On the geometrization of matter by exotic smoothness

In this paper we discuss the question how matter may emerge from space. For that purpose we consider the smoothness structure of spacetime as underlying structure for a geometrical model of matter. For a large class of compact 4-manifolds, the elliptic surfaces, one is able to apply the knot surgery of Fintushel and Stern to change the smoothness structure. The influence of this surgery to the Einstein-Hilbert action is discussed. Using the Weierstrass representation, we are able to show that the knotted torus used in knot surgery is represented by a spinor fulfilling the Dirac equation and leading to a mass-less Dirac term in the Einstein-Hilbert action. For sufficient complicated links and knots, there are "connecting tubes" (graph manifolds, torus bundles) which introduce an action term of a gauge field. Both terms are genuinely geometrical and characterized by the mean curvature of the components. We also discuss the gauge group of the theory to be U(1)xSU(2)xSU(3).Comment: 30 pages, 3 figures, svjour style, complete reworking now using Fintushel-Stern knot surgery of elliptic surfaces, discussion of Lorentz metric and global hyperbolicity for exotic 4-manifolds added, final version for publication in Gen. Rel. Grav, small typos errors fixe

The Oregon Experiment — Effects of Medicaid on Clinical Outcomes

Background: Despite the imminent expansion of Medicaid coverage for low-income adults, the effects of expanding coverage are unclear. The 2008 Medicaid expansion in Oregon based on lottery drawings from a waiting list provided an opportunity to evaluate these effects. Methods: Approximately 2 years after the lottery, we obtained data from 6387 adults who were randomly selected to be able to apply for Medicaid coverage and 5842 adults who were not selected. Measures included blood-pressure, cholesterol, and glycated hemoglobin levels; screening for depression; medication inventories; and self-reported diagnoses, health status, health care utilization, and out-of-pocket spending for such services. We used the random assignment in the lottery to calculate the effect of Medicaid coverage. Results: We found no significant effect of Medicaid coverage on the prevalence or diagnosis of hypertension or high cholesterol levels or on the use of medication for these conditions. Medicaid coverage significantly increased the probability of a diagnosis of diabetes and the use of diabetes medication, but we observed no significant effect on average glycated hemoglobin levels or on the percentage of participants with levels of 6.5% or higher. Medicaid coverage decreased the probability of a positive screening for depression (−9.15 percentage points; 95% confidence interval, −16.70 to −1.60; P=0.02), increased the use of many preventive services, and nearly eliminated catastrophic out-of-pocket medical expenditures. Conclusions: This randomized, controlled study showed that Medicaid coverage generated no significant improvements in measured physical health outcomes in the first 2 years, but it did increase use of health care services, raise rates of diabetes detection and management, lower rates of depression, and reduce financial strain.United States. Dept. of Health and Human Services. Office of the Assistant Secretary for Planning and EvaluationCalifornia HealthCare FoundationNational Institute on Aging (P30AG012810)National Institute on Aging (RC2AGO36631)National Institute on Aging (R01AG0345151)John D. and Catherine T. MacArthur FoundationRobert Wood Johnson FoundationAlfred P. Sloan FoundationSmith Richardson FoundationUnited States. Social Security Administration (5 RRC 08098400-03-00, to the National Bureau of Economic Research as part of the Retirement Research Consortium of the Social Security Administration)Centers for Medicare & Medicaid Services (U.S.

Negatively Charged Excitons and Photoluminescence in Asymmetric Quantum Well

We study photoluminescence (PL) of charged excitons ($X^-$) in narrow asymmetric quantum wells in high magnetic fields B. The binding of all $X^-$ states strongly depends on the separation $\delta$ of electron and hole layers. The most sensitive is the ``bright'' singlet, whose binding energy decreases quickly with increasing $\delta$ even at relatively small B. As a result, the value of B at which the singlet--triplet crossing occurs in the $X^-$ spectrum also depends on $\delta$ and decreases from 35 T in a symmetric 10 nm GaAs well to 16 T for $\delta=0.5$ nm. Since the critical values of $\delta$ at which different $X^-$ states unbind are surprisingly small compared to the well width, the observation of strongly bound $X^-$ states in an experimental PL spectrum implies virtually no layer displacement in the sample. This casts doubt on the interpretation of PL spectra of heterojunctions in terms of $X^-$ recombination

Towards Formalizing Non-monotonic Reasoning in Physics: Logical Approach Based on Physical Induction and Its Relation to Kolmogorov Complexity

