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While irregular and geometrically complex pore networks are ubiquitous in nature and industrial processes, there is no universal model describing nanoparticle transport in these environments. 3D super-resolution nanoparticle tracking was employed to study the motion of passive (Brownian) and active (self-propelled) species within complex networks, and universally identified a mechanism involving successive cavity exploration and escape. In all cases, the long-time ensemble-averaged diffusion coefficient was proportional to a quantity involving the characteristic length scale and time scale associated with microscopic cavity exploration and escape (D â¼ r2/ttrap), where the proportionality coefficient reflected the apparent porous network connectivity. For passive nanoparticles, this coefficient was always lower than expected theoretically for a random walk, indicating reduced network accessibility. In contrast, the coefficient for active nanomotors, in the same pore spaces, aligned with the theoretical value, suggesting that active particles navigate "intelligently" in porous environments, consistent with kinetic Monte Carlo simulations in networks with variable pore sizes. These findings elucidate a model of successive cavity exploration and escape for nanoparticle transport in porous networks, where pore accessibility is a function of motive force, providing insights relevant to applications in filtration, controlled release, and beyond.
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[This corrects the article DOI: 10.3389/fendo.2024.1351281.].
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Background: Unexplained recurrent implantation failure and the high cost of assisted reproductive techniques for those experiencing infertility have increasingly resulted in the use of acupuncture. However, the trends and research status of acupuncture on infertility resulting in natural conception have not been systematically summarized. This scoping review and knowledge graph analysis aimed to summarize existing clinical studies on acupuncture for infertility that resulted in natural conception. Methods: Seven databases, namely, PubMed, Embase, the Cochrane Library, CNKI, VIP, Wanfang Data, and SinoMed, were searched up to August 2023 (updated on 1 April). Two authors independently identified related clinical studies and systematic reviews, and extracted data from included studies on acupuncture for infertility; any discrepancies were resolved by discussion or judged by a third author. A meta-analysis was conducted based on randomized controlled trials (RCTs), and data were synthesized using risk ratios with 95% confidence intervals. Results: Of the 310 articles meeting the inclusion criteria, 274 were primary studies, 7 were systematic reviews, and 29 were case reports. Reported adverse events included mild ovarian irritation and early signs of miscarriage. Out of the 274 primary studies, there were 40 (14.60%) cases of male infertility and 234 (85.40%) cases of female infertility. Current research highlights on acupuncture for infertility focused on female infertility caused by polycystic ovary syndrome, ovulation disorder, and luteinized unruptured follicle syndrome (LUFS), while acupuncture for male infertility was a hotspot in the early research stage. The meta-analysis also suggested that acupuncture was more effective than human chorionic gonadotropin (HCG) [RR = 1.89, 95% CI (1.47, 2.42), 11 RCTs, 662 participants]. Acupuncture combined with HCG was comparable to HCG [RR = 2.33, 95% CI (1.53, 3.55), four RCTs, 259 participants]. Compared with no treatment, acupuncture resulted in a higher pregnancy rate [RR = 22.12, 95% CI (1.39, 353.09), one RCT, 47 participants]. There was no statistical difference between acupuncture combined with HCG plus letrozole and HCG plus letrozole [RR = 1.56, 95% CI (0.84, 2.89), one RCT, 84 participants]. Conclusion: Current research highlights on acupuncture for infertility resulting in natural conception focused on female infertility caused by polycystic ovary syndrome, ovulation disorder, and LUFS, while studies on male infertility and female infertility caused by blockage in the fallopian tube, thin endometrium, and other factors were insufficient. Well-designed confirmatory clinical studies are still needed as the research hypotheses of most studies were unclear.
