Search

The contamination of the environment with heavy metals due to industrial and human activities has become a major concern, posing significant health risks. In this paper, a facile and environmentally sustainable synthesis method is employed to prepare nitrogen-doped carbon dots (NCDs) and used as efficient fluorescent probe for the detection of dual heavy metals including Fe(III) and Hg(II) in real samples. Further, the metal-ion sensing is also validated by electrochemical Cyclic voltammetry (C-V) measurements. Various characterization techniques, including Transmission Electron Microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and Fourier-transform infrared spectroscopy, were employed and confirmed the formation of 2–3 nm N-doped carbon quantum dots with spherical morphology and various surface functional groups. Under irradiation with 440 nm visible light, the synthesized NCDs demonstrated narrow and intense green fluorescence. Leveraging the hydrophilic optical properties, the NCDs were utilized for the detection of Fe(III) and Hg(II) ions in an aqueous environment. The fluorescence of the NCDs was found to be quenched in the presence of Fe(III) and Hg(II), and the quenching rate showed a linear correlation with the concentration of the metal ions. The limit of detection (LOD) for Fe(III) and Hg(II) ions was determined using the Stern-Volmer relationship, resulting in LOD values of 35.8 nM and 6.8 nM respectively. The fluorescence quenching is attributed to the electron transfer between NCDs to Fe(III) and Hg(II) ions, Further, the high sensitivity and selectivity of NCDs for Hg(II) was observed by fluorometric sensing and electrochemical measurements. Real water sample analysis in pond water, sea water and well water without any pretreatment showed 90–100% recovery. Above mentioned findings lay the foundation for the potential application of prepared NCDs as fluorescence sensors in aqueous media, offering a promising avenue for future development in this field.

Graphical abstract:

XRD pattern of 0.38Ba(Cu1/3Nb2/3)O3–0.62PbTiO3ceramic for varying MnO2additive content. Inset—Zoom view of XRD pattern for illustration of (200) reflection.

Variation of d 33with varying MnO2additive content for 0.38Ba(Cu1/3Nb2/3)O3–0.62PbTiO3ceramic.

P–Ehysteresis loop of 0.38Ba(Cu1/3Nb2/3)O3–0.62PbTiO3ceramic for varying MnO2additive content.

The control of antibiotic resistance is at an alarming stage, making the detection of antibiotics as utmost importantance. A sono-chemically-synthesized reduced-graphene oxide-yttrium oxide nanocomposite (rGO@Y2O3NC) was used to develop an effective electrochemical immunosensing platform for gentamicin detection. The rGO@Y2O3NC was characterized using different techniques, providing insights into its structural and functional properties. The detection was carried out on a carbon screen printed electrode modified with rGO@Y2O3NC using differential pulse voltammetry technique. The rGO@Y2O3NC helped to enhance the electrochemical activity and the functional groups present on rGO helped in efficient electrostatic immobilization of the antibody. Protein kinase A triggered the immunologic interaction and hence helped in achieving higher sensitivity. The developed immunosensor exhibited an impressive limit of detection of 0.457 pM, with a wide range of detection from 1 pM to 100 μM with a sensitivity of 7.03 μA pM−1cm−2, representing a substantial enhancement over current technologies. Furthermore, the immunosensor demonstrated practical applicability by effective performance in spiked milk and tap water samples. This highlights its potential for real-world applications in monitoring antibiotic use and ensuring water and food quality control according to regulations.

