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1.
J Fluoresc ; 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38319520

RESUMO

A green developed spectrofluorimetric method has been applied for Antazoline (ANT) and Xylometazoline (XLO) determination in both pharmaceutical formulation and pure form. The developed method is synchronous spectrofluorimetry coupled with the second derivative mathematical tool for the determination of antazoline and xylometazoline in their dosage form. The developed method depends on reacting the cited drugs with dansyl chloride, a suitable derivatizing agent, to generate highly fluorescent derivatives. The products formed were measured at emission wavelengths; 703.0 and 712.0 nm after being excited at wavelengths; 350.0 and 355.0 nm for antazoline and xylometazoline, respectively. Synchronous spectrofluorimetry coupled with second derivative mathematical tool was developed and optimized using fluorescence data manager software generating second derivative peak amplitudes at 556.5 nm for antazoline and 598.0 nm for xylometazoline. Linear responses have been represented over a wide range of concentration 0.5-12.0 µg/mL for antazoline and 0.1-10.0 µg/mL for xylometazoline, correspondingly. Method validation was successfully applied. Additionally, statistical comparison of developed method with official ones has been carried out where no significant difference was found. Evaluation of the method's greenness was proven using several assessment tools. Indeed, the method developed is found to be precise, sensitive, and discriminating to assess the cited drugs for regular analysis.

2.
Luminescence ; 39(3): e4728, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38516711

RESUMO

A novel spectrofluorimetric method has been developed for determination of antazoline (ANT) and tetryzoline (TET) in their pharmaceutical formulation. A combined application of synchronous spectrofluorimetry and second derivative mathematical treatment was developed. The proposed method depends on reacting the cited drugs with dansyl chloride (DNS-Cl) being a suitable derivatizing agent generating highly fluorescent derivatives measured at emission wavelengths of 703.0 and 642.0 nm after excitation wavelengths of 350.0 and 320.0 nm for ANT and TET, respectively. The joint use of synchronous spectrofluorimetry with second derivative mathematical treatment is for the first time to be developed and optimized in aid of using fluorescence data manager software generating second derivative peak amplitudes at 556.5 nm for ANT and 516.7 nm for TET. Linear responses have been represented over a wide range of concentration (0.5-12.0 µg/mL for ANT and 0.5-10.0 µg/mL for TET). Additionally, statistical comparison of the developed method with the official ones has been carried out where no significant difference was found. Additionally, greenness profile assessment was accomplished by means of four metric tools. Indeed, the method developed is found to be precise, sensitive, and discriminating to assess the cited drugs for regular analysis.


Assuntos
Antazolina , Antazolina/análise , Espectrometria de Fluorescência/métodos , Imidazóis
3.
Mod Rheumatol ; 33(4): 830-835, 2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35789271

RESUMO

OBJECTIVE: To explore early features that can predict colchicine resistance in familial Mediterranean fever (FMF) patients. METHODS: It included FMF cases who fulfilled the Yalcinkaya-Ozen criterion and were on colchicine for at least 6 months. Data were collected from medical files and interpreted with respect to clinical parameters, incluing the auto-inflammatory diseases activity index (AIDAI) and FMF severity score. FMF50 score assessed the treatment response. Laboratory findings and genetic analysis of Mediterranean fever (MEFV) mutations were evaluated according to the standard technique. Patients were classified into two groups according to their response to colchicine. Both groups were compared, and significant variables were entered into a logistic regression model to detect independent predictors. The diagnostic accuracy of these predictors was assessed using the receiver operating characteristic curve. RESULTS: In all, 120 FMF children were included. After the exclusion of 16 non-compliant patients (13.3%), colchicine responders were 66 (63.4%) (group I) and colchicine-resistant cases (group II) were 38 (36.5%). The fever duration after colchicine, number of attacks before/after colchicine, skin rash/erysipelas-like erythema, myalgia/protracted febrile myalgia, AIDAI before/after treatment, FMF severity score, and the maximum colchicine dose were higher in group II. Furthermore, high C-reactive protein and neutropenia were frequent in group II. However, different MEFV mutations, including M694V were similar between the two groups. Eight variables were detected in the regression analysis model, and independent predictors were utilized to generate a scoring model. CONCLUSION: This study constructed a prediction model for colchicine nonresponse based on clinical and laboratory profiles. This model will be valuable for the treatment decisions of FMF children.


