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1.
ACS Biomater Sci Eng ; 10(3): 1403-1417, 2024 03 11.
Article in English | MEDLINE | ID: mdl-38308598

ABSTRACT

Assessing blood compatibility is crucial before in vivo procedures and is considered more reliable than many in vitro tests. This study examines the physiochemical properties and blood compatibility of bioactive powders ((0.5-2 wt % carbon nanotube (CNT)/alumina)-20 wt %)) produced through a heterocoagulation colloidal technique followed by ball milling with hydroxyapatite (HAp). The 1 wt % CNT composite demonstrated a surface charge ∼5 times higher than HAp at pH 7.4, with a value of -11 mV compared to -2 mV. This increase in electrostatic charge is desirable for achieving hemocompatibility, as evidenced by a range of blood compatibility assessments, including hemolysis, blood clotting, platelet adhesion, platelet activation, and coagulation assays (prothrombin time (PT) and activated partial thrombin time (aPTT)). The 1 wt % CNT composite exhibited hemolysis ranging from 2 to 7%, indicating its hemocompatibility. In the blood clot investigation, the absorbance values for 1-2 wt % CNT samples were 0.927 ± 0.038 and 1.184 ± 0.128, respectively, indicating their nonthrombogenicity. Additionally, the percentage of platelet adhered on the 1 wt % CNT sample (∼5.67%) showed a ∼2.5-fold decrement compared to the clinically used negative control, polypropylene (∼13.73%). The PT and aPTT experiments showed no difference in the coagulation time for CNT samples even at higher concentrations, unlike HAC2 (80 mg). In conclusion, the 1 wt % CNT sample was nontoxic to human blood, making it more hemocompatible, nonhemolytic, and nonthrombogenic than other samples. This reliable study reduces the need for additional in vitro and in vivo studies before clinical trials, saving time and cost.


Subject(s)
Durapatite , Nanotubes, Carbon , Humans , Durapatite/chemistry , Durapatite/pharmacology , Nanotubes, Carbon/toxicity , Nanotubes, Carbon/chemistry , Hemolysis , Blood Platelets , Platelet Adhesiveness
2.
Biomater Adv ; 158: 213791, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38295645

ABSTRACT

Orthopedic implants made from titanium are a popular choice in the medical field because of their remarkable strength-to-weight ratio. Nevertheless, they may not interact well with human blood, resulting in thrombosis and hemolysis. In fact, non-hemocompatibility is believed to be responsible for about 31 % of medical device failures in the US alone, requiring painful and expensive revision surgery. To address this issue, bioactive hydroxyapatite coatings are applied to Ti-6Al-4V implants using thermal spray techniques. However, the temperature used during thermal processing impacts the coating's surface properties, affecting the mechanical and biological properties. Furthermore, the effectiveness of HA coatings on titanium for orthopedic applications has not been validated by biocompatibility tests, particularly hemocompatibility. In this study, we aimed to investigate the relative efficacy of three thermal spray processes of different temperature ranges: Atmospheric plasma spray (APS) (high temperature), Flame spray (FS) (moderate temperature), and High-Velocity Oxy-Fuel spray (HVOF) (low temperature), and study their impact on coating's surface properties, affecting blood components and implant's strength. The crystallinity of the HA coating increased by 32 % with a decrease in the operating temperature (APS < FS < HVOF). HVOF coating exhibited a ~ 34 % and ~ 120 % improvement in adhesion strength and ~ 31 % and 59 % increment in hardness compared to APS and FS coating, respectively, attributed to its low porosity, low coating thickness (~55 µm), and high degree of crystallinity. The HVOF coating showcased a significant increase in non-hemolytic behavior, with hemolysis rates ~8 and ~ 11 times lower than APS and FS coatings, respectively, owing to its smooth texture and high degree of crystallinity (p < 0.05). Furthermore, the HVOF coating exhibited minimal blood clotting based on the whole blood clotting assay, again confirmed by PT and aPTT assays showing delayed clotting time, indicating its non-thrombogenic behavior. The number of platelets adhered to the three coatings showed no significant difference compared to Ti-6Al-4V. APS and FS coatings showed low platelet activation, unlike HVOF coating and titanium, which revealed round platelets, similar to the negative control. Neither titanium nor HA coatings exhibited antibacterial properties, which may be due to their high affinity for organic substances, which promotes bacterial adhesion and replication. Among the three thermal processes, HVOF coating displayed good apatite growth, non-hemolytic, and non-thrombogenicity with no platelet activation owing to its low processing temperature, high degree of crystallinity (89.7 %), hydrophilicity, smooth (~4 µm) and dense (~97 %) microstructural properties. The results demonstrated that the HVOF-HA coating presented in this work meets the hemocompatible requirements and shows promise for prospective application as an orthopedic implant. Furthermore, this study has the potential to significantly reduce the use of animals in in-vivo research and improve their welfare while also cutting costs.


