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Nanofiber‐based products are widely used in the fields of public health, air/water filtration, energy storage, etc. The demand for nonwoven products is rapidly increasing especially after COVID‐19 pandemic. Electrospinning is the most popular technology to produce nanofiber‐based products from various kinds of materials in bench and commercial scales. While centrifugal spinning and electro‐centrifugal spinning are considered to be the other two well‐known technologies to fabricate nanofibers. However, their developments are restricted mainly due to the unnormalized spinning devices and spinning principles. High solution concentration and high production efficiency are the two main strengths of centrifugal spinning, but beaded fibers can be formed easily due to air perturbation or device vibration. Electro‐centrifugal spinning is formed by introducing a high voltage electrostatic field into the centrifugal spinning system, which suppresses the formation of beaded fibers and results in producing elegant nanofibers. It is believed that electrospinning can be replaced by electro‐centrifugal spinning in some specific application areas. This article gives an overview on the existing devices and the crucial processing parameters of these nanofiber technologies, also constructive suggestions are proposed to facilitate the development of centrifugal and electro‐centrifugal spinning. [ABSTRACT FROM AUTHOR]

Nanotechnology has attracted great attention from researchers in modern science because nanomaterials have innovative and superior physical, chemical, and biological properties, and they can be altered and modified accordingly. As particles get smaller, their surface area increases compared to their volume. Electrospinning is one of the advanced techniques to produce ultrathin nanofibers and membranes, and it is one of the best ways to create continuous nanomaterials with variable biological, chemical, and physical properties. The produced fibers can be utilized in various domains such as wound dressing, drug release, enzyme immobilization, etc. This review examines the biomedical nanofibers/membranes produced by electrospinning techniques to investigate the effects of process parameters (e.g., solution characteristics, applied voltage, and ambient conditions) on nanofiber characteristics (physical, chemical, and mechanical properties). The solution parameters like (i) optimum concentration, (ii) higher molecular weight, and (iii) higher conductivity produce uniform nanofibers, smoother nanofibers, and a smaller and more uniform fiber diameter, respectively. In addition, process parameters such as (i) higher voltage and (ii) slower flow rate produce more polymer ejection from the nozzle and enhance the smoother fiber production, respectively. The optimum tip-to-collector distance is considered to be 13–15 cm. The ambient conditions such as (i) higher humidity and (ii) higher temperature produce thicker and thinner nanofibers, respectively. The controlled parameters through optimization process determine the size and quality of the fibers. The effects of each parameter are discussed in this review. The applications of nanofibers are also discussed. [ABSTRACT FROM AUTHOR]

Identifying and demarcating watershed areas provides a basis for designing and planning for water resources. In this study, DEMs-based estimates of watershed characteristics of three rivers of Bangladesh - Halda, Sangu, and Chengi - were derived using eight Digital Elevation Models (DEMs) of 30 m, 90 m, and 225 m resolution in the Soil and Water Assessment Tool (SWAT). We have assessed watershed characteristics concerning DEMs, resolutions, and Area Threshold Values (ATVs). Though the elevation data differed, high correlation values among DEMs and resolutions confirm the negligible effect of elevation in the watershed delineation. However, the slope and watershed delineation vary for different DEMs and resolutions. The 90 m DEMs estimated larger areas for Halda and Chengi and lower perimeter values for all three rivers. In watershed delineation, the area near the mouth and flat terrain did not coincide with DEMs. The common intersected area by DEMs can be used as the focal area of watershed management. ATV - 40 km2 significantly influences sub-basin counts and stream network extraction for these watershed areas. Though watershed size and shape were independent of the different ATVs, the DEM-based watershed delineation process in SWAT needs optimum ATV values to represent the stream network precisely. [ABSTRACT FROM AUTHOR]