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Terapia por Acupuntura , Bibliometría , Infertilidad Femenina , Humanos , Terapia por Acupuntura/métodos , Terapia por Acupuntura/tendencias , Femenino , Infertilidad Femenina/terapia , Masculino , Infertilidad/terapia , Embarazo , Infertilidad Masculina/terapiaRESUMEN
OBJECTIVE: To observe the clinical effect of prophylaxis on migraine without aura differentiated as liver yang hyperactivity undergoing acupuncture at the points selected using the "seven lines of the neck" method. METHODS: Fifty-eight patients with migraine without aura of liver yang hyperactivity at remission stage were randomly divided into an observation group (29 cases, 3 cases dropped out) and a control group (29 cases, 4 cases dropped out). In the observation group, acupuncture was delivered at Dazhui (GV 14), Fengfu (GV 16), bilateral Fengchi (GB 20), Gongxue (Extra), etc., selected using the "seven lines of the neck" method. In the control group, conventional acupuncture was applied to ashi point, Sizhukong (TE 23), Shuaigu (GB 8), Taiyang (EX-HN 5) and others on the affected side. The treatment was given once every other day or every two days, 3 interventions weekly, for consecutive 8 weeks. Before treatment, after 4 and 8 weeks of treatment, and after 4 weeks of treatment completion (follow-up visit), the days of migraine episodes, the frequency of migraine episodes, the score of visual analogue scale (VAS) for pain intensity, and the score of migraine specific quality of life questionnaire (MSQ) were observed in the patients of the two groups. Before treatment and after 8 weeks of treatment, the score of TCM syndrome was observed. After 4 and 8 weeks of treatment and after 4 weeks of treatment completion (follow-up visit), the response rates of 50% reduction in the days and the frequency of migraine episodes were calculated in the two groups. RESULTS: After 4 and 8 weeks of treatment and during follow-up visit, the days and the frequency of migraine episodes were decreased (P<0.01) and VAS scores were declined (P<0.01) when compared with those before treatment in the two groups. The days and the frequency of migraine episodes in the observation group were lower during the follow-up visit (P<0.05) and VAS scores were lower after 8 weeks of treatment and during the follow-up visit (P<0.05) when compared with those in the control group. After 4 and 8 weeks of treatment, and during follow-up visit, the scores of "role function-preventive" and "emotional function" of MSQ were increased in comparison with those before treatment in the observation group (P<0.05). After 8 weeks of treatment and during the follow-up visit, the scores of "role function-restrictive" of MSQ were increased in comparison with those before treatment in the observation group (P<0.05), and the scores of "role function-restrictive" "role function-preventive" and "emotional function" were higher when compared with those before treatment in the control group (P<0.05). After 8 weeks of treatment, the scores of TCM syndrome were decreased in comparison with those before treatment in the two groups (P<0.01). In the observation group, the response rate of 50% reduction in the days of migraine episodes after 8 weeks of treatment and that of the frequency of migraine episodes during the follow-up visit were higher than those of the control group (P<0.05). CONCLUSION: Acupuncture at the points selected using the "seven lines of the neck" method can reduce the days and frequency of migraine episodes and pain intensity, ameliorate the syndrome of TCM and improve the quality of life of the patients with migraine without aura of liver yang hyperactivity.
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Puntos de Acupuntura , Terapia por Acupuntura , Migraña sin Aura , Humanos , Femenino , Masculino , Adulto , Persona de Mediana Edad , Migraña sin Aura/terapia , Migraña sin Aura/fisiopatología , Resultado del Tratamiento , Hígado/fisiopatología , Adulto Joven , Anciano , Calidad de VidaRESUMEN
OBJECTIVES: To observe the clinical efficacy of acupuncture intervention at different time for patients with sudden hearing loss. METHODS: According to the timing of acupuncture intervention, 86 patients were divided into early exposure group (n=43) and late exposure group (n=43) . The early exposure group was given acupuncture treatment within 14 days of onset, and the late exposure group was given acupuncture treatment after 14 days of onset. After propensity score matching (PSM, a statistical matching technique for observational data) processing by using SPSS26.0 software, outcomes of 30 cases in the early exposure group and 30 cases in the late exposure group were analyzed. In addition to receiving basic treatment with drugs for vascular dilatation, thrombolysis, nourishing nerve, etc., all patients of the two groups were treated with neck acupuncture ("Neck Seven Meridian Lines" acupuncture), once every other day except Sundays, for a total of 12 time. Before, after the treatment and 3 months after the treatment, the total score of the Tinnitus Handicap Inventory (THI, 0, 2 and 4 points for each of the 25 items, total scores = 100 points) scale was used to evaluate the improvement of tinnitus symptoms caused by hearing loss. The clinical therapeutic effect was evaluated according to the efficacy grading criteria in the Guidelines for Diagnosis and Treatment of Sudden Deafness (2015) and the changes of pure tone audiometry curve. Multivariate Logistic regression was used to analyze the effect of factors that might influence efficacy before propensity score matching. RESULTS: The THI scores of patients in both groups decreased strikingly after the treatment and 3 months' follow-up (P<0.05). Compared with the same time-points of the late exposure group, the total THI scores of post-treatment and 3 months' follow-up were evidently lower in the early exposure group (P<0.05). The effective rate of the early exposure group (22/30, 80.00%) was significantly higher (P<0.05) than that of the late exposure group (16/30, 53.33%). The classification of sudden deafness and the application of traditional Chinese medicine in this study were not independent factors affecting the total effective rate. CONCLUSIONS: The time point of acupuncture intervention is an important factor affecting the effect on hearing and tinnitus disability of patients with sudden deafness. The earlier acupuncture treatment is accepted, the better the therapeutic effect is.