Subject(s)
Durapatite , Orthopedics , Animals , Humans , Durapatite/pharmacology , Hemolysis , Titanium/pharmacology , Apatites
3.
Small ; 20(1): e2303688, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37670541

ABSTRACT

Metal nanoparticles (MNPs) are synthesized using various techniques on diverse substrates that significantly impact their properties. However, among the substrate materials investigated, the major challenge is the stability of MNPs due to their poor adhesion to the substrate. Herein, it is demonstrated how a newly developed H-glass can concurrently stabilize plasmonic gold nanoislands (GNIs) and offer multifunctional applications. The GNIs on the H-glass are synthesized using a simple yet, robust thermal dewetting process. The H-glass embedded with GNIs demonstrates versatility in its applications, such as i) acting as a room temperature chemiresistive gas sensor (70% response for NO2 gas); ii) serving as substrates for surface-enhanced Raman spectroscopy for the identifications of Nile blue (dye) and picric acid (explosive) analytes down to nanomolar concentrations with enhancement factors of 4.8 × 106 and 6.1 × 105 , respectively; and iii) functioning as a nonlinear optical saturable absorber with a saturation intensity of 18.36 × 1015 W m-2 at 600 nm, and the performance characteristics are on par with those of materials reported in the existing literature. This work establishes a facile strategy to develop advanced materials by depositing metal nanoislands on glass for various functional applications.

4.
ACS Appl Mater Interfaces ; 15(50): 58984-58993, 2023 Dec 20.
Article in English | MEDLINE | ID: mdl-38051915

ABSTRACT

Aluminum hydroxide, an abundant mineral found in nature, exists in four polymorphs: gibbsite, bayerite, nordstrandite, and doyleite. Among these polymorphs gibbsite, bayerite, and commercially synthesized amorphous aluminum hydroxide have been investigated as sorbent materials for lithium extraction from sulfate solutions. The amorphous form of Al(OH)3 exhibits a reactivity higher than that of the naturally occurring crystalline polymorphs in terms of extracting Li+ ions. This study employed high-temperature oxide melt solution calorimetry to explore the energetics of the sorbent polymorphs. The enthalpic stability order was measured to be gibbsite > bayerite > amorphous Al(OH)3. The least stable form, amorphous Al(OH)3, undergoes a spontaneous reaction with lithium, resulting in the formation of a stable layered double hydroxide phase. Consequently, amorphous Al(OH)3 shows promise as a sorbent material for selectively extracting lithium from clay mineral leachate solutions. This research demonstrates the selective direct extraction of Li+ ions using amorphous aluminum hydroxide through a liquid-solid lithiation reaction, followed by acid-free delithiation and relithiation processes, achieving an extraction efficiency of 86%, and the maximum capacity was 37.86 mg·g-1 in a single step during lithiation. With high selectivity during lithiation and nearly complete recoverability of the sorbent material during delithiation, this method presents a circular economy model. Furthermore, a life cycle analysis was conducted to illustrate the environmental advantages of replacing the conventional soda ash-based precipitation process with this method, along with a simple operational cost analysis to evaluate reagent and fuel expenses.

5.
J Phys Chem C Nanomater Interfaces ; 127(36): 17754-17760, 2023 Sep 14.
Article in English | MEDLINE | ID: mdl-37736295

ABSTRACT

This study experimentally explores the energetics for the formation of boron-imidazolate frameworks (BIFs), which are synthesized by mechanochemistry. The topologically similar frameworks employ the same tetratopic linker based on tetrakis(imidazolyl)boric acid but differ in the monovalent cation metal nodes. This permits assessment of the stabilizing effect of metal nodes in frameworks with sodalite (SOD) and diamondoid (dia) topologies. The enthalpy of formation from endmembers (metal oxide and linker), which define thermodynamic stability of the structures, has been determined by use of acid solution calorimetry. The results show that heavier metal atoms in the node promote greater energetic stabilization of denser structures. Overall, in BIFs the relation between cation descriptors (ionic radius and electronegativity) and thermodynamic stability depends on framework topology. Thermodynamic stability increases with the metallic character of the cation employed as the metal node, independent of the framework topology. The results suggest unifying aspects for thermodynamic stabilization across MOF systems.

