Tubular Crystals Research Articles

Non-Classical Euler Buckling and Brazier Instability in Cylindrical Liquid Droplets.

Crystalline monolayers prevalent in nature and technology possess elusive elastic properties with important implications in fundamental physics, biology, and nanotechnology. Leveraging the recently discovered shape transitions of oil-in-water emulsion droplets, upon which these droplets adopt cylindrical shapes and elongate, we investigate the elastic characteristics of the crystalline monolayers covering their interfaces. To unravel the conditions governing Euler buckling and Brazier kink formation in these cylindrical tubular interfacial crystals, we strain the elongating cylindrical droplets within confining microfluidic wells. Our experiments unveil a nonclassical relation between the Young's modulus and the bending modulus of these crystals. Intriguingly, this relation varies with the radius of the cylindrical crystal, presenting a nonclassical mechanism for tuning of elasticity in nanotechnology applications.

#1760 Four cases of ADTKD: AFM analysis of urine sediment

Abstract Background and Aims Autosomal Dominant Tubulointerstitial kidney disease (ADTKD) is a rare disease (16 per million), associated with CV events, hypertension, and gout. ADTKD is characterized by interstitial fibrosis, tubular atrophy, microcysts, and progressive CKD. We describe a case of a family with clinical characteristics of ADTKD and provide for the first time a characterization of their urinary sediment. Given the tendency of a specific type of ADTKD caused by UMOD mutation to form tubular crystals, we have also tested the ability of the urine from ADTKD patients to precipitate and form crystals in vitro. Method We examined clinical features and urinary sediment of a family with ADTKD: a 51 years old woman with CKD (eGFR 30 mL/min/1.73 m2, CDK-EPI 2021) and her three sons, a 20 years old male, two daughters of 26 and 24 years old, all with hyperuricemia. Genetic analysis is not yet available. The test of urine precipitation consisted of the analysis of crystals after air-drying a thin layer of urine after enrichment of the organic quota by triple centrifugation for 10 minutes at 1000 rpm. Urinary sediments were also studied by Atomic Force Microscopy (ICSPI nGauge AFM) to achieve a resolution of 20 nm of crystals. Results Clinical data for the four patients are reported in the table. None of the patients showed proteinuria. The urine sediment of all patients showed rare WBC (in greater amounts only in patient 1), rare amorphous granular casts, and rare tubular cells. Three patients showed formations of variably sized crystals in vitro. The precipitation test did not show crystals in patient 1, whereas patients 2-3 showed several rosette-type crystals often with a wagon-wheel concentric contour which resembled leucine crystals or CaCO3. Adding formalin to the samples resulted in a more clear organization of crystals in wagon-wheel structures. AFM imaging of the crystals showed rod-like structures branching with an angle of 35°. Conclusion ADTKD remains a poorly understood genetic condition with no specific treatment options. Our data suggest that patients with this condition may have an enhanced tendency to form crystals in vitro. Speculatively, this might induce tubular injury in vivo. Data from UMOD-ko animal models showed intrarenal crystals (not better specified). Genetic alterations of branched aminoacids metabolism (such as leucine in Maple syrup disease) can also cause tubular diseases, although the systemic manifestations are very different from our patients. Genetic analysis of our family will give further information on the proteins involved in these crystal structures.

Micromorphological and Chemical Characterization of Drimys winteri Leaf Surfaces: The Secondary Alcohols Forming Epicuticular Wax Crystals Are Accompanied by Alkanediol, Alkanetriol and Ketol Derivatives.

The cuticle is a hydrophobic coating of most aerial plant surfaces crucial for limiting non-stomatal water loss. Plant cuticles consist of the lipid polyester cutin and associated waxes with compositions varying widely between plant species and organs. Here, we aimed to provide a comparative analysis of the dark-glossy adaxial and pale-glaucous abaxial sides of Drimys winteri (Winteraceae) leaves. Scanning electron microscopy showed nanotubular wax crystals lining the entire abaxial side of the leaf (including stomatal pores), while the adaxial side had patches of mixed platelet/tubule crystals and smooth areas between them. Consecutive treatments for wax removal and cutin depolymerization revealed that the waxes were deposited on a cutin network with micron-scale cavities across the entire abaxial surface including the stomata pores, and on a microscopically smooth cutin surface on the adaxial side of the leaf. Gas chromatography coupled to mass spectrometry and flame ionization detection showed that the wax mixtures on both sides of the leaf were complex mixtures of very-long-chain compounds dominated by the secondary alcohol nonacosan-10-ol and alkanediols with one hydroxyl on C-10. It is therefore very likely that the characteristic tubular wax crystals of both leaf sides are formed by these alcohols and diols. Further secondary alcohols and alkanediols, as well as ketols and alkanetriols with one functional group on C-10, were identified based on mass spectral fragmentation patterns. The similarities between all these mid-chain-functionalized compounds suggest that they are derived from nonacosan-10-ol via regio-specific hydroxylation reactions, likely catalyzed by three P450-dependent monooxygenases with different regio-specificities.