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Terapia por Acupuntura , Pérdida Auditiva Súbita , Humanos , Pérdida Auditiva Súbita/terapia , Masculino , Femenino , Persona de Mediana Edad , Adulto , Resultado del Tratamiento , Anciano , Factores de Tiempo , Puntos de Acupuntura , Adulto Joven , Acúfeno/terapiaRESUMEN
Artificial micro/nanomotors are expected to perform tasks in interface-rich and species-rich environments for biomedical and environmental applications. In these highly confined and interconnected pore spaces, active species may influence the motion of coexisting passive participants in unexpected ways. Using three-dimensional super-resolution single-nanoparticle tracking, we observed enhanced motion of passive nanoparticles due to the presence of dilute well-separated nanomotors in an interconnected pore space. This enhancement acted at distances that are large compared to the sizes of the particles and cavities, in contrast with the insignificant effect on the passive particles with the same dilute concentration of nanomotors in an unconfined liquid. Experiments and simulations suggested an amplification of hydrodynamic coupling between self-propelled and passive nanoparticles in the interconnected confined environment, which enhanced the effective energy for passive particles to escape cavities through small holes. This finding represents an emergent behavior of confined nanomotors and suggests new strategies for the development of antifouling membranes and drug delivery systems.
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Control over the surface chemistry of elastomers such as polydimethylsiloxane (PDMS) is important for many applications. However, achieving nanostructured chemical control on amorphous material interfaces below the length scale of substrate heterogeneity is not straightforward, and can be particularly difficult to decouple from changes in network structure that are required for certain applications (e.g., variation of elastic modulus for cell culture). We have recently reported a new method for precisely structured surface functionalization of PDMS and other soft materials, which displays high densities of ligands directly on the material surface, maximizing steric accessibility. Here, we systematically examine structural factors in the PDMS components (e.g., base and cross-linker structures) that impact efficiency of the interfacial reaction that leads to surface functionalization. Applying this understanding, we demonstrate routes for generating equivalent nanometer-scale functional patterns on PDMS with elastic moduli from 0.013 to 1.4 MPa, establishing a foundation for use in applications such as cell culture.
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Multivalent interactions between carbohydrates and proteins enable a broad range of selective chemical processes of critical biological importance. Such interactions can extend from the macromolecular scale (1-10 nm) up to much larger scales across a cell or tissue, placing substantial demands on chemically patterned materials aiming to leverage similar interactions in vitro. Here, we show that diyne amphiphiles with carbohydrate headgroups can be assembled on highly oriented pyrolytic graphite (HOPG) to generate nanometer-resolution carbohydrate patterns, with individual linear carbohydrate assemblies up to nearly 1 µm, and microscale geometric patterns. These are then photopolymerized and covalently transferred to the surfaces of hydrogels. This strategy suspends carbohydrate patterns on a relatively rigid polydiacetylene (persistence length â¼ 16 nm), exposed at the top surface of the hydrogel above the bulk pore structure. Transferred patterns of appropriate carbohydrates (e.g., N-acetyl-d-glucosamine, GlcNAc) enable selective, multivalent interactions (KD â¼ 40 nM) with wheat germ agglutinin (WGA), a model lectin that exhibits multivalent binding with appropriately spaced GlcNAc moieties. WGA binding affinity can be further improved (KD â¼ 10 nM) using diacetylenes that shift the polymer backbone closer to the displayed carbohydrate, suggesting that this strategy can be used to modulate carbohydrate presentation at interfaces. Conversely, GlcNAc-patterned surfaces do not induce specific binding of concanavalin A, and surfaces patterned with glucuronic acid, or with simple carboxylic acid or hydroxyl groups, do not induce WGA binding. More broadly, this approach may have utility in designing synthetic glycan-mimetic interfaces with features from molecular to mesoscopic scales, including soft scaffolds for cells.
