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This investigation explores novel two‐phase chevron mechanical metamaterials that exhibit auxetic properties. Unlike traditional foam‐like cellular or porous auxetic materials, these designs are composed of chevron patterned layers embedded in anisotropic matrix. This innovation design allows for auxeticity in two orthogonal in‐plane directions (bi‐auxeticity) or in all in‐plane directions (complete auxeticity), providing not only a general strategy but also detailed guidelines for designing non‐porous auxetic mechanical metamaterials with tunable auxetic behaviors. One goal of this work is to explore the mechanical behavior, specifically effective stiffness and Poisson's ratio, of these new designs and to identify the design space for auxetic behavior using numerical and experimental methods. Systematic finite element (FE) simulations are conducted using ABAQUS and Python scripts to quantify effective stiffness and Poisson's ratio within a small strain range. To validate the numerical predictions, three representative designs are selected and fabricated via multi‐material polymer jetting. Uniaxial tension experiments are conducted on these specimens. Design spaces for non‐auxeticity, partial‐auxeticity, and complete auxeticity are identified through an integrated numerical approach. Theoretical criteria for determining the completeness of auxeticity are proposed and verified via FE simulations. [ABSTRACT FROM AUTHOR]

Aims: To investigate the exposure–response (E‐R) relationship, including exposure–efficacy and exposure–safety, of ropeginterferon alfa‐2b treatment in patients with polycythaemia vera (PV). Methods: Based on the results of the phase II trial A20‐202 regarding ropeginterferon alfa‐2b in patients with PV, E‐R analyses were performed to evaluate the efficacy and safety of the given dosing regimen. The E‐R analyses were based on logistic and linear regression and the relationship between exposure to ropeginterferon alfa‐2b and key efficacy and safety variables. The key efficacy variables included complete haematologic response (CHR) and reduction of the driver mutation JAK2V617F. The safety variable was treatment‐related adverse events (TRAEs). Results: A clear relationship between the exposure to ropeginterferon alfa‐2b and CHR was observed, with an increase in drug exposure resulting in an increased probability of achieving CHR. Similar CHR probabilities were observed in the third and fourth quantiles of the average concentration at Week 24. The results from the exposure–JAK2V617F model indicated that the JAK2V617F allele burden decreased with increasing exposure to ropeginterferon alfa‐2b and baseline body surface area. Exposure–safety analysis revealed a risk of AEs associated with transaminase abnormalities, which were not associated with clinical significance. Conclusions: Our analyses have shown that patients with PV treated with ropeginterferon alfa‐2b had an increased probability of achieving CHR and a molecular response with acceptable safety risks at the 250–350–500 μg titration dosing regimen. This study has provided the relevant data for the application of a biologics licence of ropeginterferon alfa‐2b for PV treatment in China. [ABSTRACT FROM AUTHOR]

Tiger nuts (Cyperus esculentus L.) have been widely cultivated as a bioenergy crop in northern China. The value of tubers is receiving special attention, but the lack of information on how organs of tiger nuts coordinate resources to adapt to arid environments has limited the potential tuber production and diverse use. To address this knowledge gap, we experimented in the Ulan Buh Desert, Inner Mongolia (106° 33′ 28″ E, 40° 27′ 32″ N). Three fertilizer treatments were applied: zero fertilizer (N:P = 0:0), traditional fertilizer (N:P = 15:15), and additional nitrogen fertilizer (N:P = 60:15). Investigations were conducted at seedling, rhizome production, tuber formation, and tuber maturation stages. The results showed that under zero fertilizer, tiger nuts allocated biomass predominantly to propagative organs, namely rhizomes and tubers. However, an increase in leaf area or root surface area would necessitate more investment in leaf or root dry mass, resulting in diminishing returns. For biomass allocation, tiger nut responded the same way to traditional fertilizer treatment and zero fertilizer treatment, but the tuber number and yield increase under traditional fertilizer application. Additional nitrogen fertilizer stimulated shoot production through accelerated rhizome production aided by leaf area increasing. Fertilizer application can significantly increase both the number of tiger nuts and tuber yield. Nitrogen addition positively influenced aboveground biomass and enhanced rhizome tillering. Strong adaptability of tiger nuts makes the plant a suitable pioneer crop for developing marginal lands. The robust aboveground growth after nitrogen application enhances suitability for pasture utilization. Core Ideas: Tiger nuts have been promoted as a bioenergy crop in Inner Mongolia, with potential uses yet to be explored.Tiger nuts demonstrate strong adaptability in arid areas, enabling them to thrive in nutrient‐deficient conditions.Tiger nuts with strong adaptability can fully exploit their production potential in marginal lands of Inner Mongolia.Nitrogen fertilizer application plays a major role in biomass partitioning in tiger nuts in an arid ecosystem. [ABSTRACT FROM AUTHOR]

