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The optoelectronic properties of two layered copper oxyselenide compounds, with nominal composition Sr2ZnO2Cu2Se2 and Ba2ZnO2Cu2Se2, have been investigated to determine their suitability as p-type conductors. The structure, band gaps and electrical conductivity of pristine and alkali-metal-doped samples have been determined. We find that the strontium-containing compound, Sr2ZnO2Cu2Se2, adopts the expected tetragonal Sr2Mn3SbO2 structure with I4/mmm symmetry, and has a band gap of 2.16 eV, and a room temperature conductivity of 4.8 × 10−1 S cm−1. The conductivity of the compound could be increased to 4.2 S cm−1 when sodium doped to a nominal composition of Na0.1Sr1.9ZnO2Cu2Se2. In contrast, the barium containing material was found to have a small zinc oxide deficiency, with a sample dependent compositional range of Ba2Zn1−xO2−xCu2Se2 where 0.01 < x < 0.06, as determined by single crystal X-ray diffraction and powder neutron diffraction. The barium-containing structure could also be modelled using the tetragonal I4/mmm structure, but significant elongation of the oxygen displacement ellipsoid along the Zn–O bonds in the average structure was observed. This indicated that the oxide ion position was better modelled as a disordered split site with a displacement to change the local zinc coordination from square planar to linear. Electron diffraction data confirmed that the oxide site in Ba2Zn1−xO2−xCu2Se2 does not adopt a long range ordered arrangement, but also that the idealised I4/mmm structure with an unsplit oxide site was not consistent with the extra reflections observed in the electron diffractograms. The band gap and conductivity of Ba2Zn1−xO2−xCu2Se2 were determined to be 2.22 eV and 2.0 × 10−3 S cm−1 respectively. The conductivity could be increased to 1.5 × 10−1 S cm−1 with potassium doping in K0.1Ba1.9Zn1−xO2−xCu2Se2. Hall measurements confirmed that both materials were p-type conductors with holes as the dominant charge carriers. [ABSTRACT FROM AUTHOR]

This study investigates the causal relationship between foreign direct investment (FDI) and its determinants in selected Southeast Asian countries, including China, Vietnam, Singapore, Malaysia, Indonesia, Thailand, and the Philippines, from 1990 to 2021. The determinants include infrastructure investment, economic freedom, human development, and economic growth. We examine these FDI determinants' short- and long-run dynamics by employing the Johansen cointegration technique and the Vector Error Correction Model (VECM). The empirical findings reveal varying longterm relationships between the FDI determinants across nations. Additionally, this study establishes the short-run causality between FDI and its determinants in these countries. The study advocates prioritising good governance and robust institutions in the context of policy development. In terms of regulatory framework, policymakers are urged to enhance economic liberalisation, invest in infrastructure, and develop human resources to promote FDI. By exploring these causal linkages, this study contributes to the literature, particularly in the context of Asia. [ABSTRACT FROM AUTHOR]

This review article reflects on thirty years of FDI-dependent development in Central and Eastern European regions (with a special emphasis on the Visegrad countries). The modernisation potential of FDI-led European integration is examined from a critical and comparative perspective. The authors argue that the FDI-led “Dependent Market Economy” (DME) model has fallen short of its anticipated modernisation potential, while other, potentially lucrative development alternatives have been neglected. While early-stage benefits were considerable, the development model now faces signs of exhaustion and an increasing number of contradictions. The paper builds on previous original research by the authors, as well as a review of international academic literature to describe the limitations and trade-offs of the DME development model, followed by an overview of three alternate growth paths for the future. In the macro-level perspective, it is argued that long-term catching-up rates across Central and Eastern Europe over 30 years have been limited, and signs of slowdown are increasingly apparent. Likewise, FDI does not seem to contribute significantly to domestic capital accumulation. On the micro-economic and regional levels, limited income effects are coupled with intangible risks and trade-offs. Strengthened socio-economic and territorial disparities ultimately pose problems for both metropolitan core regions and peripheries, while low capital embeddedness and limited spillovers denote weak territorial integration. It I advanced that the DME model may exacerbate future structural crises and exogenous shocks, and finally, that a development model dependent on exogenous capital structures shows curtailed capability to explore, learn, and benefit from beneficial growth opportunities. The paper makes the case that, while the DME model cannot be realistically dismantled in the foreseeable future without considerable risk to the CEE economies, a comprehensive diversification agenda should seek to gradually reduce its risks and foster alternate sources of growth. Embedding foreign capital into local economic networks represents one possible compromise, coupled with growing supplier networks and anchoring value creation in business services as well as innovation and R&D activities. However, alternate sources of development are also to be explored. The new revival of industrial policies in Europe and across the world opens opportunities before previously ‘inconceivable’ state-led development initiatives, including support for the emergence of new national champions. Last but not least, a strengthening domestic SME sector with competitive medium-sized enterprises and locally embedded production networks should serve to strengthen entrepreneurial ecosystems in domestic capital accumulation and value creation. Together, these and similar steps have the capability to shift the balance from the DME model towards a more competitive and resilient “successor model” where the interests of FDI and domestic development can be fruitfully reconciled.

