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Properly cleansing the skin surface plays a crucial role in maintaining the overall body health. Incorporating nanoparticles into skincare products can enhance deep cleansing applications of the skin within the complex system formed by epidermal secretions. This study presents a nanoparticle cleansing tool, namely, patchy structure lignin composite nanoparticles. Lignin, a natural polymer, exhibits the ability to self-assemble into ultrasmall nanosized particles when exposed to a suitable solvent. Meanwhile, the surface of traditional SiO2 clean powder can be modified using rapid grafting techniques to create patchy structures. When these nanoparticles, featuring a patchy microconvex structure, come into contact with the skin, they exhibit stronger friction performance compared to hydrated silica with a smooth surface. As a result, an interlocking state forms among the nanoparticles, facilitating the removal of complex skin systems through the formation of a nanoparticle chain network. This ultimately leaves the skin cleaner and fresher. The unique composition and structure of these patchy composite nanoparticles provide an innovative approach to the development of cleansing products. [ABSTRACT FROM AUTHOR]

Juvenile onset systemic lupus erythematosus (JSLE) is a rare multisystem, autoimmune disorder. Alopecia in SLE generally follows a pre-established disease with systemic symptoms. A 13-year-old girl presented with sudden hair loss over the vertex of scalp of 1-month duration. No other cutaneous or systemic symptoms were noted. Trichoscopy, histopathology, positive ANA, and low complement levels helped in diagnosing JSLE. Patchy nonscarring alopecia, as the sole presenting feature without systemic involvement, is rare.

Topical corticosteroids (TC) and/or intralesional corticosteroids (IC) are considered first-line treatments for patch-type alopecia areata (AA). However, the efficacies of TC monotherapy, IC monotherapy, and combined topical and intralesional corticosteroids (CC) in patients with AA have never been compared. To evaluate and compare the efficacy and tolerability of 3 corticosteroid treatments (TC, IC, and CC) in patients with AA. A study of patients with AA who received TC, IC, or CC was conducted. Outcomes including initial hair regrowth (25% regrowth), significant hair regrowth (>80% regrowth), and adverse events were statistically compared. Cox proportional hazards regression analysis was used to identify factors that influence the treatment response. One hundred and forty-eight patients were eligible for analysis. The response rates of initial and significant hair regrowth were comparable among 3 treatment groups. Multivariate analysis revealed that an AA treatment duration of longer than 6 months was associated with a lower probability of significant hair regrowth. A small proportion of patients experienced adverse effects. The 3 corticosteroid treatment regimens are effective, safe, and show no significant differences in treatment outcomes. However, an AA duration longer than 6 months portends a lack of significant hair regrowth. [ABSTRACT FROM AUTHOR]

Juvenile onset systemic lupus erythematosus (JSLE) is a rare multisystem, autoimmune disorder. Alopecia in SLE generally follows a pre-established disease with systemic symptoms. A 13-year-old girl presented with sudden hair loss over the vertex of scalp of 1-month duration. No other cutaneous or systemic symptoms were noted. Trichoscopy, histopathology, positive ANA, and low complement levels helped in diagnosing JSLE. Patchy nonscarring alopecia, as the sole presenting feature without systemic involvement, is rare. [ABSTRACT FROM AUTHOR]

We report the formation of colloidal polymers consisting of disk-like silica nanoparticles (NPs) with polystyrene (PS) chains at the bottom of their two cavities assembled through reduction of the solvent quality for the PS chains and linked by hydrophobic associations. We show that this NPs assembly exhibits a two-stage process involving reaction-controlled polymerization and diffusion-controlled polymerization. Colloidal polymer networks are produced by the incorporation of three-patch NPs, which serve as branching points between the colloidal chains. By co-assembling preformed homopolymers composed of patchy NPs of different sizes or surface chemical groups, block copolymers are also achieved. This study provides insight into the process of self-assembly of two-patch NPs by precisely designing the components to generate colloidal analogues of linear macromolecular chains. [ABSTRACT FROM AUTHOR]