6.
Luminescence ; 38(9): 1668-1677, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37434298

ABSTRACT

Psoriasis is a noncontagious, long-lasting skin infection that affects many people around the world. Numerous therapeutic artificial treatments are available for the treatment of psoriasis, such as photodynamic therapy using broadband ultraviolet (UV) lamps, which have harmful effects on human skin. Similarly, the natural healing systems such as sunlight have a higher risk of sunburn and can cause dangerous forms of skin cancer. Significant light emission of a specific wavelength (in the UV range), and phosphor-based devices demonstrate the effectiveness of treating psoriasis without damaging the skin. Gd3+ -doped calcium magnesium silicate [Ca2 MgSi2 O7 :Gd3+ ,(CMS:Gd3+ )] phosphor is one of the ideal phosphors that emit specific narrow UV wavelengths for curing psoriasis and is in great demand in the field of dermatology. Photoluminescence analysis at room temperature (~25°C) shows that the synthesized CMS:Gd3+ phosphor emits narrowband UV-B light with a peak intensity at 314 nm. Comparative studies of the standard action spectrum of psoriasis with the emission spectrum of the CMS:Gd3+ phosphor show that the synthesized phosphor was the most suitable material for treating a variety of diseases, including psoriasis, vitiligo, type-1 diabetes, dental disease, sleep and mood disorders, and other skin diseases.


Subject(s)
Psoriasis , Rejuvenation , Humans , Psoriasis/radiotherapy , Ultraviolet Rays , Ions/chemistry
7.
ACS Appl Energy Mater ; 6(6): 3213-3224, 2023 Mar 27.
Article in English | MEDLINE | ID: mdl-37013178

ABSTRACT

The microparticle quality and reproducibility of Li(Ni0.8Co0.1Mn0.1)O2 (NCM811) cathode materials are important for Li-ion battery performance but can be challenging to control directly from synthesis. Here, a scalable reproducible synthesis process is designed based on slug flow to rapidly generate uniform micron-size spherical-shape NCM oxalate precursor microparticles at 25-34 °C. The whole process takes only 10 min, from solution mixing to precursor microparticle generation, without needing aging that typically takes hours. These oxalate precursors are convertible to spherical-shape NCM811 oxide microparticles, through a preliminary design of low heating rates (e.g., 0.1 and 0.8 °C/min) for calcination and lithiation. The outcome oxide cathode particles also demonstrate improved tap density (e.g., 2.4 g mL-1 for NCM811) and good specific capacity (202 mAh g-1 at 0.1 C) in coin cells and reasonably good cycling performance with LiF coating.

8.
Anim Biotechnol ; 34(7): 3174-3186, 2023 Dec.
Article in English | MEDLINE | ID: mdl-35468300

ABSTRACT

The central dogma of molecular biology is responsible for the crucial flow of genetic information from DNA to protein through the transcription and translation process. Although the sequence of DNA is constant in all organs, the difference in protein and variation in the phenotype is mainly due to the quality and quantity of tissue-specific gene expression and methylation pattern. The term methylation has been defined and redefined by various scientists in the last fifty years. There is always huge excitement around this field because the inheritance of something is beyond its DNA sequence. Advanced gene methylation studies have redefined molecular genetics and these tools are considered de novo in alleviating challenges of animal disease and production. Recent emerging evidence has shown that the impact of DNA, RNA, and protein methylation is crucial for embryonic development, cell proliferation, cell differentiation, and phenotype production. Currently, many researchers are focusing their work on methylation to understand its significant role in expression, disease-resistant traits, productivity, and longevity. The main aim of the present review is to provide an overview of DNA, RNA, and protein methylation, current research output from different sources, methodologies, factors responsible for methylation of genes, and future prospects in animal genetics.


