Morphology Aspect Research Articles

Effect of Cubic Crystal Morphology on Thermal Characteristics and Mechanical Sensitivity of PYX

To investigate the influence of the cubic crystal morphology on the thermal properties and sensitivity of 2,6-bis(picrylamino)-3,5-dinitropyridine (PYX), cubic PYX (CPYX) crystals were prepared using the antisolvent method. Scanning electron microscopy (SEM), laser particle size analysis, X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR) were used to characterize the morphology, particle size and structure of the prepared products. The thermal behavior, thermal decomposition kinetics, thermal safety parameters and thermal decomposition mechanism of CPYX were investigated by differential scanning calorimetry–thermogravimetry–mass spectrometry–Fourier transform infrared spectrometry (DSC-TG-MS-FT-IR) and in situ FT-IR experiments. Meanwhile, the mechanical sensitivity of CPYX was determined by means of the explosion probability method. The results showed that the product had a smooth cubic morphology and small crystal aspect ratio with an average particle size (d50) of 10.65 μm, but it had no distinct differences from the crystal structure of raw PYX (RPYX). The thermal decomposition peak temperature, the self-accelerating decomposition temperature and the critical temperature of the thermal explosion of CPYX increased by 7.2 °C, 6.1 °C and 10.4 °C, respectively, compared to RPYX. Similarly, the apparent activation energy increased by 15%. Besides these, the impact sensitivity and friction sensitivity of CPYX decreased by 36% and 20%, respectively, compared to RPYX. The decomposition process of CPYX contains two stages. The first stage involves the breakage of N-H bonds and -NO2 groups with the release of CO2, N2O, NO, HCN and H2O, followed by the thermal decomposition of the resulting intermediate and the release of CO2, N2O and HCN in the second stage.

Collagen and Alginate Hydrogels Support Chondrocytes Redifferentiation In Vitro without Supplementation of Exogenous Growth Factors.

Focal cartilage defects are a prevalent knee problem affecting people of all ages. Articular cartilage (AC) possesses limited healing potential, and osteochondral defects can lead to pain and long-term complications such as osteoarthritis. Autologous chondrocyte implantation (ACI) has been a successful surgical approach for repairing osteochondral defects over the past two decades. However, a major drawback of ACI is the dedifferentiation of chondrocytes during their in vitro expansion. In this study, we isolated ovine chondrocytes and cultured them in a two-dimensional environment for ACI procedures. We hypothesized that 3D scaffolds would support the cells' redifferentiation without the need for growth factors so we encapsulated them into soft collagen and alginate (col/alg) hydrogels. Chondrocytes embedded into the hydrogels were viable and proliferated. After 7 days, they regained their original rounded morphology (aspect ratio 1.08) and started to aggregate. Gene expression studies showed an upregulation of COL2A1, FOXO3A, FOXO1, ACAN, and COL6A1 (37, 1.13, 22, 1123, and 1.08-fold change expression, respectively) as early as day one. At 21 days, chondrocytes had extensively colonized the hydrogel, forming large cell clusters. They started to replace the degrading scaffold by depositing collagen II and aggrecan, but with limited collagen type I deposition. This approach allows us to overcome the limitations of current approaches such as the dedifferentiation occurring in 2D in vitro expansion and the necrotic formation in spheroids. Further studies are warranted to assess long-term ECM deposition and integration with native cartilage. Though limitations exist, this study suggests a promising avenue for cartilage repair with col/alg hydrogel scaffolds.

High-performance Ni-based superalloy 718 fabricated via arc plasma directed energy deposition: effect of post-deposition heat treatments on microstructure and mechanical properties

