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Hierarchical polymer structures have garnered widespread application across various fields owing to their distinct surface properties and expansive surface areas. Conventional hierarchical polymer structures, however, often lack postfabrication scalability and spatial selectivity. In this study, we propose a novel strategy to prepare light-assisted hierarchical polymer structures using azopolymers (PAzo), the breath figure method, and anodic aluminum oxide (AAO) templates. Initially, the breath figure PAzo films are prepared by dripping a PAzo chloroform solution onto glass substrates in a high-humidity environment. The AAO templates are then placed on the breath figure PAzo film. Upon ultraviolet (UV) light exposure, the azobenzene groups in the azopolymers undergo trans-cis photoisomerization. This process causes the glass transition temperature (Tg) of the PAzo to become lower than room temperature, allowing the azopolymer to enter the nanopores of the AAO templates. The hierarchical azopolymer structures are then formed by using a sodium hydroxide solution to remove the templates. Furthermore, exploring the effects of PAzo concentration and UV light exposure duration on the film morphology reveals optimized conditions for hierarchical structure formation. Additionally, the water contact angles of these polymer structures are measured. The hierarchical PAzo structures exhibit higher hydrophobicity compared with the flat PAzo films and the PAzo breath figure films. Finally, patterned breath figure films can be prepared using designed photomasks, demonstrating the method's capability for spatial selectivity.
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In recent years, liquid crystal materials have drawn great interest because of their wide range of applications. Among various thermochromic materials, cholesteric liquid crystalline (CLC) materials have been well studied and reported. CLC materials have the advantages of ready manipulation and multiple color transitions. For the further development of smart clothing and wearable electronics, however, the incorporation of CLC materials into polymers still remains challenging. The difficulties lie in the prevention of leakage of CLC and retention of the cholesteric liquid crystalline phase. In this work, we demonstrate a versatile nonsolvent and phase separation method using polar solvents to incorporate CLC microspheres into polymer matrix. Poly(vinyl alcohol) (PVA), a water-soluble polymer, is chosen as the polymer because of its high transparency and ease to handle. Using spin-coating and wet spinning techniques, PVA/CLC films and fibers can be fabricated. The formation of CLC microspheres in the polymer matrix is characterized through optical and polarized microscopy. Compared with the CLC films, the PVA/CLC composites demonstrate superior thermal stability. Moreover, both PVA/CLC films and fibers exhibit good color stability from the electrical tests. This work provides an effective strategy to prepare polymer/CLC composites, paving a wide avenue toward applications in smart textiles, display technologies, and medical devices.
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Despite significant advancements, current self-healing materials often suffer from a compromise between mechanical robustness and functional performance, particularly in terms of conductivity and responsiveness to environmental stimuli. Addressing this issue, the research introduces a self-healable and conductive copolymer, poly(ionic liquid-co-acrylic acid) (PIL-co-PAA), synthesized through free radical polymerization, and further optimized by incorporating thermoplastic polyurethane (TPU). This combination leverages the unique properties of each component, especially ion-dipole interactions and hydrogen bonds, resulting in a material that exhibits exceptional self-healing abilities and demonstrates enhanced mechanical properties and electrical conductivity. Moreover, the PIL-co-PAA/TPU films showcase alkaline-responsive behavior, a feature that broadens their applicability in dynamic environments. Through systematic characterization, including thermogravimetric analysis, tensile testing, and electrical properties measurements, the mechanisms behind the improved performance and functionality of these films are elucidated. The conductivities and ultimate tensile strength (σuts) of the PIL-co-PAA/TPU films regain 80% under 8 h healing process. To extend the applications for wearable devices, the self-healing properties of commercial cotton fabrics coated with the self-healable PIL-co-PAA are also investigated, demonstrating both self-healing and electrical properties. This study advances the understanding of self-healable conductive polymers and opens new avenues for their application in wearable technology.
