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Photonic ionogels with dual electrical and optical output have been intensively studied. However, tunable temperature-responsive photonic ionogel assembled by thermosensitive nanogels has not been studied yet. Herein, an innovative approach to fabricate photonic ionogels has been developed for smart wearable devices with tunable temperature sensitivity and structural color. Firstly, poly(isopropylacrylamide-r-phenylmaleanilic acid) P(NIPAm-r-NPMA) nanogels self-assemble into photonic crystals in 2-hydroxyethyl acrylate (HEA), water, and the ionic liquid of 1-ethyl-3-methylimidazolium trifluoromethanesulfonate. And then robust photonic ionogels are developed through a polymerization of 2-hydroxyethyl acrylate crosslinked by poly(ethylene glycol) diacrylate (PEGDA). The incorporation of the ionic liquid, 1-ethyl-3-methylimidazolium trifluoromethanesulfonate, enhances the mechanical strength of photonic ionogels and tunes the temperature-sensitivity of the ionogels, making them adaptable to various environmental conditions. The findings demonstrate that these ionogels can serve dual functions in smart wearable devices, combining electrical and optical signal outputs due to the conductivity of the ionic liquid and structural color from the nanogel assembly. The resultant photonic ionogels exhibit exceptional substrate adhesion, mechanical stability, and fast resilience. More significantly, the nanogels within these ionogels serve as the building blocks of photonic crystals (PCs) endow with angle-independent coloration and enhance stretchability beyond 200 %, while the stretchability of the ionogles without the nanogels is only about 100 %. Our photonic ionogels with tunable temperature-sensitivity and dual outputs will open an avenue to the development of the innovative smart wearable devices.
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Ultraviolet (UV) exposure causes damage to human skin and mucous membranes, resulting in oxidative stress, and can also lead to inflammation of human skin, skin aging, and even diseases such as squamous cell carcinoma and melanoma of the skin. The main means of protection against UV radiation is physical shielding and the use of sunscreen products. Carbon dots as a novel nanomaterial provide a new option for UV protection. In this article, we introduced sulfhydryl groups to synthesize l-cysteine-derived carbon dots (GLCDs) with UV resistance. GLCDs exhibit high-efficiency and excellent UV absorption, achieving 200-400 nm UV absorption (99% UVC, 97% UVB, and 86% UVA) at a low concentration of 0.5 mg/mL. Meanwhile, GLCDs can reduce apoptosis and UVB-induced oxidative damage, increase collagen type I gene expression, and inhibit skin aging in zebrafish. It also inhibits senescence caused by the senescence inducer 2,2'-azobis(2-methylpropionamidine) dihydrochloride and reduces oxidative damage. The above studies show that GLCDs possess efficient broad-spectrum UV absorption, antiphotoaging, and antiaging capabilities, which will have a broad application prospect in UV protection.
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Carbono , Cisteína , Estrés Oxidativo , Puntos Cuánticos , Envejecimiento de la Piel , Rayos Ultravioleta , Pez Cebra , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/efectos de la radiación , Cisteína/química , Cisteína/farmacología , Humanos , Animales , Carbono/química , Envejecimiento de la Piel/efectos de los fármacos , Envejecimiento de la Piel/efectos de la radiación , Puntos Cuánticos/química , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Piel/efectos de los fármacos , Piel/efectos de la radiación , Piel/metabolismoRESUMEN
One of the greatest frequent types of malignancy is gastric cancer (GC). Metastasis, an essential feature of stomach cancer, results in a high rate of mortality and a poor prognosis. However, metastasis biological procedures are not well recognized. Long non-coding RNAs (lncRNAs) have a role in numerous gene regulation pathways via epigenetic modification as well as transcriptional and post-transcriptional control. LncRNAs have a role in a variety of disorders, such as cardiovascular disease, Alzheimer's, and cancer. LncRNAs are substantially related to GC incidence, progression, metastasis and drug resistance. Several research released information on the molecular processes of lncRNAs in GC pathogenesis. By interacting with a gene's promoter or enhancer region to influence gene expression, lncRNAs can operate as an oncogene or a tumor suppressor. This review includes the lncRNAs associated with metastasis of GC, which may give insights into the processes as well as potential clues for GC predicting and tracking.
