To see the other types of publications on this topic, follow the link: Exchange rate limit.
Journal articles on the topic 'Exchange rate limit'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Exchange rate limit.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Dransfeld, P., J. Lukacs-Paal, and H. Gg Wagner. "Direct Measurements of the Isotope Exchange Reactions between 18OH and NO, NO2, N2O and O2." Zeitschrift für Naturforschung A 41, no. 11 (November 1, 1986): 1283–88. http://dx.doi.org/10.1515/zna-1986-1103.
Full textAbstract:
The isotope exchange reactions between 18OH and NO, NO2, N2O and O2 were studied at room temperature in a discharge flow system with laser magnetic resonance detection of 18OH and 16OH. Exchange rate constants of where obtained for NO and NO2, respectively. Upper limits of k < 1 · 108 cm3/mol s can be reported for the reactionsThe results are compared with recombination rate data in the limit of high pressures and with vibrational deactivation measurements.
2
Melvin, Michael, Lukas Menkhoff, and Maik Schmeling. "Exchange rate management in emerging markets: Intervention via an electronic limit order book." Journal of International Economics 79, no. 1 (September 2009): 54–63. http://dx.doi.org/10.1016/j.jinteco.2009.06.008.
Full text
3
Franco, Tertuliano, Adriana Neumann, and Glauco Valle. "Hydrodynamic Limit for a Type of Exclusion Process with Slow Bonds in Dimension d ≥ 2." Journal of Applied Probability 48, no. 02 (June 2011): 333–51. http://dx.doi.org/10.1017/s0021900200007919.
Full textAbstract:
Let Λ be a connected closed region with smooth boundary contained in the d-dimensional continuous torus T d . In the discrete torus N -1 T d N , we consider a nearest-neighbor symmetric exclusion process where occupancies of neighboring sites are exchanged at rates depending on Λ in the following way: if both sites are in Λ or Λc, the exchange rate is 1; if one site is in Λ and the other site is in Λc, and the direction of the bond connecting the sites is e j , then the exchange rate is defined as N -1 times the absolute value of the inner product between e j and the normal exterior vector to ∂Λ. We show that this exclusion-type process has a nontrivial hydrodynamical behavior under diffusive scaling and, in the continuum limit, particles are not blocked or reflected by ∂Λ. Thus, the model represents a system of particles under hard-core interaction in the presence of a permeable membrane which slows down the passage of particles between two complementary regions.
4
Franco, Tertuliano, Adriana Neumann, and Glauco Valle. "Hydrodynamic Limit for a Type of Exclusion Process with Slow Bonds in Dimension d ≥ 2." Journal of Applied Probability 48, no. 2 (June 2011): 333–51. http://dx.doi.org/10.1239/jap/1308662631.
Full textAbstract:
Let Λ be a connected closed region with smooth boundary contained in the d-dimensional continuous torus Td. In the discrete torus N-1TdN, we consider a nearest-neighbor symmetric exclusion process where occupancies of neighboring sites are exchanged at rates depending on Λ in the following way: if both sites are in Λ or Λc, the exchange rate is 1; if one site is in Λ and the other site is in Λc, and the direction of the bond connecting the sites is ej, then the exchange rate is defined as N-1 times the absolute value of the inner product between ej and the normal exterior vector to ∂Λ. We show that this exclusion-type process has a nontrivial hydrodynamical behavior under diffusive scaling and, in the continuum limit, particles are not blocked or reflected by ∂Λ. Thus, the model represents a system of particles under hard-core interaction in the presence of a permeable membrane which slows down the passage of particles between two complementary regions.
5
Cavusoglu, Nevin. "Exchange Rates and the Effectiveness of Actual and Oral Official Interventions: A Survey on Findings, Issues and Policy Implications." Global Economy Journal 10, no. 4 (December 2010): 1850213. http://dx.doi.org/10.2202/1524-5861.1694.
Full textAbstract:
Monetary authorities of many open economies have been regularly intervening in foreign exchange markets for years to limit volatility in exchange rates and/or push exchange rates back to some desired level. Such interventions have taken the form of actual and oral official interventions. Review of studies investigating the effectiveness of interventions reveals one major issue, related to the assumption that interventions are mostly sterilized. This assumption might lead to unreliable results when changes in interest rates and interventions are both used as explanatory variables for exchange rates. One major consistent finding is that intervention has a significant but short-lasting effect on exchange rates. Studies have reached this conclusion by investigating whether intervention has been effective in turning around the exchange rate over the few days, weeks or months following intervention(s). Only a few studies have investigated and provided evidence that intervention has been effective in limiting long swings in exchange rates. Studies testing for the effectiveness of interventions specifically through the signaling channel also provide evidence on the importance of macroeconomic variables for exchange rates. The significance of official intervention and official communication for exchange rate movements combined with the importance of macroeconomic variables for exchange rates provide a role for official intervention and parity announcement to influence exchange rate movements and limit the magnitude of exchange rate swings.
6
TARAWALIE, Abu Bakarr. "Equilibrium Real Exchange Rate and Misalignment: The Sierra Leone Perspective." Applied Economics and Finance 8, no. 3 (June 21, 2021): 41. http://dx.doi.org/10.11114/aef.v8i3.5267.
Full textAbstract:
This paper estimates the equilibrium real effective exchange rate and determine the level of exchange rate misalignment in Sierra Leone, for the period 1980 to 2018. The paper utilizes the behavioral equilibrium exchange rate methodology within the Johansen maximum likelihood framework to estimate the long run equilibrium real effective exchange rate. The unit root test result shows that all the variables are integrated of order one, whilst the cointegration test establishes the existence of one cointegrating vector as evidenced by both the Trace and Maximum Eigen Statistics. The normalized long run results reveal that openness, government expenditure and money supply were the most significant determinants of the real effective exchange rate in the long run. Furthermore, the findings reveal that the real effective exchange rate experienced sustained deviation from the long run equilibrium real effective exchange rate during the study period, with episodes of overvaluation and undervaluation. Specifically, the real effective exchange rate was overvalued by 3.69 percent during the period between 1980-1985; undervalued by 1.8 percent between 1986-1997, and overvalued by 0.9 percent between 1998-2004, Thus, the paper reveals episodes of misalignment of the real effective exchange rate. Based on these findings, the study recommends that, the monetary authorities should ensure stability of the exchange rate and maintain price stability, through sterilization of capital flows as well as contain money growth within the statutory limit.
7
Kim, Dowan. "Institutional Constraints on the Rate of Derivatives in Leveraged Exchange-Traded Fund." Korean Journal of Financial Studies 49, no. 2 (April 30, 2020): 217–48. http://dx.doi.org/10.26845/kjfs.2020.04.49.2.217.
Full textAbstract:
This study confirmed whether the rate of derivatives in leveraged exchange-traded funds (ETF) calculated by derivatives and net asset value (NAV) affect their tracking errors. This research established three findings. First, when the rate of derivatives was limited at 100%, the tracking error of the leveraged ETF targeted on 2 times of the index was affected by the rate of derivatives. Second, when the rate of derivatives was eased to 200%, the same-day tracking error of the leveraged ETF targeted on 2 times of the futures index that launched after the constraints was affected by the rate of derivatives. Third, this study analyzed the constraints of the rate of derivatives after determining whether the leveraged ETF targeted on 2 times of the index indicates whether the rate of derivatives is close to 200%. As a result, even when the rate of derivatives is slightly over the 200% limit, the tracking error was lower. Even when the constraints were slightly over the limit, the tracking error was shown to be significantly lower than the other data set. This result implies that when there is an institutional constraint on the rate of derivatives, there can be limitations to fund management of leveraged ETF targeted on 2 times of the futures index.
8
Khan, Muhammad Asif, Ghulam Mujtaba Chaudhary, and Khalid Latif. "How Consumer Confidence, Corruption and Credit Rating Effect the Exchange Rate: Emerging Market Perspective." Journal of Accounting and Finance in Emerging Economies 6, no. 2 (June 13, 2020): 367–79. http://dx.doi.org/10.26710/jafee.v6i2.1109.
Full textAbstract:
The paper empirically examines whether the international rating influences the rate of exchange of an economy in the long run? The paper employs Autoregressive Distributed Lag (ARDL) Bounds testing methodology on the exchange rate of China and contemporary international rating, using time series data from 1996Q1 to 2016Q4. The empirical analysis confirms the presence of a cointegration relationship between country rating and the exchange rate. To be more specific; corruption index, credit rating, and inflation are significantly and negatively cointegrated with the exchange rate of China. Conversely, consumer confidence is uncorrelated with the exchange rate over the long run. The paper focuses only on the exchange rate of CNY-USD; this may limit the generalizability of results for exchange rate with other nations. Nevertheless, the results add to the exchange rate determinants literature by including country-rating indicators in the analysis. Prior literature documents that there is some relationship between inflation and exchange rate. This research is novel in the application of robust ARDL and bounds testing to examine the long and short-run association of country rating of China with its exchange rate, after controlling for inflation.