Subject(s)
DNA Methylation , DNA , Animals , DNA Methylation/genetics , Phenotype , Genotype , DNA/genetics , RNA/metabolism
9.
ACS Omega ; 7(46): 42482-42488, 2022 Nov 22.
Article in English | MEDLINE | ID: mdl-36440143

ABSTRACT

Due to higher packing density, lower working potential, and area specific impedance, the MLi2Ti6O14 (M = 2Na, Sr, Ba, and Pb) titanate family is a potential alternative to zero-strain Li4Ti5O12 anodes used commercially in Li-ion batteries. However, the exact lithiation mechanism in these compounds remains unclear. Despite its structural similarity, MLi2Ti6O14 behaves differently depending on charge and size of the metal ion, hosting 1.3, 2.7, 2.9, and 4.4 Li per formula unit, giving charge capacity values from 60 to 160 mAh/g in contrast to the theoretical capacity trend. However, high-temperature oxide melt solution calorimetry measurements confirm strong correlation between thermodynamic stability and the observed capacity. The main factors controlling energetics are strong acid-base interactions between basic oxides MO, Li2O and acidic TiO2, size of the cation, and compressive strain. Accordingly, the energetic stability diminishes in the order Na2Li2Ti6O14 > BaLi2Ti6O14 > SrLi2Ti6O14 > PbLi2Ti6O14. This sequence is similar to that in many other oxide systems. This work exhibits that thermodynamic systematics can serve as guidelines for the choice of composition for building better batteries.

10.
Dalton Trans ; 51(29): 11169-11179, 2022 Jul 26.
Article in English | MEDLINE | ID: mdl-35801572

ABSTRACT

Mineral exploration forms a key approach for unveiling functional battery electrode materials. The synthetic preparation of naturally found minerals and their derivatives can aid in designing of new electrodes. Herein, saranchinaite Na2Cu(SO4)2 and its hydrated derivative kröhnkite Na2Cu(SO4)2·2H2O bisulfate minerals have been prepared using a facile spray drying route for the first time. The phase stability relation during the (de)hydration process was examined synergising in situ X-ray diffraction and thermochemical studies. Kröhnkite forms the thermodynamically stable phase as the hydration of saranchinaite to kröhnkite is highly exothermic (-51.51 ± 0.63 kJ mol-1). Structurally, kröhnkite offers a facile 2D pathway for Na+ ion migration resulting in 20 times higher total conductivity than saranchinaite at 60 °C. Both compounds exhibited a conversion redox mechanism for Li-ion storage with the first discharge capacity exceeding 650 mA h g-1 (at 2 mA g-1vs. Li+/Li) upon discharge up to 0.05 V. Post-mortem analysis revealed that the presence of metallic Cu in the discharged state is responsible for high irreversibility during galvanostatic cycling. This study reaffirms the exploration of Cu-based polyanionic sulfates, which while having limited (de)insertion properties, can be harnessed for conversion-based electrode materials for batteries.

11.
Inorg Chem ; 61(27): 10342-10358, 2022 Jul 11.
Article in English | MEDLINE | ID: mdl-35759456

ABSTRACT

The presence of lanthanide-tellurite "anti-glass" nanocrystalline phases not only affects the transparency in glass-ceramics (GCs) but also influences the emission of a dopant ion. Therefore, a methodical understanding of the crystal growth mechanism and local site symmetry of doped luminescent ions when embedded into the precipitated "anti-glass" phase is crucial, which unfolds the practical applications of GCs. Here, we examined the Ln2Te6O15 "anti-glass" nanocrystalline phase growth mechanism and local site symmetry of Eu3+ ions in transparent GCs produced from 80TeO2-10TiO2-(5 - x)La2O3-5Gd2O3-xEu2O3 glasses, where x = 0, 1, 2. A crystallization kinetics study identifies a unique crystal growth mechanism via a constrained nucleation rate. The extent of "anti-glass" phase precipitation and its growth in GCs with respect to heat-treatment duration is demonstrated using X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM) analysis. Qualitative analysis of XRD confirms the precipitation of both La2Te6O15 and Gd2Te6O15 nanocrystalline phases. Rietveld refinement of powder X-ray diffraction patterns reveals that Eu3+ ions occupy "Gd" sites in Gd2Te6O15 over "La" sites in La2Te6O15. Raman spectroscopy reveals the conversion of TeO3 units to TeO4 units with Eu2O3 addition. This confirms the polymerizing role of Eu2O3 and consequently high crystallization tenacity with increasing Eu2O3 concentration. The measured Eu3+ ion photoluminescence spectra revealed its local site symmetry. Moreover, the present GCs showed adequate thermal cycling stability (∼50% at 423 K) with the highest activation energy of around 0.3 eV and further suggested that the present transparent GCs would be a potential candidate for the fabrication of red-light-emitting diodes (LEDs) or red component phosphor in W-LEDs.

