MARKET-MAKING BEHAVIOR IN FUTURES MARKETS

This paper examines voluntary market-making behavior, namely scalping, in futures markets. Specifically, this paper studies what factors determine scalpers' entry and exit, and how scalping affects market liquidity and price volatility. The data used for the analysis are time-stamped electronic transaction data marked with traders' identities from the Dalian Futures Exchanges in China. The contributions of this paper are: (1) to give detailed analysis of scalping behavior and its impact on market liquidity; (2) to develop new econometric tools for analyzing time-series count data; (3) to propose a new measure of liquidity.Liquidity, Market-Making, Futures Markets, Scalpers, Autoregressive Conditional Intensity (ACI), Volatility, Marketing,

A photon calorimeter using lead tungstate crystals for the CEBAF Hall A Compton polarimeter

The performances of the calorimeter of the Jlab Hall A Compton Polarimeter have been measured using the Mainz tagged photon beam.Comment: 13 page

Impact du Petit Age Glaciaire sur les plaines alluviales méditerranéenne françaises : apport de la géoarchéologie à l'évolution du bassin du Roussillon

International audienceDans la zone méditerranéenne, le Petit Age Glaciaire est enregistrée par le système fluvial sous le nom bien connu de "Younger Infill". Selon des résultats récents obtenus dans le bassin du Roussillon, nous proposons une première esquisse pour le moment, a savoir les causes et les conséquences de cet épisode climatique, basé à la fois sur des données géoarchéologiques et d'archives

First electron beam polarization measurements with a Compton polarimeter at Jefferson Laboratory

A Compton polarimeter has been installed in Hall A at Jefferson Laboratory. This letter reports on the first electron beam polarization measurements performed during the HAPPEX experiment at an electron energy of 3.3 GeV and an average current of 40 $\mu$A. The heart of this device is a Fabry-Perot cavity which increased the luminosity for Compton scattering in the interaction region so much that a 1.4% statistical accuracy could be obtained within one hour, with a 3.3% total error

The natural capital of temporary rivers: characterising the value of dynamic aquatic-terrestrial habitats. Valuing Nature Natural Capital Synthesis Reports, VNP12

Temporary rivers naturally transition between flowing, pool and dry states, creating aquatic–terrestrial habitat mosaics that change in space and time. These dynamic habitats are common in the UK's cool, wet climate. Here, they take many forms, from headwater streams that may dominate networks in remote uplands, to winterbourne rivers crossing the chalk of south England. We examine published and unpublished sources to provide an evidence-informed characterisation of the natural assets in temporary rivers

Angular Correlations in Internal Pair Conversion of Aligned Heavy Nuclei

We calculate the spatial correlation of electrons and positrons emitted by internal pair conversion of Coulomb excited nuclei in heavy ion collisions. The alignment or polarization of the nucleus results in an anisotropic emission of the electron-positron pairs which is closely related to the anisotropic emission of $\gamma$-rays. However, the angular correlation in the case of internal pair conversion exhibits diverse patterns. This might be relevant when investigating atomic processes in heavy-ion collisions performed at the Coulomb barrier.Comment: 27 pages + 6 eps figures, uses revtex.sty and epsf.sty, tar-compressed and uuencoded with uufile

Response of microchannel plates to single particles and to electromagnetic showers

We report on the response of microchannel plates (MCPs) to single relativistic particles and to electromagnetic showers. Particle detection by means of secondary emission of electrons at the MCP surface has long been proposed and is used extensively in ion time-of-flight mass spectrometers. What has not been investigated in depth is their use to detect the ionizing component of showers. The time resolution of MCPs exceeds anything that has been previously used in calorimeters and, if exploited effectively, could aid in the event reconstruction at high luminosity colliders. Several prototypes of photodetectors with the amplification stage based on MCPs were exposed to cosmic rays and to 491 MeV electrons at the INFN-LNF Beam-Test Facility. The time resolution and the efficiency of the MCPs are measured as a function of the particle multiplicity, and the results used to model the response to high-energy showers.Comment: Paper submitted to NIM

Examining the Usefulness of Patient Documentation Forms as a Tool for Community Health Navigators: Findings from the ENCOMPASS Pilot Study

Introduction | Effective documentation of patient encounters may influence Community Health Navigators’ (CHNs) success in providing support to patients as well as provide a data source to examine CHN practices. The ENhancing COMmunity health through Patient navigation, Advocacy, and Social Support (ENCOMPASS) study, based in partnership between the University of Calgary and the Mosaic Primary Care Network (MPCN) is evaluating a CHN program to determine whether CHNs improve outcomes for patients with multiple chronic conditions. CHNs support their patients by helping them navigate the health system, connect to community resources, and access culturally appropriate support. The purpose of this study was to examine the quality and usefulness of CHN-patient documentation forms used in the ENCOMPASS pilot study (i.e., Initial Action Planning Form, Follow-up Action Planning Form, Patient Encounter Form, all implemented on the REDCap platform) and revise the documentation process using co-design with the end user. Methods | An iterative co-design quality improvement process was employed across three phases. First, content analyses were conducted on the Patient Encounter Form notes to examine how CHNs were using the forms and how they were documenting their activities. Second, a survey was distributed to CHNs to gather their perspectives about their experiences with the REDCap platform and the three forms. Third, a working group, consisting of four CHNs, met twice with research team members to discuss barriers to use and opportunities for improvement. Results | The REDCap platform and the three CHN-patient encounter forms did not adequately meet the needs of the CHNs. Content analysis revealed significant variation in how the Patient Encounter Form was utilized and various form sections were not completed as intended. In the survey, CHNs reported that the documentation experience was not satisfactory and the training that they had received to date was insufficient. The CHN working group suggested changes to the interface with the REDCap platform and form structure. Revisions were made based on these suggestions, and approved by the working group. Conclusions | The approved changes to REDCap and the three forms will be implemented and introduced to the CHN team. The research team will develop a patient encounter documentation guidelines document and will provide all members of the CHN team with the opportunity to receive re-training. These changes will be reviewed with the CHNs to continue the iterative quality improvement process. Prior to final implementation, consultation with the Clinical Research Unit administrators on the feasibility of the revisions made to the forms and interface with the REDCap platform will be held. The results of this study have the potential to provide a better overall experience for CHNs in the ENCOMPASS program and enhance their work with patients

The rotation and coma profiles of comet C/2004 Q2 (Machholz)

Aims. Rotation periods of cometary nuclei are scarce, though important when studying the nature and origin of these objects. Our aim is to derive a rotation period for the nucleus of comet C/2004 Q2 (Machholz). Methods. C/2004 Q2 (Machholz) was monitored using the Merope CCD camera on the Mercator telescope at La Palma, Spain, in January 2005, during its closest approach to Earth, implying a high spatial resolution (50km per pixel). One hundred seventy images were recorded in three different photometric broadband filters, two blue ones (Geneva U and B) and one red (Cousins I). Magnitudes for the comet's optocentre were derived with very small apertures to isolate the contribution of the nucleus to the bright coma, including correction for the seeing. Our CCD photometry also permitted us to study the coma profile of the inner coma in the different bands. Results. A rotation period for the nucleus of P = 9.1 +/- 0.2 h was derived. The period is on the short side compared to published periods of other comets, but still shorter periods are known. Nevertheless, comparing our results with images obtained in the narrowband CN filter, the possibility that our method sampled P/2 instead of P cannot be excluded. Coma profiles are also presented, and a terminal ejection velocity of the grains v_gr = 1609 +/- 48 m/s is found from the continuum profile in the I band.Comment: 11 pages, 9 figures, accepted by A&