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Multiresponsive materials with reversible and durable characteristics are indispensable because of their promising applications in environmental change detections. To fabricate multiresponsive materials in mass production, however, complex reactions and impractical situations are often involved. Herein, a dual responsive (light and pH) spiropyran-based smart sensor fabricated by a simple layer-by-layer (LbL) assembly process from upcycled thermoplastic polyester elastomer (TPEE) materials derived from recycled polyethylene terephthalate (r-PET) is proposed. Positively charged chitosan solutions and negatively charged merocyanine-COOH (MC-COOH) solutions are employed in the LbL assembly technique, forming the chitosan-spiropyran deposited TPEE (TPEE-CH-SP) film. Upon UV irradiation, the spiropyran-COOH (SP-COOH) molecules on the TPEE-CH-SP film undergo the ring-opening isomerization, along with an apparent color change from colorless to purple, to transform into the MC-COOH molecules. By further exposing the TPEE-CH-MC film to hydrogen chloride (HCl) and nitric acid (HNO3) vapors, the MC-COOH molecules can be transformed into protonated merocyanine-COOH (MCH-COOH) with the simultaneous color change from purple to yellow.
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OBJECTIVE: This study aimed to systematically review the worldwide second-stage cesarean delivery rate concerning pre-second-stage cesarean delivery and assisted vaginal birth rates. DATA SOURCES: PubMed, Medline Ovid, EBSCOhost, Embase, Scopus, and Google Scholar were queried from inception to February 2023, with the following terms: "full dilatation," "second stage," and "cesarean," with their word variations. Furthermore, an additional cohort of 353,434 cases from our recently published study was included. STUDY ELIGIBILITY CRITERIA: Only original studies that provided sufficient information on the number of pre-second-stage cesarean deliveries, second-stage cesarean deliveries, and vaginal births were included for the calculation of different modes of delivery. Systemic reviews, meta-analyses, or case reports were excluded. METHODS: Study identification and data extraction were independently performed by 2 authors. Selected studies were categorized on the basis of parity, study period, and geographic regions for comparison. RESULTS: A total of 25 studies were included. The overall pre-second-stage cesarean delivery rate, the second-stage cesarean delivery rate, and the second-stage cesarean delivery-to-assisted vaginal birth ratio were 17.94%, 2.65%, and 0.19, respectively. Only 5 studies described singleton, term, cephalic presenting pregnancies of nulliparous women, and their second-stage cesarean delivery rates were significantly higher than those studies with cohorts of all parity groups (4.50% vs 0.83%; P<.05). In addition, the second-stage cesarean delivery rate showed a secular increase across 2009 (0.70% vs 1.05%; P<.05). Moreover, it was the highest among African studies (5.14%) but the lowest among studies from East Asia and South Asia (0.94%). The distributions of second-stage cesarean delivery rates of individual studies and subgroups were shown with that of pre-second-stage cesarean delivery and assisted vaginal birth using the bubble chart. CONCLUSION: The overall worldwide pre-second-stage cesarean delivery rate was 17.94%, the second-stage cesarean delivery rate was 2.65%, and the second-stage cesarean delivery-to-assisted vaginal birth ratio was 0.19. The African studies had the highest second-stage cesarean delivery rate (5.14%) and second-stage cesarean delivery-to-assisted vaginal birth ratio (1.88), whereas the studies from East Asia and South Asia were opposite (0.94% and 0.11, respectively).
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Nanoplastics (NPs) have been identified as an emerging concern for the environment and our food chains in recent years. Monitoring the concentration and size of nanoplastics is essential to assess the potential risks that nanoplastic particles may pose. In this study, we presented a multi-technique based analytical platform to identify, characterize and quantify nanoplastics in water samples through a combination of sample pre-concentration, asymmetric flow field-flow fractionation coupled with multi-angle light scattering (AF4-MALS) and pyrolysis-GC/MS (Py-GC/MS). Models for predicting NPs concentration and particle number in unknown samples were established and validated using NPs standards of known size and AF4-MALS response. Py-GC/MS was applied for further identification of polymer type and quantification of mass concentration. Filtration conditions for pre-concentration were optimized to ensure a high recovery rate with minimal effect on original particle size. The addition of 0.05% SDS prior to filtration, using controlled filtration procedures, effectively improved the recovery. Furthermore, this study demonstrates the application of the analytical platform for the characterization and quantification of different nanoparticles (e.g. spiked PMMA and PS NPs) in the size range 60 nm-350 nm with detection limits down to 0.01 ppm in water samples. The established analytical platform can fill an analytical gap by offering a solution for quantifying size-resolved mass concentrations of nanoplastics and providing comprehensive data on size distribution, particle number and mass quantification with high sensitivity for detection.
