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Multivesicular bodies are key endosomal compartments implicated in cellular quality control through their degradation of membrane-bound cargo proteins1–3. The ATP-consuming ESCRT protein machinery mediates the capture and engulfment of membrane-bound cargo proteins through invagination and scission of multivesicular-body membranes to form intraluminal vesicles4,5. Here we report that the plant ESCRT component FREE16forms liquid-like condensates that associate with membranes to drive intraluminal vesicle formation. We use a minimal physical model, reconstitution experiments and in silico simulations to identify the dynamics of this process and describe intermediate morphologies of nascent intraluminal vesicles. Furthermore, we find that condensate-wetting-induced line tension forces and membrane asymmetries are sufficient to mediate scission of the membrane neck without the ESCRT protein machinery or ATP consumption. Genetic manipulation of the ESCRT pathway in several eukaryotes provides additional evidence for condensate-mediated membrane scission in vivo. We find that the interplay between condensate and machinery-mediated scission mechanisms is indispensable for osmotic stress tolerance in plants. We propose that condensate-mediated scission represents a previously undescribed scission mechanism that depends on the physicomolecular properties of the condensate and is involved in a range of trafficking processes. More generally, FREE1 condensate-mediated membrane scission in multivesicular-body biogenesis highlights the fundamental role of wetting in intracellular dynamics and organization.

Clathrin-mediated endocytosis is an essential cellular internalization pathway involving the dynamic assembly of clathrin and accessory proteins to form membrane-bound vesicles. The evolutionarily ancient TSET–TPLATE complex (TPC) plays an essential, but ill-defined role in endocytosis in plants. Here we show that two highly disordered TPC subunits, AtEH1 and AtEH2, function as scaffolds to drive biomolecular condensation of the complex. These condensates specifically nucleate on the plasma membrane through interactions with anionic phospholipids, and facilitate the dynamic recruitment and assembly of clathrin, as well as early- and late-stage endocytic accessory proteins. Importantly, condensation promotes ordered clathrin assemblies. TPC-driven biomolecular condensation thereby facilitates dynamic protein assemblies throughout clathrin-mediated endocytosis. Furthermore, we show that a disordered region of AtEH1 controls the material properties of endocytic condensates in vivo. Alteration of these material properties disturbs the recruitment of accessory proteins, influences endocytosis dynamics and impairs plant responsiveness. Our findings reveal how collective interactions shape endocytosis.

Nanxiu Qian. Politics, Poetics, and Gender in Late Qing China: Xue Shaohui and the Era of Reform. Stanford, CA: Stanford University Press, 2015. xvi, 376 pp. Hardcover $65.00, ISBN 978-0-8047-9240-0. [...]

Abstract:This article examines a late Qing woman writer Xu Xishen’s writings titled Chants on the Paintings of Embracing the True. In these poetic and prosaic writings, Xu portrayed her deceased daughters, especially her older daughter, as Daoist female immortals. Xu’s writings were uniquely inspired by twenty paintings based on various dreams. These dreams concern a wide variety of human-immortal encounters between the deceased daughters and the dreamers from the family community, including Xu herself, her husband, extended family members, and maidservants. These writings, involving multiple perspectives and literary genres, will shed light on our understanding of how Daoist imagery played a significant role in a late imperial woman writer’s literary creation.

Electrochemical ion exchange has recently been demonstrated to be a unique method for the preparation of novel cathode materials, which cannot be accessible by traditional direct synthesis routes. In this study, the vanadium borophosphate compound K1.33Na0.67[VO(B2O)(PO4)2(HPO4)]·1.63H2O (KNVBP) with zeolitic framework exhibits fast electrochemical Na+/K+ion exchange when used as cathode material in sodium-ion batteries (SIBs). Ex situ structural analyses and electrochemical measurements confirm that most of the K+ions in the parent KNVBP can be extracted and exchanged by Na+ions after the first charge/discharge cycle. The in situ-generated Na-rich phase shows reversible electrochemical activity at approximately 3.9 V versus Na+/Na with a specific capacity of 52.9 mAh g–1, comparable to 96.2% of the theoretical capacity. Moreover, enhanced ionic diffusion kinetics can be achieved after the Na+/K+exchange. This study provides a valuable insight into the electrochemical ion exchange in polyanion compounds toward application in metal-ion batteries.

The internal factors that affect the flux of inside-out hollow UF (ultra filtration) membrane fiber were simplified as “fiber radial permeability coefficient” and “fiber axial resistance coefficient”. The two coefficients were tested and analyzed by using hydrophilic short fiber and hydrophobic fiber respectively. A filtration mathematical model was successfully developed to describe the operation of the hollow fiber. The sensitivity function of average pure water flux, such as fiber length, inside diameter and permeability coefficient, was established. The influence of single parameter change on pure water flux of membrane fiber was analyzed. The results showed that the longer the film length was, the lower the average flux was; the bigger the wire diameter was, the higher the average flux was; the higher the temperature was, the greater the average flux was; the higher the pressure was, the greater the average flux was.