Assuntos
Febre Familiar do Mediterrâneo , Criança , Humanos , Febre Familiar do Mediterrâneo/diagnóstico , Febre Familiar do Mediterrâneo/tratamento farmacológico , Febre Familiar do Mediterrâneo/genética , Mialgia/tratamento farmacológico , Genótipo , Colchicina/uso terapêutico , Mutação , Pirina/genética
4.
Clin Oral Investig ; 26(3): 3311-3323, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34985576

RESUMO

OBJECTIVES: The aim of this study is to investigate vascular and neurosensory complications in edentulous patients following the installation of mandibular midline single implants in relation to lingual canals. MATERIALS AND METHODS: After performing a cone beam computed tomography scan for the 50 recruited patients, the relationship between the potential implant site and the lingual canals was assessed, and all vascular and neurosensory complications were recorded. RESULTS: Six patients (12%) reported profuse bleeding during implant placement, and 13 (26%) reported transient neurosensory changes, which were resolved after 3 months. According to the virtual implant planning, 44 patients (88%) would have their implants touching the lingual canals, six of them reported vascular changes (14%), and 12 out of 44 patients reported neurosensory changes (27%). For the six patients who would have their implants not touching the lingual canals, one patient reported transient neurosensory changes. CONCLUSIONS: The mandibular lingual canals are constant anatomic landmarks. Injury to the supra-spinosum lingual canals may occur during midline implant placement, depending on the implant length and the bone height. CLINICAL RELEVANCE: Despite that injury to the supra-spinosum lingual canals during implant insertion does not result in permanent vascular or neurosensory complications, caution is required to avoid the perforation of the lingual cortices.


Assuntos
Implantes Dentários , Mandíbula , Pontos de Referência Anatômicos , Tomografia Computadorizada de Feixe Cônico , Implantação Dentária Endóssea/métodos , Humanos , Mandíbula/anatomia & histologia , Mandíbula/diagnóstico por imagem , Mandíbula/cirurgia
5.
Sensors (Basel) ; 22(19)2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-36236297

RESUMO

Passengers commute between different modes of transportation in traffic hubs, and passenger localization is a key component for the effective functioning of these spaces. The smartphone-based localization system presented in this work is based on the 3D step and heading approach, which is adapted depending on the position of the smartphone, i.e., held in the hand or in the front pocket of the trousers. We use the accelerometer, gyroscope and barometer embedded in the smartphone to detect the steps and the direction of movement of the passenger. To correct the accumulated error, we detect landmarks, particularly staircases and elevators. To test our localization algorithm, we have recorded real-world mobility data in a test station in Munich city center where we have ground truth points. We achieve a 3D position accuracy of 12 m for a smartphone held in the hand and 10 m when the phone is placed in the front pocket of the trousers.


Assuntos
Smartphone , Meios de Transporte , Algoritmos , Cidades
6.
Int J Mol Sci ; 22(23)2021 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-34884657