Ni-based superalloy 718 fabricated via arc plasma direct energy deposition (IN718 AP-DED) exhibit a limited response to heat treatment due to its coarse primary microstructure and interdendritic segregation, which may prevent its use in high-integrity applications. Thus, dedicated heat treatments for IN718 AP-DED must possess a homogenization temperature as high as possible to significantly dissolve the eutectics and increase the γ′′-former elements in solid-solution. The present work proposed heat treatments for IN718 AP-DED (homogenization – 1050, 1100, 1142, and 1185 °C / 2 h – followed by aging – 718 °C / 8 h, cooling at 56 °C / h, and 621 °C / 8 h). The as-built IN718 AP-DED showed the typical coarse and oriented (cube texture) microstructure with eutectics (Laves and MC-typical carbides) in the interdendritic region, which were significantly dissolved during the homogenization, promoting a high-volume fraction of hardening phase (γ′′ and γ′) and outstanding quasi-static mechanical properties after the aging step. The present work showed that IN718 AP-DED mechanical properties can be optimized through dedicated heat treatments, meeting the ductility and yield strength requirements (room temperature) of AMS 5662. Furthermore, the heat treatments did not alter the grain morphology and texture aspect, inducing a lower Young’s modulus compared to the non-oriented material.

Cell-Free Hemoglobin Induces Vascular and Mitochondrial Dysfunction in the Pulmonary Endothelium in an Oxidation-State Dependent Manner

Background: Sepsis results in significant organ damage due in part to a breakdown in endothelial vascular function. Elevated levels of cell-free hemoglobin (CFH) drive endothelial dysfunction in the lungs. CFH generates reactive oxygen species (ROS) via the iron present in the heme moiety, which can be oxidized from ferrous (CFH2+) to ferric (CFH3+). Recent studies suggest mitochondrial dysfunction may be a key pathway leading to microvascular dysfunction. We hypothesize that CFH induces mitochondrial dysfunction and microvascular endothelial barrier disruption in the lung in an oxidative-state dependent manner. Methods: CFH was converted from CFH2+ to CFH3+ by UV irradiation (validated by spectrophotometry). Primary human lung microvascular endothelial cells (HLMVECs) were treated with 1.0 mg/mL CFH2+, CFH3+, or vehicle control. Barrier dysfunction was measured via electric cell-substrate impedance sensing (ECIS) and express permeability test (XPerT) at 24h. We quantified mitochondrial superoxide (MitoSOX Red; 5 uM) by flow cytometry (1, 6, 24h) and total cellular ROS production (CellROX Deep Red; 5 uM) by fluorescence microscopy (6 and 24 h). Mitochondrial morphology (electron density, roundness, area, circularity, and aspect ratio) was assessed by transmission electron micrographs at 6h and quantified by a blinded reviewer (ImageJ). Activation of the mitochondrial permeability transition pore (mPTP) was assessed by flow cytometry using calcein-AM with cobalt chloride. DNA was purified from patient plasma and the copy number of mitochondrial genes ND4L and CYB was quantified by digital droplet PCR. Results: In HLMVECs, CFH generated excess ROS (CellROX and MitoSOX) at 6h compared to vehicle (522 vs 265 MFI, p < 0.01). Morphology analysis demonstrated increased electron density and aspect ratio and decreased circularity and roundness. mPTP activity was increased by CFH3+ (1295 vs 2197 MFI, p < 0.01) compared to vehicle or CFH2+. Barrier dysfunction caused by CFH3+ measured by ECIS peaked at 6h (-1270 vs 262 max TER drop, p < 0.0001), while XPerT confirmed dysfunction at 24h (9.41e+06 vs 6.53e+05 total fluorescent area, p < 0.01). Quantification of mtDNA copy number in patient plasma revealed that circulating mt-ND4L copies correlate with CFH (r = 0.44, p < 0.01). Conclusions: The results demonstrate significant perturbations to mitochondrial function and network dynamics caused by oxidized CFH (3+). The novel findings point towards the ferric (3+) form of hemoglobin as the primary driver of endothelial dysfunction, and the underlying mechanism is directly related to disruption of the mitochondrial network. The association of mitochondrial and vascular biomarkers demonstrates an urgent need to better understand how mitochondrial dysfunction can be prevented to limit vascular damage. This work was funded by the National Institutes of Health NHLBI 5R35HL150783 and 1F31HL167471. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Characteristic comparison of human induced pluripotent stem cell-derived adult and fetal β-like cells: a differential gene expression analysis

