Unusually large magnetite (Fe3O4) crystals inside a magnetotactic bacterium

1990 ◽  
Vol 48 (3) ◽  
pp. 588-589
Author(s):  
Marcos Farina ◽  
Henrique G.P. Lins de Barros ◽  
Darci M.S. Esquivel
Keyword(s):  
Electron Diffraction ◽  
Southern Hemisphere ◽  
Rio De Janeiro ◽  
Magnetotactic Bacterium ◽  
Previous Communication ◽  
Magnetite Fe3o4 ◽  
Wide Range ◽  
Almost All

Magnetite crystals inside magnetotactic microorganisms have been shown to cover a wide range of dimensions and shapes. However in almost all cases reported until now, crystals width and length remain under the magnetite monodomain dimensions when using Butler and Banerjee theoretical curves. We report here one type of magnetotactic bacterium which produces very large magnetite crystals as compared with those described in the literature. In a previous communication we had notified this fact, but without detail.Samples were collected from brakish water from ITAIPU lagoon near Rio de Janeiro (24° Southern hemisphere). In the same sample it was possible to find different magnetotactic microorganisms. After standard isolation treatments we obtained different groups of crystals identifyed as magnetite (Fe3O4) by electron diffraction.

Unusually large magnetite (Fe3O4) crystals inside a magnetotatic bacterium

1990 ◽  
Vol 48 (4) ◽  
pp. 1084-1085
Author(s):  
Marcos Farina ◽  
Henrique G.P. Lins ◽  
Darci M.S. Esquivel
Keyword(s):  
Electron Microscope ◽  
Electron Diffraction ◽  
Southern Hemisphere ◽  
Rio De Janeiro ◽  
Magnetotactic Bacterium ◽  
Previous Communication ◽  
Linear Chains ◽  
Magnetite Fe3o4 ◽  
Wide Range ◽  
Almost All

Magnetite crystals inside magnetotactic microorganisms have been shown to cover a wide range of dimensions and shapes. However in almost all cases reported until now, crystals width and length remain under the magnetic monodomai dimensions when using Butler and Banerjee theoretical curves. We report here one type of magnetotactic bacterium which produces very large magnetite crystals as compared with those described in the literature. In previous communication we had notified this fact, but without detail. Samples were collected from brakish water from ITAIPU lagoon near Rio de Janeiro (24º Southern hemisphere). In the same sample it was possible to find different magnetotactic microorganisms.After standard isolation treatments we obtained different groups of crystals identifyed as magnetite (Fe3O4) by electron diffraction. It was observed that larger crystals(> 1000 Aº in length) stayed always closely attached in linear chains differently from smaller ones appearing as rolled chains under the electron microscope (Fig.l).

Topics of Environmental Education Program in Coastal Areas

1992 ◽  
Vol 25 (9) ◽  
pp. 253-259 ◽  
Author(s):  
A. M. O. Rennhack ◽  
D. M. W. Zee ◽  
E. S. Cunha ◽  
M. F. Portilho
Keyword(s):  
Environmental Education ◽  
Rio De Janeiro ◽  
Local Community ◽  
Environmental Problems ◽  
Coastal Areas ◽  
State University ◽  
Urban Centers ◽  
Educational Support ◽  
Wide Range ◽  
Supply Information

Researches and Studies made by the Department of Oceanography of the Institute of Geoscience of the State University of Rio de Janeiro UERJ, evidenced the need for educational support where environment-related questions were concerned. A wide range of environment problems tend to concentrate in coastal areas, owing to disordinate urban growth combined with the lack of substructure to cope with it A large number of these problems can be minimized through the participation of the local community. Thus the goals of environmental education are to supply information, to promote a change in the population's attitude toward environmental problems, besides stimulating its participation by fostering its sense of responsibility. Preliminary results have demonstrated that the community has shown great interest in the work that has been proposed, and it has contributed with participation, promising response. Environmental education is fundamental when we consider possible solutions for environmental problems in coastal urban centers. Only by educating the main cause of environmental problems, man himself, will it be possible to consider the question starting from its very origin. This abstract presents two pioneer experiments in the Municipio of Rio de Janeiro, which are “Muito Prazer Marapendi” (“Glad to know you, Marapendi”) and “Troca de Areias da Praia de Copacabana” (“Exchange of Sands in Copacabana Beach”).

