are especially heat stable. Apples, kiwi, peach, and melons are common fruits, whereas celery and carrot are the common vegetables that can result in allergic reactions for some portion of the population upon exposure.

Abbreviations: IgE: immunoglobulin E, OAS: oral allergy syndrome, nsLTP: nonspecific lipid transfer proteins, LTP: lipid transfer proteins, HPP: high-pressure processing, PEF: pulsed electric field, CD: circular dichroism, pI: isoelectric point, DBPCFCs: double-blind placebo-controlled food challenges     

Ant colony optimisation algorithm for distribution-allocation problem in a two-stage supply chain with a fixed transportation charge

In a fixed charge transportation problem, each route is associated with a fixed charge (or a fixed cost) and a transportation cost per unit transported. The presence of the fixed cost makes the problem difficult to solve, thereby requiring the use of heuristic methods. In this paper, an algorithm based on ant colony optimisation is proposed to solve the distribution-allocation problem in a two-stage supply chain with a fixed transportation cost for a route. A numerical study on benchmark problem instances has been carried out. The results obtained for the proposed algorithm have been compared with that for the genetic algorithm-based heuristic currently available in the literature. It is statistically confirmed that the proposed algorithm provides significantly better solutions.     

Effects of Ultrasonic and Microwave Processing on Avidin Assay and Secondary Structures of Egg White Protein

The effect of microwave and ultrasonic processing on the secondary structure of egg white protein was evaluated using Fourier-transform infrared spectroscopy and circular dichroism spectroscopy. The influence of these methods on avidin activity was also evaluated. Microwave treatment was performed at 60 °C, 70 °C, and 80 °C for 1, 3, and 5 min. Avidin activity was found to decrease in all the processed samples. However, the reduction in its activity was higher when treated at 80 °C. The secondary structure analysis revealed that the β-sheets increased at temperatures 60 °C and 70 °C as the processing time rose while became almost constant at 80 °C. α-helices were found to decrease with time at each of the temperatures at which microwave was applied. Turns and unordered structures remained constant. Ultrasonic processing was carried out for 1, 4, 8, 12, and 16 min. α-helices declined significantly with remarkable increase of β-sheets when samples were treated for 1 min compared to control. However, the secondary structure content did not change significantly when the duration of ultrasonication was increased, showing minimal processing capabilities of ultrasound.     

Review of conventional and novel food processing methods on food allergens

With the turn of this century, novel food processing techniques have become commercially very important because of their profound advantages over the traditional methods. These novel processing methods tend to preserve the characteristic properties of food including their organoleptic and nutritional qualities better when compared with the conventional food processing methods. During the same period of time, there is a clear rise in the populations suffering from food allergies, especially infants and children. Though, this fact is widely attributed to the changing livelihood of population in both developed and developing nations and to the introduction of new food habits with advent of novel foods and new processing techniques, their complete role is still uncertain. Under the circumstance, it is very important to understand the structural changes in the protein as food is processed to comprehend whether the specific processing technique (conventional and novel) is increasing or mitigating the allergenicity. Various modern means are now being employed to understand the conformational changes in the protein which can affect the allergenicity. In this review, the processing effects on protein structure and allergenicity are discussed along with the insinuations of recent studies and techniques for establishing a platform to investigate future pathway to reduce or eliminate allergenicity in the population.     

Processing effects on tree nut allergens: A review

“Tree nut” is a broad term for classification of nuts that include cashews, almonds, hazelnuts, etc. Reports of mild to adverse immune reactions following the consumption of these nuts has been on a rise in recent years. Currently, about 1.2–2% of the world's population suffer from sensitivity to tree nuts. The only solution is complete abstinence from the allergy causing tree nut which is not feasible in most cases due to issues like cross contamination or their presence in the form of hidden ingredients in processed foods. Various studies have shown that food processing can effectively vary the secondary structures of the allergenic protein which in turn influences their functional properties. But, the impact of these processing methods on tree nuts allergens is mixed. This review gives an update on the recent findings on how conventional and novel processing methods influence the tree nut allergens.     

