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To date, supercontinuum light in the visible and near‐infrared ranges is readily realizable by the optical Kerr effect through self‐phase modulation of ultrashort laser pulses in transparent media. However, it is still a challenge to extend the supercontinuum spectrum down to the deep‐ultraviolet (DUV) range, which is particularly needed for exploring ultrafast dynamics in chemistry, materials, and biology. Here, an approach of non‐resonant coherent Raman scattering is developed to generate ultra‐broadband visible‐DUV supercontinuum in ambient air with a spectral range spanning over 250 nm and a wavelength down to 220 nm. A rovibrational coherence is established in air molecules by filamentation of a near‐infrared femtosecond 800 nm pulse and two femtosecond Raman laser pulses at 267 and 400 nm are introduced into the coherent media to induce non‐resonant coherent Stokes and anti‐Stokes Raman scatterings, which serve as the spectral bridges to link the neighboring Raman pump laser spectra, resulting in ultra‐broadband supercontinuum light. The mechanism is further verified by examining the broadening of picosecond N2+ laser lines with narrow bandwidths (10–30 cm−1), which forms a supercontinuum spectrum spanning over 150 nm. The work provides a viable route for the establishment of coherent DUV supercontinuum in the gas media at designed wavelength ranges. [ABSTRACT FROM AUTHOR]

In this study, we investigate the relationship between structure and properties of fiber–matrix adhesion for material extrusion–based 3‐dimensional (3D) printed composites. We examine the influence of fiber length and fiber content on the tensile properties of glass, basalt, and carbon fiber–reinforced polylactic acid (PLA) composites. Short fiber–reinforced filaments were produced, then, simple micromechanical models were used to predict the in‐plane tensile properties. We found that interlayer tensile properties are strongly influenced by fiber–matrix adhesion. If adhesion is sufficient, the fibers and matrix deform together under tensile load. A second‐order relationship describes interlayer tensile strength in relation to fiber content between 5 and 25 w%, with a maximum at 15 w%, for carbon and basalt fiber–reinforced composites. If adhesion is weak, the crack propagates along the fiber–matrix interface, causing brittle fracture and low strength. This behavior was noted for the glass fiber composite, for which the calculated interface shear strength was the lowest (1.4 MPa). In this case, fiber content is inversely proportional to interlayer tensile strength. Our results show the role of fiber–matrix adhesion quality on tensile properties, which has a major impact on both the accuracy of predictions and the damage processes. Highlights: Critical fiber length determines accuracy of tensile property estimatesQuality of fiber–matrix adhesion governs interlayer damage processPoor adhesion causes brittle fracture and low strengthSecond‐order relationship of interlayer tensile strength and fiber contentLoss of interlayer tensile strength in composite due to fiber–matrix interface [ABSTRACT FROM AUTHOR]

Enhancing typhoon forecasts hinges on a deeper understanding of the upper‐ocean's response and feedback mechanisms to typhoons. Presently, our knowledge of typhoon‐ocean interactions is largely derived from low‐resolution numerical simulations (often >10 km) and limited observations, which inadequately capture submesoscale processes (SPs) in the ocean. Connecting extreme typhoons to upper‐ocean SPs remains a challenge. This study reveals the formation of a distinctive vortex filament pool (VFP) in high‐resolution (∼1.2 km) numerical experiments. The experiments show that under specific conditions, typhoons can generate this visually striking phenomenon, displaying SP dynamics and kinematics typical of the upper ocean, with Rossby numbers and the nondimensional strain and divergence rates exceeding 2. The VFP formation is mainly driven by strain‐induced frontogenesis linked to the flow generated by Typhoon Nangka after a major turn. Initially, the pool consists of many near‐parallel filaments, but processes such as merging, stretching, and destabilization subsequently occur lead to numerous small vortices with a mean radius of ∼13 km. While the high‐resolution numerical experiments highlight phenomena requiring observational validation, they suggest the presence of natural processes previously undetectable with low‐resolution models and limited observations. This study underscores the need for enhanced observations and numerical models to better understand refined ocean dynamical processes. Plain Language Summary: Our understanding of the upper‐ocean's response and feedback to typhoons is limited by sparse observations and low‐resolution numerical models. High‐resolution numerical simulations have uncovered new features, revealing that under specific conditions, a vortex filament pool can form in the upper ocean following a super typhoon. Analysis shows that these filaments exhibit characteristics typical of upper ocean submesoscale processes. The pool then undergoes interesting processes like merging, stretching, and destabilization, resulting in numerous small vortices. Although these findings need further observational evidence, they highlight possible complex interactions among submesoscale processes. This emphasizes the critical need for better observational tools and enhanced numerical models to identify unfamiliar oceanic phenomena. Key Points: High resolution model results reveal a vortex filament pool left by a super typhoonThe filaments undergo merging, stretching, and eventually breaking into multiple smaller vorticesThe filament pool is produced by the strain‐induced frontogenesis associated with the flow induced by Typhoon Nangka after a major turn [ABSTRACT FROM AUTHOR]

The fabrication of a biodegradable polycaprolactone (PCL)/hydroxyapatite (HAp) scaffold prepared from local waste blue crab shells (Portunus pelagicus) by melt spinning method was investigated. The effect of different KH2PO4 concentrations on the physico‐chemical properties of HAp is evaluated. Furthermore, the influence of PCL/HAp ratios on mechanical strength and particle size distribution is reported. The formation of HAp is confirmed by Infrared (IR) spectroscopy and X‐ray diffraction (XRD). The biocompatibility of the PCL/HAp composites was evaluated using MTT assay and mechanical tests. The results reveal that the increase in KH2PO4 concentration contributed to the higher yield of HAp. However, the crystal and particle sizes are relatively invariable. SEM micrograph shows that the HAp introduction into PCL improves the material's porosity. Moreover, adding 10 % HAp into the PCL matrix significantly improved the mechanical strength of the filament compared to commercial PCL. MTT assay exhibits above 90 % cell viability, implying that the prepared PCL/HAp composite is non‐toxic and biocompatible with artificial bone replacement. After all, this study demonstrates that PCL/HAp filament derived from local blue crab waste is highly promising as a bone scaffolding material. [ABSTRACT FROM AUTHOR]