9
Hofmann, A. F., E. T. Peltzer, and P. G. Brewer. "Kinetic bottlenecks to respiratory exchange rates in the deep-sea – Part 1: Oxygen." Biogeosciences 10, no. 7 (July 25, 2013): 5049–60. http://dx.doi.org/10.5194/bg-10-5049-2013.
Full textAbstract:
Abstract. Ocean warming is now reducing dissolved oxygen concentrations, which can pose challenges to marine life. Oxygen limits are traditionally reported simply as a static concentration threshold with no temperature, pressure or flow rate dependency. Here we treat the oceanic oxygen supply potential for heterotrophic consumption as a dynamic molecular exchange problem analogous to familiar gas exchange processes at the sea surface. A combination of the purely physico-chemical oceanic properties temperature, hydrostatic pressure, and oxygen concentration defines the ability of the ocean to provide the oxygen supply to the external surface of a respiratory membrane. This general oceanic oxygen supply potential is modulated by further properties such as the diffusive boundary layer thickness to define an upper limit to oxygen supply rates. While the true maximal oxygen uptake rate of any organism is limited by gas transport either across the respiratory interface of the organism itself or across the diffusive boundary layer around an organism, controlled by physico-chemical oceanic properties, it can never be larger than the latter. Here, we define and calculate quantities that describe this upper limit to oxygen uptake posed by physico-chemical properties around an organism and show examples of their oceanic profiles.
10
Proskurnina, Nadiia, Jürgen Kähler, and Rosario Cervantes-Martinez. "The impact of real exchange rates on price competitiveness in Eastern European countries." Economics of Development 19, no. 1 (June 5, 2020): 45–55. http://dx.doi.org/10.21511/ed.19(1).2020.05.
Full textAbstract:
The subject of this paper is empirical research on studies of exchange rates in Eastern European countries, such as Albania, Bulgaria, Bosnia and Herzegovina, Belarus, Czech Republic, Estonia, Croatia, Hungary, Latvia, Lithuania, Moldova, (North) Macedonia, Montenegro, Poland, Romania, Serbia, Slovakia, and Slovenia, in order verify the validity of theories that explain these changes. This research aims to explain the mixed evidence of the Balassa-Samuelson effect in Ukraine, taking into account the intentions of Ukraine to become a member of the European Union. Unlike previous works, the attention is shifted to a review of empirical evidence and the identification of main factors that limit the ability to verify the theory. The main conclusion is that all the currencies studied underwent substantial real appreciations during the study period. Thus, it can be concluded that an adequate monetary policy in countries under study is very important, given that local exchange markets are not sustainable enough and the volatility of exchange operations is higher than in countries with developed economies. However, the Balassa-Samuelson Hypothesis (BSH) can explain the impact of the real exchange rate due to changes in productivity in countries in transition.
11
Werstiuk, Nick Henry, and Sujit Banerjee. "Towards a complete account of diastereotopic hydrogen isotope exchange of carbon acids. III. Base-catalyzed exchange of sulfoxides. Evidence for exchange by inversion." Canadian Journal of Chemistry 63, no. 8 (August 1, 1985): 2100–2109. http://dx.doi.org/10.1139/v85-346.
Full textAbstract:
The rate constants for deuteroxide and hydroxide catalyzed H → D and D → H exchange of benzodihydrothiophene oxide (1a) and several of its deuterated analogs 1b, 1c, and 1d at 30.00 ± 0.05 °C are reported along with the rate constants for D → H exchange of deuterated benzyl methyl sulfoxides 2b and 2c. Application of the steady-state assumption to schemes involving equilibrating pyramidal anions yield equations which are used to fit experimentally determined (kf/ks)H → D and (kf/ks)D → H ratios. The analysis supports our view that exchange of the diastereotopic protons (deuterons) occurs by inversion. The inversion component contributes significantly to exchange of the "slow" proton (deuteron) of a diastereotopic pair and this accounts for the observation that (kf/ks)D → H < (kf/ks)H → D. This study establishes an upper limit of 6 kcal for the barrier to inversion of the carbanions derivable from 1 and 2, if pyramidal anions are formed.
12
Anderson, S. M., J. Morton, and K. Mauersberger. "Upper limit on the rate constant for isotope exchange between molecular oxygen and ozone at 298K." Geophysical Research Letters 14, no. 12 (December 1987): 1258–61. http://dx.doi.org/10.1029/gl014i012p01258.
Full text
13
Nikinmaa, Mikko, and Bruce L. Tufts. "Regulation of acid and ion transfer across the membrane of nucleated erythrocytes." Canadian Journal of Zoology 67, no. 12 (December 1, 1989): 3039–45. http://dx.doi.org/10.1139/z89-427.
Full textAbstract:
The major pathways for proton transport across the membrane of nucleated erythrocytes are the passive Jacobs–Stewart cycle and the secondarily active sodium–proton exchange. The relative importance of these two pathways in the control of red cell pH depends on the sodium–proton exchange rate and the rate of the slowest step of passive proton equilibration. In cyclostome red cells, which lack anion exchange, intracellular pH is controlled by the sodium-dependent acid–extrusion mechanism. In unstimulated teleost red cells, the Jacobs–Stewart cycle appears to be the most important pathway for the transport of protons across the membrane. Adrenergic stimulation activates sodium–proton exchange. Sodium–proton exchange is able to increase intracellular pH and decrease extracellular pH because the rate of proton transport via the Jacobs–Stewart cycle is limited by the uncatalysed extracellular dehydration of carbonic acid to carbon dioxide. The turnover rate of the adrenergically activated sodium–proton exchange is influenced by pH and oxygen tension. In amphibian red cells, acidification activates sodium–proton exchange. The exchange may limit the changes in intracellular pH after acid–base disturbances.
14
Hu, Bo, Zi Chao Wang, Meng Chun Gao, Zong Lian She, and Cong Cong Zhao. "Effect of Aeration Rate on Forced-Aeration Composting of Sewage Sludge and Maize Straw." Applied Mechanics and Materials 178-181 (May 2012): 843–46. http://dx.doi.org/10.4028/www.scientific.net/amm.178-181.843.
Full textAbstract:
The composting of sewage sludge and maize straw was investigated in forced-aeration composting systems at aeration rates of 0.28, 0.56 and 0.83 l min-1kg-1organic matter, corresponding to pile A, pile B and pile C. The composting temperature in three piles met the hygienic safety criterion, and final electrical conductivity did not exceed the limit value of 3000 μS cm-1. The final NH4+-N content in pile C exceeded the limit value of 400 mg kg-1. The final NO3--N content, cation exchange capacity and germination index in pile B were superior to those in pile A and pile C.
15
Rotheli, Tobias F. "Appreciation Pressures and Real Depreciation: The Experience with the Swiss Franc-Euro Exchange Rate Floor." International Business Research 9, no. 8 (June 23, 2016): 84. http://dx.doi.org/10.5539/ibr.v9n8p84.
Full textAbstract:
<p>We study the course of the Swiss price level during the recent episode where Switzerland enforced a floor on the Swiss Franc exchange rate relative to the Euro. Given the strong nominal upward pressure on the Swiss currency the introduced limit of 1.20 Francs per Euro led to a quasi-fixed exchange rate from 2011 until early 2015. This measure was specifically aimed at helping the firms of the Swiss export sector to compete internationally. A further reason for imposing this floor was the Swiss National Bank’s concern with deflationary pressures. Interestingly, it turned out that during the episode with a quasi-fixed exchange rate the Swiss price level came under downward pressure. We offer an analysis that helps to understand this depreciation of the Swiss currency in real terms which in fact contributed to the exchange rate floor being eventually abandoned. The article thus clarifies some intricate mechanisms affecting the choice of exchange rate policies which are so important for firms in the export sector. As a theoretical contribution (complementing the well-known Balassa-Samuelson analysis) the article presents a computable equilibrium model that explains real exchange rate variations with diverging trends in the productivity growth of the non-traded goods sectors of economies.</p>
16
Chaudhry, Ali Farhan, Mian Muhammd Hanif, Sameera Hassan, and Muhammad Irfan Chani. "Efficiency of the Black Foreign Exchange Market." International Journal of Economics and Finance 11, no. 2 (January 20, 2019): 165. http://dx.doi.org/10.5539/ijef.v11n2p165.
