A model that integrates eye velocity commands to keep track of smooth eye displacements.

Past results have reported conflicting findings on the oculomotor system's ability to keep track of smooth eye movements in darkness. Whereas some results indicate that saccades cannot compensate for smooth eye displacements, others report that memory-guided saccades during smooth pursuit are spatially correct. Recently, it was shown that the amount of time before the saccade made a difference: short-latency saccades were retinotopically coded, whereas long-latency saccades were spatially coded. Here, we propose a model of the saccadic system that can explain the available experimental data. The novel part of this model consists of a delayed integration of efferent smooth eye velocity commands. Two alternative physiologically realistic neural mechanisms for this integration stage are proposed. Model simulations accurately reproduced prior findings. Thus, this model reconciles the earlier contradictory reports from the literature about compensation for smooth eye movements before saccades because it involves a slow integration process

Chemical Methods for Detection of Allergens and Skin Exposure

Many allergens are widely used in both consumer and occupational products. In many cases, it is difficult to know all the ingredients of a product since most products are not sufficiently labelled. To diagnose and prevent allergic contact dermatitis, the demonstration of allergens in the products from the patient’s environment is important. Chemical analysis of a product can make it possible to demonstrate the presence or absence of known allergens. Simple spot tests or documented analytical methods such as thin-layer chromatography (TLC), high-performance liquid chromatography (HPLC), gas chromatography (GC), atomic absorption spectrophotometry (AAS), and inductively coupled plasma-mass spectrometry (ICP-MS) can be used. Moreover, with chemical methods, the purity of a substance can be checked and new allergens can be isolated and identified. Advanced methods such as mass spectrometry (MS), nuclear magnetic resonance spectroscopy (NMR), and infrared spectrophotometry (IR) are often required to identify isolated allergens