Testing Superstring Theories with Gravitational Waves

We provide a simple transfer function that determines the effect of an early matter dominated era on the gravitational wave background and show that a large class of compactifications of superstring theory might be tested by observations of the gravitational wave background from inflation. For large enough reheating temperatures > 10^9 \GeV the test applies to all models containing at least one scalar with mass < 10^{12}\GeV that acquires a large initial oscillation amplitude after inflation and has only gravitational interaction strength, i.e., a field with the typical properties of a modulus.Comment: 5 pages 2 figures, v2: changes in presentation, refs revised, matches version in print in PR

Enhanced Inflation in the Dirac-Born-Infeld framework

We consider the Einstein equations within the DBI scenario for a spatially flat Friedmann-Robertson-Walker (FRW) spacetime without a cosmological constant. We derive the inflationary scenario by applying the symmetry transformations which preserve the form of the Friedmann and conservation equations. These form invariance transformations generate a symmetry group parametrized by the Lorentz factor \ga. We explicitly obtain an inflationary scenario by the cooperative effect of adding energy density into the Friedmann equation. For the case of a constant Lorentz factor, and under the slow roll assumption, we find the transformation rules for the scalar and tensor power spectra of perturbations as well as their ratio under the action of the form invariance symmetry group. Within this case and due to its relevance for the inflationary paradigm, we find the general solution of the dynamical equations for a DBI field driven by an exponential potential and show a broad set of inflationary solutions. The general solution can be split into three subsets and all these behave asymptotically as a power law solution at early and at late times.Comment: 9 pages, revtex 4.

Beyond Dopamine: GABA, Glutamate, and the Axial Symptoms of Parkinson Disease

Introduction: The axial symptoms of Parkinson disease (PD) include difficulties with balance, posture, speech, swallowing, and locomotion with freezing of gait, as well as axial rigidity. These axial symptoms impact negatively on quality of life for many patients, yet remain poorly understood. Dopaminergic treatments typically have little effect on the axial symptoms of PD, suggesting that disruptions in other neurotransmitter systems beyond the dopamine system may underlie these symptoms. The purpose of the present study was to examine the relationship between the axial symptoms of PD and GABA and glutamate levels quantified with magnetic resonance spectroscopy.Methods: The participant group included 20 patients with PD and 17 healthy control participants. Water-scaled GABA and Glx (glutamate + glutamine) concentrations were derived from GABA-edited MEGA-PRESS spectra acquired from the left basal ganglia and prefrontal cortex, and additional water-scaled Glx concentrations were acquired from standard PRESS spectra acquired from the pons. Spectra were analyzed with LCModel. The axial symptoms of PD were evaluated from subscales of the Unified Parkinson's Disease rating scale (MDS-UPDRS).Results: PD patients demonstrated significantly higher GABA levels in the basal ganglia, which correlated with the degree of gait disturbance. Basal ganglia Glx levels and prefrontal GABA and Glx levels did not differ significantly between patient and control groups, but within the PD group prefrontal Glx levels correlated negatively with difficulties turning in bed. Results from an exploratory subgroup analysis indicate that the associations between GABA, Glx, and axial symptoms scores are typically more prominent in akinetic-rigid patients than in tremor-dominant patients.Conclusion: Alterations in GABAergic and glutamatergic neurotransmission may contribute to some of the axial symptoms of PD

Exploring societal solidarity in the context of extreme prematurity

QUESTION: Extreme prematurity can result in long-term disabilities. Its impact on society is often not taken into account and deemed controversial. Our study examined attitudes of the Swiss population regarding extreme prematurity and people’s perspectives regarding the question of solidarity with disabled people. METHODS: We conducted a nationwide representative anonymous telephone survey with 1210 Swiss residents aged 18 years or older. We asked how people estimate their own personal solidarity, the solidarity of their social environment and the solidarity across the country with disabled persons. Spearman’s correlation calculations were used to assess if a correlation exists between solidarity and setting financial limits to intensive care and between solidarity and withholding neonatal intensive care. RESULTS: According to 36.0% of the respondents intensive medical care should not be withheld from extremely preterm infants, even if their chances for an acceptable quality of life were poor. For 28.8%, intensive care should be withheld from these infants, and 26.9% held an intermediate position depending on the situation. A total of 31.5% were against setting a financial limit to treatment of extremely preterm newborns with an uncertain future quality of life, 34.2% were in favour and 26.9% were deliberating. A majority (88.8%) considered their solidarity toward disabled people as substantial; the solidarity of their personal environment and of the society at large was estimated as high by 79.1% and 48.6%, respectively. CONCLUSIONS: The Swiss population expressed a high level of solidarity which may alleviate some pressure on parents and health care providers in the decision-making process in neonatal intensive care units. In addition, there was no relationship between solidarity and people’s willingness to pay for the care or withholding treatment of extremely preterm babies