This study investigates the effects of thermal treatment and silver nanoparticles on the mechanical and thermal properties of additively manufactured wood/polylactic acid (PLA) specimens. The 5 and 10 wt% additions of the wood flour into the PLA matrix are done in the twin screw extruder. The test specimens are produced from the filaments with a diameter of 1.75 mm using 3D printer. The mechanical properties of the 3D‐printed wood/PLA specimens are affected by the wood flour content, thermal treatment of wood, and silver nanoparticles. The 3D‐printed neat PLA specimens have better mechanical properties than the wood flour‐filled PLA specimens. The bending strength of the specimens enhances with increasing wood flour content while the tensile strength decreases. The increases in the mechanical properties reveal that the thermal treatment of the wood improves the compatibility between wood and PLA matrix, which hereby improves the interfacial adhesion. The addition of the silver nanoparticles positively affects the mechanical properties and it is more compatible with thermally modified wood particles as compared to the untreated wood particles. [ABSTRACT FROM AUTHOR]

SUMMARY: Switch defective/sucrose non‐fermentable (SWI/SNF) chromatin remodeling complexes are evolutionarily conserved, multi‐subunit machinery that play vital roles in the regulation of gene expression by controlling nucleosome positioning and occupancy. However, little is known about the subunit composition of SPLAYED (SYD)‐containing SWI/SNF complexes in plants. Here, we show that the Arabidopsis thaliana Leaf and Flower Related (LFR) is a subunit of SYD‐containing SWI/SNF complexes. LFR interacts directly with multiple SWI/SNF subunits, including the catalytic ATPase subunit SYD, in vitro and in vivo. Phenotypic analyses of lfr‐2 mutant flowers revealed that LFR is important for proper filament and pistil development, resembling the function of SYD. Transcriptome profiling revealed that LFR and SYD shared a subset of co‐regulated genes. We further demonstrate that the LFR and SYD interdependently activate the transcription of AGAMOUS (AG), a C‐class floral organ identity gene, by regulating the occupation of nucleosome, chromatin loop, histone modification, and Pol II enrichment on the AG locus. Furthermore, the chromosome conformation capture (3C) assay revealed that the gene loop at AG locus is negatively correlated with the AG expression level, and LFR‐SYD was functional to demolish the AG chromatin loop to promote its transcription. Collectively, these results provide insight into the molecular mechanism of the Arabidopsis SYD‐SWI/SNF complex in the control of higher chromatin conformation of the floral identity gene essential to plant reproductive organ development. Significance Statement: This study provides insight into the molecular mechanism of the Arabidopsis SYD‐SWI/SNF complex in the control of higher chromatin conformation of the floral identity gene essential to plant reproductive organ development. [ABSTRACT FROM AUTHOR]

Present research evaluates the feasibility of producing polyethylene terephthalate glycol (PETG) filaments reinforced with cenosphere (CS), which have great potential to develop syntactic foam composites (SFC) for several applications, that is, from automotive to aerospace. A melt flow extrusion technique was used to reinforce PETG with different weight fractions (i.e., 0, 10, 20, 30, and 40 wt%) cenosphere, and further, the thermal, mechanical, and physical properties of the prepared feedstocks were investigated in detail. Results indicated that Young's modulus, load‐bearing capacity, and ultimate tensile strength of PETG filament with 40 wt% CS were 1652.1 ± 5 MPa, 76.91 ± 1 N, and 31.97 ± 1 MPa, respectively, which is similar to virgin PETG filament. In addition, the porosity of the CS‐reinforced PETG filaments decreased with increasing concentration of the CS in the PETG matrix. Such cenosphere‐filled filaments possess attractive thermo‐mechanical and physical properties to develop high‐quality SFC through additive manufacturing (AM) routine. Highlights: PETG/cenosphere based 3D printing filaments were developed.The modulus and strength significantly improved by adding 40% cenosphere.The porosity decreased with increasing cenosphere weight fraction.Addition of cenosphere affected water absorption characteristics of filaments. [ABSTRACT FROM AUTHOR]

Ocean dynamics at the submesoscale play a key role in mediating upper‐ocean energy dissipation and dispersion of tracers. Observations of ocean currents from synoptic mesoscale surveys at submesoscale resolution (250 m–100 km) from a novel airborne instrument (MASS DoppVis) reveal that the kinetic energy spectrum in the California Current System is nearly continuous from 100 km to sub‐kilometer scales, with a k−2 spectral slope. Although there is not a transition in the kinetic energy spectral slope, there is a transition in the dynamics to non‐linear ageostrophic interactions at scales of O $\mathcal{O}$(1 km). Kinetic energy transfer across spatial scales is enabled by interactions between the rotational and divergent components of the flow field at the submesoscale. Kinetic energy flux is patchy and localized at submesoscale fronts. Kinetic energy is transferred both downscale and upscale from 1 km in the observations of a cold filament. Plain Language Summary: Ocean dynamics at scales of 100 m–10 km, called the submesoscale, are important because they are associated with large velocity gradients and non‐linear interactions. Large gradients lead to vertical velocity, which facilitates ocean‐atmosphere interactions and ocean biological processes. Velocity gradients and non‐linear processes combine to transfer kinetic energy from the large‐scale flow to small‐scale perturbations. This can lead to instabilities that dissipate energy in the ocean surface layer (rather than the seafloor). Here we analyze novel observations that provide insight into ocean dynamics through the distributions of velocity gradients and energy transfer at 1 km scale. Dynamics at these scales have previously been modeled, but have not been observed directly. We observe a transition where non‐linear dynamics become more important at scales of order 10 km. We also introduce new interpretations of spectral analysis (analysis of energy and correlations across scales). Moreover, we analyze covariance of velocity gradient quantities and flow energetics to demonstrate that energy flux is episodic and localized at fronts. Together, these observations demonstrate that fronts play an important role in boundary‐layer kinetic energy processes and highlight the evolution of upwelling filaments. Key Points: Remote sensing observations reveal a kinetic energy spectrum with a continuous slope from 100 to 1 km in an eastern boundary regionBetween 1 and 10 km, ageostrophic non‐linear interactions become dynamically importantCross‐scale kinetic energy transfers computed from 2D velocity observations are associated with shear strain in the observed front [ABSTRACT FROM AUTHOR]

