The UN in the lab

We consider two alternatives to inaction for governments combating terrorism, which we term Defense and Prevention. Defense consists of investing in resources that reduce the impact of an attack, and generates a negative externality to other governments, making their countries a more attractive objective for terrorists. In contrast, Prevention, which consists of investing in resources that reduce the ability of the terrorist organization to mount an attack, creates a positive externality by reducing the overall threat of terrorism for all. This interaction is captured using a simple 3×3 “Nested Prisoner’s Dilemma” game, with a single Nash equilibrium where both countries choose Defense. Due to the structure of this interaction, countries can benefit from coordination of policy choices, and international institutions (such as the UN) can be utilized to facilitate coordination by implementing agreements to share the burden of Prevention. We introduce an institution that implements a burden-sharing policy for Prevention, and investigate experimentally whether subjects coordinate on a cooperative strategy more frequently under different levels of cost sharing. In all treatments, burden sharing leaves the Prisoner’s Dilemma structure and Nash equilibrium of the game unchanged. We compare three levels of burden sharing to a baseline in a between-subjects design, and find that burden sharing generates a non-linear effect on the choice of the efficient Prevention strategy and overall performance. Only an institution supporting a high level of mandatory burden sharing generates a significant improvement in the use of the Prevention strategy

Massive Star Formation in the Molecular Ring Orbiting the Black Hole at the Galactic Center

A ring of dense molecular gas extending 2-7 pc orbits the supermassive black hole Sgr A* at the center of our Galaxy. Using the Green Bank Telescope, we detected water maser lines and both narrow (0.35 km/s) and broad (30 - 50 km/s) methanol emission from the molecular ring. Two of the strongest methanol lines at 44 GHz are confirmed as masers by interferometric observations. These class I methanol masers are collisionally excited and are signatures of early phases of massive star formation in the disk of the Galaxy, suggesting that star formation in the molecular ring is in its early phase. Close inspection of the kinematics of the associated molecular clumps in the HCN (J=1-0) line reveals broad red-shifted wings indicative of disturbance by protostellar outflows from young (few times 10^4 yr), massive stars embedded in the clumps. The thermal methanol profile has a similar shape, with a narrow maser line superimposed on a broad, red-shifted wing. Additional evidence for the presence of young massive protostars is provided by shocked molecular hydrogen and a number of striking ionized and molecular linear filaments in the vicinity of methanol sources suggestive of 0.5-pc scale protostellar jets. Given that the circumnuclear molecular ring is kinematically unsettled and thus is likely be the result of a recent capture, the presence of both methanol emission and broad, red-shifted HCN emission suggests that star formation in the circumnuclear ring is in its infancy.Comment: 13 pages, 4 figures, ApJ Letters (in press

Alternativas de planejamento para a exploração florestal.

No manejo sustentado em florestas tropicais, há necessidade da garantia de um fluxo constante de recursos para a sua viabilidade. No entanto, isso nem sempre é possível, pelo fato de a exploração ser realizada sem planejamento. Este trabalho tem como finalidade apresentar um método que auxilie no planejamento e na distribuição de recursos disponíveis, através da formulação de cenários para otimização do número de equipes para cada atividade da exploração dependente do tempo limite para conclusão dos trabalhos. Com base no tempo que uma equipe leva para executar determinada atividade e no seu sequenciamento, foram utilizadas técnicas da pesquisa operacional, para determinação do caminho crítico da cadeia de exploração de madeira nativa. Esses métodos, ao mesmo tempo em que organizam o sequenciamento das atividades e determinam quais delas devem receber maior atenção no planejamento, otimizam o número de equipes, para que toda a cadeia seja executada dentro de um tempo limite, o que se faz necessário na região, para que o ciclo de corte se limite à época de seca. O método proposto mostra-se como uma alternativa para o planejamento florestal das atividades de baixo impacto ao garantir o número ótimo de equipes e a realização de todo empreendimento no tempo estipulado

CARMA Large Area Star Formation Survey: Observational Analysis of Filaments in the Serpens South Molecular Cloud

We present the N2H+(J=1-0) map of the Serpens South molecular cloud obtained as part of the CARMA Large Area Star Formation Survey (CLASSy). The observations cover 250 square arcminutes and fully sample structures from 3000 AU to 3 pc with a velocity resolution of 0.16 km/s, and they can be used to constrain the origin and evolution of molecular cloud filaments. The spatial distribution of the N2H+ emission is characterized by long filaments that resemble those observed in the dust continuum emission by Herschel. However, the gas filaments are typically narrower such that, in some cases, two or three quasi-parallel N2H+ filaments comprise a single observed dust continuum filament. The difference between the dust and gas filament widths casts doubt on Herschel ability to resolve the Serpens South filaments. Some molecular filaments show velocity gradients along their major axis, and two are characterized by a steep velocity gradient in the direction perpendicular to the filament axis. The observed velocity gradient along one of these filaments was previously postulated as evidence for mass infall toward the central cluster, but these kind of gradients can be interpreted as projection of large-scale turbulence.Comment: 12 pages, 4 figures, published in ApJL (July 2014

Revealing The Millimeter Environment of the New FU Orionis Candidate HBC722 with the Submillimeter Array

