Swift developments in nanotechnology have prominently encouraged innovative discoveries across many fields. Carbon-based nanomaterials have emerged as promising platforms for a broad range of ...applications due to their unique mechanical, electronic, and biological properties. Carbon nanostructures (CNSs) such as fullerene, carbon nanotubes (CNTs), graphene and diamond-like carbon (DLC) have been demonstrated to have potent broad-spectrum antibacterial activities toward pathogens. In order to ensure the safe and effective integration of these structures as antibacterial agents into biomaterials, the specific mechanisms that govern the antibacterial activity of CNSs need to be understood, yet it is challenging to decouple individual and synergistic contributions of physical, chemical and electrical effects of CNSs on cells. In this article, recent progress in this area is reviewed, with a focus on the interaction between different families of carbon nanostructures and microorganisms to evaluate their bactericidal performance.
Enhancing crop productivity and their nutritional quality are the key components and primary focus of crop improvement strategy for fulfilling future food demand and improving human health. Grain ...filling and endosperm development are the key determinants of grain yield and nutritional quality. GRAIN WIDTH and WEIGHT2 (GW2) gene encodes a RING-type E3 ubiquitin ligase and determines the grain weight in cereal crops. Here we report GW2 knockout (KO) mutants in Indica (var. MTU1010) through CRISPR/Cas9 genome editing. The endosperm of GW2-KO mutant seed displays a thick aleurone layer with enhanced grain protein content. Further the loss of function of OsGW2 results in improved accumulation of essential dietary minerals (Fe, Zn, K, P, Ca) in the endosperm of rice grain. Additionally, the mutants displayed an early growth vigour phenotype with an improved root and shoot architecture. The hull morphology of GW2-KO lines also showed improved, grain filling thereby promoting larger grain architecture. Together, our findings indicate that GW2 may serve as a key regulator of improved grain architecture, grain nutritional quality and an important modulator of plant morphology. The study offers a strategy for the development of improved rice cultivars with enriched nutritional quality and its possible implementation in other cereals as well.
Diabetes, a major lifestyle disorder, has become a global burden, and the prevalence rates are rising steeply in developing economies. Rapid socioeconomic transition with urbanization and ...industrialization are the main causes for the global diabetes epidemic. Among developing economies, the highest increase in number of people with diabetes is in China followed by India. In India, the epidemic of diabetes continue to increase and is experiencing a shift in diabetes prevalence from urban to rural areas, the affluent to the less privileged and from older to younger people. Diabetes is a progressive disorder leading to complications, which are broadly divided into small vessel or microvascular disease and large vessel or macrovascular disease. Microvascular complications affect the inner part of the eye-the retina known as diabetic retinopathy, the kidney termed as diabetic nephropathy and the peripheral nerves termed as diabetic neuropathy. The macrovascular complications affect the heart, the brain and the peripheral arteries termed as cardiovascular disease, cerebrovascular disease and peripheral vascular disease, respectively. Given the lifelong expenditure associated with diabetes and its complications, individuals, families and the society are unable to cope with the economic, emotional and social disease burden due to diabetes. The economic burden of diabetes can be reduced by providing universal healthcare coverage, access to affordable medicines and early detection and treatment of the disorder. This emphasizes the need for a multi-prolonged strategy to minimize the burden of diabetes and its complications.
Silver nanoparticles are one of the most beneficial forms of heavy metals in nanotechnology applications. Due to its exceptional antimicrobial properties, low electrical and thermal resistance, and ...surface plasmon resonance, silver nanoparticles are used in a wide variety of products, including consumer goods, healthcare, catalysts, electronics, and analytical equipment. As the production and applications of silver nanoparticles containing products increase daily, the environmental pollution due to silver nanoparticles release is increasing and affecting especially the aqueous ecosystem. Silver nanoparticles can kill useful bacteria in soil and water, and bioaccumulate in living organisms even at low concentrations from 10−2 to 10 μg/mL silver can show antibacterial effect. On the other hand, the maximum silver discharge limit into freshwater is 0.1 μg/L and 3.2 μg/L for Australia and the USA, respectively. To reduce its toxic consequences and meet the regulatory guidelines, it is crucial to remove silver nanoparticles from wastewater before it is discharged into other water streams. Several technologies are available to remove silver nanoparticles, but the adsorption process using low-cost adsorbents is a promising alternative to mitigate silver nanoparticle pollution in the bulk stage. As one of the low-cost adsorbents, biochar produced from the biomass waste could be a suitable adsorbent. This review focuses on collating the latest evidence on silver nanoparticle production, applications, environmental consequences, and cost-effective technological approaches for silver removal from wastewater.
•Silver nanoparticles and ions are toxic to living organisms.•Adsorption is a sustainable process for silver removal from wastewater.•Silver adsorption by low-cost biochar is efficient in a wide range of conditions.•Modification of biochar properties enhance adsorption rate and reusability.•Biochar-graphene composites demonstrate high silver adsorption.
Campylobacter jejuni
is one of the most common bacterial causes of human gastroenterocolitis worldwide, leading to diarrhea and other serious post-infectious complications. Probiotics form an ...attractive alternative intervention strategy for most of the enteric infections. However, the role of probiotics in
C. jejuni
infections requires detailed investigations in order to delineate the probiotic strains that are effective against
C. jejuni
. Although there are several biological mechanisms involved in the inhibition of pathogenic bacterial growth, the strains of probiotics and their mechanisms of actions through which they combat
C. jejuni
invasion have not been studied in greater detail. This mini review details the factors that are involved in the colonization and establishment of
C. jejuni
infection, with special reference to chickens, the natural host of
C. jejuni
, and the studies that have investigated the effect of different probiotic strains against
C. jejuni
colonization and growth. This review has collated the studies conducted using probiotics to inhibit
C. jejuni
colonization and growth to date to provide a collective knowledge about the role of probiotics as an alternative intervention strategy for campylobacteriosis.
