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BACKGROUND: Post-operative pain is a common form of acute pain. Objective pain assessment in post-anesthesia care units after surgery is useful regardless of the patient's condition. AIMS: This study aimed to develop and evaluate an acute pain assessment tool for patients in post-anesthesia care units. DESIGN: This was a cross-sectional observational study comprising two stages: scale development and psychometric evaluation. SETTINGS: â¯. PARTICIPANTS/SUBJECTS: â¯. METHODS: Scale items were developed based on a literature review and content validity by experts. The validity and interrater reliability of the pain scale were evaluated using data from 218 patients admitted to the post-anesthesia care unit at a university hospital. A receiver operating characteristic curve was used to identify the sensitivity and specificity for determining the cutoff point for acute pain. RESULTS: We developed an objective acute pain scale, called the APA5, which ranges from 0-10 and comprises behavioral (facial and verbal expressions and body movement) and physiological (changes in heart rate and blood pressure) responses. The APA5 is valid and reliable for assessing acute pain in the recovery room. Sensitivity and specificity were acceptable when the cutoff was 2 out of 10 points. CONCLUSIONS: The APA5 is an easy and simple tool for measuring pain in patients in post-anesthesia care units who have difficulties with self-reporting.
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Dolor Agudo , Anestesia , Humanos , Dolor Agudo/diagnóstico , Dimensión del Dolor , Reproducibilidad de los Resultados , Estudios Transversales , Estudios Observacionales como AsuntoRESUMEN
In this study, two host materials, pCzBzbCz and pCzPybCz, are synthesized to achieve a high efficiency and long lifetime of blue thermally activated delayed fluorescence organic light-emitting diodes (TADF-OLEDs). The molecular design strategy involves the introduction of a pyridine group into the core structure of pCzPybCz as an electron-withdrawing unit, and an electron-donating phenyl group into the structure of pCzBzbCz. These host materials demonstrate good thermal stability and high triplet energy (T1 =3.07â eV for pCzBzbCz and 3.06â eV for pCzPybCz) for the fabrication of blue TADF-OLEDs. In particular, pCzPybCz-based OLED devices demonstrate an external quantum efficiency (EQE) of 22.7 % and an operational lifetime of 24â h (LT90 , time to attain 90 % of initial luminance) at an initial luminance of 1000â cd m-2 . This superior lifetime could be explained by the C-N bond dissociation energy (BDE) in the host molecular structure. Furthermore, a mixed-host system using the electron-deficient 2,4-bis(dibenzo[b,d]furan-2-yl)-6-phenyl-1,3,5-triazine (DDBFT) is proposed to inhibit the formation of the anion state of our host materials. In short, the device operational lifetime is further improved by applying DDBFT. The carbazole-based asymmetric host molecule containing a pyridine core realizes a high-efficiency blue TADF-OLED showing a positive effect on the operating lifetime, and can provide useful strategies for designing new host materials.
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The need for drone traffic control management has emerged as the demand for drones increased. Particularly, in order to control unauthorized drones, the systems to detect and track drones have to be developed. In this paper, we propose the drone position tracking system using multiple Bluetooth low energy (BLE) receivers. The proposed system first estimates the target's location, which consists of the distance and angle, while using the received signal strength indication (RSSI) signals at four BLE receivers and gradually tracks the target based on the estimated distance and angle. We propose two tracking algorithms, depending on the estimation method and also apply the memory process, improving the tracking performance by using stored previous movement information. We evaluate the proposed system's performance in terms of the average number of movements that are required to track and the tracking success rate.
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In this study, lipid extraction from Aurantiochytrium sp. was performed using a molten-salt/ionic-liquid mixture. The total fatty acid content of Aurantiochytrium sp. was 478.8 mg/g cell, from which 145 mg/g cell (30.3% of total fatty acids) of docosahexaenoic acid (DHA) was obtained. FeCl3·6H2O showed a high lipid extraction yield (207.9 mg/g cell), when compared with that of [Emim]OAc, which was only 118.1 mg/g cell; notably however, when FeCl3·6H2O was mixed with [Emim]OAc (5:1, w/w), the yield was increased to 478.6 mg/g cell. When lipid was extracted by the FeCl3·6H2O/[Emim]OAc mixture at a 5:1 (w/w) blending ratio under 90 °C, 30 min reaction conditions, the fatty acid content of the extracted lipid was a high purity 997.7 mg/g lipid, with most of the DHA having been extracted (30.2% of total fatty acids). Overall, lipid extraction from Aurantiochytrium sp. was enhanced by the synergistic effects of the molten-salt/ionic-liquid mixture with different ions.