Lignin, a natural polyphenol polymer, is a biocompatible, cost-effective and accessible material. To fully utilize the benefits of lignin, it is crucial to transform its complex macromolecules into nanoscale particles in a single solvent. In this research, an assembly-mediated internal cross-linking method in single solvent was proposed to manufacture cross-linked lignin colloidal particles with nanoscale particle size controlled to be around 50 nm. Then, cross-linked lignin composite particles with a unique "patchy" structure for dental cleansing were obtained by rapidly grafting the cross-linked lignin colloidal particles onto the surface of silica microspheres through the bridging effect of silane coupling agent. The resulting composite particles have rivets with adjustable hardness, significantly lower than traditional abrasives like silica in both hardness and modulus. Through the group cleansing behavior of soft interlocking, a breakthrough has been achieved in the high solid content agglomeration friction mode of traditional abrasives, which effectively reduces tooth wear and exhibits an excellent plaque removal effect. [Display omitted] [ABSTRACT FROM AUTHOR]

Amphiphilic block copolymers are able to assemble into spherical micelles in an aqueous solution. Spherical micelles are expected to adsorb on the surface of colloidal nanoparticles (NPs) through hydrogen-bonding interaction. Hence, it should be possible to guide the area-selective deposition of precursors onto the exposed surface of colloidal seeds, where no micelles are adsorbed. Using colloidal silica and polydopamine nanospheres as seeds, block copolymer F127 and P123 are used as surface modifiers to guide the controlled solution-phase deposition of precursors on a selectively exposed surface of seed NPs, leading to the formation of patchy NPs. Effects of the addition amount of tetraethoxysilane (TEOS), types of block copolymers, and the volume fraction of miscible organic solvents on the size and morphology of patchy silica NPs are investigated systematically through electron microscopic imaging. Block copolymer micelles adsorption model for the formation of colloidal patchy NPs is first proposed. Our study suggests that the shape and size of patchy silica NPs are determined by the amount of TEOS and dielectric constant of solution. [ABSTRACT FROM AUTHOR]

In the present study we are performing simulation of simple model of two patch colloidal particles undergoing irreversible diffusion limited cluster aggregation using patchy Brownian cluster dynamics. In addition to the irreversible aggregation of patches, the spheres are coupled with isotropic reversible aggregation through the Kern–Frenkel potential. Due to the presence of anisotropic and isotropic potential we have also defined three different kinds of clusters formed due to anisotropic potential and isotropic potential only as well as both the potentials together. We have investigated the effect of patch size on self-assembly under different solvent qualities for various volume fractions. We will show that at low volume fractions during aggregation process, we end up in a chain conformation for smaller patch size while in a globular conformation for bigger patch size. We also observed a chain to bundle transformation depending on the attractive interaction strength between the chains or in other words depending on the quality of the solvent. We will also show that bundling process is very similar to nucleation and growth phenomena observed in colloidal system with short range attraction. We have also studied the bond angle distribution for this system, where for small patches only two angles are more probable indicating chain formation, while for bundling at very low volume fraction a tail is developed in the distribution. While for the case of higher patch angle this distribution is broad compared to the case of low patch angles showing we have a more globular conformation. We are also proposing a model for the formation of bundles which are similar to amyloid fibers using two patch colloidal particles. [ABSTRACT FROM AUTHOR]

The role of stomatal heterogeneity in the response of stomatal conductance ( g s) to the mole fraction difference in water vapour between the inside of the leaf and the ambient air (Δ w) was determined using thermography and gas exchange for 3 species. The value of Δ w for the leaf was varied in 2 different ways: first by varying air humidity while holding leaf temperature constant and second by varying leaf temperature while holding air humidity constant. Stomatal heterogeneity was explored by examining the response of g s in small areas of the leaf (as determined by thermography) and comparing them to each other and to the average value of g s (as determined by gas exchange). These analyses show that despite substantial heterogeneity in g s values, the response of g s to Δ w was qualitatively similar in all areas of the leaf, and all responses of g s to Δ w were well predicted by a recently proposed, vapour-phase mechanism for stomatal responses to temperature and humidity. Remarkably, the 2 model parameters, Θ and Z, that depend on leaf anatomy were constant for a given species, and only the maximum conductance varied in different regions of the leaf. [ABSTRACT FROM AUTHOR]

