Diagnostic focus on the child with myoclonic seizures in isolation or associated with other types of seizures

Myoclonus may be observed in children with mild or severe epileptic syndromes. Both types are seen at characteristic ages, together with other factors: aetiology, family history, hereditary pattern, effect on psychomotor development and EEG-EMG findings. In children with progressive or degenerative encephalopathies and myoclonus, better known as progressive myoclonic epilepsy, there are also specific clinical data, together with biological and genetic markers which permit identification. The most specific clinical characteristics of each of these clinical pictures are described, as are the complementary tests which permit confirmation of these diagnoses.     

A mixed integer programming approach to multi-skilled workforce scheduling

The potential benefits of using human resources efficiently in the service sector constitute an incentive for decision makers in this industry to intelligently manage the work shifts of their employees, especially those dealing directly with customers. In the long term, they should attempt to find the right balance between employing as few labor resources as possible and keeping a high level of service. In the short run (e.g., 1 week), however, contracted staff levels cannot be adjusted, and management efforts thus focus on the efficient assignment of shifts and activities to each employee. This article proposes a mixed integer program model that solves the short-term multi-skilled workforce tour scheduling problem, enabling decision makers to simultaneously design workers’ shifts and days off, assign activities to shifts and assign those to employees so as to maximize and balance coverage of a firm’s demand for on-duty staff across multiple activities. Our model is simple enough to be solved with a commercial MIP solver calibrated by default without recurring to complex methodologies, such as extended reformulations and exact and/or heuristic column generation subroutines. A wide computational testing over 1000 randomly generated instances suggests that the model’s solution times are compatible with daily use and that multi-skilling is a significant source of labor flexibility to improve coverage of labor requirements, in particular when such requirements are negatively correlated and part-time workers are a scarce resource.     

An optimization algorithm for multimodal functions inspired by collective animal behavior

Interest in multimodal function optimization is expanding rapidly as real-world optimization problems often demand locating multiple optima within a search space. This article presents a new multimodal optimization algorithm named as the collective animal behavior. Animal groups, such as schools of fish, flocks of birds, swarms of locusts, and herds of wildebeest, exhibit a variety of behaviors including swarming about a food source, milling around a central location, or migrating over large distances in aligned groups. These collective behaviors are often advantageous to groups, allowing them to increase their harvesting efficiency to follow better migration routes, to improve their aerodynamic, and to avoid predation. In the proposed algorithm, searcher agents are a group of animals which interact with each other based on the biologic laws of collective motion. Experimental results demonstrate that the proposed algorithm is capable of finding global and local optima of benchmark multimodal optimization problems with a higher efficiency in comparison with other methods reported in the literature.     

Al–Ti powder produced through mechanical alloying for different times

A powder mixture of aluminum, 10 wt% titanium, and 1.5 wt% of a wax acting as process control agent (PCA), has been attrition-milled for 2–20 h. Titanium powder had been previously ground to a lower particle size to make it similar to the as-received aluminum particle size. The overall aim of this work was to achieve a metastable titanium solution in the aluminum matrix. Changes with milling time of particle size and shape, microstructure, hardness and other powder characteristics have been studied. Given the used experimental-conditions, a process time of 10 h has been selected for the mechanical alloying (MA) of Al–10Ti powder, attaining a compromise between uniform microstructure development and a not so long processing time. At this milling time aluminum dissolves about 9 wt% Ti, increasing its Vickers microhardness (202 VH₂₀) more than 10 times with reference to the starting Al powder (20 VH₂₀). Milled particle size is smaller than the starting one (17 vs. 44 μm). Increasing milling for longer times, up to 20 h, does not produce important changes in powders structure.     

The behaviour of highly over-stoichiometric LaNi5 Mn2 alloy as negative electrode for Ni/MH batteries

Key electrochemical properties of highly over-stoichiometric LaNi₅Mn₂ alloy with CaCu₅-type structure have been measured and compared with those of stoichiometric LaNi₄Mn alloy. LaNi₅Mn₂ is obtained by mechanical alloying of two-phase La(Ni,Mn)₅+(Ni,Mn) alloy previously produced by induction melting. The as-milled alloy was thermally annealed at 450°C for one hour to crystallise milling-induced amorphous phase. As derived from DSC and XRD measurements, further annealing at 550°C produces segregation of minor NiMn-phase (21 wt%), which leaves stoichiometric LaNi₄Mn alloy (79 wt%) as a major phase. Electrochemical cycle-life and potential equilibrium measurements for both LaNi₅Mn₂ and LaNi₄Mn alloys show that the over-stoichiometric alloy has much lower discharge capacity than the stoichiometric one (135 mAh/g and 260 mAh/g, respectively). Conversely, the over-stoichiometric alloy exhibits much better cycle-life than the stoichiometric one (5% and 25% decay capacity after 55 cycles, respectively). These results demonstrate that stoichiometry is an effective parameter for tuning the discharge capacity and cycle-life of LaNi_5+x -type electrodes to the performances required by a particular application.     

