Experimental conversion of colony social organization in fire ants (Solenopsis invicta): worker genotype manipulation in absence of queen effects

Colony social organization in the fire ant Solenopsis invicta appears to be under strong genetic control. In the invasive USA range, polygyny (multiple queens per colony) is marked by the presence of the Gp-9(b) allele in most of a colony's workers, whereas monogyny (single queen per colony) is associated with the exclusive occurrence of the Gp-9(B) allele. Ross and Keller, Behav Ecol Sociobiol 51:287-295 (2002) experimentally manipulated social organization by cross-fostering queens into colonies of the alternate form, thereby changing adult worker Gp-9 genotype frequencies over time. Although these authors showed that social behavior switched predictably when the frequency of b-bearing adult workers crossed a threshold of 5-10%, the possibility that queen effects caused the conversions could not be excluded entirely. We addressed this problem by fostering polygyne brood into queenright monogyne colonies. All such treatment colonies switched social organization to become polygyne, coincident with their proportions of b-bearing workers exceeding 12%. Our results support the conclusion that polygyny in S. invicta is induced by a minimum frequency of colony workers carrying the b allele, and further confirm that its expression is independent of queen genotype or history, worker genotypes at genes not linked to Gp-9, and colony genetic diversity.

Secretory component delays the conversion of secretory IgA into antigen-binding competent F(ab')2: a possible implication for mucosal defense.

Secretory component (SC) represents the soluble ectodomain of the polymeric Ig receptor, a membrane protein that transports mucosal Abs across epithelial cells. In the protease-rich environment of the intestine, SC is thought to stabilize the associated IgA by unestablished molecular mechanisms. To address this question, we reconstituted SC-IgA complexes in vitro by incubating dimeric IgA (IgAd) with either recombinant human SC (rSC) or SC isolated from human colostral milk (SCm). Both complexes exhibited an identical degree of covalency when exposed to redox agents, peptidyl disulfide isomerase, and temperature changes. In cross-competition experiments, 50% inhibition of binding to IgAd was achieved at approximately 10 nM SC competitor. Western blot analysis of IgAd digested with intestinal washes indicated that the alpha-chain in IgAd was primarily split into a 40-kDa species, a phenomenon delayed in rSC- or SCm-IgAd complexes. In the same assay, either of the SCs was resistant to degradation only if complexed with IgAd. In contrast, the kappa light chain was not digested at all, suggesting that the F(ab')2 region was left intact. Accordingly, IgAd and SC-IgAd digestion products retained functionality as indicated by Ag reactivity in ELISA. Size exclusion chromatography under native conditions of digested IgAd and rSC-IgAd demonstrates that SC exerts its protective role in secretory IgA by delaying cleavage in the hinge/Fc region of the alpha-chain, not by holding together degraded fragments. The function of integral secretory IgA and F(ab')2 is discussed in terms of mucosal immune defenses.

Detection of bias in animal model pedigree indices of heifers

Selostus: Eläinmalliin perustuvien hiehojen odotusarvojen luotettavuus jalostusarvon ennusteena

Model-Free Reconstruction of Excitatory Neuronal Connectivity from Calcium Imaging Signals

A systematic assessment of global neural network connectivity through direct electrophysiological assays has remained technically infeasible, even in simpler systems like dissociated neuronal cultures. We introduce an improved algorithmic approach based on Transfer Entropy to reconstruct structural connectivity from network activity monitored through calcium imaging. We focus in this study on the inference of excitatory synaptic links. Based on information theory, our method requires no prior assumptions on the statistics of neuronal firing and neuronal connections. The performance of our algorithm is benchmarked on surrogate time series of calcium fluorescence generated by the simulated dynamics of a network with known ground-truth topology. We find that the functional network topology revealed by Transfer Entropy depends qualitatively on the time-dependent dynamic state of the network (bursting or non-bursting). Thus by conditioning with respect to the global mean activity, we improve the performance of our method. This allows us to focus the analysis to specific dynamical regimes of the network in which the inferred functional connectivity is shaped by monosynaptic excitatory connections, rather than by collective synchrony. Our method can discriminate between actual causal influences between neurons and spurious non-causal correlations due to light scattering artifacts, which inherently affect the quality of fluorescence imaging. Compared to other reconstruction strategies such as cross-correlation or Granger Causality methods, our method based on improved Transfer Entropy is remarkably more accurate. In particular, it provides a good estimation of the excitatory network clustering coefficient, allowing for discrimination between weakly and strongly clustered topologies. Finally, we demonstrate the applicability of our method to analyses of real recordings of in vitro disinhibited cortical cultures where we suggest that excitatory connections are characterized by an elevated level of clustering compared to a random graph (although not extreme) and can be markedly non-local.