Waste plastic exposed to the environment creates problems and is of significant concern for all life forms. To reuse the waste plastic in a well‐organized manner and make it more productive, extrusion‐based additive manufacturing, specially fused deposition modeling technique, can be an effective way. Hence, the primary objective of this work is to reuse ABS waste for developing sustainable three‐dimensional printing filaments. A mixed feedstock processing approach is used to develop filaments, in which recycled ABS is blended with virgin ABS in weight ratio of 10%–50%. The rheological and thermo‐mechanical properties of the extruded filaments were examined. Results indicated that increasing extrusion temperature from 190°C to 195°C produced significant physical changes in ABS blends. There is a breakdown of styrene acrylonitrile and butadiene component in ABS which causes strain hardening and material stiffening. The Young's modulus, yield strength and ultimate tensile strength of 80% RABS/20% VABS filament were found to be 2329, 34.814 and 40.82 MPa, respectively, which is close to VABS filament. The novel filament produced from recycled/virgin ABS blends has the capability to replace commercially available ABS filaments for fabricating high‐quality plastic parts through an additive manufacturing routine. [ABSTRACT FROM AUTHOR]

The spinnability of poly (p‐phenyl‐oxadiazole) (POD) spinning dope was regulated by tuning intrinsic viscosity and temperature to make it feasible for dry‐jet wet spinning. An increase in intrinsic viscosity ([η]) and a decrease in temperature will give rise to a more significant entanglement density of the POD solution and increase viscosity. Results show that POD spinning dopes' stable extrusion can be formed at the conditions when the spinning dope's viscoelastic transition frequency (VETF) is around 10 Hz. The solution was selected to prepare POD fiber when [η] = 2.23 at 40 °C, and the tensile strength of the POD fiber was enhanced significantly (from 1.3 to 3.19 cN/dtex). The best mechanical properties were achieved when the draw ratio at the spinneret was 1.6. Our work provides an alternative for the rapid preparation of high‐performance POD fiber, which is of great significance for broadening the application field of POD fibers. [ABSTRACT FROM AUTHOR]

Additive manufacturing is accelerating in hypersonic speed, which touched upon almost all the nook and corners of the manufacturing sector. The present stage wherein a 3D printer is capable of printing queer hybrid materials was not imagined through conventional manufacturing albeit it is meager existence in a few instances. Its expendable arms stretch to the maximum level that is even clearly addressed in Industry 4.0 too, by making at least a printer in a company for printing specific customized materials. The dream of printing composite material was been a long‐term goal for researchers worldwide. This article primarily focuses on this niche area of printing natural fiber composite materials that too specifically jute fiber‐reinforced composites. Very few pieces of literature are available on additive manufacturing of specific natural fibers. As the technique for printing natural fiber‐reinforced composites is still under evolution, this study will be more interesting as it consolidates the facts and figures involved in 3D of jute fiber reinforced composites alone. Different forms of jute fibers used by the researchers include weaved jute, jute as continuous fiber, filament along with jute, jute fiber as reinforcement, jute used as rope as well as jute fiber as cement matrix and all these forms have been addressed in this review. [ABSTRACT FROM AUTHOR]

The feasibility of preparing a novel wet‐spun multifilament derived from paramylon‐a linear β‐1,3‐glucan‐is investigated in this study. The decomposition temperature of the paramylon multifilament (∼300 °C) exceeds that of a wet‐spun cellulose one (∼270 °C). The distinctive feature of the paramylon multifilament is that its moisture regain is considerably higher than that of the cellulose multifilament (∼16 % vs ∼11 %). Scanning electron microscopy (SEM) observations of a homogenized aqueous dispersion containing paramylon multifilaments revealed that the shear‐force‐resistant and water‐insoluble fibrils detach from the paramylon multifilament, whereas the cellulose filament remains almost intact. SEM images provided two insights. First, the paramylon filament comprises many fibrils. Second, the adhesion between fibrils is susceptible to water molecules. The higher moisture regain is ascribable to this assembly architecture, i. e., the adhesion between the fibrils decreases upon exposure to moisture, which increases the surface area and fosters much more water absorption than that in the cellulose filament. [ABSTRACT FROM AUTHOR]

Microwave Interferometer in the Limiter Shadow (MILS) is a new diagnostic, installed on ASDEX Upgrade for electron density measurements in the far Scrape‐Off Layer (SOL). At the chosen frequency of 47 GHz, the region of measurements varies within several centimetres before and after the limiter, depending on the density. 200 kHz bandwidth allows resolving transient events such as edge localized modes filaments and turbulence filaments. The measured quantities, phase shift, and power decay of the microwave beam, which crosses the plasma, are directly connected to the density and do not depend on any other plasma quantity. In this work, we analyse the influence of a filamentary perturbation on MILS signals. Simple representation of a filament is adopted, with parameters relevant to experimental filament properties, reported for ASDEX Upgrade. Forward modelling is done in COMSOL software by using RAPLICASOL, to study the response of the MILS synthetic diagnostic to the presence of a filament. Qualitative and quantitative dependencies are obtained and the boundaries of MILS sensitivity to filaments, or to the density perturbation in far SOL in general, are outlined. [ABSTRACT FROM AUTHOR]