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BACKGROUND: The incidence of second stage cesarean delivery has been rising globally because of the failure or the anticipated difficulty of performing instrumental delivery. Yet, the best way to interpret the figure and its optimal rate remain to be determined. This is because it is strongly influenced by the practice of other 2 modes of birth, namely cesarean delivery performed before reaching the second stage and assisted vaginal birth during the second stage. In this regard, a bubble chart that can display 3-dimensional data through its x-axis, y-axis, and the size of each plot (presented as a bubble) may be a suitable method to evaluate the relationship between the rates of these 3 modes of births. OBJECTIVE: This study aimed to conduct an epidemiologic study on the incidence of second stage cesarean deliveries rates among >300,000 singleton term births in 10 years from 8 obstetrical units and to compare their second stage cesarean delivery rates in relation to their pre-second stage cesarean delivery rates and assisted vaginal birth rates using a bubble chart. STUDY DESIGN: The territory-wide birth data collected between 2009 and 2018 from all 8 public obstetrical units (labelled as A to H) were reviewed. The inclusion criteria were all singleton pregnancies with cephalic presentation that were delivered at term (≥37 weeks' gestation). Pre-second stage cesarean delivery rate was defined as all elective cesarean deliveries and those emergency cesarean deliveries that occurred before full cervical dilatation was achieved as a proportion of the total number of births. The second stage cesarean delivery rate and assisted vaginal birth rate were calculated according to the respective mode of delivery as a proportion of the number of cases that reached full cervical dilatation. The rates of these 3 modes of births were compared among the parity groups and among the 8 units. Using a bubble chart, each unit's second stage cesarean delivery rate (y-axis) was plotted against its pre-second stage cesarean delivery rate (x-axis) as a bubble. Each unit's second stage cesarean delivery to assisted vaginal birth ratio was represented by the size of the bubble. RESULTS: During the study period, a total of 353,434 singleton cephalic presenting term pregnancies were delivered in the 8 units, and 180,496 (51.1%) were from nulliparous mothers. When compared with the multiparous group, the nulliparous group had a significantly lower pre-second stage cesarean delivery rate (18.58% vs 21.26%; P<.001) but a higher second stage cesarean delivery rate (0.79% vs 0.22%; P<.001) and a higher assisted vaginal birth rate (17.61% vs 3.58%; P<.001). Using the bubble of their averages as a reference point in the bubble chart, the 8 units' bubbles were clustered into 5 regions indicating their differences in practice: unit B and unit H were close to the average in the center. Unit A and unit F were at the upper right corner with a higher pre-second stage cesarean delivery rate and second stage cesarean delivery rate. Unit D and unit E were at the opposite end. Unit C was at the upper left corner with a low pre-second stage cesarean delivery rate but a high second stage cesarean delivery rate, whereas unit G was at the opposite end. Unit C and unit G were also in the extremes in terms of pre-second stage cesarean delivery to assisted vaginal birth ratio (0.09 and 0.01, respectively). Although some units seemed to have very similar second stage cesarean delivery rates, their obstetrical practices were differentiated by the bubble chart. CONCLUSION: The second stage cesarean delivery rate must be evaluated in the context of the rates of pre-second stage cesarean delivery and assisted vaginal birth. A bubble chart is a useful method for analyzing the relationship among these 3 variables to differentiate the obstetrical practice between different units.
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Living in the global-changing era, intelligent and eco-friendly electronic components that can sense the environment and recycle or reprogram when needed are essential for sustainable development. Compared with solid-state electronics, composite hydrogels with multi-functionalities are promising candidates. By bridging the self-assembly of azobenzene-containing supramolecular complexes and MXene nanosheets, we fabricate a MXene-based composite gel, namely MXenegel, with reversible photo-modulated phase behavior. The MXenegel can undergo reversible liquefication and solidification under UV and visible light irradiations, respectively, while maintaining its conductive nature unchanged, which can be integrated into traditional solid-state circuits. The strategy presented in this work provides an example of light-responsive conducting material via supramolecular bridging and demonstrates an exciting platform for functional soft electronics.
