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1.
Plant Physiol ; 191(2): 1305-1323, 2023 02 12.
Artículo en Inglés | MEDLINE | ID: mdl-36417197

RESUMEN

Nitrogen is critical for plant growth and development. With the increase of nitrogen fertilizer application, nitrogen use efficiency decreases, resulting in wasted resources. In apple (Malus domestica) rootstocks, the potential molecular mechanism for improving nitrogen uptake efficiency to alleviate low-nitrogen stress remains unclear. We utilized multi-omics approaches to investigate the mechanism of nitrogen uptake in two apple rootstocks with different responses to nitrogen stress, Malus hupehensis and Malus sieversii. Under low-nitrogen stress, Malus sieversii showed higher efficiency in nitrogen uptake. Multi-omics analysis revealed substantial differences in the expression of genes involved in flavonoid and lignin synthesis pathways between the two materials, which were related to the corresponding metabolites. We discovered that basic helix-loop-helix 130 (bHLH130) transcription factor was highly negatively associated with the flavonoid biosynthetic pathway. bHLH130 may directly bind to the chalcone synthase gene (CHS) promoter and inhibit its expression. Overexpressing CHS increased flavonoid accumulation and nitrogen uptake. Inhibiting bHLH130 increased flavonoid biosynthesis while decreasing lignin accumulation, thus improving nitrogen uptake efficiency. These findings revealed the molecular mechanism by which bHLH130 regulates flavonoid and lignin biosyntheses in apple rootstocks under low-nitrogen stress.


Asunto(s)
Malus , Malus/metabolismo , Nitrógeno/metabolismo , Lignina/metabolismo , Multiómica , Flavonoides/metabolismo , Regulación de la Expresión Génica de las Plantas
2.
Molecules ; 28(18)2023 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-37764467

RESUMEN

To enhance the mechanical strength and cell adhesion of alginate hydrogel, making it satisfy the requirements of an ideal tissue engineering scaffold, the grafting of Arg-Gly-Asp (RGD) polypeptide sequence onto the alginate molecular chain was conducted by oxidation of sodium periodate and subsequent reduction amination of 2-methylpyridine borane complex (2-PBC) to synthesize alginate dialdehyde grafted RGD derivatives (ADA-RGD) with good cellular affinity. The interpenetrating network (IPN) composite hydrogels of alginate/polyvinyl alcohol/cellulose nanocrystals (ALG/PVA/CNCs) were fabricated through a physical mixture of ion cross-linking of sodium alginate (SA) with hydroxyapatite/D-glucono-δ-lactone (HAP/GDL), and physical cross-linking of polyvinyl alcohol (PVA) by a freezing/thawing method, using cellulose nanocrystals (CNCs) as the reinforcement agent. The effects of the addition of CNCs and different contents of PVA on the morphology, thermal stability, mechanical properties, swelling, biodegradability, and cell compatibility of the IPN composite hydrogels were investigated, and the effect of RGD grafting on the biological properties of the IPN composite hydrogels was also studied. The resultant IPN ALG/PVA/CNCs composite hydrogels exhibited good pore structure and regular 3D morphology, whose pore size and porosity could be regulated by adjusting PVA content and the addition of CNCs. By increasing the PVA content, the number of physical cross-linking points in PVA increased, resulting in greater stress support for the IPN composite hydrogels of ALG/PVA/CNCs and consequently improving their mechanical characteristics. The creation of the IPN ALG/PVA/CNCs composite hydrogels' physical cross-linking network through intramolecular or intermolecular hydrogen bonding led to improved thermal resistance and reduced swelling and biodegradation rate. Conversely, the ADA-RGD/PVA/CNCs IPN composite hydrogels exhibited a quicker degradation rate, attributed to the elimination of ADA-RGD by alkali. The results of the in vitro cytocompatibility showed that ALG/0.5PVA/0.3%CNCs and ADA-RGD/PVA/0.3%CNCs composite hydrogels showed better proliferative activity in comparison with other composite hydrogels, while ALG/PVA/0.3%CNCs and ADA-RGD/PVA/0.3%CNCs composite hydrogels displayed obvious proliferation effects, indicating that PVA, CNCs, and ADA-RGD with good biocompatibility were conducive to cell proliferation and differentiation for the IPN composite hydrogels.