Desminopathy is the most common intermediate filament disease in humans. The most frequent mutation causing desminopathy in patients is a R350P DES missense mutation. We have developed a rat model with an analogous mutation in R349P Des. To investigate the role of R349P Des in mechanical loading, we stimulated the sciatic nerve of wild‐type littermates (WT) (n = 6) and animals carrying the mutation (MUT) (n = 6) causing a lengthening contraction of the dorsi flexor muscles. MUT animals showed signs of ongoing regeneration at baseline as indicated by a higher number of central nuclei (genotype: P < .0001). While stimulation did not impact central nuclei, we found an increased number of IgG positive fibers (membrane damage indicator) after eccentric contractions with both genotypes (stimulation: P < .01). Interestingly, WT animals displayed a more pronounced increase in IgG positive fibers with stimulation compared to MUT (interaction: P < .05). In addition to altered histology, molecular signaling on the protein level differed between WT and MUT. The membrane repair protein dysferlin decreased with eccentric loading in WT but increased in MUT (interaction: P < .05). The autophagic substrate p62 was increased in both genotypes with loading (stimulation: P < .05) but tended to be more elevated in WT (interaction: P = .05). Caspase 3 levels, a central regulator of apoptotic cell death, was increased with stimulation in both genotypes (stimulation: P < .01) but more so in WT animals (interaction: P < .0001). Overall, our data indicate that R349P Des rats have a lower susceptibility to structural muscle damage of the cytoskeleton and sarcolemma with acute eccentric loading. [ABSTRACT FROM AUTHOR]

In recent years, the rise of antibiotic resistance has become a primary health problem. With the emergence of bacterial resistance, the need to explore and develop novel antibacterial drugs has become increasingly urgent. Filamentous temperature‐sensitive mutant Z (FtsZ), a crucial cell division protein of bacteria, has become a vital antibacterial target. FtsZ is a filamentous GTPase; it is highly conserved in bacteria and shares less than 20% sequence identity with the eukaryotic cytoskeleton protein tubulin, indicating that FtsZ‐targeting antibacterial agents may have a low cytotoxicity toward eukaryotes. FtsZ can form a dynamic Z‐ring in the center of the cell resulting in cell division. Furthermore, disturbance in the assembly of FtsZ may affect cellular dynamics and bacterial cell survival, making it a fascinating target for drug development. This review focuses on the recent discovery of FtsZ inhibitors, including peptides, natural products, and other synthetic small molecules, as well as their mechanism of action, which could facilitate the discovery of novel FtsZ‐targeting clinical drugs in the future. [ABSTRACT FROM AUTHOR]

Inflammasomes are cytosolic multimeric signaling complexes of the innate immune system that induce activation of caspases. The NOD‐like receptor NLRP9 recruits the adaptor protein ASC to form an ASC‐dependent inflammasome to limit rotaviral replication in intestinal epithelial cells, but only little is known about the molecular mechanisms regulating and driving its assembly. Here, we present the crystal structure of the human NLRP9 pyrin domain (PYD). We show that NLRP9PYD is not able to self‐polymerize nor to nucleate ASC specks in HEK293T cells. A comparison with filament‐forming PYDs revealed that NLRP9PYD adopts a conformation compatible with filament formation, but several charge inversions of interfacing residues might cause repulsive effects that prohibit self‐oligomerization. These results propose that inflammasome assembly of NLRP9 might differ largely from what we know of other inflammasomes. [ABSTRACT FROM AUTHOR]

Natural silk is considered as queen of textile due to its superior traits. This study was conducted to assess technical properties of cocoon, and raw silk and mechanical properties of silk filament produced by two mulberry silkworm strains. The Chinese strain (205PO) produced dry cocoon of 0.61±0.04 g with raw silk of 0.30±0.02 g and the Japanese strain (J101) produced dry cocoon of 0.49±0.01 g with raw silk of 0.23±0.00 g. The single filament length of 205PO and J101 was 1203.1±20.42 m cocoon−1 and 1082.3±48.95 m cocoon−1, respectively. The filament was finer in the Japanese silkworm strain (1.91±0.06 denier) compared to the Chinese silkworm strain (2.26±0.15 denier). The filament tenacity, tenacity rupture and strain of J101 was 6.24 %, 24.62 % and 4.42 % greater compared to 205PO. The tensile strength of 205PO was 11.82 % greater compared to J101. The filament diameter was 22.01±0.42 μm and 21.98±0.15 μm of 205PO and J101, respectively. Based on these findings, it is recommended that silkworm strains with superior techno‐mechanical properties may be included in breeding programmes for enhancing the quality of silk textile. [ABSTRACT FROM AUTHOR]

The article presents several case studies related to the Bacterial filamentation during findings in cutaneous pathology. Information on the case study of a 56-year-old female with multiple myeloma and a history of an autologous and T-cell depleted allogeneic hematopoietic stem cell transplant who presented with cellulitis on the nose. It also discusses the 44-year-old male with a history of left testicular nonseminomatous germ cell tumor and autologous hematopoietic stem cell transplant.

Abstract: Submesoscale flows are energetic motions on scales of several kilometers that may lead to substantial vertical motions. Here we present satellite and ship radar as well as underway conductivity‐temperature‐depth and Acoustic Doppler Current Profiler observations of a cyclonic submesoscale filament in the marginal ice zone of Fram Strait. The filament created a 500‐m thin and 50‐km long sea ice streak and extends to >250‐m depth with a negative/positive density anomaly within/below the halocline. The frontal jets of 0.5 m/s are in turbulent thermal wind balance while the ageostrophic secondary circulation in places appears to subduct Atlantic Water at >50 m/day. Our study reveals the submesoscale dynamics related to sea ice shapes that can be sensed remotely and shows how submesoscale dynamics contribute to shaping the marginal ice zone. It also demonstrates the co‐occurrence and mixing of water masses over short horizontal scales, which has implications for ocean and sea ice models and understanding of patch formation of planktonic organisms. [ABSTRACT FROM AUTHOR]

