Degree Of Negative Correlation Research Articles

Spatial distribution characteristics and influencing factors of traditional villages in Fujian Province, China

As the historical and contemporary values of Chinese traditional villages continue to emerge and the circumstances of the times change, their preservation has a lasting and far-reaching significance in promoting the revitalisation and sustainable development of China’s countryside. However, rapid urbanization began after China’s reform and opening up, and continuous urban expansion led to the rapid decline or even disappearance of these villages. Previous studies on village protection tend to focus on morphological studies from the perspective of individual units, and rarely discuss the influencing factors of spatial distribution. Therefore, there are certain deficiencies in revealing the distribution rules, which makes it difficult to fully carry out the protection work. The article reconstructs the traditional village system of Fujian Province, whose traditional villages cover both national and provincial historical and cultural villages and national and provincial traditional villages. The spatial distribution characteristics and influencing factors of traditional villages in Fujian Province were studied using 1,606 traditional villages of various levels as research objects. The results of the study show that: (1) the spatial distribution of traditional villages in Fujian Province is cohesive, with significant uneven distribution, and there are three high-density agglomerations and two sub-density agglomerations; (2) The spatial distribution shows a pattern of “large scattering, small concentration, more in mountainous areas and less in coastal areas”; (3) Topography, river systems, transportation and socio-economic conditions combine to influence the spatial distribution of traditional villages in Fujian Province, but the degree of influence varies. Physical and geographical conditions play a leading role in the distribution of traditional villages, and road traffic conditions and socio-economic conditions have a secondary impact on the distribution of traditional villages. There is an obvious agglomeration of traditional villages in the mountainous river areas, while there is a certain degree of negative correlation between road traffic conditions and socio-economic conditions and the number of traditional villages. (4) With the support of good policies and economic conditions, the protection and continuation of traditional villages can be promoted to a certain extent, and it is also conducive to the spread of local multicultural culture. Finally, corresponding policy recommendations are made for the conservation and sustainable development of traditional villages in Fujian Province.

Evaluating the effects of different pollution reduction scenarios on the total phosphorus concentration of a mountainous river basin in southwest China using SWAT model: a case study of the Donghe River in Baoshan, Yunnan

Abstract Water quality has become a significant concern in many river basins in China due to both point and non-point source pollution. The SWAT model assessed pollution reduction scenarios and their effects on Donghe River basin water quality in southwest China. The calibrated model evaluated existing point and non-point emissions. Three schemes reduced point sources by 30, 60, and 90% and non-point sources by 25, 50, and 75%, respectively. Simulations analyzed annual and monthly total phosphorus (TP) concentrations under the scenarios. Results showed that the scenarios effectively improved water quality, meeting Class IV TP standards annually. However, TP exceeded standards in dry months (January–April, December) under all scenarios. A certain degree of negative correlation (R = −0.52, P = 0.11) between TP and rainfall suggests rainfall that influences TP. Comprehensive measures are needed to achieve standards year-round. In summary, the study found that reducing emissions improved Donghe water quality overall but more work is required to meet standards during dry periods. Rainfall correlates with and may affect TP. The work emphasizes implementing comprehensive approaches for year-round water quality improvements in the basin.

Shipping Market Valuation and BDI Analysis under COVID-19

Contemporarily, COVID-19 as a major "Black swan" event strong affected the trade and shipping industry. Meanwhile, its continuous spread in the global scope has impacted the international shipping market, and the market value of some domestic shipping companies has also shown a downward trend. This paper adopts dual-line parallel research based on ROE DuPont analysis, CAPM and DDM model to analyze the market value of some shipping companies, and using Eviews regression model to analyze the Baltic Dry Index (BDI). According to analysis, COVID-19 has had a certain negative impact on the valuation of shipping companies. Due to the changes of the epidemic situation, the market valuation of shipping companies is still full of uncertain factors. Moreover, there is a certain degree of negative correlation between COVID-19 and BDI index, which will diminish with the improvement of the epidemic situation. The change of COVID-19 situation has become one of the important factors to judge the trend of BDI index. These results shed light on guiding further exploration of the future market valuation of shipping companies and the judgment of BDI index to some extent.

Non-Dominant Genetic Algorithm for Multi-Objective Optimization Design of Unmanned Aerial Vehicle Shell Process.

