Electron Microscopy Studies Research Articles

Enhanced photo-electro catalytic CO2 conversion using transition metal doped TiO2 nanoparticles

The Fe, Co, and Ni-doped TiO2 were synthesised by sol–gel process, and the nanomaterials were coated on electrodes through a slurry with Nafion. This study aims to use prepared nanoparticles of Fe, Co, and Ni-doped TiO2 to enhance the photo-electrocatalytic conversion of CO2. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FTIR), and electrochemical analyses were utilized to characterise the doped and undoped TiO2 nanoparticles. Transmission electron microscopy (TEM) studies revealed that the nanomaterials had an average size below 20 nm. Tauc plot analysis for optical absorption studies shown a reduction in band gap when doped with Fe, Co and Ni, with the most significant decrease observed for Fe-doped TiO2, following the order Fe < Co < Ni. Electrochemical CO2 conversion efficiencies were investigated through cyclic voltammetry (CV) curves, electrochemical impedance spectroscopy (ESI), and linear sweep voltammetry (LSV) studies. The results were analysed based on various scan rates and photo exposure, indicating superior performance for Fe-TiO2, aligning with the observed band gap trends. Gas chromatography (GC) analysis of the reduction products revealed the generation of hydrocarbons, with Fe-TiO2 exhibiting the most favourable outcomes. This research provides valuable insights into tailoring TiO2 nanoparticles for efficient photo-electro catalytic reduction of CO2.

The existence of cells exhibiting characteristics of both Type II and Type III cells in rat taste buds. An immunohistochemical and electron-microscopic study.

Taste bud cells are classified into four types by their ultrastructural features. Immunohistochemical detection of taste-signaling molecules is used to distinguish cell types of taste bud cells; however, the characteristics of taste cell types such as the immunoreactivity for taste-signaling molecules have long remained unclear. We investigated the detailed characteristics of taste cells in rat vallate taste buds by electron microscopy and immunohistochemistry for gustducin, neural cell adhesion molecule (NCAM) and vesicle-associated membrane protein 2 (VAMP2), which are known as markers of Type II cells, Type III cells and both cell types, respectively. Triple immunostaining for these molecules discriminated seven kinds of cell, including the totally immunopositive cell. Electron microscopy revealed Type III cells with a typical synaptic structure and subsurface cisterna as a specialized contact between a nerve and a Type II cell. The present study clarified the existence of cells with features of both Type II and TypeIII cells as a subtype of taste bud cells in the rat taste bud.

#1517 Glomerular immune complex deposits on electron microscopy in ANCA associated vasculitis: clinical and outcomes features

Abstract Background and Aims Glomerulonephritis related to antineutrophil cytoplasmic autoantibodies (ANCA) is typically referred to as “pauci-immune”, however, it is not unusual for kidney biopsies to exhibit some immune complex deposition within glomeruli on electron microscopic study. Such deposits in ANCA-glomerulonephritis have not been widely studied, and their potential pathologic and clinical significance is not clear, although a possible synergistic effect between immune complexes and ANCA in producing more severe glomerulonephritis is suggested in the literature. Method An observational retrospective study was conducted using a dataset comprising all patients with ANCA associated vasculitis diagnosis from a Portuguese Center between march 2011 and march 2023. Demographic and clinical data were collected from medical records. Electron microscopy reports from kidney biopsies were examined for the presence of electron-dense deposits. Descriptive statistics were used to describe all reports. The objective of this study was to explore associations between the presence or absence of such deposits and clinical data, including serum creatinine, urine protein-creatinine ratio levels (PCR) at the time of biopsy as well as overall survival and renal outcomes at follow-up. Non-parametric Mann-Whitney U test and the Chi-squared test were used for continuous and categorical variables respectively. Kaplan-Meier curves were used for assessing time to event data. All analyses were two-tailed and a p value ≤ 0.05 was considered significant. Results From a total of 39 patients with ANCA associated vasculitis diagnosis, 33 underwent at least one kidney biopsy, and among them, 17 were analysed by electron microscopy. 8 (47%) of biopsies showed glomerular immune complex deposits by electron microscopy; Table 1 describes demographic data of both groups (immune complex deposits—D; no-immune complex deposits—ND). The median numbers of glomeruli examined by electron microscopy were identical between the two groups. In group D there was less patients with positive titers for ANCA (p = 0.034) and serum creatinine levels were higher at admission (mean 7.1 mg/dL IQR: 5.6-8.1 versus 4.2 IQR 3.2-7.1), despite the lack of definitive statistical significance (p = 0.123). Urine protein-to-creatinine ratio did not differ between groups. The need for renal replacement therapy at admission was greater for patients with dense deposits on kidney biopsy (p = 0.008). At the end of follow-up (median 48, IQR 24-48 months), death and progression to end stage kidney disease occurred in 25.0% and 37.5% of group D patients versus 11.1% and 22.2% of ND patients, respectively (Fig. 1). Conclusion Immune complex deposits were found on electron microscopy in nearly half of kidney biopsies. Our data suggest that these immune complex deposits are common and might play a role in clinical presentation, overall survival and renal prognosis. The small sample size of our cohort is a limitation, as well as the retrospective nature of the study. Larger cohorts and more comprehensive electron microscopic studies are warranted to better characterize this population.