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Ácidos Docosahexaenoicos/análisis , Lípidos/aislamiento & purificación , Estramenopilos/química , Bioingeniería , Biocombustibles , Cloruros , Ácidos Grasos/análisis , Compuestos Férricos , Microbiología de Alimentos , Imidazoles , Iones , Microalgas/química , SolventesRESUMEN
Introduction: In targeted enzyme prodrug constructs, it is critical to control the bioactivity of the drug in its prodrug form. The preparation of such constructs often involves conjugation reactions directed to functional groups on amino acid side chains of the protein, which result in random conjugation and incomplete control of bioactivity of a prodrug, which may result in significant nontarget effect. Thus, more specific method of modification is desired. If the drug is a glycoprotein, enzymatic oxidation may offer an alternative approach for therapeutic glycoproteins. Methods: Tissue plasminogen activator (tPA), a model glycoprotein enzyme, was treated with galactose oxidase (GO) and horseradish peroxidase, followed by thiolation reaction and conjugation with low molecular weight heparin (LMWH). The LMWH-tPA conjugate was isolated by ion-exchange chromatography followed by centrifugal filtration. The conjugate was characterized for its fibrinolytic activity and for its plasminogen activation through an indirect amidolytic assay with a plasmin-specific substrate S-2251 when LMWH-tPA conjugate is complexed with protamine-albumin conjugate, followed by triggered activation in the presence of heparin. Results: LMWH-tPA conjugate prepared via enzymatic oxidation retained ~95% of its fibrinolytic activity with respect to native tPA. Upon complexation with protamine-albumin conjugate, the activity of LMWH-tPA was effectively inhibited (~90%) whereas the LMWH-tPA prepared by random thiolation exhibited ~55% inhibition. Addition of heparin fully generated the activities of both conjugates. Conclusion: The tPA was successfully modified via enzymatic oxidation by GO, resulting in enhanced control of its activity in the prodrug construct. This approach can be applied to other therapeutic glycoproteins.
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The feasibilities of cell disruption by homogenization-assisted high-pressure nano-dispersion and recovery of astaxanthin-containing oil by oil partitioning in oil-acetone-water solution were examined. The total fatty acid content of Haematococcus pluvialis was 414.6 mg/g cell, and the astaxanthin content was 4.4% of oil. Extra oil was added to the solution in order to recover oil through instability of dispersion status instead of solvent evaporation. A total amount of energy of 0.34 kWh/L was consumed for acetone evaporation at 50 °C, whereas fully 1.86 kWh/L of energy for water evaporation was consumed. When soybean oil was added to the solution after partial acetone evaporation, the oil-recovery yield was 97.8%, while the yield after full evaporation was 97.6% in 10-g/L solution. However, the energy consumed for partial evaporation (0.29 kWh/L) was much lower than that for full evaporation (0.40 kWh/L). When H. pluvialis oil was added to the solution after partial evaporation, the oil-recovery yield decreased to 90.6% due to the impurity of crude H. pluvialis oil in 10-g/L solution. Methods such as refining of H. pluvialis oil, increase of microalgae dosage for cell disruption, and increase of the injection amount of extra oil can help to enhance oil recovery.
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Biotecnología/métodos , Chlorophyceae/metabolismo , Ácidos Grasos/química , Aceites/análisis , Acetona/análisis , Pared Celular , Chlorophyta , Cromatografía de Gases , Cromatografía Liquida , Microalgas , Solubilidad , Glycine max , Temperatura , Agua/análisis , Xantófilas/análisisRESUMEN
Improving the content and production of high-value ketocarotenoid pigments is critical for the commercialization of microalgal biorefineries. This study reported the use of magnesium aminoclay (MgAC) nanoparticles for enhancement of astaxanthin production by Haematococcus pluvialis in photoautotrophic cultures. Addition of 1.0 g/L MgAC significantly promoted cellular astaxanthin biosynthesis (302 ± 69 pg/cell), presumably by inducing tolerable oxidative stress, corresponding to a 13.7-fold higher production compared to that in the MgAC-untreated control (22 ± 2 pg/cell). The lipid content and cell size of H. pluvialis improved by 13.6- and 2.1-fold, respectively, compared to that of the control. Despite reduced cell numbers, the overall astaxanthin production (10.3 ± 0.4 mg/L) improved by 40% compared to the control (7.3 ± 0.6 mg/L), owing to improved biomass production. However, an MgAC dosage above 1.0 g/L inhibited biomass production by inducing electrostatic cell wall destabilization and aggregation. Therefore, MgAC-induced stimulation of algae varies widely based on their morphological and physiological characteristics.
