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Flooding is a major natural hazard worldwide, causing catastrophic damage to communities and infrastructure. Due to climate change exacerbating extreme weather events robust flood hazard modeling is crucial to support disaster resilience and adaptation. This study uses multi-sourced geospatial datasets to develop an advanced machine learning framework for flood hazard assessment in the Arambag region of West Bengal, India. The flood inventory was constructed through Sentinel-1 SAR analysis and global flood databases. Fifteen flood conditioning factors related to topography, land cover, soil, rainfall, proximity, and demographics were incorporated. Rigorous training and testing of diverse machine learning models, including RF, AdaBoost, rFerns, XGB, DeepBoost, GBM, SDA, BAM, monmlp, and MARS algorithms, were undertaken for categorical flood hazard mapping. Model optimization was achieved through statistical feature selection techniques. Accuracy metrics and advanced model interpretability methods like SHAP and Boruta were implemented to evaluate predictive performance. According to the area under the receiver operating characteristic curve (AUC), the prediction accuracy of the models performed was around > 80%. RF achieves an AUC of 0.847 at resampling factor 5, indicating strong discriminative performance. AdaBoost also consistently exhibits good discriminative ability, with AUC values of 0.839 at resampling factor 10. Boruta and SHAP analysis indicated precipitation and elevation as factors most significantly contributing to flood hazard assessment in the study area. Most of the machine learning models pointed out southern portions of the study area as highly susceptible areas. On average, from 17.2 to 18.6% of the study area is highly susceptible to flood hazards. In the feature selection analysis, various nature-inspired algorithms identified the selected input parameters for flood hazard assessment, i.e., elevation, precipitation, distance to rivers, TWI, geomorphology, lithology, TRI, slope, soil type, curvature, NDVI, distance to roads, and gMIS. As per the Boruta and SHAP analyses, it was found that elevation, precipitation, and distance to rivers play the most crucial roles in the decision-making process for flood hazard assessment. The results indicated that the majority of the building footprints (15.27%) are at high and very high risk, followed by those at very low risk (43.80%), low risk (24.30%), and moderate risk (16.63%). Similarly, the cropland area affected by flooding in this region is categorized into five risk classes: very high (16.85%), high (17.28%), moderate (16.07%), low (16.51%), and very low (33.29%). However, this interdisciplinary study contributes significantly towards hydraulic and hydrological modeling for flood hazard management.
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Inundaciones , Aprendizaje Automático , India , Medición de Riesgo , Análisis de Datos , AlgoritmosRESUMEN
N-methyl-D-aspartate (NMDA) receptors, i.e., inotropic glutamate receptors, are important in synaptic plasticity, brain growth, memory, and learning. The activation of NMDA is done by neurotransmitter glutamate and co-agonist (glycine or D-serine) binding. However, the over-activation of NMDA elevates the intracellular calcium influx, which causes various neurological diseases and disorders. Therefore, to prevent excitotoxicity and neuronal death, inhibition of NMDA must be done using its antagonist. This review delineates the structure of subunits of NMDA and the conformational changes induced after the binding of agonists (glycine and D-serine) and antagonists (ifenprodil, etc.). Additionally, reported NMDA antagonists from different sources, such as synthetic, semisynthetic, and natural resources, are explained by their mechanism of action and pharmacological role. The comprehensive report also addresses the chemical spacing of NMDA inhibitors and in-vivo and in-vitro models to test NMDA antagonists. Since the Blood-Brain Barrier (BBB) is the primary membrane that prevents the penetration of a wide variety of drug molecules, we also elaborate on the medicinal chemistry approach to improve the effectiveness of their antagonists.
