Comment on "Canonical formalism for Lagrangians with nonlocality of finite extent"

We show by some counterexamples that Lagrangian sysytems with nonlocality of finite extent are not necessarily unstable.Comment: 8 pages, 1 figure Submitted to Phys. Rev.

Hamiltonian Formalism for Space-time Non-commutative Theories

Space-time non-commutative theories are non-local in time. We develop the Hamiltonian formalism for non-local field theories in d space-time dimensions by considering auxiliary d+1 dimensional field theories which are local with respect to the evolution time. The Hamiltonian path integral quantization is considered and the Feynman rules in the Lagrangian formalism are derived. The case of non-commutative \phi^3 theory is considered as an example.Comment: 6 pages, A new section is added with other comments and references. To appear in PR

Site-Specific Integration of Foreign DNA into Minimal Bacterial and Human Target Sequences Mediated by a Conjugative Relaxase

This is an open-access article distributed under the terms of the Creative Commons Attribution License.[Background]: Bacterial conjugation is a mechanism for horizontal DNA transfer between bacteria which requires cell to cell contact, usually mediated by self-transmissible plasmids. A protein known as relaxase is responsible for the processing of DNA during bacterial conjugation. TrwC, the relaxase of conjugative plasmid R388, is also able to catalyze site-specific integration of the transferred DNA into a copy of its target, the origin of transfer (oriT), present in a recipient plasmid. This reaction confers TrwC a high biotechnological potential as a tool for genomic engineering. [Methodology/Principal Findings]: We have characterized this reaction by conjugal mobilization of a suicide plasmid to a recipient cell with an oriT-containing plasmid, selecting for the cointegrates. Proteins TrwA and IHF enhanced integration frequency. TrwC could also catalyze integration when it is expressed from the recipient cell. Both Y18 and Y26 catalytic tyrosil residues were essential to perform the reaction, while TrwC DNA helicase activity was dispensable. The target DNA could be reduced to 17 bp encompassing TrwC nicking and binding sites. Two human genomic sequences resembling the 17 bp segment were accepted as targets for TrwC-mediated site-specific integration. TrwC could also integrate the incoming DNA molecule into an oriT copy present in the recipient chromosome. [Conclusions/Significance]: The results support a model for TrwC-mediated site-specific integration. This reaction may allow R388 to integrate into the genome of non-permissive hosts upon conjugative transfer. Also, the ability to act on target sequences present in the human genome underscores the biotechnological potential of conjugative relaxase TrwC as a site-specific integrase for genomic modification of human cells.This work was supported by grant BIO2008-00133 from the Spanish Ministry of Science and Innovation to ML. CGP was a recipient of a predoctoral fellowship from the University of Cantabria, Spain.Peer reviewe

Short and Longer-term Psychological Consequences of Operation Cast Lead: documentation from a Mental Health program in the Gaza Strip

<p>Abstract</p> <p>Background</p> <p>There is growing recognition of the psychological impact of adversity associated with armed conflict on exposed civilian populations. Yet there is a paucity of evidence on the value of mental health programs in these contexts, and of the chronology of psychological sequelae, especially in prolonged conflicts with repeated cycles of extreme violence. Here, we describe changes in the psychological profile of new patients in a mental health program after the military offensive Cast Lead, in the context of the prolonged armed conflict involving the Gaza Strip.</p> <p>Methods</p> <p>This study analyses routinely collected program data from a Médecins Sans Frontières mental health program in the Gaza Strip spanning 2007–2011. Data consist of socio-demographic as well as clinical baseline and follow-up data on new patients entering the program. Comparisons were made through Chi square and Fisher’s exact tests, univariate and multivariate logistic and linear regression.</p> <p>Results</p> <p>PTSD, depression and other anxiety disorders were the most frequent psychopathologies, with 21% having multiple diagnoses. With a median of nine sessions, clinical improvement was recorded for 83% (1122/1357), and more common for those with separation anxiety, acute and posttraumatic disorders as principal diagnosis (855/1005), compared to depression (141/183, p<0.01). Noted changes proximal to Operation Cast Lead were: a doubling in patient case load with a broader socio-economic background, shorter interval from an identified traumatic event to seeking care, and a rise in diagnoses of acute and posttraumatic stress disorders. Sustained changes included: high case load, more distal triggering events, and increase in diagnoses of other anxiety disorders (especially for children 15 years and younger) and depression (especially for patients 16 years and older).</p> <p>Conclusion</p> <p>Evolving changes in patient volume, diagnoses and recall period to triggering events suggest a lengthy and durable effect of an intensified exposure to violence in a context of prolonged conflict. Our findings suggest that mental health related humanitarian relief in protracted conflicts might need to prepare for an increase in patients with changing profiles over an extended period following an acute flare-up in violence.</p