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CRISPR technologies have revolutionized research areas ranging from fundamental science to translational medicine. CRISPR-based genetic screens offer a powerful platform for unbiased screening in various fields, such as cancer immunology. Immune checkpoint blockade (ICB) therapy has been shown to strongly affect cancer treatment. However, the currently available ICBs are limited and do not work in all cancer patients. Pooled CRISPR screens enable the identification of previously unknown immune regulators that can regulate T-cell activation, cytotoxicity, persistence, infiltration into tumors, cytokine secretion, memory formation, T-cell metabolism, and CD4+ T-cell differentiation. These novel targets can be developed as new immunotherapies or used with the current ICBs as new combination therapies that may yield synergistic efficacy. Here, we review the progress made in the development of CRISPR technologies, particularly technological advances in CRISPR screens and their application in novel target identification for immunotherapy.
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The impact of the long-term trace hydrazine (N2H4) exogenous supplementation on activity of the anaerobic ammonium oxidation (anammox) biofilm was investigated in a moving bed biofilm reactor (MBBR) for mainstream wastewater treatment. The results of this study demonstrated that the addition of 2-5 mg/L N2H4 enhanced anammox biofilm activity, as evidenced by the augmented nitrogen removal rate (NRR), which increased from 113.4 g/(m3·d) to 126.7 g/(m3·d) with the introduction of 2 mg/L N2H4. However, a higher concentration of N2H4 (10 mg/L) suppressed anammox activity, leading to a reduced NRR of 91.5 g/(m3·d). Bioindicators revealed that the long-term addition of 2 mg/L N2H4 fostered the accumulation of anammox bacteria (AnAOB) biomass, elevating the volatile suspended solids (VSS) content by 12%. Moreover, the structural composition of extracellular polymeric substances (EPS) within the biofilm was altered, resulting in enhanced biofilm strength within the reactor. The protective mechanism of the biofilm was activated, and EPS secretion was stimulated by the continuous N2H4 supplementation. The introduction of an excess dosage of N2H4 led to alterations in the microbial communities, ultimately resulting in a decline in the performance of the reactor. These findings collectively illustrate that N2H4, as an intermediate product, can effectively enhance anammox activity within the MBBR for mainstream wastewater treatment. This study contributes to the understanding of the optimization strategies for anammox processes in wastewater treatment systems.
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Biopelículas , Reactores Biológicos , Hidrazinas , Oxidación-Reducción , Eliminación de Residuos Líquidos , Aguas Residuales , Biopelículas/efectos de los fármacos , Reactores Biológicos/microbiología , Hidrazinas/farmacología , Hidrazinas/química , Aguas Residuales/química , Eliminación de Residuos Líquidos/métodos , Bacterias/efectos de los fármacos , Bacterias/metabolismo , Anaerobiosis , Compuestos de Amonio/química , Nitrógeno , Microbiota/efectos de los fármacos , BiomasaRESUMEN
BACKGROUND: In AFP-negative hepatocellular carcinoma patients, markers for predicting tumor progression or prognosis are limited. Therefore, our objective is to establish an optimal predicet model for this subset of patients, utilizing interpretable methods to enhance the accuracy of HCC prognosis prediction. METHODS: We recruited a total of 508 AFP-negative HCC patients in this study, modeling with randomly divided training set and validated with validation set. At the same time, 86 patients treated in different time periods were used as internal validation. After comparing the cox model with the random forest model based on Lasso regression, we have chosen the former to build our model. This model has been interpreted with SHAP values and validated using ROC, DCA. Additionally, we have reconfirmed the model's effectiveness by employing an internal validation set of independent periods. Subsequently, we have established a risk stratification system. RESULTS: The AUC values of the Lasso-Cox model at 1, 2, and 3 years were 0.807, 0.846, and 0.803, and the AUC values of the Lasso-RSF model at 1, 2, and 3 years were 0.783, 0.829, and 0.776. Lasso-Cox model was finally used to predict the prognosis of AFP-negative HCC patients in this study. And BCLC stage, gamma-glutamyl transferase (GGT), diameter of tumor, lung metastases (LM), albumin (ALB), alkaline phosphatase (ALP), and the number of tumors were included in the model. The validation set and the separate internal validation set both indicate that the model is stable and accurate. Using risk factors to establish risk stratification, we observed that the survival time of the low-risk group, the middle-risk group, and the high-risk group decreased gradually, with significant differences among the three groups. CONCLUSION: The Lasso-Cox model based on AFP-negative HCC showed good predictive performance for liver cancer. SHAP explained the model for further clinical application.