Thermodynamics and reaction pathways of hydrogen sorption in Mg6(Pd,TM) (TM = Ag,Cu and Ni) pseudo-binary compounds

Mg₆(Pd,TM) (TM = Ag, Cu and Ni) pseudo-binary compounds have been synthesized at the TM solubility limit to determine the influence of TM on the thermodynamics and reaction pathways of the Mg₆Pd–H system. All compounds exhibit a two-plateau pressure behaviour, being the value of the high plateau pressure well above that of the Mg/MgH₂ system. Such destabilization is explained by the formation of different Mg–(Pd,TM) intermetallics and/or Mg₂NiH₄ hydride phases during the hydrogenation reaction. The formation of these phases not only increases the enthalpy of hydrogenation but also enhances disorder leading to a limited destabilization of the hydrogenated state. This compensation effect is characterized by a linear correlation between enthalpy and entropy terms. In addition, this work also provides the assessment at 623 K of the ternary Mg–Pd–Cu phase diagram in the Mg-rich corner.     

An analysis of the transition proportion for binarization in handwritten historical documents

In this paper, we will present a mathematical analysis of the transition proportion for the normal threshold (NorT) based on the transition method. The transition proportion is a parameter of NorT which plays an important role in the theoretical development of NorT. We will study the mathematical forms of the quadratic equation from which NorT is computed. Through this analysis, we will describe how the transition proportion affects NorT. Then, we will prove that NorT is robust to inaccurate estimations of the transition proportion. Furthermore, our analysis extends to thresholding methods that rely on Bayes rule, and it also gives the mathematical bases for potential applications of the transition proportion as a feature to estimate stroke width and detect regions of interest. In the majority of our experiments, we used a database composed of small images that were extracted from DIBCO 2009 and H-DIBCO 2010 benchmarks. However, we also report evaluations using the original (H-)DIBCO?s benchmarks.     

Preliminary study of the use of spent diatomaceous earth from the brewing industry in clay matrix bricks

In this work the effect of spent diatomaceous earth (SDE), as pore forming or silica carrier, on the properties of clay ceramic bricks was investigated. Mixtures of clay and SDE waste were, compacted, dried and fired at 950°C during 6?h. The technological properties of waste-clay bricks were analysed to evaluate the influence of the waste incorporation. The SDE (1–5?wt-%) addition in the clay matrix causes a reduction between 6 and 12% of the bulk density compared with the control samples (only clay) which implies good insulating characteristics. In addition, the waste incorporation increases the water absorption within the range 4–31% and decreases the compressive strength between 12 and 26%. However, the incorporation of the waste is beneficial as no remarkable changes in the technological properties are observed. These results indicate that the waste has a predominant pore forming effect over a pore filling effect.     

An optimization algorithm inspired by the States of Matter that improves the balance between exploration and exploitation

The ability of an Evolutionary Algorithm (EA) to find a global optimal solution depends on its capacity to find a good rate between exploitation of found-so-far elements and exploration of the search space. Inspired by natural phenomena, researchers have developed many successful evolutionary algorithms which, at original versions, define operators that mimic the way nature solves complex problems, with no actual consideration of the exploration-exploitation balance. In this paper, a novel nature-inspired algorithm called the States of Matter Search (SMS) is introduced. The SMS algorithm is based on the simulation of the states of matter phenomenon. In SMS, individuals emulate molecules which interact to each other by using evolutionary operations which are based on the physical principles of the thermal-energy motion mechanism. The algorithm is devised by considering each state of matter at one different exploration–exploitation ratio. The evolutionary process is divided into three phases which emulate the three states of matter: gas, liquid and solid. In each state, molecules (individuals) exhibit different movement capacities. Beginning from the gas state (pure exploration), the algorithm modifies the intensities of exploration and exploitation until the solid state (pure exploitation) is reached. As a result, the approach can substantially improve the balance between exploration–exploitation, yet preserving the good search capabilities of an evolutionary approach. To illustrate the proficiency and robustness of the proposed algorithm, it is compared to other well-known evolutionary methods including novel variants that incorporate diversity preservation schemes. The comparison examines several standard benchmark functions which are commonly considered within the EA field. Experimental results show that the proposed method achieves a good performance in comparison to its counterparts as a consequence of its better exploration–exploitation balance.