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Stimuli-responsive ion nanochannels have attracted considerable attention in various fields because of their remote controllability of ionic transportation. For photoresponsive ion nanochannels, however, achieving precise regulation of ion conductivity is still challenging, primarily due to the difficulty of programmable structural changes in confined environments. Moreover, the relationship between noncontact photo-stimulation in nanoscale and light-induced ion conductivity has not been well understood. In this work, a versatile design for fabricating guard cell-inspired photoswitchable ion channels is presented by infiltrating azobenzene-cross-linked polymer (AAZO-PDAC) into nanoporous anodic aluminum oxide (AAO) membranes. The azobenzene-cross-linked polymer is formed by azobenzene chromophore (AAZO)-cross-linked poly(diallyldimethylammonium chloride) (PDAC) with electrostatic interactions. Under UV irradiation, the trans-AAZO isomerizes to the cis-AAZO, causing the volume compression of the polymer network, whereas, in darkness, the cis-AAZO reverts to the trans-AAZO, leading to the recovery of the structure. Consequently, the resultant nanopore sizes can be manipulated by the photomechanical effect of the AAZO-PDAC polymers. By adding ionic liquids, the ion conductivity of the light-driven ion nanochannels can be controlled with good repeatability and fast responses (within seconds) in multiple cycles. The ion channels have promising potential in the applications of biomimetic materials, sensors, and biomedical sciences.
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Atomically thin oxide semiconductors are emerging as potential materials for their potentiality in monolithic 3D integration and sensor applications. In this study, a charge transfer method employing viologen, an organic compound with exceptional reduction potential among n-type organics, is presented to modulate the carrier concentration in atomically thin In2O3 without the need of annealing. This study highlights the critical role of channel thickness on doping efficiency, revealing that viologen charge transfer doping is increasingly pronounced in thinner channels owing to their increased surface-to-volume ratio. Upon viologen doping, an electron sheet density of 6.8 × 1012 cm-2 is achieved in 2 nm In2O3 back gate device while preserving carrier mobility. Moreover, by the modification of the functional groups, viologens can be conveniently removed with acetone and an ultrasonic cleaner, making the viologen treatment a reversible process. Based on this doping scheme, we demonstrate an n-type metal oxide semiconductor inverter with viologen-doped In2O3, exhibiting a voltage gain of 26 at VD = 5 V. This complementary pairing of viologen and In2O3 offers ease of control over the carrier concentration, making it suitable for the next-generation electronic applications.
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Human skin is stably colonized by a distinct microbiota that functions together with epidermal cells to maintain a protective physical barrier. Staphylococcus, a prominent genus of the skin microbiota, participates in colonization resistance, tissue repair, and host immune regulation in strain-specific manners. To unlock the potential of engineering skin microbial communities, we aim to characterize the diversity of this genus within the context of the skin environment. We reanalyzed an extant 16S rRNA amplicon dataset obtained from distinct body sites of healthy volunteers, providing a detailed biogeographic depiction of staphylococcal species that colonize our skin. S. epidermidis, S. capitis, and S. hominis were the most abundant staphylococcal species present in all volunteers and were detected at all body sites. Pan-genome analysis of isolates from these three species revealed that the genus-core was dominated by central metabolism genes. Species-restricted-core genes encoded known host colonization functions. The majority (~68%) of genes were detected only in a fraction of isolate genomes, underscoring the immense strain-specific gene diversity. Conspecific genomes grouped into phylogenetic clades, exhibiting body site preference. Each clade was enriched for distinct gene sets that are potentially involved in site tropism. Finally, we conducted gene expression studies of select isolates showing variable growth phenotypes in skin-like medium. In vitro expression revealed extensive intra- and inter-species gene expression variation, substantially expanding the functional diversification within each species. Our study provides an important resource for future ecological and translational studies to examine the role of shared and strain-specific staphylococcal genes within the skin environment.