Full textAbstract:
This empirical study is first of its nature to examine the weak-form of efficiency for unofficial foreign exchange market of Pakistan proxied by Japanese Yen (JPY/PKR), Swiss Franc (CHF/PKR), British Pound (GBP/PKR), and US Dollar (USD/PKR) exchange rates. For this we have employed Ljung Box Q-test, unit root tests including Dickey-Fuller (Dickey 1979), Augmented Dickey-Fuller (Dickey 1981) tests and Phillips and Perron (1988) test, Durbin Watson test, Runs-test, and Variance ratio test by using unofficial foreign exchange rate time series of Yen/PKR, CHF/PKR, GBP/PKR and USD/PKR from 1994M07 to 2001M06. Empirical results lead to the conclusion that the unofficial foreign exchange market of Pakistan is weak-form efficiency. The implications of this empirical research are of great importance for designing foreign exchange policy i.e. policy makers (be it accounting, export/import or public policy makers) are to consider fluctuations in unofficial foreign exchange rates while designing official foreign exchange rate policy of developing country like Pakistan. Further, policymakers can enhance the efficiency of official foreign exchange market by intervention subject to a widening of unofficial foreign exchange premium beyond a certain limit in developing countries like Pakistan.
17
Alonso-Carrera, Jaime, and Timothy Kam. "ANATOMIZING INCOMPLETE-MARKETS SMALL OPEN ECONOMIES: POLICY TRADE-OFFS AND EQUILIBRIUM DETERMINACY." Macroeconomic Dynamics 20, no. 4 (May 5, 2015): 1022–50. http://dx.doi.org/10.1017/s1365100514000728.
Full textAbstract:
We propose a simple incomplete-markets small-open-economy model that is amenable to analytical dissection of its policy-relevant mechanisms. In contrast to its complete-markets limit, the equilibrium real exchange rate is irreducible from the incomplete-markets equilibrium. Market incompleteness exacerbates the domestic-inflation and output-gap monetary-policy trade-off in two ways: its steepness and its resulting endogenous cost-push to the trade-off. The latter depends on an equilibrium combination of structural shocks and on agents' beliefs of future events. Thus, in comparison to its complete-markets and closed-economy limits, standard Taylor-type rules are less capable of inducing determinate rational expectations equilibrium in our environment. Despite the larger policy trade-off under incomplete markets, simple policies that also respond to exchange-rate growth are able to manage expectations that drive the endogenous cost-push term. However, policies that respond directly to expectations may turn out to exacerbate the cost-push trade-off further, and thus, to be more likely to fuel self-fulfilling multiple or unstable equilibria.
18
Sadler, Charlotte, Kaighley Brett, Aaron Heerboth, Austin R. Swisher, Nader Mehregani, Ross Touriel, and Daniel T. Cannon. "Safety proposals for freediving time limits should consider the metabolic-rate dependence of oxygen stores depletion." Diving and Hyperbaric Medicine Journal 50, no. 4 (December 20, 2020): 356–62. http://dx.doi.org/10.28920/dhm50.4.356-362.
Full textAbstract:
(Sadler C, Brett K, Heerboth A, Swisher AR, Mehregani N, Touriel R, Cannon DT. Safety proposals for freediving time limits should consider the metabolic-rate dependence of oxygen stores depletion. Diving and Hyperbaric Medicine. 2020 December 20;50(4):356–362. doi: 10.28920/dhm50.4.356-362. PMID: 33325016.) Introduction: There is no required training for breath-hold diving, making dissemination of safety protocols difficult. A recommended breath-hold dive time limit of 60 s was proposed for amateur divers. However, this does not consider the metabolic-rate dependence of oxygen stores depletion. We aimed to measure the effect of apnoea time and metabolic rate on arterial and tissue oxygenation. Methods: Fifty healthy participants (23 (SD 3) y, 22 women) completed four periods of apnoea for 60 s (or to tolerable limit) during rest and cycle ergometry at 20, 40, and 60 W. Apnoea was initiated after hyperventilation to achieve PETCO2 of approximately 25 mmHg. Pulse oximetry, frontal lobe oxygenation, and pulmonary gas exchange were measured throughout. We defined hypoxia as SpO2 < 88%. Results: Static and exercise (20, 40, 60 W) breath-hold break times were 57 (SD 7), 50 (11), 48 (11), and 46 (11) s (F [2.432, 119.2] = 32.0, P < 0.01). The rise in PETCO2 from initiation to breaking of apnoea was dependent on metabolic rate (time × metabolic rate interaction; F [3,147] = 38.6, P < 0.0001). The same was true for the fall in SpO2 (F [3,147] = 2.9, P = 0.03). SpO2 fell to < 88% on 14 occasions in eight participants, all of whom were asymptomatic. Conclusions: Independent of the added complexities of a fall in ambient pressure on ascent, the effect of apnoea time on hypoxia depends on the metabolic rate and is highly variable among individuals. Therefore, we contend that a universally recommended time limit for breath-hold diving or swimming is not useful to guarantee safety.
19
Cui, Jin, Wei Jiang Zhang, and Feng Hai Miao. "Dynamic Simulation of the Boron Isotopes Separation by Chemical Exchange Method." Advanced Materials Research 442 (January 2012): 62–66. http://dx.doi.org/10.4028/www.scientific.net/amr.442.62.
Full textAbstract:
Abstract The enrichment ratio of 10B in the top and bottom component with the dynamic change of feed fluctuation and periodic wave on the separation process of the boron isotopes separation by chemical exchange method had been studied and a dynamic model was set up. The results indicate that when the feed amount is in the column load limit, the dynamic responses of top and bottom separation plate match well with the condition when feed flow rate is invariable. While when the exchange column is overloaded, the feed flow rate variation influences 10B abundance ratio greatly. With the increasing of the fluctuation period, the longer the wave period, the bigger the amplitude around the average line in top product. However, big increase of feed fluctuation will reduce the 10B abundance ratio of bottom product.
20
Bosupeng, Mpho, Janet Dzator, and Andrew Nadolny. "Exchange Rate Misalignment and Capital Flight from Botswana: A Cointegration Approach with Risk Thresholds." Journal of Risk and Financial Management 12, no. 2 (June 17, 2019): 101. http://dx.doi.org/10.3390/jrfm12020101.
Full textAbstract:
This study investigates the impact of exchange rate misalignment on outward capital flight in Botswana over the period 1980–2015. The study uses the autoregressive distributed lag (ARDL) approach to cointegration and the Toda and Yamamoto (1995) approach to Granger causality. Botswana’s currency misalignment was caused by current account imbalances. The most important determinant of capital flight from Botswana is trade openness, which indicates that exportable commodities are misinvoiced leading to net capital outflows. Our main findings show that in the long-run, when the currency is overvalued, the volume of capital flight through trade misinvoicing declines and increasing foreign reserves does not reduce outward capital flight. However, when the currency is undervalued, the volume of capital flight through trade misinvoicing increases and foreign reserves reduce outward capital flight. Investors respond more to prospects of devaluation than to inflation. Botswana should tolerate overvaluation of the pula of only up to 5%. When the pula is overvalued beyond 5%, capital flight increases substantially. The government has to formulate trade regulations and monitor imported and exported commodities. Botswana should also implement capital controls to limit capital smuggling and maintain monetary autonomy.
21
Yu, Wookyung, Michael C. Baxa, Isabelle Gagnon, Karl F. Freed, and Tobin R. Sosnick. "Cooperative folding near the downhill limit determined with amino acid resolution by hydrogen exchange." Proceedings of the National Academy of Sciences 113, no. 17 (April 13, 2016): 4747–52. http://dx.doi.org/10.1073/pnas.1522500113.
Full textAbstract:
The relationship between folding cooperativity and downhill, or barrier-free, folding of proteins under highly stabilizing conditions remains an unresolved topic, especially for proteins such as λ-repressor that fold on the microsecond timescale. Under aqueous conditions where downhill folding is most likely to occur, we measure the stability of multiple H bonds, using hydrogen exchange (HX) in a λYA variant that is suggested to be an incipient downhill folder having an extrapolated folding rate constant of 2 × 105 s−1 and a stability of 7.4 kcal·mol−1 at 298 K. At least one H bond on each of the three largest helices (α1, α3, and α4) breaks during a common unfolding event that reflects global denaturation. The use of HX enables us to both examine folding under highly stabilizing, native-like conditions and probe the pretransition state region for stable species without the need to initiate the folding reaction. The equivalence of the stability determined at zero and high denaturant indicates that any residual denatured state structure minimally affects the stability even under native conditions. Using our ψ analysis method along with mutational ϕ analysis, we find that the three aforementioned helices are all present in the folding transition state. Hence, the free energy surface has a sufficiently high barrier separating the denatured and native states that folding appears cooperative even under extremely stable and fast folding conditions.
22
Bhattacharya, Sharad Nath, Mousumi Bhattacharya, and Basav Roychoudhury. "Behaviour of the Foreign Exchange Rates of BRICS: Is it Chaotic?" Journal of Prediction Markets 11, no. 2 (January 19, 2018): 1–19. http://dx.doi.org/10.5750/jpm.v11i2.1247.