This brief describes the two unique Fractional Order (FO) speed controllers' FOPI and FOPI design and validation for the induction motor drive. The detuning of the conventional PI controller issues ...under machine parameter variations and low speed operating regions are overcome by the proposed two types of FO speed controllers. This brief presents the novel FO controller design procedure for the Voltage Source Inverter (VSI) fed IM. The actual FO VSI fed IM transfer function model is identified using the chirp signal injection method with the Hardware-In-Loop (HIL) system for the laboratory prototype. The parameter variation is subjected to different stator winding resistance machines of the same rating. The rotor inertia change of up to eight times the no-load value is incorporated to investigate the robust performance of these speed controllers under dynamic operating conditions. The performance of the designed <inline-formula> <tex-math notation="LaTeX">FOPI </tex-math></inline-formula> and <inline-formula> <tex-math notation="LaTeX">FOPI </tex-math></inline-formula> controllers are analyzed at low speeds. The results show the supremacy of the <inline-formula> <tex-math notation="LaTeX">FOPI </tex-math></inline-formula> controller over the <inline-formula> <tex-math notation="LaTeX">FOPI </tex-math></inline-formula> and PI under the same stability boundary limits. The experimental validation of these controllers is provided.
Ageing population and a multitude of neurological and cardiovascular illnesses that cannot be mitigated by medication alone have resulted in a significant growth in the number of patients that ...require implantable electronic devices. These range from sensors, gastric and cardiac pacemakers, cardioverter defibrillators, to deep brain, nerve, and bone stimulators. Long-term implants present specific engineering challenges, including low energy consumption and stable performance. Resorbable electronics may offer excellent short-term performance without the need for surgical removal. However, most electronic materials have poor bio- and cytocompatibility, resulting in immune reactions and infections. This paper reviews the current situation and highlights challenges for future advancements.
This paper presents an improved direct torque control (DTC) method for an asymmetrical six-phase induction motor using a two-level six-phase inverter. As is well known, a simple extension of ...three-phase DTC technique to an asymmetrical six-phase motor, using large vectors only, introduces significant current harmonics of the order 6 n±1 (n = 1, 3, 5,...), which are mapped into the nonflux/torque producing (xy) plane. These harmonics cause only losses in the motor winding as they do not take part in torque production. Hence, a number of different improved DTC techniques have been developed in the past for multiphase motor drives. The paper takes one such DTC method as the starting point and improves it further by using the concept of virtual voltage vectors. Developed vector selection algorithm, based on two virtual voltage vectors, requires the information on position of the flux in the auxiliary (xy) subspace and provides stator current quality commensurate with the currently available best DTC algorithm for six-phase drives. However, use of two virtual voltage vectors enables a substantial reduction of the torque ripple, which is achieved by means of a five-level torque comparator. Extensive experimentation is performed and it is shown that the reduction of the current harmonics is in essence almost the same as in another recently developed DTC scheme, based on the use of a single virtual voltage vector. However, the achieved torque ripple reduction, which is verified experimentally, makes the scheme superior when compared to the existing approaches. At the same time, developed scheme retains qualities of conventional DTC schemes, such as simple structure and fast response. Its additional beneficial feature is the easiness of implementation.
The drying behavior of a moist object subjected to convective drying is analyzed numerically by solving heat and moisture transfer equations. A 3-D numerical model is developed for the prediction of ...transient temperature and moisture distribution in a rectangular shaped moist object during the convective drying process. The heat transfer coefficients at the surfaces of the moist object are calculated with an in-house computational fluid dynamics (CFD) code. The mass transfer coefficients are then obtained from the analogy between the thermal and concentration boundary layer. Both these transfer coefficients are used for the convective boundary conditions while solving the simultaneous heat and mass transfer governing equations for the moist object. The finite volume method (FVM) with fully implicit scheme is used for discretization of the transient heat and moisture transfer governing equations. The coupling between the CFD and simultaneous heat and moisture transfer model is assumed to be one way. The effect of velocity and temperature of the drying air on the moist object are analyzed. The optimized drying time is predicted for different air inlet velocity, temperature and moisture content. The drying rate can be increased by increasing the air flow velocity. Approximately, 40% of drying time is saved while increasing the air temperature from 313 to 353
K. The importance of the inclusion of variable surface transfer coefficients with the heat and mass transfer model is justified.
Amongst alternative energy sources, photovoltaics hold a considerable promise for it is a plentiful, easily accessible and renewable source of power. Yet, the overall cost of generating electricity ...using the most advanced silicon based solar cells remains high compared to both traditional and other renewable power generation approaches. Organic thin film photovoltaics are an emerging economically competitive photovoltaic technology that combines manufacturing adaptability, low-cost processing and a lightweight, flexible device end-product. At present, however, commercial use of organic photovoltaics is hindered by low conversion efficiency and poor overall stability of the devices. Encapsulation with high barrier performance materials and structures is one of the key ways to address these issues and improve device lifetime. This paper will briefly outline the current understanding of the major degradation mechanisms, their interrelation and the internal and external factors that initiate these processes. Then, the paper will provide an overview of currently available encapsulant materials, their utility in limiting chemical (water vapor and oxygen penetration) and mechanical degradation within individual layers and device as a whole, and potential drawbacks to their application in organic photovoltaic devices.
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