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Piel , Staphylococcus , Humanos , Staphylococcus/genética , Filogenia , ARN Ribosómico 16S/genética , ARN Ribosómico 16S/metabolismo , Staphylococcus epidermidis/genética , GenómicaRESUMEN
Introduction: Healthcare integration has become prevalent as health systems manage a growing population of older adults with multi-morbid conditions. The integrated general hospital (IGH) is the latest example of how services can be remodelled to achieve greater care integration. Methods: We conducted a mixed-method evaluation to identify factors impacting the implementation and effectiveness of the IGH model. Data were collected through in-depth interviews (n = 15) and focus group discussions (n = 8 groups) with hospital staff, and a staff survey (n = 226). Results: Staff perceived improvements in clinical practice and better clinical outcomes for patients. The care model empowered nursing and allied health staff through a more collegial team structure. However, staff reported an unequal workload distribution; a third reported burnout; and some observed inconsistencies between leaders' aspirations for IGH and what was happening on the ground. For IGH to sustain, staff's education on the IGH model needs to be improved. Further examination of work processes is recommended to boost staff morale and prevent burnout. Conclusion: Overall, IGH provided better integrated, team-based care. The model challenged traditional team structures and empowered staff to expand their roles and responsibilities. Policymakers could consider the IGH model a successful approach for integrating services across the care continuum.
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The complex interplay between microbiota and immunity is important to human health. To explore how altered adaptive immunity influences the microbiome, we characterize skin, nares, and gut microbiota of patients with recombination-activating gene (RAG) deficiency-a rare genetically defined inborn error of immunity (IEI) that results in a broad spectrum of clinical phenotypes. Integrating de novo assembly of metagenomes from RAG-deficient patients with reference genome catalogs provides an expansive multi-kingdom view of microbial diversity. RAG-deficient patient microbiomes exhibit inter-individual variation, including expansion of opportunistic pathogens (e.g., Corynebacterium bovis, Haemophilus influenzae), and a relative loss of body site specificity. We identify 35 and 27 bacterial species derived from skin/nares and gut microbiomes, respectively, which are distinct to RAG-deficient patients compared to healthy individuals. Underscoring IEI patients as potential reservoirs for viral persistence and evolution, we further characterize the colonization of eukaryotic RNA viruses (e.g., Coronavirus 229E, Norovirus GII) in this patient population.
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Microbioma Gastrointestinal , Microbiota , Humanos , Microbiota/genética , Microbioma Gastrointestinal/genética , Piel , MetagenomaRESUMEN
Exploring stimuli-responsive ion-conductive materials is a challenging task, but it has gained increasing attention because of their enormous potential applications in actuators, sensors, and smart electronics. Here, we demonstrate a distinctive photoresponsive ion-conductive device that utilizes azobenzene-based ionic liquids ([AzoCnMIM][Br], where n = 2, 6, and 10), confined in nanochannels of anodic aluminum oxide (AAO) templates for photoisomerization. The structure of [AzoCnMIM][Br] comprises photoresponsive and hydrophobic azobenzene moieties, hydrophilic imidazolium cations, and negatively charged bromide ions. Therefore, [AzoCnMIM][Br] can form micelles and exhibit photoresponsive ion conductivities. The nanochannels of AAO templates exhibit a confinement effect on the formation of azobenzene-based ionic liquid micelles due to the pore size, thereby preventing the formation of larger micelles that could lead to a decrease in conductivity. Consequently, the ion conductivities of the azobenzene-based ionic liquids are higher in the nanochannels of the AAO templates. The effects of the length of carbon chains on the azobezene-based ionic liquids and the pore size of the AAO templates have also been investigated. Additionally, through irradiation with UV/vis light, [AzoCnMIM][Br] can undergo reversible isomerization, thereby reversibly changing the sizes of the micelles and subsequently altering the ion conductivities.