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Receptores de N-Metil-D-Aspartato , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Receptores de N-Metil-D-Aspartato/metabolismo , Humanos , Animales , Química Farmacéutica , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/efectos de los fármacosRESUMEN
INTRODUCTION: Psoriasis is a chronic, inflammatory, non-communicable skin disorder that affects a patient's social and emotional well-being. It is characterized by hyperproliferation of keratinocytes, irregular shedding of skin cells, and abnormal invasion of inflammatory mediators. The treatment strategy is designed based on the severity of the disease condition starting from topical, phototherapy, systemic, and biologics. In recent years, extensive research into the underlying mechanisms of psoriasis has led to significant advancement in treatment options from small molecules to biologics. AREA COVERED: This review focuses on intracellular and molecular mechanisms such as AhR, A3AR, RIP1, CGRP, and S1P that serve as novel pharmacological targets for psoriasis. Moreover, new molecules are approved or are under clinical investigation to interfere with these target mechanisms. EXPERT OPINION: A detailed understanding of signaling pathways provides potential targets and molecular mechanisms for the inflammatory cascade in psoriasis. This has led to the development of small molecules targeting specific pathways. Further, the combination of nanotechnology can assist in dose reduction leading to reduced adverse effects in the management of psoriasis.
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Productos Biológicos , Psoriasis , Humanos , Psoriasis/tratamiento farmacológico , Psoriasis/metabolismo , Piel/metabolismo , Productos Biológicos/metabolismo , Productos Biológicos/farmacología , Productos Biológicos/uso terapéuticoRESUMEN
Curcumin loaded solid lipid nanoparticles (CSLNs) and probiotic (Lactobacillus plantarum UBLP-40; L. plantarum) were currently co-incorporated into a wound dressing. The combination with manifold anti-inflammatory, anti-infective, analgesic, and antioxidant properties of both curcumin and L. plantarum will better manage complex healing process. Recent reports indicate that polyphenolics like curcumin improve probiotic effects. Curcumin was nanoencapsulated (CSLNs) to improve its bioprofile and achieve controlled release on the wound bed. Bacteriotherapy (probiotic) is established to promote wound healing via antimicrobial activity, inhibition of pathogenic toxins, immunomodulation, and anti-inflammatory actions. Combination of CSLNs with probiotic enhanced (560%) its antimicrobial effects against planktonic cells and biofilms of skin pathogen, Staphylococcus aureus 9144. The sterile dressing was devised with selected polymers, and optimized for polymer concentration, and dressing characteristics using a central composite design. It exhibited a swelling ratio of 412 ± 36%, in vitro degradation time of 3 h, optimal water vapor transmission rate of 1516.81 ± 155.25 g/m2/day, high tensile strength, low-blood clotting index, case II transport, and controlled release of curcumin. XRD indicated strong interaction between employed polymers. FESEM revealed a porous sponge like meshwork embedded with L. plantarum and CSLNs. It degraded and released L. plantarum, which germinated in the wound bed. The sponge was stable under refrigerated conditions for up to six months. No translocation of probiotic from wound to the internal organs confirmed safety. The dressing exhibited faster wound closure and lowered bioburden in the wound area in mice. This was coupled with a decrease in TNF-α, MMP-9, and LPO levels; and an increase in VEGF, TGF-ß, and antioxidant enzymes such as catalase and GSH, establishing multiple healing pathways. Results were compared with CSLNs and probiotic-alone dressings. The dressing was as effective as the silver nanoparticle-based marketed hydrogel dressing; however, the cost and risk of developing resistance would be much lower currently.