LED lighting is predicted to constitute 70% of the outdoor and residential lighting markets by 2020. While the use of LEDs promotes energy and cost savings relative to traditional lighting technologies, little is known about the effects these broad-spectrum 'white' lights will have on wildlife, human health, animal welfare, and disease transmission. We conducted field experiments to compare the relative attractiveness of four commercially available 'domestic' lights, one traditional (tungsten filament) and three modern (compact fluorescent, 'cool-white' LED and 'warm-white' LED), to aerial insects, particularly Diptera. We found that LEDs attracted significantly fewer insects than other light sources, but found no significant difference in attraction between the 'cool-' and 'warm-white' LEDs. Fewer flies were attracted to LEDs than alternate light sources, including fewer Culicoides midges (Diptera: Ceratopogonidae). Use of LEDs has the potential to mitigate disturbances to wildlife and occurrences of insect-borne diseases relative to competing lighting technologies. However, we discuss the risks associated with broad-spectrum lighting and net increases in lighting resulting from reduced costs of LED technology. [ABSTRACT FROM AUTHOR]

Three types of lignin/poly(ethylene oxide) (PEO) blend filaments with different PEO percent were prepared by melt spinning. The effects of PEO percent and lignin type on the morphology, mechanical property, and thermostability of the blend filaments were systematically studied. The morphologies of the filaments were observed by optical microscope. The mechanical properties of the filaments were measured with an Instron model Isx. The results showed that the effect of lignin/PEO blending ratio was not a simple function of PEO content. The flexibility of the lignin/PEO filament increases as thermal stability decreases. A 15% PEO content produces the best combination of filament performance, such as uniform diameter, smooth surface, adequate mechanical property, and thermal stability. [ABSTRACT FROM AUTHOR]

ABSTRACT Experiments with stretching moderately concentrated polymer solutions have been carried out. Model experiments were carried out for poly(acrylonitrile) solutions in dimethyl siloxane. Just the choice of concentrated solutions allowed for a clear demonstration of a demixing effect with the formation of two separate phases-an oriented polymer fiber and solvent drops sitting on its surface. An original experimental device for following all subsequent stages in the demixing process was built. It combined two light beams, one transverse to the fiber and a second directed along (inside) the fiber, the latter played the role of an optical line. This gives a unique opportunity to observe processes occurring inside a fiber. The process of demixing starts from the volume phase separation across the whole cross section of a fiber at some critical deformation and the propagation of the front of demixing along the fiber. Then a solvent cylindrical skin appears which transforms into a system of separate droplets. New experimental data are discussed based on a comparison of the current different points of view on the phenomenon of deformation-induced phase separation: thermodynamic shift of the equilibrium phase transition temperature, growth of stress-induced concentration fluctuations in two-component fluids, and mechanically pressing a solvent out from a polymer network. The general belief is that a rather specific (so-called 'beads-on-a-string') structure of a filament is realized in stretching dilute solutions: beads of a polymer solution connected by oriented polymer bridges forming a single object. The situation in stretching moderately concentrated solutions appears quite different: real phase separation was observed. So, the alternative phenomenon to the formation of the 'beads-on-a-string' structure has been experimentally proven. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015, 53, 559-565 [ABSTRACT FROM AUTHOR]

In this work, we propose an adaptive subdivision piecewise linear interface calculation (PLIC) for 2D multimaterial hydrodynamic simulation codes. Classical volume-of-fluid PLIC technique uses one line segment and one given normal to separate two materials. Unfortunately, these paradigms are not sufficient when filaments occur, leading to the creation of flotsam and jetsam. We propose to detect such situations and to split the computational mixed cell into reconstruction subzones. Within these subzones, one computes a so-called subgradient using an incomplete stencil of neighbors, and the material is distributed in these subzones. Given subzone volume fraction and the subgradient, one computes one line segment using classical PLIC method, leading to a modified PLIC method for subscale material entity. The subdivision procedure relies on a splitting point, which is chosen as a specific information about the relative location of the filament in the cell, leading to an adaptive subdivision for PLIC reconstructions. Numerical tests are carried out in a 2D Lagrange + Remap multimaterial hydrodynamics Eulerian code. Static and dynamic filaments and fragments are simulated in advection or stretched in vortex-like motion. The full hydrodynamics equations are solved on a more realistic test (shock-bubble impact). Results show that our approach supplements classical PLIC method for situations when filaments and fragments occur. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT Chirality of amyloid fibrils-linear beta-sheet-rich aggregates of misfolded protein chains-often manifests in morphological traits such as helical twist visible in and in chiroptical properties accessible to vibrational circular dichroism (VCD). According to recent studies the relationship between molecular chirality of polypeptide and superstructural chirality of amyloid fibrils may be more intricate and less deterministic than previously assumed. Several puzzling experimental findings have put into question earlier intuitive ideas on: 1) the bottom-up chirality transfer upon amyloidogenic self-assembly, and 2) the structural origins of chiroptical properties of protein aggregates. For example, removal of a single amino acid residue from an amyloidogenic all-L peptide was shown to reverse handedness of fibrils. On the other hand, certain types of amyloid aggregates revealed surprisingly strong VCD spectra with the sign and shape dependent on the conditions of fibrillation. Hence, microscopic and chiroptical studies have highlighted chirality as one more aspect of polymorphism of amyloid fibrils. This brief review is intended to outline the current state of research on amyloid-like fibrils from the perspective of their structural and superstructural chirality and chiroptical properties. Chirality 26:220-227, 2014. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Biodegradable polymeric scaffolds have been widely used in tissue engineering as a platform for cell proliferation and subsequent tissue regeneration. Conventional microextrusion methods for three-dimensional (3D) scaffold fabrication were limited by their low resolution. Electrospinning, a form of electrohydrodynamic (EHD) printing, is an attractive method due to its capability of fabricating high-resolution scaffolds at the nanometer/micrometer scale level. However, the scaffold was composed of randomly orientated filaments which could not guide the cells in a specific direction. Furthermore, the pores of the electrospun scaffold were small, thus preventing cell infiltration. In this study, an alternative EHD jet printing (E-jetting) technique has been developed and employed to fabricate 3D polycaprolactone (PCL) scaffolds with desired filament orientation and pore size. The effect of PCL solution concentration was evaluated. Results showed that solidified filaments were achieved at concentration >70% (w/v). Uniform filaments of diameter 20 μm were produced via the E-jetting technique, and X-ray diffraction and attenuated total reflectance Fourier transform infrared spectroscopic analyses revealed that there was no physicochemical changes toward PCL. Scaffold with a pore size of 450 μm and porosity level of 92%, was achieved. A preliminary in vitro study illustrated that live chondrocytes were attaching on the outer and inner surfaces of collagen-coated E-jetted PCL scaffolds. E-jetted scaffolds increased chondrocytes extracellular matrix secretion, and newly formed matrices from chondrocytes contributed significantly to the mechanical strength of the scaffolds. All these results suggested that E-jetting is an alternative scaffold fabrication technique, which has the capability to construct 3D scaffolds with aligned filaments and large pore sizes for tissue engineering applications. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2014:102B:651-658. [ABSTRACT FROM AUTHOR]