Phosphatases are important regulators of protein phosphorylation and various cellular processes, and they serve as counterparts to kinases. In this study, our comprehensive analysis of oomycete complete proteomes unveiled the presence of approximately 3833 phosphatases, with most species estimated to have between 100 and 300 putative phosphatases. Further investigation of these phosphatases revealed a significant increase in protein serine/threonine phosphatases (PSP) within oomycetes. In particular, we extensively studied the metallo‐dependent protein phosphatase (PPM) within the PSP family in the model oomycete Phytophthora sojae. Our results showed notable differences in the expression patterns of PPMs throughout 10 life stages of P. sojae, indicating their vital roles in various stages of oomycete pathogens. Moreover, we identified 29 PPMs in P. sojae, and eight of them possessed accessory domains in addition to phosphate domains. We investigated the biological function of one PPM protein with an extra PH domain (PPM1); this protein exhibited high expression levels in both asexual developmental and infectious stages. Our analysis confirmed that PPM1 is indeed an active protein phosphatase, and its accessory domain does not affect its phosphatase activity. To delve further into its function, we generated knockout mutants of PPM1 and validated its essential roles in mycelial growth, sporangia and oospore production, as well as infectious stages. To the best of our knowledge, this study provides the first comprehensive inventory of phosphatases in oomycetes and identifies an important phosphatase within the expanded serine/threonine phosphatase group in oomycetes. [ABSTRACT FROM AUTHOR]

Hybrid chiral mechanical metamaterials with center squares connecting by bi‐layer strips (bi‐strips) with patterned interfaces are designed and fabricated via multimaterial 3D printing. Due to the thermal mismatch between the bi‐strips and the chirality‐induced rotation, the designs will undergo either thermal expansion or shrinkage under constant temperature increase, resulting in widely tuned overall thermal expansion coefficients (CTEs) for the chiral mechanical metamaterials. Analytical models of both the bi‐strips with arbitrary dissimilar interface morphology and the chiral designs under temperature change are developed to predict the curvature of the bi‐strips and the overall CTEs of the chiral designs. Two design regions with opposite trends are observed and explored. The models are verified via systematic finite element (FE) simulations and experiments on 3D‐printed specimens. This investigation enlarges the design space of chiral mechanical metamaterials for achieving desired CTEs in a wide range. [ABSTRACT FROM AUTHOR]

(B) Neutralization of different SARS-CoV-2 variant PsVs by sera collected at preboost, as well as 2 months and 4 months after the booster vaccination following the Delta breakthrough infection. RBD, receptor-binding domain. gl In summary, we observed limited enhancement of antibody and B-cell responses to prototype booster vaccination following SARS-CoV-2 Delta breakthrough infection. Limited enhancement of antibody and B-cell responses to prototype booster vaccination following SARS-CoV-2 Delta breakthrough infection. [Extracted from the article]

Phytophthora sojae is an important model species for oomycete functional genomics research. Recently, a CRISPR/Cas9‐mediated genome‐editing technology has been successfully established in P. sojae, which has been rapidly and widely applied in oomycete research. However, there is an emerging consensus in the biological community that a complete functional gene research system is needed such as developed in the investigations in functional complementation carried out in this study. We report the development of an in situ complementation method for accurate restoration of the mutated gene. We targeted a regulatory B‐subunit of protein phosphatase 2A (PsPP2Ab1) to verify this knockout and subsequent complementation system. We found that the deletion of PsPP2Ab1 in P. sojae leads to severe defects in vegetative hyphal growth, soybean infection, and loss of the ability to produce sporangia. Subsequently, the reintroduction of PsPP2Ab1 into the knockout mutant remedied all of the deficiencies. This study demonstrates the successful implementation of an in situ complementation system by CRISPR/Cas9, which will greatly accelerate functional genomics research of oomycetes in the post‐genomic era. [ABSTRACT FROM AUTHOR]

