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1.
Nanomaterials (Basel) ; 12(17)2022 Aug 24.
Article in English | MEDLINE | ID: mdl-36079940

ABSTRACT

The purpose and novelty of our study include the scrutinization of the unsteady flow and heat characteristics of the unsteady Sutterby nano-fluid flow across an elongated cone using slip boundary conditions. The bioconvection of gyrotactic micro-organisms, Cattaneo-Christov, and thermal radiative fluxes with magnetic fields are significant physical aspects of the study. Anisotropic constraints on the cone surface are taken into account. The leading formulation is transmuted into ordinary differential formate via similarity functions. Five coupled equations with nonlinear terms are resolved numerically through the utilization of a MATLAB code for the Runge-Kutta procedure. The parameters of buoyancy ratio, the porosity of medium, and bioconvection Rayleigh number decrease x-direction velocity. The slip parameter retard y-direction velocity. The temperature for Sutterby fluids is at a hotter level, but its velocity is vividly slower compared to those of nanofluids. The temperature profile improves directly with thermophoresis, v-velocity slip, and random motion of nanoentities.

2.
Nanomaterials (Basel) ; 12(4)2022 Feb 10.
Article in English | MEDLINE | ID: mdl-35214928

ABSTRACT

In this article, we explore how activation energy and varied transit parameters influence the two-dimensional stagnation point motion of nano-biofilm of Sutterby fluids incorporating gyrotactic microbes across a porous straining/shrinking sheet. Prior investigations implied that fluid viscosity as well as thermal conductance are temperature based. This research proposes that fluid viscosity, heat capacity and nanofluid attributes are all modified by solute concentration. According to some empirical research, the viscosity as well as heat conductivity of nanoparticles are highly based on the concentration of nanoparticles instead of only the temperature. The shooting approach with the RK-4 technique is applied to acquire analytical results. We contrast our outcomes with those in the existing research and examine their consistency and reliability. The graphic performance of relevant factors on heat, velocity, density and motile concentration domains are depicted and discussed. The skin friction factor, Nusselt number, Sherwood number and the motile density are determined. As the concentration-dependent properties are updated, the speed, temperature, concentration and motile density profiles are enhanced, but for all concentration-varying factors, other physical quantities deteriorate.

3.
Langmuir ; 37(25): 7730-7740, 2021 Jun 29.
Article in English | MEDLINE | ID: mdl-34128682

ABSTRACT

The development of photoluminescent (PL) systems, displaying multiple stimuli-responsive emission color tuning, has been the pressing priority in the recent times due to their huge role in contemporary lighting and anticounterfeiting technologies. Acknowledging this importance, we present a simple and eco-friendly PL system showing emission color tuning in response to different stimuli, that is, the composition of the system, pH, excitation wavelength, and the temperature with the plus point of getting significantly pure white light emission (WLE). The novel system is fabricated from the aqueous mixture of three organic fluorophores, umbelliferone (UMB), fluorescein (FLU), and Rhodamine-B (RB). By varying the fluorophore composition in the mixture at pH 12, nearly pure WLE with a Commission Internationale d'Eclairage (CIE) 1931 profile of (0.33, 0.33) was obtained at the excitation wavelength of 365 nm, the sustainability of which was ensured by employing the micellar self-assemblies of tetradecyltrimethylammonium bromide (TTAB) molecules. Similar WLE was obtained under mildly acidic conditions (pH 6) but at the excitation wavelength of 330 nm. By proper tuning of pH and the wavelengths of the system to use it as a fluorescent ink, we found a remarkable and highly applicable phenomenon observed for the first time, that is, triple-mode orthogonal emission color tuning with white light ON/OFF switching. We validate the vital applicability of this phenomenon in protecting the authenticity of the document with its hard-to-counterfeit property. The applicability of this phenomenon is also explored by synthesizing PVA-based fluorescent films from the tri-fluorophore mixture. Moreover, the emission color of the PL system was explored lucidly for its temperature dependence owing to the thermal responsiveness of RB emission, where the PL system proves to be a full-color RGB system.