This paper uses Pareto-optimized frames and injection molding process parameters to optimize the quality of UAV housing parts with multi-objective optimization. Process parameters, such as melt temperature, filling time, pressure, and pressure time, were studied as model variables. The quality of a plastic part is determined by two defect parameters, warpage value and mold index, which require minimal defect parameters. This paper proposes a three-stage optimization system. In the first stage, the main node position of the electronic chip in the module is collected by the unified sampling method, and the chip calculation index of these node positions is analyzed by the mold flow analysis software. In the second stage, the kriging function predicts the mathematical relationship between the mold index and warpage value and the process parameters, such as melt temperature, filling time, packing pressure, and packing time. In the third stage, using LHD sampling and non-dominant rank genetic algorithm II, a convergence curve of warp value is found near the Pareto optimal frontier. In the fourth stage, the fitting degree of Pareto optimal leading edge curve points was verified by analytical experiments. According to experimental verification, it can be seen that the injection molding factors are pressure and pressure time, because the injection molding time and pressure time are completely positively correlated with the mold indicators, the correlation is the strongest, the mold temperature and glue temperature are not the main influencing factors, and the mold temperature shows a certain degree of negative correlation. In this experiment, the die index is mainly improved by injection time and pressure, optimal injection parameter factor combination and minimum injection index, the optimization rate of the die index is up to 96.2% through genetic algorithm optimization nodes and experimental verification, the average optimization rate of the four main optimization nodes is 91.2%, and the error rate with the actual situation is only 8.48%, which is in line with the needs of actual production, and the improvement of the UAV IME membrane is realized.

Abstract 1488: The role of epithelial miR-149 in immune modulation and progression of bronchial premalignant lesions

Abstract The molecular events involved in the development of bronchial premalignant lesions (PMLs), and their progression to lung squamous cell carcinoma, are not well understood. Prior work characterized lung PML molecular subtypes by identifying co-expressed gene modules associated with histologic severity and progression/persistence. The proliferative subtype was enriched for PMLs with dysplasia. Genes related to interferon signaling and antigen processing/presentation (Module 9) were decreased in progressive/persistent lesions within this subtype, suggesting early immune suppression is related to PML progression. However, the mechanisms that drive these alterations are unclear. We investigated the role of microRNAs (miRNAs) in regulating gene expression associated with PML outcomes. mRNA and miRNA were extracted and sequenced from longitudinally collected endobronchial biopsies from patients with PMLs (148 samples, 30 patients). miRNAs targeting each gene co-expression module were identified based on target gene enrichment and the degree of negative correlation between the miRNA expression and its targets. Expression association with outcome within the proliferative subtype was tested with a mixed effects model adjusting for batch and patient as random effect. Cell type specificity of miRNA expression was tested based on cell type specific sequencing data from FANTOM5 and cell type marker correlation analysis. Genes regulated by NLRC5 were identified with ChIPseq data from Ludigs et al. Target gene suppression was confirmed by transfecting SW900 cells with miR-149-5p. miR-149-5p level in PML biopsies was examined by miRNA in situ hybridization (miR-ISH). miR-149-5p is identified as potential regulator of Module 9 gene expression and is significantly up-regulated in progressive/persistent PMLs. Its expression is highly enriched in epithelial cells in FANTOM5 and positively correlates with basal cell markers within PMLs. Predicted targets of miR-149-5p are down-regulated in the progressive PMLs in both our and data from Merrick et al. MHC-I and related gene expressions are down-regulated in progressing/persistent PMLs. These genes are regulated by the transcriptional coactivator NLRC5 which is a predicted target gene of miR-149-5p. We find that overexpressing miR-149-5p in SW900 cells decreases the expression levels of both NLRC5 and NLRC5 regulated genes. Additionally, miR-ISH targeting miR-149-5p in proliferative biopsy samples confirm its expression in epithelium compartment and association with outcome. Our data suggest epithelial miR-149-5p might be a key regulator of gene expression contributing to PML progression. We hypothesize that by suppressing NLRC5, miR-149-5p inhibits MHC-I gene expression of epithelial cells, promoting early immune depletion and lesion progression. miR-149-5p might therefore be a therapeutic target for preventing PML progression. Citation Format: Boting Ning, Roxana M. Pfefferkorn, Gang Liu, Sherry Zhang, Hanqiao Liu, Christopher Stevenson, Sarah A. Mazzilli, Avrum E. Spira, Marc E. Lenburg, Jennifer E. Beane. The role of epithelial miR-149 in immune modulation and progression of bronchial premalignant lesions [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1488.

Linear fractional differential equations in bank resource allocation and financial risk management model

Abstract The advantage of the linear fractional differential equation for bank resource allocation and financial risk management is that it can test random fluctuations in different functional forms. Given this paper is modelling the asset allocation risk model for rural commercial banks, the linear fractional differential equation analysis method is used to make policy recommendations. The research results of this paper show that credit risk is significantly negatively correlated with the bank's resource allocation. The degree of negative correlation between different levels of credit risk and bank resource allocation is different. Appropriate liquidity risk can optimise the bank's resource allocation.

Research on the “No-Typhoon July” in 2020 and Typhoon Frequency Variations in July in Recent 70 Years

By using China National Climate Center’s 74 circulation characteristics, DERF2.0, BCC-CSM models and Wenzhou Typhoon Network data, and using linear regression, correlation coefficients and other research methods, the variations about typhoon frequency in July from 1951 to 2020 and the large-scale circulation system in July 2020 are analyzed. The results show that 1) in the recent 70 years, the frequency of typhoon generation has slowly decreased, while the frequency of landing typhoons in China has slowly increased; 2) typhoon frequency has varying degrees of negative correlation with the intensity of subtropical high in different regions of the northern hemisphere, especially with the area index and intensity index of the South China Sea subtropical high; 3) in July 2020, the area and intensity of the subtropical high in the Northwest Pacific were abnormally large and strong. Easterly winds prevailed in the tropics, and the cross-equatorial airflow was weak, resulting in a severe reduction in the frequency of typhoon generation, leading to “no-typhoon” events.

