Composition and distribution patterns of chewing lice of two neotropical species of Turdus

We analyzed the prevalence and intensity of chewing lice on two neotropical species of Turdus and identified morphological parameters of birds influencing louse population dynamics. The study was conducted in southernmost Rio Grande do Sul state (RS), Brazil, between July 2009 and June 2010. Chewing lice were collected by dust-ruffling. The prevalence of chewing lice on both species of Turdus was high. Chewing lice from both species of Turdus exhibit similar composition and distribution patterns. However, chewing lice were more abundant on Turdus rufiventris, whereas species richness was higher on Turdus amaurochalinus. Myrsidea and Brueelia were the most prevalent and abundant genera on both host species in all seasons of the year. A predominance of chewing louse females and adults was observed. Aggregated distributions were observed. Body length was the only morphological parameter correlated with louse abundance, suggesting that specimens with a larger body have a higher abundance of lice.     

On-line, voluntary control of human temporal lobe neurons

Daily life continually confronts us with an exuberance of external, sensory stimuli competing with a rich stream of internal deliberations, plans and ruminations. The brain must select one or more of these for further processing. How this competition is resolved across multiple sensory and cognitive regions is not known; nor is it clear how internal thoughts and attention regulate this competition. Recording from single neurons in patients implanted with intracranial electrodes for clinical reasons, here we demonstrate that humans can regulate the activity of their neurons in the medial temporal lobe (MTL) to alter the outcome of the contest between external images and their internal representation. Subjects looked at a hybrid superposition of two images representing familiar individuals, landmarks, objects or animals and had to enhance one image at the expense of the other, competing one. Simultaneously, the spiking activity of their MTL neurons in different subregions and hemispheres was decoded in real time to control the content of the hybrid. Subjects reliably regulated, often on the first trial, the firing rate of their neurons, increasing the rate of some while simultaneously decreasing the rate of others. They did so by focusing onto one image, which gradually became clearer on the computer screen in front of their eyes, and thereby overriding sensory input. On the basis of the firing of these MTL neurons, the dynamics of the competition between visual images in the subject's mind was visualized on an external display.     

Systemic Understanding of Coopetitive Behaviour in a Latin American Technological Park

The purpose of this article is to construct a systemic structure to explain the relations subjacent to the coopetitive behaviour observed in a Latin American technological park. The research method is qualitative modelling. The primary research technique is the in-depth interview with park experts. Systemic language organised the speeches. The systemic language uses symbols that represent the elements of a system, such as variables, relations, and feedback loops. Initially, we constructed two essential archetypes that describe how the need for coopetition emerged, triggered by failures in meeting customers´ demands and reduced sales. Then, we built an overall systemic structure relying on the essential archetypes, which explains how the coopetitive strategy emerged in the park. The main conclusion reached by the study is learning and public policies as desirable conditions; failure in meeting customers’ requirements as the trigger; and sustainability, knowledge and resource sharing, mitigation of risks and uncertainties, and increased sales by price reduction, as reinforcing feedback factors. The main contribution of the study is a systemic qualitative model that helps understanding how to implement or manage a coopetitive strategy in a network formed of companies mainly driven by technological factors.     

Exome sequencing identifies MAX mutations as a cause of hereditary pheochromocytoma

Hereditary pheochromocytoma (PCC) is often caused by germline mutations in one of nine susceptibility genes described to date, but there are familial cases without mutations in these known genes. We sequenced the exomes of three unrelated individuals with hereditary PCC (cases) and identified mutations in MAX, the MYC associated factor X gene. Absence of MAX protein in the tumors and loss of heterozygosity caused by uniparental disomy supported the involvement of MAX alterations in the disease. A follow-up study of a selected series of 59 cases with PCC identified five additional MAX mutations and suggested an association with malignant outcome and preferential paternal transmission of MAX mutations. The involvement of the MYC-MAX-MXD1 network in the development and progression of neural crest cell tumors is further supported by the lack of functional MAX in rat PCC (PC12) cells and by the amplification of MYCN in neuroblastoma and suggests that loss of MAX function is correlated with metastatic potential.     