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Hidrogeles , Lectinas , Lectinas/metabolismo , Carbohidratos/química , Aglutininas del Germen de Trigo/química , Concanavalina ARESUMEN
Many areas of modern materials chemistry, from nanoscale electronics to regenerative medicine, require design of precisely-controlled chemical environments at near-molecular scales. Most work on high-resolution interface patterning to date has focused on hard surfaces, such as those for electronics. However, design of interfaces for biological environments increasingly requires precise control over interfaces of soft materials, which is in many cases complicated by nano-to-microscale heterogeneity in the substrate material. In this Feature Article, we describe historical approaches to nanoscale patterning on hard surfaces, challenges in extension to soft interfaces, and an approach to molecular-scale hard and soft interface design based on self-assembled molecular networks, which can be assembled noncovalently on hard surfaces to generate nanometer-scale patterns, then covalently transferred to soft materials including PDMS and hydrogels.
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Electrónica , HidrogelesRESUMEN
Hydrogels are broadly used in applications where polymer materials must interface with biology. The hydrogel network is amorphous, with substantial heterogeneity on length scales up to hundreds of nanometers, in some cases raising challenges for applications that would benefit from highly structured interactions with biomolecules. Here, we show that it is possible to generate ordered patterns of functional groups on polyacrylamide hydrogel surfaces. We demonstrate that, when linear patterns of amines are transferred to polyacrylamide, they pattern interactions with DNA at the interface, a capability of potential importance for preconcentration in chromatographic applications, as well as for the development of nanostructured hybrid materials and supports for cell culture.
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Hidrogeles , Polímeros , Resinas Acrílicas , Aminas , ADN/química , Hidrogeles/químicaRESUMEN
Most high-resolution interfacial patterning approaches are restricted to crystalline inorganic interfaces. Recently, we have shown that it is possible to generate 1 nm resolution functional patterns on soft materials, such as polydimethylsiloxane (PDMS), by creating highly structured striped patterns of functional alkyldiacetylenes on a hard crystalline surface, photopolymerizing to set the molecular pattern as a striped-phase polydiacetylene (sPDA), and then covalently transferring the sPDAs to PDMS. Transfer depends on the diacetylene polymerization, making it important to understand design principles for efficient sPDA polymerization and cross-linking to PDMS. Here, we combine single-molecule and fluorescence-based metrics for sPDA polymerization and transfer, first to characterize sPDA polymerization of amine striped phases, and then to develop a probabilistic model that describes the transfer process in terms of sPDA-PDMS cross-linking reaction efficiency and number of reactions required for transfer. We illustrate that transferred patterns of alkylamines can be used to direct both adsorption of CdSe nanocrystals with alkyl ligand shells and covalent reactions with fluorescent dyes, highlighting the utility of functional patterning of the PDMS surface.
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The evolution of lipids in nanoscience exemplifies the powerful coupling of advances in science and technology. Here, we describe two waves of discovery and innovation in lipid materials: one historical and one still building. The first wave leveraged the relatively simple capability for lipids to orient at interfaces, building layers of functional groups. This simple form of building with atoms yielded a stunning range of technologies: lubricant additives that dramatically extended machine lifetimes, molecules that enabled selective ore extraction in mining, and soaps that improved human health. It also set the stage for many areas of modern nanoscience. The second wave of lipid materials, still growing, uses the more complex toolkits lipids offer for building with atoms, including controlling atomic environment to control function (e.g., pKa tuning) and the generation of more arbitrary two-dimensional and three-dimensional structures, including lipid nanoparticles for COVID-19 mRNA vaccines.
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COVID-19 , Nanopartículas , Humanos , Lípidos , ARN Mensajero , SARS-CoV-2RESUMEN
Lamellar phases of alkyldiacetylenes in which the alkyl chains lie parallel to the substrate represent a straightforward means for scalable 1-nm-resolution interfacial patterning. This capability has the potential for substantial impacts in nanoscale electronics, energy conversion, and biomaterials design. Polymerization is required to set the 1-nm functional patterns embedded in the monolayer, making it important to understand structure-function relationships for these on-surface reactions. Polymerization can be observed for certain monomers at the single-polymer scale using scanning probe microscopy. However, substantial restrictions on the systems that can be effectively characterized have limited utility. Here, using a new multi-scale approach, we identify a large, previously unreported difference in polymerization efficiency between the two most widely used commercial diynoic acids. We further identify a core design principle for maximizing polymerization efficiency in these on-surface reactions, generating a new monomer that also exhibits enhanced polymerization efficiency.
