The paper examines the evolvements in the global value chain positions of the Central and Eastern European (CEE) countries. This approach enables us to reveal both economic and sector-level ...structural changes in the economic catching-up process. To study the structural patterns, we developed a modified smile curve framework that combines the value-added ratio and upstreamness index. Data were derived from the WIOD database from 2000 to 2014. By undergoing a significant catch-up in the last decades, CEE countries have shown considerably different patterns in their evolvements of GVC positions. Regarding the economy level, we concluded that leading economies can be described by a “U”-shaped smile curve over the period. There are two further dominant patterns that have become widespread among the CEE countries. Until 2014, the most common structure is marked by a “/” shape, which reflects an upstream-weak economy (e.g., BGR 2000; HUN 2000; LVA 2014). The second most common structure is marked by an inverted “U” shape (“^” shape), which denotes a manufacturing-heavy economy (e.g., EST 2000; POL 2000; HUN 2014; POL 2014). There is no significant difference in the added value ratio of the manufacturing sectors compared to the western countries.Implications for Central European audience: Typically, the CEE countries are shifting towards supplier positions and sectors with less complex output, resulting in the flattening and twisting of the “U” shape. While most studies focus on a single sector or region, this study involves many sectors and many countries that provide a real global context, thus extending the GVC-related empirical studies concerning the CEER. To further facilitate the significant catching-up process, the upstream-weak economies should develop their structure in a way that less simple and specialised production processes are done at a high rate in any sector. Heavy manufacturing should elaborate market connections and develop connections to customers. It alerts that a transition is required from extensive to intensive and knowledge-based developments.
The reaction Be(p7,γ)8B plays an important role in the Sun, where it determines the high energy component of the solar neutrino spectrum. The importance of this reaction triggered several experiments ...over the last decades. A combined analysis of their results produces an overall consistent picture for the energy dependence of the cross section, while an inflation of the quoted uncertainties is needed to accommodate the observed discrepancy in the absolute scale of the different data sets. The origin of this discrepancy needs to be understood for a reliable estimate of the astrophysical rate of Be(p7,γ)8B and its uncertainty. In addition, there is a question about possible common systematic effects, considering that all measurements performed so far share the same experimental approach, i.e. an intense proton beam impinging on a Be7 radioactive target. A direct measurement using a radioactive Be7 ion beam on a pure hydrogen gas target has been since long envisioned as a way to improve the situation. First attempts showed the feasibility of an experiment based on the use of a recoil mass separator to collect reaction products with high efficiency, but failed to reach a useful statistical significance because of the low beam intensity. Here we present the results obtained using the intense Be7 beam available at the Tandem Accelerator Laboratory at CIRCE, University of Campania, Italy coupled to the recoil mass separator ERNA in the energy range Ecm=367 to 812 keV. Our results are compatible only with a part of previous measurements, in particular those indicating a low value of the astrophysical S-factor at zero energy S17, thus exacerbating the discrepancy between existing measurements. The analysis of our data together with the results of previous data provides an estimate S17(0)=20.0±0.8 eV⋅b, where systematic uncertainties are inflated to obtain a statistically compatible data set.
A simple and low-cost, DIY-type, Arduino-driven experiment is presented for the study of friction and measurement of the friction coefficient, using a conductive rubber cord as a force sensor. It is ...proposed for high-school or college/university-level students. We strongly believe that it is worthwhile planning, designing and performing Arduino and compatible sensor-based experiments in physics class in order to ensure a better understanding of phenomena, develop theoretical knowledge and multiple experimental skills.
Off-energy-shell effects in p - p scattering have been investigated at p - p relative energies from 600 down to 80 keV applying the Trojan horse method (THM) to the p + d --> p + p + n reaction at 5 ...MeV. In contrast with the on-energy-shell case, no Coulomb-nuclear interference minimum has been found in the extracted THM p - p cross section, due to the suppression of the Coulomb amplitude as predicted by the half-off-energy shell calculations. This hypothesis is strengthened by the agreement between THM p - p data and calculated on-energy-shell n + n, n + p and nuclear p + p cross sections.
Abstract
The
$$^{27}\hbox {Al}(\hbox {p},\alpha )^{24}\hbox {Mg}$$
27
Al
(
p
,
α
)
24
Mg
reaction, which drives the destruction of
$$^{27}$$
27
Al and the production of
$$^{24}\hbox {Mg}$$
24
Mg
in ...stellar hydrogen burning, has been investigated via the Trojan Horse Method (THM), by measuring the
$$^2\hbox {H}(^{27}\hbox {Al},\alpha ^{24}\hbox {Mg})\hbox {n}$$
2
H
(
27
Al
,
α
24
Mg
)
n
three-body reaction. The experiment covered a broad energy range (
$$E_\mathrm{c.m.}\le \,1.5\,\hbox {MeV}$$
E
c
.
m
.