The interfacial strength between explosive crystal and binder usually plays a key role in exhibiting excellent mechanical properties of composite explosives. In this paper, high energetic crystal octahydro‐1,3,5,7‐tetranitro‐1,3,5,7‐tetrazocine (HMX) was coated by the typical binder cis‐1,4‐polybutadiene rubber (BR), then two silane coupling agents were added to the composite particles to enhance the interface strength. The results showed that the BR binder modified by silane coupling agent is easier to spread on the surface of HMX crystal, and form a good coating effect. In the mechanical properties test of composite particles, (3‐Aminopropyl) trimethoxysilane significantly improved the tensile and compressive strength of HMX/BR based composite particles, while 3‐(Triethoxysilyl) propionitrile decreased the mechanical properties of the composite particles. [ABSTRACT FROM AUTHOR]

To improve the ignition and combustion properties of n‐Al powders, n‐Al/Ni composite particles were prepared by replacement reaction under alkaline environment. In the anhydrous ethanol system, the effect of solution parameters on sample preparation was studied, and the preparation technology of n‐Al/Ni was accordingly optimized. The chemical constituents, phase, morphology and combustion performances of n‐Al/Ni were characterized by chemical titration, XRD, SEM, EDS and combustion duration test, respectively. The results showed that the optimized replacement reaction method can modify the n‐Al powders by nickel well, and it was appropriate to use OH−1 corresponding to consume 60 % alumina in the n‐Al powders and Ni2+ equal to 12.35 % mass fraction of n‐Al powders. It can be seen from the SEM images that the samples have a dispersive spherical morphology with a uniform distribution of nickel overall the samples. And the XRD results confirmed that nickel exists in the samples as a metallic substance. The results of chemical titration indicated that the content of active aluminum in the optimal sample was slightly higher than that of raw n‐Al, but considering Ni, the content of reactive substance in the sample was greatly increased. The combustion duration test also proved that the combustion performance of n‐Al/Ni was significantly improved. In conclusion, the improved properties promise a further enhanced prospect of n‐Al in energetic materials. [ABSTRACT FROM AUTHOR]

Nanochannel gating exists extensively in biological systems and has wide applications in nanofluidic studies. Magnetic control is non‐contact and penetrative compared to chemical or electrical gating. This work introduces the fabrication of magnetically gated single nanochannels by grafting superparamagnetic nanoparticles, via bridging of DNA single strands, onto the inner surface of the PET nanochannels which were prepared by single ion hit and ion track etching. The nanochannel showed sub‐second magnetic response with an ON/OFF ratio of 18 measured by ionic conductance under control with a permanent magnet. These magnetically gated single PET nanochannel are speficically advantageous for superficial drug‐delivery and non‐contact control in nanofluidic applications. [ABSTRACT FROM AUTHOR]

Evaporation‐induced self‐assembly of colloidal particles is one of the most versatile fabrication routes to obtain large‐area colloidal crystals; however, the formation of uncontrolled "drying cracks" due to gradual solvent evaporation represents a significant challenge of this process. While several methods are reported to minimize crack formation during evaporation‐induced colloidal assembly, here an approach is reported to take advantage of the crack formation as a patterning tool to fabricate microscopic photonic structures with controlled sizes and geometries. This is achieved through a mechanistic understanding of the fracture behavior of three different types of opal structures, namely, direct opals (colloidal crystals with no matrix material), compound opals (colloidal crystals with matrix material), and inverse opals (matrix material templated by a sacrificial colloidal crystal). This work explains why, while direct and inverse opals tend to fracture along the expected {111} planes, the compound opals exhibit a different cracking behavior along the nonclose‐packed {110} planes, which is facilitated by the formation of cleavage‐like fracture surfaces. The discovered principles are utilized to fabricate photonic microbricks by programming the crack initiation at specific locations and by guiding propagation along predefined orientations during the self‐assembly process, resulting in photonic microbricks with controlled sizes and geometries. [ABSTRACT FROM AUTHOR]