Sequences of dislocation reactions and helicity transformations in tubular crystals

Sequences of dislocation reactions and helicity transformations in tubular crystals

Influence of multi-walled carbon nanotubes/N, N-dimethylformamide slurry amount on fouling release performance of silicone coatings

MWCNTs reinforced silicone coatings were prepared by mechanically mixing hydroxyl-capped polydimethylsiloxane (PDMS) and multi-walled carbon nanotubes/N, N-dimethylformamide (MWCNTs/DMF) slurries. The effects of MWCNTs/DMF slurry amount on the fouling release performance of silicone coatings were investigated. Incorporation of 5 wt% MWCNTs/DMF slurry increased the elongation and reduced Young's modulus, Shore's hardness, and roughness observed. As a result, an excellent silicone coating was fabricated with stable surface properties, fouling release performance, economic savings, and prolonged longevity for marine applications. Silicone coatings reinforced by MWCNTs were prepared by mechanical blending. MWCNTs are tubular crystals 30–80 nm in diameter and less than 10 μm long. The effects of MWCNTs/DMF slurry amount on the coating properties were investigated by dispersion properties, surface properties, mechanical properties, marine bacteria adhesion, and Navicula tenera adhesion test. The most favorable fouling release performance with the lowest roughness (0.168 ± 0.008 μm), the minimum Shore's hardness (18.47 HA), and the minimum relative adhesion factor (5.88 RAF) were shown for the silicone coatings prepared with 5 wt% MWCNTs/DMF slurry.

Bowl-Shaped Bispyrrole-Fused Perylene-diimide and Its Anions.

Incorporating two pyrrole subunits at the bay positions of perylene-diimide has been a long-pursued goal since 2009, but it has not been achieved due to high strain. Herein, via one step Buchwald-Hartwig reaction, PDI-2N was successfully generated with a bowl depth of 1.52 Å. Though with electron-rich pyrrole embedding, PDI-2N's radical anion and dianion were facilely prepared and were investigated both experimentally and theoretically. Moreover, PDI-2N crystallized in different manners under distinct conditions, and it formed tubular crystals with infinite two-directional columnar stacking under DMF conditions. This finding develops a dream bowl-shaped PDI derivative that holds great promise in organoelectronics.

Technology and Thermomechanics in Growing Tubular Silicon Single Crystals

Technology and Thermomechanics in Growing Tubular Silicon Single Crystals

3D bioprinted in vitro secondary hyperoxaluria model by mimicking intestinal-oxalate-malabsorption-related kidney stone disease

Secondary hyperoxaluria (SH) is a multifactorial disorder that extends from inflamed intestinal epithelium with oxalate malabsorption to kidney stone disease; its prevalence is increasing annually. Studying complex SH has been a considerable challenge because of the lack of an in vitro multiorgan model that describes dynamic pathophysiological interactions between the native intestinal epithelium and proximal tubule (PT). An in vitro multiorgan model is developed using a multi-biofabrication technique to address this challenge; this developed microfluidic in vitro multiorgan model demonstrates the enhanced functional interconnection between the intestinal epithelium and a vascularized PT by printing compartmentalized two organs close together. This spatially organized multiorgan model with enhanced fluidic connectivity provides a tool for recapitulating the critical pathophysiological features of SH, which includes intestinal barrier disruption, calcium oxalate (CaOx) crystallization, and crystal-induced PT injuries. The biophysical properties (e.g., glucose reabsorption and tubular fluid flow behavior-dependent CaOx crystal formation) of an in vitro SH model are thoroughly analyzed by comparison with the pathophysiology of human PT. Further, the efficiency of the in vitro 3D model as a drug testing platform is validated by assessing CaOx crystal dissolution on perfusing the device with trisodium citrate and grape seed extract. With no U.S. Food and Drug Administration (FDA)-approved SH therapeutics, this optimized in vitro SH model can be actively utilized as a promising platform for discovering integrative therapeutics to reverse intestinal epithelial inflammation and recurrent kidney stone disease in a single assay.