Osteosíntesis mínimamente invasiva con placa en fracturas de radio distal tipo C

Introducción. La tendencia hacia el uso de técnicas mínimamente invasivas (MIPO) en el tratamiento de fracturas se justifica, por la reducción de la exposición de la fractura y la disección de los planos musculares, lo que facilita la recuperación precoz. Material y Método. Se realizó un estudio en dos fases, la primera descriptiva retrospectiva de una serie de 48 casos, y la segunda, del estudio longitudinal prospectivo de una serie de 23 casos, que se sometieron a MIPO tras una fractura intraarticular de radio distal tipo C de AO. Además de las variables: edad, sexo, lateralidad y mecanismo de lesión, se evaluaron los resultados funcionales, dolor, rango de movimiento y fuerza, a través de Mayo Wrist Score escala y el cuestionario DASH. Las fracturas se clasificaron utilizando las directrices AO, se evaluaron los resultados radiológicos y complicaciones. Resultados. Se realizó la descripción del abordaje quirúrgico de los71 pacientes: 43 mujeres y 28 hombres, con una media de edad de 57 años. El lado más afectado fue el izquierdo con 51 casos. El resultado funcional fue 68,33 en el primer estudio (retrospectivo) y 85,86 en el estudio prospectivo. Observamos una pérdida de fuerza en comparación con el lado contralateral, medida con un dinamómetro, de 5,19 Kg. (retrospectivo) y 2,98 Kg. (prospectivo). Radiográ- ficamente no hubo colapso intraarticular o pérdida de la reducción en el estudio prospectivo, y la consolidación se obtuvo en el 100% de los casos. Se observó, en el segundo estudio, un caso de síndrome de dolor regional complejo y sólo un caso requirió la retirada de material debido a la protrusión dorsal de un tornillo. Conclusiones. Se trata de una técnica segura que permite la reducción y estabilización de las fracturas de la extremidad distal del radio. No solo la estética, sino también, los resultados funcionales son mejores con la técnica MIPO.Introduction. The current trend towards the use of minimally invasive techniques (MIPO) in the treatment of fractures is justified by the reduced exposure of the fracture and dissection of the muscle planes, which facilitates early recovery. Materials and Methods. We performed a double study, a retrospective descriptive study of a series of 48 cases and a prospective longitudinal study of a series of 23 patients that underwent MIPO after intra-articular distal radius fracture. In addition to the variables: age, sex, side and injury mechanism, etc., functional outcomes, pain, range of motion and strength, through Mayo Wrist Score scale and DASH were assessed. Fractures were classified using the AO guidelines, radiological results and complications were assessed. Results. We conducted the description of surgical approach with surgical images. We analyzed a total of 71 patients, 43 women and 28 men with a mean age of 57 years. The most affected side was the left with 51 cases. According to the Mayo Wrist Score, functional outcome was 68,33 in the first study (retrospective) and 85.86 in the prospective study. A mean loss in strength, measured with a dynamometer of 5,19 Kg. (retrospective) and 2,98 Kg. (prospective), was observed when compared to the contralateral side. Radiographically no intraarticular collapse or loss reduction were observed in prospective study, and consolidation was obtained in 100% of the cases. One case of complex regional pain syndrome was observed and only one case required the removal of material because of dorsal protrusion of a screw in this study. Conclusions. It is a safe technique that allows the reduction and stabilization of fractures of the distal radius. Not only the aesthetic but also functional results are better with MIPO technique

The Ostrogradskian Instability of Lagrangians with Nonlocality of Finite Extent

I reply to the objections recently raised by J. Llosa to my constructive proof that Lagrangians with nonlocality of finite extent inherit the full Ostrogradskian instability.Comment: 9 pages, LaTeX 2 epsilon, no figure

On the degrees of freedom of a semi-Riemannian metric

A semi-Riemannian metric in a n-manifold has n(n-1)/2 degrees of freedom, i.e. as many as the number of components of a differential 2-form. We prove that any semi-Riemannian metric can be obtained as a deformation of a constant curvature metric, this deformation being parametrized by a 2-for

A translocation motif in relaxase TrwC specifically affects recruitment by its conjugative type IV secretion system

Type IV secretion system (T4SS) substrates are recruited through a translocation signal that is poorly defined for conjugative relaxases. The relaxase TrwC of plasmid R388 is translocated by its cognate conjugative T4SS, and it can also be translocated by the VirB/D4 T4SS of Bartonella henselae, causing DNA transfer to human cells. In this work, we constructed a series of TrwC variants and assayed them for DNA transfer to bacteria and human cells to compare recruitment requirements by both T4SSs. Comparison with other reported relaxase translocation signals allowed us to determine two putative translocation sequence (TS) motifs, TS1 and TS2. Mutations affecting TS1 drastically affected conjugation frequencies, while mutations affecting either motif had only a mild effect on DNA transfer rates through the VirB/D4 T4SS of B. henselae. These results indicate that a single substrate can be recruited by two different T4SSs through different signals. The C terminus affected DNA transfer rates through both T4SSs tested, but no specific sequence requirement was detected. The addition of a Bartonella intracellular delivery (BID) domain, the translocation signal for the Bartonella VirB/D4 T4SS, increased DNA transfer up to 4% of infected human cells, providing an excellent tool for DNA delivery to specific cell types. We show that the R388 coupling protein TrwB is also required for this high-efficiency TrwC-BID translocation. Other elements apart from the coupling protein may also be involved in substrate recognition by T4SSs

Development of Silicon PhotoMultipliers at FBK-irst

We report on the development of Silicon PhotoMultipliers (SiPM) at the Fondazione Bruno Kessler (FBK)-irst (Trento, Italy) in the framework of a collaboration with INFN. Device geometry and technology are resumed, and selected results from the characterization of SiPM prototypes from three production batches are reported, including static, dynamic, and noise properties, as well as photodetection efficiency