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Microalgas , Nanopartículas , Magnesio , XantófilasRESUMEN
In this study, we aimed to demonstrate the feasibility of the application of biocompatible liquid type fluorescent carbon nanodots (C-paints) to microalgae by improving microalgae productivity. C-paints were prepared by a simple process of ultrasound irradiation using polyethylene glycol (PEG) as a passivation agent. The resulting C-paints exhibited a carbonyl-rich surface with good uniformity of particle size, excellent water solubility, photo-stability, fluorescence efficiency, and good biocompatibility (<10.0 mg mL-1 of C-paints concentration). In the practical application of C-paints to microalgae culture, the most effective and optimized condition leading to growth promoting effect was observed at a C-paints concentration of 1.0 mg mL-1 (>20% higher than the control cell content). A C-paints concentration of 1-10.0 mg mL-1 induced an approximately >1.8 times higher astaxanthin content than the control cells. The high light delivery effect of non-cytotoxic C-paints was applied as a stress condition for H. pluvialis growth and was found to play a major role in enhancing productivity. Notably, the results from this study are an essential approach to improve astaxanthin production, which can be used in various applications because of its therapeutic effects such as cancer prevention, anti-inflammation, immune stimulation, and treatment of muscle-soreness.
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Antioxidantes/química , Carbono/química , Animales , Humanos , Microalgas/efectos de los fármacos , Espectroscopía de Fotoelectrones , Espectroscopía Infrarroja por Transformada de Fourier , Xantófilas/química , Xantófilas/farmacologíaRESUMEN
In this work, a new stress-based method for rapid induction of triacylglycerol (TAG) and total and polyunsaturated fatty acid accumulations in Chlorella sp. by mild electric stimulation is presented. When a cathodic current of 31â¯mA (voltage: 4â¯V) was applied to the algal cells for 4â¯h, the TAG content of the electro-treated cells was sharply increased to a level 2.1 times that of the untreated control. The contents of the polyunsaturated linoleic (C18:2n6) and linolenic (C18:3n3) acids in the electro-treated cells were also 36 and 57% higher than those in the untreated cells, respectively. Cyclic voltammetry and various biochemical analyses indicate that TAG and fatty acid formations are electro-stimulated via de novo fatty acid biosynthesis and metabolic transformation in the Chlorella cells.
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Chlorella , Estimulación Eléctrica , Ácidos Grasos , Ácidos Grasos Insaturados , Lípidos , TriglicéridosRESUMEN
Energy-saving, high-efficiency cell disruption is a critical step for recovery of thermolabile antioxidant astaxanthin from Haematococcus pluvialis cyst cells of rigid cell-wall structure. In this study, as room-temperature green solvents, 10 types of 1-ethyl-3-methylimidazolium ([Emim])-based ionic liquids (ILs) were compared and evaluated for their abilities to disrupt H. pluvialis cyst cells for astaxanthin/lipid extraction. Among the 10 ILs tested, 3 [Emim]-based ILs with HSO4, CH3SO3, and (CF3SO2)2N anions were selected based on astaxanthin/lipid extraction performance and synthesis cost. When pretreated with IL/water mixtures, intact cyst cells were significantly torn, broken or shown to release cytoplasmic components, thereby facilitating subsequent separation of astaxanthin/lipid by hexane. However, excess IL pretreatments at high temperature/IL dosages and longer incubation times significantly deteriorated lipid and/or astaxanthin. Under optimized mild conditions (6.7% (v/v) IL in water solution, 30⯰C, 60â¯min), almost complete astaxanthin recoveries (>99%) along with moderate lipid extractions (â¼82%) could be obtained.
