To select or to weigh: a comparative study of linear combination schemes for superparent-one-dependence estimators

We conduct a large-scale comparative study on linearly combining superparent-one-dependence estimators (SPODEs), a popular family of seminaive Bayesian classifiers. Altogether, 16 model selection and weighing schemes, 58 benchmark data sets, and various statistical tests are employed. This paper's main contributions are threefold. First, it formally presents each scheme's definition, rationale, and time complexity and hence can serve as a comprehensive reference for researchers interested in ensemble learning. Second, it offers bias-variance analysis for each scheme's classification error performance. Third, it identifies effective schemes that meet various needs in practice. This leads to accurate and fast classification algorithms which have an immediate and significant impact on real-world applications. Another important feature of our study is using a variety of statistical tests to evaluate multiple learning methods across multiple data sets.

Ectodysplasin A (EDA)-EDA receptor signalling and its pharmacological modulation

L'ectodysplasine Al (EDA1 ou EDA), un ligand de la famille du TNF, et son récepteur EDAR favorisent le développement des poils, des dents et de plusieurs types de glandes. Chez l'humain, une déficience en EDA cause une dysplasie ectodermique liée à l'X, caractérisée par la genèse défectueuse des phanères. Les souris Tabby, déficientes en Eda, présentent des symptômes similaires. Nous démontrons que les souris Tabby sont en moyenne 7% plus légères que les contrôles au moment du sevrage. Ce phénotype ne dépend pas du génotype des petits, mais exclusivement de celui de la mère, suggérant que l'absence d'EDA perturbe la fonction mammaire. La glande mammaire se développe en plusieurs étapes, principalement à la puberté et pendant la grossesse. Nous avons généré des anticorps pour activer ou inhiber la signalisation d'EDAR. Les anticorps agonistes corrigent le développement de souris ou de chiens déficients en EDA, alors que les antagonistes provoquent une dysplasie ectodermique chez les souris saines. L'exposition répétée de souris Tabby aux anticorps agonistes après le sevrage accroît la taille et la fonction des glandes sébacées, démonstration pharmacologique qu'EDA contrôle l'homéostasie de la glande sébacée adulte. Ces outils seront utiles pour étudier la fonction d'EDA aux diverses étapes du développement de la glande mammaire. Fc-EDAl, un stimulateur d'EDAR, est en phase d'évaluation clinique. Nous avons montré que les structures dépendantes d'EDA qui se forment à différentes étapes du développement répondent à l'action du Fc-EDAl dans des fenêtres temporelles étroites ou larges. De plus, certaines structures peuvent être induites plusieurs jours après le début naturel de leur formation. Alors que la plupart des structures se forment suite à un seul jour d'activation d'EDAR, d'autre demandent un temps de stimulation plus long. La formation des dents est régulée par des signaux activateurs et inhibiteurs. Une forte stimulation d'EDAR spécifiquement appliquée aux deux premières molaires induit des signaux négatifs qui avortent la formation de la troisième molaire, alors qu'une forte stimulation donnée à la troisième molaire la rend hypertrophique tout en induisant parfois une quatrième molaire jamais observée chez les souris de type sauvage ou Tabby. EDA est donc un activateur important de la formation dentaire. Pris dans leur ensemble, ces résultats ont des implications pour la thérapie des dysplasies ectodermiques. - The TNF family ligand Ectodysplasin Al (EDA1 or EDA) and its receptor ED AR regulate embryonic development of hair, teeth and several types of glands. In humans, EDA mutations cause X-linked hypohidrotic ectodermal dysplasia (XLHED), a condition characterized by defective development of skin appendages. £da-deficient (Tabby) mice suffer from similar defects. We observed that Tabby pups at weaning were on average 7% smaller than WT controls, a phenotype that was curiously not linked to the genotype of pups, but to that of mothers, suggesting decreased mammary gland function in the absence of EDA. Mammary glands develop in several steps, most of which are post-natal. We generated monoclonal antibodies to block or activate EDAR signaling. Agonist antibodies rescued developmental defects when administered timely in £cfo-deficient mice and dogs, whereas blocking antibodies induced ectodermal dysplasia in WT mice. Agonist antibodies administered after weaning in £da-deficient mice for several months markedly increased both size and function of sebaceous glands, providing the first demonstration that pharmacological activation of the EDAR pathway in adults can correct important aspects of the dry skin phenotype. This also highlights a role for EDA1 in the homeostasis of adult sebaceous glands. These tools will be useful to study the function of EDA 1 at different stages of mammary gland development. Another EDAR agonist, Fc-EDAl, is currently evaluated in clinical trials. We found that EDA 1-dependent structures forming at different time points during development can respond to Fc-EDAl during time response windows that are narrow or wide. Also, some structures can be triggered up to several days after their normal time of induction. While most structures could be rescued by a single day of EDAR signaling, others required longer exposure times to form. Tooth formation is regulated by activating and inhibitory signals that impact one on the other. When strong EDAR signals were specifically given to the first two molars, overwhelming inhibitory signals completely inhibited formation of the third molar. In contrast, strong signals specifically given to the third molar induced hypertrophy of the later with occasional appearance of a fourth molar never observed in WT or £da-deficient mice. This clearly positions EDA as an important activating signal in tooth formation. Taken together, these results have implications for the therapy of ectodermal dysplasias.