12.
J Am Chem Soc ; 144(18): 8223-8230, 2022 May 11.
Article in English | MEDLINE | ID: mdl-35482958

ABSTRACT

A recently discovered new family of 3D halide perovskites with the general formula (A)1-x(en)x(Pb)1-0.7x(X)3-0.4x (A = MA, FA; X = Br, I; MA = methylammonium, FA = formamidinium, en = ethylenediammonium) is referred to as "hollow" perovskites owing to extensive Pb and X vacancies created on incorporation of en cations in the 3D network. The "hollow" motif allows fine tuning of optical, electronic, and transport properties and bestowing good environmental stability proportional to en loading. To shed light on the origin of the apparent stability of these materials, we performed detailed thermochemical studies, using room temperature solution calorimetry combined with density functional theory simulations on three different families of "hollow" perovskites namely en/FAPbI3, en/MAPbI3, and en/FAPbBr3. We found that the bromide perovskites are more energetically stable compared to iodide perovskites in the FA-based hollow compounds, as shown by the measured enthalpies of formation and the calculated formation energies. The least stable FAPbI3 gains stability on incorporation of the en cation, whereas FAPbBr3 becomes less stable with en loading. This behavior is attributed to the difference in the 3D cage size in the bromide and iodide perovskites. Configurational entropy, which arises from randomly distributed cation and anion vacancies, plays a significant role in stabilizing these "hollow" perovskite structures despite small differences in their formation enthalpies. With the increased vacancy defect population, we have also examined halide ion migration in the FA-based "hollow" perovskites and found that the migration energy barriers become smaller with the increasing en content.

13.
Front Chem ; 9: 719169, 2021.
Article in English | MEDLINE | ID: mdl-34540800

ABSTRACT

Order-disorder on both cation and oxygen sites is a hallmark of fluorite-derived structures, including pyrochlores. Ordering can occur on long- and short-range scales and can result in persistent metastable states. In various cubic oxide systems, different types of disorder are seen. The purpose of this paper is to review and compare the types and energetics of order-disorder phenomena in several families of cubic oxides having pyrochlore, weberite, defect fluorite, perovskite, rocksalt, and spinel structures. The goal is to better understand how structure, composition, and thermodynamic parameters (enthalpy and entropy) determine the feasibility of different competing ordering processes and structures in these diverse systems.

14.
Phys Chem Chem Phys ; 23(28): 15245-15256, 2021 Jul 21.
Article in English | MEDLINE | ID: mdl-34236065

ABSTRACT

Globally, phosphor converted white-LEDs (W-LEDs) are among the most suitable sources to reduce energy consumption. Nevertheless, modernization of efficient broadband emitting phosphors is most crucial to improve the W-LED performance. Herein, we synthesized a series of novel broadband emitting Sr2-xAl3O6F:xEu2+ phosphors via a new microwave-assisted diffusion method. Rietveld refinement of the obtained X-ray diffraction results was performed to recognize the exact crystal phase and the various cationic sites. Oxygen vacancies (VO) formed under synthetic reducing conditions enabled Sr2Al3O6F to demonstrate bright self-activated bluish emission. Doping of Eu2+ ions unlocked the energy transfer process from the host to the activator ions, owing to which, the self-activated emission diminished and the Eu2+-doped sample showed amplified bluish-green emission. The gradual increase in Eu2+ concentrations regulated the controllable emissions from the bluish (0.34, 0.42) to the greenish (0.38, 0.43) zone under UV excitation. Because of the different absorption preferences of Eu2+ ions located at the different Sr2+ sites, Sr2-xAl3O6F:xEu2+ exhibited bluish-white emission under blue irradiation. A further enhancement in PL intensity had been observed by the cation substitution of Ba2+ for Sr2+ sites in the optimum Sr1.95Al3O6F:0.05Eu2+ phosphor. The as-fabricated W-LEDs utilizing the optimized Sr1.75Ba0.2Al3O6F:0.05Eu2+ phosphor exhibited a cool-white light emission along with a 372 nm NUV-LED and a 420 nm blue-LED with a moderate CRI of 70 and a CCT above 6000 K. Such cool white emission was controlled to natural white with the CCT close to 5000 K, and the CRI above 80 via utilizing a suitable red emitting phosphor. The W-LED performances of the optimized phosphor justified its applicability to produce white light for lighting applications.

