Brauer-Thrall for totally reflexive modules over local rings of higher dimension

Let $R$ be a commutative Noetherian local ring. Assume that $R$ has a pair $\{x,y\}$ of exact zerodivisors such that $\dim R/(x,y)\ge2$ and all totally reflexive $R/(x)$-modules are free. We show that the first and second Brauer--Thrall type theorems hold for the category of totally reflexive $R$-modules. More precisely, we prove that, for infinitely many integers $n$, there exists an indecomposable totally reflexive $R$-module of multiplicity $n$. Moreover, if the residue field of $R$ is infinite, we prove that there exist infinitely many isomorphism classes of indecomposable totally reflexive $R$-modules of multiplicity $n$.Comment: to appear in Algebras and Representation Theor

Circulating Acylcarnitines Associated with Hypertrophic Cardiomyopathy Severity: an Exploratory Cross-Sectional Study in MYBPC3 Founder Variant Carriers

Hypertrophic cardiomyopathy (HCM) is a relatively common genetic heart disease characterised by myocardial hypertrophy. HCM can cause outflow tract obstruction, sudden cardiac death and heart failure, but severity is highly variable. In this exploratory cross-sectional study, circulating acylcarnitines were assessed as potential biomarkers in 124 MYBPC3 founder variant carriers (59 with severe HCM, 26 with mild HCM and 39 phenotype-negative [G + P-]). Elastic net logistic regression identified eight acylcarnitines associated with HCM severity. C3, C4, C6-DC, C8:1, C16, C18 and C18:2 were significantly increased in severe HCM compared to G + P-, and C3, C6-DC, C8:1 and C18 in mild HCM compared to G + P-. In multivariable linear regression, C6-DC and C8:1 correlated to log-transformed maximum wall thickness (coefficient 5.01, p = 0.005 and coefficient 0.803, p = 0.007, respectively), and C6-DC to log-transformed ejection fraction (coefficient -2.50, p = 0.004). Acylcarnitines seem promising biomarkers for HCM severity, however prospective studies are required to determine their prognostic value

BIO FOr CARE: biomarkers of hypertrophic cardiomyopathy development and progression in carriers of Dutch founder truncating MYBPC3 variants-design and status

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is the most prevalent monogenic heart disease, commonly caused by truncating variants in the MYBPC3 gene. HCM is an important cause of sudden cardiac death; however, overall prognosis is good and penetrance in genotype-positive individuals is incomplete. The underlying mechanisms are poorly understood and risk stratification remains limited. AIM: To create a nationwide cohort of carriers of truncating MYBPC3 variants for identification of predictive biomarkers for HCM development and progression. METHODS: In the multicentre, observational BIO FOr CARe (Identification of BIOmarkers of hypertrophic cardiomyopathy development and progression in Dutch MYBPC3 FOunder variant CARriers) cohort, carriers of the c.2373dupG, c.2827C > T, c.2864_2865delCT and c.3776delA MYBPC3 variants are included and prospectively undergo longitudinal blood collection. Clinical data are collected from first presentation onwards. The primary outcome constitutes a composite endpoint of HCM progression (maximum wall thickness ≥ 20 mm, septal reduction therapy, heart failure occurrence, sustained ventricular arrhythmia and sudden cardiac death). RESULTS: So far, 250 subjects (median age 54.9 years (interquartile range 43.3, 66.6), 54.8% male) have been included. HCM was diagnosed in 169 subjects and dilated cardiomyopathy in 4. The primary outcome was met in 115 subjects. Blood samples were collected from 131 subjects. CONCLUSION: BIO FOr CARe is a genetically homogeneous, phenotypically heterogeneous cohort incorporating a clinical data registry and longitudinal blood collection. This provides a unique opportunity to study biomarkers for HCM development and prognosis. The established infrastructure can be extended to study other genetic variants. Other centres are invited to join our consortium

Relativistic effects in the electrodisintegration of deuterium

The structure function R(LT) and the cross-section asymmetry A(phi) with respect to the direction of the momentum transfer in the reaction H-2(e, e'p) have been measured at a four-momentum transfer squared of 0.2 (GeV/c)(2), for missing momenta between 160 and 220 MeV/c at an invariant mass of 1050 MeV. For a proper description of these data calculations that include a relativistic form of the nucleon current operator are favoured. The absolute 2H(e, e'p) cross-section data favour a covariant calculation over non-relativistic calculations with relativistic corrections