First Detection of Tobacco Mosaic Virus in Tobacco Fields in Northern Lebanon

2020 ◽  
Vol 20 ◽  
Author(s):  
Rami Obeid ◽  
Elias Wehbe ◽  
Mohamad Rima ◽  
Mohammad Kabara ◽  
Romeo Al Bersaoui ◽  
...  
Keyword(s):  
Tobacco Mosaic Virus ◽  
Mosaic Virus ◽  
Viral Genome ◽  
Virus Genome ◽  
Enzyme Linked Immunosorbent Assay ◽  
Virus Family ◽  
Crop Fields ◽  
Wide Range ◽  
Almost All ◽  
Das Elisa

Background: Tobacco mosaic virus (TMV) is the most known virus in the plant mosaic virus family and is able to infect a wide range of crops, in particularly tobacco, causing a production loss. Objectives: Herein, and for the first time in Lebanon, we investigated the presence of TMV infection in crops by analyzing 88 samples of tobacco, tomato, cucumber and pepper collected from different regions in North Lebanon. Methods: Double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA), revealed a potential TMV infection of four tobacco samples out of 88 crops samples collected. However, no tomato, cucumber and pepper samples were infected. The TMV+ tobacco samples were then extensively analyzed by RT-PCR to detect viral RNA using different primers covering all the viral genome. Results and Discussion: PCR results confirmed those of DAS-ELISA showing TMV infection of four tobacco samples collected from three crop fields of North Lebanon. In only one of four TMV+ samples, we were able to amplify almost all the regions of viral genome, suggesting possible mutations in the virus genome or an infection with a new, not yet identified, TMV strain. Conclusion: Our study is the first in Lebanon revealing TMV infection in crop fields, and highlighting the danger that may affect the future of agriculture.

INFLUENCE OF WEATHER ON TEMPORARY AND PERMANENT MIGRATION IN RURAL INDIA

2013 ◽  
Vol 04 (02) ◽  
pp. 1350007 ◽  
Author(s):  
K. S. KAVI KUMAR ◽  
BRINDA VISWANATHAN
Keyword(s):  
National Sample ◽  
Sample Survey ◽  
Urban Migration ◽  
Temporary Migration ◽  
Urban Migrants ◽  
Wide Range ◽  
Permanent Migration ◽  
Sample Survey Data ◽  
Almost All ◽  
Temporary Migrants

While a wide range of factors influence rural–rural and rural–urban migration in developing countries, there is significant interest in analyzing the role of agricultural distress and growing inter-regional differences in fueling such movement. This strand of research acquires importance in the context of climate change adaptation. In the Indian context, this analysis gets further complicated due to the significant presence of temporary migration. This paper analyzes how weather and its variability affects both temporary and permanent migration in India using National Sample Survey data for the year 2007–2008. The paper finds that almost all of the rural–urban migrants are permanent. Only temperature plays a role in permanent migration. In contrast, many temporary migrants are rural–rural and both temperature and rainfall explain temporary migration.

scholarly journals Isolation and Characterization of Bacteriophage ZCSE6 against Salmonella spp.: Phage Application in Milk

Biologics ◽  
2021 ◽  
Vol 1 (2) ◽  
pp. 164-176
Author(s):  
Abdallah S. Abdelsattar ◽  
Anan Safwat ◽  
Rana Nofal ◽  
Amera Elsayed ◽  
Salsabil Makky ◽  
...  
Keyword(s):  
Pathogenic Bacteria ◽  
Raw Milk ◽  
Salmonella Spp ◽  
Isolation And Characterization ◽  
Food Borne ◽  
Wide Range ◽  
Almost All ◽  
And Control ◽  
Milk And Dairy Products

Food safety is very important in the food industry as most pathogenic bacteria can cause food-borne diseases and negatively affect public health. In the milk industry, contamination with Salmonella has always been a challenge, but the risks have dramatically increased as almost all bacteria now show resistance to a wide range of commercial antibiotics. This study aimed to isolate a bacteriophage to be used as a bactericidal agent against Salmonella in milk and dairy products. Here, phage ZCSE6 has been isolated from raw milk sample sand molecularly and chemically characterized. At different multiplicities of infection (MOIs) of 0.1, 0.01, and 0.001, the phage–Salmonella interaction was studied for 6 h at 37 °C and 24 h at 8 °C. In addition, ZCSE6 was tested against Salmonella contamination in milk to examine its lytic activity for 3 h at 37 °C. The results showed that ZCSE6 has a small genome size (<48.5 kbp) and belongs to the Siphovirus family. Phage ZCSE6 revealed a high thermal and pH stability at various conditions that mimic milk manufacturing and supply chain conditions. It also demonstrated a significant reduction in Salmonella concentration in media at various MOIs, with higher bacterial eradication at higher MOI. Moreover, it significantly reduced Salmonella growth (MOI 1) in milk, manifesting a 1000-fold decrease in bacteria concentration following 3 h incubation at 37 °C. The results highlighted the strong ability of ZCSE6 to kill Salmonella and control its growth in milk. Thus, ZCSE6 is recommended as a biocontrol agent in milk to limit bacterial growth and increase the milk shelf-life.