This study proposes a novel IoT model, the Smart Auto IoT-based Geo-Spatial Rover (Auto-GeRo), which integrates a multi-sensor fusion approach for detection of road anomalies in real-time. The model proposed here utilizes machine learning techniques to achieve a high precision rate of 0.43548 with Random Forest in pothole detection, thereby leading from existing models in both accuracy and cost-effectiveness. The work presented here follows a multi-sensor fusion approach that integrate a motion processing unit (IMU-MPU 9250) sensor with other sensors to capture 3-axial XYZ data for real-time road surface analysis. The primary objective is to identify and detect different road conditions, specifically distinguishing between flat and rough patches. By applying various machine learning algorithms, the research presented here tries to evaluate and optimize the performance of road surface classification based on sensor data collected during the simulation of proposed Auto-GeRo simulation. While Logistic Regression exhibits high accuracy (0.96038), the focus shifts towards precision for effective pothole detection, leading to the selection of the Random Forest model due to its superior precision (0.43548) in identifying roads with potholes. Thus the research highlights the potential of IoT-enabled multi sensor fusion techniques in road transportation network for better road safety and early maintenance thereby reducing the maintenance cost and vehicle damage.

This study explores the crucial aspect of achieving successful welding procedures, where proper heating and fusion of components are essential for creating a unified piece. While TIG welding boasts numerous advantageous features, a notable limitation lies in its lack of penetration. To address this challenge, the authors investigated the efficacy of using non-metallic backing mediums to see the effect of thermal conductivity and specific heat capacity of backing medium on weld penetration in TIG welding processes. By employing these backing mediums, the study aims to shed light on the potential impact of these non-metallic backing mediums on weld quality and penetration depth. This case study focuses on Bead-on-plate TIG welding performed on plates with the same material thickness. In contrast to previous studies that utilized plates as backing mediums (Singh et al. in Sādhanā 46:203, 2021). However, for this case study, water and ice were adopted as alternative backing mediums. The study replicated previous experimental conditions, facilitating a rapid transfer of heat input to the non-metallic backing medium. Apart from evaluating weld penetration, the research also examined the grain size of TIG welds assisted by the backing medium, comparing it with the grain size obtained in standard TIG welding procedures. The findings shed light on the potential impact of these backing mediums on weld quality and microstructural characteristics, contributing valuable insights to the field of TIG welding.

Reconstruction of post traumatic facial soft tissue defect remains a challenge. The reconstruction of nasal substructures with the locoregional flap is been practiced since the times of Sushruta. But still the quest for ideal reconstructive option is in pipeline. We present a case of posttraumatic nasal alar defect with superiorly based interpolated nasolabial flap. The postoperative outcomes were very encouraging.

In the N0 neck the incidence of ECS might range from 13 to 60%. In this retrospective study we intended at evaluating the primary tumor and nodal characteristics that might influence the presence of ECS in early stage OSCC.

In the current period, there is a high demand for the production of liquid fuel which is used for transport purposes all over the world. Therefore, the conversion of methane to methanol fuel is reported as an alternative option for natural gas. Some approaches such as the two-step syngas process, direct single step, and bacterial agent catalyzed reaction use steam reform of methane, methane oxidation processes (via methane selectivity), and methane gaseous form (via methane monooxygenase enzymes) respectively to produce methanol fuel from methane. Also, chemical routes have applied high temperature/pressure catalytic conversion of syngas to methanol. Most conventional approaches discussed are gas to liquid technologies that exploit and monetize nontraditional methanol sources. The utility of methanol as liquid fuel is discussed and now researchers have invented the greatest potential of methanol as a robust product that is produced or synthesized by using a commercial scale conversion process from methane. Normal conversion for methane to methanol via chemical routes is exploited by high temperature and pressure as an energy-intensive process. However, the biological modes of conversion of methane to methanol occur by using methanotrophic bacteria, exhibiting desired transformation capacity at ambient conditions via methane monooxygenase enzyme. Biotechnological modes of conversion have shown the potentiality for their application in an industrially relevant process in eco-friendly ways. Some approaches of biotechnological modes of conversion of methane to methanol by whole-cell, wild-type, and methanotroph cultures are discussed along with many chemical route approaches. In this paper, the authors emphasize the different chemical and biological approaches for methane to methanol conversion with their limitations and applications.

Corynebacterium striatumis considered to be notoriously associated with multidrug resistant nosocomial infections with high mortality. This article encases an unusual case of C. striatumassociated postoperative surgical site infection in post-operative case of oral submucous fibrosis. The prognosis depends majorly on meticulous debridement and regular dressing with concomitant anti-microbials. Patient factors such as immunodeficiency and debilitating comorbidities contribute equally to final outcome.