An experimental study combined with a mathematical modeling of vacuum drying of cocoa beans was carried out to enhance the drying kinetics without compromising the quality of dried products. Experiments were conducted to compare the effects of variation of temperature and pressure on the drying process. The temperature was varied between 40 and 60 °C, while the pressure between 735 and 245 mmHg. The experimental study investigated and analyzed the effects of various process parameters on drying kinetics and quality (in terms of color and pH value). Results demonstrated that the cocoa beans dried at 50 °C temperature and 735 mmHg pressure had the highest drying kinetics, lowest acidity, and best color among all the temperature and pressure values. Compared to convective drying conducted at 60 °C temperature and atmospheric pressure (760 mmHg), vacuum oven drying consistently showed better drying performance with a higher quality of dried products. Modeling for vacuum drying kinetics of cocoa beans was performed with semi-theoretical drying kinetic and fuzzy models to verify the experimental results. The graphical representations of the results demonstrated a good fit between the fuzzy model and the experimental data compared with semi-theoretical drying kinetic models. Finally, a suitable model was proposed for optimum drying conditions compared with the fuzzy and drying kinetic models that could play an important role in designing future advanced dryers. [ABSTRACT FROM AUTHOR]

This research article presents an experimental study of the Fresnel coefficients of quartz glass using a linearly polarized diode laser with a wavelength of 660 nm. The magnitude of reflectance and transmittance for various incident angles and polarizations of the laser were computed. The results showed that the reflectance and transmittance remained constant for lower incident angles but varied with polarization for specific angles, following the Fresnel coefficients. The measured reflectance and transmittance for S- and P-polarized laser beams conformed to the Fresnel equation. The values of R c and T c were determined using the analytical form of the Fresnel equation and found to have magnitudes of the order of 1 0 − 3 with both positive and negative signs. • Experimental study of quartz glass Fresnel coefficients using 660nm laser. • The measured reflectance and transmittance conformed to the Fresnel eqns. • The R c and T c have a magnitude of ∼ 1 0 − 3 with positive and negative signs. [ABSTRACT FROM AUTHOR]

This paper presents the formulation, characterization, and in vitro studies of polymer composite material impregnated with naturally derived hydroxyapatite (HA) particulates for biomedical implant applications. Laevistrombus canarium (LC) seashells (SS) were collected, washed and cleaned, sun-dried for 24 h, and ground into powder particulates. The SS particulates of different weight percentages (0, 10, 20, 30, 40, 50 wt%)-loaded high-density polyethylene (HDPE) composites were fabricated by compression molding for comparative in vitro assessment. A temperature-controlled compression molding technique was used with the operating pressure of 2 to 3 bars for particulate retention in the HDPE matrix during molding. The HDPE/LC composite was fabricated and characterized using X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), energy-dispersive X-ray (EDX), differential scanning calorimetry (DSC), and TGA. Mechanical properties such as tensile, compression, flexural, hardness, and also surface roughness were tested as per ASTM standards. Mass degradation and thermal stability of the HDPE/LC composite were evaluated at different temperatures ranging from 10 to 700 °C using thermogravimetric analysis (TGA). The maximum tensile strength was found to be 27 ± 0.5 MPa for 30 wt% HDPE/LC composite. The thermal energy absorbed during endothermic processes was recorded as 71.24 J/g and the peak melting temperature (Tm) was found to be 128.4 °C for the same 30 wt% of HDPE/LC composite specimen. Excellent cell viability was observed during the in vitro biocompatibility study for EtO-sterilized 30 wt% of HDPE/LC composite specimen, except for a report of mild cytotoxicity in the case of higher concentration (50 µL) of the MG-63 cell line. The results demonstrate the potential of the fabricated composite as a suitable biomaterial for medical implant applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • This review focuses on the recent advances in polymer-based hydroxyapatite scaffolds for their properties and applications. • Preparation methods of the polymer-based hydroxyapatite scaffolds. • Effect of process parameters on the properties of the polymer-based hydroxyapatite scaffolds. • Properties of the polymer-based hydroxyapatite scaffolds. • Advantages and disadvantages of the polymer-based hydroxyapatite scaffolds. • Various applications of the polymer-based hydroxyapatite scaffolds. New materials that mimic natural bone properties, matching functional, mechanical, and biological properties have been continuously developed to rehabilitate bone defects. Desirably, 'tissue engineering' has been a multidisciplinary ground that uses the principles of life sciences and engineering for the biological replacements that restore or replace the tissue function or a whole organ. Nevertheless, the bone grafting treatment has numerous restrictions, counting the major hazards of morbidity from the sites where donor bone grafts are removed, the likelihood for an immune rejection or bacterial transport from the donor site (in case of allogeneic grafting), and the inadequate availability of donor bone grafts that can meet the current demands. Since the proper growth of synthetic materials for implantable bones encourages the reconstruction of bone tissues by providing strong structural support without any damages to the interferences of biological tissue. To serve for such behavior, the biodegradable matrices provide temporary scaffolds within which the bone tissues can be regenerated. Typically, the thermoplastic aliphatic polyesters are found to serve this purpose. The great significance of this field lies in the in vitro growth of precise cells on porous matrices (scaffolds) to generate three-dimensional (3D) tissues that can be entrenched into the location of tissue/bone damage. Numerous gifts have been gifted by our nature to advance and preserve the well-being of all living things either directly or indirectly. This review focuses on the recent advances in polymer-based hydroxyapatite scaffolds including their properties and applications. [ABSTRACT FROM AUTHOR]