In vitro anthelmintic efficacy of Ferulic and Sinapic acid against zoonotic cestode Hymenolepis diminuta (Rudolphi, 1819).

The present study is aimed to investigate potential in vitro anthelmintic efficacy of two phenolic compounds Ferulic acid and Sinapic acid against the parasite H. diminuta. Adult parasites collected from infected rat's intestine (maintained in our laboratory) were treated with 1, 2.5, 5, 10 and 20mg/mL concentrations of both the compounds in RPMI-1640 media containing 1% Tween 20. Further, one group was treated in Praziquantel as a reference drug and another group of parasites were kept as control. The efficacy was evaluated on the basis of motility and mortality of the parasites. The paralyzed worms were further processed for the morphological and ultrastructural studies and observed through light and scanning electron microscopy. A significant dose-dependent efficacy was found in all treatment and decrease in relative movability value was also recorded in all the concentrations of two compounds treated parasites. The time taken for paralysis in 5mg/mL of Ferulic acid and 10mg/mL of Sinapic acid were 1.47 ± 0.04h and 0.88 ± 0.03h respectively which is accorded with the standard concentration of Praziquantel. Morphological micrographs revealed pronounced distortion and altered topography of scolex and tegument while histological study showed loss of uniform tegumental integrity with folds and cracks in the treated parasites. Further, extensive alteration in the scolex and irrevocable disruption all over the body surface with loss of trapezoid shape, shrinkage of tegument and sloughing off microtriches were observed in electron microscopic study. The study indicated that both the compounds possess strong activity against H. diminuta and further studies are required to understand their detailed mode of action to exploit them as potential alternative candidates for curing helminthiases.

Design, Synthesis, and Antibacterial Evaluation of Novel Isoindolin-1-ones Derivatives Containing Piperidine Fragments.

A series of novel isoindoline-1-one derivatives containing piperidine moiety were designed and synthesized using natural compounds as raw materials, and their biological activities were tested for three bacterial and three fungal pathogens. These derivatives exhibited good against phytopathogenic bacteria activities against Pseudomonas syringae pv actinidiae (Psa) and Xanthomonas axonopodis pv.citri (Xac). Some compounds exhibited excellent antibacterial activities against Xanthomonas oryzae pv oryzae (Xoo). The dose of Y8 against Xoo (the maximum half lethal effective concentration (EC50) = 21.3 μg/mL) was better than that of the thiediazole copper dose (EC50 = 53.3 μg/mL). Excitingly, further studies have shown that the molecular docking of Y8 with 2FBW indicates that it can fully locate the interior of the binding pocket through hydrogen bonding and hydrophobic interactions, thereby enhancing its anti-Xoo activity. Scanning electron microscopy (SEM) studies revealed that Y8 induced the Xoo cell membrane collapse. Moreover, the proteomic results also indicate that Y8 may be a multifunctional candidate as it affects the formation of bacterial Xoo biofilms, thereby exerting antibacterial effects.

