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Cosmetic products and women's health
No full textGünümüzde kozmetik ürünler, çok çeşitli etkileri nedeniyle modern toplumun vazgeçilmez bir ürünü olarak karşımıza çıkmaktadır. Genellikle içeriğindeki kimyasal maddelere hiç bakılmadan kullanılan ve hedef kitlesi çoğunlukla kadınlar olan bu ürünler, bilinçsiz kullanıldığında sağlığı olumsuz etkilemektedir. Bu makalede, ilaçlar gibi yasal düzenlemeleri olması gereken kozmetik ürünlerin içeriğindeki bazı kimyasal maddelerin kadın sağlığına etkileri güncel araştırmalarla ele alınmış ve kadınlar başta olmak üzere toplumun kozmetik ürünler konusundaki farkındalığını artırmak amaçlanmıştır. / Due to their various effects, today cosmetic products are indispensable products of modern society. These products which are generally used without considering chemical material in their content and whose target group are generally women influence health negatively when they are used unconsciously. In this paper, the effect of chemical materials in the content of cosmetic products which should be used with legal arrangements on women health was analyzed through recent studies and it was aimed to analyze awareness of society, especially women, about cosmetic products
A young male patient presented with dyspnea, cough, and lilateral pulmonary infiltrations: what is your siagnosis?
No full textA broken gauge approach to gravitational mass and charge
No full textWe argue that a spontaneous breakdown of local Weyl invariance offers a mechanism in which gravitational interactions contribute to the generation of particle masses and their electric charge. The theory is formulated in terms of a spacetime geometry whose natural connection has both dynamic torsion and non-metricity. Its structure illuminates the role of dynamic scales used to determine measurable aspects of particle interactions and it predicts an additional neutral vector boson with electroweak properties. © SISSA/ISAS 2002
Hydrogen gas sensing using palladium-coated microdisk microresonators
No full textAn SU-8 polymer microdisk resonator coated with a palladium (Pd) layer and coupled to a single-mode optical waveguide is used to as a hydrogen (H-2) gas sensor. In the presence of H2 a red shift is observed in the spectral positions of the microdisk whispering gallery modes (WGMs) due to the expansion in the Pd lattice. H-2 concentrations below the flammable limit (4%) down to 0.3% could be detected in nitrogen atmosphere at room temperature. For H-2 concentrations between 0.3 1%, WGM spectral positions shifted linearly with H-2 concentration at a rate of 32 pm/%H-2. Average response time of the devices was measured to be 50 s for 1% H-2. The proposed device concept can also be used to detect different chemical gases by using appropriate sensing layers
Metamaterial based cloaking with sparse distribution of spiral resonators
No full textWe investigate the application of a metamaterial that is formed by the sparse distribution of spiral resonators as an optical transformation medium is in order to achieve electromagnetic cloaking. The well-known Clausius-Mossotti formula relates the microscopic polarizability of a single resonant particle to the macroscopic permittivity and permeability of the effective medium. By virtue of transformation optics, the permittivity and permeability of the medium, in turn, can be designed according to a coordinate transformation that maps a certain region of space to its surrounding. As a result, the mapped region can be cloaked from electromagnetic waves. In this study, the spirals are optimized to exhibit equal permittivity and permeability response so that the cloak formed by these spirals will work for both the TE and TM polarizations. An experimental setup is developed to visualize the steady state propagation of electromagnetic waves within a parallel plate waveguide including the cloaking structure. The measured and simulated electromagnetic field image indicates that the forward scattering of a metal cylinder is significantly reduced when placed within the cloak
Survival probability in a one-dimensional quantum walk on a trapped lattice
No full textThe dynamics of the survival probability of quantum walkers on a one-dimensional lattice with random distribution of absorbing immobile traps is investigated. The survival probability of quantum walkers is compared with that of classical walkers. It is shown that the time dependence of the survival probability of quantum walkers has a piecewise stretched exponential character depending on the density of traps in numerical and analytical observations. The crossover between the quantum analogues of the Rosenstock and Donsker-Varadhan behavior is identified