4.
ACS Omega ; 6(23): 14985-15000, 2021 Jun 15.
Article in English | MEDLINE | ID: mdl-34151080

ABSTRACT

The chemical kinetic (CK) method, which involves the reduction of 4-hexadecylbenzenediazonium ions (16-ArN2 +) by antioxidants (in the present case, TBHQ) occurring exclusively at the interface of the association colloids, was employed to establish the changes in the chemical reactivity of anionic surface-active ionic liquids (SAILs) as a function of the concentration and the composition in their mixed states. We used sodium dodecyl sulfate and different SAILs based on the dodecylsulfate surfactant containing 1-alkyl-3-methylimidazolium cations as counterions having a varying alkyl chain length of 4 (bmim), 8 (omim), and 12 (ddmim) carbon atoms. The structural transitions of aggregates of the SAILs from the micellar to vesicular form were observed as a function of concentration in single surfactant systems and as a function of composition in mixed surfactant systems. Results of the reduction kinetics of 16-ArN2 + at the interface of such aggregates, which depends on the acid/base equilibria at the interface, gave an insight into the changes in the interfacial H+ ions with the change in the hydrophobicity of the counterions of SAILs and the morphological changes from micelles to vesicles as a function of concentration or composition. These changes in the interfacial pH correlate very well with the stability of curcumin within these self-assemblies, which exclusively depends on the pH of the medium and highlights the importance of the results obtained from the CK method in selecting the appropriate medium/conditions for the stabilization of the bioactive molecules.

5.
ACS Omega ; 6(18): 11974-11987, 2021 May 11.
Article in English | MEDLINE | ID: mdl-34056352

ABSTRACT

The mixture of the cationic surfactant, cetyltrimethylammonium bromide (CTAB), and anionic surface-active ionic liquid, 1-butyl-3-methylimidazoliumdodecyl sulfate (bmimDS), has been studied as a function of the mole fraction of CTAB, X CTAB, with the total surfactant concentration fixed at 50 mM using turbidity measurements, rheology, dynamic light scattering, differential scanning calorimetry, small-angle neutron scattering, and small-angle X-ray scattering techniques. The catanionic mixture has been found to exhibit phase transitions from vesicles to micelles as a function of temperature, with some mole fractions of CTAB showing dual transitions. Solutions of X CTAB = 0.2 to 0.5 exhibited a single transition from vesicles to cylindrical micelles at 45 °C. With an increase in the mole fraction of CTAB from 0.55 to 0.65, dual structural transitions at 30 and 45 °C were observed. The microstructural transition at 30 °C is ascribed to the vesicle aggregation process with smaller vesicles fusing into bigger ones, whereas the transition at 45 °C was evaluated to be the vesicle-to-cylindrical micelle transition. However, at higher mole fractions of CTAB, X CTAB from 0.65 to 0.90, a single transition from vesicles to small cylindrical/spherical micelles was observed in the solutions, at a lower temperature of 30 °C. To the best of our knowledge, such a microstructural transitions as a function of temperature in a single mixture of cationic and anionic surfactants without any additive has not been reported so far.

6.
J Thromb Thrombolysis ; 52(2): 646-653, 2021 Aug.
Article in English | MEDLINE | ID: mdl-33666824

ABSTRACT

Direct-acting oral anticoagulants (DOACs) are replacing conventional VKA (vitamin K antagonist, i.e., warfarin) for various indications where a therapeutic anticoagulant effect is desired. We evaluated the prescribing patterns of the DOACs and warfarin, cost implications of the increasing DOACs prescribing, and deduce the reporting of serious and fatal events, during 2009-2019 in primary care England. Prescriptions and fatal or serious adverse events reporting data, between 2009 and 2019 were analysed, using linear regression to examine the trends in prescriptions, costs, and serious and fatal events reporting. We also compared the prescribing trends of four direct-acting oral anticoagulants and warfarin, normalised to per 1000 clinical commissioning group (CCG) patient population for the year 2019 to better understand the regional differences in DOACs prescribing. The overall use of any DOACs (as a proportion of total anticoagulants) increased from 16% in 2015 to 62% in 2019 with an average increase of 87% (95% CI 83.1, 90.5) per year. The reporting of serious and fatal events associated with DOACs decreased by 6% (95% CI 12.5, - 0.1) per year. Apixaban is by far the most prescribed with an average drug cost increasing to 156% (95% CI 140, 172) per year. In England, the lowest anticoagulant prescribing region was Greater London whereas the highest prescribing regions were Yorkshire and Humber for DOACs and the East Midlands for warfarin. Interestingly, Lancashire, Merseyside, and Cheshire showed a higher usage for warfarin over DOACs. The differing prescription patterns could be a result of changes in national guidelines and increasing population. Nevertheless, DOACs appear to make an increasing contribution to total anticoagulant prescription items and costs.


