Summary
Background
Proton pump inhibitors (PPIs) have a well‐established safety profile. However, concerns have been raised about a potential relationship between PPI‐induced hypergastrinaemia and ...the development of enterochromaffin‐like (ECL) cell hyperplasia, neuroendocrine tumours and gastric cancer during long‐term therapy.
Aim
To review the effects of long‐term PPI use on serum gastrin levels and gastric histopathology.
Methods
A systematic literature search was conducted in PubMed on 21 April 2015 to identify studies reporting the effects of long‐term (defined as >3 years) PPI use on gastrin levels and gastric histopathology.
Results
A total of 16 studies (1920 patients) met the inclusion criteria. During long‐term PPI therapy, mean gastrin levels rose to one to three times the upper limit of the normal range (~100 pg/mL), and an increased prevalence of ECL cell hyperplasia was observed (+7.8–52.0%). Helicobacter pylori‐positive patients had a significantly increased risk of developing ECL linear/micronodular hyperplasia compared with H. pylori‐negative patients OR: 2.45 (95% CI: 1.47–4.10), P = 0.0006; however, no evidence of neoplastic changes was found. The risk of corpus atrophy was markedly higher in H. pylori‐positive patients than in H. pylori‐negative patients OR: 11.45 (95% CI: 6.25–20.99), P < 0.00001. Not a single case of gastric adenocarcinoma was found.
Conclusions
Long‐term PPI therapy induced moderate hypergastrinaemia in most patients and an increased prevalence of ECL cell hyperplasia. H. pylori‐positive patients receiving long‐term PPI therapy were exposed to a higher risk of corpus atrophy than H. pylori‐negative patients. No neuroendocrine tumours or gastric cancers were found.
We present an improved version of a light curve model that is able to estimate the physical properties of different types of core-collapse supernovae that have double-peaked light curves and do so in ...a quick and efficient way. The model is based on a two-component configuration consisting of a dense inner region and an extended low-mass envelope. Using this configuration, we estimate the initial parameters of the progenitor by fitting the shape of the quasi-bolometric light curves of 10 SNe, including Type IIP and IIb events, with model light curves. In each case we compare the fitting results with available hydrodynamic calculations and also match the derived expansion velocities with the observed ones. Furthermore, we compare our calculations with hydrodynamic models derived by the SNEC code and examine the uncertainties of the estimated physical parameters caused by the assumption of constant opacity and the inaccurate knowledge of the moment of explosion.
The focus of our research is the examination of Hermitian curves over finite fields, specifically concentrating on places of degree three and their role in constructing Hermitian codes. We begin by ...studying the structure of the Riemann-Roch space associated with these degree-three places, aiming to determine essential characteristics such as the basis. The investigation then turns to Hermitian codes, where we analyze both functional and differential codes of degree-three places, focusing on their parameters and automorphisms. In addition, we explore the study of subfield subcodes and trace codes, determining their structure by giving lower bounds for their dimensions. This presents a complex problem in coding theory. Based on numerical experiments, we formulate a conjecture for the dimension of some subfield subcodes of Hermitian codes. Our comprehensive exploration seeks to deepen the understanding of Hermitian codes and their associated subfield subcodes related to degree-three places, thus contributing to the advancement of algebraic coding theory and code-based cryptography.
The assessment of creep damage in steels employed in the power generation industry is usually carried out by means of replica metallography, but the several shortcomings of this method have prompted ...a search for alternative or complementary non-destructive techniques, ranging from ultrasonic to electromagnetic methods, hardness measurements and nuclear techniques. A critical review of the main results obtained to date in the secondary and tertiary stages of creep is presented in this paper, and the advantages and disadvantages of each method are discussed. Ultrasonic and potential drop techniques appear to be the most promising, but further research is needed before they are fully mature for deployment in the field.