Asunto(s)
Nanopartículas , Alcohol Polivinílico , Alcohol Polivinílico/química , Hidrogeles/química , Alginatos/química , Oligopéptidos , Celulosa/química
3.
Small ; 18(17): e2200175, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35307967

RESUMEN

Solar evaporation is one of the most attractive and sustainable approaches to address worldwide freshwater scarcity. Unfortunately, it is still a crucial challenge that needs to be confronted when the solar evaporator faces harsh application environments. Herein, a promising polymer molding method that combines melt blending and compression molding, namely micro extrusion compression molding, is proposed for the cost-effective fabrication of lightweight polyethylene/graphene nanosheets (PE/GNs) foam with interconnected vapor escape channels and surface micro-nanostructures. A contact angle of 155 ± 2°, a rolling angle of 5 ± 1° and reflectance of ≈1.6% in the wavelength range of 300-2500 nm appears on the micro-nanostructured PE/GNs foam surface. More interestingly, the micro-nanostructured PE/GNs foam surface can maintain a robust superhydrophobic state under dynamic impacting, high temperature and acid-/alkali solutions. These results mean that the micro-nanostructured PE/GNs foam surface possesses self-cleaning, anti-icing and photothermal deicing properties at the same time. Importantly, the foam exhibits an evaporation rate of 1.83 kg m-2 h-1 under 1 Sun illumination and excellent salt rejecting performance when it is used as a self-floating solar evaporator. The proposed method provides an ideal and industrialized approach for the mass production of solar evaporators suitable for practical application environments.


Asunto(s)
Grafito , Nanoestructuras , Purificación del Agua , Álcalis , Análisis Costo-Beneficio , Interacciones Hidrofóbicas e Hidrofílicas , Pinzas Ópticas , Polietileno
4.
Protein Expr Purif ; 200: 106171, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36103937

RESUMEN

The diverse biological activities of alginate oligosaccharides attracted extensive exploration of alginate lyases with various substrate specificity and enzymatic properties. In this study, an alginate lyase from Microbulbifer sp. ALW1, namely AlgL7, was phylogenetically classified into the polysaccharide lyase family 7 (PL7). The conserved amino acid residues Tyr606 and His499 in AlgL7 were predicted to act as the general acid/base catalysts. The enzyme was enzymatically characterized after heterologous expression and purification in E. coli. AlgL7 displayed optimal activity at 40 °C and pH 7.0. It had good stability at temperature below 35 °C and within a pH range of 5.0-10.0. AlgL7 exhibited good stability against the reducing reagent ß-ME and the surfactants of Tween-20 and Triton X-100. The degradation profiles of alginate indicated AlgL7 was a bifunctional endolytic alginate lyase generating alginate oligosaccharides with the degrees of polymerization 2-4. The degradation products of sodium alginate exhibited stronger antioxidant activities than the untreated polysaccharide. In addition, AlgL7 could directly digest Laminaria japonica to produce alginate oligosaccharides. These characteristics of AlgL7 offer a great potential of its application in high-value utilization of brown algae resources.


Asunto(s)
Alteromonadaceae , Laminaria , Alginatos/metabolismo , Aminoácidos , Antioxidantes , Proteínas Bacterianas/química , Escherichia coli/genética , Escherichia coli/metabolismo , Concentración de Iones de Hidrógeno , Laminaria/metabolismo , Octoxinol , Oligosacáridos/metabolismo , Polisacárido Liasas/química , Polisorbatos , Especificidad por Sustrato , Tensoactivos , Temperatura
5.
Inflammopharmacology ; 30(3): 695-704, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35290552