Investigation of the thermal decomposition of Pu(IV) oxalate: a transmission electron microscopy study

The degradation of the internal structure of plutonium (IV) oxalate during calcination was investigated with Transmission Electron Microscopy (TEM), electron diffraction, Electron Energy-Loss Spectroscopy (EELS), and 4D Scanning TEM (STEM). TEM lift-outs were prepared from samples that had been calcined at 300°C, 450°C, 650°C and 950°C. The resulting phase at all calcination temperatures was identified as PuO2 with electron diffraction. The grain size range was obtained with high-resolution TEM. In addition, 4D STEM images were analyzed to provide grain size distributions. In the 300°C calcined sample, the grains were &amp;lt;10 nm in diameter, at 650°C, the grains ranged from 10 to 20 nm, and by 950°C, the grains were 95–175 nm across. Using the Kolmogorov-Smirnov (K-S) two sample test, it was shown that morphological measurements obtained from 4D-STEM provided statistically significant distributions to distinguish samples at the different calcination conditions. Using STEM-EELS, carbon was shown to be present in the low temperature calcined samples associated with oxalate but had formed carbon (possibly graphite) deposits in the 950°C calcined sample. This work highlights the new methods of STEM-EELS and 4D-STEM for studying the internal structure of special nuclear materials (SNM).

Development and characterization of hemp/carbon and hemp/glass hybrid and novel functionally graded hybrid composites for structural applications

AbstractThe main objective of this study is to investigate the effect of combining natural and synthetic fibers on the mechanical characteristics of hybrid and novel functionally graded hybrid composites by considering hemp as natural fiber and carbon and glass as synthetic fibers. Before manufacturing, the natural fibers were treated with sodium hydroxide (NaOH) solution to remove the impurities on the fiber surface. The fibers were reinforced in an epoxy‐based matrix using a hand‐layup technique. The volumetric fraction of the hybrid composites was 40% fibers and 60% matrix. Different types of composites, such as plain fiber reinforced polymer (FRP), sandwich hybrid (SH), alternative hybrid (AH), and functionally graded hybrid (FH), were manufactured from hybridizations of hemp/carbon and hemp/glass. In accordance with ASTM standards, the tensile, compression, flexural, short beam shear, water absorption, and wettability properties of composites were determined. FH composites with hemp fiber at the top surface had the highest improvement in tensile strength, stiffness and compressive strength compared with pure hemp FRP (HFRP) composites. Hemp SH composites had the highest improvement in flexural and short beam properties in both hybridizations compared with HFRP composites due to the stacking of synthetic fiber at the outer layers. Scanning electronic microscopic (SEM) studies identified the failure mechanism of the tensile failure specimens and also the effect of mercerization on fiber surfaces. In conclusion, this work identified the structural capacity of hybrid composites and emphasizes that FH and hemp SH composites can replace glass FRP composites in structural applications.Highlights Treating hemp fiber with 2 g/L of NaOH for an hour had a better impact. Functionally graded composites had better in‐plane strength and stiffness. Composites made with synthetic fiber on the outer layers were good at bending. In structural applications, hemp/carbon hybrid composites can replace GFRP.

Enhancing alkaline resistance of concrete using alccofine and metakaolin in mineral admixtures of sustainable development

Addressing the need for sustainable construction materials that minimize environmental impact and reduce CO2 emissions, particularly in OPC compositions. Assessing alccofine and metakaolin in OPC compositions to determine their impact on concrete strength, durability, and microstructure in alkaline environments for sustainable material development. Experimental investigation involved incorporating alccofine and metakaolin into OPC concrete mixes, creating binary and ternary blended systems. Modified concrete specimens were subjected to various alkaline attacks using diluted solutions of magnesium sulfate (MgSO4), sodium sulfate (Na2SO4), and sodium chloride (NaCl) both individually (5%) and in combination (2.5%), resulting in significant improvements in concrete strength and durability. The modified concrete exhibits enhanced resistance to alkaline attacks, reduced weight and compression strength loss, and superior performance in Base Durability Factor (BDF) and Base Attack Factor (BAF) compared to conventional specimens. Scanning electron microscopy (SEM) study of the altered concrete’s microstructure shows that it has a densely packed microstructure, which increases its load-bearing capability. Mineral admixtures aid pore clogging, leading to denser, more alkali-resistant concrete due to finer particles. Notably, Alccofine and metakaolin offer effective solutions for sustainable construction materials, aiding in the decrease of CO2 releases during cement production and addressing critical gaps in sustainable material development.