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Antiinfecciosos , Curcumina , Lactobacillus plantarum , Nanopartículas del Metal , Ratones , Animales , Curcumina/farmacología , Antioxidantes/farmacología , Preparaciones de Acción Retardada/farmacología , Plata/farmacología , Cicatrización de Heridas , Vendajes , Antiinfecciosos/farmacología , Antiinflamatorios no Esteroideos/farmacología , Polímeros/farmacología , Antibacterianos/farmacologíaRESUMEN
The therapeutic potential of atazanavir (BCS Class II drug), a highly selective inhibitor of human immunodeficiency virus (HIV-1), has been largely limited due to its low intrinsic solubility at elevated pH resulting in low oral bioavailability. Thus, the current work describes the systematic development, optimization, and evaluation of hydroxypropyl methylcellulose acetate succinate (HPMC-AS)-based supersaturable preconcentrate isotropic mixture (SP-IM) containing long-chain triglyceride to improve intestinal lymphatic transport and augment oral bioavailability of atazanavir (ATZ). A D-optimal mixture design was employed for optimization of plain IM containing corn oil, oleic acid, Tween 80, and propylene glycol, evaluating various critical quality attributes (CQAs) like particle size, polydispersity index, self-emulsification time, % transmittance, and drug content. In silico analysis and in vitro supersaturation test facilitated the selection of HPMC-AS as a best suited polymeric precipitation inhibitor (PPI) for formulating ATZ loaded SP-IM (ATZ-SP-IM). In vitro dissolution data indicated that ATZ-SP-IM exhibits superior performance in 0.025 N HCl and pH 6.8 over pure drug. Ex vivo permeation and in vivo pharmacokinetic study of ATZ-SP-IM corroborated enhanced permeation (2.03 fold) and improved drug absorption via lymphatic transport in Wistar rats. Further, the pharmacokinetic performance of ATZ-SP-IM was not affected in presence of H2 receptor antagonist. Therefore, the results showed that ATZ-SP-IM can significantly improve the biopharmaceutical attributes of ATZ so as to lay a foundation of further research on the new dosage form of ATZ.
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Sulfato de Atazanavir , Antagonistas de los Receptores H2 de la Histamina , Animales , Ratas , Sulfato de Atazanavir/farmacología , Productos Biológicos/farmacología , Ratas Wistar , Antagonistas de los Receptores H2 de la Histamina/farmacologíaRESUMEN
The study aimed to increase the intestinal solubility and absorption of orally bioavailable clopidogrel-bisulfate (CPB) by complexing with hydroxypropyl-ß-cyclodextrin (HCD) to form a binary inclusion complex that was stabilized by Tween 80 (T80) resulting into mixed inclusion complex. The results of phase solubility studies and molecular docking of CPB with ß-cyclodextrin (ß-CD) and HCD suggested higher solubility and binding energy of the stable CPB: HCD complex in the presence of T80 as compared to the CPB: ß-CD complex. The D-Optimal mixture design was used to optimize the formulation containing the CPB: HCD: T80 mixed inclusion complex. The results suggest the enhanced stability of the CPB: HCD inclusion complex in the presence of T80. The spectral attributes confirmed the inclusion complexation and pointed out the central position of CPB in a hydrophilic cavity of HCD. Further, the prepared soft gelatin capsule successfully confirmed the importance of obliterating the intestinal precipitation associated problem of CPB through an in-vitro release study. The anticoagulant activity in rabbits confirmed that soft gelatin capsules showed 1.2 folds and 1.3 folds increase in clotting time, 1.2 fold and 1.5 folds increase in bleeding time when compared to marketed formulation and pure drug, respectively. Conclusively, soft gelatin capsules exhibit the potential to enhance the oral bioavailability of CPB, leading to reduction of the dose and dose-related side effects.
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Gelatina , Animales , Conejos , 2-Hidroxipropil-beta-Ciclodextrina/química , Solubilidad , Clopidogrel , Simulación del Acoplamiento Molecular , Rastreo Diferencial de Calorimetría , CápsulasRESUMEN
This study investigates the development of atazanavir-concentrate loaded soft gelatin capsule for achieving enhanced atazanavir (ATV) concentration in plasma, brain, spleen, and lymphatics beneficial in the significant reduction of viral load in HIV infection. For this purpose, ATV-concentrate in the presence and absence of Soluplus with corn oil, oleic acid, tween 80, and propylene glycol was developed. The developed ATV-concentrate was found to have enhanced dispersibility with no signs of precipitation after dilution with simulated G.I fluid as evident from particle size (16.49±0.32 nm) and PDI (0.217±0.02) analysis. The rheological and molecular docking studies explainedthe reduction of viscosity of SuATV-C due to the intermolecular H-bond between ATV and Soluplus that helps to retard crystallization. The shell of the soft gelatin capsule retains its integrity when subjected to a folding endurance test on a texture analyzer depicting that the concentrate did not affect the integrity of the soft gelatin capsule shell. An ex vivo and in vivo pharmacokinetic study in rats revealed that the SuATV-C soft gelatin capsule (SuATV-C SGC) indicated 2.9 fold improvement in rate and extent of permeation and absorption than that of ATV-suspension. The tissue distribution study also exhibited higher drug concentration in the brain (2.5 fold), lymph nodes (2.7 fold), and spleen (1.2 fold) administered with SuATV-C SGC, revealing the overwhelming influence of Soluplus and corn oil. In a nutshell, these studies demonstrated that SuATV-C SGC seems to have the potential to deliver an anti-retroviral drug to the viral sanctuaries for the better management of HIV.