Differentiating human induced pluripotent stem cells (hiPSCs) into β cells for type 1 diabetes (T1D) management is a crucial step. Functionality characterization of hiPSC-derived β cells in some cases, however, only considers morphology and proliferation aspect without examining their distinct molecular properties. Thus, we aimed to investigate the difference between hiPSC-derived adult and fetal β-like cells by differentially expressed gene (DEG) analysis. We retrieved one Gene Expression Omnibus (GEO) dataset with the ID GSE70901 comprising 16 samples and GEO2RAnalyze menu performed the analysis. Network clustering was conducted through the STRING version 12.0, Cytoscape version 3.10.0, and CytoCluster 1.0 plugin by considering overall centrality parameters. Enrichment analysis was performed in DAVID 2021 and updated Enrichr tools. Two main clusters were each related to ribosome and carbohydrate metabolism. Enrichment results showed that some molecular pathways might contrast hiPSC-derived adult from fetal β-like cells, notably ribosome (p value <0.001). Cytoscape identified five significant subclusters with the densest one being ribosomal complex genes, such as RPS2, RPL5, and RPLP0 (p value <0.001). This in silico analysis provides insights into genetic signatures with their potential role in pancreatic β cell maturation, which should be validated in more thorough studies.

TRANSCORACOID DRILLING FOR CORACOCLAVICULAR LIGAMENT RECONSTRUCTIONS IN PATIENTS WITH ACROMIOCLAVICULAR JOINT DISLOCATIONS RESULT IN ECCENTRIC TUNNELS

This study aimed to describe the morphology of the coracoid process and determine the frequency of commonly observed patterns. The second purpose was to determine the location of inferior tunnel exit with superior based tunnel drilling and the superior tunnel exit with inferior based tunnel drilling.A sample of 100 dry scapulae for the morphology aspect and 52 cadaveric embalmed shoulders for tunnel drilling were used. The coracoid process was described qualitatively and categorized into 6 different shapes. A transcoracoid tunnel was drilled at the centre of the base. Twenty-six shoulders were used for the superior-inferior tunnel drilling approach and 26 for the inferior-superior tunnel drilling approach. The distances to the margins of the coracoid process, from both the entry and exit points of the tunnel, were measured.Eight coracoid processes were of convex shape, 31 of hooked shape, 18 of irregular shape, 18 of narrow shape, 25 of straight shape, and 13 of wide shape. The mean difference for the distances between superior entry and inferior exit from the apex was Powered by Editorial Manager® and ProduXion Manager® from Aries Systems Corporation 3.65+3.51mm (p=0.002); 1.57+2.27mm for the lateral border (p=0.40) and 5.53+3.45mm for the medial border (p=0.001). The mean difference for the distances between inferior entry and superior exit from the apex was 16.95+3.11mm (p=0.0001); 6.51+3.2mm for the lateral border (p=0.40) and 1.03+2.32 mm for the medial border (p=0.045).The most common coracoid process shape observed was a hooked pattern. Both superior to inferior and inferior to superior tunnel drilling directed the tunnel from a more anterior and medial entry to a posterior-lateral exit. Superior to inferior drilling resulted in a more posteriorly angled tunnel. With inferior to superior tunnel drilling cortical breaks were observed at the inferior and medial margin of the tunnel.

Eugenol: In Vitro and In Ovo Assessment to Explore Cytotoxic Effects on Osteosarcoma and Oropharyngeal Cancer Cells.

Cancer is a significant health problem worldwide; consequently, new therapeutic alternatives are being investigated, including those found in the vegetable kingdom. Eugenol (Eug) has attracted attention for its therapeutic properties, especially in stomatology. The purpose of this study was to investigate the cytotoxicity of Eug, in vitro, on osteosarcoma (SAOS-2) and oropharyngeal squamous cancer (Detroit-562) cells, as well as its potential irritant effect in ovo at the level of the chorioallantoic membrane (CAM). The data obtained following a 72 h Eug treatment highlighted the reduction in cell viability up to 41% in SAOS-2 cells and up to 37% in Detroit-562 cells, respectively. The apoptotic-like effect of Eug was indicated by the changes in cell morphology and nuclear aspect; the increase in caspase-3/7, -8 and -9 activity; the elevated expression of Bax and Bad genes; and the increase in luminescence signal (indicating phosphatidylserine externalization) that preceded the increase in fluorescence signal (indicating the compromise of membrane integrity). Regarding the vascular effects, slight signs of coagulation and vascular lysis were observed, with an irritation score of 1.69 for Eug 1 mM. Based on these results, the efficiency of Eug in cancer treatment is yet to be clarified.