Subject(s)
Anticoagulants/therapeutic use , Drug-Related Side Effects and Adverse Reactions/epidemiology , Practice Patterns, Physicians' , Administration, Oral , Anticoagulants/adverse effects , Atrial Fibrillation/drug therapy , England/epidemiology , Factor Xa Inhibitors/therapeutic use , Humans , Stroke/drug therapy , Warfarin/adverse effects
7.
Soft Matter ; 17(3): 425-446, 2021 Jan 21.
Article in English | MEDLINE | ID: mdl-33400748

ABSTRACT

The self-assembled systems of surfactants/polymers, which are capable of supporting energy funneling between fluorophores, have recently gained significant attraction. Surfactant and polymeric micelles form nanoscale structures spanning a radius of 2-10 nm are generally suitable for the transduction of energy among fluorophores. These systems have shown great potential in Förster resonance energy transfer (FRET) due to their unique characteristics of being aqueous based, tendency to remain self-assembled, spontaneous formation, tunable nature, and responsiveness to different external stimuli. This review presents current developments in the field of energy transfer, particularly the multi-step FRET processes in the self-assembled nanostructures of surfactants/polymers. The part one of this review presents a background and brief overview of soft systems and discusses certain aspects of the self-assemblies of surfactants/polymers and their co-solubilization property to bring fluorophores to close proximity to transduce energy. The second part of this review deals with single-step and multi-step FRET in the self-assemblies of surfactants/polymers and links FRET systems with advanced smart technologies including multicolor formation, data encryption, and artificial antenna systems. This review also discusses the diverse examples in the literature to present the emerging applications of FRET. Finally, the prospects regarding further improvement of FRET in self-assembled soft systems are outlined.

8.
Food Chem ; 376: 131925, 2021 Dec 23.
Article in English | MEDLINE | ID: mdl-34973641

ABSTRACT

Nanoemulsion encapsulated in the hydrogel beads are important entrants for loading hydrophobic active ingredients for enhancing their bioavailability and biological activities relevant in the pharmaceutical, food and cosmetic industries. Herein, we report the formulation of curcumin-loaded nanoemulsion encapsulated in ionotropic hybrid hydrogel beads of alginate, chitosan, gelatin and polyethylene oxide for effective delivery of curcumin. The release behaviour in simulated gastric and intestinal fluids (SGF and SIF) at 37 °C showed faster release in SGF which could be explained on the basis of mesh size, the extent of hydration and the complexation of the curcumin with the Ca2+ ions present within the hydrogel network. The free radical scavenging and antibacterial activities of the released curcumin in SGF were significantly greater than in SIF. This study shows promises of such hybrid systems, ignored so far, for proper encapsulation, protection and delivery of curcumin for the development of functional foods and pharmaceutics. The high structural stability of these nanoemulsion carriers and their effective delivery of curcumin provide a novel and tailored formulation out of existing polymers with plethora of advantages for oral drug delivery. Moreover, this study opens new door for different possibilities to improve the physicochemical characteristics and delivery of bioactive molecules like curcumin.

9.
Chemosphere ; 242: 125160, 2020 Mar.
Article in English | MEDLINE | ID: mdl-31669988

ABSTRACT

Surfactant enhanced remediation (SER) is an effective approach for decontaminating the PAH polluted soils. Solubilization and Cosolubilization of Phenanthrene (Ph), Pyrene (Py) and Perylene (Pe) as single, binary and ternary mixtures have been studied employing cationic (CTAB), anionic (SDS), non-ionic surfactant (Brij 30) and block copolymer (P123) micelles. In the single solute solubilization studies, solubility of Pe follows the order Brij 30 > CTAB > SDS whereas Ph or Py followed the order of CTAB > Brij 30 > SDS. In the cosolubilization studies, an increase, decrease or no change in the mutual solubility of PAHs was observed. Synergism in solubilization was observed most in P123 in both binary and ternary PAH mixture where more PAHs could get solubilized in the dense micellar shell region, thereby enhancing the micellar core volume leading to enhanced solubilization of PAHs. The solubilizates as pairs (Ph-Pe and Py-Pe) were further tested for any possible energy transfer in presence of surfactant based restricted host environments using spectrofluorometry and spectrophotometry. Based on the solubilization and cosolubilization an efficient non-radiative energy transfer (FRET) was observed between Ph/Py (donor) and Pe (acceptor) in the non-ionic surfactant system as well as in CTAB-Brij 58 mixed system. The results of this work may improve the effective utilization of surfactants in their correct evaluation for the removal of PAHs from contaminated soils or aquifers treated with SER technology.