RESUMO

This study deals with the process of optimization and synthesis of Poly(3-hydroxybutyrate) microspheres with encapsulated Cl-amidine. Cl-amidine is an inhibitor of peptidylarginine deiminases (PADs), a group of calcium-dependent enzymes, which play critical roles in a number of pathologies, including autoimmune and neurodegenerative diseases, as well as cancer. While Cl-amidine application has been assessed in a number of in vitro and in vivo models; methods of controlled release delivery remain to be investigated. P(3HB) microspheres have proven to be an effective delivery system for several compounds applied in antimicrobial, wound healing, cancer, and cardiovascular and regenerative disease models. In the current study, P(3HB) microspheres with encapsulated Cl-amidine were produced in a size ranging from ~4-5 µm and characterized for surface morphology, porosity, hydrophobicity and protein adsorption, in comparison with empty P(3HB) microspheres. Cl-amidine encapsulation in P(3HB) microspheres was optimized, and these were found to be less hydrophobic, compared with the empty microspheres, and subsequently adsorbed a lower amount of protein on their surface. The release kinetics of Cl-amidine from the microspheres were assessed in vitro and expressed as a function of encapsulation efficiency. There was a burst release of ~50% Cl-amidine in the first 24 h and a zero order release from that point up to 16 days, at which time point ~93% of the drug had been released. As Cl-amidine has been associated with anti-cancer effects, the Cl-amidine encapsulated microspheres were assessed for the inhibition of vascular endothelial growth factor (VEGF) expression in the mammalian breast cancer cell line SK-BR-3, including in the presence of the anti-proliferative drug rapamycin. The cytotoxicity of the combinatorial effect of rapamycin with Cl-amidine encapsulated P(3HB) microspheres was found to be 3.5% more effective within a 24 h period. The cells treated with Cl-amidine encapsulated microspheres alone, were found to have 36.5% reduction in VEGF expression when compared with untreated SK-BR-3 cells. This indicates that controlled release of Cl-amidine from P(3HB) microspheres may be effective in anti-cancer treatment, including in synergy with chemotherapeutic agents. Using controlled drug-delivery of Cl-amidine encapsulated in Poly(3-hydroxybutyrate) microspheres may be a promising novel strategy for application in PAD-associated pathologies.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Inibidores Enzimáticos/administração & dosagem , Hidroxibutiratos/administração & dosagem , Ornitina/análogos & derivados , Poliésteres/administração & dosagem , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Sistemas de Liberação de Medicamentos , Inibidores Enzimáticos/química , Feminino , Humanos , Hidroxibutiratos/química , Microesferas , Ornitina/administração & dosagem , Ornitina/química , Poliésteres/química , Desiminases de Arginina em Proteínas/antagonistas & inibidores , Células Tumorais Cultivadas , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
7.
Molecules ; 26(12)2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34198519

RESUMO

Poly(vinyl chloride) degrades when exposed to ultraviolet light for long durations; therefore, the photostability of polymeric materials should be enhanced through the application of additives. New organotin complexes containing 4-aminonaphthalene-1-sulfonic acid were synthesized and their role as poly(vinyl chloride) photostabilizers were evaluated. The reaction of 4-amino-3-hydroxynaphthalene-1-sulfonic acid and appropriate di- or trisubstituted tin chloride (triphenyltin chloride, tributyltin chloride, dibutyltin dichloride, and dimethyltin dichloride) in methanol under reflux gave the corresponding tin-naphthalene complexes with yields of 75%-95%. Elemental analyses and spectroscopic techniques including infrared and nuclear magnetic resonance (proton and tin) were used to confirm their structures. The tin complexes were added to poly(vinyl chloride) to produce thin films that irradiated with ultraviolet light. Various parameters were assessed, such as the weight loss, formation of specific functional groups, changes in the surface due to photoirradiation, and rate constant of photodegradation, to test the role played by the organotin complexes to reduce photodegradation in polymeric films. The results proved that organotin complexes acted as photostabilizers in these circumstances. The weight loss, formation of fragments containing specific functional groups, and undesirable changes in the surface of polymeric films were limited in the presence of organotin complexes. Organotin complexes containing three phenyl groups showed the most desirable stabilization effect. These act as efficient primary and secondary photostabilizers, and as decomposers for peroxides. In addition, such an additive inhibits the dehydrochlorination process, which is the main cause of poly(vinyl chloride) photodegradation.