Graphical Abstract:

NiTi wire of 1 mm diameter was deposited on austenitic stainless steel (304L) for surface property modification using the tungsten inert gas (TIG) cladding process. The study shows that the microstructure and mechanical properties of the NiTi cladding are governed by TIG process parameters, namely TIG current. The micro-hardness of the NiTi clad region has improved 4.7 times compared to the substrate material 304L. The wear resistance of the clad layer against the abrasive disc (Al2O3) shows up to 6 times improvement than the substrate material austenitic stainless steel 304L. The presence of Ti-rich (Ni,Fe)Ti, NiTiFeCr and intermetallics, responsible for high hardness and high wear resistance, has been observed in the clad surface, which have been confirmed by the XRD and EDS analysis. The optical and FESEM micrographs of the clad, intermediate and substrate metals have been analysed, and the influence of TIG current on microstructure and mechanical properties has been investigated. With the improved significant results, NiTi clad specimens can be used as a cutting and grinding tool for industrial applications.

A nutritious diet is required to live a healthy and disease free life and to maintain it information about the biochemical and elemental composition of the diet is very crucial. For this, such techniques are required that have the potential of rapid characterization of biochemical and elements involving simple and easy procedural steps without the involvement of highly trained manpower. Therefore, the study aims to realize the potential of direct current arc optical emission spectroscopy as a digestion/extraction free, rapid and simultaneous multi-elemental detection tool to investigate the elemental composition of the staple food; semolina. The emission spectrum of the semolina has been recorded in the spectral region 350–900 nm by exciting the sample with the help of direct current source. The acquired spectrum shows persistent lines of the calcium, potassium, magnesium, manganese, iron, copper, sodium and chromium. The detected elemental profile of the semolina with direct current arc optical emission spectroscopy can add to the existing knowledge of nutrients in food.

The concept of converting seawater into fresh drinking water should also be applied, which is feasible with the aid of the “Solar Still.” It is eco-friendly and cost-effective, but is not common due to its lower performance. Enormous research work is being conducted to increase the quality of the “Solar Still.” Various methods and their productivity are explored here, which are followed by researchers around the world. The most commonly employed methods used by researchers is focused on Phase Change Material and Energy Storage Material, which would generate distillate during the day. The specification of Phase Shift Materials and Energy Storage Materials is based on thermal conductivity. The cooling of the exterior surface of the glass cover provides a strong temperature differential between the glass cover and the water, which improves the rate of evaporation and condensation and decreases the environmental impact by creating a thin layer above the surface.

Frontal bone is fractured following high-velocity injuries such as road traffic injuries or assaults. At times, the intervention can get delayed to avoid grave intracranial injuries resulting in malunion of the fracture which may later become an aesthetic concern to the patient. Many alloplastic materials and autogenous grafts can be used to reconstruct the defect to replace lost and damaged anatomical bone structures, to renew their original function, and at the same time, to restore the aesthetics. We opted to go for an autogenous graft secured with a titanium mesh which gave us a better outcome.

Lymphomas are solid cohesive neoplasm, originating from the cells of immune system, having diverse presentation. NHL is the third most common group of malignant tumors. Incidence of NHL in extra-nodal sites is approximately 20–30%. Diffuse large B cell Non-hodgkin’s lymphoma (DLBCL) is the most common histological variant of lymphoma. This report discusses a case of Non-Hodgkin’s lymphoma in an 80-year male patient with clinical presentation of non-healing painless ulceroproliferative growth, which mimics squamous cell carcinoma.

The concepts of λ-measures and signed λ-measures (nonadditive measures) defined on effect algebras are introduced and investigated in this paper. A few examples of λ-measures and signed λ-measures are also given. Moreover, the Jordan decomposition theorem for signed λ-measures defined on effect algebras is also presented.