Summary: Chitin is a structural and functional component of the fungal cell wall and also serves as a pathogen‐associated molecular pattern (PAMP) that triggers the innate immune responses of host plants. However, no or very little chitin is found in the fungus‐like oomycetes. In Phytophthora spp., the presence of chitin has not been demonstrated so far, although putative chitin synthase (CHS) genes, which encode the enzymes that synthesize chitin, are present in their genomes. Here, we revealed that chitin is present in the zoospores and released sporangia of Phytophthora, and this is most consistent with the transcriptional pattern of PcCHS in Phytophthora capsici and PsCHS1 in Phytophthora sojae. Disruption of the CHS genes indicated that PcCHS and PsCHS1, but not PsCHS2 (which exhibited very weak transcription), have similar functions involved in mycelial growth, sporangial production, zoospore release and the pathogenesis of P. capsici and P. sojae. We also suggest that chitin in the zoospores of P. capsici can act as a PAMP that is recognized by the chitin receptors AtLYK5 or AtCERK1 of Arabidopsis. These results provide new insights into the biological significance of chitin and CHSs in Phytophthora and help with the identification of potential targets for disease control. [ABSTRACT FROM AUTHOR]

This study focuses on developing an optimal setting method for the first integrated coking flue gas desulphurization and denitration device in China. Maintaining the denitration process in a state of optimal economic efficiency has become an issue in production optimization control. This paper proposes a data‐based two‐stage nonparametric optimization method to optimize the operation of the denitration process. A principal component regression (PCR)‐based multiple case fusion case‐based reasoning (CBR) method is proposed to obtain the initial optimization set points. To overcome the steady‐state modelling difficulties associated with the process, a local modelling method for the coking flue gas denitration process is developed using an improved just‐in‐time learning (JITL) algorithm. Taking the preset values obtained above as the initial value of an active set algorithm, the optimization problem can be solved in a timely and precise manner. The intelligent setting software has been developed for running industrial applications, and the results demonstrate the effectiveness of the proposed optimization approach. [ABSTRACT FROM AUTHOR]

In this paper, we determine the Fujita critical exponent of the following time fractional subdiffusion equation with nonlinear memory 0CDtαu−△u=0It1−γ|u|p−1u,x∈RN,t>0,u(0,x)=u0(x),x∈RN,where 0 < α < 1, 0 ≤ γ < 1, γ ≤ α, p > 1, u0∈C0RN, 0It1−γ denotes left Riemann‐Liouville fractional integral of order 1 − γ. Let β = 1 − γ. We prove that, if 1 p∗ and ‖u0‖LqcRN is sufficiently small, where qc=Nα(p−1)2(α+β), then u exists globally. [ABSTRACT FROM AUTHOR]

New hybrid auxetic chiral mechanical metamaterial are designed and fabricated via multi‐material 3D printing. Due to the chirality‐induced rotation, the material have unique sequential cell‐opening mechanisms. Mechanical experiments on the 3D printed prototypes and systematic FE simulations show that the effective stiffness, the Poisson's ratio and the cell‐opening mechanisms of the new design can be tuned in a very wide range by tailoring two non‐dimensional parameters: the cell size ratio and stiffness ratio of component materials. As example applications, sequential particle release mechanisms and color changing mechanisms of the new designs are also systematically explored. The present new design concepts can be used to develop new multi‐functional smart composites, sensors and/or actuators which are responsive to external load and/or environmental conditions for applications in drug delivery and color changing for camouflage. [ABSTRACT FROM AUTHOR]

