842 research outputs found
Possible background reductions in double beta decay experiments
The background induced by radioactive impurities of and
in the source of the double beta experiment NEMO-3 has been
investigated. New methods of data analysis which decrease the background from
the above mentioned contamination are identified. The techniques can also be
applied to other double beta decay experiments capable of measuring
independently the energies of the two electrons.Comment: 15 pages, 13 figures, accepted in the Nuclear Instruments and Methods
Saturation physics and angular correlations at RHIC and LHC
We investigate the angular correlation between pions and photons produced in
deuteron-gold collisions at RHIC and proton-lead collisions at LHC using the
Color Glass Condensate formalism and make predictions for the dependence of the
production cross section on the angle between the pion and photon at different
rapidities and transverse momenta. Measuring this dependence would shed further
light on the role of high gluon density and saturation dynamics at RHIC and
LHC.Comment: 2-column EPJ C format, requires svjour.cls and svepj.clo; 4 pages, 4
figure
Heavy-quark energy loss in pQCD and SYM plasmas
We consider heavy-quark energy loss and pT-broadening in a strongly-coupled
N=4 Super Yang Mills (SYM) plasma, and the problem of finite-extend matter is
addressed. When expressed in terms of the appropriate saturation momentum, one
finds identical parametric forms for the energy loss in pQCD and SYM theory,
while pT-broadening is radiation dominated in SYM theory and multiple
scattering dominated in pQCD.Comment: 5 pages, 2 figures, Proceedings of the IIIrd Workshop for Young
Scientists on the Physics of Ultrarelativistic Nucleus-Nucleus Collisions
(HotQuarks08), Estes Park, USA, August 18-23 200
Effects of Crime Type and Location on Park Use Behavior
Crime and the fear of crime can be a barrier to park use, and locations of crimes can have varied effects. Unsafe areas in or around the park, around the residence, or along the route to the park can alter park use behavior. Our study aimed to examine associations between objective measures of types and location of crimes and park use behaviors. In 2013 we surveyed a sample (N = 230) of residents in Greensboro, North Carolina, about park use, with responses matched to objective crime and spatial measures. We measured all crimes and violent crimes near home, near the closest park, and along the shortest route between home and park. By using ordered and binary logistic modeling, we examined the relationships between the locations of crime and park use and duration of park visit, park rating, and never visiting parks. Additional models included distance to the closest park. Increased crime in parks and near home was associated with fewer park visits. Greater violent crime in all locations was related to fewer park visits. Park ratings were lower for parks with high violent crime rates. Given the importance of parks as settings for outdoor recreation and physical activity, crime may have a detrimental effect on physical activity and, therefore, public health
Reduction of peritoneal trauma by using nonsurgical gauze leads to less implantation metastasis of spilled tumor cells
OBJECTIVES: To evaluate whether infliction of peritoneal trauma would
promote tumor cell adherence to damaged peritoneal surfaces; to
investigate whether peritoneal damage could promote tumor growth of
extraperitoneal tumors; and to evaluate whether the amount of trauma
correlated with the degree of tumor cell adherence and local and distant
tumor growth. BACKGROUND DATA: After potentially curative resection of
colorectal carcinoma, the most common site for recurrence is locoregional.
We previously demonstrated that surgical trauma induces a cascade of
events leading to adhesion formation. The same mechanisms may be
responsible for improved tumor cell adherence and growth facilitation in
early local recurrence. METHODS: A reproducible rat model was used in
which peritoneal damage was inflicted by standardized rubbing of the
peritoneum with surgical gauzes of different texture. In the first
experiment, tumor cell adherence and growth at traumatized and
nontraumatized peritoneal sites were assessed semiquantitatively 3 weeks
after perioperative intra-abdominal injection of CC-531 tumor cells. In
the second experiment, the effect of peritoneal trauma on ectopic tumor
growth was investigated (CC-531 implanted under the renal capsule). In the
final experiment, we evaluated how soon after peritoneal traumatization
tumor cell adhesion and growth-promoting factors were active and whether
they could be passively transferred to naive nontraumatized abdominal
cavities. RESULTS: A significant correlation between the amount of
peritoneal trauma and the degree of tumor take at damaged peritoneal
surfaces was found (p < or = 0.018). Tumor take at remote peritoneal sites
not directly traumatized was also significantly higher after severe trauma
than after moderate trauma of the peritoneum (p < or = 0.005). In
addition, a significant correlation between the degree of peritoneal
trauma and the growth of ectopic tumors under the renal capsule was
observed (p < or = 0.009). The final experiment demonstrated that within a
few hours after infliction of peritoneal trauma, tumor growth-promoting
effects could be passively transferred to naive recipients. CONCLUSIONS:
Surgical trauma is an important factor in the promotion of local
recurrence. The enhancing effect of trauma is not restricted to the
inflicted site but rather has a generalized character. Avoidance of
unnecessary surgical trauma by using gentle techniques and materials is
therefore indicated
The next-to-leading order forward jet vertex in the small-cone approximation
We consider within QCD collinear factorization the process p+p to jet + jet
+X, where two forward high- jets are produced with a large separation in
rapidity (Mueller-Navelet jets). In this case the (calculable) hard
part of the reaction receives large higher-order corrections , which can be accounted for in the BFKL approach. In particular,
we calculate in the next-to-leading order the impact factor (vertex) for the
production of a forward high- jet, in the approximation of small aperture
of the jet cone in the pseudorapidity-azimuthal angle plane. The final
expression for the vertex turns out to be simple and easy to implement in
numerical calculations.Comment: 32 pages, 4 figures; a few comments and one reference added; a few
inessential misprints removed; version to appear on JHE
Scavenging of reactive oxygen species leads to diminished peritoneal tumor recurrence
Previously, we demonstrated that RBCs inhibit the recurrence of
perioperatively spilled tumor cells. The aim of this study was to identify
on which RBC component(s) the inhibitory effect is based. By using a
cell-seeding model in rats, the effect of RBC-related antioxidant
scavengers [hemoglobin, catalase, and superoxide dismutase (SOD)] on
peritoneal tumor recurrence was investigated. i.p. injection of hemoglobin
caused 45% more tumor load (P < 0.0001). At least 40% inhibition of tumor
recurrence was achieved with the use of catalase or SOD (P < 0.05).
Combining SOD and catalase did not lead to additional inhibition of tumor
recurrence. Inhibition of the overwhelmin
Technical design and performance of the NEMO3 detector
The development of the NEMO3 detector, which is now running in the Frejus
Underground Laboratory (L.S.M. Laboratoire Souterrain de Modane), was begun
more than ten years ago. The NEMO3 detector uses a tracking-calorimeter
technique in order to investigate double beta decay processes for several
isotopes. The technical description of the detector is followed by the
presentation of its performance.Comment: Preprint submitted to Nucl. Instrum. Methods A Corresponding author:
Corinne Augier ([email protected]
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