Full textAbstract:
The article focuses on the behaviour of foreign exchange rates of BRICS countries in reference to US dollar with special emphasis on examining presence of nonlinear dependence and deterministic chaos. The findings did not indicate random walk behaviour in the returns for all exchange rates and performance of GARCH as well as EGARCH models are reasonably good in capturing the conditional volatility. Further evidences suggest existence of nonlinear dependence and we compute Maximal Lyapunov Exponent and Correlation Dimension test with multiple surrogate series which confirms the chaotic nature of the exchange rates for all countries under study except for South Africa. The findings support short run predictability in exchange rates while long run predictions are unlikely to be successful. The chaotic nature of the foreign exchange market calls for newer intervention mechanism by the Central Bank of the respective countries to limit the exchange rate volatility.
23
Çeviş, Ismaіl, and Cem Kadilar. "The Analysis of the Short-term Capital Movements by Using the VAR Model: The Case of Turkey." Pakistan Development Review 40, no. 3 (September 1, 2001): 187–201. http://dx.doi.org/10.30541/v40i3pp.187-201.
Full textAbstract:
This paper investigates the relations among short-term capital inflows, government deficit, interest rate differentials, real exchange rate and some accounts of the balance of payments in Turkey in 1990s by using the vector autoregression (VAR) technique. The dynamic behaviours of each variable due to random shocks given to short-term foreign liabilities are captured by impulse response functions, and the portion of variance in the prediction for each variable in the system that is attributable to its own innovations and to shocks to other variables in the system is analysed by variance decomposition method. It is found that the policy of high interest-low exchange rate (hot money) is the main reason for the short-term capital inflows in Turkey, and we propose some main controls on capital inflows to limit some of the macroeconomic repercussions of these inflows.
24
Perry, S. F., and K. Gilmour. "AN EVALUATION OF FACTORS LIMITING CARBON DIOXIDE EXCRETION BY TROUT RED BLOOD CELLS IN VITRO." Journal of Experimental Biology 180, no. 1 (July 1, 1993): 39–54. http://dx.doi.org/10.1242/jeb.180.1.39.
Full textAbstract:
An evaluation of several potential factors limiting carbon dioxide excretion by rainbow trout (Oncorhynchus mykiss) red blood cells was performed in vitro using a recently developed radioisotopic assay. Red blood cell (RBC) CO2 excretion was reduced by pre-treatment (30 min) of blood with the carbonic anhydrase inhibitor acetazolamide (final nominal concentration 10–4 mol l-1) or the Cl-/HCO3- exchange inhibitor SITS (4-acetamido-4′-isothiocyanatostilbene-2,2′-disulphonic acid; 10-4 mol l-1). The addition of bovine carbonic anhydrase to plasma stimulated CO2 excretion in a dose-dependent manner, with maximal levels of CO2 excretion achieved at a concentration of 3 mg ml-1. These results confirmed that carbonic anhydrase activity and/or Cl-/HCO3- exchange velocity are potential limiting factors in CO2 excretion. Increasing the haematocrit elevated the rate of RBC CO2 excretion, although the effect was apparent only between 0 and 15 % haematocrit; the rate of CO2 excretion was unaffected by further increases in haematocrit between 15 and 35 %. Acute elevation of plasma HCO3- levels increased the rate of CO2 excretion in blood but not in plasma (with or without added carbonic anhydrase). These data suggest that HCO3- availability may limit CO2 excretion at higher haematocrits when the Cl-/HCO3- exchange sites are most plentiful. Lysis of RBCs and the accompanying release of intracellular carbonic anhydrase into the plasma significantly increased CO2 excretion at all haematocrit and HCO3- levels, indicating that the velocity of Cl-/HCO3- exchange does indeed limit trout RBC CO2 excretion. The addition of carbonic anhydrase (3 mg ml-1) to lysed blood caused a further increase in the rate of CO2 excretion but only at the low haematocrit of 5 %. This result suggests that the activity of RBC carbonic anhydrase does not normally limit CO2 excretion except at unusually low haematocrits, such as might occur during severe anaemia. The rapid oxygenation of partially deoxygenated blood during the 3 min assay caused a marked stimulation of CO2 excretion that was concurrent with a significant decrease of RBC intracellular pH (pHi). These data indicate that the supply of Bohr protons during the oxygenation of the blood is a key factor limiting CO2 excretion. Oxygenation of the blood prior to performing the assay also lowered RBC pHi, although CO2 excretion was actually reduced, indicating a possible specific effect of pHi on Cl-/HCO3- exchange activity or HCO3- dehydration. The results are discussed with reference to the control of carbon dioxide excretion in fish.
25
Weinstein, A. M. "Chloride transport in a mathematical model of the rat proximal tubule." American Journal of Physiology-Renal Physiology 263, no. 5 (November 1, 1992): F784—F798. http://dx.doi.org/10.1152/ajprenal.1992.263.5.f784.
Full textAbstract:
The proximal tubule model of this laboratory [Am. J. Physiol. 250 (Renal Fluid Electrolyte Physiol. 19): F860-F873, 1986] has been updated to examine proposed pathways for Cl- transport. Two additional buffer pairs have been added, i.e., HCO2-/H2CO2 and NH3/NH4+. At the luminal cell membrane Cl-/HCO2- and Cl-/HCO3- exchange are considered as pathways for Cl- entry, whereas at the peritubular membrane, Cl- exit occurs by either Na(+)-2HCO3-/Cl- exchange or K(+)-Cl- cotransport. Calculations with this model indicate that absolute proximal reabsorption of both Na+ and Cl- are critically dependent on the rate of luminal Na+/H+ exchange. In contrast, increases in the coefficient for Cl-/HCO2- exchange have little impact on overall Cl- flux, but, by enhancing base secretion, limit the depression of end-proximal HCO3-. Model calculations confirm those of Preisig and Alpern (J. Clin. Invest. 83: 1859–1867, 1989) showing that their measured value of luminal membrane H2CO2 permeability is inadequate to sustain the transcellular Cl- flux as Cl-/HCO2- exchange. Conversely, with sufficiently high H2CO2 permeability, luminal Cl- uptake is enhanced along the tubule, as HCO2- secretion and luminal acidification increase luminal H2CO2 to values severalfold greater than in glomerular filtrate. At the basolateral membrane, the thermodynamic driving force across the Na(+)-2HCO3-/Cl- exchanger is small. Although its contribution to steady-state Cl- exit may be less than the K(+)-Cl- cotransporter, the Na(+)-2HCO3-/Cl- exchanger can be a mechanism by which cytosolic acidification enhances peritubular Cl- transport, when luminal acidification enhances luminal Cl- uptake. A simulation is presented in which impermeant replacement of luminal Na+ leads to enhanced convective Cl- flux across the tight junction and alkalinization of the lateral interspace. In this setting, cytosolic Cl- depletion via the Na(+)-2HCO3-/Cl- exchanger may mimic luminal membrane Na(+)-Cl- cotransport.
26
Bao, Junwei Lucas, Xin Zhang, and Donald G. Truhlar. "Barrierless association of CF2and dissociation of C2F4by variational transition-state theory and system-specific quantum Rice–Ramsperger–Kassel theory." Proceedings of the National Academy of Sciences 113, no. 48 (November 10, 2016): 13606–11. http://dx.doi.org/10.1073/pnas.1616208113.
Full textAbstract:
Bond dissociation is a fundamental chemical reaction, and the first principles modeling of the kinetics of dissociation reactions with a monotonically increasing potential energy along the dissociation coordinate presents a challenge not only for modern electronic structure methods but also for kinetics theory. In this work, we use multifaceted variable-reaction-coordinate variational transition-state theory (VRC-VTST) to compute the high-pressure limit dissociation rate constant of tetrafluoroethylene (C2F4), in which the potential energies are computed by direct dynamics with the M08-HX exchange correlation functional. To treat the pressure dependence of the unimolecular rate constants, we use the recently developed system-specific quantum Rice–Ramsperger–Kassel theory. The calculations are carried out by direct dynamics using an exchange correlation functional validated against calculations that go beyond coupled-cluster theory with single, double, and triple excitations. Our computed dissociation rate constants agree well with the recent experimental measurements.
27
Sinha, Pankaj, and Shalini Agnihotri. "Does Brownian Risk Matter in Debt or Equity Issuance and Repurchase Decision in Indian Non-Financial Companies?" Journal of International Business and Economy 18, no. 1 (July 1, 2017): 49–69. http://dx.doi.org/10.51240/jibe.2017.1.3.