For the first time, the concept of amplifying chirality-induced auxetic effect via elevating internal rotation efficiency is proposed. Based on this concept, new chiral cellular solids with center cores and softer hinges are designed and fabricated via multi-material 3D printing. The new designs are proved via mechanical experiments and finite element (FE) simulations to have robust and amplified auxetic effects under large deformation. A linear relationship between the internal rotation efficiency and the Poisson's ratio is discovered. To bridge the conceptual model and the real cellular solids, systematic FE simulations are performed and provided guidelines to design this new family of chiral cellular solids with robust auxetic effects via jointly tailoring geometry and material composition. [ABSTRACT FROM AUTHOR]

Wrinkling vs. long‐wavelength instability envelope for multi‐layered soft composite: Predictive analytical and finite element models are presented to reveal the instability mechanics governing reversible wrinkling of interfacial layers. The biomimetic guidelines for the design of reversible, tunable, and multi‐functional layered soft composites with transforming interfacial layers are developed and verified via 3D printed prototypes. [ABSTRACT FROM AUTHOR]

Keywords: nanochannels; magnetic gating; magnetic control; ion track EN nanochannels magnetic gating magnetic control ion track 996 996 1 07/04/20 20200701 NES 200701 B A magnetically controlled b conical nanochannel is fabricated by grafting ferroferric oxide nanoparticles into the polyethylene terephthalate (PET) nanochannel via bridging of DNA single strands. The nanochannel can be physically closed/opened to control the ionic/molecular transport in the nanochannel within sub-seconds using a permanent magnet. Nanochannels, magnetic gating, magnetic control, ion track. [Extracted from the article]

Photonic Microbricks: Fabrication of Photonic Microbricks via Crack Engineering of Colloidal Crystals (Adv. Funct. Keywords: colloidal crystals; fracture; nano/microfabrication; self-assembly EN colloidal crystals fracture nano/microfabrication self-assembly 1 1 1 06/27/20 20200625 NES 200625 In article number 1908242, Ling Li and co-workers provide a mechanistic understanding of crack formations during the evaporation-induced self-assembly of colloidal crystals, which allows for rational controlling of the location and orientation of cracks for fabricating photonic microstructures with controlled geometries and sizes. Colloidal crystals, fracture, nano/microfabrication, self-assembly. [Extracted from the article]

Critical biomarkers of disease are increasingly being detected by point‐of‐care assays. Chemiluminescence (CL) and electrochemiluminescence (ECL) are often used in such assays due to their convenience and that they do not require light sources or other components that could complicate or add cost to the system. Reports of these assays often include readers built on a cellphone platform or constructed from low‐cost components. However, the impact the optical design has on the limit of detection (LOD) in these systems remains unexamined. Here, we report a theoretical rubric to evaluate different optical designs in terms of maximizing the use of photons emitted from a CL or ECL assay to improve the LOD. We demonstrate that the majority of cellphone designs reported in the literature are not optimized, in part due to misunderstandings of the optical tradeoffs in collection systems, and in part due to limitations imposed on the designs arising from the use of a mobile phone with a very small lens aperture. Based on the theoretical rubric, we design a new portable reader built using off‐the‐shelf condenser optics, and demonstrate a nearly 10× performance enhancement compared to prior reports on an ECL assays running on a portable chip. [ABSTRACT FROM AUTHOR]

Manual hand counting of parasites in fecal samples requires costly components and substantial expertise, limiting its use in resource‐constrained settings and encouraging overuse of prophylactic medication. To address this issue, a cost‐effective, automated parasite diagnostic system that does not require special sample preparation or a trained user was developed. It is composed of an inexpensive (~US$350), portable, robotic microscope that can scan over the size of an entire McMaster chamber (100 mm2) and capture high‐resolution (~1 μm lateral resolution) bright field images without need for user intervention. Fecal samples prepared using the McMaster flotation method were imaged, with the imaging region comprising the entire McMaster chamber. These images are then automatically segmented and analyzed using a trained convolution neural network (CNN) to robustly separate eggs from background debris. Simple postprocessing of the CNN output yields both egg species and egg counts. The system was validated by comparing accuracy with hand‐counts by a trained operator, with excellent performance. As a further demonstration of utility, the system was used to conveniently quantify drug response over time in a single animal, showing residual disease due to Anthelmintic resistance after 2 weeks. [ABSTRACT FROM AUTHOR]