In this paper, we present a recent approach via variational methods and critical point theory to obtain the existence of periodic solutions for a class of delay Hamiltonian systems on time scales with impulsive effects. The variational principle is given, and some existence theorems and two multiplicity results of periodic solutions are obtained. Finally, one example is presented to illustrate the feasibility and effectiveness of our results. Our results are new even in both the differential equations case and the difference equations case.

AbstractThe conventional strain-softening behaviors which assume the strength parameters as the functions of the plastic strain have been studied using various methods. However, rock-like materials have also been found to manifest pressure-dependent behavior for both elastic and plastic rock masses. The realization of the radial stress was found to be continuous, and gradually increased from supporting stress to in situstress for the circular openings under hydrostatic pressure. The radial stress was spaced as numbers of sections, and each annulus was considered as an ideal plastic rock mass. The close-formed analytical solutions of each annulus can be easily obtained. Therefore, using the displacement continuum and stress boundary conditions, the dimensionless radius corresponding to the spaced radius could be derived. The radial stress and plastic shear strain at the inner radius of the outer adjacent annulus were employed to describe the material property evolution law. Then, the radii could be recursively obtained. Finally, for the conventional strain-softening rock masses, the pressure-dependent elastic rock and elasto-plastic coupling strain-softening rock masses were employed to validate the proposed approach. In this study, having completed the above steps, it was concluded that the results were in accordance with the numerical methods.

Fuji (wielding the planchette, or spirit writing) was in vogue among Ming-Qing literati, and its influence extended into modern times. Existing studies focus on this popular divination itself or on men's writings related to this practice. This article, instead, explores the poetry and prose of a female writer, Qian Xi, and her writing activities associated with this divination. Qian claims that the spirits she communicated with include several female immortals and her deceased husband. Some of the questions the author explores are: What are the characteristics of Qian's writings? What inspired Qian to participate in spirit writing? What role did this practice play in Qian's life and writing? Regarding the emotions, thoughts, and works of Qian, what types of information can spirit writing and corresponding poetic and prosaic compositions provide? Instead of simplifying and disregarding the ritual of wielding the planchette as bizarre, superstitious, or even mad, the author argues that it played a meaningful role in shaping Qian's literary images and enhancing her literary productivity. More important, Qian Xi's strategies of using spirit writing to stimulate her literary creations was significant in meeting her emotional needs, highlighting her identity as a talented woman, and demonstrating the worth of her very existence.

Background: Brain function is thought to rely on complex interactions of dynamic neural systems, which depend on the integrity of structural and functional networks. Focal epilepsy is considered to result from excessive focal synchronization in the network. Synchronization analysis of multichannel electrocorticography (ECoG) contributes to the understanding of and orientation of epilepsy. The aim of this study was to explore the synchronization in multichannel ECoG recordings from patients with neocortical epilepsy and characterize neural activity inside and outside the onset zone. Methods: Four patients with neocortical epilepsy, who became seizure-free for more than 1 year after surgery guided by ECoG monitoring, were included in this study. ECoG data recorded during pre-surgical evaluation were analyzed. Synchronizations in phase and amplitude of different frequency bands between ECoG channels was analyzed using MATLAB. We generated 100 surrogate data from the original ECoG data using Amplitude Adjusted Fourier Transform to calculate the enhanced synchronization. The relationship between synchronization characteristics and seizure onset zone was analyzed. Results: We found synchronization clusters in the 14–30 Hz and 30–80 Hz bands around the onset areas during both interictal and the beginning of ictal periods in all four patients. Conclusions: The enhanced-synchronization clusters play a central role in epilepsy, and may activate the onset areas and contribute to the spreading of epileptiform activity.

In this paper, some sufficient conditions are obtained for the existence of solutions for a fractional differential equation with integral boundary value problem at resonance on the half-line. By constructing a suitable Banach space, defining appropriate operators and using the coincidence degree theory due to Mawhin, some new sufficient conditions are obtained, which generalise and enrich some known results.

We employed item response theory (IRT), specifically using Rasch modeling, to determine the measurement precision of the Fitness-to-Drive Screening Measure (FTDS), a tool that can be used by caregivers and occupational therapists to help detect at-risk drivers. We examined unidimensionality through the factor structure (how items contribute to the central construct of fitness to drive), rating scale (use of the categories of the rating scale), item/person-level separation (distinguishing between items with different difficulty levels or persons with different ability levels) and reliability, item hierarchy (easier driving items advancing to more difficult driving items), rater reliability, rater effects (severity vs. leniency of a rater), and criterion validity of the FTDS to an on-road assessment, via three rater groups (n = 200 older drivers; n = 200 caregivers; n = 2 evaluators). The FTDS is unidimensional, the rating scale performed well, has good person (>3.07) and item (>5.43) separation, good person (>0.90) and item reliability (>0.97), with <10% misfitting items for two rater groups (caregivers and drivers). The intraclass correlation (ICC) coefficient among the three rater groups was significant (.253, p < .001) and the evaluators were the most severe raters. When comparing the caregivers’ FTDS rating with the drivers’ on-road assessment, the areas under the curve (index of discriminability; caregivers .726, p < .001) suggested concurrent validity between the FTDS and the on-road assessment. Despite limitations, the FTDS is a reliable and accurate screening measure for caregivers to help identify at-risk older drivers and for occupational therapy practitioners to start conversations about driving.