Increased Wnt signaling triggers oncogenic conversion of human breast epithelial cells by a Notch-dependent mechanism.

Wnt and Notch signaling have long been established as strongly oncogenic in the mouse mammary gland. Aberrant expression of several Wnts and other components of this pathway in human breast carcinomas has been reported, but evidence for a causative role in the human disease has been missing. Here we report that increased Wnt signaling, as achieved by ectopic expression of Wnt-1, triggers the DNA damage response (DDR) and an ensuing cascade of events resulting in tumorigenic conversion of primary human mammary epithelial cells. Wnt-1-transformed cells have high telomerase activity and compromised p53 and Rb function, grow as spheres in suspension, and in mice form tumors that closely resemble medullary carcinomas of the breast. Notch signaling is up-regulated through a mechanism involving increased expression of the Notch ligands Dll1, Dll3, and Dll4 and is required for expression of the tumorigenic phenotype. Increased Notch signaling in primary human mammary epithelial cells is sufficient to reproduce some aspects of Wnt-induced transformation. The relevance of these findings for human breast cancer is supported by the fact that expression of Wnt-1 and Wnt-4 and of established Wnt target genes, such as Axin-2 and Lef-1, as well as the Notch ligands, such as Dll3 and Dll4, is up-regulated in human breast carcinomas.

Effective t-J model Hamiltonian parameters of monolayered cuprate superconductors from ab initio electronic structure calculations

The magnetic coupling constant of selected cuprate superconductor parent compounds has been determined by means of embedded cluster model and periodic calculations carried out at the same level of theory. The agreement between both approaches validates the cluster model. This model is subsequently employed in state-of-the-art configuration interaction calculations aimed to obtain accurate values of the magnetic coupling constant and hopping integral for a series of superconducting cuprates. Likewise, a systematic study of the performance of different ab initio explicitly correlated wave function methods and of several density functional approaches is presented. The accurate determination of the parameters of the t-J Hamiltonian has several consequences. First, it suggests that the appearance of high-Tc superconductivity in existing monolayered cuprates occurs with J/t in the 0.20¿0.35 regime. Second, J/t=0.20 is predicted to be the threshold for the existence of superconductivity and, third, a simple and accurate relationship between the critical temperatures at optimum doping and these parameters is found. However, this quantitative electronic structure versus Tc relationship is only found when both J and t are obtained at the most accurate level of theory.

Iowa Prisoner Re-Entry Initiative (PRI) Rural Service Delivery Model Iowa Department of Correctional Services, November 2009

The Iowa Department of Corrections (DOC) and the Department of Human Rights, Division of Criminal and Juvenile Justice Planning (CJJP) entered into a contract for services from September 12, 2007 to June 30, 2009 for the purposes of assisting in the evaluation component for the two-year Iowa Prisoner Re-Entry Initiative (PRI) Rural Service Delivery Model. This contract was extended to November 2009. The Rural PRI grant period ran from July 1, 2007 to June 30, 2009 and was extended to November 30, 2009. The purpose of the program was to improve community safety by providing pre-release services and successful transition planning and aftercare services to offenders released from state institutions to the Second Judicial District Department of Correctional Services. Participants included all offenders released to the Second Judicial District during the grant period.

Conversion of an administrative record system for compatibility with the ICIDH.

This paper presents an account of considerations relevant to conversion of data in an administrative record system into categories compatible with the ICIDH. Existing information recorded for the Swiss disablement insurance scheme fairly readily generates impairment and disability data relating to the time of first contact with the scheme, and the means for conversion are illustrated. The system does not generate data relevant to handicap.