RESUMEN

OBJECTIVE: This study aimed to evaluate the effect of adjunctive melatonin supplementation on clinical outcomes after non-surgical periodontal treatment. METHODS: PubMed, Embase, and Web of Science databases were systematically searched for randomised controlled trials (RCTs) of melatonin adjuvant therapy for periodontitis from inception until May 2021. The systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and registered on The International Prospective Register of Systematic Reviews (PROSPERO) (CRD42021250630). The risk of bias of included studies was assessed according to the Cochrane Handbook for Systematic Reviews of Interventions. The pooled effect estimates were calculated by a random-effects model, and results were expressed as weighted mean differences (WMD). RESULTS: Seven RCTs comprising 412 participants were included in the meta-analysis. The pooled results showed that adjuvant use of melatonin for non-surgical periodontal treatment significantly improved the probing depth (PD) [WMD = - 1.18, 95% CI (- 1.75, - 0.62) I2 = 85.7%], clinical attachment loss (CAL) [WMD = - 1.16, 95% CI (- 1.60, - 0.72) I2 = 76.7%] and gingival index (WMD = - 0.29, 95%CI [- 0.48, - 0.11], I2 = 63.6%) compared with non-surgical treatment alone. In addition, subgroup analysis showed that higher doses of melatonin (3-10 mg) significantly improved PD [WMD = - 1.32, 95%CI (- 2.31, - 0.15) I2 = 93%] and CAL [WMD = - 1.30, 95%CI (- 1.80, - 0.81) I2 = 73.7%] compared with lower doses of melatonin (< 3 mg). CONCLUSIONS: We found that adjunctive melatonin supplementation can significantly improve the periodontal status after non-surgical treatment, suggesting that melatonin may be a new adjuvant therapy for periodontitis when non-surgical periodontal treatment alone cannot achieve the desired improvement.


Asunto(s)
Melatonina , Periodontitis , Humanos , Melatonina/uso terapéutico , Periodontitis/tratamiento farmacológico , Resultado del Tratamiento
6.
BMC Palliat Care ; 19(1): 181, 2020 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-33246449

RESUMEN

BACKGROUND: In end-of-life patients with advanced cancers, oral examination, oral care, and oral re-examination are crucial. Although oral symptoms are among the major complaints of end-of-life patients, few studies have focused on oral care in these patients. In this study, the association between oral symptoms and oral dryness among end-of-life patients was examined, and improvement of oral conditions after oral care interventions by a professional dentist was quantified. METHODS: This prospective intervention study included 27 terminally ill patients with advanced cancers in a hospice ward. Professional oral care was administered every morning, and the improvement of oral conditions was assessed by comparing oral conditions before and after the intervention. Oral assessment was performed using the Oral Health Assessment Tool (OHAT) and Oral Assessment Guide. Oral dryness was evaluated through Clinical Diagnosis Classification of oral dryness and an oral moisture device. Oral cleanliness was evaluated using a bacterial counter, and tongue smears were collected for Candida examination; furthermore, oral function was recorded. RESULTS: The presence of oral mucositis was closely associated with severe oral dryness (odds ratio [OR] = 14.93; 95% confidence interval [CI]: 1.95-114.38). The level of oral debris retention was significantly related to the degree of oral dryness (OR = 15.97; 95% CI: 2.06-123.72). The group with higher scores (OHAT > 8), which represent poor oral conditions, showed severe oral dryness (OR = 17.97; 95% CI: 1.45-223.46). Total OHAT scores (median: 7 vs 2) and those of other subgroups (lip, tongue, gums and tissues, saliva, and oral cleanliness showed a significant decrease after the intervention. Furthermore, the occurrence of mucositis (47.1% vs 0%), candidiasis rate (68.8% vs 43.8%), oral dryness self-sensation (63.6% vs 9.1%), and severe oral debris (52.9% vs 11.8%) decreased significantly. CONCLUSIONS: Proper oral care can improve oral health and hygiene, reduce the rate of mucositis, reduce the sensation of oral dryness, increase oral moisture, and reduce the chances of oral infections among end-of-life patients. Daily oral care is necessary and can alleviate oral discomfort, increase food intake, and increase the chances of communication between end-of-life patients and their families.


Asunto(s)
Atención Odontológica/métodos , Neoplasias/complicaciones , Cuidado Terminal/métodos , Adulto , Atención Odontológica/normas , Atención Odontológica/estadística & datos numéricos , Femenino , Hospitales para Enfermos Terminales/organización & administración , Hospitales para Enfermos Terminales/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/terapia , Estudios Prospectivos , Investigación Cualitativa , Estadísticas no Paramétricas , Encuestas y Cuestionarios , Taiwán , Cuidado Terminal/estadística & datos numéricos
7.
J Infect Dis ; 217(7): 1069-1073, 2018 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-29294037