Incubation in Michel Transport Medium as a Diagnostic Tool to Differentiate Between Calcium Oxalate and 2,8-Dihydroxyadenine Tubular Crystals in a Kidney Biopsy

Incubation in Michel Transport Medium as a Diagnostic Tool to Differentiate Between Calcium Oxalate and 2,8-Dihydroxyadenine Tubular Crystals in a Kidney Biopsy

New approaches for the study of faience using beads from Southern Portugal

A collection of 30 faience beads recovered from the Iron Age necropolis of Vinha das Caliças 4 (Beja, Portugal) was analyzed in order to identify their production technology and provide insights into their possible provenance. The multi-analytical approach employed, combining laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), variable pressure scanning electron microscope coupled with energy dispersive X-ray spectrometry (VP-SEM-EDS) and micro-X-ray diffraction (µ-XRD), highlights the difficulties that arise from the analysis of weathered faience objects, and which are augmented by their intrinsic heterogeneous nature.VP-SEM-EDS analysis and LA-ICP-MS mapping revealed that the disk-shaped faience beads were manufactured using the cementation glazing method. Copper, most likely in the form of bronze scrapings, was used to impart a blue-green hue to these beads. Micro-XRD also revealed that the disk-shaped beads were manufactured using feldspathic sand. On the other hand, the cubic-shaped bead, identified as an Egyptian blue frit by VP-SEM-EDS and μ-XRD, owes its vivid blue color to the tubular crystals of this well-known synthetic pigment.Trace element analysis suggests that all beads were manufactured in the Levant region using coastal sands.Ultimately, this study highlighted the importance of the use of a combination of microstructural and geochemical criteria in the identification of faience production technology and provenance. The importance of the selection of the sampling strategy in LA-ICP-MS analysis of weathered faience objects was also emphasized.

Technology and thermomechanics in growing tubular silicon single crystals

The problem of growing high-resistance low-dislocation tubular silicon single crystals for non-planar manufacturing technologies of epitaxial p-n junctions and the production of new-generation power semiconductor devices is considered. The possibilities of Stepanov method for growing volumetric profiled crystalline products, the application of which is based on the use of shapers of various designs, are discussed. In particular, the shortcomings of shapers associated with the melt contamination by foreign particles and impurities are discussed. Therefore, the main attention is paid to the use of equipment that implements crystal growth from a melt without a shaper by Czochralski method. The processes of thermal mechanics are preliminary analyzed in relation to the existing and well-established process of growing polycrystalline highly dislocation silicon pipes of large diameter by Czochralski method for epitaxial reactors.It is noted that the growth of tubular low-dislocation small diameter silicon single crystals requires a significant modernization of the standard hot zone, which in this work is implemented for “REDMET-10” Czochralski furnace. By means of computer simulation, thermal mechanical processes are calculated for such a modernized Czochralski furnace. The parameters of grown tubular silicon single crystals are characterized, and their manufacturing suitability for power semiconductor devices using nonplanar technology is assessed.

Synthesis, characterization, visualization, and growth mechanism of macro-sized tubular MgO crystals formed in situ from refractory magnesia with aluminum

MgO crystals are widely used in many industries for resisting thermal and corrosion resistance. Macro-sized tubular MgO crystals with porous structures were successfully synthesized via the compaction of magnesia and aluminum powder at temperatures above 1400 °C in an air atmosphere. The morphology and densification of the MgO tube could be easily controlled by the shape of the bore on the Al2O3 lid and the heat treatment temperature. The bore of the Al2O3 crucible was critical for MgO tube growth. The thermite reaction produced a large amount of Mg vapor, and the oxygen in the crucible was squeezed out through the bore. Owing to the constraint of the air atmosphere, the MgO vapor flowing out of the crucible, which is generated by the oxidation of the Mg vapor, is preferentially deposited around the bore to form a MgO wall. Macro-sized tubular MgO crystals were obtained by MgO wall growth. A high-temperature visualization system based on monochromatic light was applied to observe the MgO tube growth process, and the growth mechanism was confirmed. These findings can be expected to enhance the aluminum-containing magnesia-based refractories with self-healing and presents a promising strategy for the economical production of high-purity MgO.

Light Chain Restriction in Proximal Tubules-Implications for Light Chain Proximal Tubulopathy.