Full textAbstract:
External commercial borrowings (ECBs) of Indian non-financial firms have grown by 107 % in past few years. Looking at the high reliance of firms on external debt, this paper investigates the effect of foreign exchange, interest rate and firm specific risk on the debt issuance and retirement decision. It also investigates the factors affecting equity issuance and retirement decision of the firms. Foreign exchange risk and interest rate risk is estimated using stochastic volatility and GARCH (1,1) methods. Firm specific risk is calculated using Black-Scholes Merton model for company valuation. The results highlight that interest rate risk negatively affects the debt issuance and positively affects debt retirement decision of the firms. However, the foreign exchange risk does not affect debt issuance and retirement decision. Firm-specific risk negatively affects propensity of debt issuance of firms but plays no role in debt retirement. Foreign exchange risk, firm-specific risk, and profitability negatively affect propensity of issuance of debt to issuance of equity. This result supports the view that risky firms are more likely to finance their capital needs via new equity issues rather than by new debt issues to avoid the high-risk premium and to limit the likelihood of bankruptcy.
28
Miao, Junjie, Yuxin Fan, and Tianchi Liu. "Influence of strut on cavity at subsonic speeds: Ignition characteristics." Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 234, no. 8 (February 5, 2020): 1369–79. http://dx.doi.org/10.1177/0954410020904832.
Full textAbstract:
In high-speed airflow, the use of cavity and struts in combination can improve fuel distribution and flame-stabilization, but may weaken the ignition performance. Herein, the lean ignition characteristics of several cavity–strut flame holders in a tandem turbine-based combined cycles combustor are experimentally investigated with the flow fields by using particle image velocimetry and high-speed chemiluminescence imaging techniques. Additionally, the effects of the strut structure parameters on the lean ignition performance in the cavity are studied. Experimental results indicate that changes in structural parameters have the opposite effects on the ignition performance and the flame-propagation performance. Reducing the strut inclination angle has a contrary function with the decrease in the cavity–strut space, which also transforms the flame-stabilizing mechanism between strut-stabilizing and cavity-stabilizing, accompanied by the flame morphology behind strut changes from no-flame to intermittent-flame, and finally continuous-flame. The lean ignition limit changes with the structure parameters, mainly due to the inverse change in the mass exchange rate and cavity residence time. Compared with the single cavity, the proper cavity–strut combined structure has a wider lean ignition limit at high subsonic speeds due to the advantage of simultaneously increasing the mass exchange rate and cavity residence time.
29
VOLOSHIN, M. B. "SECOND ORDER QCD CORRECTIONS TO THE NONLEPTONIC DECAY OF THE b QUARK IN THE SLOW CHARM LIMIT." International Journal of Modern Physics A 11, no. 27 (October 30, 1996): 4931–42. http://dx.doi.org/10.1142/s0217751x96002261.
Full textAbstract:
The perturbative QCD corrections to the nonleptonic decay rate of the b quark are discussed. By considering the limit where the final charmed quarks are slow, it is argued that the coefficients of the [Formula: see text] terms, corresponding to the next-to-next-to-leading order in the standard renormalization group expansion in ln (mW/mb), are naturally large. The large coefficients arise from the final state gluon exchange between quarks and are associated with the region of rather low momenta, which may further enhance the phenomenological significance of these terms.
30
Pessôa Filho, Dalton M., Leandro O. C. Siqueira, Astor R. Simionato, Mário A. C. Espada, Daniel S. Pestana, and Fred J. DiMenna. "A Rapidly-Incremented Tethered-Swimming Test for Defining Domain-Specific Training Zones." Journal of Human Kinetics 57, no. 1 (June 22, 2017): 117–28. http://dx.doi.org/10.1515/hukin-2017-0053.
Full textAbstract:
AbstractThe purpose of this study was to investigate whether a tethered-swimming incremental test comprising small increases in resistive force applied every 60 seconds could delineate the isocapnic region during rapidly-incremented exercise. Sixteen competitive swimmers (male, n = 11; female, n = 5) performed: (a) a test to determine highest force during 30 seconds of all-out tethered swimming (Favg) and the ΔF, which represented the difference between Favg and the force required to maintain body alignment (Fbase), and (b) an incremental test beginning with 60 seconds of tethered swimming against a load that exceeded Fbase by 30% of ΔF followed by increments of 5% of ΔF every 60 seconds. This incremental test was continued until the limit of tolerance with pulmonary gas exchange (rates of oxygen uptake and carbon dioxide production) and ventilatory (rate of minute ventilation) data collected breath by breath. These data were subsequently analyzed to determine whether two breakpoints defining the isocapnic region (i.e., gas exchange threshold and respiratory compensation point) were present. We also determined the peak rate of O2 uptake and exercise economy during the incremental test. The gas exchange threshold and respiratory compensation point were observed for each test such that the associated metabolic rates, which bound the heavy-intensity domain during constant-work-rate exercise, could be determined. Significant correlations (Spearman’s) were observed for exercise economy along with (a) peak rate of oxygen uptake (ρ = .562; p < 0.025), and (b) metabolic rate at gas exchange threshold (ρ = −.759; p < 0.005). A rapidly-incremented tethered-swimming test allows for determination of the metabolic rates that define zones for domain-specific constant-work-rate training.
31
MAKOVÍNYIOVÁ, KATARÍNA, and RUDOLF ZIMKA. "On the bifurcation of limit cycles in a dynamic model of a small open economy." European Journal of Applied Mathematics 24, no. 3 (February 22, 2013): 455–70. http://dx.doi.org/10.1017/s0956792513000053.
Full textAbstract:
In this paper a four-dimensional macroeconomic model of a small open economy, describing the development of income, capital stock, interest rate and money stock, which was constructed in [5] (Makovínyiová, K. & Zimka, R. (2009) On stability in generalized Schinasi's macroeconomic model under fixed exchange rates. Tatra Mt. Math. Publ. 43, 115–122), is analysed. Sufficient conditions for the existence of one pair of purely imaginary eigenvalues and two eigenvalues with negative real parts in the linear approximation matrix of the model are found. Formulae for the calculation of the bifurcation coefficients of the model are derived. A statement about the existence of limit cycles is made. A numerical example is given illustrating the results.
32
Wang, Yuxin, and Guanying Wang. "IPO underpricing and long-term performance in China: the perspective of price limit policy." Managerial Finance 47, no. 9 (March 30, 2021): 1233–52. http://dx.doi.org/10.1108/mf-08-2020-0428.
Full textAbstract:
PurposeThe purpose of this paper is to explore how the price limit policy implemented in 2014 affects initial public offering (IPO) underpricing and long-term performance in China.Design/methodology/approachThe data are the IPOs from Shanghai Stock Exchange (SSE) and Shenzhen Stock Exchange (SZSE) between 2004 and 2018. The data are firstly divided into the IPOs before the price limit policy and the IPOs after the price limit policy according to the time of issuance. Then the two groups are divided into 4 subsamples according to the market blocks and the P/E ratio. The authors use multiple regression models to explore the effect of price limit policy in each subsample.FindingsThe first-day price limit system for IPOs is similar to the upward fuse mechanism, the purpose of which is to suppress IPO underpricing. However, this study finds that the policy does not suppress IPO underpricing, but increases the underpricing rate in all subsamples. Besides, the long-term performance in each subsample is different from each other. Main Board stocks’ long-term performance is worse after the policy. The policy makes Small and Medium Enterprise Board (SME Board) and Growth Enterprise Market Board (GEM Board) stocks with high P/E ratios perform better in the long term. For SME Board and GEM Board stocks with low P/E ratios, the policy makes no significant effect.Practical implicationsGood policy intentions may sometimes lead to counterproductive effects. However, since the long-term performance of each subsample is different, it is difficult to judge whether the policy should continue to be implemented or cancelled. Implementing different policies for different subsamples may be a better way to solve this problem.Originality/valueThis paper contributes to the study of IPO underpricing and long-term performance from the perspective of price limit policy.
33
Kleidon, A., M. Renner, and P. Porada. "Estimates of the climatological land surface energy and water balance derived from maximum convective power." Hydrology and Earth System Sciences 18, no. 6 (June 17, 2014): 2201–18. http://dx.doi.org/10.5194/hess-18-2201-2014.
Full textAbstract:
Abstract. The land surface energy and water balances are tightly coupled by the partitioning of absorbed solar radiation into terrestrial radiation and the turbulent fluxes of sensible and latent heat, as well as the partitioning of precipitation into evaporation and runoff. Evaporation forms the critical link between these two balances. Its rate is strongly affected by turbulent exchange as it provides the means to efficiently exchange moisture between the heated, moist surface and the cooled, dry atmosphere. Here, we use the constraint that this mass exchange operates at the thermodynamic limit of maximum power to derive analytical expressions for the partitioning of the surface energy and water balances on land. We use satellite-derived forcing of absorbed solar radiation, surface temperature and precipitation to derive simple spatial estimates for the annual mean fluxes of sensible and latent heat and evaluate these estimates with the ERA-Interim reanalysis data set and observations of the discharge of large river basins. Given the extremely simple approach, we find that our estimates explain the climatic mean variations in net radiation, evaporation, and river discharge reasonably well. We conclude that our analytical, minimum approach provides adequate first order estimates of the surface energy and water balance on land and that the thermodynamic limit of maximum power provides a useful closure assumption to constrain the energy partitioning at the land surface.