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Fármacos Anti-VIH , Infecciones por VIH , Animales , Fármacos Anti-VIH/farmacocinética , Sulfato de Atazanavir/farmacocinética , Sulfato de Atazanavir/uso terapéutico , Encéfalo , Aceite de Maíz/uso terapéutico , Gelatina , Infecciones por VIH/tratamiento farmacológico , Simulación del Acoplamiento Molecular , Ácido Oléico , Polietilenglicoles , Polisorbatos , Polivinilos , Glicoles de Propileno , Ratas , BazoRESUMEN
A code blue event is an emergency code to indicate when a patient goes into cardiac arrest and needs resuscitation. In this paper, we model the binary response of a intensive care unit (ICU) patients experiencing a code-blue event, starting with vital time-series data of patients in 12 ICU beds. Our study introduces day-of and day-ahead risk scoring models trained against ground truth information on per-patient-per-day code-blue events, starting with multi-variate vital-time-series-sequences of varying durations with a plurality of engineered features capturing temporal variations of these signals. Actionable events, including code-blue events, aggregated by patient by day were predicted on the day-of or day-ahead with an overall accuracy of over 80% in our best models. Such models have potential to improve healthcare delivery by providing just-in-time alerting, enabling proactive and preventative clinical interventions, through continuous patient monitoring.
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Reanimación Cardiopulmonar , Alarmas Clínicas , Paro Cardíaco , Monitoreo Fisiológico , Cuidados Críticos , Paro Cardíaco/terapia , Humanos , Factores de TiempoRESUMEN
In present work, a film forming gel (FFG) was developed through ingenious amalgamation of polymers: Pullulan, Terminalia catappa and Carbopol®971P ® for cutaneous delivery of clotrimazole (CTZ) employing D-optimal mixture design. The developed FFG possess pseudoplastic, viscoelastic, thixotropic characteristics leading to good spreadability (35.71 ± 1.72 g·s, work of shear; 452.73 ± 8.23 g, firmness). Upon solvent evaporation, FFG converted in situ into bioadhesive film (81.90 ± 3.24 g) leading to longer residence on skin surface, prolonged delivery and ~1.3 fold enhanced CTZ skin retention as compare to commercial cream as evident from biopharmaceutical analysis, which is ideal for skin infections treatment. The simulation analysis suggested ≥10 µg/mL (MIC against C. albicans) CTZ concentration maintained for 2 times the days in rat skin as well as human skin as compared to commercial cream. Overall, the developed FFG system ascertained to be promising delivery system for treatment of chronic skin conditions.
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Productos Biológicos/química , Productos Biológicos/farmacología , Geles/química , Geles/farmacología , Glucanos/química , Glucanos/farmacología , Terminalia/química , Animales , Femenino , Humanos , Masculino , Ratas , Reología , Piel/efectos de los fármacos , ViscosidadRESUMEN
Resistive switching (RS) devices are emerging electronic components that could have applications in multiple types of integrated circuits, including electronic memories, true random number generators, radiofrequency switches, neuromorphic vision sensors, and artificial neural networks. The main factor hindering the massive employment of RS devices in commercial circuits is related to variability and reliability issues, which are usually evaluated through switching endurance tests. However, we note that most studies that claimed high endurances >106 cycles were based on resistance versus cycle plots that contain very few data points (in many cases even <20), and which are collected in only one device. We recommend not to use such a characterization method because it is highly inaccurate and unreliable (i.e., it cannot reliably demonstrate that the device effectively switches in every cycle and it ignores cycle-to-cycle and device-to-device variability). This has created a blurry vision of the real performance of RS devices and in many cases has exaggerated their potential. This article proposes and describes a method for the correct characterization of switching endurance in RS devices; this method aims to construct endurance plots showing one data point per cycle and resistive state and combine data from multiple devices. Adopting this recommended method should result in more reliable literature in the field of RS technologies, which should accelerate their integration in commercial products.
