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Present investigation was carried out to study the effect of stress on ovarian follicular activity in postpartum acyclic Sahiwal cows during hot-humid months. Postpartum ovarian activity was monitored using trans-rectal ultrasound scanning on alternate days beginning between day 60 and 90 postpartum in Sahiwal cows (n=16) up to next 21 days.Daily maximum temperature and relative humidity was recorded andtemperature-humidity index (THI)was calculated during study period. Six animals (37.5 %) showed presence of dominant follicle (≥10 mm, cyclic) and 10 animals (62.5 %) were classified as acyclic (ovarian follicle < 10 mm diameter). Present study demonstrated that as the value of THI reduced, the mean follicular diameter proportionately increased and vice versa. Based on the findings of present study, it may be concluded that development of ovarian follicle is highly affected by THI value during hot-humid season in Sahiwal cows and the reproductive performance of animal may be predicted using THI values.

Phytophthora infestans causing late blight is one of the most devastating tomato and potato disease that caused considerable yield losses globally including Pakistan. Due to repeated and injudicious synthetic fungicides applications for the control of late blight of potato, the fungicide resistance in P. infestans led to persistence and surveillance late blight of potato. The study was carried out to evaluate the efficacy of Garlic (Allium sativum), Neem (Azadirachta indica), Turmeric (Curcuma longa), Mint (Mentha) at 10%, 20% and 30% concentration as bio-fungicides against late blight of potato. In-vitro effect of plant extracts of A. sativum, A. indica, C. longa and Mentha were evaluated on percent inhibition and radial growth of pathogen. A. sativum and A. indica at 30% concentration was found more effective in minimizing the mycelial growth of P. infestans with inhibition of 58.4% and 43.9% respectively as compared to control. In the greenhouse trial, overall potato late blight disease incidence was minimum 5.81% where A. sativum extract was used followed by A. indica at 30% concentration resulted 8.45% incidence as compared to control 61.18%. Furthermore, the 30% aqueous extracts of A. sativum found highly effective against late blight disease with 15.4% severity, as compared to control with 54.13% disease coverage. Application of A. sativum and A. indica aqueous plant extracts with a concentration of 30% was found most promising and effective measure against late blight pathogen. Study provides environmentally benign mileage in organic vegetable production against hazardous synthetic agro-chemicals.

Topochemical polymerizations are solid-state reactions driven by the alignment of monomers in the crystalline state. The molecular confinement in the monomer crystal lattice offers precise control over the tacticity, packing and crystallinity of the polymer formed in the topochemical reaction. As topochemical reactions occur under solvent- and catalyst-free conditions, giving products in high yield and selectivity/specificity that do not require tedious chromatographic purification, topochemical polymerizations are highly attractive over traditional solution-phase polymer synthesis. By this method, polymers having sophisticated structures and desired topologies can be availed. Often, such ordered packing confers attractive properties to the topochemically-synthesized polymers. Diverse categories of topochemical polymerizations are known, such as polymerizations via [2+2], [4+4], [4+2], and [3+2] cycloadditions, and polymerization of diynes, triynes, dienes, trienes, and quinodimethanes, each of which proceed under suitable stimuli like heat, light or pressure. Each class of these reactions requires a unique packing arrangement of the corresponding monomers for the smooth reaction and produces polymers with distinct properties. This review is penned with the intent of bringing all the types of topochemical polymerizations into a single platform and communicating the versatility of these lattice-controlled polymerizations. We present a brief history of the development of each category and comprehensively review the topochemical synthesis of fully-organic polymers reported in the last twenty years, particularly in crystals. We mainly focus on the various molecular designs and crystal engineering strategies adopted to align monomers in a suitable orientation for polymerization. Finally, we analyze the current challenges and future perspectives in this research field.

We report 11 simple halobenzyl alcohols, each comprising of only 16 atoms, as organogelators for aliphatic hydrocarbon solvents. Comparison of PXRD profiles of wet gels and xerogels with the simulated profiles from the single crystal XRD data confirmed that the molecular packing in gels and crystals are identical. Therefore single crystal X-ray structures were analyzed to understand the molecular level interactions involved in the self-assembly in gel state. Each of these compounds undergoes a faster linear assembly along the crystallographic direction associated with the OH⋯O hydrogen bond and a supplementary non-covalent interaction (NCI). In directions perpendicular to the direction of OH⋯O Hydrogen bonding, molecules associate through various relatively weaker NCIs. Notably, halogen bonds, X⋯X, C–H⋯X interactions play major role in the lateral growth. In the case of gels, the linear growth is faster than lateral growth leading to the formation of long fibers, which entangles to a 3D fibrous network. This study reveals that halogen atoms in halobenzyl alcohols impart molecular features that contribute to their self-assembly in solution and hence in gelation.