Multi-sided Böhm-Bawerk assignment markets: the nucleolus and the core-center

En aquest treball mostrem que, a diferència del cas bilateral, per als mercats multilaterals d'assignació coneguts amb el nom de Böhm-Bawerk assignment games, el nucleolus i el core-center, i. e. el centre de masses del core, no coincideixen en general. Per demostrar-ho provem que donant un m-sided Böhm-Bawerk assignment game les dues solucions anteriors poden obtenir-se respectivament del nucleolus i el core-center d'un joc convex definit en el conjunt format pels m sectors. Encara més, provem que per calcular el nucleolus d'aquest últim joc només les coalicions formades per un jugador o m-1 jugadors són importants. Aquests resultats simplifiquen el càlcul del nucleolus d'un multi-sided ¿¿ohm-Bawerk assignment market amb un número molt elevat d'agents.

Symmetrically multilateral-bargained allocations in multi-sided assignment markets

[cat] Aquest treball tracta d’extendre la noció d’equilibri simètric de negociació bilateral introduït per Rochford (1983) a jocs d’assignació multilateral. Un pagament corresponent a un equilibri simètric de negociación multilateral (SMB) és una imputación del core que garanteix que qualsevol agent es troba en equilibri respecte a un procés de negociación entre tots els agents basat en allò que cadascun d’ells podria rebre -i fer servir com a amenaça- en un ’matching’ òptim diferent al que s’ha format. Es prova que, en el cas de jocs d’assignació multilaterals, el conjunt de SMB és sempre no buit i que, a diferència del cas bilateral, no sempre coincideix amb el kernel (Davis and Maschler, 1965). Finalment, responem una pregunta oberta per Rochford (1982) tot introduïnt un conjunt basat en la idea de kernel, que, conjuntament amb el core, ens permet caracteritzar el conjunt de SMB.

The maximun and the addition of assigment games

[cat] En el context dels mercats a dues bandes, considerem, en primer lloc, que els jugadors poden escollir on dur a terme les seves transaccions. Mostrem que el joc corresponent a aquesta situació, que es representa pel màxim d’un conjunt finit de jocs d’assignació, pot ser un joc no equilibrat. Aleshores proporcionem condicions per a l’equilibri del joc i, per aquest cas, analitzem algunes propietats del core del joc. En segon lloc, considerem que els jugadors poden fer transaccions en diversos mercats simultàniament i, llavors, sumar els guanys obtinguts. El joc corresponent, representat per la suma d’un conjunt finit de jocs d’assignació, és equilibrat. A més a més, sota certes condicions, la suma dels cores dels dos jocs d’assignació coincideix amb el core del joc suma.

Nitric oxide synthase (NOS) inhibition for one week improves renal sodium and water excretion in cirrhotic rats with ascites

Normalization of the increased vascular nitric oxide (NO) generation with low doses of NG-nitro-L-arginine methyl ester (L-NAME) corrects the hemodynamic abnormalities of cirrhotic rats with ascites. We have undertaken this study to investigate the effect of the normalization of vascular NO production, as estimated by aortic cyclic guanosine monophosphate (cGMP) concentration and endothelial nitric oxide synthase (eNOS) protein expression in the aorta and mesenteric artery, on sodium and water excretion. Rats with carbon tetrachloride-induced cirrhosis and ascites were investigated using balance studies. The cirrhotic rats were separated into two groups, one receiving 0.5 mg/kg per day of L-NAME (CIR-NAME) during 7 d, whereas the other group (CIR) was administrated the same volume of vehicle. Two other groups of rats were used as controls, one group treated with L-NAME and another group receiving the same volume of vehicle. Sodium and water excretion was measured on days 0 and 7. On day 8, blood samples were collected for electrolyte and hormone measurements, and aorta and mesenteric arteries were harvested for cGMP determination and nitric oxide synthase (NOS) immunoblotting. Aortic cGMP and eNOS protein expression in the aorta and mesenteric artery were increased in CIR as compared with CIR-NAME. Both cirrhotic groups had a similar decrease in sodium excretion on day 0 (0.7 versus 0.6 mmol per day, NS) and a positive sodium balance (+0.9 versus +1.2 mmol per day, NS). On day 7, CIR-NAME rats had an increase in sodium excretion as compared with the CIR rats (sodium excretion: 2.4 versus 0.7 mmol per day, P < 0.001) and a negative sodium balance (-0.5 versus +0.8 mmol per day, P < 0.001). The excretion of a water load was also increased after L-NAME administration (from 28+/-5% to 65+/-7, P < 0.05). Plasma renin activity, aldosterone and arginine vasopressin were also significantly decreased in the CIR-NAME, as compared with the CIR rats. The results thus indicate that normalization of aortic cGMP and eNOS protein expression in vascular tissue is associated with increased sodium and water excretion in cirrhotic rats with ascites.