Orbital reconstruction is very challenging due to complex anatomy of the orbit and desirable functional and aesthetic results. Timing of intervention, indications for open reduction, choice of implant material, and placement play a very crucial role in the treatment protocol. Correction of posttraumatic enophthalmos and residual diplopia remain difficult to achieve and even sometimes need secondary revision. In the present case, we have discussed about the correction of posttraumatic enophthalmos and the challenges faced during and postsurgery and review about the management protocol for orbital reconstruction.

Ectopic pleomorphic adenoma is a rare presentation in sites other than major and minor salivary glands. In literature, cases of pleomorphic adenoma in the soft tissue of the neck, skin of the external auditory canal, subcutaneous layer of nose, and lymph node of mediastinum have been reported. We report a case of ectopic pleomorphic adenoma localized in the soft tissue over the anterior border of the ramus of left side of the mandible.

Fructooligosaccharides (FOS) are essential components found in various vegetal biomass sources, including foods, agricultural residues, fruits, and vegetable waste. Comprising 3 to 10 monosaccharide units, they resist digestion in the human gastrointestinal tract and are recognized as prebiotics, fostering the proliferation of beneficial bacteria in the colon. Fructooligosaccharides (FOS), galactooligosaccharides (GOS), xylooligosaccharides (XOS), arabinooligosaccharides (AOS), pectin-derived acidic oligosaccharides (pAOS), cyclodextrins (CD), and others are among the most prevalent oligosaccharides. Probiotics, live microorganisms offering various health benefits upon consumption or application, are commonly found in fermented foods, dietary supplements, and beauty products. Postbiotics, organic residues remaining in the gut after the digestion of prebiotics and probiotics, include substances such as vitamins B and K, amino acids, and antimicrobial peptides that inhibit the growth of harmful bacteria. Pre-, pro-, and postbiotics collectively contribute to a wide array of health advantages, including enhanced immune function, improved gut health, and overall well-being. Agro-residues, fruit, and vegetable waste serve as promising sources of prebiotics, promoting the growth of probiotic bacteria and yielding bioactive compounds like fiber upon consumption. This paper explores sustainable methods for producing oligosaccharides from lignocellulosic biomass, vegetable, and fruit biomass, elucidating their roles in the development of pre-, pro-, and postbiotics for gut health.

Adenoid cystic carcinoma (ACC) is an unusual salivary gland malignancy that remains poorly understood. It is a slow growing but aggressive neoplasm with a tendency for recurrence. It is characterized by the proliferation of ductal (luminal) and myoepithelial cells in cribriform, tubular, solid, and cystic forms. Standard treatment, including surgery with postoperative radiation therapy, has attained reasonable local control rates, but distant metastases do not allow any improvement in the survival rate. The understanding of the molecular mechanisms driving ACC is quite rudimentary. We present a case of a 55-year-old female diagnosed with ACC involving the floor of the mouth with an aim to present the carcinoma's behavior, immunohistocytochemistry, the staining pattern, its treatment, and prognosis.

A strategy has been demonstrated to design a biluminescent security ink using Eu(TTA)3Phen (ETP) and fluorescein for protecting the currency and other essential documents, viz., passport, bank check, certificates, etc. against counterfeiting. The biluminescent security ink exhibits strong red and green emission under 367 and 445 nm excitations, respectively. As it is quite challenging to prepare a material that possesses two prominent (green and red) and distinguishable colors upon excitation with two separate light-emitting diode (LED) sources, emitting at different wavelengths, the biluminescent security ink would be hard to counterfeit as compared with the existing luminescent security ink that exhibits single color under UV light exposure. To check its feasibility for security application, the patterns printed out using the biluminescent security ink were kept under a hot and humid atmosphere for 150 days. Also, the ETP and fluorescein fluorophores were exposed to UV light for a prolonged time, which do not show any sign of deterioration in their luminescence intensities. Furthermore, to check their chemical stability, printed patterns were also exposed to chemicals that have potential to wipe out ink, viz., detergent, ethanol, acetone, and sodium hypochlorite (bleach) solution, and it was noticed that it is well stable against these chemicals. Because of the reasons mentioned above and easy availability of 367 and 445 nm LEDs at low cost, authors believe that the application of this biluminescent security ink can trigger the realization of the full potential of this advanced security feature in detecting fake currency.