There are so many communication schemes available today for the communication between authorized remote users and servers over an insecure network. These types of authentication schemes generally use the password for the authentication. To have the communication between remote users and servers, many researchers have proposed remote user authentication techniques using the smart card. The advantage of using the smart card is the storage availability and the computation speed. In many proposed protocols, authors argued that their protocol is secure and efficient against any type of attack. Unfortunately, many model fails against the off-line password guessing attack, and with these schemes, wrong password detection is not easy. Also, as many schemes use RSA cryptosystem to offer the authentication, it adds computational overhead to system which is not suitable for the smart card applications. In this paper, efficient smart card-based authentication protocol using elliptic curve cryptography (ECC) is proposed. This proposed scheme has faster computation as compared to the available schemes, and it is secure against variable attacks.

IoT is spreading rapidly from industry to domestic application such as home automation and gathering sensitive data through IoT devices hence the security of these devices and the data transmission is of great importance. Because of the resource constraint devices, lightweight cryptographic protocol plays an important role. Therefore, implementing the zero-knowledge proof along with the hyper elliptic curve cryptography enhances the security and efficiency in the resource constraint devices.

Nowadays, cloud computing has become a significant area for the business due to the high demand of people engaging in E-commerce. E-commerce applications are very popular for conducting business via the Internet which includes online banking, bill payment, and purchasing goods, etc. E-commerce is said to be more straightforward, easier to use, intuitive, and less threatening. The rapid development of the Internet over the past decade appeared to have facilitated an increase in the incidents of online attacks. One such powerful and harmful attack is the denial-of-service (DoS) attack, and hence, protecting the entities from such attacks is essential. Therefore, an effective DoS attack detection technique is required in the E-commerce transactions to offer security in this platform. Accordingly, in this paper, a technique is developed for DoS attack detection in the E-commerce transactions by proposing glowworm swarm optimization-based support vector neural network (GSO-SVNN)-based authorization. The security will be provided with elliptic-curve cryptography (ECC) and hashing function to show the strength of the security protocol against a DoS attacks. The performance of the proposed technique is evaluated using four metrics, like accuracy, precision, recall, and false positive rate (FPR).

In recent years, Electronic Commerce (E-commerce) applications are attracting many users and merchants to conduct their daily business online which includes payment of bills, online banking, buying tickets and purchasing goods etc. E-commerce transaction security is a major concern for E-commerce websites along with its customers. The basic requirements for any E-commerce transaction are privacy, authentication, integrity and non-repudiation. In this paper, a transaction processing system (TPS) for E-commerce by using a Blockchain technology, zero-knowledge proof and modified elliptic curve cryptography encryption is proposed. Also a denial of service attack detection model for the E-commerce system is proposed which take care of the DoS attack during E-commerce transactions.

Diarrhea due to Escherichia coli is one of the major economic concerns of bovine industry in the first few weeks after birth. The present study was carried out for characterization of virulence traits of Escherichia coli associated with diarrhea in calves less than 3 months of age and their antimicrobial profiling. Escherichia coli isolates (700) were recovered in this study, which belonged to 25 different serogroups out of which O2 and O6 were most predominant. The isolates were screened for 7 virulence genes, viz. sta, stx1, stx2, lt, f5, f41 and eae. Out of 700 isolates, 65 (9.2%) carried virulence genes either alone (f5, eae, f41, sta, stx1 and stx2) or in different combinations (f41/sta, sta/lt, stx1/eae and f5/stx2). Based on the presence of virulence factors, these isolates were classified as Shiga-toxin producing E. coli (27), enterotoxigenic E. coli (20), enteropathogenic E. coli (15) and 3 were unclassified. These 65 isolates were resistant to commonly used antibacterial agents like amoxicillin, ceftriaxone, cephalexin, cloxacillin, enrofloxacin and gentamicin. Multidrug resistance was also observed in 84.6% of them.This study reveals that PCR based detection of E. coli virotypes can be used in diagnosis and epidemiological studies. Also increasing multidrug resistance for most of the commonly used antibiotics is a matter of concern.