Ortho‐selective vapour phase methylation of phenol over nanocrystalline ferrospinels of varying Zn2+/Mn2+ ionic composition

Ortho‐selective vapour phase methylation of phenol with methanol has been carried out over Zn_(1?x)Mn_xFe₂O₄ (x = 0, 0.25, 0.5, 0.75, 1.0) in the temperature range 423–698K in a fixed‐bed, down‐flow reactor. o‐Cresol and 2,6‐xylenol were found to be the major products. Reaction parameters were optimized over MnFe₂O₄ (MF). Maximum yields of 68.3% and 14% with selectivities of 81% and 17% were obtained for 2,6‐xylenol and o‐cresol respectively, giving a total selectivity of 98% over MnFe₂O₄ at 598K, methanol to phenol molar ratio 6, and 0.4 h^?1 weight hour space velocity. It was found that the product selectivity is greatly influenced by the acido‐basic properties of the catalysts. o‐Cresol formation is favoured over catalysts with weak acid sites whereas formation of 2,6‐xylenol occurs in the presence of stronger acid sites. Catalyst characterization has been carried out by X‐ray diffraction, infrared spectroscopy and ammonia desorption methods. X‐ray diffractograms were used to determine the unit cell length and correlated with the acidity and catalytic activity of the spinel systems. IR absorption bands observed around 700 cm^?1 and 500 cm^?1 are respectively attributed to the tetrahedral and octahedral metal‐oxygen stretching mode of the spinel. Shifting of bands towards lower wave numbers is correlated with composition and acidity of the spinel systems. The results are discussed on the basis of the Zn²⁺ and Mn²⁺ composition and acidity of the spinel systems. Copyright © 2004 Society of Chemical Industry     

Kinetic studies and Mechanism Evolution of the Ammoxidation of 3‐picoline Over V2O5/ZrO2 Catalyst

A kinetic investigation of the ammoxidation of 3‐picoline to 3‐cyanopyrdine has been studied over V₂O₅/ZRO₂ Catalyst in a differential flow reactor in the temperature range 573‐683 K. The partial pressures of 3‐picoline, oxygen and ammonia were varied and rates were measured for the formation of 3‐cyanopyridine. Kinetics studies reveal that the mechanism of the reaction is of the “Redox” type. The rate equation deduced, assuming a study state involving a three stage oxidation‐reduction process, represented the data most satisfactorily for conversion of 3‐picoline to nicotinonitrile. Catalysts have been characterized using IR, XRD, ESR, Surface area and ammonia desorption methods with a view to understanding the structure and nature of bonding over the surface of the catalyst. A tentative mechanism of the process has been suggested.     

Effect of High Electric Field on Secondary Structure of Wheat Gluten

The effect of a high electric field on secondary structure conformation of fully hydrated (45.65% wet basis) gluten protein was studied by Fourier transform infrared spectroscopy. Three experimental conditions were evaluated including electric field intensity of 0 kV (no treatment), 3.5 kV, and 7kV and treatment time of 30, 60, and 90 min. Fourier transform infrared spectra of treated and non-treated hydrated gluten protein revealed that high electric field treatment resulted in irreversible changes in the secondary structures. For the 30 min treatment no variation was observed for electric field intensities 0 and 7 kV; but at 3.5 kV it showed slight reorganization and structural conversion of secondary structures. No variation in spectral pattern was observed for all the high electric field treatments for 60 min but major secondary structure reorganization took place for high electric field treatment at 90 min. Curve-fitting using Gaussian band shapes and principal component analysis further supported the results.     

A Comprehensive Review on Kiwifruit Allergy: Pathogenesis,Diagnosis, Management,and Potential Modification of Allergens Through Processing

Kiwifruit is rich in bioactive components including dietary fibers, carbohydrates, natural sugars, vitamins, minerals, omega‐3 fatty acids, and antioxidants. These components are beneficial to boost the human immune system and prevent cancer and heart diseases. However, kiwifruit is emerging as one of the most common elicitors of food allergies worldwide. Kiwifruit allergy results from an abnormal immune response to kiwifruit proteins and occur after consuming this fruit. Symptoms range from the oral allergy syndrome (OAS) to the life‐threatening anaphylaxis. Thirteen different allergens have been identified in green kiwifruit and, among these allergens, Act d 1, Act d 2, Act d 8, Act d 11, and Act d 12 are defined as the “major allergens.” Act d 1 and Act d 2 are ripening‐related allergens and are found in abundance in fully ripe kiwifruit. Structures of several kiwifruit allergens may be altered under high temperatures or strong acidic conditions. This review discusses the pathogenesis, clinical features, and diagnosis of kiwifruit allergy and evaluates food processing methods including thermal, ultrasound, and chemical processing which may be used to reduce the allergenicity of kiwifruit. Management and medical treatments for kiwifruit allergy are also summarized.