Actual Challenges, Risks and Security Safety

2020 ◽  
Vol 1 (1) ◽  
pp. 65-83
Author(s):  
Božidar Forca ◽  
Dragoljub Sekulović ◽  
Igor Vukonjanski
Keyword(s):  
National Security ◽  
Modern World ◽  
Security Strategy ◽  
Theoretical Understanding ◽  
National Security Strategy ◽  
Security Challenges ◽  
Wide Range ◽  
The Subject ◽  
Almost All ◽  
The Relationship

Security is one of the most common terms in the modern world. This statement is supported by the fact that the term security is used in a wide range of areas. The subject of this paper is national security and the challenges, risks and threats to that security in contemporary international relations. The purpose of the work is twofold. First, to show the diversity of theoretical understanding of the term challenge, risk and threat by various authors. On the other hand, the overriding goal is to analyze the relationship to the challenges, risks and threats in different countries. When it comes to national security, challenges, risks and threats, most often, are identified in a document called the national security strategy. This document, as one of the highest in the hierarchy of political acts of every state, when it comes to security, is passed by almost all modern states of the world. The analysis of numerous national security strategies has revealed that it is possible to identify: 1) the challenges, risks and threats that appear in all strategies, 2) the challenges, risks and threats of security that appear in most strategies, and 3) the challenges, risks and threats of security which are country specific.

What Kind of Friction Model Is Needed to Predict Brake Squeal?

2012 ◽  
Author(s):  
Tore Butlin ◽  
Jim Woodhouse
Keyword(s):  
Large Scale ◽  
Dynamic Properties ◽  
Theoretical Work ◽  
Friction Model ◽  
Coupled Systems ◽  
Brake Squeal ◽  
Model Framework ◽  
Wide Range ◽  
Pin On Disc ◽  
Almost All

Predictive models of friction-induced vibration have proved elusive despite decades of research. There are many mechanisms that can cause brake squeal; friction coupled systems can be highly sensitive to small perturbations; and the dynamic properties of friction at the contact zone seem to be poorly understood. This paper describes experimental and theoretical work aimed at identifying the key ingredients of a predictive model. A large-scale experiment was carried out to identify squeal initiations using a pin-on-disc test rig: approximately 30,000 squeal initiations were recorded, covering a very wide range of frequencies. The theoretical model allows for completely general linear systems coupled at a single sliding point by friction: squeal is predicted using a linearised stability analysis. Results will be presented that show that almost all observed squeal events can be predicted within this model framework, but that some subsets require innovative friction modelling: predictions are highly dependent on the particular choice of friction model and its associated parameters.

scholarly journals Two Populations of Glucocorticoid Receptor-Binding Sites in the Male Rat Hippocampal Genome

Endocrinology ◽  
2013 ◽  
Vol 154 (5) ◽  
pp. 1832-1844 ◽  
Author(s):  
J. Annelies E. Polman ◽  
E. Ronald de Kloet ◽  
Nicole A. Datson
Keyword(s):  
Receptor Binding ◽  
Binding Sites ◽  
Glucocorticoid Receptors ◽  
Full Range ◽  
Male Rat ◽  
Motif Analysis ◽  
Wide Range ◽  
Neuronal Processes ◽  
Almost All

Abstract In the present study, genomic binding sites of glucocorticoid receptors (GR) were identified in vivo in the rat hippocampus applying chromatin immunoprecipitation followed by next-generation sequencing. We identified 2470 significant GR-binding sites (GBS) and were able to confirm GR binding to a random selection of these GBS covering a wide range of P values. Analysis of the genomic distribution of the significant GBS revealed a high prevalence of intragenic GBS. Gene ontology clusters involved in neuronal plasticity and other essential neuronal processes were overrepresented among the genes harboring a GBS or located in the vicinity of a GBS. Male adrenalectomized rats were challenged with increasing doses of the GR agonist corticosterone (CORT) ranging from 3 to 3000 μg/kg, resulting in clear differences in the GR-binding profile to individual GBS. Two groups of GBS could be distinguished: a low-CORT group that displayed GR binding across the full range of CORT concentrations, and a second high-CORT group that displayed significant GR binding only after administering the highest concentration of CORT. All validated GBS, in both the low-CORT and high-CORT groups, displayed mineralocorticoid receptor binding, which remained relatively constant from 30 μg/kg CORT upward. Motif analysis revealed that almost all GBS contained a glucocorticoid response element resembling the consensus motif in literature. In addition, motifs corresponding with new potential GR-interacting proteins were identified, such as zinc finger and BTB domain containing 3 (Zbtb3) and CUP (CG11181 gene product from transcript CG11181-RB), which may be involved in GR-dependent transactivation and transrepression, respectively. In conclusion, our results highlight the existence of 2 populations of GBS in the rat hippocampal genome.