34
Kleidon, A., M. Renner, and P. Porada. "Estimates of the climatological land surface energy and water balance derived from maximum convective power." Hydrology and Earth System Sciences Discussions 11, no. 1 (January 8, 2014): 265–306. http://dx.doi.org/10.5194/hessd-11-265-2014.
Full textAbstract:
Abstract. The land surface energy- and water balances are tightly coupled by the partitioning of absorbed solar radiation into terrestrial radiation and the turbulent fluxes of sensible and latent heat, as well as the partitioning of precipitation into evaporation and runoff. Evaporation forms the critical link between these two balances. Its rate is strongly affected by turbulent exchange as it provides the means to efficiently exchange moisture between the heated, moist surface and the cooled, dry atmosphere. Here, we use the constraint that this mass exchange operates at the thermodynamic limit of maximum power to derive analytical expressions for the partitioning of the surface energy- and water balances on land. We use satellite-derived forcing of absorbed solar radiation, surface temperature and precipitation to derive simple spatial estimates for the annual mean fluxes of sensible and latent heat and evaluate these estimates with the ERA-Interim reanalysis dataset and observations of the discharge of large river basins. Given the extremely simple approach, we find that our estimates explain the climatic mean variations in net radiation, evaporation, and river discharge reasonably well. We conclude that our analytical, minimum approach provides adequate first order estimates of the surface energy- and water balance on land and that the thermodynamic limit of maximum power provides a useful closure assumption to constrain the energy partitioning at the land surface.
35
Schechter, Ido, J. T. A. Proctor, and D. C. Elfving. "THE EFFECT OF CROP LOAD ON FRUIT DRY WEIGHT AND DRY WEIGHT CONTENT, SPECIFIC LEAF WEIGHT, AND LEAF CARBON EXCHANGE." HortScience 27, no. 6 (June 1992): 625c—625. http://dx.doi.org/10.21273/hortsci.27.6.625c.
Full textAbstract:
Mature apple trees (Malus domestica Borkh.) were studied in the 1989 and 1990 seasons to explore the effect of differential crop load on fruit dry weight (DW), DW content, specific leaf weight, and leaf carbon exchange, using girdled and non-girdled limbs. Fruit DW and DW content decreased with heavier fruit loads, however, fruit on girdled limbs had higher fruit DW and DW content. Specific leaf weight did not differ in leaves on non-girdled limbs along the crop load gradient, but increased dramatically in leaves on girdled limbs with crop load lighter than one fruit per cm2 cross-sectional area. These leaves also had a low photosynthetic rate, high stomatal resistance, and high internal CO2 concentration. The results suggest a physiological limit for photoassimilate usage by the tree. Exceeding this limit by reducing sink strength resulted in excessive carbohydrate accumulation in leaves, causing physical damage to the photosystem.
36
Fasching, Patrick, Stefan Rinnerhofer, Georg Wultsch, Philipp Birnbaumer, and Peter Hofmann. "The First Lactate Threshold Is a Limit for Heavy Occupational Work." Journal of Functional Morphology and Kinesiology 5, no. 3 (August 25, 2020): 66. http://dx.doi.org/10.3390/jfmk5030066.
Full textAbstract:
Long-term heavy physical work often leads to early retirement and disability pension due to chronic overload, with a need to define upper limits. The aim of this study was to evaluate the value of the first lactate threshold (LTP1) as a physiological marker for heavy occupational work. A total of 188 male and 52 female workers performed an incremental cycle ergometer test to determine maximal exercise performance and the first and second lactate (LTP1; LTP2) and ventilatory thresholds (VT1; VT2). Heart rate (HR) recordings were obtained during one eight-hour shift (HR8h) and oxygen uptake was measured during 20 minutes of a representative work phase. Energy expenditure (EE) was calculated from gas-exchange measures. Maximal power output (Pmax), maximal oxygen consumption (VO2 max) and power output at LTP1 and LTP2 were significantly different between male and female workers. HR8h was not significantly different between male and female workers. A significant relationship was found between Pmax and power output at LTP1. HR8h as a percentage of maximum HR significantly declined with increasing performance (Pmax:r = −0.56; p < 0.01; PLTP1:r = −0.49; p < 0.01). Despite different cardio-respiratory fitness-levels; 95.4% of all workers performed their usual work below LTP1. It is therefore suggested that LTP1 represents the upper limit for sustained heavy occupational work; which supports its use to determine work capability and assessing the limits of heavy occupational work.
37
FINNIGAN, T. D., and G. N. IVEY. "Convectively driven exchange flow in a stratified sill-enclosed basin." Journal of Fluid Mechanics 418 (September 10, 2000): 313–38. http://dx.doi.org/10.1017/s0022112000001130.
Full textAbstract:
Laboratory experiments are used to investigate the processes governing steady convectively driven circulation in a basin that communicates with a large external reservoir over a shallow sill. The motion is maintained by a steady loss of buoyancy distributed over the surface of the basin. Turbulent convection associated with the forcing produces a horizontal buoyancy gradient across the sill and the resulting mean flow consists of a layer directed into the basin near the surface with a dense counter flow below.To first order, the magnitude of the exchange flow over the sill is determined by the horizontal momentum balance within the basin. Measurements of the mean and turbulent flow fields are used to show that inertia, buoyancy and friction may each contribute significantly to the balance. The interior flow produces a horizontal pressure gradient near the surface which must also contribute to the momentum balance. The density of the lower layer at the sill reflects the cumulative effect of interior processes, such as mixing, and these in turn influence the hydraulically controlled exchange flow over the sill. The basin dynamics are therefore coupled in a nonlinear fashion with the submaximal sill exchange. This coupling is investigated first by showing how interior processes are affected by changes in the magnitude of the forcing, and then by observing the associated variation of the flow state at the sill. The flow state is defined in terms of its relative proximity to the theoretical maximal exchange limit. Results show that the exchange flows are submaximal with flow rate approximately 85% of the maximal limit. This state appears to change very little in response to increasing forcing.For a stratified basin, which exhibits a deep stagnant layer under the convectively driven near-surface exchange flow, the possibility of basin ventilation or erosion of deep fluid exists in the long term. This process and its dependence on external parameters is also explored.
38
Hua, Kang, Xueliu Xu, Zhiping Luo, Dong Fang, Rui Bao, and Jianhong Yi. "Effective Removal of Mercury Ions in Aqueous Solutions: A Review." Current Nanoscience 16, no. 3 (April 2, 2020): 363–75. http://dx.doi.org/10.2174/1573413715666190112110659.
Full textAbstract:
Background: Due to its high toxicity and bioaccumulation, the existence of mercury in the environment is always a big threat to human beings. In order to control mercury pollution, scientists have put great efforts in the past decades. Methods: Precipitation, adsorption, membrane separation, biological treatment and ion exchange are reviewed as a remover for mercury removal. For each material type, we not only reported on the removal mechanism, but also discussed the best areas for it. The correlation method and step-to-step focusing method have been used for references. Conclusion: With the exploration and application of research, people have mastered a variety of mature technologies for the treatment of mercury-containing wastewater. Using inexpensive adsorbents is a cost-effective method for treating low concentrations of heavy metal wastewater. Ion exchange with a fast removal rate has been widely used in the field of heavy metal removal from wastewater. The biological treatment method can effectively treat low-concentration mercurycontaining wastewater. However, there is still a need to develop novel mercury removers with high capacity, fast removal rate, and low removal limit. Nanomaterials with a high specific surface area on substrate with synergistic effects, such as high adsorption and ion exchange, are the future research points.
39
Janssens, Michiel Etienne, and Stuart Wakelin. "Centrifugal and Membrane Therapeutic Plasma Exchange – A Mini-review." European Oncology & Haematology 14, no. 2 (2018): 105. http://dx.doi.org/10.17925/eoh.2018.14.2.105.
Full textAbstract:
During therapeutic plasma exchange (TPE), a large volume of a patient’s plasma is separated from the cellular components of the blood and replaced with appropriate fluids to remove circulating plasma components and disease mediators such as antibodies, cholesterol, toxins and drugs. Automated TPE systems can be categorised into two distinct groups based on the method of plasma separation: centrifugal TPE (cTPE) and membrane filtration TPE (mTPE). While technical and performance parameters for various TPE systems have been reported previously, the recent publication of several head-to-head studies directly comparing the Spectra Optia® cTPE system (Terumo BCT, Lakewood, CO, US) with mTPE systems has increased the understanding of their performance. This review summarises the comparative information between the systems. Although both device types are well tolerated, the majority of technical variables favour the cTPE system over mTPE systems, with a low risk of clotting events and benefits in plasma removal efficiency and hence procedure time. Platelet loss with the cTPE system was also shown to be similar or reduced compared with mTPE systems. Finally, flow rate requirements limit the use of peripheral venous access with mTPE devices, but not cTPE devices. Conclusively, several important differences exist between cTPE and mTPE systems that may influence treatment decisions.