In vivo assessment of use-dependent brain plasticity--beyond the "one trick pony" imaging strategy.

This article has been written as a comment to Dr Thomas and Dr Baker's article "Teaching an adult brain new tricks: A critical review of evidence for training-dependent structural plasticity in humans". We deliberately expand on the key question about the biological substrates underlying use-dependent brain plasticity rather than reiterating the authors' main points of criticism already addressed in more general way by previous publications in the field. The focus here is on the following main issues: i) controversial brain plasticity findings in voxel-based morphometry studies are partially due to the strong dependency of the widely used T1-weighted imaging protocol on varying magnetic resonance contrast contributions; ii) novel concepts in statistical analysis allow one to directly infer topological specificity of structural brain changes associated with plasticity. We conclude that iii) voxel-based quantification of relaxometry derived parameter maps could provide a new perspective on use-dependent plasticity by characterisation of brain tissue property changes beyond the estimation of volume and cortical thickness changes. In the relevant sections we respond to the concerns raised by Dr Thomas and Dr Baker from the perspective of the proposed data acquisition and analysis strategy.

Development and application of a one-step low cost procedure to concentrate viruses from seawater samples

A novel and simple procedure for concentrating adenoviruses from seawater samples is described. The technique entails the adsorption of viruses to pre-flocculated skimmed milk proteins, allowing the flocs to sediment by gravity, and dissolving the separated sediment in phosphate buffer. Concentrated virus may be detected by PCR techniques following nucleic acid extraction. The method requires no specialized equipment other than that usually available in routine public health laboratories, and due to its straightforwardness it allows the processing of a larger number of water samples simultaneously. The usefulness of the method was demonstrated in concentration of virus in multiple seawater samples during a survey of adenoviruses in coastal waters.

Consequences of one-week creatine supplementation on creatine and creatinine levels in athletes 'serum and urine

We explored the washout period of creatine (Cr) after repeated ingestions of high doses of exogenous Cr. Ten athletes ingested daily, in a randomized double-blind study design, 30 g of exoge- nous Cr (n = 5, Cr-group) or a placebo (n = 5, Pl-group). Serum and urine samples were collected 1) before supplementation (BEFO- RE), 2) after one week Cr supplementation (AFTER), and 3) one week later without supplementation (LATER). The Cr and crea- tinine (Crn) concentrations in serum (sCr, sCrn) and in multiple spots urine (uCr, uCrn) were measured. We observed a significant rise (p < 0.01) in sCr, uCr and sCrn between BEFORE and AFTER supplementation in Cr-group, as well as a significant difference between Cr-group and Pl-group. Body weight increased signifi- cantly (+1.5 kg), but relative body fat (%fat) was unchanged. After the washout period in LATER Cr-group, sCr and uCr decreased to low residual values. No loss of body weight occurred during thisperiod. In contrast, sCrn and uCrn returned to baseline values. In conclusion, regular uptake of high doses of exogenous Cr affects both Cr and Crn concentrations in serum (sCr: 14 folds; sCrn: 1.2 folds) and urine (uCr: 140 folds; uCrn: 1.5 folds). An abuse of Cr is therefore mostly spilled over in urine. Surprise drug tests, such as doping controls, happening during the period of Cr supplementa- tion can reveal an important increase in Cr and Crn concentrations, although subjects stopped suddenly Cr loading. The discernible effect of Cr supplementation on these values disappeared within one week.

Executive Order Number Eighty-One May 15, 2013

This order strengthens the Governor's Science, Technology, Engineering and Mathematics (STEM) Advisory Council.