Abbreviation in Social Media Account Status on Instagram - @Dasadlatif1212: A Morphological Approach

This research discussed “Abbreviation Process in Social Media Status on Instagram @dasadlatif1212 (Review of Morphology Aspect)”. This research is motivated by the widespread modification of the Indonesian language in social media status, both from ordinary people, celebrities, and religious leaders who are active on social media. This research aimed to describe the abbreviation process in social media status on Instagram @dasadlatif1212. This research method used a qualitative descriptive method with a morphological approach. The data in this study were in the form of words or sentences containing abbreviations written in 2020, while the source of data in this study was the status written by the Instagram account @dasadlatif1212. The results show that there are four abbreviation processes in the status of the social media account Instagram @dasadlatif1212, namely the process of letter retention, syllable retention, letter retention, and syllables and word abbreviations that summarize the basic lexeme or lexeme combination.

The effect of non-metallic inclusion morphology on the hydrogen induced cracking (HIC) resistance of L80 steel

The hydrogen induced cracking (HIC) resistance of four (4) L80 casing steels, with different nominal compositions and processing conditions, was determined using the NACE TM0284 HIC test. Microstructural and inclusion characterization of each steel was undertaken using optical microscopy (OM), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). The morphology (equivalent diameter, aspect ratio and major length) of inclusions over identical analysis regions were measured for each steel. In total, >15,000 inclusions were characterized. Non-linear models correlating inclusion morphology with the measured values of CLR (crack length ratio) and CTR (crack thickness ratio) were developed. The models show that both CLR and CTR are complex functions of the diameter (equivalent) of oxide-based inclusions and the major length of the manganese sulfide (MnS) stringers. The models show that oxides <10 μm in diameter were found to have negligible effect on HIC resistance (CLR) while oxides >20 μm exhibited a significant and escalating negative impact on HIC resistance comparable to long (>50 μm) MnS stringers.

Sympatric co-existence of two ecotypes of Impatiens noli-tangere (Balsaminaceae) with different morphology and flowering phenology.

In angiosperms, intraspecific variation of flowering phenology may affect reproductive isolation and, consequently, speciation. This study focused on Impatiens noli-tangere (Balsaminaceae), which is distributed over broad latitudinal and altitudinal ranges in Japan. We aimed to reveal the phenotypic mixture of two ecotypes of I. noli-tangere with different flowering phenology and morphological traits in a narrow contact zone. Previous studies have shown that I. noli-tangere has early- and late-flowering types. The early-flowering type makes buds in June and is distributed at high-elevation sites. The late-flowering type makes buds in July and is distributed at low-elevation sites. In this study, we analyzed the flowering phenology of individuals at an intermediate elevation site where the early- and late-flowering types grow in sympatry (contact zone). We found no individuals showing intermediate flowering phenology at the contact zone, and early- and late-flowering types were clearly distinguishable. We also found that the differences in many other phenotypic traits between the early- and late-flowering types were maintained, including the number of flowers produced (total number of chasmogamous and cleistogamous flowers), leaf morphology (aspect ratio, number of serrations), seed traits (aspect ratio), and flower bud formation positions on the plant. This study showed that these two flowering ecotypes maintain many different traits in sympatry.