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Chlorophyceae/metabolismo , Líquidos Iónicos/química , Iones , Lípidos/química , Temperatura , Agua/química , Xantófilas/química , Xantófilas/metabolismoRESUMEN
A new side-chain polymer (X-TPACz) bearing hole-transporting pendant groups accompanying a thermally crosslinkable entity was synthesized using N-([1,1'-biphenyl]-4-yl)- N-(4-(9-(4-vinylbenzyl)-9 H-carbazol-3-yl)phenyl)bicyclo[4.2.0]octa-1(6),2,4-trien-3-amine (6) via addition polymerization. The X-TPACz could be spontaneously crosslinked without using any further reagents and showed a good film-forming property upon low-temperature thermal treatment. The thermal curing temperature for the X-TPACz film was optimized to be 180 °C based on a differential scanning calorimetry thermogram. Moreover, the thermal degradation temperature of X-TPACz measured to be over 467 °C using thermogravimetric analysis demonstrated that it shows excellent thermal stability. In particular, X-TPACz exhibits the highest occupied molecular orbital (HOMO) energy level to be -5.26 eV, which is beneficial for facile hole injection and transportation. Consequently, the thermally activated delayed fluorescence organic light-emitting diodes fabricated using X-TPACz as the hole-transporting material showed state-of-the-art performances with a low turn-on voltage ( Von) of only 2.7 V and a high external quantum efficiency (EQE) of 19.18% with a high current efficiency (CE) of 66.88 cd/A and a high power efficiency (PE) of 60.03 lm/W, which are highly superior to those of the familiar poly(9-vinylcarbazole) (PVK)-based devices ( Von = 3.9 V, EQE of 17.42%, with CE of 58.33 cd/A and PE of 33.32 lm/W). The extremely low turn-on voltage and high EQE were found to be due to the higher-lying highest occupied molecular orbital energy level ( EHOMO = -5.23 eV) and better hole-transporting property of X-TPACz than those of PVK.
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In this work, three-armed luminogens IAcTr-out and IAcTr-in were synthesized and used as emitters bearing triazine and indenoacridine moieties in thermally activated delayed fluorescence organic light-emitting diodes (OLEDs). These molecules could form a uniform thin film via the solution process and also allowed the subsequent deposition of an electron transporting layer either by vacuum deposition or by an all-solution coating method. Intriguingly, the new luminogens displayed aggregation-induced emission (AIE), which is a unique photophysical phenomenon. As a nondoped emitting layer (EML), IAcTr-in showed external quantum efficiencies (EQEs) of 11.8% for the hybrid-solution processed OLED and 10.9% for the all-solution processed OLED with a low efficiency roll-off. This was evident by the higher photoluminescence quantum yield and higher rate constant of reverse intersystem crossing of IAcTr-in, as compared to IAcTr-out. These AIE luminogens were used as dopants and mixed with the well-known host material 1,3-bis( N-carbazolyl)benzene (mCP) to produce a high-efficiency OLED with a two-component EML. The maximum EQE of 17.5% was obtained when using EML with IAcTr-out doping (25 wt %) into mCP, and the OLED with EML bearing IAcTr-in and mCP showed a higher maximum EQE of 18.4% as in the case of the nondoped EML-based device.
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Dynamic filtration equipped with a perforated disk was adopted for the first time to dewater and concentrate Tetraselmis suecica, from a typical solution of 2-100â g/L of dense biomass suited for the downstream process. An ultrafiltration membrane, polyethersulfone 150â kDa, was found to best perform in terms of high biomass retention and filtration rate. At 1600â rpm, the highest rotation speed of the disk we tested, plateau permeate flux increased up to 20.2 times higher than those with no rotation; this improvement was attributed to fouling reduction (up to 98%) via distinctively high-shear stress on the membrane surface. Even at a high biomass concentration (100â g/L) where fouling formation was very serious, the heightened shear stress caused high flux to be maintained and fouling resistance to be reduced in an effective way. When trans-membrane pressure was increased in a stepwise manner, flux continuously rose at high rotation speed; at low speed, on the other hand, the limiting flux was observed. The dynamic filtration with the perforated disk, which was an effective high-shear stress generator, was proven to be a promising dewatering means of T. suecica, and especially so for the production of highly concentrated biomass.