Objective: Breast cancer is one of the leading cancer causes among women worldwide. It can be classified as invasive ductal carcinoma (IDC) or metastatic cancer. Early detection of breast cancer is challenging due to the lack of early warning signs. Generally, a mammogram is recommended by specialists for screening. Existing approaches are not accurate enough for real-time diagnostic applications and thus require better and smarter cancer diagnostic approaches. This study aims to develop a customized machine-learning framework that will give more accurate predictions for IDC and metastasis cancer classification., Methods: This work proposes a convolutional neural network (CNN) model for classifying IDC and metastatic breast cancer. The study utilized a large-scale dataset of microscopic histopathological images to automatically perceive a hierarchical manner of learning and understanding., Results: It is evident that using machine learning techniques significantly (15%-25%) boost the effectiveness of determining cancer vulnerability, malignancy, and demise. The results demonstrate an excellent performance ensuring an average of 95% accuracy in classifying metastatic cells against benign ones and 89% accuracy was obtained in terms of detecting IDC., Conclusions: The results suggest that the proposed model improves classification accuracy. Therefore, it could be applied effectively in classifying IDC and metastatic cancer in comparison to other state-of-the-art models., (© 2024 The Author(s). Cancer Medicine published by John Wiley & Sons Ltd.)

The emergence and spread of antibiotic-resistant (AR) bacterial strains and biofilm-associated diseases have heightened concerns about exploring alternative bactericidal methods. The WHO estimates that at least 700 000 deaths yearly are attributable to antimicrobial resistance, and that number could increase to 10 million annual deaths by 2050 if appropriate measures are not taken. Therefore, the increasing threat of AR bacteria and biofilm-related infections has created an urgent demand for scientific research to identify novel antimicrobial therapies. Nanomaterials (NMs) have emerged as a promising alternative due to their unique physicochemical properties, and ongoing research holds great promise for developing effective NMs-based treatments for bacterial and viral infections. This review aims to provide an in-depth analysis of NMs based mechanisms combat bacterial infections, particularly those caused by acquired antibiotic resistance. Furthermore, this review examines NMs design features and attributes that can be optimized to enhance their efficacy as antimicrobial agents. In addition, plant-based NMs have emerged as promising alternatives to traditional antibiotics for treating multidrug-resistant bacterial infections due to their reduced toxicity compared to other NMs. The potential of plant mediated NMs for preventing AR is also discussed. Overall, this review emphasizes the importance of understanding the properties and mechanisms of NMs for the development of effective strategies against antibiotic-resistant bacteria., Competing Interests: We confirm that there are no known conflicts of interest associated with this work, and there has been no significant financial support for this work that could have influenced its outcome. Furthermore, we ensure that the manuscript has been read and approved by all named authors and that there are no other persons who satisfied the criteria for authorship but are not listed. We further confirm that we have all approved the authors' order listed in the manuscript. Due care has been taken to ensure the integrity of the work., (This journal is © The Royal Society of Chemistry.)