15.
Eur J Paediatr Dent ; 22(1): 75-79, 2021.
Article in English | MEDLINE | ID: mdl-33719488

ABSTRACT

AIM: Behaviour management is one of the essential skills of paediatric dentists. Appropriate use of behavioural principles helps the child in developing the skills and behaviours necessary to willingly undergo dental care, not hindered by undue anxiety or fear. However, very little is known about the knowledge of principles regarding behaviour management among paediatric dentists. Contingency management which is based on the principles of behaviour analysis is a widely accepted behavioural management technique and it includes reinforcement and punishment. The aim and objective of this study was to assess the knowledge of paediatric dentists regarding behavioural management principles related to contingency management. MATERIALS AND METHODS: A cross- sectional survey was conducted among paediatric dental professionals and post-graduate students pursuing masters in paediatric dentistry across Tamil Nadu, India using Knowledge of Behavioural Principles as Applied to Children (KBPAC) questionnaire modified for the dental setting. The data were obtained, tabulated and statistically analysed using SPSS. RESULTS: Responses were obtained from 130 participants, comprising 67 paediatric dental professionals and 63 post-graduate students. The overall average knowledge score was 40.72%. The mean knowledge level of paediatric dental professionals was (0.4378) versus (0.3597) among post-graduate students (p <0.05). CONCLUSION: Knowledge of behavioural management principles related to contingency management among paediatric dentists in Tamil Nadu, India is low.


Subject(s)
Dentists , Pediatric Dentistry , Child , Cross-Sectional Studies , Humans , India , Surveys and Questionnaires
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 233: 118192, 2020 Jun 05.
Article in English | MEDLINE | ID: mdl-32143171

ABSTRACT

This work describes the assignment of the electronic spectra of metal ions in D3d coordination symmetry. Layered hydroxides are a class of materials that host transition metal ions such as Ni2+, Co2+, and Cr3+ in D3d coordination symmetry. The electronic spectra of these ions in the layered hydroxides exhibit significant fine structure which is assigned to transitions arising from D3d coordination symmetry. Towards this end, the correlation diagrams- complete or partial, and the resultant Tanabe-Sugano like diagrams for D3d symmetry are obtained from first principles and supported by DFT based computations. The approach engendered here helps in better understanding of the electronic transitions arising due to lower symmetry.

17.
Phys Chem Chem Phys ; 22(4): 2019-2032, 2020 Jan 28.
Article in English | MEDLINE | ID: mdl-31904062

ABSTRACT

Alkali borate glasses activated with trivalent europium ions and rooted with gold (Au) nanoparticles (NPs) were synthesised through a melt quenching process involving a selective thermochemical reduction and their applicability as photonic materials was assessed in detail. Non-linear optical (NLO) measurements were performed using a Z-scan approach in the wavelength range of 700-1000 nm. The open aperture Z-scan signatures for the Eu3+-containing glasses embedded with and without the Au NPs established a reverse saturable absorption (RSA) at all of the studied wavelengths ascribed to the two-photon absorption (2PA). Surprisingly, the nonlinear optical absorption switched to a saturable absorption (SA) with an increase in the concentration of AuCl3. With the incorporation of the Au NPs, the UV excited photoluminescence (PL) intensity of the Eu3+-doped glasses increased first as a consequence of the local field enhancement by the Au NPs, and subsequently decreased at a higher concentration of AuCl3 due to the reverse energy transfer from the Eu3+ ion to the Au0 NPs. The electronic polarization effect of the host glass enhanced the 5D0→7F4 transition intensity on the incorporation of the gold NPs owing to the gold NP-embedded glasses showing a deep-red emission. The NLO and PL studies suggested that the investigated glasses containing a 0.01 mol% of AuCl3 is practically appropriate for photonic applications.