Micronization induced gelatinization of tapioca starch and its effects on starch physicochemical and structural properties.

The vibrating superfine mill (VSM) is a machine that belongs to the micronization technique. In this study, VSM was employed to produce micronized tapioca starch by varying micronization times (15, 30, 45, and 60min). The structural and physicochemical properties of the micronized starch were then examined. Scanning electron microscopy studies revealed that micronized starch was partially gelatinized, and the granule size dramatically increased when micronization time increased. X-ray diffraction patterns showed that the relative crystallinity was decreased from 24.67% (native) to 4.13% after micronization treatment for 15min and slightly decreased after that. The solubility of micronized starch significantly increased as the micronization time increased, which was associated with the destruction of the starch crystalline structure. Differential scanning calorimetry investigations confirmed that micronized starch was "partly gelatinized," and the degree of gelatinization increased to 81.27% when the micronization time was 60min. The weight-average molar mass was reduced by 15.0% (15min), 30.9% (30min), 55.7% (45min), and 70.5% (60min), respectively, indicating that the molecular structure was seriously degraded. The results demonstrated that the physicochemical changes of micronized starch granules were related to the destruction of the starch structure. These observations would provide details on micronized starch and its potential applications. PRACTICAL APPLICATION: These observations would provide details on micronized starch and its potential applications. Moreover, we believe that when the structures of starches were known, it is probable that the effect of VSM on the structural and physicochemical properties change of other starches might be predicted by adjusting the processing time.

Exploring the Progress of Hyaluronic Acid Hydrogels: Synthesis, Characteristics, and Wide-Ranging Applications.

This comprehensive review delves into the world of hyaluronic acid (HA) hydrogels, exploring their creation, characteristics, research methodologies, and uses. HA hydrogels stand out among natural polysaccharides due to their distinct features. Their exceptional biocompatibility makes them a top choice for diverse biomedical purposes, with a great ability to coexist harmoniously with living cells and tissues. Furthermore, their biodegradability permits their gradual breakdown by bodily enzymes, enabling the creation of temporary frameworks for tissue engineering endeavors. Additionally, since HA is a vital component of the extracellular matrix (ECM) in numerous tissues, HA hydrogels can replicate the ECM's structure and functions. This mimicry is pivotal in tissue engineering applications by providing an ideal setting for cellular growth and maturation. Various cross-linking techniques like chemical, physical, enzymatic, and hybrid methods impact the mechanical strength, swelling capacity, and degradation speed of the hydrogels. Assessment tools such as rheological analysis, electron microscopy, spectroscopy, swelling tests, and degradation studies are employed to examine their attributes. HA-based hydrogels feature prominently in tissue engineering, drug distribution, wound recovery, ophthalmology, and cartilage mending. Crafting HA hydrogels enables the production of biomaterials with sought-after qualities, offering avenues for advancements in the realm of biomedicine.

Ameliorative Potential of Bone Marrow-Derived Mesenchymal Stem Cells Versus Prednisolone in a Rat Model of Lung Fibrosis: A Histological, Immunohistochemical, and Biochemical Study.

Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease of unknown origin with limited treatment options and poor prognosis. The encouraging findings from preclinical investigations utilizing mesenchymal stem cells (MSCs) indicated that they could serve as a promising therapeutic alternative for managing chronic lung conditions, such as IPF. The objective of this study was to compare the efficiency of bone marrow-derived MSCs (BM-MSCs) versus prednisolone, the standard anti-inflammatory medication, in rats with bleomycin (BLM)-induced lung fibrosis. Four groups were created: a control group, a BLM group, a prednisolone-treated group, and a BM-MSCs-treated group. To induce lung fibrosis, 5 mg/kg of BLM was administered intratracheally. BLM significantly increased serum levels of pro-inflammatory cytokines and oxidative stress markers. The disturbed lung structure was also revealed by light and transmission electron microscopic studies. Upregulation in the immune expression of alpha-smooth muscle actin, transforming growth factor beta-1, and Bax was demonstrated. Interestingly, all findings significantly regressed on treatment with prednisolone and BM-MSCs. However, treatment with BM-MSCs showed better results than with prednisolone. In conclusion, BM-MSCs could be a promising approach for managing lung fibrosis.

Advanced modelling tool to extract the structural state boundaries from the hardness-strain experiments

High pressure torsion (HPT) is the way to form nanostructured materials with high strength properties. HPT hardening mechanisms in BCC metals, such as niobium and vanadium, are not fully understood. Here, we have demonstrated that a recently proposed piecewise model can extract from the hardness-strain experimental data the different structural states in BCC metals. The piecewise model, with overlapped stages, is based on an assumption that two separate deformation mechanisms which are responsible for the type of structure have overlapped strain region. To confirm/disprove extracted boundary values, we performed a transmission electron microscopic study of the HPT niobium and vanadium. We found that the piecewise model provides accurate extraction of the boundaries in niobium and vanadium. We proposed an explanation for the observed difference in the structure formation/transformation in niobium and vanadium upon HPT.

Infection-Free and Enhanced Wound Healing Potential of Alginate Gels Incorporating Silver and Tannylated Calcium Peroxide Nanoparticles.

The treatment of chronic wounds involves precise requirements and complex challenges, as the healing process cannot go beyond the inflammatory phase, therefore increasing the healing time and implying a higher risk of opportunistic infection. Following a better understanding of the healing process, oxygen supply has been validated as a therapeutic approach to improve and speed up wound healing. Moreover, the local implications of antimicrobial agents (such as silver-based nano-compounds) significantly support the normal healing process, by combating bacterial contamination and colonization. In this study, silver (S) and tannylated calcium peroxide (CaO2@TA) nanoparticles were obtained by adapted microfluidic and precipitation synthesis methods, respectively. After complementary physicochemical evaluation, both types of nanoparticles were loaded in (Alg) alginate-based gels that were further evaluated as possible dressings for wound healing. The obtained composites showed a porous structure and uniform distribution of nanoparticles through the polymeric matrix (evidenced by spectrophotometric analysis and electron microscopy studies), together with a good swelling capacity. The as-proposed gel dressings exhibited a constant and suitable concentration of released oxygen, as shown for up to eight hours (UV-Vis investigation). The biofilm modulation data indicated a synergistic antimicrobial effect between silver and tannylated calcium peroxide nanoparticles, with a prominent inhibitory action against the Gram-positive bacterial biofilm after 48 h. Beneficial effects in the human keratinocytes cultured in contact with the obtained materials were demonstrated by the performed tests, such as MTT, LDH, and NO.

Highly adsorptive removal of heavy metal, dye, and antibiotic pollutants using functionalized graphene nanosheets sono-electrochemically derived from graphitic waste

The development of highly adsorptive materials at low cost is critically important for efficient treatment of industrial wastewater. We herein report a one-step sonoelectrochemical strategy to synthesize functionalized graphene (FG) nanosheets as an effective adsorptive material using graphite waste from spent household batteries. Scanning/transmission electron and Raman microscopy studies reveal that the as-synthesized nanosheets are composed of few (2–6) graphene layers. Additionally, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy analyses imply the presence of oxygen functional groups on the nanosheets (CO and -COOH, oxygen content of 4.29%), which are immensely beneficial for the electrostatic adsorption with heavy metals, dyes, and antibiotics in aqueous solutions. As expected, FG nanosheets exhibit potent capabilities of handling a wide range of pollutants, such as methylene blue, methyl orange, enrofloxacin, and Pb2+, with high adsorption performances (99.95% and 21.21 mg/g for Enrofloxacin, 98.93% and 119.3 mg/g for methylene blue, 95.82% and 25.67 mg/g for methyl orange, 95.56% and 86.10 mg/g for Pb2+). These findings therefore show a great promise for practical uses of the FG material as efficient adsorbents in eliminating metallic, organic, and antibiotic pollutants in water.

