A Short-Term Cloud Forecast Scheme Using Cross Correlations

In this paper, we investigate the relationship between unexpected information from postings and news, and the unexpected information is measured by the residual of regressions of trading volume on numbers of news or postings. We mainly find that (i) There are significant positive contemporaneous correlations between the unexpected information coming from postings and different kinds of news; the correlation between the unexpected information coming from postings and new media news is stronger than that between the unexpected information coming from postings and mass media news; (ii) The unexpected information coming from postings could cause the unexpected information coming from news, but only the unexpected information coming from the mass media news could cause that coming from postings; (iii) There are persistent power-law cross-correlations between the unexpected information coming from postings and that coming from mass media news and new media news. The cross-correlation between the unexpected information coming from postings and new media news is more persistent than the one between the unexpected information coming from postings and mass media news. The cross-correlations are all more stable in long term than in short term. We attribute our findings above to the dissemination speed of the information on the Internet.

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Dynamic Cross-Correlations between Investors’ Attention and CSI300 Index Futures

Fluctuation and Noise Letters ◽

10.1142/s0219477519500226 ◽

2019 ◽

Vol 18 (04) ◽

pp. 1950022

Author(s):

Xiong Xiong ◽

Kewei Xu ◽

Dehua Shen

Keyword(s):

Cross Correlation ◽

Futures Market ◽

Relative Activity ◽

Short Term ◽

Index Futures ◽

Search Volume ◽

Cross Correlation Analysis ◽

Cross Correlations ◽

The Cross

Using search volume on Baidu Index as the proxy for investors’ attention, we investigate the dynamic nonlinear relationship between investors’ attention and CSI300 index futures market. Multifractal detrend cross-correlation analysis (MF-DCCA) is employed to explore the multifractal features of the cross-correlations between investors’ attention and the return and relative activity of index futures market. We find that the power-law cross-correlations between investors’ attention and CSI300 index futures market are stronger in the short term than in the long term, and the cross-correlations are significantly multifractal. Precisely, the cross-correlation between abnormal search volume (ASV) and the relative activity is persistent, and the cross-correlation between ASV and return of IF is persistent in the short term but weakly anti-persistent in the long term. Besides, we also find that, with the restriction on index futures market, the cross-correlations between investors’ attention and CSI300 index futures market become less stable.

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The Vegetation–Climate System Complexity through Recurrence Analysis

Entropy ◽

10.3390/e23050559 ◽

2021 ◽

Vol 23 (5) ◽

pp. 559

Author(s):

Andrés F. Almeida-Ñauñay ◽

Rosa María Benito ◽

Miguel Quemada ◽

Juan Carlos Losada ◽

Ana M. Tarquis

Keyword(s):

Cross Correlation ◽

Temporal Dynamics ◽

Vegetation Indices ◽

Climatic Variable ◽

Recurrence Plots ◽

Short Term ◽

Temperature And Precipitation ◽

Cross Correlation Analysis ◽

Mediterranean Grasslands ◽

Cross Correlations

Multiple studies revealed that pasture grasslands are a time-varying complex ecological system. Climate variables regulate vegetation growing, being precipitation and temperature the most critical driver factors. This work aims to assess the response of two different Vegetation Indices (VIs) to the temporal dynamics of temperature and precipitation in a semiarid area. Two Mediterranean grasslands zones situated in the center of Spain were selected to accomplish this goal. Correlations and cross-correlations between VI and each climatic variable were computed. Different lagged responses of each VIs series were detected, varying in zones, the year’s season, and the climatic variable. Recurrence Plots (RPs) and Cross Recurrence Plots (CRPs) analyses were applied to characterise and quantify the system’s complexity showed in the cross-correlation analysis. RPs pointed out that short-term predictability and high dimensionality of VIs series, as well as precipitation, characterised this dynamic. Meanwhile, temperature showed a more regular pattern and lower dimensionality. CRPs revealed that precipitation was a critical variable to distinguish between zones due to their complex pattern and influence on the soil’s water balance that the VI reflects. Overall, we prove RP and CRP’s potential as adequate tools for analysing vegetation dynamics characterised by complexity.

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Cross-Correlations between Energy and Emissions Markets: New Evidence from Fractal and Multifractal Analysis

Mathematical Problems in Engineering ◽

10.1155/2014/197069 ◽

2014 ◽

Vol 2014 ◽

pp. 1-13 ◽

Cited By ~ 5

Author(s):

Gang-Jin Wang ◽

Chi Xie ◽

Shou Chen ◽

Feng Han

Keyword(s):