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This study aimed to conduct a linguistic validation of all FACE-Q eye module scales in German, and to evaluate the reliability and validity of the scales in patients with blepharoplasty. According to international recommendations, all FACE-Q scales and checklists were translated from English to German. Psychometric testing of blepharoplasty surgery-related scales of translated versions were administered to patients with blepharochalasis or dermatochalasis and a history of blepharoplasty surgery (n = 64; 11 scales) or no history of blepharoplasty surgery (n = 65; seven scales), and to a group of control subjects (n = 64; seven scales). Most of the subscales showed acceptable internal consistency, with Cronbach's alphas ranging from 0.75 to 0.97. Intraclass correlation coefficients were high (0.70-0.92), indicating good reliability, with total values of 0.63 (95% CI 0.46-0.76) and 0.68 (95% CI 0.53-0.80) for the upper eyelid and social function scores, respectively. There was good discriminability between pre- and post-blepharoplasty patients and normal subjects (p < 0.05). The German-language version of the FACE-Q eye module is a successfully validated and helpful tool for assessing outcomes after blepharoplasty surgery, especially with respect to 'satisfaction with overall facial appearance', 'psychological well-being, social function', 'decision satisfaction, outcome satisfaction', and 'early-life impact recovery'.
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Building structures are exposed to direct sunlight for a long time, accumulating a large amount of low-grade thermal energy, which aggravates environmental pollution and energy consumption. Thermoelectric cement-based composites can realize the interconversion of thermal and electrical energy, showing great potential benefits in large-scale heat collection and energy conversion. Although a lot of exploration and research has been carried out on the thermoelectric properties of cement-based composites reinforced with carbon materials, the contribution of the characteristics of carbon materials, such as the graphitization degree, to the thermoelectric properties of cement-based composites is still unclear. In this article, the graphitization degree of expanded graphite (EG) was modulated by etching EG with an acid solution. The low graphitization degree improves the effective mass of carriers and aggravates the electron and phonon scattering at the interface of EG/cement-based composites. Low thermal conductivity was obtained while increasing the Seebeck coefficient of EG/cement-based composites. The power factor (17.1 µW m-1 K-2) and thermoelectric figure of merit (2.95 × 10-3) of the sample are increased by 18.6 times and 44.2 times, respectively, achieving the highest thermoelectric performance in cement-based composites reinforced with carbon materials. This study provides a direction for improving the thermoelectric properties of cement-based composites by structural regulation of carbon materials.
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Climate warming poses a significant threat to global crop production and food security. However, our understanding of the molecular mechanisms governing thermoresponsive development in crops remains limited. Here we report that the auxiliary subunit of N-terminal acetyltransferase A (NatA) in rice OsNAA15 is a prerequisite for rice thermoresponsive growth. OsNAA15 produces two isoforms OsNAA15.1 and OsNAA15.2, via temperature-dependent alternative splicing. Among the two, OsNAA15.1 is more likely to form a stable and functional NatA complex with the potential catalytic subunit OsNAA10, leading to a thermoresponsive N-terminal acetylome. Intriguingly, while OsNAA15.1 promotes plant growth under elevated temperatures, OsNAA15.2 exhibits an inhibitory effect. We identified two glycolate oxidases (GLO1/5) as major substrates from the thermoresponsive acetylome. These enzymes are involved in hydrogen peroxide (H2O2) biosynthesis via glycolate oxidation. N-terminally acetylated GLO1/5 undergo their degradation through the ubiquitin-proteasome system. This leads to reduced reactive oxygen species (ROS) production, thereby promoting plant growth, particularly under high ambient temperatures. Conclusively, our findings highlight the pivotal role of N-terminal acetylation in orchestrating the glycolate-mediated ROS homeostasis to facilitate thermoresponsive growth in rice.