Organised mineralised structures observed in large inoceramids (valves on a metre scale) from the Late Albian, Toolebuc Formation, Australia ( Inoceramus sutherlandi Mc Coy, 1865), and the Santonian, Niobrara Formation, USA ( Platyceramus sp.), were investigated using variable pressure scanning electron microscope ( SEM) with energy-dispersive X-ray spectroscopy ( EDX), X-ray microcomputed tomography (micro- CT) and X-ray diffraction ( XRD) analyses. These indicate that the structures comprised a phosphate framework of aligned tubes and shallow troughs overlain perpendicularly by evenly spaced structures. In the Toolebuc Inoceramus, these are U-shaped cross-structures, whilst in the Niobrara Platyceramus, they comprise bundled fibre elements. Comparison with modern bivalves indicates that the observed phosphatised structures represent soft-tissue preservation of the gills, as suggested in earlier publications. The tubes and troughs are remnants of a filamental support framework comprising ordinary and primary filaments, whilst the U-shaped cross-structures ( I. sutherlandi) and fibrous bands ( Platyceramus) represent preserved longitudinal gill musculature. Internal perforate and strand-like fabric observed on the internal surface of some Platyceramus tubular structures suggests that the framework comprised collagen. The presence of primary and ordinary filaments in numerous unusually large plicae, in at least two lamellae, indicates that the gill structures were heterorhabdic. Each plica has at least 40 ordinary filaments, an exceptional number when compared with the maximum of 20 present in modern heterorhabdic gills. The absence of incontrovertible interfilament junctions makes it difficult to say whether inoceramids were filibranch, pseudolamellibranch or eulamellibranch. However, structures that are best attributed to intraplical junctions between filaments suggest the Inoceramidae had gills akin to those of pseudolamellibranch bivalves, although their unusually large number of filaments per plica is more reminiscent of homorhabdic eulamellibranch gills. The general form of the gill is similar to that described in some other pteriomorphs, most specifically Pteria. However, it has more complex junctions and interconnections, although these are not as intricate or pervasive as those observed in the pseudolamellibranch Ostreidae. The connections and well-developed filament framework allowed the gill to reach its unusually large size, supporting the large size of these inoceramid species. The unusually large size of the gill and its components indicate that the organism fed on the larger suspended organic particles in the water column. It would also have been capable of processing large volumes of water quickly, leading to greater potential for food accumulation and with likely implications for respiratory efficiency. This may help explain the common association of inoceramids with oxygen-deficient palaeoenvironments, particularly as the general structure of the inoceramid gill is very different to that observed in the commonest extant chemosymbiotic bivalves. [ABSTRACT FROM AUTHOR]

Intrinsic birefringences of polycaprolactone filaments are determined using the approach suggested by Samuels. First, intrinsic lateral moduli are determined from the values of crystallinity and sonic moduli of unoriented filaments. These values are found to be 3.473 GPa and 0.071 GPa, respectively, for crystalline and amorphous regions. The crystallinity, sonic moduli and crystalline orientation function of drawn and heat set filaments are used to evaluate amorphous orientation functions. Finally, Stein and Norris's equation along with birefringence data is used to obtain intrinsic birefringence values of crystalline and amorphous regions and these values are found to be 0.079 ± 0.002 for crystalline regions and 0.066 ± 0.008 for amorphous regions. Copyright © 2012 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Abstract: FadA, a novel adhesin of periodontal pathogen Fusobacterium nucleatum is composed of two forms, pre-FadA and mature FadA (mFadA), constituting the functional FadA complex (FadAc). By electron microscopy, we observed that mFadA formed uniformly long and thin filaments, while FadAc formed heterogeneous filaments of varying lengths and widths, as well as “knots”. Mutants in signal peptide or in the non-alpha-helical loop retaining heterogeneous structures had binding activity while those forming aggregates or long filaments lost activity. These observations suggest short filaments and knots may be the active forms of FadA. This is the first demonstration that a signal peptide is required for the assembly of a bacterial adhesin. Structured summary of protein interactions: mFadA and pre-FadA interaction by transmission electron microscopy (View interaction) [Copyright &y& Elsevier]

Abstract: We describe the purification, crystallization and structure for the GTP-binding domain of human septin 7 (SEPT7G). We show that it forms filaments within the crystal lattice which employ both the G and NC interfaces, similar to those seen in the hetero-filament of SEPT2/6/7. The NC interface is considered promiscuous as it is absent from the hetero-filament. Such promiscuity could provide the potential for permuting monomers along a filament in order to generate diversity in hetero-polymers. On the other hand, our results suggest that the G and NC interfaces may be necessary but insufficient for determining correct hetero-filament assembly. Structured summary of protein interactions: SEPT7G and SEPT7G bind by X-ray crystallography (View interaction). SEPT7 G and SEPT7 G bind by molecular sieving (View interaction). [Copyright &y& Elsevier]