Multifractal Analysis ◽

Cross Correlation ◽

Market Dynamics ◽

Gas Oil ◽

Short Term ◽

Cross Correlation Analysis ◽

Cross Correlations ◽

Rolling Windows ◽

Oil Gas

We supply a new perspective to describe and understand the behavior of cross-correlations between energy and emissions markets. Namely, we investigate cross-correlations between oil and gas (Oil-Gas), oil and CO2(Oil-CO2), and gas andCO2(Gas-CO2) based on fractal and multifractal analysis. We focus our study on returns of the oil, gas, andCO2during the period of April 22, 2005–April 30, 2013. In the empirical analysis, by using the detrended cross-correlation analysis (DCCA) method, we find that cross-correlations for Oil-Gas, Oil-CO2, and Gas-CO2obey a power-law and are weakly persistent. Then, we adopt the method of DCCA cross-correlation coefficient to quantify cross-correlations between energy and emissions markets. The results show that their cross-correlations are diverse at different time scales. Next, based on the multifractal DCCA method, we find that cross-correlated markets have the nonlinear and multifractal nature and that the multifractality strength for three cross-correlated markets is arranged in the order of Gas-CO2 > Oil-Gas > Oil-CO2. Finally, by employing the rolling windows method, which can be used to investigate time-varying cross-correlation scaling exponents, we analyze short-term and long-term market dynamics and find that the recent global financial crisis has a notable influence on short-term and long-term market dynamics.

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Dynamic Cross-Correlations between Participants’ Attentions to P2P Lending and Offline Loan in the Private Lending Market

Complexity ◽

10.1155/2019/1635793 ◽

2019 ◽

Vol 2019 ◽

pp. 1-8

Author(s):

Yingxiu Zhao ◽

Wei Zhang ◽

Xiangyu Kong

Keyword(s):

Correlation Analysis ◽

Power Law ◽

Cross Correlation ◽

Granger Causality Test ◽

Short Term ◽

Causality Test ◽

Cross Correlation Analysis ◽

Private Lending ◽

P2p Lending ◽

Cross Correlations

In this paper, we examine the dynamic cross-correlations between participants’ attentions to the P2P lending and offline loan (lending) with the method of multifractal detrended cross-correlation analysis (MF-DCCA). The empirical result mainly shows that (1) the power-law cross-correlation exists between participants’ attentions to the P2P lending and offline loan and is persistent, (2) the cross-correlation is more stable in the short term, and (3) the relation subjected to a small fluctuation is more cross-correlated than that under larger ones. Furthermore, we carry out the robustness test to verify the result. The Granger causality test indicates that participants’ attentions to P2P lending and offline loan Granger cause each other in the short term.

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Short-Term Fluctuations of Sugar Beet Damping-Off by Pythium ultimum in Relation to Changes in Bacterial Communities After Organic Amendments to Two Soils

Phytopathology ◽

10.1094/phyto-07-11-0189 ◽

2012 ◽

Vol 102 (4) ◽

pp. 413-420 ◽

Cited By ~ 20

Author(s):

Miaomiao He ◽

Guangming Tian ◽

Alexander M. Semenov ◽

Ariena H. C. van Bruggen

Keyword(s):

Bacterial Communities ◽

Pythium Ultimum ◽

Dna Fragments ◽

Emission Rates ◽

Damping Off ◽

Microbial Activities ◽

Short Term ◽

Low Intensity ◽

Cross Correlations ◽

Copiotrophic Bacteria

Previously, oscillations in beet seedling damping-off by Pythium ultimum, measured as area under the disease progress curve (AUDPC), were demonstrated after incorporation of organic materials into organic and conventional soils. These periodic fluctuations of P. ultimum infections were cross-correlated with oscillations of copiotrophic CFU at lags of 2 to 4 days. For this article, we investigated whether bacterial communities and microbial activities fluctuated after a disturbance from incorporation of organic materials, and whether these fluctuations were linked to the short-term oscillations in AUDPC of beet seedling damping-off and bacterial populations (CFU) in soil. Soil microbial communities studied by polymerase chain reaction-DGGE analysis of 16S DNA after isolation of total DNA from soil and microbial activities measured as CO2 emission rates were monitored daily for 14 days after addition of grass-clover (GC) or composted manure (CM) into organic versus conventional soils. Similar to our previous findings, AUDPC and density of copiotrophic bacteria oscillated with time. Fluctuations in species richness (S), Shannon diversity index (H), and individual amplicons on DGGE gels were also detected. Oscillations in AUDPC were positively cross-correlated with copiotrophic CFU in all soils. Oscillations in AUDPC were also positively cross-correlated with 19 to 35% of the high-intensity DNA fragments in soils amended with GC but only 2 to 3% of these fragments in CM-amended soils. AUDPC values were negatively cross-correlated with 13 to 17% of the amplicons with low average intensities in CM-amended soils, which were not correlated with densities of copiotrophic CFU. CO2 emission rates had remarkable variations in the initial 7 days after either of the soil amendments but were not associated with daily changes in AUDPC. The results suggest that infection by P. ultimum is hampered by competition from culturable copiotrophic bacteria and some high-intensity DGGE amplicons, because AUDPC is cross-correlated with these variables at lags of 1 to 4 days. However, negative cross-correlations with low-intensity DNA fragments indicate that P. ultimum infection could also be suppressed by antagonistic bacteria with low densities that may be nonculturable species, especially in CM amended soil. The organic soil generally had lower AUDPC values, higher bacterial diversity, and negative cross-correlations between AUDPC and low-intensity DNA fragments (after CM amendment), indicating that specific bacteria that do not attain high densities may contribute to P. ultimum suppression in organic soils.