We study the tree-tensor-network-state (TTNS) method with variable tensor orders for quantum chemistry. TTNS is a variational method to efficiently approximate complete active space (CAS) ...configuration interaction (CI) wave functions in a tensor product form. TTNS can be considered as a higher order generalization of the matrix product state (MPS) method. The MPS wave function is formulated as products of matrices in a multiparticle basis spanning a truncated Hilbert space of the original CAS-CI problem. These matrices belong to active orbitals organized in a one-dimensional array, while tensors in TTNS are defined upon a tree-like arrangement of the same orbitals. The tree-structure is advantageous since the distance between two arbitrary orbitals in the tree scales only logarithmically with the number of orbitals N, whereas the scaling is linear in the MPS array. It is found to be beneficial from the computational costs point of view to keep strongly correlated orbitals in close vicinity in both arrangements; therefore, the TTNS ansatz is better suited for multireference problems with numerous highly correlated orbitals. To exploit the advantages of TTNS a novel algorithm is designed to optimize the tree tensor network topology based on quantum information theory and entanglement. The superior performance of the TTNS method is illustrated on the ionic-neutral avoided crossing of LiF. It is also shown that the avoided crossing of LiF can be localized using only ground state properties, namely one-orbital entanglement.
A numerical algorithm is proposed to construct efficient quadrature rules for trimmed isogeometric elements of arbitrary shape and topology as part of the standard finite element preprocessing step. ...The constructed integration rule is unique to an element and it is considered to be optimal in the sense that the final quadrature points and weights satisfy the moment fitting equations within the trimmed domain up to a predefined tolerance. The resulting quadrature points are in the interior of the trimmed domain and the positivity of the weights is preserved. The accuracy and efficiency of the quadrature scheme are assessed and compared to traditionally employed integration techniques. Results indicate that the proposed integration rules are more precise and inhibit the proliferation of quadrature points observed in competing approaches. Selected problems of elastostatics, elastodynamics, and elasto-plastic dynamics are used to further demonstrate the validity and efficacy of the method.
•A numerical algorithm is proposed for the design of optimal quadrature rules on trimmed isogeometric elements.•The quadrature design scheme imposes no restrictions on the shape or topology of the trimmed element domain.•The quadrature points are in the interior of the trimmed domain and positivity of the weights is preserved.•Integration rules designed by the proposed algorithm are found to outperform competing techniques in terms of accuracy and efficiency.
Highlights ► VAChT genomic DNA is replicated in commercial B6. eGFPChAT mice. ► VAChT mRNA expression was elevated in B6. eGFPChAT septal tissue versus B6 controls. ► VAChT protein was enhanced in ...the hippocampus and striatum of B6. eGFPChAT mice. ► B6. eGFPChAT mice exhibit enhanced hippocampal acetylcholine release. ► Increasing VAChT expression is sufficient to elevate acetylcholine release.
The present study investigated the role of adaptability in helping high school students navigate their online learning during a period of COVID-19 that entailed fully or partially remote online ...learning. Drawing on Job Demands-Resources theory and data from a sample of 1,548 Australian high school students in nine schools, we examined the role of adaptability in predicting students’ online learning self-efficacy in mathematics and their end of year mathematics achievement. It was found that beyond the effects of online learning demands, online and parental learning support, and background attributes, adaptability was significantly associated with higher levels of online learning self-efficacy and with gains in later achievement; online learning self-efficacy was also significantly associated with gains in achievement—and significantly mediated the relationship between adaptability and achievement. These findings confirm the role of adaptability as an important personal resource that can help students in their online learning, including through periods of remote instruction, such as during COVID-19.
The microstructure, texture and mechanical behavior of two wrought ZK60 magnesium alloys were investigated by tensile test and shear punch test (SPT). The samples processed by hot rolling and the ...combination of hot rolling and sheet extrusion techniques. The mechanical properties of the alloys correlated to the microstructural characteristics and the texture. Microstructural analysis showed that extrusion transformed the equiaxed coarse grain structure of the rolled sample with an average grain size of 68 μm to a bimodal structure including very fine dynamically recrystallized (DRX) grains, having an average grain size of ∼2.8, and large elongated deformed grains. The sheet extrusion process improved the tensile yield stress, the ultimate tensile strength, the shear strength, and the tensile elongation to failure. The strength enhancement was attributed to the finer grain size and the change of the volume fraction of the secondary phase particles. It was demonstrated that extrusion could improve both strength and ductility at room temperature in wrought ZK60 alloy. Although the tensile ductility improved after extrusion, it was shown that deformability in SPT remains unchanged after extrusion. Microstructural observations show that in SPT the positive effect of the grain refinement on the ductility was compensated by the hindering effect of Mg4Zn7 particles on the glide of <c+a> pyramidal dislocations. This slip is a dominant mechanism of deformation during SPT due to the basal texture.
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