scholarly journals DNA methylation-based sex classifier to predict sex and identify sex chromosome aneuploidy

2020 ◽  
Author(s):  
Yucheng Wang ◽  
Eilis Hannon ◽  
Olivia A Grant ◽  
Tyler J Gorrie-Stone ◽  
Meena Kumari ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Sex Chromosome ◽  
Klinefelter Syndrome ◽  
Association Studies ◽  
Gene Expression Omnibus ◽  
Sex Chromosome Aneuploidy ◽  
Chromosome Aneuploidy ◽  
Wide Range ◽  
Almost All ◽  
Methylation Patterns

AbstractSex is an important covariate of epigenome-wide association studies due to its strong influence on DNA methylation patterns across numerous genomic positions. Nevertheless, many samples on the Gene Expression Omnibus (GEO) frequently lack a sex annotation or are incorrectly labelled. Considering the influence that sex imposes on DNA methylation patterns, it is necessary to ensure that methods for filtering poor samples and checking of sex assignment are accurate and widely applicable. In this paper, we presented a novel method to predict sex using only DNA methylation density signals, which can be readily applied to almost all DNA methylation datasets of different formats (raw IDATs or text files with only density signals) uploaded to GEO. We identified 4345 significantly (p < 0.01) sex-associated CpG sites present on both 450K and EPIC arrays, and constructed a sex classifier based on the two first components of PCAs from the two sex chromosomes. The proposed method is constructed using whole blood samples and exhibits good performance across a wide range of tissues. We further demonstrated that our method can be used to identify samples with sex chromosome aneuploidy, this function is validated by five Turner syndrome cases and one Klinefelter syndrome case. The proposed method has been integrated into the wateRmelon Bioconductor package.

scholarly journals The issue of nosocomial infection caused by Klebsiella pneumoniae blaNDM-type

2020 ◽  
Vol 15 (2) ◽  
pp. 124-133
Author(s):  
Olga Mironenko ◽  
◽  
Victoria Selnitseva ◽  
Lidia Soprun ◽  
Elena Shmushkevich ◽  
...  
Keyword(s):  
Klebsiella Pneumoniae ◽  
Nosocomial Infection ◽  
Molecular Genetic ◽  
Mechanisms Of Resistance ◽  
Infectious Process ◽  
Saint Petersburg ◽  
Microbiological Study ◽  
Wide Range ◽  
Almost All ◽  
Emergence Of Resistance

The article presents information about circulating isolates Klebsiella pneumoniae in a hospital megapolis with properties of hypervirulence and simultaneous multiresistance. The resulting K. pneumonia isolates are of particular importance due to the emergence of resistance to almost all β-lactams due to the presence of carbapenemase metal-β-lactamase. Furthermore, the isolated strains producing carbapenemases possess mechanisms of resistance to a wide range of antimicrobial preparations, and the types of infectious process caused by carbapenemazo-producing enterobacteries are characterized by a high lethality level. Microbiological, biochemical, biophysical, molecular-genetic, biological, bioinformational and statistical methods of research were used in the work. A prospective method was used to identify the source of the infections. In the first stage, a microbiological study was carried out on biomaterials obtained from patients treated in a hospital in Saint Petersburg. After a microbiological study, 52 isolates of K. pneumoniae were obtained, 53.8 % of isolates had a hypermucoid phenotype and 98 % had carbapenemases:blaNDM type — 49 (92 %), blaNDM+OXA-48-like — 3 (8 %). Isolates with two new phenotypes have been isolated (no. 2511 and no. 2512). Isolates of no. 2512 LD50 had 10*2 BAC/ml, and plasmids such as Incfib(Mar), Inchi1b, and Incr were also found, with Incr-A plasmid emitted encoding resistance to fluoroquinolone: aac(6’)-Ib-cr and to β-lactam antibiotics: blaTEM-1B. The described data confirm the opinions of the researchers about the possible formation of a new “super pathogen” — instantaneously hypervirulent and plural resistant strain of K. pneumoniae.

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