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BACKGROUND: Varicella-Zoster virus (VZV) infection in healthcare organizations, especially in intensive care units (ICU), having admitted immunocompromised patients, is of serious concern as well as poses threat to healthcare workers working in such critical areas. The present report defines the transmission and infection control measures initiated to curtail VZV infection spread in the trauma ICU of a tertiary care hospital of North India. OUTBREAK REPORT: At the infection outset, there were 12 patients admitted in ICU and 54 healthcare workers were posted to manage these critical patients. After confirmation of VZV infection, all susceptible patients as well as healthcare workers were quarantined and fresh intake of patients was restricted. Out of the total healthcare workers, 14 (25.92%) were found susceptible (as per protective VZV IgG titers) and were vaccinated. Of the 12 patients admitted in the ICU, six patients were discharged and sent home directly, four patients expired due to their critical disease state, one patient left against medical advice, and one patient remained admitted in ICU till the incubation period was over. Epidemiologically, line listing for index case reporting was done. The efficacy of control measures was re-evaluated to strengthen existing infection control practices and general measures viz. strict hand washing, adherence to aseptic protocols and intensification of environmental cleaning. CONCLUSIONS: Established varicella surveillance measures ensure VZV outbreaks are identified in a timely manner and control measures implemented to prevent further transmission. Also, vaccination policy among HCWs is the utmost requirement despite having huge financial implications.
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Carbamoylethyl pullulan-grafted palmitic acid (CP-g-PA), a novel self-assembled polymer was synthesized and examined for its efficacy in delivering the raloxifene (RA) to mammary carcinoma. The synthesized CP-g-PA was confirmed by evaluating through various spectral and morphological attributes. Further, the central composite design-response surface methodology with two factors at three levels was utilized to obtain the optimized and stable polymeric micelles. The optimized formulation was subjected to in vitro and in vivo evaluation. RA loaded polymeric micelles (RA-PMs) were spherical in shape with particle size less than 100 nm and high entrapment efficiency (77.02%). The developed formulation exhibited pH-dependent release profile of RA when loaded in polymeric micelles and provides substantial compatibility to erythrocytes. In vivo pharmacokinetic study demonstrates that RA-PMs offers higher mean residence time and volume of distribution as compared to pure RA. Besides, the biodistribution study manifested enhanced drug concentration in tumor and decreased concentration in other tissue as compared to pure drug. The treatment with RA-PMs also increases the median survival time, tumor inhibition rate and % increase in life span of the tumor bearing rats. Overall, the results pointed towards the overwhelming response of RA when loaded into micelles made from CP-g-PA.