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Glicolatos , Homeostasis , Oryza , Proteínas de Plantas , Especies Reactivas de Oxígeno , Temperatura , Oryza/metabolismo , Oryza/crecimiento & desarrollo , Oryza/efectos de los fármacos , Oryza/genética , Acetilación , Especies Reactivas de Oxígeno/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Glicolatos/metabolismo , Peróxido de Hidrógeno/metabolismo , Proteolisis/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Oxidorreductasas de Alcohol/metabolismoRESUMEN
OBJECTIVE: To quantitatively assess the periocular asymmetry and investigate its sex and age-related differences in a Caucasian population using three-dimensional (3D) stereophotogrammetry. METHOD: Standardized 3D photos of the periocular region of 301 Caucasians were taken using the VECTRA M3 3D Imaging System. Standardized landmarks were positioned, and data measurements in the periocular region were obtained from these images using VAM software and assessed using intraclass correlation coefficients (ICC) for reliability. Absolute differences and asymmetry index between the right and the left periocular region were calculated with a focus on gender and age-related differences. RESULT: Fissure height asymmetry was positively correlated with age (p < 0.01). Furthermore, reflex distance asymmetry was positively correlated with age in the elderly group (p < 0.05). Absolute differences of upper eyelid crease were 0.65 ± 0.79 mm for females and 0.90 ± 0.94 mm for males (p < 0.05). In the elderly group, the absolute differences of reflex distance were 0.664 ± 0.471 mm for males and 0.470 ± 0.408 mm for females (p < 0.05), while the absolute differences of fissure height were 0.619 ± 0.469 mm and 0.436 ± 0.372 mm, respectively (p < 0.05). All measurements had an inter-rater ICC and intra-rater ICC between 0.761 and 0.957. CONCLUSION: Periocular asymmetry is more prominent in older and male people. 3D photogrammetry is a reliable tool to detect periocular asymmetry and might provide an accurate and effective reference for periocular cosmetic, plastic, and reconstructive surgery in the clinical routine. LEVEL OF EVIDENCE I: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors. www.springer.com/00266 .
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Purpose: To explore the role of ultraviolet radiation (UVR) in the occurrence and development of various ocular malignancies. Methods: In this article, we retrieved ocular malignancy data from the Global Cancer Observatory (GCO) and performed correlation analysis with the global UV index and sunshine duration. We searched for associated studies using the following databases: Embase, Pubmed, Cochrane Library, and Google Scholar. We conducted the literature by searching the Mesh terms denoting an exposure of interest ("UV radiation", "ultraviolet rays", and "ocular malignancies", All studies included are published until December 30, 2023 without language restrictions. Results: The mechanisms and epidemiological statistics of UVR on the onset and progression of eyelid malignancies are the most studied and clear. The role of UVR in conjunctival melanoma is similar to that in eyelid melanoma. The relationship between uveal melanoma and UVR is controversial, however, it may have at least a certain impact on its prognosis. UVR causes ocular surface squamous neoplasia by further activating HPV infection. Conclusions: UVR is a decisive risk factor for ocular malignancies, but the incidence of ultraviolet-induced tumors is also affected by many other factors. A correct and comprehensive understanding of the mechanisms of UVR in the pathogenesis of ocular malignant tumors can provide patients with more effective and selective immune regulation strategies.
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Thermally-induced in-situ gelation of polymers and nanogels is of significant importance for injectable non-invasive tissue engineering and delivery systems of drug delivery system. In this study, we for the first time demonstrated that the interpenetrating (IPN) nanogel with two networks of poly (N-isopropylacrylamide) (PNIPAM) and poly (N-Acryloyl-l-phenylalanine) (PAphe) underwent a reversible temperature-triggered sol-gel transition and formed a structural color gel above the phase transition temperature (Tp). Dynamic light scattering (DLS) studies confirmed that the Tp of IPN nanogels are the same as that of PNIPAM, independent of Aphe content of the IPN nanogels at pH of 6.5 â¼ 7.4. The rheological and optical properties of IPN nanogels during sol-gel transition were studied by rheometer and optical fiber spectroscopy. The results showed that the gelation time of the hydrogel photonic crystals assembled by IPN nanogel was affected by temperature, PAphe composition, concentration, and sequence of interpenetration. As the temperature rose above the Tp, the Bragg reflection peak of IPN nanogels exhibited blue shift due to the shrinkage of IPN nanogels. In addition, these colored IPN nanogels demonstrated good injectability and had no obvious cytotoxicity. These IPN nanogels will open an avenue to the preparation and thermally-induced in-situ gelation of novel NIPAM-based nanogel system.