RESUMEN

Background: Cytomegalovirus (CMV) establishes a lifelong latent infection after primary infection and may reactivate periodically, with the shedding of infectious virus in body fluids. To better understand the prevalence and shedding model of CMV in immunocompetent seropositive women of childbearing age, a 6-month longitudinal study was conducted in healthy female college students. Methods: A total of 102 nonpregnant female college students aged 18-30 years were enrolled and followed up every 2 weeks for 6 months. Saliva and urine samples were collected at each visit. Serum samples were collected at the first and last visits. Results: All participants were positive for anti-CMV immunoglobulin G (IgG) at entry. During the 6-month period, 29.4% of participants (30 of 102) shed CMV intermittently in saliva or urine. At each visit, the CMV shedding prevalence varied from 2.0% to 10.4% and presented only in 1 bodily fluid. The viral load was low and did not induce marked antibody increases. The baseline anti-CMV IgG level was not found to be associated with viral shedding. Conclusions: CMV shedding in saliva and urine is common and intermittent and does not stimulate an anamnestic antibody response in seropositive immunocompetent women of childbearing age with a low risk of exposure to exogenous infectious sources.


Asunto(s)
Anticuerpos Antivirales/sangre , Citomegalovirus/fisiología , Inmunoglobulina G/sangre , Esparcimiento de Virus/fisiología , Adolescente , Adulto , Femenino , Humanos , Inmunocompetencia , Estudios Longitudinales , Saliva/virología , Estudios Seroepidemiológicos , Estudiantes , Universidades , Orina/virología , Adulto Joven
8.
J Virol ; 91(15)2017 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-28515293

RESUMEN

Virus-like vesicles (VLVs) are membrane-enclosed vesicles that resemble native enveloped viruses in organization but lack the viral capsid and genome. During the productive infection of tumor-associated gammaherpesviruses, both virions and VLVs are produced and are released into the extracellular space. However, studies of gammaherpesvirus-associated VLVs have been largely restricted by the technical difficulty of separating VLVs from mature virions. Here we report a strategy of selectively isolating VLVs by using a Kaposi's sarcoma-associated herpesvirus (KSHV) mutant that is defective in small capsid protein and is unable to produce mature virions. Using mass spectrometry analysis, we found that VLVs contained viral glycoproteins required for cellular entry, as well as tegument proteins involved in regulating lytic replication, but lacked capsid proteins. Functional analysis showed that VLVs induced the expression of the viral lytic activator RTA, initiating KSHV lytic gene expression. Furthermore, employing RNA sequencing, we performed a genomewide analysis of cellular responses triggered by VLVs and found that PRDM1, a master regulator in cell differentiation, was significantly upregulated. In the context of KSHV replication, we demonstrated that VLV-induced upregulation of PRDM1 was necessary and sufficient to reactivate KSHV by activating its RTA promoter. In sum, our study systematically examined the composition of VLVs and demonstrated their biological roles in manipulating host cell responses and facilitating KSHV lytic replication.IMPORTANCE Cells lytically infected with tumor-associated herpesviruses produce a high proportion of virus-like vesicles (VLVs). The composition and function of VLVs have not been well defined, largely due to the inability to efficiently isolate VLVs that are free of virions. Using a cell system capable of establishing latent KSHV infection and robust reactivation, we successfully isolated VLVs from a KSHV mutant defective in the small capsid protein. We quantitatively analyzed proteins and microRNAs in VLVs and characterized the roles of VLVs in manipulating host cells and facilitating viral infection. More importantly, we demonstrated that by upregulating PRDM1 expression, VLVs triggered differentiation signaling in targeted cells and facilitated viral lytic infection via activation of the RTA promoter. Our study not only demonstrates a new strategy for isolating VLVs but also shows the important roles of KSHV-associated VLVs in intercellular communication and the viral life cycle.


Asunto(s)
Regulación Viral de la Expresión Génica , Herpesvirus Humano 8/fisiología , Interacciones Huésped-Patógeno , Proteínas Represoras/biosíntesis , Transducción de Señal , Virosomas/química , Replicación Viral , Diferenciación Celular , Línea Celular , Herpesvirus Humano 8/química , Humanos , Proteínas Inmediatas-Precoces/metabolismo , Factor 1 de Unión al Dominio 1 de Regulación Positiva , Transactivadores/metabolismo , Regulación hacia Arriba
9.
Eur J Nutr ; 55(4): 1573-81, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26160548