The aim of this paper is the preparation and characterization of cellulosechitin blend filaments over the experimental blend ratio scope i.e., 2.89 and 6.46 ww chitin content through high wet modulus HWM procedure. The spinnability of the invested solutions was found to vary in the following order: chitin < cellulose < 9.5:0.5 blend < 9:1 blend < 8:2 blend < 5:5 blend 9:1 means the mass ratio of cellulose to chitin, so does 9.5:0.5, 8:2, and 5:5. The crosssection of the blend filaments is of chrysanthemum shape. It was shown through the SEM photographs that there existed grooves on the surface of filaments, which became coarse with increase in chitin content. Based on the data from Xray, sonic velocity, intensity, and hygroscopicity, it is concluded that the degree of crystallinity, dry and wet intensity modulus, degree of orientation, and regain rate of the filaments decreased with increase in chitin content in the experiment scope. The mechanical properties of the blend filaments are much higher than those of Crabyon fiber and normal viscose filaments, which proves that the HWM method is an efficient way of preparing cellulosechitin blend filaments with satisfactory mechanical properties and processing property. The blend filaments prepared have an effective biostatic effect on Staphylococcus aureus, Escherchia coli, and Corinebaterium michiganenceaccording to different testing standards. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The distant phylogenetic position of brown macroalgae from the other multicellular phyla offers the opportunity to study novel and alternative developmental processes involved in the establishment of multicellularity. At present, however, very little information is available about developmental patterning in this group. Ectocarpus siliculosus (Dillwyn) Lyngb. has uniseriate filaments and displays one of the simplest architectures in the Phaeophyceae. The aim of this study was to decipher the morphogenetic steps that lead to the development of the Ectocarpus sporophyte. We carried out a detailed morphometric study of the events that occurred between gamete germination and the 100-cell stage. This analysis was performed on two ecologically distant isolates to assess plasticity in developmental patterning within this species. Cell sizes were measured in both isolates, allowing the definition of two main cell types based on their shape (round and elongated). On average, the filament is composed of about 40% round cells, which are present in the central region of the filament, but different combinations of the two cell types within filaments were observed and quantified. Young sporophytes grew apically, with elongated cells progressively differentiating into round cells. Secondary filaments emerged preferentially on round cells, primarily from the older central cells. Statistical analyses showed that the pattern of branching was regulated to ensure a stereotyped architecture. This description of the developmental patterning during the growth of the E. siliculosus sporophyte will serve as a base for more detailed studies of development, in this species and in brown algae in general. [ABSTRACT FROM AUTHOR]

Sarcomeric filament proteins display extraordinary properties in terms of protein length and mechanical elasticity, requiring specific anchoring and assembly mechanisms. To establish the molecular basis of terminal filament assembly, we have selected the sarcomeric M-band protein myomesin as a prototypic filament model. The crystal structure of the myomesin C-terminus, comprising a tandem array of two immunoglobulin (Ig) domains My12 and My13, reveals a dimeric end-to-end filament of 14.3 nm length. Although the two domains share the same fold, an unexpected rearrangement of one β-strand reveals how they are evolved into unrelated functions, terminal filament assembly (My13) and filament propagation (My12). The two domains are connected by a six-turn α-helix, of which two turns are void of any interactions with other protein parts. Thus, the overall structure of the assembled myomesin C-terminus resembles a three-body beads-on-the-string model with potentially elastic properties. We predict that the found My12-helix-My13 domain topology may provide a structural template for the filament architecture of the entire C-terminal Ig domain array My9–My13 of myomesin. [ABSTRACT FROM AUTHOR]

Since their essential role in cytokinesis was first shown in yeast, the septins have been described to function in diverse cellular contexts. The members of this unique class of GTPases are capable of binding and hydrolyzing GTP, associating with membranes and oligomerizing into higher order structures. Here we describe Sept12, a novel septin, identified in a yeast two hybrid screen using Sept5 as the bait. Sept12 contains the primary sequence elements of a septin and is capable of interacting with other septins. In addition, Sept12 purifies with bound nucleotide and binds to phosphoinositides, confirming its identity as a septin. RT-PCR and Northern blots reveal that Sept12 mRNA is expressed predominantly in testis, and this is supported by tissue Western blots. In rats, Sept12 protein levels rise upon sexual maturity and the Sept12 protein colocalizes with the annulus in isolated mature spermatozoa. Further, coexpression of Sept12 with Sept4, an essential annulus component, results in complete colocalization of both proteins into robust and highly curved filaments in CHO cells. This study suggests Sept12 may be involved in mammalian fertility. Cell Motil. Cytoskeleton 2007. © 2007 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

The septins constitute a family of GTPase proteins that are involved in many cytological processes such as cytokinesis and exocytosis. Previous studies have indicated that mammalian Sept3 is a brain-specific protein that is abundant in synaptic terminals. Here, we further investigated the localization and function of Sept3 in the mouse brain. Sept3 is expressed in several types of post-mitotic neurons, including granule cells in the cerebellum and pyramidal neurons in the cerebral cortex and hippocampus. In primary cultures of hippocampal pyramidal neurons, Sept3 protein is enriched at the tips of growing neurites during differentiation. Sept3 directly binds to Sept5 and Sept7 and forms a heteromeric complex at nerve terminals adjacent to where a synaptic vesicle marker, synaptophysin, is expressed in mature neurons. When over-expressed in HEK293 cells, Sept3 forms filamentous structures that are dependent on the presence of its GTP- and phosphoinositide-binding domains. To investigate the physiological roles of Sept3, we generated Sept3 deficient mice. These mice show no apparent abnormalities in histogenesis nor neuronal differentiation in culture. Expression of synaptic proteins and other septins are unaltered, indicating that Sept3 is dispensable for normal neuronal development. [ABSTRACT FROM AUTHOR]