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PURPOSE: To define the regular upper eyelid anatomy and their changes during dynamic motion using ultrasonographically depicted structures. DESIGN: A cross-sectional study. METHODS: High-resolution ultrasound biomicroscopy (50MHz) was performed on 84 upper eyelids of 42 healthy volunteers without evidence of eyelid conditions. The skin-orbicularis oculi complex (SOOC), levator aponeurosis, and Müller's muscle-conjunctival complex were imaged. The thickness of these structures was measured in primary gaze and downgaze positions. RESULTS: SOOC and levator aponeurosis thickness was bigger with eyes open than with eyes closed (p < 0.01). With eyes closed, the thickness of SOOC on the pupillary midline and levator aponeurosis was positively correlated with age (p < 0.05, p < 0.01, respectively), and the thickness of levator aponeurosis and SOOC on the pupil midline was also positively correlated with BMI index (p < 0.05). Similarly, SOOC thickness on the medial and lateral canthus line is also positively correlated with BMI index and age (p < 0.05, p < 0.01, respectively). As for the differences between genders, the mean thickness of SOOC and levator aponeurosis was statistically different (p < 0.05, respectively). The magnitude of levator aponeurosis thickness in men varied more than in women in different ocular positions (p < 0.05). All measurements had an intramethod between 0.624 and 0.792, and inter-rater ICC and intrarater ICC between 0.748 and 0.850. CONCLUSIONS: Ultrasound biomicroscopy represents a noninvasive tool for the visualization of upper eyelid morphology. Expanding its application can help to understand the dynamics of upper eyelid physiological movement, aging, and disease research in different populations and evaluate surgical outcomes.
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Párpados , Microscopía Acústica , Humanos , Masculino , Femenino , Párpados/diagnóstico por imagen , Párpados/anatomía & histología , Párpados/fisiología , Microscopía Acústica/métodos , Adulto , Estudios Transversales , Persona de Mediana Edad , Adulto Joven , Anciano , Valores de ReferenciaRESUMEN
When faced with a conflict or dilemma, we tend to postpone or even avoid making a decision. This phenomenon is known as decisional procrastination. Here, we investigated the neural correlates of this phenomenon, in particular the parahippocampal gyrus (PHG) that has previously been identified in procrastination studies. In this study, we applied an individual difference approach to evaluate participants' spontaneous neural activity in the PHG and their decisional procrastination levels, assessed outside the fMRI scanner. We discovered that the fractional amplitude of low-frequency fluctuations (fALFF) in the caudal PHG (cPHG) could predict participants' level of decisional procrastination, as measured by the avoidant decision-making style. Importantly, participants' self-esteem mediated the relationship between the cPHG and decisional procrastination, suggesting that individuals with higher levels of spontaneous activity in the cPHG are likely to have higher levels of self-esteem and thus be more likely to make decisions on time. In short, our study broadens the PHG's known role in procrastination by demonstrating its link with decisional procrastination and the mediating influence of self-esteem, underscoring the need for further exploration of this mediation mechanism.