Exploring Zinc Vanadate/Cobalt Oxide (Zn3(VO4)2/CoO) Nano Hybrid Composites as Supercapacitors for Sustainable Energy Storage Applications

A hybrid nanocomposite of zinc vanadate/cobalt oxide (Zn3(VO4)2/CoO at ratios of 90/10, 80/20, 50/50, and 20/80) was obtained using a simple co-precipitation technique, then calcinated for 4 hrs at 400°C. The surface morphological, vibrational, and structural characteristics of the synthesized hybrid nanocomposites were examined. According to the structural study, orthorhombic Zn3(VO4)2 and cubic crystal systems of CoO with space groups Fm-3m were formed. The functional groups of Zinc Vanadate/Cobalt Oxide were examined using FTIR spectroscopy. A scanning electron microscopy (SEM) study reveals the nanosheets structures with the size of 200 nm. The chemical composition and formation of the Zn3(VO4)2/CoO composites were confirmed using X-ray photoelectron spectroscopy (XPS). The electrochemical performance of the hybrid nanocomposites was assessed through CV, GCD and impedance analysis. Among the nanocomposites, Zn3(VO4)2/CoO 80/20 exhibited a high specific capacitance value of 564.36 Fg-1 and retaining 97% of their total capacitance even after 3000 cycles.

Crystal structures of two new high-pressure oxynitrides with composition SnGe4N4O4, from single-crystal electron diffraction.

SnGe4N4O4 was synthesized at high pressure (16 and 20 GPa) and high temperature (1200 and 1500°C) in a large-volume press. Powder X-ray diffraction experiments using synchrotron radiation indicate that the derived samples are mixtures of known and unknown phases. However, the powder X-ray diffraction patterns are not sufficient for structural characterization. Transmission electron microscopy studies reveal crystals of several hundreds of nanometres in size with different chemical composition. Among them, crystals of a previously unknown phase with stoichiometry SnGe4N4O4 were detected and investigated using automated diffraction tomography (ADT), a three-dimensional electron diffraction method. Via ADT, the crystal structure could be determined from single nanocrystals in space group P63mc, exhibiting a nolanite-type structure. This was confirmed by density functional theory calculations and atomic resolution scanning transmission electron microscopy images. In one of the syntheses runs a rhombohedral 6R polytype of SnGe4N4O4 could be found together with the nolanite-type SnGe4N4O4. The structure of this polymorph was solved as well using ADT.

OSMOTIC DRUG DELIVERY SYSTEM OF NICORANDIL: DESIGN AND EVALUATION

Objective: The purpose of the current research was to design a nicorandil formulation with controlled drug release using the principles of osmotic pump technology. Nicorandil is a biopharmaceutical classification system (BCS) class 3 drug, having a shorter plasma elimination half-life and bioavailability of 75 to 80%. Methods: The elementary osmotic pump (EOP) was prepared by coating a cellulose acetate polymer on the prepared core tablet. A 24-factorial design was applied to optimize the parameters for the osmotic tablet. A surface orifice was drilled. Results: Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and powder X-ray diffraction (PXRD) results showed that there was no interaction between drugs and excipients. A 24-factorial design was applied to optimize the parameters for the elementary osmotic pump. The optimized batch was characterized for in vitro drug release studies, and the effects of pH, osmotic pressure, and agitation intensity were analyzed. All the batches showed a drug release ranging from 90.48% to 98.78% after 12 hours. There was no change in the drug release pattern at different pHs and agitation intensities. The drug release was found to decrease with the increasing osmotic pressure of the dissolution medium. The results showed that the amounts of sodium chloride and mannitol were positively affecting the drug release, while the plasticizers PEG400 and DBP were not critical. Scanning electron microscopic studies (SEM) showed the integrity and surface morphology of the coating membrane before and after dissolution. The prepared EOP was found to deliver nicorandil at zero-order for up to 12 hours. Conclusion: Nicorandil was developed successfully as a controlled drug delivery during a 12-hour period, with variables optimized by the use of a 24-factorial design.