We present 230 GHz Submillimeter Array continuum and molecular line observations of the newly discovered FUor candidate HBC722. We report the detection of seven 1.3 mm continuum sources in the vicinity of HBC722, none of which correspond to HBC722 itself. We compile infrared and submillimeter continuum photometry of each source from previous studies and conclude that three are Class 0 embedded protostars, one is a Class I embedded protostar, one is a Class I/II transition object, and two are either starless cores or very young, very low luminosity protostars or first hydrostatic cores. We detect a northwest-southeast outflow, consistent with the previous detection of such an outflow in low-resolution, single-dish observations, and note that its axis may be precessing. We show that this outflow is centered on and driven by one of the nearby Class 0 sources rather than HBC722, and find no conclusive evidence that HBC722 itself is driving an outflow. The non-detection of HBC722 in the 1.3 mm continuum observations suggests an upper limit of 0.02 solar masses for the mass of the circumstellar disk. This limit is consistent with typical T Tauri disks and with a disk that provides sufficient mass to power the burst.Comment: 12 pages, 7 figures, accepted by Ap

Targeting lentiviral vectors for cancer immunotherapy.

Delivery of tumour-associated antigens (TAA) in a way that induces effective, specific immunity is a challenge in anti-cancer vaccine design. Circumventing tumour-induced tolerogenic mechanisms in vivo is also critical for effective immunotherapy. Effective immune responses are induced by professional antigen presenting cells, in particular dendritic cells (DC). This requires presentation of the antigen to both CD4(+) and CD8(+) T cells in the context of strong co-stimulatory signals. Lentiviral vectors have been tested as vehicles, for both ex vivo and in vivo delivery of TAA and/or activation signals to DC, and have been demonstrated to induce potent T cell mediated immune responses that can control tumour growth. This review will focus on the use of lentiviral vectors for in vivo gene delivery to DC, introducing strategies to target DC, either targeting cell entry or gene expression to improve safety of the lentiviral vaccine or targeting dendritic cell activation pathways to enhance performance of the lentiviral vaccine. In conclusion, this review highlights the potential of lentiviral vectors as a generally applicable 'off-the-shelf' anti-cancer immunotherapeutic

Recovery of the physiological status in professional basketball players using NESA neuromodulation treatment during different types of microcycles in season: A preliminary randomized clinical trial.

The purpose of the study was to describe and compare recovery status after official basketball competition in players who underwent NESA neuromodulation treatment (NNT) in weeks with one or two matches. The recovery parameters of 12 professional male basketball players (mean ± SD, age: 20.6 ± 2.7 yr; height: 197.8 ± 11.7 cm; and body mass: 89.0 ± 21.2 kg) that competed in the LEB Plata (Spanish third division) were monitored 2 days after match-play over 6 weeks, and included: 1) the Hooper Test, which combines four subjective variables (sleep, stress, fatigue and soreness); 2) common biochemical markers (e.g., testosterone, cortisol and ratio T:C); and 3) lowest heart rate [HR], average HR, HR variability, sleep duration, awake time during night and onset latency before asleep). Players that completed NNT presented differences compared to the control group in sleep data. For instance, the lowest HR (p < 0.001), average HR (p < 0.001) and total awake time (p = 0.04) were significantly reduced in the NNT group. On the contrary, the control group presented greater values than the NNT group in the subjective Hooper Test, although only stress presented significant differences (Control 2.5 ± 1.2 vs. NNT cost or 3.2 ± 0.9; p = 0.01). Additionally, there were no significant differences in recovery parameters between weeks with one or two matches. In conclusion, the results suggest that players that underwent NNT tended to improve their sleep quality. Nevertheless, player’s values in the biochemical markers and wellness status remained similar in both groups. The fact that no significant differences were found between weeks with one or two matches could help basketball professionals to determine that a congested schedule does not seem to negatively alter recovery status.post-print1317 K

CARMA Large Area Star Formation Survey: Project Overview with Analysis of Dense Gas Structure and Kinematics in Barnard 1

We present details of the CARMA Large Area Star Formation Survey (CLASSy), while focusing on observations of Barnard 1. CLASSy is a CARMA Key Project that spectrally imaged N2H+, HCO+, and HCN (J=1-0 transitions) across over 800 square arcminutes of the Perseus and Serpens Molecular Clouds. The observations have angular resolution near 7" and spectral resolution near 0.16 km/s. We imaged ~150 square arcminutes of Barnard 1, focusing on the main core, and the B1 Ridge and clumps to its southwest. N2H+ shows the strongest emission, with morphology similar to cool dust in the region, while HCO+ and HCN trace several molecular outflows from a collection of protostars in the main core. We identify a range of kinematic complexity, with N2H+ velocity dispersions ranging from ~0.05-0.50 km/s across the field. Simultaneous continuum mapping at 3 mm reveals six compact object detections, three of which are new detections. A new non-binary dendrogram algorithm is used to analyze dense gas structures in the N2H+ position-position-velocity (PPV) cube. The projected sizes of dendrogram-identified structures range from about 0.01-0.34 pc. Size-linewidth relations using those structures show that non-thermal line-of-sight velocity dispersion varies weakly with projected size, while rms variation in the centroid velocity rises steeply with projected size. Comparing these relations, we propose that all dense gas structures in Barnard 1 have comparable depths into the sky, around 0.1-0.2 pc; this suggests that over-dense, parsec-scale regions within molecular clouds are better described as flattened structures rather than spherical collections of gas. Science-ready PPV cubes for Barnard 1 molecular emission are available for download.Comment: Accepted to The Astrophysical Journal (ApJ), 51 pages, 27 figures (some with reduced resolution in this preprint); Project website is at http://carma.astro.umd.edu/class