Advances in colloidal synthesis allow for the design of particles with controlled patches. This article reviews routes towards colloidal locomotion, where energy is consumed and converted into motion, and its implementation with active patchy particles. A special emphasis is given to phoretic swimmers, where the self-propulsion originates from an interfacial phenomenon, raising experimental challenges and opening up opportunities for particles with controlled anisotropic surface chemistry and novel behaviors. [ABSTRACT FROM AUTHOR]

Inflamed organs display marked spatial heterogeneity of inflammation, with patches of inflamed tissue adjacent to healthy tissue. To investigate how nanocarriers (NCs) distribute between such patches, we created a mouse model that recapitulates the spatial heterogeneity of the inflammatory lung disease ARDS. NCs targeting the epitope PECAM strongly accumulated in the lungs, but were shunted away from inflamed lung regions due to hypoxic vasoconstriction (HVC). In contrast, ICAM-targeted NCs, which had lower whole-lung uptake than PECAM/NCs in inflamed lungs, displayed markedly higher NC levels in inflamed regions than PECAM/NCs, due to increased regional ICAM. Regional HVC, epitope expression, and capillary leak were sufficient to predict intra-organ of distribution of NCs, antibodies, and drugs. Importantly, these effects were not observable with traditional spatially-uniform models of ARDS, nor when examining only whole-organ uptake. This study underscores how examining NCs' intra-organ distribution in spatially heterogeneous animal models can guide rational NC design. [ABSTRACT FROM AUTHOR]

This article presents a study on the formation of anisometric, ellipsoidal supraparticles by evaporation-induced self-assembly from multicomponent colloidal dispersion droplets deposited on a superhydrophobic surface. Performing the formation process on bent surface substrates grants precise control on the shape and spatial orientation of the final dried supraparticles. Due to the V-shaped surfaces providing interfacial blockage, anisotropic evaporation rates occur with respect to the direction of the bending channel. This proportionally leads to inhomogeneous accumulation of fumed silica (FS), used as structure guiding component. Thus, upon the increase of FS-particle interaction via ionic strength (NaCl), this so-formed shell provides enough anisotropic stiffness resulting in predictable droplet deformation with the elongation orientation being perpendicular to the bending axis. The anisotropic evaporation rates were monitored and quantified using an established, empiric kinetic model and taking into account surface geometry. Employing this reliable control of elongation direction and using additional Fe3O4@SiO2 core-shell nanoparticles, anisometric magnetic Janus supraparticles with defined patch position were prepared, which are not accessible on flat surfaces. The results can find application in the controlled, easy to scale up, nanofabrication process of patchy anisometric supraparticles. [ABSTRACT FROM AUTHOR]

In this paper an epidemic model is proposed to describe the dynamics of disease spread among patches due to population migration. We formulate a Susceptible-Infective-Susceptible type of epidemiological disease transmission model in a habitat of two identical patches linked by migration and we study the effect of the self and cross diffusion on the stability of the endemic equilibrium with disease induced mortality and nonlinear incidence rate. We show that at a critical value of the bifurcation parameter the system undergoes a Turing bifurcation giving rise to non-constant stationary solutions. Numerical examples are also included. [ABSTRACT FROM AUTHOR]