In the public key cryptography infrastructure of electronic commerce (E-commerce), use of the Rivest, Shamir, and Adleman (RSA) algorithm is very common. Due to the security requirements, the necessary key size of RSA is increasing exponentially. Because of this large key size, it is not convenient to use RSA in resource-constrained applications where computational speed, storage and bandwidth are limited. Elliptic Curve Cryptography (ECC) is the best alternative to the traditional RSA. ECC provides the same level of security as RSA but with reduced key size. The most important factor in the use of ECC is the selection of the correct elliptic curve. There are different types of elliptic curves suggested by various standards. The selection of the curve is dependent on various parameters, such as prime field size, the shape of the curve, etc. In this paper, sets of elliptic curves recommended by different standards for cryptography are selected, and the selected curves are analysed, focusing on the performance and security features. The performance of each curve is measured in terms of computation time. The analysis is performed by considering each curve for the implementation of the Elliptic Curve Diffie-Hellman (ECDH) algorithm and the Elliptic Curve Digital Signature Algorithm (ECDSA). The comparative table of selected curves is arranged according to the computation time taken by each curve to perform various operations when used for the ECC algorithms.

LaFeO3 (LFO) nanoparticles were prepared by microwave-assisted sol–gel combustion method with an aid of glycine as fuel. The calcined LFO sample was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy, scanning electron microscopy (SEM), EDAX and UV–Vis absorption spectroscopy. Single-phase orthorhombic structure is confirmed by XRD, and data is well fitted using Rietveld refinement by Full-Prof suite. FTIR study displays vibrational modes related to orthoferrites perovskite LaFeO3. SEM images depict fine particles size, and stoichiometry of La, Fe and O in LFO is verified by EDAX. The photodegradation behavior of LFO was evaluated by the photocatalytic decolorization of the methylene blue under natural light as well as by UV irradiation for different time. To check the potential of LaFeO3 as dielectric, dielectric constant as a function of frequency and temperature was studied. Dielectric constant is found to decrease with increase in frequency indicates dispersive behavior in low-frequency region. Temperature versus dielectric constant plots for LFO at 100 kHz give dielectric anomaly around 450 °C. This anomaly may be due to antiferromagnetic transition (T N) temperature of LFO. The present study depicts the potential of LFO to use as efficient photocatalyst and applicable dielectric materials. Very good quality and single-phase LaFeO3 (LFO) nanoparticles were prepared first time by microwave-assisted sol–gel combustion method with an aid of glycine as fuel. The photodegradation behavior of LFO was evaluated by the photocatalytic decolorization of the methylene blue (MB) under UV–visible light irradiation. Qualitative understating of correlation between photodegradation ability and dielectric behavior of LFO was established. The potential of LaFeO3 as efficient photocatalyst and dielectric materials is investigated in the present study.

In present work, NiFe2O4(NFO), ZnFe2O4 (ZFO) and Ni0.5Zn0.5Fe2O4 (NZFO) are synthesized by microwave assisted co-precipitation route. Their structural properties are confirmed by X-ray diffraction and data is fitted through Reitveld refinement using Full-Prof software suite. After refinement, the systematic crystal structures of NFO, ZFO and NZFO compounds are generated using output .cif file by VESTA (Visualization for Electronic and Structural Analysis) program. Structural parameters obtained after refinement and unit cell construction, are systematically tabulated. Room temperature frequency dependence dielectric properties are studied. We found enhanced values of dielectric constant for NZFO than individual NFO and ZFO phases. For NZFO sample, greater electron exchange between Fe2+ and Fe3+ which enhances polarization and dielectric constant.

In present work, multiferroic BiFeO3 was synthesized by hydrothermal route. The rhombohedral structure was confirmed X-ray diffraction pattern and data fitted with Reitveld refinement using Full-Prof software suite. SEM micrograph shows flake like morphology. Frequency and temperature dependence of dielectric constant and dielectric loss were studied and detected enhancement in dielectric constant. The magnetic measurement indicates antiferromagnetic nature of BFO. P-E curve shows ferroelectic hysteresis loop with remanent polarization (2Pr) 0.3518 µC/cm2. The dielectric anomaly observed near TN can be assigned to magnetoelectric coupling which is useful in device application.

Silver nanoparticles incorporated polyaniline composites were obtained through the chemical oxidation of aniline monomer in presence of pre synthesized Ag nanoparticles. D-CSA was used as the dopant acid which formed a template for the heterogeneous growth of polyaniline on the surface of silver nanoparticles. XRD, UV-Visible data and TEM image confirm the formation of the nanocomposite. The electrical results show superior properties than that of the pristine due to the effect of the nanoparticles.