A twin study of psychometric intelligence and efficiency of information processing

Intelligence (IQ) can be seen as the efficiency of mental processes or cognition, as can basic information processing (IP) tasks like those used in our ongoing Memory, Attention and Problem Solving (MAPS) study. Measures of IQ and IP are correlated and both have a genetic component, so we are studying how the genetic variance in IQ is related to the genetic variance in IP. We measured intelligence with five subscales of the Multidimensional Aptitude Battery (MAB). The IP tasks included four variants of choice reaction time (CRT) and a visual inspection time (IT). The influence of genetic factors on the variances in each of the IQ, IP, and IT tasks was investigated in 250 identical and nonidentical twin pairs aged 16 years. For a subset of 50 pairs we have test–retest data that allow us to estimate the stability of the measures. MX was used for a multivariate genetic analysis that addresses whether the variance in IQ and IP measures is possibly mediated by common genetic factors. Analyses that show the modeled genetic and environmental influences on these measures of cognitive efficiency will be presented and their relevance to ideas on intelligence will be discussed.

Minimum-order stable recursive filter design via the genetic algorithm approach

In this paper, the minimum-order stable recursive filter design problem is proposed and investigated. This problem is playing an important role in pipeline implementation sin signal processing. Here, the existence of a high-order stable recursive filter is proved theoretically, in which the upper bound for the highest order of stable filters is given. Then the minimum-order stable linear predictor is obtained via solving an optimization problem. In this paper, the popular genetic algorithm approach is adopted since it is a heuristic probabilistic optimization technique and has been widely used in engineering designs. Finally, an illustrative example is sued to show the effectiveness of the proposed algorithm.

The relationship between radiation-induced chemical processes and transverse relaxation times in polymer gel dosimeters

The effects of ionizing radiation in different compositions of polymer gel dosimeters are investigated using FT-Raman spectroscopy and NMR T-2 relaxation times. The dosimeters are manufactured from different concentrations of comonomers (acrylamide and N,N'-methylene-bis-acrylamide) dispersed in different concentrations of an aqueous gelatin matrix. Results are analysed using a model of fast exchange of magnetization between three proton pools. The fraction of protons in each pool is determined using the known chemical composition of the dosimeter and FT-Raman spectroscopy. Based on these results, the physical and chemical processes in interplay in the dosimeters are examined in view of their effect on the changes in T-2 The precipitation of growing macroradicals and the scavenging of free radicals by gelatin are used to explain the rate of polymerization. The model describes the changes in T-2 as a function of the absorbed dose up to 50 Gy for the different compositions. This is expected to aid the theoretical design of new, more efficient dosimeters, since it was demonstrated that the optimum dosimeter (i.e, with the lowest dose resolution) must have a range of relaxation times which match the range of T-2 values which can be determined with the lowest uncertainty using an MRI scanner.

Recombinant human growth hormone, but not insulin-like growth factor-I, enhances central fat loss in postmenopausal women undergoing a diet and exercise program

We examined the effect of recombinant human growth hormone (rhGH) and/or recombinant human insulin-like growth factor-I (rhIGF-I) on regional fat loss in postmenopausal women undergoing a weight loss regimen of diet plus exercise. Twenty-seven women aged 59-79 years, 20-40% above ideal body weight, completed a 12-week program consisting of resistance training 2 days/week and walking 3 days/week, while consuming a diet that was 500 kcal/day less than that required for weight maintenance, Participants were randomly assigned in a double-blind fashion to receive rhGH (0.025 mg/kg BW/day: n=7), rhIGF-I (0.015 mg/kg BW/day: n=7), rhGH + rhIGF-I (n = 6), or placebo (PL: n = 7). Regional and whole body fat mass were determined by dual X-ray absorptiometry. Body fat distribution was assessed by the ratios of trunk fat-to-limb fat (TrF/LimbF) and trunk fat-to-total fat (TrF/TotF), Limb and trunk fat decreased in all groups (p < 0.01). For both ratios of fat distribution, the rhGH treated group experienced an enhanced loss of truncal compared to peripheral fat (p less than or equal to 0.01), with no significant change for those administered rhIGF-I or FL. There was no association between change in fat distribution and indices of cardiovascular disease risk as determined by serum lipid/lipoprotein levels and maximal aerobic capacity. These results suggest that administration of rhGH facilitates a decrease in central compared to peripheral fat in older women undertaking a weight loss program that combines exercise and moderate caloric restriction, although no beneficial effects are conferred to lipid/lipoprotein profiles, Further, the effect of rhGH is not enhanced by combining rhCH with rhIGF-I administration. In addition, rhIGF-I does not augment the loss of trunk fat when administered alone.