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Antineoplásicos , Micelas , Animales , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Portadores de Fármacos , Estudios de Factibilidad , Glucanos , Ácido Palmítico , Tamaño de la Partícula , Polímeros , Clorhidrato de Raloxifeno , Ratas , Distribución TisularRESUMEN
Paper industry uses cationic polymers for imparting strong bonds with pulp furnish to enhance strength properties. Due to environmental reasons, emphasis is on utilization of biobased polymers in place of synthetic. Sugarcane bagasse, an agro-industrial waste, was processed for extraction of alpha cellulose and preparation of cationic derivative. Reaction conditions were optimized to achieve highly substituted cationic derivative with insertion of 2-hydroxy-3-(trimethylammonium) propyl group. Artificial neural network (ANN) was applied to analyze the experimental data for cationization modeling. Maximum degree of substitution 0.66, was achieved at 5.0 M NaOH/anhydro glucose unit (AGU), 20 °C alkalization temperature, 8 min alkalization time, 3.5 M/AGU etherification agent concentration, 45 min time and 60 °C etherification reaction temperature. The experimental results showed that mean square error values for input parameters were significantly low. The ANN based regression values of the output, and computed values of target were close to unity. ANN based fitting indicates better performance level to predict the degree of substitution. The synthesized cationic cellulose was characterized through FTIR, XRD, NMR, FESEM and TGA. The activity of cationized cellulose as wet-end additive was tested for bagasse, wheat straw and recycled pulps due to their shorten fiber and feeble pulp characters than wood pulp.
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Celulosa/química , Saccharum/química , Cationes/química , Residuos Industriales , Polímeros/química , Reciclaje/métodos , TemperaturaRESUMEN
The present investigation entails the synthesis of smart pullulan polymeric micelles for evaluating its tumor targeting potential. For this purpose, two step polymerization synthesis reactions were conducted. In the first step, carbamoylethylation occurs by reaction of the free alcoholic moieties at 6th position of glucopyranose unit of pullulan with acrylamide in presence of alkali to obtain carbamoylethyl pullulan (CmP). In the second step, CmP undergoes graft polymerization with stearic acid (SA) to obtain CmP-g-stearic acid diblock co-polymer (CmP-g-SA) as evident from FTIR and NMR analysis. The XpRD spectra showed crystalline nature that was further confirmed by SEM indicating rough and poly-porous morphology. The QbD based optimized formulations of raloxifene HCl (RLX) loaded polymeric micelles (RLX PMs) exhibited pH-dependent release profile with added advantage of 1.2 times reduction in percentage hemolysis giving substantial compatibility with erythrocytes. In vivo pharmacokinetic performance of RLX PMs suggested enhanced mean residence time and volume of distribution. Besides, the biodistribution study of RLX PMs manifested enhanced entry of RLX in mammary carcinoma tissues as compared to normal tissues suggested that CmP-g-SA based micelles enhanced the anti-tumor activity of RLX. Overall, the findings pointed toward the biocompatibility of CmP-g-SA as a potential carrier system for the delivery of RLX.
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Micelas , Neoplasias , Humanos , Glucanos , Neoplasias/tratamiento farmacológico , Polímeros , Clorhidrato de Raloxifeno/química , Ácidos Esteáricos , Distribución TisularRESUMEN
Cleaner production of sugars and pulp from renewable feedstocks has captured significant scientific attention in the recent past because they can be used for various end applications. In the papermaking industry, a major fraction of hemicellulosic sugars is lost during the pulping. The present study aims at retrieving these hemicellulosic sugars through alkali-, hot-water-, and acid-mediated extraction prior to pulping, which otherwise would have been lost during pulping and washing of pulp. These retrieved sugars can be used as feedstocks for renewable energy and value-added products. Different pretreatments were applied, aided with varying temperature, chemical concentrations, and time. Substantial amounts of total reducing sugars (TRSs) up to 21.98, 13.2, and 15.01% were extracted prior to pulping by acid, alkali, and hot-water pretreatments. Compositions of mono sugars present in the treated liquor were also characterized and confirmed by high-performance liquid chromatography analysis. The morphological changes in the wheat straw after pre-extraction were studied using the field emission gun scanning electron microscopy technique. Pulping of untreated and pretreated wheat straw was carried out at different alkali charges (12, 14, and 16% NaOH). Among all, acid-pretreated straw showed an increase in pulp yield by 10.9% at a 16% alkali charge. Physical strength properties of different pulps were further examined. Alkali- and hot-water-pretreated straw pulp retained 94.26 and 83.16% tensile indices and 92.43 and 87.02% burst indices, respectively. An increase in tear index up to 4.32, 2.01, and 2.30% for alkali-, hot-water-, and acid-pretreated straw pulp was achieved, respectively. Hot-water- and alkali-pretreated wheat straw was observed to be conducive for paper production. The integrated use of wheat straw for extraction of underutilized sugars and pulp production in this way may serve as a key stepping stone for future biorefinery designs in pulp and paper mills.
