On the characterisation of a Bragg spectrometer with X-rays from an ECR source

Narrow X-ray lines from helium-like argon emitted from a dedicated ECR source have been used to determine the response function of a Bragg crystal spectrometer equipped with large area spherically bent silicon (111) or quartz (10$\bar{1}$) crystals. The measured spectra are compared with simulated ones created by a ray-tracing code based on the expected theoretical crystal's rocking curve and the geometry of the experimental set-up.Comment: Version acceptee (NIM

Effects of Urea, Borax and Ammonium Chloride on Flame Retarding Properties of Cellulosic Ceiling Board

This work involves the impregnation of urea, borax and ammonium chloride solutions prepared in varying concentrations into strips of cellulosic ceiling board. A formulated solution was also made of equal concentration of urea and borax solution and impregnated into strips of cellulosic ceiling board. The treated and blank samples were dried and investigated for ignitability, flame propagation and afterglow time. Urea was found to give a good effect for ignitability after 28.00sec than borax, ammonium chloride and blank after 26.00sec, 25.00sec and 16.80sec respectively. Urea gave a better effect for flame propagation of 0.13x10-2cm/sec than borax, ammonium chloride and blank which has 0.24x10-2cm/sec, 0.28x10-2cm/sec and 1.95x10-2cm/sec respectively and also urea has afterglow time of 0.22x102sec than borax (0.60 x102sec), ammonium chloride (0.70x102sec) and blank (2.25 x102sec). The formulated solution drastically improved the ignitability from 16.80sec (blank) to 34.00sec and zero flame propagation and afterglow time was recorded. With this result, urea was found to give a better retarding effect, hence could be incorporated in cellulosic ceiling board during production. Keywords: Urea, borax, ceiling board, ignitability, flame propagation, afterglow time

Effects of Urea, Borax and Ammonium Chloride on Flame Retarding Properties of Cellulosic Ceiling Board

Abstract This work involves the impregnation of urea, borax and ammonium chloride solutions prepared in varying concentrations into strips of cellulosic ceiling board. A formulated solution was also made of equal concentration of urea and borax solution and impregnated into strips of cellulosic ceiling board. The treated and blank samples were dried and investigated for ignitability, flame propagation and afterglow time. Urea was found to give a good effect for ignitability after 28.00sec than borax, ammonium chloride and blank after 26.00sec, 25.00sec and 16.80sec respectively. Urea gave a better effect for flame propagation of 0.13x10 -2 cm/sec than borax, ammonium chloride and blank which has 0.24x10 -2 cm/sec, 0.28x10 -2 cm/sec and 1.95x10 -2 cm/sec respectively and also urea has afterglow time of 0.22x10 2 sec than borax (0.60 x10 2 sec), ammonium chloride (0.70x10 2 sec) and blank (2.25 x10 2 sec). The formulated solution drastically improved the ignitability from 16.80sec (blank) to 34.00sec and zero flame propagation and afterglow time was recorded. With this result, urea was found to give a better retarding effect, hence could be incorporated in cellulosic ceiling board during production

Angiogenesis in gynecological cancers and the options for anti-angiogenesis therapy.

Angiogenesis is required in cancer, including gynecological cancers, for the growth of primary tumors and secondary metastases. Development of anti-angiogenesis therapy in gynecological cancers and improvement of its efficacy have been a major focus of fundamental and clinical research. However, survival benefits of current anti-angiogenic agents, such as bevacizumab, in patients with gynecological cancer, are modest. Therefore, a better understanding of angiogenesis and the tumor microenvironment in gynecological cancers is urgently needed to develop more effective anti-angiogenic therapies, either or not in combination with other therapeutic approaches. We describe the molecular aspects of (tumor) blood vessel formation and the tumor microenvironment and provide an extensive clinical overview of current anti-angiogenic therapies for gynecological cancers. We discuss the different phenotypes of angiogenic endothelial cells as potential therapeutic targets, strategies aimed at intervention in their metabolism, and approaches targeting their (inflammatory) tumor microenvironment

Molecular-rotation-induced splitting of the binary ridge in the velocity map of sub-eV H+ ions ejected from H2 molecules by ion impact