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Nanocrystals are often synthesized using technical grade reagents such as oleylamine (OLAm), which contains a blend of 9-cis-octadeceneamine with trans-unsaturated and saturated amines. Here, we show that gold nanowires (AuNWs) synthesized with OLAm ligands undergo thermal transitions in interfacial assembly (ribbon vs. nematic); transition temperatures vary widely with the batch of OLAm used for synthesis. Mass spectra reveal that higher-temperature AuNW assembly transitions are correlated with an increased abundance of trans and saturated chains in certain blends. DSC thermograms show that both pure (synthesized) and technical-grade OLAm have primary melting transitions near -5 °C (20-30 °C lower than the literature melting temperature range of OLAm). A second, broader melting transition (in the previous reported melting range) appears in technical grade blends; its temperature varies with the abundance of trans and saturated chains. Our findings illustrate that, similar to biological membranes, blends of alkyl chains can be used to generate mesoscopic hierarchical nanocrystal assembly, particularly at interfaces that further modulate transition temperatures.
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Nanocables , Aminas , Oro , TemperaturaRESUMEN
Decades of work in surface science have established the ability to functionalize clean inorganic surfaces with sub-nm precision, but for many applications, it would be useful to provide similar control over the surface chemistry of amorphous materials such as elastomers. Here, we show that striped monolayers of diyne amphiphiles, assembled on graphite and photopolymerized, can be covalently transferred to polydimethylsiloxane (PDMS), an elastomer common in applications including microfluidics, soft robotics, wearable electronics, and cell culture. This process creates precision polymer films <1 nm thick, with 1 nm wide functional patterns, which control interfacial wetting and reactivity, and template adsorption of flexible, ultranarrow Au nanowires. The polydiacetylenes exhibit polarized fluorescence emission, revealing polymer location, orientation, and environment, and resist engulfment, a common problem in PDMS functionalization. These findings illustrate a route for patterning surface chemistry below the length scale of heterogeneity in an amorphous material.
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As two-dimensional (2D) materials are more broadly utilized as components of hybrid materials, controlling their surface chemistry over large areas through noncovalent functionalization becomes increasingly important. Here, we demonstrate a thermally controlled rotary transfer stage that allows areas of a 2D material to be continuously cycled into contact with a Langmuir film. This approach enables functionalization of large areas of the 2D material and simultaneously improves long-range ordering, achieving ordered domain areas up to nearly 10â¯000 µm2. To highlight the layer-by-layer processing capability of the rotary transfer stage, large-area noncovalently adsorbed monolayer films from an initial rotary cycle were used as templates to assemble ultranarrow gold nanowires from solution. The process we demonstrate would be readily extensible to roll-to-roll processing, addressing a longstanding challenge in scaling Langmuir-Schaefer transfer for practical applications.
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A series of tris(pyrazolyl)borate mono-, di- and trinuclear complexes, [Tp2Ln]nX (Ln = Eu, Tb, Gd, Dy, Xn- = various mono-, bis- and tris(ß-diketonates) has been prepared. The Tb3+ and Dy3+ complexes are luminescent single molecular magnets (SMM) and exhibit luminescence quantum efficiencies up to 73% for the Tb3+ and 4.4% for the Dy3+ compounds. Similar Eu3+ complexes display bright emission only at lower temperatures. The Dy3+ and Tb3+ complexes possess SMM behavior in a non-zero dc field at low temperatures, while the polynuclear Dy3+ complexes also show slow magnetic relaxation even in zero dc field up to 8 K. Ueff-values determined from dynamic magnetic measurements were up to 31 and 6 cm-1 for the Dy3+ and Tb3+ complexes, respectively. It was found that within a series of Dy3+ and Tb3+ compounds, Ueff and luminescence quantum yields decreased with increasing nuclearity of the compounds and a shortening of the intramolecular Ln-Ln distance. ΔOrbach-values estimated from low-temperature luminescence spectra were significantly higher than those obtained from ac magnetic data, which may be due to involvement of additional processes in the relaxation mechanism (quantum tunneling, Raman, direct) reducing the energy barrier. Some of the Tb3+-compounds also display metal-centred electroluminescence, giving them potential as emitting layers in LEDs.