The exploration of nanocellulose has been aided by rapid nanotechnology and material science breakthroughs, resulting in their emergence as desired biomaterials. Nanocellulose has been thoroughly studied in various disciplines, including renewable energy, electronics, environment, food production, biomedicine, healthcare, and so on. Cellulose nanocrystal (CNC) is a part of the organic crystallization of macromolecular compounds found in bacteria's capsular polysaccharides and plant fibers. Owing to numerous reactive chemical groups on its surface, physical adsorption, surface grating, and chemical vapor deposition can all be used to increase its performance, which is the key reason for its wide range of applications. Cellulose nanocrystals (CNCs) have much potential as suitable matrices and advanced materials, and they have been utilized so far, both in terms of modifying and inventing uses for them. This work reviews CNC's synthesis, properties and various industrial applications. This review has also discussed the widespread applications of CNC as sensor, acoustic insulator, and fire retardant material.

Detecting cancer at an early stage is crucial for timely treatment and better chances of survival. This research focuses on a scanning method for detecting cancer by examining the nonlinear optical characteristics of blood plasma samples. The study used both cancerous and noncancerous plasma samples and presented the results statistically by utilizing an incident laser power-dependent nonlinear optical phase shift variable called ζ in the Z-scan technique. The results showed a clear difference between the cancerous and non-cancerous samples with an accuracy of 92%. Furthermore, the study suggests the potential for measuring the cancer staging from the cancerous plasma. The study also confirmed a significant difference in ζ for plasma samples undergoing chemotherapy. A red laser with high power (above 18mW) was used to avoid the involvement of fluorophores or other chemical reagents in the plasma samples during the measurement.

Many implant materials have been used in various dental applications depending on their efficacy and availability. A dental implant must possess the required characteristics, such as biocompatibility, corrosion & wear resistance, adequate mechanical properties, osseointegration, etc., to ensure its safe and optimum use. This review analyzes various aspects of titanium (Ti) and Ti alloys, including properties, manufacturing processes, surface modifications, applications as dental implants, and limitations. In addition, it also presents a perception of recent advances in Ti-based implant materials and the futuristic development of innovative dental implants., Competing Interests: The authors declare no conflict of interest., (© 2022 The Authors.)

Increasingly prevalent respiratory infectious diseases (e.g., COVID-19) have posed severe threats to public health. Viruses including coronavirus, influenza, and so on can cause respiratory infections. A pandemic may potentially emerge owing to the worldwide spread of the virus through persistent human-to-human transmission. However, transmission pathways may vary; respiratory droplets or airborne virus-carrying particles can have a key role in transmitting infections to humans. In conjunction with social distancing, hand cleanliness, and other preventative measures, the use of face masks is considered to be another scientific approach to combat ubiquitous coronavirus. Different types of face masks are produced using a range of materials (e.g., polypropylene, polyacrylonitrile, polycarbonate, polyurethane, polystyrene, polyester and polyethylene) and manufacturing techniques (woven, knitted, and non-woven) that provide different levels of protection to the users. However, the efficacy and proper disposal/management of the used face masks, particularly the ones made of non-biodegradable polymers, pose great environmental concerns. This review compiles the recent advancements of face masks, covering their requirements, materials and techniques used, efficacy, challenges, risks, and sustainability towards further enhancement of the quality and performance of face masks.

