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Due to their magnetic and electrical properties, ceramic ferrite nanoparticles are a suitable option for use in various industries, including pharmaceutical, biomedical, food, and environmental. A total of 40 Gram-positive actinomycetes strains (named Ak1–40) were isolated from the soil and used to synthesize ceramic ferrite nanoparticles. To determine the identity of the isolated actinomycetes, its colonies were characterized morphologically using a scanning electron microscope (SEM). The PCR amplification (FD1 and RP2 primers) of 16 S rDNA gene was done to the genetically identification of the bacterial strain. Bacterial Streptomyces fulvissimus (isolate Ak10) was able to restore the production of ceramic ferrite nanoparticles. The characteristics of ceramic ferrite nanoparticles were examined through Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), and Vibrating Sample Magnetometry (VSM). The size of synthesized ceramic ferrite nanoparticles was less than 50 nm. This study is the first report on synthesizing ceramic ferrite nanoparticles by actinomycete soil bacteria. Using bacteria in synthesizing nanoparticles as nano-factories is a promising tool for the biological production of ceramic ferrite nanoparticles. [ABSTRACT FROM AUTHOR]

Porous hematite α-Fe2O3 nanoparticles (NPs) were synthesized using plant extract. The physicochemical characteristics of resulting porous particles were determined using X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), energy dispersive X-ray (EDS), High-Resolution Transmission Electron Microscopy (HR-TEM), vibrating sample magnetometer (VSM) and N2 adsorption–desorption isotherms (BET) analyses. The cytotoxicity of porous magnetic α-Fe2O3 (PMΑ) NPs, free anticancer drug, and anticancer drug-coated PMΑ NPs was evaluated against melanoma cell line (A375) and normal human cells using MTT and LDH leakage assays. BET results confirmed the presence of porous particles with the mean pore diameter of 18 nm. Porous NPs have spherical surface morphology and rhombohedral crystal structures. It was revealed that both free anticancer drug and anticancer drug-coated PMΑ NPs could inhibit the cell growth in a concentration-dependent manner. However, anticancer drug-loaded PMΑ NPs had better cytotoxic effects against melanoma cell line, evidenced via MTT and LDH leakage assays. Additionally, anticancer drug-loaded PMΑ NPs induced morphological alterations compatible with the occurrence of apoptotic cell death. [ABSTRACT FROM AUTHOR]

Bimetallic nanoparticles offer unique chemical, physical and optical properties that are not available for monometallic nanoparticles. Bimetallic nanoparticles play a major role in various therapeutic, industrial and energy fields. Recently, nanoparticles of Copper/Zinc bimetallic nanoparticles have attracted attention in various fields, especially medicine. In this study, bimetallic CuO/ZnO nanostructures were biosynthesized using plant extracts. The plant-mediated synthesis nanoparticles were characterized by Transmission electron microscopy (TEM), X-ray diffraction analysis (XRD), Field Emission Scanning Electron Microscopy (FESEM) and Energy-Dispersive Spectroscopy (EDAX). The cytotoxicity of plant-mediated synthesis bimetallic nanoparticles and the synergistic effects of these nanoparticles in combination with the anticancer drug doxorubicin on MCF-7 cancer cells were evaluated by MTT assay. [ABSTRACT FROM AUTHOR]

The aim of this research was to optimize and model the synthesis and application of a novel visible-light-driven Ag/C-TiO2 nanophotocatalyst for degradation of recombinant DNA in Hepatitis B surface antigen production plant wastewater. The synthesized nanoparticles were characterized using X-ray diffraction, Fourier transform infrared spectroscopy, UV–Vis diffuse reflectance spectra, field emission scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The effects of the dopant content of silver and carbon, calcination temperature, heating rate, initial recombinant DNA copy number, pH value, and contact time were evaluated experimentally and optimized separately as the synthesis and operational parameters. Application of response surface methodology showed the optimum values of Ag content, C content, calcination temperature, and the heating rate as 2.2 wt%, 0.06 wt%, 444 °C, and 12 °C/min, respectively. Synthesized nanoparticles resulted in 60% recombinant DNA degradation at the optimized operation conditions experimentally (i.e., pH of 5.5, contact time of 24 h, and the maximum initial recombinant DNA concentration of 2.12E13 copy number in 200 mL wastewater). The synthesis and operating quadratic models adequately predicted the experimental data. The statistical analysis showed that the square of carbon dopant content, calcination temperature, initial recombinant DNA concentration, and contact time had the greatest effects on the recombinant DNA degradation. [ABSTRACT FROM AUTHOR]