To formalize some types of non-monotonic reasoning in physics, researchers have proposed an approach based on Kolmogorov complexity. Inspired by Vladimir Lifschitz\u27s belief that many features of reasoning can be described on a purely logical level, we show that an equivalent formalization can be described in purely logical terms: namely, in terms of physical induction. One of the consequences of this formalization is that the set of not-abnormal states is (pre-)compact. We can therefore use Lifschitz\u27s result that when there is only one state that satisfies a given equation (or system of equations), then we can algorithmically find this state. In this paper, we show that this result can be extended to the case of approximate uniqueness

A multi-center study on the attitudes of Malaysian emergency health care staff towards allowing family presence during resuscitation of adult patients

BACKGROUND The practice of allowing family members to witness on-going active resuscitation has been gaining ground in many developed countries since it was first introduced in the early 1990s. In many Asian countries, the acceptability of this practice has not been well studied. AIM We conducted a multi-center questionnaire study to determine the attitudes of health care professionals in Malaysia towards family presence to witness ongoing medical procedures during resuscitation. METHODS Using a bilingual questionnaire (in Malay and English language), we asked our respondents about their attitudes towards allowing family presence (FP) as well as their actual experience of requests from families to be allowed to witness resuscitations. Multiple logistic regression was used to analyze the association between the many variables and a positive attitude towards FP. RESULTS Out of 300 health care professionals who received forms, 270 responded (a 90% response rate). Generally only 15.8% of our respondents agreed to allow relatives to witness resuscitations, although more than twice the number (38.5%) agreed that relatives do have a right to be around during resuscitation. Health care providers are significantly more likely to allow FP if the procedures are perceived as likely to be successful (e.g., intravenous cannulation and blood taking as compared to chest tube insertion). Doctors were more than twice as likely as paramedics to agree to FP (p-value = 0.002). This is probably due to the Malaysian work culture in our health care systems in which paramedics usually adopt a 'follow-the-leader' attitude in their daily practice. CONCLUSION The concept of allowing FP is not well accepted among our Malaysian health care providers

Classical Optimal Replacement Strategies Revisited

This paper considers the generalization of the classical optimal age replacement strategy to the case when the system's output is modelled by the decreasing deterministic function. This function describes an additional source of system's deterioration with time. We derive and analyze the long-run expected cost per unit of time and consider the corresponding optimal replacement problem. Our results show that additional source of degradation decreases the optimal replacement time as compared with the case without output or with a constant in time output. Furthermore, the optimal replacement time can now exist and be finite when the failure time of our system is described by the exponential, non-aging distribution. The cases of periodic replacement and of stochastic output are also considered and analyzed. Some simple examples illustrating our results are given

Study on Incentives for Glaucoma Medication Adherence (SIGMA): Study protocol for a randomized controlled trial to increase glaucoma medication adherence using value pricing

10.1186/s13063-016-1459-1Trials17131

Regeneration of Alkanolamine Solutions in Membrane Contactor Based on Novel Polynorbornene

For the first time, a novel highly permeable glassy polymer, addition poly[bis(trimethylsilyl)tricyclononene] (PBTMST), was proposed for its use in a gas-liquid membrane contactor for the regeneration of CO2 absorption liquids (desorption of CO2). This membrane material possesses a good chemical stability and high barrier properties for a number of alkanolmines (30 wt% solutions of MEA, DEA, MDEA, AMP, DEAE or AEAE) under typical regeneration conditions (T = 100°C). Studies on gas transport properties of PBTMST (100°C and 1-40 bar) show that permeability coefficients of oxygen, nitrogen and carbon dioxide initially tend to decrease, and then level off after first 6-8 hours of operation. This behavior can be explained by partial relaxation of the free-volume structure of PBTMST, no chemical degradation of polymer material at high temperature was confirmed by IR analysis. At the same time, this membrane material preserves high gas permeability coefficients which are higher than those of conventional materials used in the membrane contactors. Gas-liquid membrane contactor based on dense PBTMST membrane shows a good, stable performance; particularly, CO2 loading in diethanolamine solution (30 wt%) can be reduced for 0.05-0.34 mole/mole by single pass through the membrane desorber at 100°C and elevated pressure. It seems that desorption rate here is mainly controlled by liquid phase because decreasing of membrane thickness by 50% (from 31 to 21 μm) leads to improvement of DEA regeneration only by 1.5-8.5%