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Background: Telemedicine technology is a rapidly developing field that shows immense potential for improving medical services. In palliative care, informal caregivers assume the primary responsibility in patient care and often face challenges such as increased physical and mental stress and declining health. In such cases, telemedicine interventions can provide support and improve their health outcomes. However, research findings regarding the use of telemedicine among informal caregivers are controversial, and the efficacy of telemedicine remains unclear. Objective: This study aimed to evaluate the impacts of telemedicine on the burden, anxiety, depression, and quality of life of informal caregivers of patients in palliative care. Methods: A systematic literature search was conducted using the PubMed, Embase, Web of Science, CENTRAL, PsycINFO, CINAHL Plus with Full Text, CBM, CNKI, WanFang, and VIP databases to identify relevant randomized controlled trials published from inception to March 2023. Two authors independently screened the studies and extracted the relevant information. The methodological quality of the included studies was assessed using the Cochrane risk-of-bias tool. Intervention effects were estimated and sensitivity analysis was conducted using Review Manager 5.4, whereas 95% prediction intervals (PIs) were calculated using R (version 4.3.2) and RStudio. Results: A total of 9 randomized controlled trials were included in this study. The meta-analysis indicated that telemedicine has reduced the caregiving burden (standardized mean differences [SMD] -0.49, 95% CI -0.72 to -0.27; P<.001; 95% PI -0.86 to -0.13) and anxiety (SMD -0.23, 95% CI -0.40 to -0.06; P=.009; 95% PI -0.98 to 0.39) of informal caregivers; however, it did not affect depression (SMD -0.21, 95% CI -0.47 to 0.05; P=.11; 95% PI -0.94 to 0.51) or quality of life (SMD 0.35, 95% CI -0.20 to 0.89; P=.21; 95% PI -2.15 to 2.85). Conclusions: Although telemedicine can alleviate the caregiving burden and anxiety of informal caregivers, it does not significantly reduce depression or improve their quality of life. Further high-quality, large-sample studies are needed to validate the effects of telemedicine. Furthermore, personalized intervention programs based on theoretical foundations are required to support caregivers.
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Cuidados Paliativos , Telemedicina , Humanos , Cuidadores , Calidad de Vida , Estrés Psicológico , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
To effectively inhibit the retrogradation of staple foods, the effects of maltotetraose-forming amylase(G4-amylase) on the short and long-term retrogradation of different staple starches such as rice starch (RS), wheat starch (WS), potato starch (PS) were studied. The results indicated that G4-amylase decreased the content of amylose. Amylose contents (21.09%) of WSG4 were higher than that (14.82%) of RSG4 and (13.13%) of PSG4. WS had the most obvious change in the chain length distribution of amylopectin. A chains decreased by 18.99% and the B1 chains decreased by 12.08% after G4-amylase treatment. Compared to RS (662 cP) and WS (693 cP), the setback viscosity of RSG4 (338 cP) and WSG4 (385 cP) decreased. Compared to RS (0.41), WS (0.45), and PS (0.51), the long-term retrogradation rate of RSG4 (0.33), WSG4 (0.31), and PSG4 (0.38) significantly reduced. It indicated that G4-amylase significantly inhibited the long-term retrogradation of WS, followed by RS and PS.
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Amilasas , Maltosa/análogos & derivados , Oryza , Solanum tuberosum , Almidón , Triticum , Almidón/química , Amilasas/química , Amilasas/metabolismo , Triticum/química , Viscosidad , Solanum tuberosum/química , Oryza/química , Amilosa/química , Amilosa/análisis , Maltosa/química , BiocatálisisRESUMEN
Thermally induced physical hydrogels formed through the sol-gel transition of nanogels usually lose structural color above phase transition temperature (Tp). Herein, temperature/pH/redox-responsive nanogels that undergo sol-gel transition still keep structural colors above the Tp have been synthesized and studied. N-isopropylacrylamide (NIPAm) was copolymerized with N-tert-butylacrylamide (TBA) and N-acrylamido-l-phenylalanine (Aphe) to form P(NIPAm/TBA/Aphe) nanogel crosslinked with N,N'-bis(acryloyl)cystine (BISS) (referred to as PNTA-BISS). PNTA-BISS nanogel with a broad range of biodegradable crosslinker BISS content can achieve a reversible sol-gel transition above the Tp, surprisingly, while PNTA nanogels with a comparable content of biodegradable N,N'-Bis(acryloyl)cystam (BAC) crosslinker (referred to as PNTA-BAC) didn't form sol-gel transition. Although BISS and BAC possess same disulfide bonds with redox properties, BISS, unlike BAC, is water-soluble and features two carboxyl groups. The mechanism by which PNTA-BISS nanogels form hydrogel photonic crystals has been deeply explored with temperature-variable NMR. The results showed the introduction of Aphe with both steric hindrance and carboxyl groups greatly slowed down the shrinkage of PNTA-BISS nanogels. Therefore, PNTA-BISS nanogels can form sol-gel transition and further structural color of hydrogel photonic crystals due to carboxyl groups above the Tp. Furthermore, the properties of biodegradable hydrogel photonic crystals above the Tp were investigated for the first time, attributed to the presence of the strong reducing agent 1,4-dithiothreitol (DTT). When loaded with doxorubicin (DOX), PNTA-BISS exhibited favorable degradation properties under the influence of DTT. In summary, the PNTA-BISS nanogel, in addition to its in-situ gelation capabilities, demonstrated degradability, potentially providing a novel nanoplatform for applications in drug delivery, biotechnology, and related fields.