Background: Familial adenomatous polyposis (FAP) is an Autosomal dominant inherited disorder and a rare form‌ of colorectal cancer (CRC) that is characterized by the development of hundreds to thousands of adenomas in the rectum and colon. Mostly, cancers develop after the advent of the polyps. It appears in both sexes evenly, and the occurrence of the disease is in the second decade of life. Mitochondrial genome mutations have been reported with a variety of Tumors, but the precise role of these mutations in the pathogenicity and tumor progression is not exactly clear. Cytochrome c oxidase subunit I (COX1) is the terminal enzyme of the mitochondrial respiratory chain. The present study aims at assessing the occurrence of mtDNA mutations in COX1 gene in FAP patients and attempts to find out the cause and effect relationship between mitochondrial mutations and tumor progression. Methods: In this study, 56 FAP patients were investigated for the presence of the mutations in mitochondrial COX1 coding gene by PCR and sequencing analysis. All sequences that differed from the revised Cambridge Reference Sequence (rCRS) were classified as missense/ nonsense or silent mutations. Functional genomic studies using Bio-informatics tools were performed on the founded mutations to understand the downstream alterations in structure and function of protein. Results: We identified 38 changes in the COX1 gene in patients with FAP symptoms. Most of them were heteroplasmic changes of missense type (25/38). Tree of the changes (G6145A, C6988A, and T7306G) were nonsense mutations and had not been reported in the literature before. Our results of bioinformatics predictions showed that the identified mutations can affect mitochondrial functions, especially if the conservative domain of the protein is concerned. Conclusion: Our findings indicate a high frequency of mtDNA mutations in all of the FAP cases compared to matched controls. These data significantly enhance our understanding of how such mutations contribute to cancer pathologies and develop the cancer treatment methods by new diagnostic biomarkers, and new drugs for gene therapy. [ABSTRACT FROM AUTHOR]

Let M(n, d) be the maximum size of a permutation code of length n and distance d. In this note, the permutation codewords of a classical code C are considered. These are the codewords with all different entries in C. Using these codewords for Reed–Solomon codes, we present some good permutation codes in this class of codes. As a consequence, since these codes are subsets of Reed–Solomon codes, decoding algorithms known for Reed–Solomon codes can also be used as a decoding algorithm for them. [ABSTRACT FROM AUTHOR]

The amorphous Co80−xErxB20 alloys with x = 0, 3.9, 5.5 and 8.6% have been prepared by melt spinning in pure argon atmosphere. The electrical resistivity has been measured over the temperature range from 4.2 to 300 K. All investigated amorphous alloys exhibit a logarithmic resistivity versus temperature below the temperature of the resistivity minimum Tmin. In addition, the resistivity shows a quadratic temperature behavior in the temperature range Tmin < T < 77 K. At high temperature, the electrical resistivity was discussed by the extended Ziman theory. For the studied alloys, the composition dependence of the temperature coefficient of electrical resistivity α shows a change in sign related to a structural short-range that is occurring in the composition range 8–9%. [ABSTRACT FROM AUTHOR]

The magnetotransport properties of NiFe/WTi multilayers are investigated. The effect of the thicknesses of magnetic (NiFe) and nonmagnetic (WTi) layers on the magnetoresistance (MR) is theoretically discussed in the framework of the Johnson-Camley semiclassical approach based on the Boltzmann transport equation. A comparison between the calculated and measured MR ratios is obtained. The observed MR ratio oscillates for WTi layer thickness with an average period of 10 Å. A weak MR(t) ratio for a fixed t is obtained, and it presents a maximum peak of the MR with a value of 0.8 % located at t = 50 Å. In addition, electronic and magnetic properties of multilayers are investigated by self-consistent ab initio calculations based on the Korringa-Kohn-Rostocker (KKR) approximation. Spin polarized within the framework of the coherent potential approximation (CPA) is considered for calculations. [ABSTRACT FROM AUTHOR]

Let G be a finite group and N be a normal subgroup of G. Suppose that the set of G-conjugacy class sizes of N is {1, m, n}, with m < n and m does not divide n. In this paper, we show that N is solvable, and we determine the structure of these subgroups. [ABSTRACT FROM AUTHOR]

Let G be a finite non-abelian group. The noncommuting graph of G is denoted by ∇(G) and is defined as follows: the vertex set of ∇(G) is G\Z(G) and two vertices x and y are adjacent if and only if xy ≠ yx. Let p be a prime number. In this paper, it is proved that the almost simple group PGL(2; p) is uniquely determined by its noncommuting graph. As a consequence of our results the validity of a conjecture of Thompson and another conjecture of Shi and Bi for the group PGL(2, p) are proved. [ABSTRACT FROM AUTHOR]

As the main result, we show that if G is a finite group such that Γ( G) = Γ(2 F4( q)), where q = 22 m+1 for some m ≧ 1, then G has a unique nonabelian composition factor isomorphic to 2 F4( q). We also show that if G is a finite group satisfying | G| =|2 F4( q)| and Γ( G) = Γ(2 F4( q)), then G ≅ 2 F4( q). As a consequence of our result we give a new proof for a conjecture of W. Shi and J. Bi for 2 F4( q). [ABSTRACT FROM AUTHOR]

Friedreich's ataxia (FRDA), an autosomal recessive neurodegenerative disorder, is in most cases due to a homozygous intronic expansion resulting in the loss of function of frataxin. As mitochondrial DNA (mtDNA) copy number has been decreased in FRDA cells and mtDNA polymerase (POLG) is involved in the replication of mtDNA, we searched a trinucleotide CAG repeat length of this enzyme. The POLG CAG repeat length was determined in DNA samples extracted from 20 FRDA patients and 49 control subjects. Our findings showed that the distribution of the POLG CAG repeat length in the patients' samples matched the distribution for control samples, but we found a statistically significant inverse correlation (r=-0.81) between the POLG CAG repeats and age of onset in FRDA patients. Our results suggest POLG CAG repeat instability would constitute a predisposing factor that, in combination with environmental risk factors, affect age of onset and disease progression. [ABSTRACT FROM AUTHOR]