Exporting and Firm Performance: Chinese Exporters and the Asian Financial Crisis

This paper analyzes firm panel data to examine how export demand shocks associated with the 1997 Asian financial crisis affected Chinese exporters. We construct firm-specific exchange rate shocks based on the pre-crisis destinations of firms’ exports. Because the shocks were unanticipated and large in magnitude, they are an ideal instrument for identifying the impact of exporting on firm productivity and other aspects of firm performance. We find that firms whose export destinations experience greater currency depreciation have slower growth in exports and that export growth increases firm productivity as well as other measures of firm performance. Consistent with the “learning-by-exporting” hypothesis, greater exports increase the productivity of firms exporting to developed countries but not of firms exporting via Hong Kong or directly to poorer destinations.

Exporting and Firm Performance: Chinese Exporters and the Asian Financial Crisis

We ask how export demand shocks associated with the Asian financial crisis affected Chinese exporters. We construct firm-specific exchange rate shocks based on the pre-crisis destinations of firms' exports. Because the shocks were unanticipated and large, they are a plausible instrument for identifying the impact of exporting on firm productivity and other outcomes. We find that firms whose export destinations experience greater currency depreciation have slower export growth, and that export growth leads to increases firm productivity and other firm performance measures. Consistent with "earning-by-exporting", the productivity impact of export growth is greater when firms export to more developed countries.

Exporting and Firm Performance: Chinese Exporters and the Asian Financial Crisis

This paper analyzes firm panel data to examine how export demand shocks associated with the 1997 Asian financial crisis affected Chinese exporters. We construct firm-specific exchange rate shocks based on the pre-crisis destinations of firms’ exports. Because the shocks were unanticipated and large in magnitude, they are an ideal instrument for identifying the impact of exporting on firm productivity and other performance measures. For the period 1995 to 1998, we estimate an elasticity of Chinese exports with respect to a foreign trading partner’s real exchange rate of -0.48. Exporting is found to significantly boost a firm’s total factor productivity, net value added per worker, total sales, and return on assets.http://deepblue.lib.umich.edu/bitstream/2027.42/21612/1/IPC-working-paper-003-parkyangshijiang_expprod.pd

Study on A Novel Sacrificial-Energy Dissipation Outrigger

The frame-core tube-outrigger structural system is widely used in tall buildings, in which outriggers coordinate the deformation between the core tube and the moment frame, leading to a larger structural lateral stiffness. Existing studies indicate that outriggers can be designed as a fuse of tall buildings through dissipating seismic energy after yielding, to protect the main structure. Under the action of the maximum considered earthquake (MCE), it is found that the hardening effect of BRB outriggers will increase the percentage of the inelastic energy dissipation of the other structural components. Meanwhile, due to the local buckling-induced severe deterioration and damage of conventional outriggers, conventional outriggers are difficult to repair after an earthquake. To overcome these problems, this study proposes a novel sacrificial-energy dissipation outrigger (SEDO) to improve the seismic resilience of tall buildings. The inclined braces of this novel SEDO are composed of a sacrificial part and an energy dissipation part. Therefore, it remains elastic under the design-based earthquake (DBE) and dissipates inelastic energy under the MCE. Moreover, the detailing of this novel SEDO are proposed based on experimental studies. The optimum strength ratio between the sacrificial part and the energy dissipation part is determined as 6:4 based on nonlinear time-history analyses (THAs). Afterwards, SEDOs are used in a tall building to verify its seismic performance through nonlinear THAs. Consequently, this study indicates that the novel SEDO is able to protect the other structural components and effectively improve the seismic resilience of tall buildings.The authors are grateful for the financial support from the National Natural Science Foundation of China (No. 51778341)

Topological Interface-State Lasing in a Polymer-Cholesteric Liquid Crystal Superlattice

The advance of topological photonics has heralded a revolution for manipulating light as well as for the development of novel photonic devices such as topological insulator lasers. Here, we demonstrate topological lasing of circular polarization in a polymer-cholesteric liquid crystal (P-CLC) superlattice, tunable in the visible wavelength regime. By use of the femtosecond-laser direct-writing and self-assembling techniques, we establish the P-CLC superlattice with a controlled mini-band structure and a topological interface defect, thereby achieving a low threshold for robust topological lasing at about 0.4 uJ. Thanks to the chiral liquid crystal, not only the emission wavelength is thermally tuned, but the circularly polarized lasing is readily achieved. Our results bring about the possibility to realize compact and integrated topological photonic devices at low cost, as well as to engineer an ideal platform for exploring topological physics that involves light-matter interaction in soft-matter environments.Comment: 14 pages, 4 figure

The deterioration of starch physiochemical and minerals in high-quality indica rice under low-temperature stress during grain filling

