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This work deals with solving continuous-time nonlinear complementarity problems defined on two types of nonempty closed convex cones: a polyhedral cone (positive octant) and a second-order cone. Theoretical results that establish a relationship between such problems and the variational inequalities problem are presented. We show that global minimizers of an unconstrained continuous-time programming problem are solutions to the continuous-time nonlinear complementarity problem. Moreover, a relation is set up so that a stationary point of an unconstrained continuous-time programming problem, in which the objective function involves the Fischer-Burmeister function, is a solution for the continuous-time complementarity problem. To guarantee the validity of the K.K.T. conditions for some auxiliary continuous-time problems which appear during the theoretical development, we use the linear independence constraint qualification. These constraint qualification are posed in the continuous-time context and appeared in the literature recently. In order to exemplify the developed theory, some simple examples are presented throughout the text.

Abstract The fundamental vacuum state of quantum fields, related to Minkowski space, produces divergent fluctuations that must be suppressed in order to bring reality to the description of physical systems. As a consequence, negative vacuum expectation values of classically positive-defined quantities can appear. This has been addressed in the literature as subvacuum phenomenon. Here it is investigated how a scalar charged test particle is affected by the vacuum fluctuations of a massive scalar field in D + 1 spacetime when the background evolves from empty space to a thermal bath, and also when a perfectly reflecting boundary is included. It is shown that when the particle is brought into a thermal bath it gains an amount of energy by means of positive dispersions of its velocity components. The magnitude of this effect is dependent on the temperature and also on the field mass. However, when a reflecting wall is inserted, dispersions can be positive or negative, showing that subvacuum effect happens even in a finite temperature environment. Furthermore, a remarkable result is that temperature can even improve negative velocity fluctuations. The magnitude of the residual effects depends on the switching interval of time the system takes to evolve between two states.

BackgroundChildhood asthma is associated with emotional and behavioural problems. The prevalence and factors associated with psychological problems in childhood asthma have not been studied in Sri Lanka. AimsThe aim of this study was to describe the prevalence and factors associated with development of emotional and behavioural problems among children with asthma, presenting to outpatient follow up clinics. MethodsThis was a hospital based cross sectional descriptive study using systematic random sampling (n=250). The parents completed the Strengths and Difficulties Questionnaire (Sinhala version) and children with borderline or abnormal scores were assessed further using a structured interview, based on the International Classification for Disease-10 research criteria. ResultsThe mean age of participants was 8.1 years and 141 (56.4%) were males. The mean duration of asthma and age at diagnosis was 4.4 years and 3.6 years respectively. In 62% of participants, the asthma was well controlled. The prevalence of mental health problems was 8%. Borderline or abnormal scores in at least one scale of the SDQ was found in 18.4%, and 2.8% had abnormal or borderline impact scores. The level of asthma control was significantly associated with emotional problems score (OR 8.23, p=0.41). ConclusionsThe prevalence of mental health problems among children with asthma was comparable to the general population. Asthma control was significantly associated with emotional problems and this carries implications for management.

Abstract Quantum vacuum fluctuations of the electromagnetic field in empty space seem not to produce observable effects over the motion of a charged test particle. However, when a change in the background vacuum state is implemented, as for instance when a conducting boundary is introduced, dispersions of the particle velocity may occur. As a consequence, besides the existence of classical effects due to the interaction between particle and boundary, there will be a quantum contribution to the motion of the particle whose magnitude depends on how fast the transition between the different vacuum states occurs. Here this issue is revisited and a smooth transition with a controllable switching time between the vacuum states of the system is implemented. Dispersions of the particle velocity in both, zero and finite temperature regimes are examined. More than just generalizing previous results for specific configurations, new effects are unveiled. Particularly, it is shown that the well known vacuum dominance reported to occur arbitrarily near the wall is a consequence of assumed idealizations. The use of a controllable switching enables us to conclude that thermal effects can be as important as, or even stronger than, vacuum effects arbitrarily near the wall. Additionally, the residual effect predicted to occur in the late time regime was here shown to be linked to the duration of the transition. In this sense, such effect is understood to be a sort of particle energy exchanging due to the vacuum state transition. Furthermore, in certain arrangements a sort of cooling effect over the motion of the particle can occur, i.e., the kinetic energy of the particle is lessen by a certain amount due to subvacuum quantum fluctuations.

Abstract The contribution from quantum vacuum fluctuations of a real massless scalar field to the motion of a test particle that interacts with the field in the presence of a perfectly reflecting flat boundary is here investigated. There is no quantum induced dispersions on the motion of the particle when it is alone in the empty space. However, when a reflecting wall is introduced, dispersions occur with magnitude dependent on how fast the system evolves between the two scenarios. A possible way of implementing this process would be by means of an idealized sudden switching, for which the transition occurs instantaneously. Although the sudden process is a simple and mathematically convenient idealization it brings some divergences to the results, particularly at a time corresponding to a round trip of a light signal between the particle and the wall. It is shown that the use of smooth switching functions, besides regularizing such divergences, enables us to better understand the behavior of the quantum dispersions induced on the motion of the particle. Furthermore, the action of modifying the vacuum state of the system leads to a change in the particle energy that depends on how fast the transition between these states is implemented. Possible implications of these results to the similar case of an electric charge near a perfectly conducting wall are discussed.