Subject(s)
Environmental Restoration and Remediation/methods , Fluorescence Resonance Energy Transfer/methods , Micelles , Polycyclic Aromatic Hydrocarbons/chemistry , Surface-Active Agents/chemistry , Phenanthrenes/chemistry , Phenanthrenes/isolation & purification , Polycyclic Aromatic Hydrocarbons/isolation & purification , Pyrenes/chemistry , Pyrenes/isolation & purification , Soil Pollutants/chemistry , Soil Pollutants/isolation & purification , Solubility , Water
10.
J Phys Chem B ; 123(45): 9699-9711, 2019 11 14.
Article in English | MEDLINE | ID: mdl-31640345

ABSTRACT

A broad spectrum tunable photoluminescent material with dual encryption based on a two-step fluorescence resonance energy transfer (FRET) between pyrene (Py), coumarin 480 (Cou480), and rhodamine 6G (R6G) in micelles of SDS and bmimDS is presented. The phenomenon is achievable due to the encapsulation of the fluorophores within these micelles. The transfer of energy as FRET between the pair Py and Cou480 showed ON at 336 nm and OFF at 402 nm in contrast to the FRET observed between the pair Cou480 and R6G that showed ON at 402 nm and OFF at 336 nm. However, the transfer of energy as FRET occurs from Py to R6G in the presence of Cou480 when excited at 336 nm, thereby making it a chain of three fluorophores with Cou480 acting as a relay fluorophore receiving energy from Py and transferring it to R6G. The different FRET scenarios between the three fluorophores in micelles provide a window for the generation of a matrix of colors, which occupies a significant 2D area in the chromaticity diagram, having potential applications in security printing. The different fluorophoric ratios generate different colors based on their individual photonic emissions and the FRET processes taking place between them. Writing tests were carried out using varied ratios of the fluorophores in the micellar systems producing different colored outputs under the UV light with insignificant visibility under the white light. We envision that this as-discovered three fluorophoric FRET system could form the basis for the future development of multi-FRET light-harvesting devices and anti-counterfeiting security inks based on much simpler non-covalent interaction aided encapsulation of the fluorophores within the self-assembled soft systems.

11.
Br J Clin Pharmacol ; 85(12): 2652-2667, 2019 12.
Article in English | MEDLINE | ID: mdl-31077431

ABSTRACT

AIMS: Patient-reported outcomes (PROs) are a distinctive method of evaluating patient response to health care or treatment. This systematic review aimed to analyse the impact of PROs in patients on direct oral anticoagulant (DOAC) treatment, prescribed for any indication (e.g. venous thromboembolism treatment or atrial fibrillation) using controlled trials (CT) and real-world observational studies (OS). METHODS: A systematic search of articles was conducted according to PRISMA guidelines using databases, with the last update in November 2018. The Cochrane Collaboration tool for assessing bias in randomized CTs and the Newcastle-Ottawa Scale adapted for cross-sectional studies were used. Outcomes evaluated were related to health-related quality of life (HRQoL), satisfaction, adherence and compliance. RESULTS: Twenty-one original studies (6 CT, 15 OS) were included. HRQoL was assessed by 6 (1 CT, 5 OS) studies and reported that HRQoL scores were similar in patients on DOACs and warfarin. Patients prescribed DOACs presented higher HRQoL scores which were attributed to lack of intense monitoring required compared with warfarin but this was not statistically significant. The majority of studies (5 CT, 9 OS) investigated patient-reported satisfaction, indicating greater satisfaction with DOACs with significantly lower burden and increased benefit scores for patients on DOACs. Patient-reported expectations, compliance and adherence were similar for patients on DOACs and warfarin. CONCLUSION: Patients appear to prefer treatment with DOACs vs warfarin. This is shown by the higher quality of life, satisfaction and adherence described in the studies. However, heterogeneity in the analysed studies does not allow firm conclusions.