Neutralizing antibodies in Multiple Sclerosis a model-based analysis of Interferon beta signaling pathway in macrophages

Multiple Sclerosis is the most common non-traumatic cause of neurologicaldisability in young people. There is no cure yet, and until recently, few long-termtherapies existed. Interferon beta (IFNβ) was the first treatment, and remains the mostcommonly prescribed. One of the most significant problems of IFNβ therapy is theproduction of drug specific antibodies. Up to 45% of patients develop neutralizingantibodies (NAbs) to IFNβ products. The neutralizing antibody binds to the biologicalagent preventing its interaction with its receptor, inhibiting the biological action of theprotein, which abrogates the clinical efficacy of IFNβ treatment. Interferon-betamediates its response by binding to its high affinity cell surface receptor and initiatingthe JAK/STAT signalling cascade. In this project we have analyzed the IFNβ signalingpathway in macrophages when neutralizing antibodies are present. The response tothis pathway after IFNβ stimulation shows a transient oscillatory rhythm of STAT1phosphorylation, which varies as NAbs concentration increases. To improve ourunderstanding of that behavior, we extended an existing mathematical model based onnonlinear ordinary differential equations of JAK/STAT pathway by including IFN-NAbassociation and IFN-activation receptor. Combining our theoretical model withexperimental data we could study the role of neutralizing antibodies on the molecularresponse and determine its lifetime after cytokine stimulation.

Testing a large-scale forestry scenario model by means of successive inventories on a forest property

Abstract

Toward a novel forensic intelligence model: systematic profiling of false identity documents

False identity documents represent a serious threat through their production and use in organized crime and by terrorist organizations. The present-day fight against this criminal problem and threats to national security does not appropriately address the organized nature of this criminal activity, treating each fraudulent document on its own during investigation and the judicial process, which causes linkage blindness and restrains the analysis capacity. Given the drawbacks of this case-by-case approach, this article proposes an original model in which false identity documents are used to inform a systematic forensic intelligence process. The process aims to detect links, patterns, and tendencies among false identity documents in order to support strategic and tactical decision making, thus sustaining a proactive intelligence-led approach to fighting identity document fraud and the associated organized criminality. This article formalizes both the model and the process, using practical applications to illustrate its powerful capabilities. This model has a general application and can be transposed to other fields of forensic science facing similar difficulties.

Sisäinen tulosraportointi tietojohtamisen näkökulmasta. Case: Elcoteq Network Oyj

Tutkielman tarkoituksena oli tutkia, mitkä tekijät vaikuttavat sisäisen laskennan tulostiedon oikeellisuuteen ja miten tietojohtamisen keinoin voidaan taata yhteensopivuus ulkoisen ja sisäisen laskentatiedon välillä. Tekijöiden tunnistamisen ja huomioonottamisen kautta voidaan kehittää organisaation tietämystä ja suorituskykyä. Tutkimus oli empiirinen ja kuvaileva tapaustutkimus. Kvalitatiivista aineistoa kerättiin pääasiassa kyselylomakkeen, havainto -ja dokumenttiaineiston avulla. Aineisto analysoitiin teemoittelun avulla. Laskentaorganisaatioissa havaittiin mekaanisen ja orgaanisen tietopääomaympäristön piirteitä, jotka asettavat tiedon välitykselle,vuorovaikutukselle ja tietämyksen kehittymiselle omat rajoitteensa. Laskentaorganisaatioiden toimintaa ohjasivat mekaaniselle ympäristölle tyypilliset vastuu - ja raportointisuhteet, aikataulut ja raportointikäytännöt. Raportointijärjestelmään tarvittaisiin lisäkoulutusta, tiedon vertailtavuuteen ja tiedon oikeellisuuden takaamiseen lisää työvälineitä. Tiedon välittämistä ja kommunikointia pitäisi tehostaa aktiivisemmalla sähköisellä viestinnällä, mutta myös monipuolisemmalla viestintäkanavien käytöllä. Laskentaorganisaatioiden toimintaympäristössä havaittiin orgaanisen tietopääomaympäristön piirteitä, mikä edellyttäisi dialogia tukevien teknologioiden ja toimintatapojen tehokkaampaa käyttöä. Haasteena on maantieteellisen etäisyyden aiheuttamat rajoitteet sekä toiminnan mekaaninen luonne. Uutta konseptia käyttöönotettaessa keskustelut ja vuorovaikutus tukivat mallin kehittämistä ja käytännön sisäistämistä osaksi organisaation tietämystä. Viestintäkanavien käytön tehostamisella voitaisiin edesauttaa tiedon välittymistä. Tietämyksen ja suorituskyvyn kehittäminen laskentaorganisaatioissa edellyttää kuitenkin vuorovaikutteisuuden ja dialogin tukemista.