Este trabalho trata do emprego do ciclometalado [Pd(dmba) (NCO)(PPh 3 )] (dmba = N,N- dimetilbenzilamina; PPh 3 = trifenilfosfina) em processos catalíticos em fase homogênea, envolvendo a reação entre p-toluidina e p-nitrotolueno, produzindo N,N’-bis(4-metilfenil)uréia. A reação foi realizada a 140 0 C, sob pressão inicial de CO de 60 bar. Empregou-se também o mesmo composto em reações de carbonilação na presença dos álcoois metílico e etílico, obtendo-se os alcoxicarbonil complexos [Pd(NCO)(CO 2 R)(PPh 3 ) 2 ] (R=Me ou Et). Constatou-se que o emprego do [Pd(dmba)(NCO)(PPh 3 )] nos referidos processos, propiciou a formação dos produtos com bons rendimentos.

In the Netherlands, the implementation of mandatory procedures in which prospective students do a final check on their initial higher education program choice (so-called matching procedures), were introduced to improve student-program fit. We argue that prospective students who lack feelings of fit with the program during these matching procedures are less likely to finalise their enrolment. Using data of 13 programs at four Dutch universities, the association between various matching procedures and finalising enrolment, and finalising enrolment before and after the implementation of matching were examined. Enrolment rates were lower in programs with more intensive matching procedures and higher in pre-matching cohorts than in matching cohorts, indicating the potential value of pre-enrolment fit checks. In conclusion, this study gives indications that it can be worthwhile to invest in guiding prospective students in their program choice by obliging them to test their fit with the program through intensive matching procedures.

The geneses, treatment and outcome of pica remains the subject of much debate. Data regarding pica in adults and in schizophrenia is limited. We present the case of a forty-year old male who presented with subacute intestinal obstruction. Having met the diagnostic criteria for schizophrenia, he subsequently developed symptoms which enabled a diagnosis of pica. Initially the pica symptoms were as a response to the command hallucinations, but later persisted in the absence of hallucinations. Pica can be potentially life-threatening, depending on the substance ingested and the complications that follow, as was the case in this patient. Risperidone, olanzapine or electro convulsive therapy did not have any impact on his symptoms of pica. Clozapine was commenced and a dramatic response was observed, with the pica symptoms completely resolving within 10 days – thus revealing a new facet to the already versatile therapeutic effects of clozapine.

Flag leaves play an important role in synthesis and translocation of photoassimilates in the rice plant, affecting grain yield; similarly they were believed to be a major source of remobilized minerals for the seeds. At the same time, the seed's sink strength plays an important role in dry matter accumulation. To investigate the relative contribution of rice flag leaves and seed sink strength to seed mineral accumulation, field experiments were conducted to evaluate the effect of flag leaf or half-seed removal on seed Fe, Mn and Zn concentration and content. Flag leaf or 50% of the seeds were removed at anthesis. Seed Fe, Mn and Zn accumulation were not affected by flag leaf or second leaf removal. Plants with only half of the seeds showed higher Fe and Zn seed concentrations, but similar Mn concentrations. It is concluded that the flag leaf is not necessary for metal remobilization to the seeds and that seed sink strength and seed number have different roles in Fe/Zn and Mn seed concentrations.

O uso de plantas medicinais tem aumentado bastante na população mundial. O objetivo desta pesquisa é avaliar os efeitos do extrato aquoso das folhas da Hyptis pectinata, popularmente conhecida como "sambacaitá" ou "canudinho", sobre a regeneração hepática após hepatectomia parcial de 70%. Foram utilizados 24 ratos, divididos em 4 grupos: grupo OS, em que se realizou operação simulada e aplicação oral de água destilada por 4 dias; grupo OSD200, também submetido à laparotomia com manipulação do fígado e aplicação de 200 mg de extrato/Kg de animal durante o mesmo período; grupo HP, hepatectomizado a 70% após 4 dias de aplicação por via oral de água destilada; e grupo HPD200, hepatectomizado a 70% após 4 dias de administração de 200 mg extrato/Kg de animal. Foram dosadas fosfatase alcalina, bilirrubina total e as aminotransferases e estudou-se o estado III da função mitocondrial. O grupo OSD200, quando comparado ao OS, apresentou redução significativa da fosfatase alcalina. O grupo HPD200, em comparação ao HP, teve redução estatisticamente significativa no nível da AST e do estado III da função mitocondrial.The use of medicinal plants has strongly increased by the world population. The objetive of this study is to assess the effects of the aqueous extract of Hyptis pectinata leaves, popularly known as "sambacaitá" or "canudinho", on liver regeneration after 70% partial hepatectomy. Twenty four rats were divided into 4 groups: group OS, submitted to sham operation and oral administration of distilled water during 4 days; group OSD200, also submitted to sham operation and ingestion of 200 mg of extract/Kg of animal for the same period of time; group HP, which underwent 70% hepatectomy after 4 days of distilled water administration; and group HPD200, which underwent 70% hepatectomy after 4 days of oral administration of 200 mg of extract/Kg of animal. Alkaline phosphatase, total bilirubin and the serum level of aminotransferases were measured and state III of mitochondrial respiratory activity was assessed. Group OSD200, when compared to OS, presented significant decrease of alcaline fosfatase. Group HPD200, when compared to HP, showed statistically significant decrease of AST level and state III respiratory process.