40
Musterman, J. L., and T. H. Flippin. "Treatability Studies and Process Design for Toxicity Reduction for a Synthetic Fiber Industry." Water Science and Technology 29, no. 9 (May 1, 1994): 297–306. http://dx.doi.org/10.2166/wst.1994.0497.
Full textAbstract:
A series of batch treatability screening tests were conducted to identify technologies suitable for removal of ethylenediamine (EDA) and aquatic toxicity in a wastewater discharge from a synthetic fiber plant. Air stripping, cation exchange resin, activated silica, macroreticular resin, granular activated carbon and bio-hydrolysis were evaluated. Only cation exchange resin and bio-hydrolysis reduced effluent toxicity to the required limit. Continuous flow bench-scale activated sludge treatability tests were conducted over a four month period under simulated warm and cold weather operating conditions. The results confirmed that activated sludge treatment alone could consistently provide greater than 95 percent BOD reduction and complete EDA hydrolysis, nitrification and toxicity reduction. Toxicity reduction could be accomplished at high organic loading (F/M > 1.0/day) but hydrolysis of EDA caused an effluent NH3-N concentration of greater than 300 mg/L. A lower organic loading (F/M <0.30/day) was therefore selected to provide nitrification for compliance with the 25 mg/L NH3-N pretreatment limit. Alternatively, a high rate activated sludge system (F/M > 1.0/day) coupled with high pH air stripping of ammonia was considered in “desktop” evaluations. A detailed process design and cost estimate were developed.
41
OOI, SENG KEAT, GEORGE CONSTANTINESCU, and LARRY WEBER. "Numerical simulations of lock-exchange compositional gravity current." Journal of Fluid Mechanics 635 (September 10, 2009): 361–88. http://dx.doi.org/10.1017/s0022112009007599.
Full textAbstract:
Compositional gravity current flows produced by the instantaneous release of a finite-volume, heavier lock fluid in a rectangular horizontal plane channel are investigated using large eddy simulation. The first part of the paper focuses on the evolution of Boussinesq lock-exchange gravity currents with a large initial volume of the release during the slumping phase in which the front of the gravity current propagates with constant speed. High-resolution simulations are conducted for Grashof numbers $\sqrt {Gr}$ = 3150 (LGR simulation) and $\sqrt {Gr}$ = 126000 (HGR simulation). The Grashof number is defined with the channel depth h and the buoyancy velocity ub = $\sqrt {g'h}$ (g′ is the reduced gravity). In the HGR simulation the flow is turbulent in the regions behind the two fronts. Compared to the LGR simulation, the interfacial billows lose their coherence much more rapidly (over less than 2.5h behind the front), which results in a much faster decay of the large-scale content and turbulence intensity in the trailing regions of the flow. A slightly tilted, stably stratified interface layer develops away from the two fronts. The concentration profiles across this layer can be approximated by a hyperbolic tangent function. In the HGR simulation the energy budget shows that for t > 18h/ub the flow reaches a regime in which the total dissipation rate and the rates of change of the total potential and kinetic energies are constant in time. The second part of the paper focuses on the study of the transition of Boussinesq gravity currents with a small initial volume of the release to the buoyancy–inertia self-similar phase. When the existence of the back wall is communicated to the front, the front speed starts to decrease, and the current transitions to the buoyancy–inertia phase. Three high-resolution simulations are performed at Grashof numbers between $\sqrt {Gr}$ = 3 × 104 and $\sqrt {Gr}$ = 9 × 104. Additionally, a calculation at a much higher Grashof number ($\sqrt {Gr}$ = 106) is performed to understand the behaviour of a bottom-propagating current closer to the inviscid limit. The three-dimensional simulations correctly predict a front speed decrease proportional to t−α (the time t is measured from the release time) over the buoyancy–inertia phase, with the constant α approaching the theoretical value of 1/3 as the current approaches the inviscid limit. At Grashof numbers for which $\sqrt {Gr}$ > 3 × 104, the intensity of the turbulence in the near-wall region behind the front is large enough to induce the formation of a region containing streaks of low and high streamwise velocities. The streaks are present well into the buoyancy–inertia phase before the speed of the front decays below values at which the streaks can be sustained. The formation of the velocity streaks induces a streaky distribution of the bed friction velocity in the region immediately behind the front. This distribution becomes finer as the Grashof number increases. For simulations in which the only difference was the value of the Grashof number ($\sqrt {Gr}$ = 4.7 × 104 versus $\sqrt {Gr}$ = 106), analysis of the non-dimensional bed friction velocity distributions shows that the capacity of the gravity current to entrain sediment from the bed increases with the Grashof number. Past the later stages of the transition to the buoyancy–inertia phase, the temporal variations of the potential energy, the kinetic energy and the integral of the total dissipation rate are logarithmic.
42
Yu, Tang-Qing, Jianfeng Lu, Cameron F. Abrams, and Eric Vanden-Eijnden. "Multiscale implementation of infinite-swap replica exchange molecular dynamics." Proceedings of the National Academy of Sciences 113, no. 42 (October 3, 2016): 11744–49. http://dx.doi.org/10.1073/pnas.1605089113.
Full textAbstract:
Replica exchange molecular dynamics (REMD) is a popular method to accelerate conformational sampling of complex molecular systems. The idea is to run several replicas of the system in parallel at different temperatures that are swapped periodically. These swaps are typically attempted every few MD steps and accepted or rejected according to a Metropolis–Hastings criterion. This guarantees that the joint distribution of the composite system of replicas is the normalized sum of the symmetrized product of the canonical distributions of these replicas at the different temperatures. Here we propose a different implementation of REMD in which (i) the swaps obey a continuous-time Markov jump process implemented via Gillespie’s stochastic simulation algorithm (SSA), which also samples exactly the aforementioned joint distribution and has the advantage of being rejection free, and (ii) this REMD-SSA is combined with the heterogeneous multiscale method to accelerate the rate of the swaps and reach the so-called infinite-swap limit that is known to optimize sampling efficiency. The method is easy to implement and can be trivially parallelized. Here we illustrate its accuracy and efficiency on the examples of alanine dipeptide in vacuum and C-terminal β-hairpin of protein G in explicit solvent. In this latter example, our results indicate that the landscape of the protein is a triple funnel with two folded structures and one misfolded structure that are stabilized by H-bonds.
43
Li, Huiquan, and Jiancheng Wang. "Towards the merger of Hawking radiating black holes." International Journal of Modern Physics D 30, no. 08 (April 29, 2021): 2150060. http://dx.doi.org/10.1142/s0218271821500607.
Full textAbstract:
We discuss the merger process of binary black holes with Hawking radiation taken into account. Besides the redshifted radiation to infinity, binary black holes can exchange radiation between themselves, which is first redshifted and then blueshifted when it propagates from one hole to the other. The exchange rate should be large when the temperature-divergent horizons are penetrating each other to form a single horizon with unique temperature. This will cause nonnegligible mass and angular momentum transfer between the black holes during the merging process of the horizons. We further argue in the large mass ratio limit that the light hole whose local evaporation is enhanced by the competing redshift–blueshift effects will probably evaporate or decay completely before reaching the horizon of the heavy one. We also discuss the possibility of testing Hawking radiation and even exploring the information loss puzzle in gravitational wave observations.
44
bt Rosn, Nurrul Akmar, Hawa bt Jaafar, and Nur Harapan bt Mohd Ghazali. "Leaf Gas Exchange Attributes and Quality Performance of Kacip Fatimah (Labisia Pumila Blume) Under Different Sources of Organic and Inorganic Fertilizers." Journal of Agriculture and Crops, no. 511 (November 2, 2019): 211–25. http://dx.doi.org/10.32861/jac.511.218.225.
Full textAbstract:
An experiment was designed with Randomized Complete Block Designed to investigate the effects of organic and inorganic nitrogen fertilizer at 90 kg N/ha on growth and leaf gas exchange in two varieties of Labisia pumila at 15 weeks after transplanting (WAT). In this study total biomass and photosynthesis (A) were significantly (P≤0.05) different among all factor. The results indicated that chicken manure enhanced the net photosynthetic rate (11.10 µmol/m²/s), stomatal conductance (0.40 mmol/m/s) and transpiration rate (5.30 mmol/m²/s) of L.pumila significantly after 31 weeks of planting. Chicken manure and Gobi indicated higher accumulation on total phenolic and total flavonoid compared to NPK green and control. Organic fertilizers (chicken manure and Gobi) were positively influenced the leaf gas exchange and growth of L.pumila as compared to the NPK green and control. This study proved that organic fertilizer can produce a quality of L. pumila compared to NPK green. Based on the principle of organic fertilizer which is slowly release from organic fertilizer will limit the nutrient availability for plant growth and allocate more carbon to produce secondary metabolites.