[Display omitted] • Capillary-based microfluidic manipulation of PLGA microcarriers. • Collagen patchy structure on microcarriers for MSCs delivery. • Regulation of MSCs expansion/osteogenic differentiation via collagen content. This study was aimed to develop a capillary-based microfluidic methodology for preparing poly (lactic-co-glycolic acid) (PLGA) microcarriers patterned with collagen patchy structure (PLGA-Col), which are superior in enhancing proliferation and osteogenic differentiation of mesenchymal stem cells (MSCs) seeded on them. Primary W/O emulsions were first prepared using aqueous collagen and PLGA solutions. A two-phase microfluidic device was then designed and the emulsions were used as the inner liquid phase to obtain PLGA-Col microcarriers. The content of collagen was varied to yield PLGA-Col-L (lower collagen content) and PLGA-Col-H (higher collagen content). The proliferation behavior of the cells on the microcarriers was evaluated by live/dead cell staining and CCK-8 assays, while the osteogenic differentiation behavior was evaluated by ALP and qRT-PCR assays. Pristine PLGA microcarriers were also prepared to serve as a control. Three groups, PLGA, PLGA-Col-L, and PLGA-Col-H were then obtained. PLGA-Col was asymmetric with a rough/porous collagen patchy structure. All of these microcarriers could maintain morphology integrity for at least 3 weeks in the aqueous medium before undergoing obvious swelling (5w) and further erosion (7w). It was demonstrated that PLGA-Col could not only enhance the MSCs adhesion/proliferation but also mediate their subsequent osteogenic differentiation. PLGA-Col-L was suitable for supporting the MSCs proliferation, while PLGA-Col-H was more efficient in promoting the osteogenic differentiation of MSCs. Hence, the incorporation of collagen as a patchy structure into PLGA microspheres through the current microfluidic method could be an effective strategy to provide a superior type of microcarriers with well-defined functionality. [ABSTRACT FROM AUTHOR]

Fluorescence and thermal imaging were used to examine the dynamics of stomatal patches for a single surface ofXanthium strumariumL. leaves following a decrease in ambient humidity. Patches were not observed in all experiments, and in many experiments the patches were short-lived. In some experiments, however, patches persisted for many hours and showed complex temporal and spatial patterns. Rapidly sampled fluorescence images showed that the measurable variations of these patches were sufficiently slow to be captured by fluorescence images taken at 3-min intervals using a saturating flash of light. Stomatal patchiness with saturating flashes of light was not demonstrably different from that without saturating flashes of light, suggesting that the regular flashes of light did not directly cause the phenomenon. Comparison of simultaneous fluorescence and thermal images showed that the fluorescence patterns were largely the result of stomatal conductance patterns, and both thermal and fluorescence images showed patches of stomatal conductance that propagated coherently across the leaf surface. These nondispersing patches often crossed a given region of the leaf repeatedly at regular intervals, resulting in oscillations in stomatal conductance for that region. The existence of these coherently propagating structures has implications for the mechanisms that cause patchy stomatal behaviour as well as for the physiological ramifications of this phenomenon. [ABSTRACT FROM AUTHOR]

ABSTRACTInteractions among stomata within a single areole have recently been reported, and evidence suggests that hydraulic mechanisms may be responsible for these interactions. Such interactions may play a role in patchy stomatal behaviour by coordinating stomatal behaviour within areoles. However, models suggest that longer-distance interactions may be required to produce the large-scale discoordination that is characteristic of stomatal patchiness. This study was undertaken to characterize long-distance interactions between ‘artificial patches’ of stomata under varying conditions of evaporative demand and soil water stress. Gas-exchange was monitored in two adjacent regions (‘patches’) of a wheat leaf by two independent gas mixing and analysis systems. When photon flux density (PFD) was changed in only one of these patches, stomatal conductance responded in both patches in a manner consistent with hydraulic interactions propagated by changes in xylem water potential. These data are discussed in the context of mechanisms for patchy stomatal conductance and implications for the design and analysis of gas-exchange experiments. [ABSTRACT FROM AUTHOR]

Patchy alopecias of the scalp are frequently seen in clinical practice. We report a young man who presented with progressive patchy alopecia of the scalp, which was finally diagnosed to be due to tuberculoid leprosy. Progression of alopecia was stopped after anti-leprosy treatment was instituted. Despite high prevalence of leprosy in our country, scalp affection due to leprosy is extremely rare but important to recognize. [ABSTRACT FROM AUTHOR]