In this work, heterostructure SnO 2 /ZnO nanocomposite photocatalyst was prepared by a straightforward one step polyol method. The resulting photocatalysts were characterized by X-ray diffraction (XRD), nitrogen adsorption-desorption analyses, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and UV-vis diffuse reflectance spectroscopy (UV-vis DRS). The results showed that the synthesized SnO 2 /ZnO nanocomposites possessed mesoporous wurtzite ZnO and cassiterite SnO 2 nanocrystallites. The photocatalytic activity of the prepared SnO 2 /ZnO photocatalyst was investigated by the degradation of methylene blue dye under UV light irradiation. The heterostructure SnO 2 /ZnO photocatalyst showed much higher photocatalytic activities for the degradation of methylene blue dye than individual SnO 2 , ZnO nanomaterials and reference commercial TiO 2 P25. This higher photocatalytic degradation activity was due to enhanced charge separation and subsequently the suppression of charge recombination in the SnO 2 /ZnO photocatalyst resulting from band offsets between SnO 2 and ZnO. Finally, these heterostructure SnO 2 /ZnO nanocatalysts were stable and could be recycled several times without any appreciable change in degradation rate constant which opens new avenues toward potential industrial applications., Competing Interests: On behalf of all authors, the corresponding author declares that there is no conflict of interest., (This journal is © The Royal Society of Chemistry.)

We examined the potential for ultrasound as a noninvasive tool for maturation monitoring in Atlantic salmon (Salmo salar) males. Ultrasound examination and measurements were compared to common practices for maturation monitoring such as gonadosomatic index (GSI), sex hormone analysis, and histological analysis of spermatogenesis. There were significant correlations (R 2  = 0.68, P < 0.01) between ultrasound-based measurements of the left testis and total testes weight and GSI, and ultrasound could be used for noninvasive GSI measurements. Echogenicity of ultrasound images corresponded to the histological stages observed, which added nuance to ultrasound-based GSI measurements during final weeks preceding stripping. We propose that ultrasound can be used as an alternative to more invasive methods for sexual maturation monitoring in wild and farmed Atlantic salmon males. Using ultrasound technology, we have established a quick and noninvasive method that could reduce the number of stressful handlings and unwanted sacrifice of broodfish required for maturation monitoring in Atlantic salmon males., (© 2019 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.)

Skeletal involvement in chronic kidney disease manifests long before the initiation of dialysis. This study aimed at identifying the extent of renal bone disease among predialysis and on maintenance dialysis patients. Thirty-two patients (Group 1) on maintenance hemodialysis (MHD) for a variable period of time were compared with 20 newly detected irregularly treated advanced renal failure (immediately predialysis), patients (Group 2) for their clinical, biochemical and imaging features. The mean age of Group 1 and Group 2 patients was 45+/-14 vs. 34+/-15 years (p<0.05). Comparison of blood biochemistries between Groups 1 and 2 showed serum creatinine 9.9+/-2.9 vs. 13.4+/-4.4 mg/dL (p<0.01); calcium 10.1+/-1.8 vs. 7.8+/-1.2 mg/dL (p<0.001); phosphate 4.4+/-1.2 vs. 7.9+/-2.1 mg/dL (p<0.001); alkaline phosphatase 116.4+/-31.7 vs. 85.7+/-30.6 IU/L (p<0.05); and parathormone 71.7+/-48.2 vs. 146.9+/-92.1 pg/mL (p<0.05). Radiological changes present in the 2 groups were as follows: osteopenia 63% vs. 65% (ns); trabecular resorption 53% vs. 20% (p<0.05); soft tissue calcification 31% vs. 10% (p<0.05); bone cysts 16% vs. 26% (ns); and subperiosteal bone resorption 16% vs. 20% (ns). Technetium 99 methylene diphosphonate (Tc-99 MDP) bone scans in both groups of patients showed similar increased uptake in wrist joint, tibia-fibula, costochondral junction, vertebral column, sternum, radius-ulna and mandible. X-ray findings were positive for bone involvement in 59% of cases, and Tc-99 scan was positive in 80% (p<0.05). It is concluded that newly detected, irregularly treated patients with advanced renal failure who are predialysis may present with deranged calcium homeostasis and a high prevalence of bone involvement similar to MHD patients.