The evolution and star formation of dwarf galaxies in the Fornax Cluster

We present the results of a spectroscopic survey of 675 bright (16.5 < b(J) < 18) galaxies in a 6 degrees field centred on the Fornax cluster with the FLAIR-II spectrograph on the UK Schmidt Telescope. Three galaxy samples were observed: compact galaxies to search for new blue compact dwarfs, candidate M 32-like compact dwarf ellipticals, and a subset of the brightest known cluster members in order to study the cluster dynamics. We measured redshifts for 516 galaxies, of which 108 were members of the Fornax Cluster. Defining dwarf galaxies to be those with b(J) greater than or equal to 15 (M-B greater than or equal to - 16.5), there are a total of 62 dwarf cluster galaxies in our sample. Nine of these are new cluster members previously misidentified as background galaxies. The cluster dynamics show that the dwarf galaxies are still falling into the cluster whereas the giants are virialized. We classified the observed galaxies as late-type if we detected H alpha emission at an equivalent width greater than 1 Angstrom. The spectra were obtained through fixed apertures, so they reflect activity in the galaxy cores, but this does not significantly bias the classifications of the compact dwarfs in our sample. The new classifications reveal a higher rate of star formation among the dwarf galaxies than suggested by morphological classification: 35 per cent have significant H alpha emission indicative of star formations but only 19 per cent were morphologically classified as late-types. The star-forming dwarf galaxies span the full range of physical sizes and we find no evidence in our data for a distinct class of star-forming blue compact dwarf (BCD) galaxy. The distribution of scale sizes is consistent with evolutionary processes which transform late-type dwarfs to early-type dwarfs. The fraction of dwarfs with active star formation drops rapidly towards the cluster centre: this is the usual density-morphology relation confirmed here for dwarf galaxies. The star-forming dwarfs are concentrated in the outer regions of the cluster, the most extreme in an infalling subcluster. We estimate gas depletion time-scales for five dwarfs with detected Hi emission: these are long (of order 10(10) yr), indicating that an active gas removal process must be involved if they are transformed into gas-poor dwarfs as they fall further into the cluster. Finally, in agreement with our previous results, we find no compact dwarf elliptical (M 32-like) galaxies in the Fornax Cluster.

Sequence analysis and expression of a virus-like particle protein,VLP2, from the parasitic wasp Venturia canescens

Endoparasitoid wasps produce maternal protein secretions, which are transported into the body of insect hosts at oviposition to regulate host physiology for successful development of their offspring. Venturia canescens calyx fluid contains so-called virus-like particles (VLPs) that are essential for immune evasion of the developing parasitoid inside the host. VLPs consist of four major proteins. In this paper, we describe the isolation and molecular cloning of a gene (vlp2) that is a constituent of VLPs and discuss its possible role in VLP structure and function.

Isolation and characterization of a neprilysin-like protein from Venturia canescens virus-like particles

Maternal protein secretions from endoparasitoid wasps are evolutionary adaptations to regulate host physiology as part of an extended wasp phenotype. Virus-like particles (VLPs) produced in the calyx region of Venturia canescens wasps are involved in immune evasion of the developing parasitoid inside the host. In contrast to polydnaviruses (PDVs), VcVLPs are devoid of any nucleic acids. To understand the role of these particles in the regulation of host physiology and phylogenetic relationship between VLPs and PDVs, it is essential to identify particle proteins. In this paper, we describe the isolation and molecular cloning of a neprilysin-like gene (VcNEP) coding for a 94 kDa VcVLP protein and discuss its possible role in host regulation.

Developing qualitative career assessment processes

Assessment has been integral to career counseling since the early 1900s. During that time, the greatest amount of attention was focused on quantitative assessment. Thus, there is still very little to guide the development and conduct of qualitative assessment in career counseling. The authors present an overview of qualitative career assessment and its theoretical underpinnings and propose suggestions that could guide the development of qualitative career assessment instruments.

Mental rotation processes in mathematically gifted boys: An fMRI investigation

The functional brain organisation of mathematically gifted adolescents may be different from those of average mathematical ability. In this study we used fMRI to examine the neural circuitry that mediates the performance of mathematically gifted boys and average ability controls while engaged in mental rotation. Eight math gifted male adolescents and five average ability male adolescents were presented 18 control and 18 mental rotation trials in two separate blocks. Participants selected one of four test stimuli to match the target stimulus by pressing one of four fibreoptic buttons. The control task required a simple 'best match' for the target stimulus. EPI scans were acquired on a 3-T MR scanner and a fixed effects statistical analysis (SPM99) was used to identify areas of significant activation in the rotation tasks, for the two groups. The results indicate that during mental rotation both groups activate the parietal lobes bilaterally, though to different levels. Moreover, the math gifted are uniformly bilateral in their pattern of activation, and engage some anterior regions not found in those of average ability. These regions include bilateral prefrontal cortex and the right anterior cingulate, which may serve to heighten concentration, and to optimise the pre-planning of purposeful actions.