8.
Sensors (Basel) ; 20(18)2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-32962170

RESUMO

In this article, we present a novel tight coupling inertial localization system which simultaneously processes the measurements of two inertial measurement units (IMUs) mounted on the leg, namely the upper thigh and the front part of the foot. Moreover, the proposed system exploits motion constraints of each leg link; that is, the thigh and the foot. To derive these constraints, we carry out a motion tracking experiment to collect both ground truth data and inertial measurements from IMUs mounted on the leg. The performance of the tight coupling system is assessed with a data set of approximately 10 h. The evaluation shows that the average 2D-position error of the proposed tight coupling system is at least 50% better than the average 2D-position error of two state-of-the-art systems, whereas the average height error of the tight coupling system is at least 75% better than the average height error of the two state-of-the-art systems. In this work, we improve the accuracy of the position estimation by introducing biomechanical constraints in an inertial localization system. This article allows to observe, for the first time, heading errors of an inertial localization system by using only inertial measurements and without the need for using maps or repeating totally or partially the walked trajectory.


Assuntos
Pedestres , Caminhada , Fenômenos Biomecânicos , , Cabeça , Humanos , Movimento (Física)
9.
Sensors (Basel) ; 20(7)2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32272805

RESUMO

All non-foot-mounted inertial localization systems have a common challenge: the need for calibrating the parameters of the step length model. The calibration of the parameters of a step length model is key for an accurate estimation of the pedestrian's step length, and therefore, for the accuracy of the position estimation. In a previous work, we provided a proof of concept on how to calibrate step length models with a foot inertial navigation system (INS), i.e., an INS based on an inertial measurement unit (IMU) mounted on the upper front part of the foot. The reason is that the foot INS does not require calibration thanks to the implementation of the strapdown algorithm. The goal of this article is to automatically calibrate the parameters of a step length model of the pocket INS by means of the foot INS. The step length model of the pocket INS has two parameters: the slope and offset of a first-order linear regression that relates the amplitude of the thigh pitch with the user's step length. Firstly, we show that it is necessary to estimate the two parameters of the step length model. Secondly, we propose a method to automatically estimate these parameters by means of a foot INS. Finally, we propose a practical implementation of the proposed method in the pocket INS. We evaluate the pocket INS with the proposed calibration method and we compare the results to the state of the art implementations of the pocket INS. The results show that the proposed automatic calibration method outperforms the previous work, which proves the need for calibrating all the parameters of the step length model of the pocket INS. In this work, we conclude that it is possible to use a foot INS to automatically calibrate all parameters of the step length model of the pocket INS. Since the calibration of the step length model is always needed, our proposed automatic calibration method is a key enabler for using the pocket INS.


Assuntos
Pé/fisiologia , Caminhada , Automação , Calibragem , Humanos , Modelos Teóricos , Caminhada/normas , Dispositivos Eletrônicos Vestíveis/normas
10.
Molecules ; 24(19)2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31581427

RESUMO

Poly(vinyl chloride) (PVC), a polymer widely used in common household and industrial materials, undergoes photodegradation upon ultraviolet irradiation, leading to undesirable physicochemical properties and a reduced lifetime. In this study, four telmisartan organotin(IV) compounds were tested as photostabilizers against photodegradation. PVC films (40-µm thickness) containing these compounds (0.5 wt%) were irradiated with ultraviolet light at room temperature for up to 300 h. Changes in various polymeric parameters, including the growth of hydroxyl, carbonyl, and alkene functional groups, weight loss, reduction in molecular weight, and appearance of surface irregularities, were investigated to test the efficiency of the photostabilizers. The changes were more noticeable in the blank PVC film than in the films containing the telmisartan organotin(IV) compounds. These results reflect that these compounds effectively inhibit the photodegradation of PVC, possibly by acting as hydrogen chloride and radical scavengers, peroxide decomposers, and primary photostabilizers. The synthesized organotin(IV) complexes could be used as PVC additives to enhance photostability.