RESUMEN

PURPOSE: There are wide inter-individual differences in glycemic response (GR). We aimed to examine key digestive parameters that influence inter-individual and ethnic differences in GR in healthy Asian individuals. METHODS: Seventy-five healthy male subjects (25 Chinese, 25 Malays, and 25 Asian-Indians) were served equivalent available carbohydrate amounts (50 g) of jasmine rice (JR) and basmati rice (BR) on separate occasions. Postprandial blood glucose concentrations were measured at fasting (-5 and 0 min) and at 15- to 30-min interval over 180 min. Mastication parameters (number of chews per mouth and chewing time per mouthful), saliva α-amylase activity, AMY1 gene copy numbers and gastric emptying rate were measured to investigate their relationships with GR. RESULTS: The GR for jasmine rice was significantly higher than for basmati rice (P < 0.001). The median number of AMY1 gene copies was 6, with a range of 2-15. There was a significant positive relationship between AMY1 copy number and α-amylase activity (P = 0.002). There were no significant ethnic differences in GR. For both rice varieties, the number of chews per mouthful was positively associated with the GR (JR, P = 0.011; BR, P = 0.005), while chewing time per mouthful showed a negative association (JR, P = 0.039; BR, P = 0.016). Ethnicity, salivary α-amylase activity, particle size distribution, gastric emptying rate and AMY1 gene copy numbers were not significant contributors to GR (P > 0.05). CONCLUSION: Mastication parameters contribute significantly to GR. Eating slowly and having larger food boluses before swallowing (less chewing), both potentially modifiable, may be beneficial in glycemic control.


Asunto(s)
Pueblo Asiatico , Glucemia/metabolismo , Digestión/etnología , Índice Glucémico , Masticación , Adiposidad , Adulto , Presión Sanguínea , Índice de Masa Corporal , China , Estudios Cruzados , Carbohidratos de la Dieta/administración & dosificación , Carbohidratos de la Dieta/análisis , Vaciamiento Gástrico/genética , Vaciamiento Gástrico/fisiología , Dosificación de Gen , Humanos , India , Modelos Lineales , Malasia , Masculino , Oryza/química , Oryza/clasificación , Tamaño de la Partícula , Periodo Posprandial , alfa-Amilasas Salivales/genética , Circunferencia de la Cintura , Adulto Joven
10.
Water Sci Technol ; 70(5): 851-7, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25225932

RESUMEN

Graphene oxide (GO) was chemically modified with poly(ethylene imine) (PEI) to improve its colloidal stability and was investigated as a potential adsorbent for the removal of methyl orange (MO). The synthesis of PEI-GO was verified with a Fourier transform infrared spectrometer and thermogravimetric analysis. A series of adsorption experiments were carried out to investigate the adsorption capacity of PEI-GO. Adsorption kinetics and thermodynamics studies were performed, and the thermodynamic parameters were calculated. The results showed that PEI could improve the colloidal stability of GO in aqueous solution, and the obtained PEI-GO showed a macroscopically homogeneous dispersion after more than three months. After standing for 90 days, the Brunauer-Emmett-Teller specific surface area of GO decreased from 353 to 214 m2·g(-1), while that of PEI-GO remained almost unchanged (from 432 to 413 m2·g(-1)). The PEI-GO exhibited significantly faster kinetic and higher adsorption capacity for MO than GO. Moreover, PEI-GO had a good adsorption capacity in the acidic range, and the highest adsorption of MO occurred at pH=6.0. The adsorption of MO on PEI-GO was an endothermic, spontaneous and physisorption process.


Asunto(s)
Compuestos Azo/aislamiento & purificación , Grafito/química , Iminas/química , Óxidos/química , Polietilenos/química , Contaminantes Químicos del Agua/aislamiento & purificación , Adsorción , Coloides , Cinética , Espectroscopía Infrarroja por Transformada de Fourier , Termodinámica
11.
Artículo en Inglés | MEDLINE | ID: mdl-25072768

RESUMEN

This investigation examines how extracellular polymeric substances (EPSs) and environmental factors affect the bioaccumulation and toxicity of inorganic mercury (+2 oxidation state, Hg(II)) using a culture of Microcystis aeruginosa, which dominates eutrophic reservoir populations. The identified EPSs were classified as carbohydrates and proteins. Evaluation of the bioaccumulation of Hg(II) in cells by multiple regression analysis reveals that the concentration of EPSs in filtrate, the initial concentration of Hg(II) in medium, and the culture age significantly affected the amount of Hg(II) accumulated. Composition profiles revealed that the concentrations of soluble carbohydrates were significantly higher in Hg(II)-accumulated cells than in the control ones. Preliminary results based on scanning electron microscopic (SEM) map investigations suggest that most of the Hg(II) was accumulated in the cytoplasm (intracellular). Additionally, the effective concentrations (EC50) of Hg(II) that inhibit the growth of M. aeruginosa were 38.6 µg L(-1) in the logarithmic phase and 17.5 µg L(-1) in the stationary phase. As expected, the production of more EPSs in the logarithmic phase typically implies higher EC50 values because EPSs may be regarded as a protective barrier of cells against an external Hg(II) load, enabling them to be less influenced by Hg(II).


