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Dual isotopic composition of methane in Murchison meteorite
Dual isotopic composition (H and C) of methane extracted from a small sample of Murchison meteorite reveals a deuterium enrichment for this molecule, indicating the presence of interstellar hydrogen
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Laser ablation of Diamond and Genesis concentrator target material
UV laser ablations of CVD diamond using two wavelengths of radiation (266 nm and 213 nm) have been compared. The impetus for this work is the 2004 return of Genesis and extraction of solar-wind oxygen implanted in diamond
Infertility problems and mental health symptoms in a community-based sample: depressive symptoms among infertile men, but not women
Most researchers agree that men’s and women’s experiences of infertility are
fundamentally different, and impacts upon the nature of psychological distress
encountered. However, design flaws, including non-random samples
unrepresentative of the general population, compromise many existing studies. Data
derived from a random general community sample provides prevalence of current
infertility, and permits examination of longitudinal associations between mental
health symptoms and infertility among 1,978 participants aged 28-32 years. In the
previous 12-months, infertility was experienced by 2.1% and 5.4% partnered men
and women. Infertility independently predicted depressive symptomatology in men,
and anxiety symptoms among women. Gender differences were sustained, even
controlling for prior depression and anxiety. Health professionals are encouraged
to proactively enquire about affective symptoms experienced by both women and
men with infertility problems
Micropolitics and working as a performance analyst in professional sport
This chapter introduces the background to, and theoretical concepts of, micropolitics, along with some of the key findings from related literature. It provides a discussion that emphasises performance analysts’ understanding of the complex and ambiguous nature of professional working life, and some suggestions for improving your ability to navigate the micropolitical terrain. Frequently used throughout the literature, Blase’s definition of micropolitics states that micro-politics refers to the use of formal and informal power by individuals and groups to achieve their goals. Key to Kelchtermans’ micro-political inquiry are two frameworks: subjective educational theory, which is the personal system of knowledge and beliefs about professional sport that practitioners use to perform their jobs, and the personal interpretive framework, which is the set of beliefs and representations developed over time that operates as a lens through which practitioners perceive their job situation and their behaviours
RF Issues and Developments at the LHC Machine
The main RF system of the LHC, which uses 400MHz superconducting cavities, will be used to capture, accelerate and store the injected beam. A separate transverse damper system using electrostatic deflectors will be used to damp transverse oscillations. The associated low-level RF (LLRF) equipment is responsible for fast control of the accelerating voltage and phase in the cavities, the phase and radial position of the beam, and the synchronization of beam transfers between SPS and LHC. The LLRF system combines highfrequency analogue components with digital signal processing using FPGAs and DSPs. The extensive use of digital technology allows not only to achieve the required performance and stability but also to provide full remote control and diagnostics facilities needed in a machine where most of the RF system is inaccessible during operation
MSYR—should the information which has become available since selections were made for RMP development in 1987 have changed perceptions on the likely range and relative plausibilities of values for this parameter for baleen whales
It is argued that continued attempts to estimate MSYR from accumulating data, to refine the plausible range of values for this parameter and relative plausibilities within this range, cannot be other than a crucial component of the process of development (and, in due course, refinement) of the Revised Management Procedure (RMP) and of the interpretation of the results of the associated Implementation Simulation Trials (ISTs) for particular RMP applications. In 1987, when the range of MSYR values for RMP trials was first specified, four of the six independent sources of information available suggested definite "low" MSYR values (~1%). None of these four sources appears to have survived to the present. Estimates of MSYR for twenty populations have become available since 1987 - eleven based on population model fits and the balance on the relationship MSYR > r(0)/2. Two arguments advanced previously against the use of this last relationship are considered: the one is dismissed because it lacks support in empirical data, while the other appears negated by an analysis by Best (1993). In the fourteen cases where estimates of MSYR (in terms of uniform selectivity harvesting on the 1+ population) are determined with reasonable precision, most lie in the 2%-6% range, and only one of these has a lower 90 or 95% confidence/probability bound below 1%. Cases of low point estimates of MSYR show wide confidence intervals not incompatible with this 2-6% range. Thus, evidence forthcoming since 1987 (much of it subsequent to 1993 when the Scientific Committee last discussed this issue substantively) would seem to support a change in the Committee's perception at that time of the likely range of values for MSYR for baleen whale stocks, as well as informing judgments on the relative plausibilities of values within this range
LCG MCDB -- a Knowledgebase of Monte Carlo Simulated Events
In this paper we report on LCG Monte Carlo Data Base (MCDB) and software
which has been developed to operate MCDB. The main purpose of the LCG MCDB
project is to provide a storage and documentation system for sophisticated
event samples simulated for the LHC collaborations by experts. In many cases,
the modern Monte Carlo simulation of physical processes requires expert
knowledge in Monte Carlo generators or significant amount of CPU time to
produce the events. MCDB is a knowledgebase mainly dedicated to accumulate
simulated events of this type. The main motivation behind LCG MCDB is to make
the sophisticated MC event samples available for various physical groups. All
the data from MCDB is accessible in several convenient ways. LCG MCDB is being
developed within the CERN LCG Application Area Simulation project
After the Standard Model: New Resonances at the LHC
Experiments will soon start taking data at CERN's Large Hadron Collider (LHC)
with high expectations for discovery of new physics phenomena. Indeed, the
LHC's unprecedented center-of-mass energy will allow the experiments to probe
an energy regime where the standard model is known to break down. In this
article, the experiments' capability to observe new resonances in various
channels is reviewed.Comment: Preprint version of a Brief Review for Modern Physics Letters A.
Changes w.r.t. the fully corrected version are smal
X-Ray Light Curves of Gamma-ray Bursts Detected with the All-Sky Monitor on RXTE
We present X-ray light curves (1.5-12 keV) for fifteen gamma-ray bursts
(GRBs) detected by the All-Sky Monitor on the Rossi X-ray Timing Explorer. We
compare these soft X-ray light curves with count rate histories obtained by the
high-energy (>12 keV) experiments BATSE, Konus-Wind, the BeppoSAX Gamma-Ray
Burst Monitor, and the burst monitor on Ulysses. We discuss these light curves
within the context of a simple relativistic fireball and synchrotron shock
paradigm, and we address the possibility of having observed the transition
between a GRB and its afterglow. The light curves show diverse morphologies,
with striking differences between energy bands. In several bursts, intervals of
significant emission are evident in the ASM energy range with little or no
corresponding emission apparent in the high-energy light curves. For example,
the final peak of GRB 970815 as recorded by the ASM is only detected in the
softest BATSE energy bands. We also study the duration of bursts as a function
of energy. Simple, singly-peaked bursts seem consistent with the E^{-0.5} power
law expected from an origin in synchrotron radiation, but durations of bursts
that exhibit complex temporal structure are not consistent with this
prediction. Bursts such as GRB 970828 that show many short spikes of emission
at high energies last significantly longer at low energies than the synchrotron
cooling law would predict.Comment: 15 pages with 20 figures and 2 tables. In emulateapj format. Accepted
by ApJ
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