The existence of patchy stomatal closure suggests interactions among neighbouring stomata that synchronize stomatal movements in small areas of a leaf. To test for such interactions, water vapour partial pressure (ewv) for a small group of stomata was controlled independently of that for the surrounding stomata using gas flow from a small needle. The ewvfor the surrounding stomata was controlled with a larger gas flow, termed the primary flow. The spatial pattern of ewv isobars caused by the needle flow was assessed experimentally and theoretically. Stomatal apertures were monitored following perturbations in e[subwv], of the primary flow and the needle flow. Whenewv of the primary flow was perturbed and that of the needle flow held constant, stomata for which there was little or no perturbation in e[subwv] responded similarly to stomata experiencing the perturbation. When the ewv, of the needle flow was perturbed and that of the primary flow held constant, many stomata experiencing little or no perturbation responded similarly to those experiencing a large perturbation. The results are discussed in relation to a mechanism for stomatal interactions that has been proposed in a previous study. [ABSTRACT FROM AUTHOR]

Stomata of leaves can exhibit either temporally stable, spatially homogeneous behaviour or complex spatial and temporal dynamics, depending on environmental and physiological conditions. To test the ability of accepted physiological mechanisms to describe these patterns, we developed a simple, spatially explicit model of stomatal responses to humidity that incorporated hydraulic interactions among stomata. Model results showed qualitative agreement with experimental evidence for a number of phenomena: (1) at high humidities, whole-leaf steady-state conductance is a monotonic function of humidity; (2) the initial stomatal response following a perturbation in humidity is in the direction opposite to the final response, and (3) spatial dynamics include patch formation and self-organization similar to that observed in actual leaves. These comparisons do not eliminate other explanations, but do suggest that novel mechanisms need not be invoked to explain the diversity of spatial and temporal patterns of stomatal behaviour in leaves. [ABSTRACT FROM AUTHOR]

The qualitative influence of patchy stomatal conductance distributions on the values of photosynthesis (A) and intercellular CO2 concentration (ci) as determined by gas-exchange measurements were investigated using computer modelling. Gas-exchange measurements were simulated for different conductance distributions by modelling photosynthesis explicitly for each patch, summing these rates,and inferring ci from a diffusion equation. Qualitative relationships are presented between conductance distribution features and the difference between assimilation rates measured for patchy and homogeneous leaves at the same ci (Ap and Ah, respectively). These data show that, although most conductance distributions have little effect on the value of A measured for a given ci, some distribution features (which we have termed 'bimodality', 'position', 'skewness' and 'range') play a key role in controlling the magnitude of these effects. Distributions that are more nearly bimodal, span regions of lower conductance, are right-skewed, or have broader conductance ranges are associated with larger effects on the A(ci) relationship. To clarify our mathematical analysis and illustrate some of the trends it predicts, we present conductance distributions and gas-exchange data from leaves of Malus dolgo var. Spring Snow that were treated with ABA. The results are discussed in the light of recent controversy over the effect of patchy stomatal conductance on gas-exchange data. [ABSTRACT FROM AUTHOR]

In nature surfaces are rarely uniform, so terms such as `surface', `stomatal' or `canopy' resistance usually indicate some kind of average over a population of sub-areas, each with its own separate resistance. Questions then arise as to how gross measurements of these resistances should be interpreted in terms of the components, or how components should be aggregated into representative single values. Aggregation schemes have been published by Raupach (1991, Vegetation, 105-120) and Lhomme (1992, Agriculture and Forest Meteorology 61, 11-21), but these are different for reasons that were not explained. This paper develops the idea that averaging schemes should be designed to serve particular purposes, and that they can be varied to suit these purposes. It is shown that the `effective' resistances defined by Raupach and Lhomme preserve different quantities. A further averaging scheme is developed which preserves both correct transpiration rate and CO2 flux when used in the Penman-Monteith equation and an equation describing assimilation. All of these schemes are fairly complex, so the work provides a warning against naive use of effective variables. [ABSTRACT FROM AUTHOR]

