GUEST EDITORIAL

Nanoelectronic devices of various kinds of are essential for VLSI circuits. The struggle to follow Moore’s law is becoming increasingly difficult and complex, requiring multitudinous novel approaches in order to continue decreasing dimensions of the devices which are already firmly established in the nano-world. As an example, the most advanced state of the art VLSI’s (microprocessors) currently can contain more than 50 billion transistors per chip. As far as the actual physical dimensions are concerned, in 2021 the IBM company announced their 2 nm chip.The efforts behind such achievements are enormous. This special issue on advanced planar nanoelectronics investigates some points of interest related to the physics of such devices, as well as their simulation, thus giving its contribution to the existing trends in this rapidly evolving and constantly expanding field

Structure-property Characterisation at Nanoscale using In-situ TEM and SEM

In-situ electron microscopy is an emerging technique for real time visualisation of micro-structural changes of a specimen under some applied constraints inside microscope. In this study, in-situ nanoindentation experimentation on a carbon nanocoil inside transmission electron microscope has been reported. The elastic modulus of the carbon nanocoil is found to be 177 GPa. Similar experiments are also carried out on carbon nanotubes, but force response of carbon nanotubes is beyond the limit of sensors presently available. The present study also reports the in-situ dissolution behavior of the secondary phases of a 7xxx series aluminum alloy under high vacuum condition in scanning electron microscope (SEM) in the temperature range of 350 °C to 400 °C. We report for the first time using in-situ SEM technique that dissolution of the MgZn2-base phase present as eutectic and divorced eutectic forms could start at a temperature as low as 300 °C, although the usual homogenisation temperature of such alloys is always > 450 °C. Furthermore, the kinetics of dissolution of such phases, particularly when present in fine eutectic phase mixture, is significantly faster than what is observed under atmospheric pressure. It has been found that modification of surface composition under high vacuum condition plays a key role in the low temperature dissolution processes. It has further been found that the dissolution process does not start with the thinning of the IDC phase as proposed for Al-Zn-Mg-Cu alloys, rather it occurs by a combination of ‘spheroidisation’ and thinning process called ‘the thinning, discontinuation, and full dissolution’ (TDFD) mechanism. Results of the in-stu experiments under high vacuum are compared with the ex-situ dissolution experiments under normal atmospheric pressure

Growth analysis of short duration transplanted Aus rice (cv. Parija) under three agronomic practices

An experiment was conducted at the Agronomy Field Laboratory, Bangladesh Agricultural University, Mymensingh to investigate the growth of short duration transplanted Aus rice (cv. Parija) under three agronomic practices. The study comprised of two nursery seeding densities viz. 40 and 80 g seeds m-2, three ages of seedlings viz. 20, 30 and 40-day old, and three levels of seedlings hill-1 viz. 2, 4 and 6 seedlings hill-1. The experiment was laid out in a Randomized Complete Block Design with three replications. For individual treatment effects, the highest plant height, number of tillers hill-1, total dry matter, leaf area index and crop growth rate were found when seedlings were raised @ 40g seed m-2 and 30-day old seedlings were transplanted @4 seedlings hill-1. In interaction, the highest number of tillers hill-1 (13.00) and total dry matter (22.93 g) at 45 DAT, and crop growth rate (6.71 g m-2 day-1) at 15-30 DAT were obtained from the interaction among 40 g seed m-2 × 30-day old seedlings × 4 seedlings hill-1. On the other hand, the tallest plant (73.27 cm) at 45 DAT was found from the interaction among 80 g seed m-2 × 30-day old seedlings × 4 seedlings hill-1, while the highest leaf area index (2.87) was recorded from the interaction of 40 g seed m-2 × 30-day old seedlings × 2 seedlings hill-1 at 50 DAT. Considering both the significant individual and interaction treatment effects on the growth parameters, the use of 40 g seed m-2 × 30-day old seedlings × 4 seedlings hill-1 could improve the growth performance of short duration transplanted Aus rice (cv. Parija). Therefore, a nursery seeding density of 40 g seed m-2 and 30-day old seedlings transplanting with 4 seedlings hill-1 appears as the promising combination in respect of growth performance of short duration transplanted Aus rice (cv. Parija)