Monoclonal gammopathy (MG) causes various nephropathies, which may suffice for cytoreductive therapy even in the absence of diagnostic criteria for multiple myeloma or B-cell non-Hodgkin lymphoma. The aim of this study was to better understand the significance of light chain (LC) restriction or crystals (LC-R/C) in proximal tubules in the spectrum of LC-induced nephropathies. A consecutive cohort of 320 renal specimens with a history of B-cell dyscrasia was characterized. Special attention was paid to immunohistochemical LC restriction in proximal tubules, tubular crystals or constipation, and ultrastructural findings. Complementary cell culture experiments were performed to assess the role of LC concentrations in generating LC restriction. Light chain restriction or crystals in proximal tubules was found in a quarter of analyzed cases (81/316) and was associated with another LC-induced disease in 70.4% (57/81), especially LC cast-nephropathy (cast-NP) and interstitial myeloma infiltration. LC restriction without significant signs of acute tubular injury was observed in 11.1% (9/81). LC-R/C was not associated with inferior renal function compared to the remainder of cases, when cases with accompanying cast-NP were excluded. Besides crystals, cloudy lysosomes were significantly associated with LC-R/C on an ultrastructural level. In summary, LC-R/C is frequent and strongly associated with cast-NP, possibly indicating that a high load of clonal LC is responsible for this phenomenon, supported by the observation that LC restriction can artificially be generated in cell culture. This and the lack of significant tubular injury in a subgroup imply that in part LC-R/C is a tubular trafficking phenomenon rather than an independent disease process.

Shape multistability in flexible tubular crystals through interactions of mobile dislocations

We study avenues to shape multistability and shape morphing in flexible crystalline membranes of cylindrical topology, enabled by glide mobility of dislocations. Using computational modeling, we obtain states of mechanical equilibrium presenting a wide variety of tubular crystal deformation geometries, due to an interplay of effective defect interactions with out-of-tangent-plane deformations that reorient the tube axis. Importantly, this interplay often stabilizes defect configurations quite distinct from those predicted for a two-dimensional crystal confined to the surface of a rigid cylinder. We find that relative and absolute stability of competing states depend strongly on control parameters such as bending rigidity, applied stress, and spontaneous curvature. Using stable dislocation pair arrangements as building blocks, we demonstrate that targeted macroscopic three-dimensional conformations of thin crystalline tubes can be programmed by imposing certain sparse patterns of defects. Our findings reveal a broad design space for controllable and reconfigurable colloidal tube geometries, with potential relevance also to architected carbon nanotubes and microtubules.

Orientational isomerisation of guest molecules in equilibrium in a tubular host crystal formed via halogen and hydrogen bonding

The orientation of the guest molecules in the one-dimensional tube is reversed in a temperature-dependent manner, and the ratio of the two orientational isomers changes continuously and reversibly from 100 : 0 to 0 : 100 in thermodynamic equilibrium.

The role of chirality and plastic crystallinity in the optical and mechanical properties of chlorosomes

SummaryThe most efficient light-harvesting antennae found in nature, chlorosomes, are molecular tubular aggregates (TMAs) assembled by pigments without protein scaffolds. Here, we discuss a classification of chlorosomes as a unique tubular plastic crystal and we attribute the robust energy transfer in chlorosomes to this unique nature. To systematically study the role of supramolecular tube chirality by molecular simulation, a role that has remained unresolved, we share a protocol for generating realistic tubes at atomic resolution. We find that both the optical and the mechanical behavior are strongly dependent on chirality. The optical-chirality relation enables a direct interpretation of experimental spectra in terms of overall tube chirality. The mechanical response shows that the overall chirality regulates the hardness of the tube and provides a new characteristic for relating chlorosomes to distinct chirality. Our protocol also applies to other TMA systems and will inspire other systematic studies beyond lattice models.

Tubular phononic crystal sensor

We propose the design of a tubular phononic crystal (TPC) for the purpose of sensing the physical properties of a liquid filling the hollow part of the tube. The TPC is constituted by a periodic repetition of washers along a hollow pipe with the advantage of avoiding any perturbation of a flowing fluid by any element inside the tube. Using finite element simulations, we demonstrate the existence of complete as well as polarization dependent bandgaps inside which one can design localized modes associated with defects. The most sensitive cavity to the liquid sound velocity is found to be constituted by a Fabry–Pérot (F–P) cavity. The signature of the cavity modes can be detected as peaks or dips in the transmission spectrum as well as at the external surface of the cavity. We study the dramatic effect of the liquid viscosity, more particularly shear viscosity, on these features and discuss the conditions for their practical observation. A TPC test sample made of a polymer is fabricated by means of 3D printing and characterized without the liquid by transmission measurements. The comparison with the simulations showed the necessity of considering the damping of the polymer whose effect on the transmission features is discussed. Our sensor design can find many applications at different scales in several systems transporting a fluid as microfluidic channels in micro- and nanotechnologies, syringes in medicine, or pipelines in civil engineering.