18.
IEEE J Biomed Health Inform ; 24(6): 1686-1694, 2020 06.
Article in English | MEDLINE | ID: mdl-31545749

ABSTRACT

Transfer learning techniques are recently preferred for the computer aided diagnosis (CAD) of variety of diseases, as it makes the classification feasible from limited training dataset. In this work, an ensemble FCNet classifier is proposed to classify hepatic lesions from the deep features extracted using GoogleNet-LReLU transfer learning approachs. In the existing GoogLeNet architecture three modifications are done: ReLU activation functions in the inception modules are replaced by leaky ReLU activation function; a stack of three fully connected layers are included before the classification layer; and deep features of different level of abstraction extracted from the output of every inception layer given as classifier input in order to significantly enhance the classifier performance. The performance of the proposed classifier by the virtue of the above mentioned modifications is tested on six classes of liver CT images namely normal, hepatocellular carcinoma, hemangioma, cyst, abscess and liver metastasis. The results presented in this work demonstrate the efficacy of the proposed classifier design in achieving better classification accuracy.


Subject(s)
Liver Neoplasms/classification , Liver Neoplasms/diagnostic imaging , Neural Networks, Computer , Radiographic Image Interpretation, Computer-Assisted/methods , Tomography, X-Ray Computed/methods , Algorithms , Humans , Liver/diagnostic imaging
19.
Annu Int Conf IEEE Eng Med Biol Soc ; 2019: 6636-6639, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31947363

ABSTRACT

Ultrasound images(US) of carotid artery aid in the detection and diagnosis of Cardiovascular Diseases (CVD). Traditional methods for analysis of US images employ hand crafted features to classify images, which need expert knowledge for careful design and lack robustness to variations, leading to low sensitivity in clinical applications. Intima Media Thickness (IMT) and elasticity are the predominant markers used for carotid artery (CA) atherosclerotic plaque detection. This paper proposes to address the problem by building Convolutional Neural Network (CNN) for segmentation of intima media complex (ie) Region of Interest (RoI). A dataset consisting of 450 subjects is used to train and validate the proposed CNN. Segmentation is done in the far wall region of the artery from the longitudinal B-mode images enabling atleast 24 RoIs and RoNIs (Region of Non Interest) for each image. The result of 10-fold cross validation shows accuracy of 99.54%. Mean deviation of IMT from manual tracings is found to be 0.06645mm.


Subject(s)
Cardiovascular Diseases , Carotid Intima-Media Thickness , Cardiovascular Diseases/diagnosis , Carotid Arteries , Carotid Artery, Common , Humans , Neural Networks, Computer , Ultrasonography
20.
IET Nanobiotechnol ; 11(1): 91-95, 2017 Feb.
Article in English | MEDLINE | ID: mdl-28476968

ABSTRACT

The combination of the fields of software engineering, gadgets, and science has stood out among the most revolutionary future innovations. Health issues have been the focus of various engaging and explanatory studies. One such health-related dilemma is diabetes. Diabetes at its serious stage results in impaired vision. Increase in the glucose level is a critical parameter that could result in hyperglycaemia, hypoglycaemia, massive heart attack, strokes, and aneurysms. Monitoring the glucose level in blood is one of the control measures for diabetes in the affected population. A glucose monitoring framework interminably measures and screens the glucose level in blood. A novel framework for measuring the glucose level is proposed in this study. This study employs nanopellets that evaluate the glucose level. When the glucose level increases or decreases, it is continuously recorded and displayed using a microcontroller (mixed signal processor (MSP) 430). The data are then sent to the physician through global system for mobile communication. The typical blood glucose level of human being ranges from 70 to 110 mg/dl. When the insulin level builds up to certain point, hyperglycaemia occurs. When decreases, hypoglycaemia occurs. Hyperglycaemia leads to cataracts, oedema, hypertension, polyuria, and polydipsia. Hypoglycaemia causes perplexity, energy, insensateness, coma, and death.


Subject(s)
Biosensing Techniques/instrumentation , Blood Glucose Self-Monitoring/instrumentation , Conductometry/instrumentation , Glucose/analysis , Metal Nanoparticles/chemistry , Signal Processing, Computer-Assisted/instrumentation , Electrodes , Equipment Design , Equipment Failure Analysis , Glucose/chemistry , Metal Nanoparticles/analysis , Reproducibility of Results , Semiconductors , Sensitivity and Specificity
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