The Genetics of Inherited Cholestatic Disorders in Neonates and Infants: Evolving Challenges

Many inherited conditions cause cholestasis in the neonate or infant. Next-generation sequencing methods can facilitate a prompt diagnosis in some of these cases; application of these methods in patients with liver diseases of unknown cause has also uncovered novel gene-disease associations and improved our understanding of physiological bile secretion and flow. By helping to define the molecular basis of certain cholestatic disorders, these methods have also identified new targets for therapy as well patient subgroups more likely to benefit from specific therapies. At the same time, sequencing methods have presented new diagnostic challenges, such as the interpretation of single heterozygous genetic variants. This article discusses those challenges in the context of neonatal and infantile cholestasis, focusing on difficulties in predicting variant pathogenicity, the possibility of other causal variants not identified by the genetic screen used, and phenotypic variability among patients with variants in the same genes. A prospective, observational study performed between 2010–2013, which sequenced six important genes (ATP8B1, ABCB11, ABCB4, NPC1, NPC2 and SLC25A13) in an international cohort of 222 patients with infantile liver disease, is given as an example of potential benefits and challenges that clinicians could face having received a complex genetic result. Further studies including large cohorts of patients with paediatric liver disease are needed to clarify the spectrum of phenotypes associated with, as well as appropriate clinical response to, single heterozygous variants in cholestasis-associated genes

Solidarität und Verantwortung in der Pandemie

Die Corona-Pandemie berührt weite Bereiche des gesellschaftlichen, wirtschaftlichen und politischen Lebens. Mit hoher Dringlichkeit stellt sich angesichts der Ressourcenknappheit die Forderung nach einer konkret gelebten Solidarität und verantwortungsvollen ­Koordination zwischen Behörden, Organisationen, Institutionen, Generationen und Individuen. Medizinethikerinnen und -ethiker der Schweiz formulieren dazu vier Postulate

Five-year experience of clinical ethics consultations in a pediatric teaching hospital

Our retrospective study presents and evaluates clinical ethics consultations (CECs) in pediatrics as a structure for implementing hospital-wide ethics. We performed a descriptive and statistical analysis of clinical ethics decision making and its implementation in pediatric CECs at Zurich University Children's Hospital. Ninety-five CECs were held over 5years for 80 patients. The care team reached a consensus treatment recommendation after one session in 75 consultations (89%) and on 82 of 84 ethical issues (98%) after two or more sessions (11 repeats). Fifty-seven CECs recommended limited treatment and 23 maximal treatment. Team recommendations were agreed outright by parents and/or patient in 59 of 73 consultations (81%). Initial dissensus yielded to explanatory discussion or repeat CEC in seven consultations (10%). In a further seven families (10%), no solution was found within the CEC framework: five (7%) required involvement of the child protection service, and in two families, the parents took their child elsewhere. Eventual team-parent/patient consensus was reached in 66 of 73 families (90%) with documented parental/patient decisions (missing data, n = 11). Patient preference was assessable in ten CECs. Patient autonomy was part of the ethical dilemma in only three CECs. The Zurich clinical ethics structure produced a 98% intra-team consensus rate in 95 CECs and reduced initial team-parent dissensus from 21 to 10%. Success depends closely on a standardized CEC protocol and an underlying institutional clinical ethics framework embodying a comprehensive set of transparently articulated values and opinions, with regular evaluation of decisions and their consequences for care teams and families

Five-year experience of clinical ethics consultations in a pediatric teaching hospital

Our retrospective study presents and evaluates clinical ethics consultations (CECs) in pediatrics as a structure for implementing hospital-wide ethics. We performed a descriptive and statistical analysis of clinical ethics decision making and its implementation in pediatric CECs at Zurich University Children's Hospital. Ninety-five CECs were held over 5years for 80 patients. The care team reached a consensus treatment recommendation after one session in 75 consultations (89%) and on 82 of 84 ethical issues (98%) after two or more sessions (11 repeats). Fifty-seven CECs recommended limited treatment and 23 maximal treatment. Team recommendations were agreed outright by parents and/or patient in 59 of 73 consultations (81%). Initial dissensus yielded to explanatory discussion or repeat CEC in seven consultations (10%). In a further seven families (10%), no solution was found within the CEC framework: five (7%) required involvement of the child protection service, and in two families, the parents took their child elsewhere. Eventual team-parent/patient consensus was reached in 66 of 73 families (90%) with documented parental/patient decisions (missing data, n = 11). Patient preference was assessable in ten CECs. Patient autonomy was part of the ethical dilemma in only three CECs. The Zurich clinical ethics structure produced a 98% intra-team consensus rate in 95 CECs and reduced initial team-parent dissensus from 21 to 10%. Success depends closely on a standardized CEC protocol and an underlying institutional clinical ethics framework embodying a comprehensive set of transparently articulated values and opinions, with regular evaluation of decisions and their consequences for care teams and families