Biochemical and immunomodulatory insights of extracellular matrix from decellularized human whole cervix: recellularization and in vivo ECM remodeling interplay

Extracellular matrix (ECM) rich whole organ bio-scaffolds, preserving structural integrity and essential growth factors, has potential towards regeneration and reconstruction. Women with cervical anomalies or trauma can benefit from clinical cervicovaginal repair using constructs rich in site specific ECM. In this study, complete human cervix decellularization was achieved using a modified perfusion-based stir bench top decellularization method. This was followed by physico-chemical processes including perfusion of ionic agents, enzymatic treatment and washing using detergent solutions for a duration of 10–12 d. Histopathological analysis, as well as DNA quantification confirmed the efficacy of the decellularization process. Tissue ultrastructure integrity was preserved and the same was validated via scanning electron microscopy and transmission electron microscopy studies. Biochemical analysis and structural characterizations like Fourier transform infrared, Raman spectroscopy of decellularized tissues demonstrated preservation of important proteins, crucial growth factors, collagen, and glycosaminoglycans. In vitro studies, using THP-1 and human umbilical vein endothelial cell (HUVEC) cells, demonstrated macrophage polarization from M1 to M2 and vascular functional genes enhancement, respectively, when treated with decellularized human cervical matrix (DHCp). Crosslinked DHC scaffolds were recellularized with site specific human cervical epithelial cells and HUVEC, showing non-cytotoxic cell viability and enhanced proliferation. Furthermore, DHC scaffolds showed immunomodulatory effects in vivo on small rodent model via upregulation of M2 macrophage genes as compared to decellularized rat cervix matrix scaffolds (DRC). DHC scaffolds underwent neo-vascularization followed by ECM remodeling with enhanced tissue integration.

Corrosion resistance of chromium coating on the inner surface of EP823-Sh steel cladding

The processes of corrosion damage of the inner surface of the cladding are determined by corrosive reagents aggressive with respect to the cladding and the type of fuel used. Reactor irradiation of cladding made of EP823-Sh steel with mixed nitride fuel planned for use in the BREST-OD-300 reactor revealed non-uniform corrosion of the inner surface of the cladding. In this paper, the use of the chromium coating is proposed to prevent the corrosion of the inner surface of the steel fuel cladding. The results of corrosion tests of chromium coating applied to the inner surface of cladding made of EP823-Sh steel by electrolytic deposition are presented. Electron-microscopic studies of the chromium coating on EP823-Sh steel showed no significant signs of corrosion damage when tested in the environment of simulant fission products (CsI+Te) and in liquid lead at 650 °C.

Facile fabrication of functional poly (para-phenylenediamine) nanotubes using self-degraded methyl orange template

Polyaniline (PANI) derivatives, such as poly(phenylenediamine) (para, ortho and meta derivatives) and their nanostructures are attracting immense interest in wide potential applications due to their unique multifunctionality. Here, we report synthesis of polymer nanotubes from poly (para-phenylenediamine) (PpPD) by a simple self-degrading template method using methyl orange (MO) as the structure-directing template and potassium persulfate (KPS) as the oxidant. Two experiment schemes with reversed additions of monomer and oxidant are tested and they demonstrate influence on morphology of the as-produced materials. Electron microscopy and diffraction studies show that the nanotubes with 80 −100 nm outer diameter and more than 1 μm in length, exhibit rectangular cross-section and partial crystallinity. The chemical structures of the material are characterized by EDX, FTIR and UV-Visible spectroscopy. Results show that PpPD nanotubes could be successfully prepared by the facile solution route and demonstrate that the MO template is versatile for preparing nanotubes for not only of conducting polymer but also for its derivative.