Depletion interaction may reduce ice recrystallization inhibition activity of cellulose nanocrystals (CNCs) at high concentrations

In ice cream, food hydrocolloids are commonly used as stabilizers for controlling ice recrystallization. Recent studies suggest that some stabilizers might bind to ice crystal surfaces and inhibit recrystallization. However, this ice-binding mechanism is challenged by the fact that stabilizers at high concentrations sometimes have reduced activity or even accelerate ice recrystallization. In this work, we determined the ice recrystallization inhibition (IRI) activity of cellulose nanocrystals (CNCs) at different concentrations in the 3.0% sucrose solution by the splat assay and in the 25.0% and 40.0% sucrose solutions by the sandwich assay. Reduced activity at high CNCs concentrations was observed in the sandwich assay. It was not linked to the phase separation or liquid crystal phase formation of CNCs but was caused by the accretion of nearby ice crystals and the forming of large ice crystals with irregular morphology and high aspect ratios. A new explanation based on the depletion-interaction-induced accretion of ice crystals was proposed. Our findings might resolve the contradiction between the ice-binding mechanism and the stabilizer concentration effect and add more support to the interfacial mechanism of ice recrystallization inhibition. They also pointed out the importance of selecting suitable stabilizer concentrations for screening IRI active materials and manufacturing frozen desserts.

Effects of the Pore Morphology on Multiphase Fluid Displacement in Porous Media-A High-Resolution Modeling Investigation.

Advances in computational and image acquisition capabilities have made direct simulation of multiphase fluid flow through porous media possible. An example is application of volume of fluid modeling on images produced using the X-ray computed micro-tomography technique. Analysis of such high-resolution (both temporal and spatial) data sets provides new insights into pore-scale dynamics of previously less well-known processes. We present the outcomes of a high-resolution direct-simulation two-phase fluid displacement study performed on a series of five two-dimensional images of sandy porous media produced using erosion and dilation algorithms. This has enabled us to study the pore-scale dynamics systematically in models that are similar in connectivity but different in the morphology (pore sizes and aspect ratio). Our results show that the drainage and imbibition processes result in very distinct fluid displacement patterns in these models at the pore scale. As a result of drainage, the more open (eroded grains) models accommodate large oil clusters, while the tighter (dilated grains) models trap smaller oil clusters. The imbibition process is dominated by oil trapping in two ways: (i) bypassing larger oil clusters in the eroded models and (ii) local trapping of smaller clusters in the dilated models. This behavior is shown to arise from the relatively larger average aspect ratios of the dilated models compared to those of the eroded models. This promotes snap-off at pore throats (in competition with piston-like displacement), resulting in local trapping of the non-wetting phase. Both of these pore-scale trapping regimes seen here allow trapping of oil in as much as 50% of the pore space. Through the use of erosion and dilation operations, we show that a power-law relationship exists between the average pore size and the average grain size for these sandy media. This relationship is useful in designing engineered porous materials where pore sizes need to be estimated based on grain sizes.

ROLE OF SATVAVAJAYA CHIKITSA GRAHANI ROGA

Ayurveda as a complete life science describes various treatment methods. In Ayurveda diseases are mainly classified into Sharirika and Manasika Roga based on its Adhisthana. Grahani Roga is having the Adhisthana of both Sharairika as well as Manasika Roga. Grahani is the seat of Agni, which helps in the digestion and metabolism of consumed food. Any deformity in the morphology and hysiological aspect of this organ will lead to pathophysiological conditions. Ayurvedic classics have given Satwa, Atma and Sharira in the basis of Ayu. So any disturbance in the Ayu i.e. diseases is due to any one or all of the below three reasons. The same concept is applicable in Grahani Roga. According to Acharya Charaka Chikitsa is being divided into three types- Daivavyapashraya, Yuktivyaoashraya, Satvavajaya. Grahani Roga is Psychosomatic Disorder, that’s why Yuktivyapashraya Chikitsa alone is being insufficient for the complete management of many of the diseases. Hence it is the need of time to apply Trividha Chikitsa. Satvavajaya Chikitsa is one among them which helps in Nighrana of Mana from Ahita Indrdiyas.The present paper is aimed at knowing the role of Satva in the Grahani Roga and Satvavajaya Chikitsa in its management. Keywords: Ayurveda, Grahani Roga , Satvavajaya Chikitsa.