Asunto(s)
Mercurio/metabolismo , Microcystis/metabolismo , Biodegradación Ambiental , Matriz Extracelular/metabolismo , Mercurio/toxicidad , Microcystis/efectos de los fármacos , Polímeros/metabolismo
12.
Int J Biol Macromol ; 273(Pt 2): 133003, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38851607

RESUMEN

Enzymatic hydrolysis is important for lignocellulosic biomass conversion into fermentable sugars. However, the nonproductive adsorption of enzyme on lignin was major hinderance for the enzymatic hydrolysis efficiency. In this study, non-productive adsorption mechanism of cellulase component cellobiohydrolase (CBH) onto lignin was specific investigated. Research revealed that the adsorption behavior of CBH on eucalyptus alkali lignin (EuA) was affected by reaction conditions. As study on the adsorption kinetic, it was indicated that the adsorption cellulose binding domain (CBD) of CBH onto EuA well fitted with Langmuir adsorption model and pseudo second-order adsorption kinetics model. And the tyrosine site related to the adsorption of CBD onto lignin was proved by the fluorescence and UV spectra analysis. The results of this work provide a theoretical guidance to understanding the nonproductive adsorption mechanism and building method to reduce the adsorption of cellulase on the lignin.


Asunto(s)
Celulosa 1,4-beta-Celobiosidasa , Eucalyptus , Lignina , Lignina/química , Celulosa 1,4-beta-Celobiosidasa/química , Celulosa 1,4-beta-Celobiosidasa/metabolismo , Adsorción , Cinética , Eucalyptus/química , Hidrólisis
13.
Int J Biol Macromol ; 259(Pt 1): 128891, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38143065

RESUMEN

The toxic volatile organic compounds (VOCs), especially formaldehyde (FA), released from decoration materials pose a great threat to human health. In this study, formaldehyde adsorption performance of the specially formulated nanocellulose/chitosan aerogel (CNFCA) was investigated in simulated atmosphere. The physicochemical property of the composite aerogel was characterized, which had a large specific surface area (153.67 m2/g), a rough surface and an ultra-thin and porous structure. The composite aerogel showed excellent adsorption capacity for the formaldehyde, its theoretical maximum adsorption capacity was as high as 83.89 mg/g, and the adsorption process was more in accordance with the pseudo-second-order kinetics. The chromogenic reaction between the 4-amino-3-benzo-5-mercapto-1,2,4-triazolium (AHMT) and CNFCA was found that the color of the composite aerogel was depended on the free formaldehyde concentration. Based on this phenomenon, a colorimetric card was proposed and built to detection the formaldehyde in the atmosphere. Moreover, the adsorption mechanism research was found that the CNFCA with a multilayer structure belonged to physicochemical complex adsorption.


Asunto(s)
Quitosano , Humanos , Adsorción , Atmósfera , Celulosa , Formaldehído
14.
Bioresour Technol ; 395: 130400, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38286169

RESUMEN

The rational use of bamboo to make dissolving pulp can offer up new opportunities for cellulose production, alleviating wood scarcity. Bamboo contains a high content of non-fiber cells, which presents technical challenges in dissolving pulp production by the conventional process. In this study, a process concept of separating hemicelluloses is presented by fiber fractionation and purification for cleaner production of bamboo dissolving pulp: bamboo kraft pulp was fractionated into long-fiber and short-fiber fractions. The cellulose-rich long-fiber fraction was converted to dissolving pulp by further purification treatment with acid hydrolysis and cold caustic extraction. The hemicellulose-rich short-fiber fraction was used for papermaking. The laboratory results were confirmed by those from mill trials. The combined pulp yield (dissolving pulp + paper-grade pulp) reached 49 %, which was significantly higher than that of the conventional pre-hydrolysis kraft pulping process. Furthermore, the quality of dissolving pulp was higher due to inherently higher cellulose content of long-fiber fraction.