Report of the Code Commission : to accompany the code as reported to the Twenty-sixth General Assembly of Iowa, in accordance with the provisions of chapter one hundred and fifteen of the acts of the Twenty-fifth General Assembly,1895.

This is the Report of the Code Commissioners to the Twenty-fifth General Assembly of the State of Iowa

One-year acyclovir prophylaxis for preventing varicella-zoster virus disease after hematopoietic cell transplantation: no evidence of rebound varicella-zoster virus disease after drug discontinuation.

No consensus exists on whether acyclovir prophylaxis should be given for varicella-zoster virus (VZV) prophylaxis after hematopoietic cell transplantation because of the concern of "rebound" VZV disease after discontinuation of prophylaxis. To determine whether rebound VZV disease is an important clinical problem and whether prolonging prophylaxis beyond 1 year is beneficial, we examined 3 sequential cohorts receiving acyclovir from day of transplantation until engraftment for prevention of herpes simplex virus reactivation (n = 932); acyclovir or valacyclovir 1 year (n = 1117); or acyclovir/valacyclovir for at least 1 year or longer if patients remained on immunosuppressive drugs (n = 586). In multivariable statistical models, prophylaxis given for 1 year significantly reduced VZV disease (P < .001) without evidence of rebound VZV disease. Continuation of prophylaxis beyond 1 year in allogeneic recipients who remained on immunosuppressive drugs led to a further reduction in VZV disease (P = .01) but VZV disease developed in 6.1% during the second year while receiving this strategy. In conclusion, acyclovir/valacyclovir prophylaxis given for 1 year led to a persistent benefit after drug discontinuation and no evidence of a rebound effect. To effectively prevent VZV disease in long-term hematopoietic cell transplantation survivors, additional approaches such as vaccination will probably be required.

The biomechanic origin of sprint performance enhancement after one-week creatine supplementation.

In order to test whether an improvement of maximal sprinting speed after creatine (Cr) supplementation was due to the increase of stride frequency (SF), stride length (SL) or both, 7 subjects ran 4 consecutive sprints after 1 week of placebo or Cr supplementation. SF and SL were assessed by a triaxial accelerometer. Compared to the placebo, Cr induced an increase of running speed (+1.4% p < 0.05) and SF (+1.5%, p < 0.01), but not of SL. The drop in performance following repeated sprints was partially prevented by Cr. In conclusion, exogenous Cr enhanced sprinting performance by increasing SF. This result may be related to the recent findings of shortening in muscular relaxation time after Cr supplementation.

Development of mental disorders one year after exposure to psychosocial stressors; a cohort study in primary care patients with a physical complaint.

BACKGROUND: Mental disorders, common in primary care, are often associated with physical complaints. While exposure to psychosocial stressors and development or presence of principal mental disorders (i.e. depression, anxiety and somatoform disorders defined as multisomatoforme disorders) is commonly correlated, temporal association remains unproven. The study explores the onset of such disorders after exposure to psychosocial stressors in a cohort of primary care patients with at least one physical symptom. METHOD: The cohort study SODA (SOmatization, Depression and Anxiety) was conducted by 21 private-practice GPs and three fellow physicians in a Swiss academic primary care centre. GPs included patients via randomized daily identifiers. Depression, anxiety or somatoform disorders were identified by the full Patient Health Questionnaire (PHQ), a validated procedure to identify mental disorders based on DSM-IV criteria. The PHQ was also used to investigate exposure to psychosocial stressors (before the index consultation and during follow up) and the onset of principal mental disorders after one year of follow up. RESULTS: From November 2004 to July 2005, 1020 patients were screened for inclusion. 627 were eligible and 482 completed the PHQ one year later and were included in the analysis (77%). At one year, prevalence of principal mental disorders was 30/153 (19.6% CI95% 13.6; 26.8) for those initially exposed to a major psychosocial stressor and 26/329 (7.9% CI95% 5.2; 11.4) for those not. Stronger association exists between psychosocial stressors and depression (RR = 2.4) or anxiety (RR = 3.5) than multisomatoforme disorders (RR = 1.8). Patients who are "bothered a lot" (subjective distress) by a stressor are therefore 2.5 times (CI95% 1.5; 4.0) more likely to experience a mental disorder at one year. A history of psychiatric comorbidities or psychological treatment was not a confounding factor for developing a principal mental disorder after exposure to psychosocial stressors. CONCLUSION: This primary care study shows that patients with physical complaints exposed to psychosocial stressors had a higher risk for developing mental disorders one year later. This temporal association opens the field for further research in preventive care for mental diseases in primary care patients.