The liver plays a central role in metabolism and mediating insulin action. To dissect the effects of insulin on the liver in vivo, we have studied liver insulin receptor knockout (LIRKO) mice. Because LIRKO livers lack insulin receptors, they are unable to respond to insulin. Surprisingly, the most profound derangement observed in LIRKO livers by microarray analysis is a suppression of the cholesterologenic genes. Sterol regulatory element binding protein (SREBP)-2 promotes cholesterologenic gene transcription, and is inhibited by intracellular cholesterol. LIRKO livers show a slight increase in hepatic cholesterol, a 40% decrease in Srebp-2, and a 50–90% decrease in the cholesterologenic genes at the mRNA and protein levels. In control mice, SREBP-2 and cholesterologenic gene expression are suppressed by fasting and restored by refeeding; in LIRKO mice, this response is abolished. Similarly, the ability of statins to induce Srebp-2and the cholesterologenic genes is lost in LIRKO livers. In contrast, ezetimibe treatment robustly induces Srepb-2and its targets in LIRKO livers, raising the possibility that insulin may regulate SREBP-2 indirectly, by altering the accumulation or distribution of cholesterol within the hepatocyte. Taken together, these data indicate that cholesterol synthesis is a key target of insulin action in the liver.

Background: The primary influence of motor symptoms on driving performance remains unclear due to the inconsistent use of various motor rating scales used in prior studies. Objective: This study aimed to determine which of three measures utilized in PD, the Unified Parkinson's Disease Rating Scale (UPDRS) motor section; the Modified Hoehn and Yahr; and the Rapid Paced Walk Test would best predict pass/fail outcomes on a road test in a sample of PD drivers. Methods: All participants (N = 55; 79% men) completed a road test. Receiver Operating Characteristics were then contrasted for all subjects based on assessments from all three disease severity indices. MMSE scores were then modelled with significant disease severity measures (if any) to determine if the predictive accuracy could be improved. Results: The Rapid Paced Walk Test and the Modified Hoehn & Yahr both predicted pass/fail outcomes on the road test (Area under the curve of 0.73 and 0.82, respectively). UPDRS motor scores, however, did not predict safe driving. When optimal cut-off points on the Modified Hoehn & Yahr (≥2.5) and Rapid Paced Walk Test (>6.22 seconds) were modelled with MMSE scores indicative of mild cognitive impairment (<27), the model accurately classified 92% and 100% as failing the road test, respectively. Conclusion: Although the Rapid Paced Walk Test had a slight advantage in differentiating between pass/fail outcomes compared to the Modified Hoehn & Yahr, both tests alone cannot be used in isolation to predict driving safety. Predictive accuracy can be improved using both select cut-off points on the Modified Hoehn & Yahr and Rapid Paced Walk test with MMSE scores in PD drivers. Though these findings are useful, an on-road test is still the gold standard, and screening should always be followed by formal testing.

Race and ethnicity have been shown to influence fractional exhaled nitric oxide (FeNO). There is a need to investigate cutoff points for different races and ethnicities to improve clinical application.

Suspending a mesh cylinder in a tube modulates flow patterns with gas bubbles in the annular region to form thin liquid film on the wall. We investigate the effect of gravity levels on the modulated flow patterns. The volume of fluid (VOF) method simulates the slug bubble train flow in bare tube and modulated flow sections. The bubble population density along the flow direction ( β ) and averaged liquid film thickness ( δ α ) synthesize a parameter β / δ a to characterize the enhancement of phase change heat transfer. It is found that at the normal gravity on earth, counter-flow appears with fast upward flow in the annular region and downward liquid flow in the core region. A lower β due to sparsely populated bubbles and thin liquid film form a larger β / δ a to enhance the phase change heat transfer. Convective heat transfer in liquid plugs is enhanced by the fast fluid movement in the annular region and liquid circulations at three length scales. At the miniature gravity, quasi-co-current flow happens with upward flows in both annular region and core region, except that a liquid layer inside mesh cylinder flows downward. Bubbles are more densely populated than those at the normal gravity. Liquid circulation occurs only at the bubble length scale. At the micro gravity, the two-phases are thoroughly separated with co-current flows in both annular region and core region. Gas flows slowly and the residence time of gas is increased to result in β = 1. Τhe liquid film is ultra-thin. These two factors create a significantly large β / δ a to enhance the phase change heat transfer. We demonstrate the effectiveness of the phase separation concept at miniature and micro gravity environment. [ABSTRACT FROM AUTHOR]