40 research outputs found
The Harrod-Balassa-Samuelson Hypothesis: Real Exchange Rates and their Long-Run Equilibrium
Frictionless, perfectly competitive traded-goods markets justify thinking of purchasing power parity (PPP) as the main driver of exchange rates in the long-run. But differences in the traded/non-traded sectors of economies tend to be persistent and affect movements in local price levels in ways that upset the PPP balance (the underpinning of the Harrod-Balassa-Samuelson hypothesis, HBS). This paper uses panel-data techniques on a broad collection of countries to investigate the long-run properties of the PPP/HBS equilibrium using novel local projection methods for cointegrated systems. These semi-parametric methods isolate the long-run behavior of the data from contaminating factors such as frictions not explicitly modelled and thought to have effects only in the short-run. Absent the short-run effects, we find that the estimated speed of reversion to long-run equilibrium is much higher. In addition, the HBS effects means that the real exchange rate is converging not to a steady mean, but to a slowly to a moving target. The common failure to properly model this effect also biases the estimated speed of reversion downwards. Thus, the so-called "PPP puzzle" is not as bad as we thought.
Abnormal phosphorylation of Tie2/Akt/eNOS signaling pathway and decreased number or function of circulating endothelial progenitor cells in prehypertensive premenopausal women with diabetes mellitus
CRISPR/Cas genome editing in grapevine: recent advances, challenges and future prospects
The development of clustered regularly interspaced short palindromic repeats/CRISPR associated protein 9 (CRISPR/Cas9) system has revolutionized genome editing and plant breeding. Applications of CRISPR/Cas9 technology in fruit crops, including grapevine, enable precise improvement of agronomically important traits. In this review, we first describe genome editing based on the most widely used CRISPR/Cas9 system and recently developed CRISPR technologies. We then focus on applications of CRISPR/Cas9 in improvement of disease resistance, optimization of CRISPR/Cas9 systems, multiplex genome editing and off-target effect analysis in grapevine. We also discuss the challenges facing genome editing that should be overcome to realize the potential of CRISPR technology in grapevine. Finally, we highlight possible future experimental considerations for more precise and efficient genome editing in grapevine
Hybrid perceptual training to facilitate the learning of nasal final contrasts by highly proficient Japanese learners of Mandarin
Native speakers of Japanese experience challenges in differentiating Mandarin nasal finals, even after years of experience with Mandarin. We used a hybrid perceptual training approach with highly proficient Japanese learners of Mandarin to improve their ability to distinguish nasal final contrasts, which are not distinctive in Japanese. Eight learners participated in a 6-day adaptive and high-variability perceptual training procedure, including a pre-, mid-, and posttest on categorisation of nasal finals, whereas eight control participants received the same three tests without the intervening training. No significant prepost performance changes were observed in the controls, whereas the trainees achieved an overall 13% improvement in identifying nasal final contrasts and better categorisation of nasal final continua. Additionally, they showed better generalisation to untrained nasal finals in both citation form and continuous speech. These findings suggest that hybrid adaptive and high-variability perceptual training helps facilitate highly proficient foreign learners' formation of non-native phonological representations
Flexible Cathode Enabled by Ultralong Na<sub>2</sub>V<sub>6</sub>O<sub>16</sub>·3H<sub>2</sub>O Nanowire for High Rate and Durable Aqueous Zinc Ion Batteries
Aqueous zinc ion batteries (ZIBs) have garnered increasing
attention
owing to their safe aqueous electrolyte and suitable energy and power
density. However, the development of appropriate cathode materials
for commercialization remains a challenge. Herein, we report a flexible
binder-free film cathode composed of hydrated sodium vanadate nanowires
and carbon nanotubes (NaVO/CNT). The as-prepared film cathode exhibits
a remarkably high rate performance, delivering a capacity of 402 mAh
g–1 at 0.1 A g–1 and 284 mAh g–1 at 6 A g–1. Furthermore, excellent
long-term stability is achieved with a retention rate of 90.04% after
5000 cycles at 4 A g–1. This cathode demonstrates
outstanding performance compared with those of other sodium vanadate-based
cathodes in aqueous ZIBs. Additionally, the co(de)insertion mechanism
of H+ and Zn2+ ions is verified
Perspectives on removal of atmospheric methane
Methane's contribution to radiative forcing is second only to that of CO2. Though previously neglected, methane is now gaining increasing public attention as a GHG. At the recent COP26 in Glasgow, 105 countries signed “the methane pledge” committing to a 30% reduction in emissions from oil and gas by 2030 compared to 2020 levels. Removal methods are complementary to such reduction, as they can deal with other sources of anthropogenic emissions as well as legacy emissions already accumulated in the troposphere. They can also provide future insurance in case biogenic emissions start rising significantly. This article reviews proposed methods for atmospheric methane removal at a climatically significant scale. These methods include enhancement of natural hydroxyl and chlorine sinks, photocatalysis in solar updraft towers, zeolite catalyst in direct air capture devices, and methanotrophic bacteria. Though these are still at an early stage of development, a comparison is provided with some carbon dioxide removal methods in terms of expected costs. The cheapest method is potentially enhancement of the chlorine natural sink, costing as little as $1.6 per ton CO2-eq, but this should be carried out over remote areas to avoid endangering human health. Complementarity with methane emissions reduction is also discussed