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Incrustaciones Biológicas/prevención & control , Chlorophyta , Polímeros/química , Sulfonas/química , Ultrafiltración , Purificación del Agua/métodos , Biomasa , MicroalgasRESUMEN
New M- and V-shaped perylene diimide (PDI)-based small molecules using a non-conjugated 1,1-diphenylcyclohexane linker (CP-M and CP-V, respectively) were designed and synthesized as new n-type acceptors for nonfullerene-based polymer solar cells. The blended film with poly[(2,5-bis(2-hexyldecyloxy)phenylene)-alt-(5,6-difluoro-4,7-di(thiophen-2-yl)benzo[c][1,2,5]thiadiazole)] (PPDT2FBT) and CP-V displayed a higher power conversion efficiency of 5.28% due to higher short circuit current and fill factor values.
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In this study, a simultaneous process of harvesting biomass and extracting crude bio-oil was attempted from wet microalgae biomass using FeCl3 and Fe2(SO4)3 as both coagulant and cell-disrupting agent. A culture solution of Chlorella sp. KR-1 was firstly concentrated to 20 g/L and then proceeded for cell disruption with the addition of H2O2. Optimal dosage were 560 and 1060 mg/L for FeCl3 and Fe2(SO4)3, showing harvesting efficiencies of more than 99%. Optimal extraction conditions were identified via the response surface method (RSM), and the extraction yield was almost the same at 120 °C for both iron salts but FAME compositions after transesterification was found to be quite different. Given iron salts were a reference coagulant in water treatment in general and microalgae harvesting in particular, the present approach of using it for harvesting and oil-extraction in a simultaneous manner can serve as a practical route for the microalgae-derived biodiesel production.
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Compuestos Férricos/química , Microalgas/aislamiento & purificación , Lípidos/aislamiento & purificación , Microalgas/citologíaRESUMEN
In this study, hydrothermal acid treatment for efficient recovery of sugar from Golenkinia sp. was investigated. The initial glucose and XMG (xylose, mannose, and galactose) contents of a prepared Golenkinia sp. solution (40g/L) were 15.05 and 5.24g/L, respectively. The microalgal cell walls were hydrolyzed, for sugar recovery, by enzymatic saccharification and/or hydrothermal acid treatment. Among the various hydrothermal acid treatment conditions, the most optimal were the 2.0% H2SO4 concentration at 150°C for 15min, under which the glucose- and XMG-extraction yields were 71.7% and 64.9%, respectively. By pH 4.8, 50°C enzymatic hydrolysis after optimal hydrothermal acid treatment, the glucose- and XMG-extraction yields were additionally increased by 8.3% and 0.8%, respectively. After hydrothermal acid treatment, the combination with the enzymatic hydrolysis process improved the total sugar yield of Golenkinia sp. to 75.4%.
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Carbohidratos/aislamiento & purificación , Chlorophyta/química , Etanol/aislamiento & purificación , Microalgas/química , Ácidos Sulfúricos/química , Agua/química , Carbohidratos/química , Fraccionamiento Celular , Celulasa/química , Etanol/química , Calor , Hidrólisis , beta-Glucosidasa/químicaRESUMEN
A well-defined, one-to-one conjugate between human serum albumin (HSA) and protamine was synthesized and characterized as a biocompatible carrier for macromolecules. In circulation, the conjugate will camouflage drug molecules upon complex formation, while liberating free drug at the desired location using a triggering mechanism. The N-terminus of protamine was thiolated and conjugated with the unpaired Cysteine-34 of HSA, and was purified by ion-exchange chromatography. The molecular weight of the conjugate was 70.8 kDa, confirming one-to-one conjugation between HSA (66.6 KDa) and protamine (4200 Da). Superimposed fluorescence spectra of native HSA and HSA-protamine conjugate indicated no conformational change around the Trp-214. The conjugate had marked reduction in hemolytic and cytotoxic properties compared to protamine. When therapeutic potential was tested using tissue plasminogen activator as a model drug, HSA-protamine conjugate suppressed the enzymatic activity by 65%, which was fully recovered by a triggering agent, heparin. The construct showed binding characteristics with activated platelets upon conjugation with a targeting peptide, demonstrating flexibility to introduce suitable homing moiety on the surface. The camouflaged construct retained triggered release property in human plasma condition. Overall, the conjugate has a good potential to serve as a biocompatible platform for macromolecular drugs.
