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Ethical Issues in Genetic Testing for Inherited Cancer Predisposition Syndromes: the Potentially Conflicting Interests of Patients and Their Relatives
Purpose of Review
This review uses clinical cases to highlight some of the ethical dilemmas currently faced by oncologists, geneticists and others who request genetic testing for inherited cancer disorders.
Recent Findings
Recent ethical guidance supports clinicians in testing patients when other family members decline similar testing, even when such testing will reveal those family membersā genetic status. And increasingly there is acknowledgement that when a patient declines to share genetic results with family members, clinicians may have an ethical duty to breach patient confidentiality in order to inform at-risk relatives to whom they may owe a duty of care, so that they can choose to access genetic testing and potentially life-saving screening and treatment.
Summary
Genetic testing for inherited cancer disorders raises multiple ethical issues, which cannot always be easily resolved by discussion with patients, or with their family members. Clinical ethics committees can provide valuable assistance in resolving the dilemmas presented in these cases
Analytical models and system topologies for remote multispectral data acquisition and classification
Simple analytical models are presented of the radiometric and statistical processes that are involved in multispectral data acquisition and classification. Also presented are basic system topologies which combine remote sensing with data classification. These models and topologies offer a preliminary but systematic step towards the use of computer simulations to analyze remote multispectral data acquisition and classification systems
Viewgraph preparation made easier
Rolls of color-reversal film permit exposure of over 200 viewgraphs on one film loading. Time is saved in film development as roll film lends itself readily to automatic processing
Development of the (d,n) proton-transfer reaction in inverse kinematics for structure studies
Transfer reactions have provided exciting opportunities to study the
structure of exotic nuclei and are often used to inform studies relating to
nucleosynthesis and applications. In order to benefit from these reactions and
their application to rare ion beams (RIBs) it is necessary to develop the tools
and techniques to perform and analyze the data from reactions performed in
inverse kinematics, that is with targets of light nuclei and heavier beams. We
are continuing to expand the transfer reaction toolbox in preparation for the
next generation of facilities, such as the Facility for Rare Ion Beams (FRIB),
which is scheduled for completion in 2022. An important step in this process is
to perform the (d,n) reaction in inverse kinematics, with analyses that include
Q-value spectra and differential cross sections. In this way, proton-transfer
reactions can be placed on the same level as the more commonly used
neutron-transfer reactions, such as (d,p), (9Be,8Be), and (13C,12C). Here we
present an overview of the techniques used in (d,p) and (d,n), and some recent
data from (d,n) reactions in inverse kinematics using stable beams of 12C and
16O.Comment: 9 pages, 4 figures, presented at the XXXV Mazurian Lakes Conference
on Physics, Piaski, Polan
Key Ne states identified affecting -ray emission from F in novae
Detection of nuclear-decay rays provides a sensitive thermometer of
nova nucleosynthesis. The most intense -ray flux is thought to be
annihilation radiation from the decay of F, which is destroyed
prior to decay by the F(,)O reaction. Estimates of
F production had been uncertain, however, because key near-threshold
levels in the compound nucleus, Ne, had yet to be identified. This
Letter reports the first measurement of the
F(He,)Ne reaction, in which the placement of two
long-sought 3/2 levels is suggested via triton--
coincidences. The precise determination of their resonance energies reduces the
upper limit of the rate by a factor of at nova temperatures and
reduces the average uncertainty on the nova detection probability by a factor
of 2.1.Comment: 6 pages, 4 figure
New -ray Transitions Observed in Ne with Implications for the O(,)Ne Reaction Rate
The O(,)Ne reaction is responsible for breakout
from the hot CNO cycle in Type I x-ray bursts. Understanding the properties of
resonances between and 5 MeV in Ne is crucial in the
calculation of this reaction rate. The spins and parities of these states are
well known, with the exception of the 4.14- and 4.20-MeV states, which have
adopted spin-parities of 9/2 and 7/2, respectively. Gamma-ray
transitions from these states were studied using triton--
coincidences from the F(He,)Ne reaction measured
with GODDESS (Gammasphere ORRUBA Dual Detectors for Experimental Structure
Studies) at Argonne National Laboratory. The observed transitions from the
4.14- and 4.20-MeV states provide strong evidence that the values are
actually 7/2 and 9/2, respectively. These assignments are consistent
with the values in the F mirror nucleus and in contrast to previously
accepted assignments
Using \u3csup\u3e19\u3c/sup\u3eF(\u3csup\u3e3\u3c/sup\u3eHe, t)\u3csup\u3e19\u3c/sup\u3eNe\u3csup\u3eā\u3c/sup\u3e(Ī³) to study astrophysically important levels near the \u3csup\u3e18\u3c/sup\u3eF+ p threshold
A direct test of nova explosion models comes from the observation of Ī³ rays created in the decay of radioactive isotopes produced in the nova. One such isotope, 18F, is believed to be the main source of observable Ī³ rays at and below 511 keV. The main destruction mechanism of 18F is thought to be the 18F(p,Ī±)15O reaction, and uncertainties in the reaction rate arise from uncertainties in the energies, spins, and parities of the nuclear levels in 19Ne above the 18F+p threshold. To measure the properties of these levels, the 19F(3He,t)19Ne-(Ī³) reaction was studied at Argonne National Laboratory and the Nuclear Science Laboratory at the University of Notre Dame
Direct Reaction Measurements Using GODDESS
GODDESS is a coupling of the charged-particle detection system ORRUBA to the gamma-ray detector array Gammasphere. This coupling has been developed in order to facilitate the high-resolution measurement of direct reactions in normal and inverse kinematics with stable and radioactive beams. GODDESS has been commissioned using a beam of 134Xe at 10 MeV/A, in a campaign of stable beam measurements. The measurement demonstrates the capabilities of GODDESS under radioactive beam conditions, and provides the first data on the single-neutron states in 135Xe, including previously unobserved states based on the orbitals above the N=82 shell closure
Structure Studies of from the Be(d,p) reaction in inverse kinematics on a solid deuteron target
The low-lying structure of Be has remained an enigma for decades.
Despite numerous experimental and theoretical studies, large inconsistencies
remain. Being both unbound, and one neutron away from Be, the heaviest
bound beryllium nucleus, Be is difficult to study through simple
reactions with weak radioactive ion beams or more complex reactions with
stable-ion beams. Here, we present the results of a study using the
Be(d,p)Be reaction in inverse kinematics using a 9.5~MeV per
nucleon Be beam from the ISAC-II facility. The solid deuteron target of
IRIS was used to achieve an increased areal thickness compared to conventional
deuterated polyethylene targets. The Q-value spectrum below -4.4~MeV was
analyzed using a Bayesian method with GEANT4 simulations. A three-point angular
distribution with the same Q-value gate was fit with a mixture of - and
-wave, - and -wave, or pure -wave transfer. The Q-value spectrum
was also compared with GEANT simulations obtained using the energies and widths
of states reported in four previous works. It was found that our results are
incompatible with works that revealed a wide resonance but shows better
agreement with ones that reported a narrower width.Comment: 10 pages, 5 figure
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