Patchy stomatal movements were induced in leaves of Helianthus annuus L. and Xanthium strumarium L. by increasing Δw and decreasing light in a gas-exchange cuvette. The dynamics of the patchy movements were recorded and analysed using images of chlorophyll fluorescence, and the influence of heterogeneous stomatal activity on gas-exchange measurements of whole-leaf stomatal conductance was explored. Image series and gas- exchange measurements from two contrasting 100 mm experiments are presented. One series of images, taken using Helianthus annuus, was characterized by strongly oscillating stomatal conductance induced by a decrease in light at high Δw. Fluorescence analysis revealed that indi- vidual patches of the leaf displayed a variety of behaviours (from static to strongly oscillating fluorescence), which, when averaged, matched the time dependence of the oscillating stomatal conductance measured by gas-exchange techniques. During the second series of images, taken using Xanthium strumarium, stomatal conductance (measured with gas exchange) declined slightly after an increase in &Delta:w, and then maintained a steady state. Again, some patches in this leaf showed highly dynamic qNP although on the whole qNP varied without any obvious pattern or frequency. When all patch activity in this series was averaged, it paralleled the steady whole-leaf stomatal Conductance determined by gas-exchange measurements. It is clear from this work that coordinated patchy stomatal movements can contribute significantly to the dynamics of whole-leaf stomatal conductance, and, in contrast, that dynamic but uncoordinated patchy movements can average to produce a steady gas-exchange trace. [ABSTRACT FROM AUTHOR]

Images of chlorophyll fluorescence were used to demonstrate patchy stomatal closure at low humidities in leaves of well-watered Xanthium strumarium plants. The pattern and extent of patchy stomatal closure were shown to be different for the two surfaces of amphistomatous leaves by taking images of leaves with CO2 available to only one leaf surface at a time. When only one surface of the leaf was exposed to low humidity, patchiness was more extensive on that surface. Gas-exchange experiments were also conducted to determine the apparent photosynthetic capacity of the mesophyll (photosynthesis rate at constant cI) when it was supplied with CO2 through both surfaces or through each surface alone. These experiments showed declines in the apparent photosynthetic capacity of the mesophyll at low humidities that were consistent with patchy stomatal closure on one or both surfaces. The results suggest that patchy stomatal closure can be a factor in the steady-state reponses of stomata to humidity. In amphistomatous leaves this is further complicated by the fact that patches on one epidermis may not coincide with those of the other surface. [ABSTRACT FROM AUTHOR]

The influence of environmental heterogeneity on components of male and female fitness is examined using Atriplex canescens growing on steep slopes and alluvium at the slope base as a model system. Female fitness is estimated as the grams of fruit produced per plant and the grams of fruit per gram leaf tissue. Male fitness is estimated as the grams of stamens produced, the number of pollen grains dispersed to a given distance, and the potential number of grams of fruit sired taking into consideration the number and distribution of mates and competing pollen donors. The influence of increased plant size on male and female fitness components, the cost of reproduction (as measured by biomass, joules and nitrogen) on a gross level and a per offspring basis are also examined. The results indicate that the female function is more limited on the slope than the male function. The efficiency of pollen dispersal (the number of pollen grains per unit donor plant volume dispersed to a given distance) is enhanced by growing on slopes. Males become less efficient at dispersing pollen as they increase in size, while the efficiency of female reproduction (grams of fruit per volume or gram leaf tissue) is unaffected by increasing plant size. The cost to a male of siring a gram of fruit is about the same as the cost to a female of producing the gram of fruit. Implications for the evolution of sexual lability and dioecy are discussed. [ABSTRACT FROM AUTHOR]

Inflamed organs display marked spatial heterogeneity of inflammation, with patches of inflamed tissue adjacent to healthy tissue. To investigate how nanocarriers (NCs) distribute between such patches, we created a mouse model that recapitulates the spatial heterogeneity of the inflammatory lung disease ARDS. NCs targeting the epitope PECAM strongly accumulated in the lungs, but were shunted away from inflamed lung regions due to hypoxic vasoconstriction (HVC). In contrast, ICAM-targeted NCs, which had lower whole-lung uptake than PECAM/NCs in inflamed lungs, displayed markedly higher NC levels in inflamed regions than PECAM/NCs, due to increased regional ICAM. Regional HVC, epitope expression, and capillary leak were sufficient to predict intra-organ of distribution of NCs, antibodies, and drugs. Importantly, these effects were not observable with traditional spatially-uniform models of ARDS, nor when examining only whole-organ uptake. This study underscores how examining NCs' intra-organ distribution in spatially heterogeneous animal models can guide rational NC design., (Copyright © 2017 Elsevier Inc. All rights reserved.)