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Human skin is stably colonized by a distinct microbiota that functions together with epidermal cells to maintain a protective physical barrier. Staphylococcus, a prominent genus of the skin microbiota, participates in colonization resistance, tissue repair, and host immune regulation in strain specific manners. To unlock the potential of engineering skin microbial communities, we aim to fully characterize the functional diversity of this genus within the context of the skin environment. We conducted metagenome and pan-genome analyses of isolates obtained from distinct body sites of healthy volunteers, providing a detailed biogeographic depiction of staphylococcal species that colonize our skin. S. epidermidis, S. capitis, and S. hominis were the most abundant species present in all volunteers and were detected at all body sites. Pan-genome analysis of these three species revealed that the genus-core was dominated by central metabolism genes. Species-specific core genes were enriched in host colonization functions. The majority (~68%) of genes were detected only in a fraction of isolate genomes, underscoring the immense strain-specific gene diversity. Conspecific genomes grouped into phylogenetic clades, exhibiting body site preference. Each clade was enriched for distinct gene-sets that are potentially involved in site tropism. Finally, we conducted gene expression studies of select isolates showing variable growth phenotypes in skin-like medium. In vitro expression revealed extensive intra- and inter-species gene expression variation, substantially expanding the functional diversification within each species. Our study provides an important resource for future ecological and translational studies to examine the role of shared and strain-specific staphylococcal genes within the skin environment.
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Blockchain has become a well-known, secured, decentralized datastore in many domains, including medical, industrial, and especially the financial field. However, to meet the requirements of different fields, platforms that are built on blockchain technology must provide functions and characteristics with a wide variety of options. Although they may share similar technology at the fundamental level, the differences among them make data or transaction exchange challenging. Cross-chain transactions have become a commonly utilized function, while at the same time, some have pointed out its security loopholes. It is evident that a secure transaction scheme is desperately needed. However, what about those nodes that do not behave? It is clear that not only a secure transaction scheme is necessary, but also a system that can gradually eliminate malicious players is of dire need. At the same time, integrating different blockchain systems can be difficult due to their independent architectures, and cross-chain transactions can be at risk if malicious attackers try to control the nodes in the cross-chain system. In this paper, we propose a dynamic reputation management scheme based on the past transaction behaviors of nodes. These behaviors serve as the basis for evaluating a node's reputation to support the decision on malicious behavior and enable the system to intercept it in a timely manner. Furthermore, to establish a reputation index with high precision and flexibility, we integrate Particle Swarm Optimization (PSO) into our proposed scheme. This allows our system to meet the needs of a wide variety of blockchain platforms. Overall, the article highlights the importance of securing cross-chain transactions and proposes a method to prevent misbehavior by evaluating and managing node reputation.
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Cadena de Bloques , Confianza , Industrias , Nonoxinol , TecnologíaRESUMEN
Introduction: Primary dysmenorrhea (PDM) is a common condition among women of reproductive age, characterized by menstrual pain in the absence of any organic causes. Previous research has established a link between the A118G polymorphism in the mu-opioid receptor (OPRM1) gene and pain experience in PDM. Specifically, carriers of the G allele have been found to exhibit maladaptive functional connectivity between the descending pain modulatory system and the motor system in young women with PDM. This study aims to explore the potential relationship between the OPRM1 A118G polymorphism and changes in white matter in young women with PDM. Methods: The study enrolled 43 individuals with PDM, including 13 AA homozygotes and 30 G allele carriers. Diffusion tensor imaging (DTI) scans were performed during both the menstrual and peri-ovulatory phases, and tract-based spatial statistics (TBSS) and probabilistic tractography were used to explore variations in white matter microstructure related to the OPRM1 A118G polymorphism. The short-form McGill Pain Questionnaire (MPQ) was used to access participants' pain experience during the MEN phase. Results: Two-way ANOVA on TBSS analysis revealed a significant main effect of genotype, with no phase effect or phase-gene interaction detected. Planned contrast analysis showed that during the menstrual phase, G allele carriers had higher fractional anisotropy (FA) and lower radial diffusivity in the corpus callosum and the left corona radiata compared to AA homozygotes. Tractographic analysis indicated the involvement of the left internal capsule, left corticospinal tract, and bilateral medial motor cortex. Additionally, the mean FA of the corpus callosum and the corona radiata was negatively correlated with MPQ scales in AA homozygotes, but this correlation was not observed in G allele carriers. No significant genotype difference was found during the pain-free peri-ovulary phase. Discussion: OPRM1 A118G polymorphism may influence the connection between structural integrity and dysmenorrheic pain, where the G allele could impede the pain-regulating effects of the A allele. These novel findings shed light on the underlying mechanisms of both adaptive and maladaptive structural neuroplasticity in PDM, depending on the specific OPRM1 polymorphism.