Assuntos
Compostos Orgânicos de Estanho/síntese química , Cloreto de Polivinila/química , Telmisartan/química , Ácido Clorídrico/química , Estrutura Molecular , Peso Molecular , Compostos Orgânicos de Estanho/química , Fotólise , Espectroscopia de Infravermelho com Transformada de Fourier
11.
Molecules ; 24(8)2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31027205

RESUMO

Novel, porous, highly aromatic organotin(IV) frameworks were successfully synthesized by the condensation of telmisartan and an appropriate tin(IV) chloride. The structures of the synthesized organotin(IV) complexes were elucidated by elemental analysis, 1H-, 13C-, and 119Sn-NMR, and FTIR spectroscopy. The surface morphologies of the complexes were inspected by field emission scanning electron microscopy. The synthesized mesoporous organotin(IV) complexes have a Brunauer-Emmett-Teller (BET) surface area of 32.3-130.4 m2·g-1, pore volume of 0.046-0.162 cm3·g-1, and pore size of around 2.4 nm. The tin complexes containing a butyl substituent were more efficient as carbon dioxide storage media than the complexes containing a phenyl substituent. The dibutyltin(IV) complex had the highest BET surface area (SBET = 130.357 m2·g-1), the largest volume (0.162 cm3·g-1), and was the most efficient for carbon dioxide storage (7.1 wt%) at a controlled temperature (323 K) and pressure (50 bars).


Assuntos
Dióxido de Carbono/química , Carbono/química , Telmisartan/química , Adsorção , Microscopia Eletrônica de Varredura
12.
Molecules ; 24(13)2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31261834

RESUMO

As poly(vinyl chloride) (PVC) photodegrades with long-term exposure to ultraviolet radiation, it is desirable to develop methods that enhance the photostability of PVC. In this study, new aromatic-rich diorganotin(IV) complexes were tested as photostabilizers in PVC films. The diorganotin(IV) complexes were synthesized in 79-86% yields by reacting excess naproxen with tin(IV) chlorides. PVC films containing 0.5 wt % diorganotin(IV) complexes were irradiated with ultraviolet light for up to 300 h, and changes within the films were monitored using the weight loss and the formation of specific functional groups (hydroxyl, carbonyl, and polyene). In addition, changes in the surface morphologies of the films were investigated. The diorganotin(IV) complexes enhanced the photostability of PVC, as the weight loss and surface roughness were much lower in the films with additives than in the blank film. Notably, the dimethyltin(IV) complex was the most efficient photostabilizer. The polymeric film containing this complex exhibited a morphology of regularly distributed hexagonal pores, with a honeycomb-like structure-possibly due to cross-linking and interactions between the additive and the polymeric chains. Various mechanisms, including direct absorption of ultraviolet irradiation, radical or hydrogen chloride scavenging, and polymer chain coordination, could explain how the diorganotin(IV) complexes stabilize PVC against photodegradation.


Assuntos
Naproxeno/química , Compostos Orgânicos de Estanho/química , Cloreto de Polivinila/síntese química , Membranas Artificiais , Estrutura Molecular , Fotólise , Cloreto de Polivinila/química , Propriedades de Superfície , Raios Ultravioleta
13.
Molecules ; 24(4)2019 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-30813367

RESUMO

Five Schiff bases derived from melamine have been used as efficient additives to reduce the process of photodegradation of poly(vinyl chloride) films. The performance of Schiff bases has been investigated using various techniques. Poly(vinyl chloride) films containing Schiff bases were irradiated with ultraviolet light and any changes in their infrared spectra, weight, and the viscosity of their average molecular weight were investigated. In addition, the surface morphology of the films was inspected using a light microscope, atomic force microscopy, and a scanning electron micrograph. The additives enhanced the films resistance against irradiation and the polymeric surface was much smoother in the presence of the Schiff bases compared with the blank film. Schiff bases containing an ortho-hydroxyl group on the aryl rings showed the greatest photostabilization effect, which may possibly have been due to the direct absorption of ultraviolet light. This phenomenon seems to involve the transfer of a proton as well as several intersystem crossing processes.