Apatite‐type lanthanum silicate (La10Si6O27; LS) nanopowders are synthesized using a hydrothermal process and used for the electrolyte applications in solid oxide fuel cells (SOFCs). The synthesized nanopowders are characterized by Rietveld refinement of the X‐ray diffraction (XRD) data, SEM–energy‐dispersive X‐ray spectroscopy (EDS), TEM, and dialotometry. The prepared nanopowders can be sintered to near theoretical density at sintering temperature of 1500 °C. Reactivity studies between the synthesized La10Si6O27material and cathode materials such as La0.6Sr0.4Co0.2Fe0.8O3−δ(LSCF), Nd2NiO4(NNO), and Pr2NiO4(PNO), are carried out by XRD analysis revealing that they do not react. Symmetric cells are fabricated and characterized electrochemically. The area specific resistances for LSCF, NNO, PNO, and PNO‐LS (1:1 (wt %)) measured at 900 οC, are 100, 2.2, 1.8, and 0.5 Ω cm2, respectively. EDS analysis shows that interdiffusion of cations at the cathode–electrolyte interface is not detected for LS/PNO, which is attributed to the low area‐specific resistance values. The results demonstrate that Pr2NiO4and the composites are promising cathode materials for the apatite‐type lanthanum silicate electrolyte for SOFC applications. Phase‐pure La10Si6O27(LS) ceramicsare synthesized using a hydrothermal process. La10Si6O27could be sintered to 95 % of the theoretical density and the reactivity of LS with several state‐of‐the‐art cathode materials is investigated. Diffusion of cations is not detected at cathode‐electrolyte interface of PNO/LS. Pr2NiO4(PNO), and LS‐PNO are shown to be promising cathodes for LS electrolytes.

•Implementation of the EMD Denoising Speech Enhancement method to enhance single-channel speech signals under various face mask conditions.•Effective utilization of the Fast Fourier Transform (FFT) on the intrinsic mode functions (IMFs) to differentiate between noise and signal during the speech enhancement process.•Validation of the effectiveness of the EMD denoising speech enhancement method through comparison mean opinion scores (CMOS) with a panel of 30 listeners, providing subjective evaluations of the enhanced speech quality.

Bead-on-plate (BOP) welding was carried out using an autogenous tungsten inert gas (TIG) welding to weld P91 steel plates of dimension 100mm×50mm×6mm thick. P91, is generally subjected to post-weld heat treatment (PWHT) to improve the mechanical properties. PWHT has to be carried out within a narrow window of parameters, else, the mechanical properties deteriorate. To overcome this difficulty of maintaining a narrow range of parameters to perform PWHT, in the present study, welded samples were insulated as soon as welding was over by utilizing High-Temperature Rigid Ceramic Fiber Board (HTRCFB). The results of this study were compared with the result of the same material welded by normal TIG welding in an earlier study. This study found that, weld bead geometry, microstructure of the heat insulated TIG welding was higher compared to those of a normal TIG welding. The hardness of heat insulted welding, however decreased marginally over the normal TIG welded samples.

The Bi3+/Yb3+-codoped gadolinium tungstate phosphor has been synthesized through a solid-state reaction method. The structural characterization reveals the crystalline nature of the phosphor. The Bi3+-doped phosphor emits visible radiation from the blue to red regions upon excitation with 330 and 355 nm. The addition of Yb3+to the Bi3+-doped phosphor reduces the emission intensity in the visible region and emits an intense near-infrared (NIR) photon centered at 976 nm through a quantum-cutting (QC) phenomenon. This is due to cooperative energy transfer (CET) from the 3P1level of Bi3+to the 2F5/2level of Yb3+. The presence of Li+ions in the Bi3+/Yb3+-codoped phosphor enhances the emission intensity in the NIR region up to by 3 times, whereas the emission intensity in the visible region is significantly reduced. The energy transfer (ET) from the Bi3+ions to the Yb3+ions is confirmed by lifetime measurements, and the lifetime for the 3P1level of Bi3+decreases continuously with increasing Yb3+concentration. The ET efficiency (ηETE) and corresponding QC efficiency (ηQE) are calculated and found to be 29% and 129%, respectively. The presence of Li+enhances the QC efficiency of the phosphor up to 43%. Thus, the Bi3+/Yb3+/Li+-codoped phosphor is a promising candidate to enhance the efficiency of a crystalline-silicon-based solar cell through spectral conversion.