Low temperatures during the grain-filling phase have a detrimental effect on both the yield and quality of rice grains. However, the specific repercussions of low temperatures during this critical growth stage on grain quality and mineral nutrient composition in high-quality hybrid indica rice varieties have remained largely unexplored. The present study address this knowledge gap by subjecting eight high-quality indica rice varieties to two distinct temperature regimes: low temperature (19°C/15°C, day/night) and control temperature (28°C/22°C) during their grain-filling phase, and a comprehensive analysis of various quality traits, with a particular focus on mineral nutrients and their interrelationships were explored. Exposure of rice plants to low temperatures during early grain filling significantly impacts the physicochemical and nutritional properties. Specifically, low temperature increases the chalkiness rate and chalkiness degree, while decreases starch and amylopectin content, with varying effects on amylose, protein, and gelatinization temperature among rice varieties. Furthermore, crucial parameters like gelatinization enthalpy (ΔH), gelatinization temperature range (R), and peak height index (PHI) all significantly declined in response to low temperature. These detrimental effects extend to rice flour pasting properties, resulting in reduced breakdown, peak, trough, and final viscosities, along with increased setback. Notably, low temperature also had a significant impact on the mineral nutrient contents of brown rice, although the extent of this impact varied among different elements and rice varieties. A positive correlation is observed between brown rice mineral nutrient content and factors such as chalkiness, gelatinization temperature, peak viscosity, and breakdown, while a negative correlation is established with amylose content and setback. Moreover, positive correlations emerge among the mineral nutrient contents themselves, and these relationships are further accentuated in the context of low-temperature conditions. Therefore, enhancing mineral nutrient content and increasing rice plant resistance to chilling stress should be the focus of breeding efforts to improve rice quality

Mechanism and Growth of Flexible ZnO Nanostructure Arrays in a Facile Controlled Way

Nanostructure arrays-based flexible devices have revolutionary impacts on the application of traditional semiconductor devices. Here, a one-step method to synthesize flexible ZnO nanostructure arrays on Zn-plated flexible substrate in Zn(NO3)2/NH3⋅H2O solution system at 70–90∘C was developed. We found out that the decomposition of Zn(OH)2 precipitations, formed in lower NH3⋅H2O concentration, in the bulk solution facilitates the formation of flower-like structure. In higher temperature, 90∘C, ZnO nanoplate arrays were synthesized by the hydrolysis of zinc hydroxide. Highly dense ZnO nanoparticale layer formed by the reaction of NH3⋅H2O with Zn plating layer in the initial self-seed process could improve the vertical alignment of the nanowires arrays. The diameter of ZnO nanowire arrays, from 200 nm to 60 nm, could be effectively controlled by changing the stability of Zn(NH3)42+ complex ions by varying the ratio of Zn(NO3)2 to NH3⋅H2O which further influence the release rate of Zn2+ ions. This is also conformed by different amounts of the Zn vacancy as determined by different UV emissions of the PL spectra in the range of 380–403 nm

Long-term effects of different hypoglycemic drugs on carotid intima-media thickness progression: a systematic review and network meta-analysis

ObjectiveThe progression of carotid intima-media thickness (cIMT) can partially predict the occurrence of future cardiovascular events. This network meta-analysis compared the effects of 14 antidiabetic drugs (acarbose, alogliptin, exenatide, glibenclamide, glimepiride, ipragliflozin, metformin, nateglinide, pioglitazone, rosiglitazone, sitagliptin, tofoglifozin, troglitazone, voglibose) on the progression of cIMT.MethodPubMed, EMBASE, Cochrane Library, and Web of Science were searched to screen all clinical trials of treatment of cIMT with hypoglycemic agents before March 1, 2024. The differences in the changes in cIMT between the treatment group and control group were evaluated.ResultAfter screening 8395 citations, 25 studies (6675 patients) were included. The results indicated that exenatide had the best efficacy in slowing down cIMT progress, and exenatide [MD=-0.13,95%CI (-0.25, -0.01)], alogliptin [MD=-0.08,95%CI (-0.13, -0.02)] and metformin [MD=-0.05, 95%CI (-0.09, -0.02)] are more effective than placebo.ConclusionLong-term treatment of exenatide, alogliptin, and metformin may be more effective than other hypoglycemic drugs in slowing the progression of cIMT.Systematic Review Registrationhttps://www.crd.york.ac.uk/PROSPERO/, identifier CRD42024519474

Efficacy of physical exercise on the physical ability, cardiac function and cardiopulmonary fitness of patients with atrial fibrillation: a systematic review and meta-analysis

ObjectiveIt is advised that patients engage in physical activity to enhance their quality of life and achieve better results. The purpose of the current study was to measure the efficacy of exercise on the physical ability, cardiac function and cardiopulmonary fitness of patients with AF.MethodA comprehensive systematic literature search was performed in PubMed, Embase, and Web of Science from 1991 to 2023 for RCTs comparing physical exercise combined with AF routine treatments to routine treatments alone. The meta-analysis was conducted following PRISMA guidelines. Our main outcomes were physical ability (measured by the 6-min walk test, 6MWT), cardiac function (measured by left ventricular ejection fraction, LVEF) and cardiopulmonary fitness (measured by peak oxygen uptake and resting heart rate). Quality assessments were conducted using the Cochrane Collaboration tool.ResultsThirteen trials involving 672 patients met the criteria for analysis. The results showed that physical exercise increased physical ability by improving the 6MWT (m) performance (MD = 96.99, 95% CI: 25.55–168.43; Z = 2.66; p = 0.008); and enhanced peak VO2 (ml/kg per min) (MD = 4.85, 95% CI: 1.55–8.14; Z = 2.89; p = 0.004) while reducing resting heart rate (beats per minute, bpm) (MD = −6.14, 95% CI: −11.30 to −0.98; Z = 2.33; p = 0.02). However, the results showed that regular exercise could improve LVEF (%) inpatients clinically, which had no statistic difference between experimental and control group (MD = 1.49, 95% CI: −0.25–3.24; Z = 1.68; p = 0.09).ConclusionOur meta-analysis shows that physical exercise is an effective intervention to improve the exercise ability and cardiopulmonary fitness for AF patients. Meanwhile, we also do not exclude the positive effect of exercise on the improvement of cardiac function (LVEF) in patients with AF. To this end, doctors should consider the positive impact of exercise on patients and give advice on exercise limits in practical clinical practice