Large-scale synthesis of Si3N4 nanowires by a modified carbothermal reduction method using graphite felt as growth substrate

In this work, silicon nitride nanowires (Si3N4NWs) were successfully prepared by a modified carbothermal reduction method, using graphite felt as a growth substrate and in the absence of the catalysts. The synthesized Si3N4NWs exhibited smooth surface, uniform morphology and high aspect ratios. The high purity and high crystallinity of Si3N4NWs were confirmed by XRD, XPS, etc. More importantly, the vapor–solid (VS) growth mechanism of Si3N4NWs was proposed. It is indicated that the graphite felt played a crucial role in increasing the proportion of the gas-phase reaction to obtain large-scale Si3N4NWs. The Si3N4NWs produced by this approach have the advantages of high yield, high purity and low cost, which are very prospective for application.

Behavioral Signatures of Memory Resources for Language: Looking beyond the Lexicon/Grammar Divide.

Although there is a broad consensus that both the procedural and declarative memory systems play a crucial role in language learning, use, and knowledge, the mapping between linguistic types and memory structures remains underspecified: by default, a dual-route mapping of language systems to memory systems is assumed, with declarative memory handling idiosyncratic lexical knowledge and procedural memory handling rule-governed knowledge of grammar. We experimentally contrast the processing of morphology (case and aspect), syntax (subordination), and lexical semantics (collocations) in a healthy L1 population of Polish, a language rich in form distinctions. We study the processing of these four types under two conditions: a single task condition in which the grammaticality of stimuli was judged and a concurrent task condition in which grammaticality judgments were combined with a digit span task. Dividing attention impedes access to declarative memory while leaving procedural memory unaffected and hence constitutes a test that dissociates which types of linguistic information each long-term memory construct subserves. Our findings confirm the existence of a distinction between lexicon and grammar as a generative, dual-route model would predict, but the distinction is graded, as usage-based models assume: the hypothesized grammar-lexicon opposition appears as a continuum on which grammatical phenomena can be placed as being more or less "ruly" or "idiosyncratic." However, usage-based models, too, need adjusting as not all types of linguistic knowledge are proceduralized to the same extent. This move away from a simple dichotomy fundamentally changes how we think about memory for language, and hence how we design and interpret behavioral and neuroimaging studies that probe into the nature of language cognition.

Gold Nanobipyramids as LPSR Sensing Materials for Glyphosate Detection: Surface Density and Aspect Ratio Effect

The governing of localized surface plasmon resonance (LSPR)-based sensor performance is derived with consideration of shape, surface density, and aspect ratio of sensing material, as well as the refractive index of the medium. Dependencies of the surface density and aspect ratio of gold nanobipyramids (GNBPs) used as sensing materials in self-customized LSPR-based sensor setup for the detection of herbicides namely glyphosate are studied in this work. In this work, the GNBPs with a surface density from 5.21% ± 0.44% to 91.46% ± 3.32% and an aspect ratio from 2.00 ± 0.02 to 2.76 ± 0.05 were fabricated. Experimentally, the result shows a linear relationship between the mean surface density and aspect ratio of GNBPs toward the sensitivity of the LSPR-based sensor for both transverse surface plasmon resonance (t-SPR) and longitudinal surface plasmon resonance (l-SPR) resonance peaks. The optimum result for sensitivity was carried out by a sample with a surface density of 80.02% ± 0.86% and an aspect ratio of 2.58 ± 0.04. Furthermore, this sample also exhibits very clear response recovery behavior and stable repeatability up to five cycles with variances of 0.011% and 0.022%, respectively. The findings are useful to enhance the performance of LSPR-based sensor through process conditions that are able to control the morphology (surface density and aspect ratio) of GNBPs to improve the sensitivity of LSPR-based sensor.

Influence of pre-structure orientation on the linear viscoelastic limit of magnetorheological elastomers

Magnetorheological elastomers (MREs) have been developed as a new class of smart materials for such diverse applications as adaptive vibration control of systems and energy dissipation. The linear viscoelastic (LVE) behavior of MREs is expected to play a significant role in determining filler morphology (structure, size, and aspect ratio) and working conditions. The LVE behavior of pre-structures, especially anisotropic structures, has not been clearly explained. To this end, this study aimed to analyze the LVE behavior and dynamic properties according to different pre-structures of magnetic particles. This is based on MRE pre-structures oriented at 0°, 30°, 45°, and 90° using oscillatory shear excitation as a function of frequency and amplitude sweep tests. For the latter, the excitation frequency and magnetic field intensity were analyzed. These analyses were performed for both storage modulus and loss factor corresponding to 10% strain amplitude from the roughly level linear line of the LVE region. The results showed that increasing the frequency or magnetic field intensity to increase anisotropy reduced the LVE limit. For every oriented pre-structure and analyzed frequency tested, the magnetic field decreased the LVE limit. Thus, the orientation of the carbonyl iron particles in the matrix enhanced the viscoelastic properties.