Phase noise in oscillators as differential-algebraic systems with colored noise sources
No full textOscillators are key components of many kinds of systems, particularly electronic and opto-electronic systems. Undesired perturbations, i.e. noise, in practical systems adversely affect the spectral and timing properties of the signals generated by oscillators resulting in phase noise and timing jitter, which are key performance limiting factors, being major contributors to bit-error-rate (BER) of RF and possibly optical communication systems, and creating synchronization problems in clocked and sampled-data electronic systems. In this paper. we review our work on the theory and numerical methods for nonlinear perturbation and noise analysis of oscillators described by a system of differential-algebraic equations (DAEs) with white and colored noise sources. The bulk of the work reviewed in this paper first appeared in [1], then in [2] and [3]. Prior to the work mentioned above, we developed a theory and numerical methods for nonlinear perturbation and noise analysis of oscillators described by a system of ordinary differential equations (ODEs) with white noise sources only [4, 5]. In this paper, we also discuss some open problems and issues in the modeling and analysis of phase noise both in free running oscillators and in phase/injection-locked ones
DICER governs characteristics of glioma stem cells and the resulting tumors in xenograft mouse models of glioblastoma
No full textThe RNAse III endonuclease DICER is a key regulator of microRNA (miRNA) biogenesis and is frequently decreased in a variety of malignancies. We characterized the role of DICER in glioblastoma (GB), specifically demonstrating its effects on the ability of glioma stem-like cells (GSCs) to form tumors in a mouse model of GB. DICER silencing in GSCs reduced their stem cell characteristics, while tumors arising from these cells were more aggressive, larger in volume, and displayed a higher proliferation index and lineage differentiation. The resulting tumors, however, were more sensitive to radiation treatment. Our results demonstrate that DICER silencing enhances the tumorigenic potential of GSCs, providing a platform for analysis of specific relevant miRNAs and development of potentially novel therapies against GB
An empirical profile of VLF triggered emissions
No full textThe Siple Transmitter Experiment operated from 1973 to 1988 and generated a wealth of observations of nonlinear wave-particle interactions including extensive recordings of triggered emissions generated by VLF signals injected into the magnetosphere from the transmitter at Siple Station, Antarctica. Due to their complex appearance and immensely varied behavior, triggered emissions remain poorly described and understood. This work provides a comprehensive statistical description of observed triggered emissions and establishes statistical bounds on triggered emission type (fallers, risers, and positive and negative hooks) and behavior (frequency changes between 1kHz and 2.5kHz with initial sweep rates between -2.5kHz/s and 2.5kHz/s, with risers undergoing a median frequency change of 556Hz and fallers a median frequency change of -198Hz). The statistical study also reveals an apparent dependence of the triggered emission behavior on the transmitted signal itself. Long tones and rising ramps generate more risers and positive hooks, while short tones and falling ramps produce more fallers and negative hooks. Triggered emissions also appear to favorably initiate with sweep rates similar to that of the triggering element, with the 1kHz/s rising ramps triggering initial risers with a median sweep rate of 1.03kHz/s and -1kHz/s triggering initial fallers with a median sweep rate of -0.73kHz/s. These results improve observations of wave modification resulting from wave-particle interactions in the radiation belts and can be used to validate numerical simulations of triggered emissions
The Turkey-EU-US triangle in perspective: transformation or continuity?
No full textThis article examines the delicate dynamics of the triangle of Turkey-EU-US relations. While acknowledging the role of the United States in promoting close links between Turkey and the EU, this study underlines the limits of American influence on EU decision-making on issues concerning "deep integration." In this context, the future of this triangular relation depends on the interplay of contending forces in Turkey's domestic political arena as well as the dynamics of trans-Atlantic relations in the international scene