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Hidrogeles , Polietilenglicoles , Nanogeles , Hidrogeles/química , PolietileneiminaRESUMEN
Sulfur in nature consists of two abundant stable isotopes, with two more neutrons in the heavy one (34S) than in the light one (32S). The two isotopes show similar physicochemical properties and are usually considered an integral system for chemical research in various fields. In this work, a model study based on a Li-S battery was performed to reveal the variation between the electrochemical properties of the two S isotopes. Provided with the same octatomic ring structure, the cyclo-34S8 molecules form stronger S-S bonds than cyclo-32S8 and are more prone to react with Li. The soluble Li polysulfides generated by the Li-34S conversion reaction show a stronger cation-solvent interaction yet a weaker cation-anion interaction than the 32S-based counterparts, which facilitates quick solvation of polysulfides yet hinders their migration from the cathode to the anode. Consequently, the Li-34S cell shows improved cathode reaction kinetics at the solid-liquid interface and inhibited shuttle of polysulfides through the electrolyte so that it demonstrates better cycling performance than the Li-32S cell. Based on the varied shuttle kinetics of the isotopic-S-based polysulfides, an electrochemical separation method for 34S/32S isotope is proposed, which enables a notably higher separation factor than the conventional separation methods via chemical exchange or distillation and brings opportunities to low-cost manufacture, utilization, and research of heavy chalcogen isotopes.
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To investigate the effect of oil additives on improving the water resistance of corn starch straws, corn oil (CO), soybean oil (SO), rapeseed oil (RO), peanut oil (PO), lard (LD) and coconut oil (CCO) were chosen and compared the structure and properties of starch straws with different oil additives. Corn starch straws (CS), and starch straws supplemented with CO, SO, RO, PO, LD and CCO were prepared by thermoplastic extrusion. The results showed that the incorporation of oils effectively enhanced the water resistance of starch straws such as water absorption, water solubility and water swelling performance. Meanwhile, the flexural strength of starch straws significantly increased. There was no significant linear relationship among starch chain length, oil unsaturation and straw performance. Among seven starch straws, S-SO had the strongest hydrogen bond interaction (3289 cm-1) and relaxation time (0.96 ms). The S-CO had the highest relative crystallinity (16.82 %) and degree of double helix (1.535), hence resulting in the lowest water absorption and solubility values, the highest flexural strength (23.43 MPa), the highest ΔT value (9.93 °C) and ΔH value (4.79 J/g). S-RO had the highest thermal transition temperatures.
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Almidón , Zea mays , Almidón/química , Zea mays/química , Agua/química , Aceite de Soja , Fenómenos Químicos , Aceite de Brassica napus , Aceite de MaízRESUMEN
Ultrasound elastography (USE) is a promising tool for tissue characterization as several diseases result in alterations of tissue structure and composition, which manifest as changes in tissue mechanical properties. By imaging the tissue response to an applied mechanical excitation, USE mimics the manual palpation performed by clinicians to sense the tissue elasticity for diagnostic purposes. Next to elasticity, viscosity has recently been investigated as an additional, relevant, diagnostic biomarker. Moreover, since biological tissues are inherently viscoelastic, accounting for viscosity in the tissue characterization process enhances the accuracy of the elasticity estimation. Recently, methods exploiting different acquisition and processing techniques have been proposed to perform ultrasound viscoelastography. After introducing the physics describing viscoelasticity, a comprehensive overview of the currently available USE acquisition techniques is provided, followed by a structured review of the existing viscoelasticity estimators classified according to the employed processing technique. These estimators are further reviewed from a clinical usage perspective, and current outstanding challenges are discussed.