A Facile Method to Synthesize b-Oriented Silicalite-1 Thin Film.

Silicalite-1 thin film was prepared with the following batch composition—3TPAOH:25TEOS:1450H2O:100EtOH—and synthesized using the hydrothermal technique. Silicalite-1 colloidal crystals were successfully coated on the surface of the silica substrate by the dip-coating method. The investigation of silicalite-1 thin film with organic structure-directing agents (SDA), using a seeding technique with various colloidal seed concentrations, number of dip-coating steps, and crystallization time, were systematically discussed and obtained interesting results. Silicalite-1 powder and Silicalite-1 membrane, the patterns of which showed a unique characteristic crystallography of MFI topology, were characterized by XRD, which indicated the preferred orientation along the b-axis perpendicular to the substrate surface. The morphology and crystal size aspect of Silicalite-1 were also examined by a scanning electron microscope (SEM).

Fabrication of High Aspect Ratio Gold Nanowires within the Microtubule Lumen.

Gold nanowires have great potential use as interconnects in electronic, photonic, and optoelectronic devices. To date, there are various fabrication strategies for gold nanowires, each one associated with particular drawbacks as they utilize high temperatures, toxic chemicals, or expensive compounds to produce nanowires of suboptimal quality. Inspired by nanowire fabrication strategies that used higher-order biopolymer structures as molds for electroless deposition of gold, we here report a strategy for the growth of gold nanowires from seed nanoparticles within the lumen of microtubules. Luminal targeting of seed particles occurs through covalently linked Fab fragments of an antibody recognizing the acetylated lysine 40 on the luminal side of α-tubulin. Gold nanowires grown by electroless deposition within the microtubule lumen exhibit a homogeneous morphology and high aspect ratios with a mean diameter of 20 nm. Our approach is fast, simple, and inexpensive and does not require toxic chemicals or other harsh conditions.

Effect of sintering conditions on the radiation shielding characteristics of YBCO superconducting ceramics

The search for protective materials against harmful ionizing Radiation has been increasing dramatically in recent years. High-temperature superconductors could be a pioneer in this field. In this paper, high-temperature superconducting ceramics were fabricated by the solid-state process. The effect of synthesis factors such as sintering temperatures and preparation medium on the structure, morphology, and radiation shielding properties were studied. The X-ray diffraction results showed that YBCO ceramics had been successfully prepared. The scanning electron microscope results showed that the sintering temperatures affected the morphology aspect of the ceramics. The increase of the sintering temperature from 930 °C to 950 °C increased the mean grain size and the physical properties of the ceramics. The ceramics prepared under an oxygen flux atmosphere exhibited the highest grain size (8.53 μm) with the ultra-lowest porosity (1.10%) and improved electrical transport property. Accordingly, the synthesis factors greatly influenced the radiation shielding performance of the prepared ceramics. The analysis was performed using Monte Carlo simulation. The linear attenuation coefficient (μ) was simulated in the energy interval between 0.244 and 2.506 MeV. The results demonstrated that the μ values reduced exponentially from 1.149 to 0.228 cm−1 (for Y93), from 1.255 to 0.249 cm−1 (for Y95A), and from 1.332 to 0.263 cm−1 (for Y95O). Moreover, the fabricated ceramics' attenuation capacity affected the ceramics' sintering temperature. The Y93 sample with a sintering temperature of 930 °C has linear attenuation coefficient values between 1.149 and 0.228 cm−1, which is considered the lowest μ values in the current study. We investigated the relationship between the porosity and the linear attenuation coefficient of the fabricated ceramics, which indicates that the linear attenuation coefficient values decrease linearly with raising the porosity ratio.