Actin participates in many important biological processes. Currently, intensive investigation is being carried out in a number of laboratories concerning the function of actin in these processes and the molecular basis of its functions. We present a glimpse into four of these areas: actin-like proteins in bacterial cells, actin in the eukaryotic nucleus, the conformational plasticity of the actin filament, and finally, Arp2/3-dependent regulation of actin filament branching and creation of new filament barbed ends. IUBMB Life , 57: 683–687, 2005 [ABSTRACT FROM AUTHOR]

Escherichia coli SeqA binds clusters of transiently hemimethylated GATC sequences and sequesters the origin of replication, oriC, from methylation and premature reinitiation. Besides oriC, SeqA binds and organizes newly synthesized DNA at replication forks. Binding to multiple GATC sites is crucial for the formation of stable SeqA–DNA complexes. Here we report the crystal structure of the oligomerization domain of SeqA (SeqA–N). The structural unit of SeqA–N is a dimer, which oligomerizes to form a filament. Mutations that disrupt filament formation lead to asynchronous DNA replication, but the resulting SeqA dimer can still bind two GATC sites separated from 5 to 34 base pairs. Truncation of the linker between the oligomerization and DNA-binding domains restricts SeqA to bind two GATC sites separated by one or two full turns. We propose a model of a SeqA filament interacting with multiple GATC sites that accounts for both origin sequestration and chromosome organization. [ABSTRACT FROM AUTHOR]

Auxin response factors (ARFs) play a central role in plants as transcriptional factors in response to auxin. TheArabidopsis ARF8gene is a light-inducible gene and ARF8 protein might control auxin homeostasis in a negative feed-back fashion through regulation ofGH3gene expression. In a double mutant designated infertile line includingarf8-1(a T-DNA insertion mutantof ARF8), weisolated fertility1-1 (fer1-1), a mutant ofFer1, which acts synergistically withARF8to control the development of the anther and filament inArabidopsis.Genetics analysis has demonstrated thatfer 1-1is a T-DNA insertion line, indicating thatFer1might be cloned by inverse polymerase chain reaction (PCR) or the TAIL-PCR approach. Phenotypic identification and molecular analysis offer 1-1and the infertile line will be helpful to characterize the function ofFer1, to further study the function ofARF8, and to reveal the molecular mechanism underlying the interaction ofFer1andARF8in controlling development of the anther and filament.(Managing editor: Li-Hui ZHAO) [ABSTRACT FROM AUTHOR]

The relationship between anther dehiscence and dehydration of the filament tip and the connective tissue were followed in Gasteria verrucosa (Mill) H. Duval, Allium cepa L. and Lilium hybrida cv. 'Enchantment' using various microscopical techniques, including direct observations of living tissues in the SEM. In G. verrucosa anther dehiscence immediately follows anthesis, with concomitant dehydration and shrivelling of the filament tip. In L. hybrida the filament tip dehydrates and shrivels before anthesis, The anthers start to dehisce immediately after anthesis. In A. cepa the filament tip dehydrates and shrivels slowly after anthesis and dehiscence, which may take up to several days, correlates with the rate of extension of the filament. The attenuated period of dehiscence in A. cepa may be related to the absence of stomata on the anther. Experiments on xylem conductivity and transpiration reveal that the presence of continuously open stomata on the anthers sets the time of dehiscence after anthesis in G. verrucosa and L. hybrida. The shrinking filament tip in all three species functions as a hinge which suspends the dangling anther after dehiscence. The uniformly thickened epidermal cell walls on the anthers opposite the filament prevent the outwardly bending locule walls from embracing the filament. [ABSTRACT FROM AUTHOR]

The polymerization of actin induced by dilution has previously been reported, where a 1000-fold molar excess of ATP over actin resulted when actin was diluted to 4.0 microg/ml in low salt buffer A (0.1 mM ATP, 0.1 mM CaCl[sub 2], 2 mM Tris-HCl, pH 8.0, 5 mM 2- mercaptoethanol, 1 mM NaN[sub 3]). Filaments formed by the addition of ATP to a 1000-fold molar excess over actin in buffer B (0.1 mM CaCl[sub 2], 2 mM Tris-HCl, pH 8.0, 1 mM NaN[sub 3]) were then separated by gel-filtration. When ATP was removed from these filaments using Dowex-1, depolymerization occurred. Thus, the reversible polymerization induced by the dilution of actin or by addition of ATP can be ascribed to the binding of ATP at the low affinity site of actin. [ABSTRACT FROM AUTHOR]

The filamentous spirally coiled cyanoprokaryote Arthrospira fusiformis is found in extremely high densities in tropical soda lakes acting as driving force of the food web. We studied pronounced temporal morphological changes of Arthrospira in Kenyan soda lakes, Nakuru and Bogoria, and identified underlying key factors. Cell (diameter and height) and filament (height of coil, coil diameter, and number) dimensions were measured from weekly samples collected over a period of 16 months. In both lakes, medium-sized cells and large, widely coiled filaments prevailed most. Percentage of large, widely coiled filaments was promoted by elevated levels of soluble reactive phosphorus, wind speed, temperature and conductivity and the opposite for small filaments. Large, narrow-coiled filaments were associated with an increase in mainly Arthrospira-grazing zooplankton and cyanophage infections. Widely coiled spirals were promoted by increased turbulences. Based on fluorescence measurements, we found widely coiled filaments representing high vitality. From this study we were able to demonstrate for the first time morphological patterns of Arthrospira in nature. Arthrospira morphotypes are suitable for indicating the biological status in soda lakes as they are subjective and therefore reflective of what is happening in its habitat. Additionally, this outcome might be also of interest for commercial 'Spirulina' farms in enhancing high-quality production., (© 2013 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.)