Study on Utility and Revival through Community approach in Sundarbans Mangrove

ABSTRACT Mangroves are salt tolerant group of tropical plants that generally grows in the inter-tidal zones of land and sea. The Sundarbans is the world's largest mangrove forest covering Ganga-Brahmaputra-Meghna delta of India and Bangladesh. It protects the coastline of Bangladesh, and West Bengal of India from different environmental catastrophes and act as means of livelihood for numbers of people of both the countries. The population of mangrove species is declining rapidly due to continuous deforestation by the wood pirates, mafias and some other causes. Mangroves are normally propagated by seeds which are usually vivipary in nature. Seeds are buoyant and hence short and long distance dispersal occurs by tidal water. Attempt was made to propagate some of the true mangrove plants artificially. Nursery was raised collecting seeds in different ways. Vegetative propagation like cutting and layering were also tried and proved successful but tedious and time consuming. Seedlings from the seeds are better option for reproduction of the endangered species as well as for other species. Community involvement is a major factor in restoration of mangroves as different livelihood activities like bagda meen (seeds of tiger prawn-Penaeus monodon) collection, crab collection, fishing from the brackish water; establishment of brick industry and funeral place in river/coast bed, and conversion of river bed for other livelihood activities not only kills many seedlings but also posed a severe threat to the mangroves. Suitable propagation technique in proper time, particularly during August to October, with active participation of adjacent village people may protect this unique mangrove forest

The Vanishing People and Vanishing Community- A Case Study in Bangladesh

Development, inequality and poverty are perhaps the most important issues in Bangladesh. Politicians, academics, NGO leaders, concern citizen

Semi-analytical modeling of Ag and Au nanoparticles and fullerene (C60) embedded gate oxide compound semiconductor MOSFET memory devices

In this paper we present an analytical simulation study of Non-volatile MOSFET memory devices with Ag/Au nanoparticles/fullerene (C60) embedded gate dielectric stacks. We considered a long channel planar MOSFET, having a multilayer SiO₂‒HfO₂ (7.5 nm)‒Ag/Au nc/C60 embedded HfO₂ (6 nm)‒HfO₂ (30 nm) gate dielectric stack. We considered three substrate materials GaN, InP and the conventional Si substrate, for use in such MOSFET NVM devices. From a semi-analytic solution of the Poisson equation, the potential and the electric fields in the substrate and the different layers of the gate oxide stack were derived. Thereafter using the WKB approximation, we have investigated the Fowler-Nordheim tunneling currents from the Si inversion layer to the embedded nanocrystal states in such devices. From our model, we simulated the write-erase characteristics, gate tunneling currents, and the transient threshold voltage shifts of the MOSFET NVM devices. The results from our model were compared with recent experimental results for Au nc and Ag nc embedded gate dielectric MOSFET memories. From the studies, the C60 embedded devices showed faster charging performance and higher charge storage, than both the metallic nc embedded devices. The nc Au embedded device displayed superior characteristics compared to the nc Ag embedded device. From the model GaN emerged as the overall better substrate material than Si and InP in terms of higher threshold voltage shift, lesser write programming voltage and better charge retention capabilities.Facultad de Ciencias ExactasInstituto de Investigaciones Fisicoquímicas Teóricas y Aplicada

Enhancement of solubility of Metaclopramide using solid dispersion technique with different carriers (HPβCD, PVP K-30)

Modern drug discovery has led to the development of drug molecules that exhibit high lipophilicity and poor water solubility, which leads to problematic bioavailability. Approaches have thus been made to enhance dissolution of poorly water soluble drugs through modifications and creation of specific formulations. Metaclopramide is an antiemetic and gastroprokinetic agent, commonly used to treat nausea and vomiting. It is absorbed well after oral administration but a significant first pass effect in some human patients may reduce systemic bioavailability to 30%.The Metaclopramide base is thus modified from Metaclopramide hydrochloride to enhance solubility .This has been achieved by the formulating in solid dispersion since Metaclopramide is poorly water soluble. Though it is absorbed well after oral administration, a significant first pass effect in some patients reduces systemic bioavailability, which can cause adverse side effects. This solid dispersion has then been used through transdermal drug delivery. Enhancement of solubility of poorly water soluble drug by solid dispersion may be attributed to particles modified characters such as particle size reduction, improved wettability, higher porosity, decreased lattice energy, amorphous state. The main objective thus includes modification of drug Metaclopramide  hydrochloride to Metaclopramide base, preparation of solid dispersion of modified Metaclopramide  base drug which has poor water solubility, experimental analysis of Metaclopramide base drug and solid dispersion products with carriers. Keywords: solubility, Metaclopramide, solid dispersion, carriers, HPβCD, PVP K-3