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The increasing demand for high-density data storage leads to an increasing interest in novel memory concepts with high scalability and the opportunity of storing multiple bits in one cell. A promising candidate is the redox-based resistive switch repositing the information in form of different resistance states. For reliable programming, the underlying physical parameters need to be understood. We reveal that the programmable resistance states are linked to internal series resistances and the fundamental nonlinear switching kinetics. The switching kinetics of [Formula: see text]-based cells was investigated in a wide range over 15 orders of magnitude from 10[Formula: see text] s to 250 ps. The capacitive charging time of our device limits the direct observation of the set time below 770 ps, however, we found indication for an intrinsic switching speed of 10 ps at a stimulus of 3 V. On all time scales, multi-bit data storage capabilities were demonstrated. The elucidated link between fundamental material properties and multi-bit data storage paves the way for designing resistive switches for memory and neuromorphic applications.
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The synthesis of carbamoylethyl locust bean gum (CLBG) was optimized using Plackett-Burman design. The generated model showed high significance (p < 0.05) to all the response variables which justifies the authenticity of the designed model. The optimal conditions i.e. acrylamide (5.12 mM), sodium hydroxide (3.00 mM), reaction temperature (50.97 °C) and reaction time (2.00 h) supported maximum -CONH2 content (5.44%), -COOH content (3.04%), degree of substitution (0.85) and product yield (7.25%, w/w). Carbamoylethylation of locust bean gum (LBG) involved substitution of its hydroxyl (-OH) moieties with amide group (-CH2CH2CONH2). FTIR and NMR spectroscopy confirmed the addition of amide group to CLBG. Scanning electron microscopy assured the slight rough surface of CLBG particles. Differential scanning calorimetry showed that carbamoylethylation of LBG lowered its melting temperature range (205.60-272.45 °C). However, the amorphous nature, non-Newtonian flow and shear-thinning behaviour of pure LBG were retained in CLBG. Further, CLBG films prepared with glycerol (1%, w/w, plasticizer) showed partially smooth surface and have clear transversal cross-sections. CLBG-glycerol films were highly water resistant and almost transparent. Further, CLBG-glycerol films showed good tensile strength (18.55 ± 0.02 MPa) and higher percentage elongation (6.11 ± 0.01%). Water vapor transmission rate of CLBG-glycerol film was quite lower (0.211 ± 0.001 g.mm/h.m2.kPa) which verified its higher resistance towards water.
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Galactanos/química , Mananos/química , Gomas de Plantas/química , Reología , Agua/química , Acrilamida/química , Glicerol/química , Temperatura , Resistencia a la Tracción , ViscosidadRESUMEN
BACKGROUND: Excessive blue light light-emitting diode (LED) exposure and consequent oxidative stress causes corneal damage and corneal injuries are the major problem arising these days due to excessive use of mobile phone, TV, environment pollution, etc. Objective: In the present investigation, the protectiveness of carboxymethyl Terminalia catappa (CTC) from blue light LED-induced corneal damage was explored. METHODS: For this purpose, Terminalia catappa (TC) was functionalized by carboxymethylation and its structural modification was confirmed by spectral attributes. Further, the CTC protective eye drop formulations (0.025-1%, w/v) were prepared and evaluated for their capability of protection from blue light LEDinduced corneal damage as compared to CTC protective eye gel (1.25-7%, w/v). The findings pointed towards excellent protection of CTC gel formulations as compared to CTC eye drop formulations. In addition, the prepared optimized CTC gel had thixotropic behavior as evident from percentage structural recovery which was 1.75 fold higher than marketed formulation (I-Comfort, HPMC 2%, w/v). The safety and non-toxicity of CTC protective eye drop and gel were confirmed by HET-CAM test. Further, a rat eye model was implemented that mimic blue light light-emitting diode induced corneal damage in day to day life to assess the protective effect of CTC protective eye drop and gel. RESULTS: The order of protectiveness of CTC formulations was found to be CTC protective eye gel (4%, w/v) (no corneal damage)>marketed eye gel (12.34% corneal damage)=CTC protective eye drop (0.75%, w/v) (17.48% corneal damage)> marketed eye drop (51% corneal damage). The mechanism behind the protective effect of CTC eye drop and gel was associated with good free radical scavenging activity and corneal adhesive property of CTC. It is established from the present work that, carboxymethyl Terminalia catappa has protective action against blue light light-emitting diode induced corneal damage.