Emerging topics and new perspectives on HLA-G

Following the Fifth International Conference on non-classical HLA-G antigens (HLA-G), held in Paris in July 2009, we selected some topics which focus on emerging aspects in the setting of HLA-G functions. In particular, HLA-G molecules could play a role in: (1) various inflammatory disorders, such as multiple sclerosis, intracerebral hemorrhage, gastrointestinal, skin and rheumatic diseases, and asthma, where they may act as immunoregulatory factors; (2) the mechanisms to escape immune surveillance utilized by several viruses, such as human cytomegalovirus, herpes simplex virus type 1, rabies virus, hepatitis C virus, influenza virus type A and human immunodeficiency virus 1 (HIV-1); and (3) cytokine/chemokine network and stem cell transplantation, since they seem to modulate cell migration by the downregulation of chemokine receptor expression and mesenchymal stem cell activity blocking of effector cell functions and the generation of regulatory T cells. However, the immunomodulatory circuits mediated by HLA-G proteins still remain to be clarified.     

ASIP and TYR pigmentation variants associate with cutaneous melanoma and basal cell carcinoma

Fair color increases risk of cutaneous melanoma (CM) and basal cell carcinoma (BCC). Recent genome-wide association studies have identified variants affecting hair, eye and skin pigmentation in Europeans. Here, we assess the effect of these variants on risk of CM and BCC in European populations comprising 2,121 individuals with CM, 2,163 individuals with BCC and over 40,000 controls. A haplotype near ASIP, known to affect a similar spectrum of pigmentation traits as MC1R variants, conferred significant risk of CM (odds ratio (OR) = 1.45, P = 1.2 x 10(-9)) and BCC (OR = 1.33, P = 1.2 x 10(-6)). The variant in TYR encoding the R402Q amino acid substitution, previously shown to affect eye color and tanning response, conferred risk of CM (OR = 1.21, P = 2.8 x 10(-7)) and BCC (OR = 1.14, P = 6.1 x 10(-4)). An eye color variant in TYRP1 was associated with risk of CM (OR = 1.15, P = 4.6 x 10(-4)). The association of all three variants is robust with respect to adjustment for the effect of pigmentation.     

Predictability of Equity Models

In this study, we verify the existence of predictability in the Brazilian equity market. Unlike other studies in the same sense, which evaluate original series for each stock, we evaluate synthetic series created on the basis of linear models of stocks. Following the approach of Burgess (Computational Finance, 1999; 99, 297–312), we use the ‘stepwise regression’ model for the formation of models of each stock. We then use the variance ratio profile together with a Monte Carlo simulation for the selection of models with potential predictability using data from 1 April 1999 to 30 December 2003. Unlike the approach of Burgess, we carry out White's Reality Check (Econometrica, 2000; 68, 1097–1126) in order to verify the existence of positive returns for the period outside the sample from 2 January 2004 to 28 August 2007. We use the strategies proposed by Sullivan, Timmermann and White (Journal of Finance, 1999; 54, 1647–1691) and Hsu and Kuan (Journal of Financial Econometrics, 2005; 3, 606–628) amounting to 26,410 simulated strategies. Finally, using the bootstrap methodology, with 1000 simulations, we find strong evidence of predictability in the models, including transaction costs. Copyright © 2015 John Wiley & Sons, Ltd.     

Caveolar targeting links Kv1.3 with the insulin-dependent adipocyte physiology

The voltage-dependent potassium channel Kv1.3 participates in peripheral insulin sensitivity. Genetic ablation of Kv1.3 triggers resistance to diet-induced weight gain, thereby pointing to this protein as a pharmacological target for obesity and associated type II diabetes. However, this role is under intense debate because Kv1.3 expression in adipose tissue raises controversy. We demonstrated that Kv1.3 is expressed in white adipose tissue from humans and rodents. Moreover, other channels, such as Kv1.1, Kv1.2, Kv1.4 and especially Kv1.5, from the same Shaker family are also present. Although elevated insulin levels and adipogenesis remodel the Kv phenotype, which could lead to multiple heteromeric complexes, Kv1.3 markedly participates in the insulin-dependent regulation of glucose uptake in mature adipocytes. Adipocyte differentiation increased the expression of Kv1.3, which is targeted to caveolae by molecular interactions with caveolin 1. Using a caveolin 1-deficient 3T3-L1 adipocyte cell line, we demonstrated that the localization of Kv1.3 in caveolar raft structures is important for proper insulin signaling. Insulin-dependent phosphorylation of the channel occurs at the onset of insulin-mediated signaling. However, when Kv1.3 was spatially outside of these lipid microdomains, impaired phosphorylation was exhibited. Our data shed light on the putative role of Kv1.3 in weight gain and insulin-dependent responses contributing to knowledge about adipocyte physiology.