Deuteron electrodisintegration at high missing momenta

The reaction (2)H(e, e'p) has been studied at an invariant mass W of 1050 MeV, i.e. well below the Delta(1232) resonance, Cross sections have been obtained at values of Q(2), the four-momentum transfer squared, of 0.10, 0.20, and 0.28 (GeV/c)(2), covering a missing-momentum range from 150 to 700 MeV/c. The data are compared to the results of covariant calculations of Tjon, and the results of calculations based on a Schrodinger formalism due to Laget and the Mainz group, respectively. The data are well described by the calculations of the Mainz group, whereas they are underestimated by Tjon's calculations at high missing momenta. The calculations of Laget, on the other hand, overestimate the data at low missing momenta, but give a good account of the data at high missing momenta. More detailed considerations reveal that the Delta(1232) contributions are dominant at high missing momenta. However, the lacking Delta(1232) contribution in Tjon's calculations is not enough to explain the large discrepancy between his calculation and the present (2)H(e, e'p) data at high missing momentum. Probably the deuteron wave function employed in the covariant calculations has a D-state contribution that is too small

Deuteron electrodisintegration in the Delta-resonance region

The differential cross section and the transverse-transverse interference structure function for the reaction H-2(e,e'p)n have been determined at an np invariant mass of 2.16 GeV. The data, covering a 40 degrees range in the proton emission angle, indicate that Delta excitation and subsequent N Delta interaction is the dominant reaction mechanism. Calculations performed within an N Delta coupled-channel approach reproduce the cross section data, but underestimate the f(TT) results by 30 to 40 percent

Proton detection with large-acceptance scintillator detection systems in electron-scattering environments

Two highly segmented plastic-scintillator arrays have been developed for proton detection in electron scattering experiments. The detectors subtend solid angles of 225 and 550 msr and cover energy ranges of 50-225 and 25-165 MeV, respectively. The charge and arrival time of each photomultiplier signal are digitized by flash ADCs and temporarily stored in a dual-port memory. The readout parameters are computer controlled, tuned, and monitored. These detectors have been employed in (e, e'p) and (e, e'pp) experiments for proton emission angles greater than 30 degrees and for luminosities up to 10(36) nucleons cm(-2) s(-1). The singles counting rates in the scintillator elements of the first layers were about 0.5 x 10(6) particles s(-1) and the trigger rate 1 MHz. The measured resolution in the excitation energy and timing spectra are 2.7% and 0.7 ns, respectively. (C) 1999 Elsevier Science B.V. All rights reserved

Search for Nucleon-nucleon Correlations in the Proton Spectral-function of Pb-208

Cross sections for the reaction Pb-208 (e,e'p) have been measured with the continuous electron beam from the Amsterdam Pulse-Stretcher facility at NIKHEF-K. The spectral function has been extracted for protons with initial momenta of 300 to 500 MeV/c and binding energies up to 26 MeV. The data are compared to calculations with and without inclusion of nucleon-nucleon correlations. Mean-field predictions significantly underestimate the data and the discrepancy increases with binding energy. For transitions to the valence states the discrepancy is removed by introducing long-range correlations. Above the two-nucleon emission threshold long-range and short-range correlations reduce the discrepancy, but are insufficient to fully account for the measured strength

Deuteron electrodisintegration at high missing momenta

The reaction (2)H(e, e'p) has been studied at an invariant mass W of 1050 MeV, i.e. well below the Delta(1232) resonance, Cross sections have been obtained at values of Q(2), the four-momentum transfer squared, of 0.10, 0.20, and 0.28 (GeV/c)(2), covering a missing-momentum range from 150 to 700 MeV/c. The data are compared to the results of covariant calculations of Tjon, and the results of calculations based on a Schrodinger formalism due to Laget and the Mainz group, respectively. The data are well described by the calculations of the Mainz group, whereas they are underestimated by Tjon's calculations at high missing momenta. The calculations of Laget, on the other hand, overestimate the data at low missing momenta, but give a good account of the data at high missing momenta. More detailed considerations reveal that the Delta(1232) contributions are dominant at high missing momenta. However, the lacking Delta(1232) contribution in Tjon's calculations is not enough to explain the large discrepancy between his calculation and the present (2)H(e, e'p) data at high missing momentum. Probably the deuteron wave function employed in the covariant calculations has a D-state contribution that is too small