In studies of ion-induced molecular fragmentation, the challenging measurement of the velocity distribution of fragments emitted below 1-eV kinetic energy is rarely achieved, although most fragments have an energy below this value. Here, we study H+ fragment emission in collisions of 10-keV O+ ions with H2 molecules using a field-free time-of-flight technique developed specifically to detect sub-eV fragments. We find that, in the velocity map, the binary ridge due to direct H+ knockout is split into two parts arising from the rotational motion of the H2 molecule, and that this split scales with rotational velocity. The velocity distribution of the nuclei in the original molecule is determined and the thermally populated J = 1 rotational level is found to be the dominant contributor, although asymmetry in the split indicates projectile-induced rotational transitions between M sub-levels. These rotation effects influence fragment emission probabilities, thus carrying important consequences for the radiation-induced hydrogen loss and H2 dissociation in the atmospheres or exospheres of planets and moons

Oxidative stress in pregnancy and fertility pathologies

Oxidative stress designates the state of imbalance between reactive oxygen species (ROS) production and antioxidant levels. In a healthy placenta, there is an increase in ROS production, due to formation of new tissues and inherent metabolism, but this is balanced by higher levels of antioxidants. However, this balance is lost in some situations, with a consequent increase in oxidative stress levels. Oxidative stress has been implicated in several placental disorders and pregnancy pathologies. The present review intends to summarize what is known about the relationship between oxidative stress and well-known pregnancy disorders

Antineoplastic Drugs as a Potential Risk Factor in Occupational Settings: Mechanisms of Action at the Cell Level, Genotoxic Effects, and Their Detection Using Different Biomarkers

U članku je prikazana osnovna podjela antineoplastičnih lijekova prema mehanizmima djelovanja na razini stanice. Objašnjeni su mehanizmi genotoksičnosti najvažnijih vrsta lijekova koji se primjenjuju u okviru uobičajenih protokola za liječenje zloćudnih novotvorina. Navedena je važeća klasifi kacija antineoplastika prema kancerogenom potencijalu, podaci o mutagenom potencijalu te je prikazana njihova podjela u skladu s anatomsko-terapijsko-kemijskim sustavom klasifi kacije. Sustavno su prikazani najvažniji rezultati svjetskih i hrvatskih istraživanja na populacijama radnika izloženih antineoplasticima, provedenih u razdoblju 1980.-2009. s pomoću četiri najčešće primjenjivane metode: analize izmjena sestrinskih kromatida, analize kromosomskih aberacija, mikronukleus-testa i komet-testa. Objašnjena su osnovna načela navedenih metoda te raspravljene njihove prednosti i nedostaci. Biološki pokazatelji daju važne podatke o individualnoj osjetljivosti profesionalno izloženih ispitanika koji mogu poslužiti unaprjeđenju postojećih uvjeta rada i upravljanju rizicima pri izloženosti genotoksičnim agensima. Na osnovi prednosti i nedostataka citogenetičkih metoda zaključeno je da je mikronukleus-test, koji podjednako uspješno dokazuje klastogene i aneugene učinke, jedna od najboljih metoda dostupnih za otkrivanje štetnih djelovanja antineoplastičnih lijekova koji su u aktivnoj primjeni.This article brings an overview of the mechanisms of action of antineoplastic drugs used in the clinical setting. It also describes the genotoxic potentials of the most important classes of antineoplastic drugs involved in standard chemotherapy protocols. Classifi cation of antineoplastic drugs according to the IARC monographs on the evaluation of carcinogenic risks to humans is accompanied by data on their mutagenicity and the most recent updates in the Anatomical Therapeutic Chemical (ATC) Classifi cation System. We report the main fi ndings of biomonitoring studies that were conducted in exposed healthcare workers all over the world between 1980 and 2009 using four biomarkers: sister chromatid exchanges, chromosome aberrations, micronuclei. and the comet assay. The methods are briefl y explained and their advantages and disadvantages discussed. Biomarkers provide important information on individual genome sensitivity, which eventually might help to improve current working practices and to manage the risks related with exposure to genotoxic agents. Taking into consideration all known advantages and drawbacks of the existing cytogenetic methods, the micronucleus assay, which is able to detect both clastogenic and aneugenic action, is the most suitable biomarker for assessing harmful effects of antineoplastic drugs currently used in health care