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Lesiones de la Cornea/prevención & control , Polisacáridos/aislamiento & purificación , Polisacáridos/farmacología , Terminalia/química , Administración Oftálmica , Animales , Lesiones de la Cornea/etiología , Relación Dosis-Respuesta a Droga , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/aislamiento & purificación , Depuradores de Radicales Libres/farmacología , Luz/efectos adversos , Soluciones Oftálmicas , Estrés Oxidativo/efectos de los fármacos , Polisacáridos/química , Sustancias Protectoras/química , Sustancias Protectoras/aislamiento & purificación , Sustancias Protectoras/farmacología , RatasRESUMEN
Chemical modification of waste paper offers a good prospective for environment protection through minimizing the waste density. The study develops a new opportunity for recycling of waste paper through hydroxypropyl cellulose (HPC) synthesis. Waste paper cellulose was hydroxypropylated by alkalization and etherification process. The hydroxypropylation reaction conditions were optimized for reactant concentrations, reaction time and temperature. Maximum DS (1.15) was achieved at 1.5â¯M/anhydro glucose unit (AGU) NaOH concentration, 40⯰C alkalization temperature, 2.5â¯h alkalization time, 27.82â¯M/AGU propylene oxide concentration, 3.5â¯h reaction time for hydroxypropylation and 55⯰C hydroxypropylation reaction temperature. HPC sample (DSmax.â¯=â¯1.15) was examined for rheological behaviour and characterized by using FTIR spectroscopy, 1H NMR spectroscopy, XRD, HPLC and SEM techniques. This environment friendly approach explored an alternative new route for waste paper recycling and substantiated waste paper as a promising feedstock for HPC synthesis. The study further forms a real stepping stone towards resource conservation and recycling.
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The present investigation was aimed to develop a rabbit model for protecting the rabbit eye from systematically induced precorneal tear film (PTF) damage, evaluation of carboxymethyl pullulan for its protective action against PTF damage and its curative potential. For the same, pullulan was modified by carboxymethylation and structural modification was confirmed by spectral attributes. Further, the carboxymethyl pullulan (CMP) solutions (0.1-2.0%, w/v) were evaluated for their physical properties and its concentration 1.5% (w/v) was found to fit the criterion to prepare an eye solution. The safety and non-toxicity of CMP (1.5%, w/v) eye solution was confirmed by HET-CAM method and rabbit eye irritation test. Further, a systematic rabbit eye model was developed that mimic PTF damage in day to day life. Therefore, three levels of PTF damage were developed equating symptoms of damage due to high temperature (level I) or long term mobile use (level II) or heavy air pollution (level III). Thus, a representative model with benzalkonium chloride (BAC, 0.1% v/v, 0.2% v/v and 0.3% v/v), administered two drops twice a day for two days to develop level I, level II and level III eye damage. The CMP (1.5%, w/v) eye solution possessed a protective potential against level I and II PTF damage. The rabbit eyes remained unharmed and comparable with the normal control during the complete experimental period. Additionally, CMP (1.5%, w/v) eye solution has shown early fast recovery (8 days) from PTF damage induced by instillation of PTF damage agent (BAC). Carboxymethyl pullulan eye protective solution has normalized the tear film stability in rabbit eye model. It is established from the present work that, carboxymethyl pullulan has protective action against precorneal tear film damage and it potentiates the early recovery too.