Differential fault attack on DEFAULT

Block cipher DEFAULT has been proposed as a differential fault analysis immune cipher at Asiacrypt 2021. In this paper, we consider the initial version of DEFAULT with no permutation involved in the last round and show that one can find the key in this version with complexity $2^{16}$ by injecting 112 faults. However, our idea does not work in the modified version of the cipher

Hydrogen Sulfide and Silicon Together Alleviate Chromium (VI) Toxicity by Modulating Morpho-Physiological and Key Antioxidant Defense Systems in Chickpea (Cicer arietinum L.) Varieties

Extensive use of chromium (Cr) in anthropogenic activities leads to Cr toxicity in plants causing serious threat to the environment. Cr toxicity impairs plant growth, development, and metabolism. In the present study, we explored the effect of NaHS [a hydrogen sulfide; (H2S), donor] and silicon (Si), alone or in combination, on two chickpea (Cicer arietinum) varieties (Pusa 2085 and Pusa Green 112), in pot conditions under Cr stress. Cr stress increased accumulation of Cr reduction of the plasma membrane (PM) H+-ATPase activity and decreased in photosynthetic pigments, essential minerals, relative water contents (RWC), and enzymatic and non-enzymatic antioxidants in both the varieties. Exogenous application of NaHS and Si on plants exposed to Cr stress mitigated the effect of Cr and enhanced the physiological and biochemical parameters by reducing Cr accumulation and oxidative stress in roots and leaves. The interactive effects of NaHS and Si showed a highly significant and positive correlation with PM H+-ATPase activity, photosynthetic pigments, essential minerals, RWC, proline content, and enzymatic antioxidant activities (catalase, peroxidase, ascorbate peroxidase, dehydroascorbate reductase, superoxide dismutase, and monodehydroascorbate reductase). A similar trend was observed for non-enzymatic antioxidant activities (ascorbic acid, glutathione, oxidized glutathione, and dehydroascorbic acid level) in leaves while oxidative damage in roots and leaves showed a negative correlation. Exogenous application of NaHS + Si could enhance Cr stress tolerance in chickpea and field studies are warranted for assessing crop yield under Cr-affected area

Cancer risk in persons with HIV/AIDS in India: a review and future directions for research

Background India has a large and evolving HIV epidemic. Little is known about cancer risk in Indian persons with HIV/AIDS (PHA) but risk is thought to be low. Methods To describe the state of knowledge about cancer patterns in Indian PHA, we reviewed reports from the international and Indian literature. Results As elsewhere, non-Hodgkin lymphomas dominate the profile of recognized cancers, with immunoblastic/large cell diffuse lymphoma being the most common type. Hodgkin lymphoma is proportionally increased, perhaps because survival with AIDS is truncated by fatal infections. In contrast, Kaposi sarcoma is rare, in association with an apparently low prevalence of Kaposi sarcoma-associated herpesvirus. If confirmed, the reasons for the low prevalence need to be understood. Cervical, anal, vulva/vaginal and penile cancers all appear to be increased in PHA, based on limited data. The association may be confounded by sexual behaviors that transmit both HIV and human papillomavirus. Head and neck tumor incidence may also be increased, an important concern since these tumors are among the most common in India. Based on limited evidence, the increase is at buccal/palatal sites, which are associated with tobacco and betel nut chewing rather than human papillomavirus. Conclusion With improving care of HIV and better management of infections, especially tuberculosis, the longer survival of PHA in India will likely increase the importance of cancer as a clinical problem in India. With the population's geographic and social diversity, India presents unique research opportunities that can be embedded in programs targeting HIV/AIDS and other public health priorities