Assuntos
Cloreto de Polivinila/química , Bases de Schiff/química , Triazinas/química , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Estrutura Molecular , Fotólise , Raios Ultravioleta
14.
Sensors (Basel) ; 18(3)2018 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-29547581

RESUMO

Shoe-mounted inertial sensors are widespread deployed in satellite-denied scenarios because of the possibility to re-calibrate stepwise the estimated position. These re-calibrations, known as zero-velocity corrections, prevent an accumulated positioning error growth over time caused by the noise of current medium- and low-cost sensors. However, the error accumulated over time in the height estimation is still an issue under study. The objective of this article is to propose a height correction that is based on the dynamics of the foot. The presented algorithm analyzes the movement of the foot, which is different when walking on horizontal surfaces and stairs. The identification of horizontal surfaces and stairs is detailed in this article. For the assessment of the performance of the proposed height correction, a dataset of approximately 5 h recorded with 10 volunteers walking in a five-story building is employed. The error is evaluated using pre-defined ground truth points. We compare the height error estimated with and without applying the proposed correction and show that the height correction improves the vertical positioning accuracy up to 85.


Assuntos
Sapatos , Algoritmos , Calibragem , , Humanos , Caminhada
15.
Molecules ; 23(2)2018 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-29382088

RESUMO

Three organotin(IV) complexes containing ciprofloxacin as a ligand (Ph3SnL, Me2SnL2 and Bu2SnL2; 0.5% by weight) were used as additives to inhibit the photodegradation of polyvinyl chloride films (40 µm thickness) upon irradiation with ultraviolet light (λmax = 313 at a light intensity = 7.75 × 10-7 ein dm-3 S-1) at room temperature. The efficiency of organotin(IV) complexes as photostabilizers was determined by monitoring the changes in the weight, growth of specific functional groups (hydroxyl, carbonyl and carbene), viscosity, average molecular weight, chain scission and degree of deterioration of the polymeric films upon irradiation. The results obtained indicated that organotin(IV) complexes stabilized poly(vinyl chloride) and the dimethyltin(IV) complex was the most efficient additive. The surface morphologies of poly(vinyl chloride) films containing organotin(IV) complexes were examined using an atomic force microscope and scanning electron microscopy. These showed that the surface of polymeric films containing organotin(IV) complexes were smoother and less rough, compared to the surface of the blank films. Some mechanisms that explained the role of organotin(IV) complexes in poly(vinyl chloride) photostabilization process were proposed.


Assuntos
Membranas Artificiais , Compostos Orgânicos de Estanho/química , Cloreto de Polivinila/química , Raios Ultravioleta , Propriedades de Superfície
16.
Molecules ; 23(4)2018 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-29662039

RESUMO

Five Schiff bases containing a thiadiazole moiety have been used as poly(vinyl chloride) photostabilizers at low concentrations. The efficiency of Schiff bases as photostabilizers was investigated using various techniques, for example, the changes in poly(vinyl chloride) infrared spectra, molecular weight, chain scission quantum yield, and surface morphology were monitored upon irradiation with an ultraviolet light. Evidently, all the additives used inhibited poly(vinyl chloride) photodegradation at a significant level. The most efficient Schiff base exhibited a high level of aromaticity and contained a hydroxyl group. It seems possible that such photostabilization could be due to the direct absorption of ultraviolet radiation by the additives. In addition, Schiff bases could act as radical scavengers and proton transfer facilitators to stabilize the polymeric materials.


Assuntos
Cloreto de Polivinila/química , Bases de Schiff/química , Tiadiazóis/química , Sequestradores de Radicais Livres/química , Espectrometria de Massas , Fotólise , Espectroscopia de Prótons por Ressonância Magnética , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Raios Ultravioleta , Viscosidade
17.
Sensors (Basel) ; 17(11)2017 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-29099807

RESUMO

Position tracking of pedestrians by means of inertial sensors is a highly explored field of research. In fact, there are already many approaches to implement inertial navigation systems (INSs). However, most of them use a single inertial measurement unit (IMU) attached to the pedestrian's body. Since wearable-devices will be given items in the future, this work explores the implementation of an INS using two wearable-based IMUs. A loosely coupled approach is proposed to combine the outputs of wearable-based INSs. The latter are based on a pocket-mounted IMU and a foot-mounted IMU. The loosely coupled fusion combines the output of the two INSs not only when these outputs are least erroneous, but also automatically favoring the best output. This approach is named smart update. The main challenge is determining the quality of the heading estimation of each INS, which changes every time. In order to address this, a novel concept to determine the quality of the heading estimation is presented. This concept is subject to a patent application. The results show that the position error rate of the loosely coupled fusion is 10 cm/s better than either the foot INS's or pocket INS's error rate in 95% of the cases.