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Over the past few decades, stimuli-responsive materials have been widely applied to porous surfaces. Permeability and conductivity control of ions confined in nanochannels modified with stimuli-responsive materials, however, have been less investigated. In this work, the permeability and conductivity control of ions confined in nanochannels of anodic aluminum oxide (AAO) templates modified with thermo-responsive poly(N-isopropylacrylamide) (PNIPAM) brushes are demonstrated. By surface-initiated atom transfer radical polymerization (SI-ATRP), PNIPAM brushes are successfully grafted onto the hexagonally packed cylindrical nanopores of AAO templates. The surface hydrophilicities of the membranes can be reversibly altered because of the lower critical solution temperature (LCST) behavior of the PNIPAM polymer brushes. From electrochemical impedance spectroscopy (EIS) analysis, the temperature-gating behaviors of the AAO-g-PNIPAM membranes exhibit larger impedance changes than those of the pure AAO membranes at higher temperatures because of the aggregation of the grafted PNIPAM chains. The reversible surface properties caused by the extended and collapsed states of the polymer chains are also demonstrated by dye release tests. The smart thermo-gated and ion-controlled nanoporous membranes are suitable for future smart membrane applications.
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Background: Soy sauce is widely used in a variety of Asian dishes to enhance flavor. Soybean and most soybean products, including soy sauces, are listed as prohibited foods in a low iodine diet. However, the iodine content in soy sauces is largely unknown. The aim of this study was to determine the iodine content in domestic soy sauces in Taiwan. Methods: Twenty-five different kinds of soy sauces were diluted with distilled water and with a dilution factor of fifty or above. Iodine concentrations of the diluted samples were measured colourimetrically based on the Sandell-Kolthoff reaction by a modified microplate method. All the measurements were repeated twelve times on three different days for determination of mean and standard deviation (SD), and coefficients of variance (CV). Serial dilution and recovery tests were also performed for validation. The results were confirmed by an inductively coupled plasma mass spectrometry (ICP-MS) method. Results: Among the twenty-five surveyed soy sauces, most of them (n=22) were iodine-free (<16 ug/L, and thus un-detectable). The iodine concentrations (mean ± SD) of the three iodine-containing soy sauces were 2.7 ± 0.1, 5.1 ± 0.2, and 10.8 ± 0.6 mg/L, respectively. The inter-assay, intra-assay and total CVs were all <5.3% for the modified microplate method. The results obtained by ICP-MS were consistent with those of the modified microplate method. The recovery rates in the serial dilution test and recovery test ranged from 94.7% to 118.6%. Two of the three iodine-containing soy sauces were supplemented with kelp extract, while the other one without kelp extract had the highest amount of salt among the three iodine-containing soy sauces. Therefore, we postulate that iodized salt instead of kelp extract is the source of higher iodine content in that sauce. Conclusion: The results suggest that most soy sauces are iodine-free and may be allowed during low iodine diets.
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Alimentos de Soja , Alimentos de Soja/análisis , TaiwánRESUMEN
BACKGROUND: Psoriasis is a complex, chronic, lifelong inflammatory skin disease characterized by the development of erythematous, indurated, scaly, pruritic, and often painful skin plaques, and it is currently incurable. It profoundly affects psychological wellbeing and social functioning and has significant associated co-morbidities. To improve clinical approaches, understanding of the experiences of patients with psoriasis is needed. OBJECTIVE: To explore the experiences and coping behaviors of patients with psoriasis. METHODS: A qualitative study approach was conducted. Through semi-structured interviews, 20 patients with psoriasis were recruited from general practices and specialist dermatology practices in a regional teaching hospital in Taiwan. Recorded interviews were transcribed and analyzed by content analysis. RESULTS: Three themes and nine subthemes were identified: (1) Symptoms distress: (a) trouble with scaling, (b) bothersome itching, and (c) complex pain experiences; (2) Psychological distress: (a) encountering discrimination and (b) feeling stigmatized; (3) Managing psoriasis: (a) coping with symptoms, (b) seeking alternative methods, (c) using biologic agents, and (d) changing thinking and coexisting with the disease. CONCLUSION: The experience of patients with psoriasis has significant negative impacts on their lives. The findings of this study can provide healthcare professionals with a reference for the care of patients with psoriasis.