Environmentally sensitive sex determination may help organisms adapt to environmental change but also makes them vulnerable to anthropogenic stressors, with diverse consequences for population dynamics and evolution. The mechanisms translating environmental stimuli to sex are controversial: although several fish experiments supported the mediator role of glucocorticoid hormones, results on some reptiles challenged it. We tested this hypothesis in amphibians by investigating the effect of corticosterone on sex determination in agile frogs (Rana dalmatina). This species is liable to environmental sex reversal whereby genetic females develop into phenotypic males. After exposing tadpoles during sex determination to waterborne corticosterone, the proportion of genetic females with testes or ovotestes increased from 11% to up to 32% at 3 out of 4 concentrations. These differences were not statistically significant except for the group treated with 10 nM corticosterone, and there was no monotonous dose‐effect relationship. These findings suggest that corticosterone is unlikely to mediate sex reversal in frogs. Unexpectedly, animals originating from urban habitats had higher sex‐reversal and corticosterone‐release rates, reduced body mass and development speed, and lower survival compared to individuals collected from woodland habitats. Thus, anthropogenic environments may affect both sex and fitness, and the underlying mechanisms may vary across ectothermic vertebrates. Research Highlights: A suspected mediator of environmentally sensitive sex determination is the glucocorticoid stress response. Our experiment on agile frogs did not support this hypothesis, but urban individuals had higher sex‐reversal and corticosterone‐release rates. [ABSTRACT FROM AUTHOR]

A tanulmány a pénzügyi szektor szemüvegén keresztül mutatja be a regionális tudomány és az új gazdaságföldrajz által azonosított „kihívásoknak” (globális/lokális dichotómia, „földrajzi távolság/közelség”, „az agglomerációk és térbeli koncentrációk) valamint az általuk formált térfolyamatoknak a relevanciáját. A tanulmány azt vizsgálja, hogy a regionális tudomány által használt térkategóriák mennyire azonosíthatók a pénzügyi tér működésében. A szerző a térgazdaságtani, az új gazdaságföldrajzi és a pénzügyi elméletek elemzésén keresztül bizonyítja, hogy a pénzügyi rendszereknek alapvető jellemzője a térbeli meghatározottság. A pénzügyi globalizációnak a technológiai fejlődés által áthatott térbeli folyamatai nem enyhítették a távoli földrajzi helyek között meglévő információs aszimmetriát, illetve nem növelték a pénzügyi rendszerek stabilitását sem. Fontos szerepe van az időzónák földrajzi differenciáinak, és továbbra is akadályozzák az integrációt olyan tényezők, mint a szabályozási és adózási környezet, az adminisztrációs terhek, a vállalati kultúra különbségei, a jelentős tranzakciós költségek és az információs aszimmetria. Cáfolható az a vélemény, amely szerint a fejlődés során a tér elveszítené szerepét, leértékelődne a távolság, és megszűnnének a pénzügyi piacokat jellemző térbeli különbségek. A globális pénzügyi központok növekvő koncentrációja is bizonyítja a térbeliség szerepét, mivel a helyhez kötött, személyes kapcsolatokon alapuló minőségi információk csak ezekben szerezhetők meg.

Analyzing hybrid zones allows insight into interactions between previously isolated lineages. The distributions of firebellied toads (Bombina bombina) and yellow-bellied toads (B. variegata) meet in the Carpathian Basin. We aimed to explore the genetic composition of a transient zone between the two sister species along a transect in the Carpathian foothill region. We collected 230 specimens from 21 locations and sampled them using buccal swabs. We used mitochondrial markers and designed a novel test based on the restriction of the nuclear Ncx-1 gene to distinguish between the two species and determine hybrid individuals. According to our results, the complete Börzsöny Hills and many locations in Krupinská Planina were colonized by B. bombina, including typical B. variegata habitats at higher elevations. However, in Krupinská Planina, the most remote sites still harbor B. variegata populations, often mixed with hybrid individuals. This pattern may indicate the northward and altitudinal range expansion of B. bombina. Our results warrant enhanced attention to hybrid zones, where introgression and other changes in the populations' genetic composition may reflect recent rapid environmental alterations. [ABSTRACT FROM AUTHOR]