≤
1.5
MeV
), aiming to investigate those of interest for astrophysics. The results confirm the THM as a valuable technique for the experimental study of fusion reactions at very low energies and suggest the presence of a rich pattern of resonances in the energy region close to the Gamow window of stellar hydrogen burning (70–120 keV), with potential impact on astrophysics. To estimate such an impact a second run of the experiment is needed, since the background due the three-body reaction hampered to collect enough data to resolve the resonant structures and extract the reaction rate.
The
27
Al
(
p
,
α
)
24
Mg
reaction, which drives the destruction of
27
Al and the production of
24
Mg
in stellar hydrogen burning, has been investigated via the Trojan Horse Method (THM), by ...measuring the
2
H
(
27
Al
,
α
24
Mg
)
n
three-body reaction. The experiment covered a broad energy range (
E
c
.
m
.
≤
1.5
MeV
), aiming to investigate those of interest for astrophysics. The results confirm the THM as a valuable technique for the experimental study of fusion reactions at very low energies and suggest the presence of a rich pattern of resonances in the energy region close to the Gamow window of stellar hydrogen burning (70–120 keV), with potential impact on astrophysics. To estimate such an impact a second run of the experiment is needed, since the background due the three-body reaction hampered to collect enough data to resolve the resonant structures and extract the reaction rate.
The electron screening effect in the d(d,p)t reaction has been studied for 29 deuterated metals and 5 deuterated insulators/semiconductors. As compared to measurements performed with a gaseous D2 ...target, a large effect has been observed in the metals V, Nb, and Ta, which belong to group 5 of the periodic table, as well as in Cr, Mo, and W (group 6), Mn and Re (group 7), Fe and Ru (group 8), Co, Rh, and Ir (group 9), Ni, Pd, and Pt (group 10), Zn and Cd (group 12), and Sn and Pb (group 14). In contrast, a comparatively small effect is found in group 4 (Ti, Zr, Hf), group 11 (Cu, Ag, Au), group 13 (B, Al), for the insulator BeO, and for the semiconductors C, Si, and Ge. An explanation of this apparently novel feature of the periodic table is missing.
Chronic lymphocytic leukemia (CLL) is an indolent B cell non-Hodgkin lymphoma (NHL) that may transform into diffuse large B cell lymphoma (DLBL). This transformation is referred to as Richter's ...syndrome or transformation. To analyze whether microsatellite instability (MSI) and DNA mismatch repair defects are associated with Richter's transformation, we have performed microsatellite analysis, mutational analysis of hMLH1 and hMSH2 genes and methylation status analysis of CpG island of the hMLH1 promoter on serial biopsy specimens from 19 patients with CLL. Ten cases of CLL showed no histologic alteration in the second biopsy, and nine cases of CLL underwent morphologic transformation to DLBL in the second biopsy. Using eight microsatellite loci, high level of MSI was associated with Richter's transformation in four cases of CLL, but none of the CLLs displayed this level of MSI without transformation. Mutations of the hMLH1 or hMSH2 genes were not detected in any of the lymphoma samples. In five cases of Richter's transformation the hMLH1 promoter was hypermethylated in both CLL and DLBL samples. Hypermethylation of the hMLH1 promoter associated with high-level of MSI in four cases, and low-level of MSI in one case. These results suggest that in certain cases of Richter's transformation the DNA mismatch-repair defect-initiated genetic instability may play a role in tumor progression.
Patients with chronic lymphocytic leukemia (CLL) may develop diffuse large B-cell lymphoma (DLBL), also known as Richter's syndrome. Mutational status of immunoglobulin (Ig) heavy-chain variable ...region (VH) genes have prognostic impact in CLL. Patients with mutated VH genes have a stable disease, whereas patients with unmutated VH gene have more aggressive disease. The mutational status of CLLs that transform to DLBL is unknown. To reveal whether Richter's syndrome occurs in CLLs with mutated or unmutated VH genes, we have performed mutational analysis on serial specimens from eight patients. CLL and DLBL tumorclones were identical in five cases and they were different in three cases. Six CLLs expressed unmutated and two cases expressed mutated VH genes. In five of the six unmutated CLLs, the DLBL clones evolved from CLL tumorclones and the VH genes expressed by DLBLs were also unmutated. In one unmutated and two mutated CLLs, the DLBLs expressed mutated VH genes, but in these three cases the DLBL tumorclones developed as independent secondary neoplasm. These results suggest that Richter's syndrome may develop in both mutated or unmutated CLLs, but clonal transformation of CLL to DLBL occur only in the unmutated subgroup of CLL.
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