18.
Molecules ; 22(11)2017 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-29143792

RESUMO

Three polyphosphates were used as inhibitors for poly(vinyl chloride) (PVC) photodegradation. The polyphosphates were added to PVC at a concentration of 0.5% by weight. The PVC films (40 µm thickness) were irradiated at room temperature with ultraviolet (UV) light for up to 300 h. The changes in PVC films after irradiation were monitored by Fourier transform infrared spectroscopy, weight loss, viscosity-average molecular weight determination, and atomic force microscopy. These changes were very noticeable in the blank PVC films compared to the ones obtained when additives were used. The polyphosphates can inhibit the PVC photodegradation through direct absorption of UV light, interactions with PVC chains, and acting as radical scavengers.


Assuntos
Fotólise/efeitos dos fármacos , Polifosfatos/farmacologia , Cloreto de Polivinila/química , Microscopia de Força Atômica , Estrutura Molecular , Peso Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Viscosidade
19.
Molecules ; 22(9)2017 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-28891944

RESUMO

Three new tetra-Schiff bases were synthesized and characterized to be used as photostabilizers for poly(vinyl chloride) (PVC) films. The photostability of PVC films (40 µm thickness) in the presence of Schiff bases (0.5 wt %) upon irradiation (300 h) with a UV light (λmax = 365 nm and light intensity = 6.43 × 10-9 ein∙dm-3∙s-1) was examined using various spectroscopic measurements and surface morphology analysis. The changes in various functional groups' indices, weight and viscosity average molecular weight of PVC films were monitored against irradiation time. The additives used showed photostability for PVC films, with Schiff base 1 being the most effective additive upon irradiation, followed by 2 and 3. The atomic force microscopy (AFM) images for the PVC surface containing Schiff base 1 after irradiation were found to be smooth, with a roughness factor (Rq) of 36.8, compared to 132.2 for the PVC (blank). Several possible mechanisms that explain PVC photostabilization upon irradiation in the presence of tetra-Schiff bases were proposed.


Assuntos
Membranas Artificiais , Cloreto de Polivinila/química , Bases de Schiff/síntese química , Microscopia de Força Atômica , Peso Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Raios Ultravioleta
20.
Semin Thromb Hemost ; 42(6): 662-70, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27235831

RESUMO

Patients with atrial fibrillation (AF) who are treated with oral anticoagulants often have concurrent coronary artery disease. Triple oral antithrombotic therapy (TOAT) is often necessity to prevent stent thrombosis or myocardial infarction associated with percutaneous coronary intervention or acute coronary syndrome in patients with comorbid coronary artery disease and AF. Although the use of TOAT (aspirin, clopidogrel, and warfarin) has excellent efficacy against thrombotic complications, this comes on the expense of increased bleeding risk. This review discusses potential strategies to improve TOAT benefit-risk ratio evidence from the literature. These strategies include: (1) dropping aspirin; (2) reducing the duration of TOAT; (3) switching warfarin to a direct oral anticoagulant (DOAC); (4) the use of DOAC in combination with a single antiplatelet agent; and (5) switching clopidogrel to a novel antiplatelet agent. Although dropping aspirin and reducing TOAT duration should be considered in selected AF patients at low risk of thrombosis, the role of DOACs and novel antiplatelets in TOAT has not been thoroughly studied, and there is limited evidence to support their use currently. Ongoing studies will provide safety and efficacy data to guide clinicians who frequently face the challenge of determining the best TOAT combination for their patients.


Assuntos
Síndrome Coronariana Aguda/terapia , Fibrilação Atrial/terapia , Fibrinolíticos/uso terapêutico , Intervenção Coronária Percutânea , Stents , Trombose/prevenção & controle , Síndrome Coronariana Aguda/complicações , Administração Oral , Fibrilação Atrial/complicações , Vasos Coronários/cirurgia , Humanos , Trombose/etiologia
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