Background: For many years, various drugs have been used for the treatment of infectious diseases but some bacterial microorganisms have induced resistance to several drugs. In a search of new antimicrobial agents, a series of new steroidal hydrazones were designed and synthesized. Result: The structures of the compounds were established based on the spectral data. The in vitro antimicrobial activity of some newly synthesized compounds against bacteria and fungi was studied. Conclusion: New compounds showed better or similar antimicrobial activity. Designing more efficient steroidal hydrazones from ketosteroid based on the current study may successfully lead to the development of antimicrobial agent. Graphical abstract:

The bulk and nanocrystalline samples of half doped, rare earth, perovskite manganites, Ln0.5Ca0.5MnO3(Ln = La, Nd, Pr) were investigated by X-ray diffraction and magnetic measurements at various temperatures to understand the origin of suppression of charge ordering transitions in nanocrystalline samples of these manganites. The controversial reports regarding the effect of crystallite size reduction on the unit cell volume has been resolved by studying these three manganites prepared by combustion synthesis method. As reported by earlier authors, reduction of the particle size to nanocrystalline range leads to suppression of charge ordering transition and stabilization of ferromagnetic phase at low temperatures. The unit cell volume is found to systematically increase for all the three manganites with decreasing particle size, which results in increased bandwidth and is responsible for suppression of charge ordering transition. Even through the crystal structure of both bulk and nanocrystalline samples is orthorhombic with space group Pnma, crystallite size reduction into nanocrystalline form affects the orthorhombic strain, lattice parameter, atomic coordinates, and unit cell volume. A comparative study for the La0.5Ca0.5MnO3samples prepared by sol–gel route is also presented to show that the reduction of the unit cell volume with decreasing crystallite size is linked with nonstoichiometry of the samples, which can also lead to the suppression of the charge ordering transition and stabilization of ferromagnetic state in nanocrystalline form reported by some earlier authors. The role of inherent anisotropic strain in nanocrystalline samples on the magnetic state and phase transitions is also investigated.

We synthesized the Eu(TTA)3Phen complex and present herein a detailed study of its photophysics. The investigations encompass samples dispersed in poly(vinyl alcohol) and in ethanol in order to explore the versatile applicability of these lanthanide-based materials. Details upon the interaction between Eu, TTA, and the Phen ligands are revealed by Fourier transform infrared and UV–visible absorption, complemented by steady state and temporally resolved emission studies, which provide evidence of an efficient energy transfer from the organic ligands to the central Eu3+ion. The material produces efficient emission even under sunlight exposure, a feature pointing toward suitability for luminescent solar concentrators and UV light sensing, which is demonstrated for intensities as low as 200 nW/cm2. The paper further promotes the complex’s capability to be used as luminescence-based temperature sensor demonstrated by the considerable emission intensity changes of ∼4.0% per K in the temperature range of 50–305 K and ∼7% per K in the temeperature range 305–340 K. Finally, increasing the optical excitation causes both spontaneous emission amplification and emission peak narrowing in the Eu(TTA)3Phen complex dispersed in poly(vinyl alcohol) - features indicative of stimulated emission. These findings in conjunction with the fairly large stimulated emission cross-section of 4.29 × 10–20cm2demonstrate that the Eu(TTA)3Phen complex dispersed in poly(vinyl alcohol) could be a very promising material choice for lanthanide-polymer based laser architectures.