In liquid chromatography, baseline noise should be as low as possible to provide an optimum signal-to-noise ratio and to enable reliable integration of peaks at trace level. Baseline noise has different sources. One source is the detector, and another is the mixing performance of the pump, which is especially important if, for example, trifluoroacetic acid (TFA) is used as modifier in the mobil...

Contact urticaria is defined as a wheal-and-flare reaction that occurs after epicutaneous contact with a causative agent (1). Contact urticaria usually appears within minutes after contact with the causative substances, including chemicals, animal products, antibiotics and cosmetics. We report here a case of contact urticaria resulting from exposure to a disinfectant liquid spray containing eth...

In this paper, we propose two new construction methods for quaternary Hadamard matrices. By the first method, which is applicable for any positive integer n, we are able to construct a quaternary Hadamard matrix of order 2 from a binary sequence with ideal autocorrelation. The second method also gives us a quaternary Hadamard matrix of order 2 from a binary extended sequence of period 2 − 1, wh...

Data from 10,126 earthquakes that occurred in the southern California region between 1934 and 1963 have been synthesized in the attempt to understand better their relationship to regional geologic structure, which is here dominated by a system of faults related mainly to the San Andreas system. Most of these faults have been considered "active" from physiographic evidence, but both geologic and...

Abstract The southern extreme location and the natural landscapes, highly modelled by glaciers during Quaternary period, give Tierra del Fuego a unique opportunity to attract visitors worldwide. Its glacial landforms are geodiversity resources that witness global climate changes as processes. Therefore, this study aims highlight different considering their geodidactic potential for educational ...

Global climate fluctuations have significantly influenced the distribution and abundance of biodiversity. During unfavorable glacial periods, many species experienced range contraction and fragmentation, expanding again during interglacials. An understanding of the evolutionary consequences of both historical and ongoing climate changes requires knowledge of the temporal dynamics of population ...

Traffic problems are the most prominent urban dilemmas, especially during recent years, since the capacity of old traffic arteries don’t meet the increasing volume of population and vehicles, therefore, adopting some measures in order to enhance the capacity of existing roads has been placed on the agenda of urban managers. Changing the existing intersections to over changes is one of these met...