Zinc binding alters the conformational dynamics and drives the transport cycle of the cation diffusion facilitator YiiP.

YiiP is a secondary transporter that couples Zn2+ transport to the proton motive force. Structural studies of YiiP from prokaryotes and Znt8 from humans have revealed three different Zn2+ sites and a conserved homodimeric architecture. These structures define the inward-facing and outward-facing states that characterize the archetypal alternating access mechanism of transport. To study the effects of Zn2+ binding on the conformational transition, we use cryo-EM together with molecular dynamics simulation to compare structures of YiiP from Shewanella oneidensis in the presence and absence of Zn2+. To enable single-particle cryo-EM, we used a phage-display library to develop a Fab antibody fragment with high affinity for YiiP, thus producing a YiiP/Fab complex. To perform MD simulations, we developed a nonbonded dummy model for Zn2+ and validated its performance with known Zn2+-binding proteins. Using these tools, we find that, in the presence of Zn2+, YiiP adopts an inward-facing conformation consistent with that previously seen in tubular crystals. After removal of Zn2+ with high-affinity chelators, YiiP exhibits enhanced flexibility and adopts a novel conformation that appears to be intermediate between inward-facing and outward-facing states. This conformation involves closure of a hydrophobic gate that has been postulated to control access to the primary transport site. Comparison of several independent cryo-EM maps suggests that the transition from the inward-facing state is controlled by occupancy of a secondary Zn2+ site at the cytoplasmic membrane interface. This work enhances our understanding of individual Zn2+ binding sites and their role in the conformational dynamics that govern the transport cycle.

A facile solution synthesis of scaly-like hollow SnSe nanotubes for self-powered infrared sensor

SnSe nanotubes (NTs) have been successfully synthesized via a simple solution method. The as-synthesized tubular crystals with orthorhombic structure are composed of numerous scaly nanosheets which distributed hierarchically. The average diameter of the SnSe NTs is roughly 180 nm and length primarily concentrate in the range of 1–3 µm. It was found that Se nanowires were served as a template and as an only source of Se ion for the formation of SnSe NTs. Furthermore, a novel self-powered infrared photodetector (IRPD) established on the SnSe NTs with desirable detection performance was fabricated. Exposed to IR illumination of 830 nm, the SnSe NTs IRPD displays a maximal photocurrent density of 46.46 nA/cm2 and a rapid photoresponse, together with the rise time and decay time approach up to 0.174 s and 0.349 s, respectively. Meanwhile, it can be recognized that the SnSe NTs IRPD remain consistent and repeatable at zero voltage. Moreover, a plausible mechanism for IR detection based on the SnSe NTs IRPD are also discussed.

FEATURES OF THE FORMATION OF THE STRUCTURE OF A CEMENTLESS MATRIX COMPOSITE BASED ON MECHANICALLY ACTIVATED TECHNOGENIC RAW MATERIALS

The creation of composite materials using mechanically activated technogenic raw materials is relevant today as part of a large-scale task of construction and technological utilization of technogenic formations. The change in the crystal structure using mechanochemistry increases the activity of technogenic products: the number of coagulation contacts of dissimilar particles increases, increases the plastic strength of the hardening mixture, formation of hydration products is accelerated. The article is devoted to the study of the mechanism of structural and rheological transformations of a cementless hardening system based on activated steelmaking. Steel melting slags were used as raw materials - energy-saturated large-capacity waste of the West-Siberian Metallurgical Combine (Novokuznetsk). As components - activators - waste from the coal industry of the «Abashevskaya» mine (Novokuznetsk) - burnt rocks with heaps and slimes, obtained by neutralization of spent acid battery electrolytes with lime batteries for industrial vehicles. Based on used mechanically activated technogenic raw materials the binder composite material of the matrix structure is obtained. To assess structural and material changes in the hardening system comprehensive physical and chemical studies were carried out: IR - spectroscopy, thermogravimetric and x-ray phase analysis. Electron microscopy investigated the structure of the stone. It was found that the matrix structure of the composite material is a dispersion medium - matrix of dense fine-grained masses calcium sulfate hydrate; dispersed phase from lamellar crystals of quartz and magnesium oxide, and tubular crystals of calcium orthosilicate; and transitional interfacial layer from structured grains of calcium hydrosulfoaluminate. In the process of forming the structure interdependence of phases from each other was accompanied by a sequential transition of some types of structures to others: coagulation→ crystallization- condensation→ crystallization. The article presents the results of the self-organization of the structure, the interaction of oxide systems in the process of hydration is considered, major mineral neoplasms are established, possessing astringent properties and providing strong bonds between structure-forming components.