45
Suanto, Ricky, and Yanuar Yanuar. "Analisa Pengaruh Perubahan Fed Fund Rate, Index Harga Saham Gabungan dan Indeks LQ45 Terhadap Nilai Tukar Dollar Amerika – Rupiah." Jurnal Manajemen Bisnis dan Kewirausahaan 4, no. 3 (May 21, 2020): 12. http://dx.doi.org/10.24912/jmbk.v4i3.7909.
Full textAbstract:
The economy in Indonesia is experiencing a decline which can be seen from the decline in the Composite Stock Price Index in Indonesia. The decline in the value of the Composite Stock Price Index and Liquid 45 Index (LQ45) affected the rupiah exchange rate against US dollars that have passed the psychological level limit of Rp. 15,000 per 1 USD. The weakening of the rupiah and the index value of the stock was triggered by an increase in interest rates set by the Federal which increase Fed Fund Rate to 2.25% in September 2018.This study aims to explain whether it is true that the announcement of changes in the central bank's fed funds rate in the United States can be related and influence the Stock Price Index and Exchange Rates in other countries, especially in Indonesia.After collecting and processing data with Path Analysis, the results show that the impact in average of the fed fund rate to the average return LQ45 index has the strongest effect compared to other variables, then the strongest effect value is produced by the effect of average return Composite Stock Price Index to the average return of the US Dollar - Rupiah which is negative 0.76. After going through the mediation process, the indirect effect that occurs between the average fed fund rate on the average return of the US Dollar – Rupiah is positive 0.451, which significantly stagnant and changes the direction of the effect compared to its direct effect of negative 0.46.
46
BEKE, G. J. "SOIL DEVELOPMENT IN A 100-YEAR-OLD DIKE NEAR GRAND PRÉ, NOVA SCOTIA." Canadian Journal of Soil Science 70, no. 4 (November 1, 1990): 683–92. http://dx.doi.org/10.4141/cjss90-070.
Full textAbstract:
The morphology and composition were studied of a pair of soil profiles that had developed in a dike which was constructed 100 yr ago from marine sediments of silty clay loam texture. Both profiles had a weakly expressed A-B-C horizon sequence and strong structural development. They had Bm horizons and their exchange complex was dominated by magnesium ions. Organic carbon had accumulated in the surface mineral horizon at a maximum rate of 26.3 g m−2 yr−1. Adverse climatic conditions, typical for this and similar site locations, appeared to impose a limit on soil development. Key words: Soil formation, marine sediments, maritime climate
47
Buffie, Edward F., and Luis-Felipe Zanna. "LIMITED ASSET MARKET PARTICIPATION AND DETERMINACY IN THE OPEN ECONOMY." Macroeconomic Dynamics 22, no. 8 (December 2018): 1937–77. http://dx.doi.org/10.1017/s1365100516000961.
Full textAbstract:
The perception that inflation targeting (IT) runs a high risk of indeterminacy when a significant share of households are too poor to save is an artifact of the closed economy. In the open economy, the Taylor principle is generally valid for both contemporaneous and forward-looking IT. Active policy in contemporaneous IT guarantees determinacy, eccentric cases aside. In forward-looking IT, the scope for active policy is constrained by an upper bound on the Taylor coefficient. The upper bound is insensitive, however, to the share of poor, nonsaving households. Moreover, it can be increased substantially–to a level that does not bind–through reserve sales/purchases that limit exchange rate volatility.
48
van Iersel, Marc W., and Orville M. Lindstrom. "Temperature Response of Whole-plant CO2 Exchange Rates of Three Magnolia Cultivars." Journal of the American Society for Horticultural Science 124, no. 3 (May 1999): 277–82. http://dx.doi.org/10.21273/jashs.124.3.277.
Full textAbstract:
Temperature-response curves for photosynthesis and respiration are useful in predicting the ability of plants to perform under different environmental conditions. Whole crop CO2 exchange rates of three magnolia (Magnolia grandiflora L.) cultivars (`MGTIG', `Little Gem', and `Claudia Wannamaker') were measured over a 25 °C temperature range. Plants were exposed to cool temperatures (13 °C day, 3 °C night) temperatures before the measurements. Net photosynthesis (Pnet) of all three cultivars increased from 3 to 15 °C and decreased again at higher temperatures. `MGTIG' had the highest and `Little Gem' the lowest Pnet, irrespective of temperature. The Q10 (relative increase in the rate of a process with a 10 °C increase in temperature) for Pnet of all three cultivars decreased over the entire temperature range. `MGTIG' had the lowest Q10 at low temperatures (1.4 at 8 °C), while `Little Gem' had the lowest Q10 for Pnet at temperatures >17 °C and a negative Q10 > 23 °C. This indicates a rapid decline in Pnet of `Little Gem' at high temperatures. The decrease in Pnet of all three cultivars at temperatures >15 °C was caused mainly by an exponential increase in dark respiration (Rdark) with increasing temperature. `Little Gem' had a lower Rdark (per unit fresh mass) than `MGTIG' or `Claudia Wannamaker', but all three cultivars had a similar Q10 (2.46). Gross photosynthesis (Pgross) was less sensitive to temperature than Pnet and Rdark. The optimal temperature for Pgross of `MGTIG' was lower (19 °C) than those of `Little Gem' (21 °C) and `Claudia Wannamaker' (22 °C). The Q10 for Pgross decreased with increasing temperature, and was lower for `MGTIG' than for `Little Gem' and `Claudia Wannamaker'. All three cultivars had the same optimal temperature (11 °C) for net assimilation rate (NAR), and NAR was not very sensitive to temperature changes from 3 to 17 °C. This indicates that the plants were well-adapted to their environmental conditions. The results suggest that respiration rate may limit magnolia growth when temperatures get high in winter time.
49
Albasoos, Hani, and Hanan Hanan Al-Hadhrami. "China-U.S. Currency Conflict." International Journal of Research in Business and Social Science (2147-4478) 5, no. 6 (October 20, 2016): 40–50. http://dx.doi.org/10.20525/ijrbs.v5i6.575.
Full textAbstract:
For more than a decade, China has a policy of managing its currency exchange rate (RMB) to limit its appreciation against other currencies like U.S dollar. This policy has been subjected to many criticisms from United States’ lawmakers as currency manipulation. The U.S. argues that China is gaining an advantage of export and attracting direct foreign investment at the expense of other countries including the United State. The claim also has included that China’s manipulation causes U.S. trade deficit as well as high rate of unemployment. Meanwhile, China’s policy makers argue that its policy of exchange rate is a mechanism tool to enhance the development of the country and attaining market growth to make China rich and powerful. This research paper underlines the root of this argument and how china’s currency policy has affected both economics of U.S. and China. Many economists have emphasized on the appreciation of RMB as an important factor to attain the trade balance. However, this research argues that the appreciation is not going to matter. Pressure has been put on Obama’s Administration to push China to appreciate its currency and to designate China as a "currency manipulator". Several Bills have been introduced to discuss this issue.From a legal perspective, two entities could tackle this issue. They are the World Trade Organization (WTO) and the International Monetary Fund (IMF). However, IMF lack legitimacy and leverage and WTO has no jurisdiction over the exchange rate. So, none of these entities could handle the currency issue. Therefore, this paper analyzes some possible solutions such as Omnibus Act, tariffs, import quotas and forming new legislation. Where, it concludes that the best solution could be via forming a new international agency.
50
Nodzeński, Adam. "A Method for the Measurement of Carbon Dioxide Desorption from Coal in the Elevated Pressure Range." Adsorption Science & Technology 13, no. 2 (April 1996): 71–84. http://dx.doi.org/10.1177/026361749601300201.
Full textAbstract:
During the liberation of gas from a coal bed, the temperature of the system is decreased because desorption is an endothermic process and heat exchange with the surroundings is difficult. A method for measuring gas desorption in the elevated pressure range, enabling investigations under isothermal and quasi-adiabatic conditions, was described. The results of carbon dioxide desorption from Polish coal were presented. The study was carried out using different rates of decrease in the external gas pressure for different coal grain sizes. The non-isothermal desorption curves thus obtained were described using empirical equations. Extrapolation of the equation constants obtained enabled the desorption curves to be calculated for the limit of decrease in rate of the external gas pressure and of grain size. It was found experimentally that the dependence of the decrease in coal temperature on the amount of desorbed gas is linear provided that heat exchange with the surroundings is limited.