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Conceptual short-term memory (CSTM) supports core claims of Christiansen and Chater

Behavioral and Brain Sciences ◽

10.1017/s0140525x15000928 ◽

2016 ◽

Vol 39 ◽

Author(s):

Mary C. Potter

Keyword(s):

Working Memory ◽

Rapid Serial Visual Presentation ◽

Language Comprehension ◽

Short Term Memory ◽

Visual Presentation ◽

Long Term Memory ◽

Short Term ◽

Term Memory ◽

Use Of Knowledge

AbstractRapid serial visual presentation (RSVP) of words or pictured scenes provides evidence for a large-capacity conceptual short-term memory (CSTM) that momentarily provides rich associated material from long-term memory, permitting rapid chunking (Potter 1993; 2009; 2012). In perception of scenes as well as language comprehension, we make use of knowledge that briefly exceeds the supposed limits of working memory.

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Ultrastructural Changes of Canine Kidneys During 24-Hour Perfusion on a LI-400 Preservation System

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100065626 ◽

1971 ◽

Vol 29 ◽

pp. 316-317

Author(s):

M. O. Magnusson ◽

D. G. Osborne ◽

T. Shimoji ◽

W. S. Kiser ◽

W. A. Hawk

Keyword(s):

Electron Microscopy ◽

Electrolyte Solution ◽

Ultrastructural Changes ◽

Midline Incision ◽

Short Term ◽

Pentobarbital Anesthesia ◽

Pulsatile Perfusion

Short term experimental and clinical preservation of kidneys is presently best accomplished by hypothermic continuous pulsatile perfusion with cryoprecipitated and millipore filtered plasma. This study was undertaken to observe ultrastructural changes occurring during 24-hour preservation using the above mentioned method.A kidney was removed through a midline incision from healthy mongrel dogs under pentobarbital anesthesia. The kidneys were flushed immediately after removal with chilled electrolyte solution and placed on a LI-400 preservation system and perfused at 8-10°C. Serial kidney biopsies were obtained at 0-½-1-2-4-8-16 and 24 hours of preservation. All biopsies were prepared for electron microscopy. At the end of the preservation period the kidneys were autografted.

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Polychlorinated biphenyl induced hepatocyte alterations

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010012789x ◽

1987 ◽

Vol 45 ◽

pp. 716-717

Author(s):

D.N. Collins ◽

J.N. Turner ◽

K.O. Brosch ◽

R.F. Seegal

Keyword(s):

Lipid Droplets ◽

Wistar Rats ◽

Homovanillic Acid ◽

Polychlorinated Biphenyl ◽

Corn Oil ◽

Environmental Pollutants ◽

Short Term ◽

Pcb Congeners ◽

Urinary Levels ◽

The Brain

Polychlorinated biphenyls (PCBs) are a ubiquitous class of environmental pollutants with toxic and hepatocellular effects, including accumulation of fat, proliferated smooth endoplasmic recticulum (SER), and concentric membrane arrays (CMAs) (1-3). The CMAs appear to be a membrane storage and degeneration organelle composed of a large number of concentric membrane layers usually surrounding one or more lipid droplets often with internalized membrane fragments (3). The present study documents liver alteration after a short term single dose exposure to PCBs with high chlorine content, and correlates them with reported animal weights and central nervous system (CNS) measures. In the brain PCB congeners were concentrated in particular regions (4) while catecholamine concentrations were decreased (4-6). Urinary levels of homovanillic acid a dopamine metabolite were evaluated (7).Wistar rats were gavaged with corn oil (6 controls), or with a 1:1 mixture of Aroclor 1254 and 1260 in corn oil at 500 or 1000 mg total PCB/kg (6 at each level).

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Acetaminophen: Macula densa hypersecretory activity by induced hepatotoxicity

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010012895x ◽

1987 ◽

Vol 45 ◽

pp. 934-935

Author(s):

S.S. Poolsawat ◽

C.A. Huerta ◽

S.TY. Lae ◽

G.A. Miranda

Keyword(s):

Cell Proliferation ◽

Liver Function ◽

Chronic Inflammation ◽

Foam Cell ◽

Term Effect ◽

Short Term ◽

Drug Induced ◽

Experimental Induction ◽

Tissue Alterations ◽

Toxic Responses

Introduction. Experimental induction of altered histology by chemical toxins is of particular importance if its outcome resembles histopathological phenomena. Hepatotoxic drugs and chemicals are agents that can be converted by the liver into various metabolites which consequently evoke toxic responses. Very often, these drugs are intentionally administered to resolve an illness unrelated to liver function. Because of hepatic detoxification, the resulting metabolites are suggested to be integrated into the macromolecular processes of liver function and cause an array of cellular and tissue alterations, such as increased cytoplasmic lysis, centrilobular and localized necroses, chronic inflammation and “foam cell” proliferation of the hepatic sinusoids (1-4).Most experimentally drug-induced toxicity studies have concentrated primarily on the hepatic response, frequently overlooking other physiological phenomena which are directly related to liver function. Categorically, many studies have been short-term effect investigations which seldom have followed up the complications to other tissues and organs when the liver has failed to function normally.

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