Controlling chaos in a Lorenz-like system using feedback

We demonstrate that the dynamics of an autonomous chaotic laser can be controlled to a periodic or steady state under self-synchronization. In general, past the chaos threshold the dependence of the laser output on feedback applied to the pump is submerged in the Lorenz-like chaotic pulsation. However there exist specific feedback delays that stabilize the chaos to periodic behavior or even steady state. The range of control depends critically on the feedback delay time and amplitude. Our experimental results are compared with the complex Lorenz equations which show good agreement.

Image calibration to like-values in mapping shallow water quality from multitemporal data

The applicability of image calibration to like-values in mapping water quality parameters from multitemporal images is explored, Six sets of water samples were collected at satellite overpasses over Moreton Bay, Brisbane, Australia. Analysis of these samples reveals that waters in this shallow bay are mostly TSS-dominated, even though they are occasionally dominated by chlorophyll as well. Three of the images were calibrated to a reference image based on invariant targets. Predictive models constructed from the reference image were applied to estimating total suspended sediment (TSS) and Secchi depth from another image at a discrepancy of around 35 percent. Application of the predictive model for TSS concentration to another image acquired at a time of different water types resulted in a discrepancy of 152 percent. Therefore, image calibration to like-values could be used to reliably map certain water quality parameters from multitemporal TM images so long as the water type under study remains unchanged. This method is limited in that the mapped results could be rather inaccurate if the water type under study has changed considerably. Thus, the approach needs to be refined in shallow water from multitemporal satellite imagery.

The stability of the equilibrium outcomes in the admission games induced by stable matching rules

A stable matching rule is used as the outcome function for the Admission game where colleges behave straightforwardly and the students` strategies are given by their preferences over the colleges. We show that the college-optimal stable matching rule implements the set of stable matchings via the Nash equilibrium (NE) concept. For any other stable matching rule the strategic behavior of the students may lead to outcomes that are not stable under the true preferences. We then introduce uncertainty about the matching selected and prove that the natural solution concept is that of NE in the strong sense. A general result shows that the random stable matching rule, as well as any stable matching rule, implements the set of stable matchings via NE in the strong sense. Precise answers are given to the strategic questions raised.

Identification of a juvenile hormone esterase-like gene in the honey bee, Apis mellifera L. - Expression analysis and functional assays

Tight control over circulating juvenile hormone (JH) levels is of prime importance in an insect`s life cycle. Consequently, enzymes involved in JH metabolism, especially juvenile hormone esterases (JHEs), play major roles during metamorphosis and reproduction. In the highly eusocial Hymenoptera, JH has been co-opted into additional functions, primarily in the development of the queen and worker castes and in age-related behavioral development of workers. Within a set of 21 carboxylesterases predicted in the honey bee genome we identified one gene (Amjhe-like) that contained the main functional motifs of insect JHEs. Its transcript levels during larval development showed a maximum at the switch from feeding to spinning behavior, coinciding with a JH titer minimum. In adult workers, the highest levels were observed in nurse bees, where a low JH titer is required to prevent the switch to foraging. Functional assays showed that Amjhe-like expression is induced by JH-III and suppressed by 20-hydroxyecdysone. RNAi-mediated silencing of Amjhe-like gene function resulted in a six-fold increase in the JH titer in adult worker bees. The temporal profile of Amjhe-like expression in larval and adult workers, the pattern of hormonal regulation and the knockdown phenotype are consistent with the function of this gene as an authentic JHE. (C) 2008 Elsevier Inc. All rights reserved.

Therapeutic administration of KM+ lectin protects mice against Paracoccidioides brasiliensis infection via interleukin-12 production in a Toll-like receptor 2-dependent mechanism

KM+ is a mannose-binding lectin from Artocarpus integrifolia that induces interleukin (IL)-12 production by macrophages and protective T helper I immune response against Leishmania major infection. in this study, we performed experiments to evaluate the therapeutic activity of jackfruit KM+ (jfKM(+)) and its recombinant counterpart (rKM(+)) in experimental paracoccidioidomycosis. To this end, jfKM(+) or rKM(+) was administered to BALB/c mice 10 days after infection with Paracoccidiodes brasiliensis. Thirty days postinfection, lungs from the KM+-treated mice contained significantly fewer colony-forming units and little to no organized granulomas compared to the controls. In addition, lung homogenates from the KM+-treated mice presented higher levels of nitric oxide, IL-12, interferon-gamma, and tumor necrosis factor-a, whereas higher levels of IL-4 and IL-10 were detected in the control group. With mice deficient in IL-12, Toll-like receptor (TLR) 2, TLR4, or TLR adaptor molecule MyD88, we demonstrated that KM+ led to protection against P. brasiliensis infection through IL-12 production, which was dependent on TLR2. These results demonstrated a beneficial effect of KM+ on the severity of P. brasiliensis infection and may expand its potential use as a novel immunotherapeutic molecule.