Subject(s)
Clinical Trials as Topic , Factor Xa Inhibitors , Patient Reported Outcome Measures , Administration, Oral , Factor Xa Inhibitors/administration & dosage , Factor Xa Inhibitors/adverse effects , Factor Xa Inhibitors/therapeutic use , Humans , Medication Adherence , Patient Satisfaction , Quality of Life
12.
Res Social Adm Pharm ; 15(10): 1236-1242, 2019 10.
Article in English | MEDLINE | ID: mdl-30396826

ABSTRACT

BACKGROUND: Warfarin-related knowledge and patient satisfaction with warfarin monitoring services are generally high with respect to anticoagulation-related care received. Providing a cost-effective warfarin monitoring service while improving warfarin-related knowledge, patient safety and satisfaction can be challenging. OBJECTIVES: To compare 'post and dose' service offered by the Calderdale Royal Hospital (CRH) and 'face-to-face' service offered by Huddersfield Royal Infirmary (HRI) in terms of costs of service delivery, patient satisfaction, warfarin-related knowledge and safety indicators. METHODS: A cross-sectional sample of 160 patients on long-term warfarin therapy from anticoagulation (outpatient) clinics at CRH and HRI using interviewer-administered data collection form. International Normalized Ratio (INR), Time in Therapeutic Range (TTR) and Variance Growth Rate (VGR) values of last 12 months and the data on costs of service delivery, knowledge and satisfaction were collected. RESULTS: Patients monitored at HRI had higher mean VGR value (0.35 ± 0.62 vs. 0.17 ± 0.17, p = 0.092) and slightly lower mean TTR (68.70 ± 19.43 vs. 69.63 ± 17.71, p = 0.756) compared with CRH patients. Patients monitored in 'post and dose' were estimated at a price of £11.06 per patient per visit and each patient in face-to-face service only cost £9.70 per visit. Patients monitored at HRI had marginally higher overall knowledge score (65.22 ± 23.29 vs. 60.31 ± 20.93, p = 0.165) and overall satisfaction score (15.59 ± 3.16 vs. 15.05 ± 3.10, p = 0.279) compared with CRH patients. A positive and significant correlation was found between patients' knowledge and patient satisfaction (r = +0.327, p = 0.001). CONCLUSION: Although, HRI provided monitoring service at a slightly lower cost than CRH, patients monitored at CRH had better anticoagulation control and favourable indicators. Warfarin-related knowledge needs to be improved to achieve further improvement in quality of warfarin use.


Subject(s)
Anticoagulants/administration & dosage , Drug Monitoring/methods , Patient Satisfaction/statistics & numerical data , Warfarin/administration & dosage , Adolescent , Adult , Aged , Aged, 80 and over , Ambulatory Care Facilities/economics , Anticoagulants/adverse effects , Cross-Sectional Studies , Female , Health Knowledge, Attitudes, Practice , Humans , International Normalized Ratio , Male , Middle Aged , Warfarin/adverse effects , Young Adult
13.
Colloids Surf B Biointerfaces ; 169: 99-106, 2018 09 01.
Article in English | MEDLINE | ID: mdl-29753183

ABSTRACT

The pure and composite hydrogels of chitosan with sodium alginate were synthesized at various pH values and characterized by rheology and IR-spectroscopy. Chitosan shows gelation at neutral and basic pH while sodium alginate remains in solution form at all pH values. By careful adjustment of mixing weight fraction ratio and pH, an array of hydrogels with modulated structural dynamics and viscoelasticity, mechanical strength and encapsulation capacity were obtained. At acidic pH, a higher weight fraction of alginate increased the elasticity of the hydrogels while at basic pH more percentage of chitosan stabilized the hydrogel. Strongest composite hydrogels were obtained at acidic pH and gel strength decreased on increasing pH of the synthetic medium. The synthesized hydrogels were studied for their encapsulation capability towards Citral. The pure chitosan hydrogels showed maximum encapsulation capacity followed by the composite hydrogels prepared at neutral pH. This study highlights that a range of composite hydrogels with modified properties can be obtained by simple changes in experimental conditions exploiting physical interactions and can help in better understanding of niche of its applicability in research and industry.


Subject(s)
Alginates/chemistry , Chitosan/chemistry , Hydrogels/chemistry , Monoterpenes/chemistry , Acyclic Monoterpenes , Capsules/chemistry , Hydrogels/chemical synthesis , Hydrogen-Ion Concentration , Molecular Structure , Rheology , Spectrophotometry, Infrared
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