Asunto(s)
Celulosa , Fraccionamiento Químico , Madera , Hidrólisis
15.
Am J Orthod Dentofacial Orthop ; 144(3): 381-90, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23992810

RESUMEN

INTRODUCTION: Congenitally missing permanent teeth are common in patients with clefts. This retrospective study was conducted to evaluate the craniofacial characteristics in patients with unilateral complete cleft lip and palate with congenitally missing permanent teeth. METHODS: A series of 73 consecutive patients with nonsyndromic unilateral complete cleft lip and palate were enrolled. Evaluation of congenitally missing permanent teeth was based on the panoramic films taken from 7 to 11 years of age. The cephalometric films taken around 9 years of age were used to compare the craniofacial morphology in patients with no congenitally missing permanent teeth (n = 20) and 1 (n = 25), 2 (n = 18), and 3 (n = 10) congenitally missing permanent teeth. The Spearman correlation coefficient was used to assess the association of increased numbers of congenitally missing permanent teeth with each cephalometric parameter. RESULTS: Anterior facial height, distance from the maxillary incisor and first molar to the palatal plane, and overjet decreased as the number of congenitally missing permanent teeth increased in patients with unilateral cleft lip and palate. CONCLUSIONS: Unilateral cleft lip and palate patients with congenitally missing permanent teeth have a unique craniofacial morphology with a reduced vertical dimension.


Asunto(s)
Anodoncia/complicaciones , Fisura del Paladar/complicaciones , Fisura del Paladar/patología , Desarrollo Maxilofacial , Cefalometría , Niño , Fisura del Paladar/fisiopatología , Femenino , Humanos , Modelos Lineales , Masculino , Maxilar/crecimiento & desarrollo , Sobremordida/etiología , Estudios Retrospectivos , Cráneo/crecimiento & desarrollo , Estadísticas no Paramétricas , Dimensión Vertical
16.
Sci Total Environ ; 858(Pt 2): 159934, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36343821

RESUMEN

Microplastics are ubiquitous in the natural environment and have the potential to endanger the natural environment, ecology and even human health. A series of microfluidic experiments by using soft lithography technology were carried out to investigate the effect of flow rate, particle volume fraction, particle size and pore/throat ratio on microplastics migration and deposition at the pore scale. We discovered a range of deposition patterns of the spherical microplastics from no particle deposition, to discontinuous particle layer, and to continuous particle layers in the retained liquid in the pores, depending on the particle size and volume fraction. Several metrics, including air saturation, probability of particle detainment, expansion ratio and thickness of residual liquid, were quantified to examine the role of various parameters on particle migration and retention of microplastics. At low flow rate (Q = 0.05 µL/min), microplastics migration and deposition were sensitive to changes in particle volume fraction, particle size and pore/throat ratio. In contrast, at high flow rates (Q > 5 µL/min), the migration and retention of particles were mainly controlled by strongly channelized air invasion pattern, while the particle volume fraction, particle size and pore/throat size ratio have only secondary influence. At intermediate range of flow rates, microplastics migration and deposition were dramatically impacted by flow rate, particle volume fraction, particle size and pore/throat ratio. This work improves the understanding of the mechanisms of particle migration and retention in porous media and can provide a reference for more accurate assessment of the exposure levels and times of microplastics in soil and groundwater systems.


Asunto(s)
Microplásticos , Plásticos , Humanos , Porosidad , Suelo , Tamaño de la Partícula
17.
ACS Appl Mater Interfaces ; 15(39): 46538-46549, 2023 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-37729522

RESUMEN

A transparent film integrating antifouling, antifogging, and antibacterial properties is crucial for its application as a protective mask, goggles, or lens. Herein, applying dynamic injection molding coupled with a bionic gradient template, a fast and efficient method is proposed for the preparation of the bionic polystyrene surface (BNPPS) with a cicada wing-inspired nanopillar structure. The contact angle of the BNPPS film increases continuously along the wing vein, while the sliding angle decreases continuously, mimicking the gradient wetting state of a cicada wing and providing excellent self-propelled removal properties for tiny water droplets. Notably, the BNPPS film has a transmittance higher than 90% and a reflectivity lower than 5% in the visible light range. Dyeing water, milk, juice, cola, and ink can slide smoothly from the BNPPS film surface without leaving any residue. Importantly, the nanopillars on the BNPPS film surface can penetrate and kill most of the Escherichia coli within 20 min. Therefore, the prepared BNPPS film with sufficient mechanical strength gathers the unique properties of the cicada wing together. The proposed research is expected to offer valuable guidance for fabricating self-cleaning, antifogging, and antibacterial optical devices that could be utilized in medical and vision systems operating in harsh environments.