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Materiales Biocompatibles/química , Sistemas de Liberación de Medicamentos , Sustancias Macromoleculares/administración & dosificación , Protaminas/química , Albúmina Sérica/química , Activador de Tejido Plasminógeno/administración & dosificación , Cromatografía por Intercambio Iónico , Heparina/farmacología , Humanos , Sustancias Macromoleculares/farmacología , Sustancias Macromoleculares/uso terapéutico , Péptidos/metabolismo , Activación Plaquetaria , Estabilidad Proteica , Espectrometría de Masa por Ionización de Electrospray , Compuestos de Sulfhidrilo/metabolismo , Activador de Tejido Plasminógeno/química , Activador de Tejido Plasminógeno/metabolismo , Activador de Tejido Plasminógeno/farmacologíaRESUMEN
In this study, nitric acid (HNO3) was evaluated as an acid catalyst for rice straw pretreatment, and, after neutralization, as a sole nitrogen source for subsequent fermentation. Response surface methodology was used to obtain optimal pretreatment condition with respect to HNO3 concentration (0.2-1.0%), temperature (120-160 °C) and reaction time (1-20 min). In a condition of 0.65% HNO3, 158.8 °C and 5.86 min, a maximum xylose yield of 86.5% and an enzymatic digestibility of 83.0% were achieved. The sugar solution that contained nitrate derived from the acid catalyst supported the enhancement of ethanol yield by Pichia stipitis from 10.92 g/L to 14.50 g/L. The results clearly reveal that nitric acid could be used not only as a pretreatment catalyst, but also as a nitrogen source in the fermentation process for bioethanol production. It is anticipated that the HNO3-based pretreatment can reduce financial burden on the cellulosic bioethanol industry by simplifying after-pretreatment-steps as well as providing a nitrogen source.
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Etanol/metabolismo , Ácido Nítrico/química , Nitrógeno/metabolismo , Oryza/química , Pichia/metabolismo , Tallos de la Planta/química , Catálisis , Análisis Factorial , Fermentación , Hidrólisis , Lignina/metabolismo , Ácido Nítrico/metabolismo , Residuos , Xilosa/biosíntesisRESUMEN
Microalgal lipid with a high free fatty acid (FFA) content was directly extracted from Chlorella vulgaris, using SDBS, in an acid-catalyzed hot-water extraction process. The total fatty acid content of C. vulgaris was 296.0 mg/g cell. Under the 1.0% sulfuric acid, 0.4% SDBS conditions, the FFA content of the lipid increased to 96.7%, and the lipid-extraction yield was 248.4 mg/g cell. Under the 2.0% sulfuric acid, 0.2% SDBS conditions, the FFA content of the lipid was 96.1%, and the lipid-extraction yield was 266.0mg/g cell. Whereas the FAME content of the microalgal lipid extracted by hexane-methanol was 76.4% at the 10.0% sulfuric acid concentration, the FAME content of the high-FFA microalgal lipid was increased to 70.1% at a sulfuric acid concentration of only 0.1%. By combined sulfuric acid/SDBS treatment, high-FFA microalgal lipid was extracted in large yields; moreover, the amount of catalyst was remarkably reduced in the esterification of FFA.
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Biocombustibles , Chlorella vulgaris/química , Ácidos Grasos no Esterificados/aislamiento & purificación , Microalgas/química , Tensoactivos/química , Catálisis , Lípidos/químicaRESUMEN
Hydrothermal acid (combined with autoclaving and nitric acid) pretreatment was applied to Nannochloropsis salina as a cost-effective yet efficient way of lipid extraction from wet biomass. The optimal conditions for this pretreatment were determined using a statistical approach, and the roles of nitric acid were also determined. The maximum lipid yield (predicted: 24.6%; experimental: 24.4%) was obtained using 0.57% nitric acid at 120°C for 30min through response surface methodology. A relatively lower lipid yield (18.4%) was obtained using 2% nitric acid; however, chlorophyll and unsaturated fatty acids, both of which adversely affect the refinery and oxidative stability of biodiesel, were found to be not co-extracted. Considering its comparable extractability even from wet biomass and ability to reduce chlorophyll and unsaturated fatty acids, the hydrothermal nitric acid pretreatment can serve as one direct and promising route of extracting microalgae oil.