Asunto(s)
Hemípteros , Poliestirenos , Animales , Humectabilidad , Antibacterianos/farmacología , Antibacterianos/química , Agua , Escherichia coli
18.
Ear Nose Throat J ; : 1455613231185020, 2023 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-37491883

RESUMEN

The clinical diagnosis and treatment, including information such as age, history, clinical symptoms, signs, audiology, imaging examination, mode of operation, and postoperative follow-up, of a patient with suppurative temporomandibular arthritis caused by chronic suppurative otitis media were analyzed. As conservative drug treatment and drainage surgery were ineffective, the patient was treated with microscopic open radical mastoidectomy, tympanoplasty, the plasty of the cavity of auricular concha, facial nerve decompression, coarctation of the mastoid cavity combined with otoendoscpic resection of the lower temporomandibular lesions, and standard anti-inflammatory treatment after surgery. The patient appeared to be cured at the 3-month follow-up. The ear canal was dry, without any preauricular swelling, purulent ear discharge, otalgia, limitation of mouth opening, or other symptoms. A clear diagnosis by defining the scope of the lesions, analysis of the transmission route of the lesions, and standard conservative treatment, local drainage, and surgical resection, if necessary, are recommended for patients with suppurative temporomandibular arthritis.

19.
Int J Biol Macromol ; 227: 749-761, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36563816

RESUMEN

A highly oriented poly(l-lactic acid) (PLLA), with a blood vessel-like biomimetic structure, was fabricated using solid-phase hot drawing technology and homo-epitaxial crystallization to improve the mechanical properties and biocompatibility of PLLA. Long chain branched PLLA (LCB-PLLA) was prepared through a two-step ring-opening reaction, and a consequent draw as high as 1000 % was achieved during the hot drawing. The modulus and tensile strength were found to have increased through the formation of oriented shish-kebab like crystals along the drawing direction during processing. Furthermore, PLLA nano-lamellae were formed on the surface of the oriented plates via the introduction of homo-epitaxial crystallization. The high degree of orientation and epitaxial crystallization substantially enhanced the biocompatibility of the PLLA by prolonging clotting time, decreasing the rate of hemolysis, and increasing the cell growth and reproduction of the osteoblasts.


Asunto(s)
Materiales Biocompatibles , Biónica , Materiales Biocompatibles/química , Poliésteres/química , Resistencia a la Tracción
20.
Atten Percept Psychophys ; 85(7): 2296-2306, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37794299

RESUMEN

People recognize familiar faces better than unfamiliar faces. However, it remains unknown whether familiarity affects part-based and/or holistic processing. Wang et al., Frontiers in Psychology, 6, 559 (2015), Vision Research, 157, 89-96 (2019) found both enhanced part-based and holistic processing in eye relative to mouth regions (i.e., in a region-selective manner) for own-race and own-species faces, i.e., faces with more experience. Here, we examined the role of face familiarity in eyes (part-based, region-selective) and holistic processing. Face familiarity was tested at three levels: high-familiar (faces of students from the same department and the same class who attended almost all courses together), low-familiar (faces of students from the same department but different classes who attended some courses together), and unfamiliar (faces of schoolmates from different departments who seldom attended the same courses). Using the old/new task in Experiment 1, we found that participants recognized eyes of high-familiar faces better than low-familiar and unfamiliar ones, while similar performance was observed for mouths, indicating a region-selective, eyes familiarity effect. Using the "Perceptual field" paradigm in Experiment 2, we observed a stronger inversion effect for high-familiar faces, a weaker inversion effect for low-familiar faces, but a non-significant inversion effect for unfamiliar faces, indicating that face familiarity plays a role in holistic processing. Taken together, our results suggest that familiarity, like other experience-based variables (e.g., race and species), can improve both eye processing and holistic processing.


Asunto(s)
Reconocimiento Facial , Reconocimiento en Psicología , Humanos , Ojo , Cara , Boca , Reconocimiento Visual de Modelos
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