Effect of NO2 on O3 Using Complex Network Topology Analysis

In order to study the variation law of the influence degree of air quality factors under time series, this article selects the hourly concentration values of NO2 and O3 from November 2017 to October 2018 in Lanzhou city as the research object, and based on the coarse granulation method, NO2 and O3. The correlation value of hourly concentration value is transformed into the influence degree symbol, and the sequence of effect degree variation under time series is obtained. The network model is constructed by using complex network theory to analyze the time series of NO2 and O3 influence degree series, and the differences and changes in network topology characteristics in overall and different season effect degree symbols of Lanzhou are analyzed. The results show the following. First, from the network analysis, the number of negative correlations of NO2 to O3 is far greater than that of positive correlation and basic noncorrelation effect degree, indicating that NO2 and O3 are negatively correlated. From the factor of season, the law of negative correlation is summer > autumn > spring > winter, indicating that light and temperature are the main factors for the conversion of NO2 to O3. Second, through the analysis of Lanzhou’s overall and seasonal related network topological features, such as node degree distribution, node intensity distribution, and network betweenness, the change sequence consisting of the influence degree symbols h, H, and m plays an important role in each network. The sequence of changes consisting of M, H, and S has the lowest effect in each network, indicating that in the day of the time series, the conversion of NO2 to O3 in Lanzhou is mainly dominated by different degrees of negative correlation. Third, through the analysis of network cluster degree, it is found that most of the changes in the degree of change have a transformation and a high degree of transformation, indicating that the effect of NO2 on O3 in the original sequence is less stable. Fourth, through the network average shortest path and diameter analysis, it is found that the conversion between the changes in the degree of influence requires at least one day and at most three days. That is to say, the influence of NO2 on O3 can be maintained for up to three days. From the network, the complexity of the influence of NO2 on O3 in the original sequence of four seasons was founded.

An Updated Strategy for Designing Non-Fullerene Acceptors by the Lowest Singlet and Triplet States Excitation: Influence of Periodical Substitution from O, S, and Se to Te for BAE Derivatives

When one is trying to maintain original advantageous properties of molecule without increasing the difficulty of synthesis and processing, simultaneously, adding more predictable properties is a preferred choice for designing promising molecules. Here, we report the photovoltaic performance of bistricyclic aromatic enes (BAE) derivative acceptors as a function of heteroatom substitutions (O, S, Se, Te), and the range they can maintain. Beyond that, by combining singlet–triplet exciton conversion with singlet fission (SF), an additional perspective to characterize molecules performance is predicted by employing T1-excitation. Theoretical calculation results showed that for small molecules (BAEs), heavy atom substitution of the same group could increase conformation stability, electron acceptability, and spin–orbit coupling. After expansion of the molecular size (DPP-BAE-DPP), the difference in molecular properties is mainly due to the conformation type for singlet states excitation. For triplet states excitation, the degree of negative correlation between SF and singlet–triplet exciton conversion decreases, which is conducive to obtaining more T1 excitons, thus improving the organic photovoltaic performances. As a result, A-S-DPP, A-Te-DPP, T-S-DPP, T-Se-DPP and T-Te-DPP not only have superior single-excitation performance but also potential triple-excitation possibilities; they are promising acceptors. These results provided some new evidence for designing nonfullerene acceptors and demonstrating the role of heavy atoms substitution in photovoltaic performance.

Neural correlates of dynamic changes in working memory performance during one night of sleep deprivation.

Total sleep deprivation (TSD) is common in modern society leading to deterioration of multiple aspects of cognition. Dynamic interaction effect of circadian rhythmicity and homeostatic sleep pressure on sustained attention have been intensively investigated, while how this effect was represented on performance and cerebral responses to working memory, another important element of many neurobehavioral tasks, was not well elucidated. Thirty-six healthy subjects with intermediate chronotype performed the Sternberg working-memory task (SWMT) while undergoing functional magnetic resonance imaging every 2 hr from 10:00 p.m. on the first day to 6:00 a.m. on the second day. Using data from three imaging sessions (10:00 p.m., 04:00 a.m., and 06:00 a.m.), we found that the slowest SWMT reaction time and weakest cerebral responses were not at the end of TSD (06:00 a.m.) but during the early morning (04:00 a.m.) hours of the TSD. In addition, during this worst period of TSD, reaction time for the SWMT were found to be negatively correlated with task-related activation in the angular gyrus and positively correlated with the degree of negative correlation between the control and default networks. Our results revealed a rebound of SWMT reaction time and cerebral responses after the mid-time point of regular biological sleep night and provided more evidence that different cognitive tasks are differentially affected by sleep loss and circadian rhythmicity.

Human PBMCs fight or flight response to starvation stress: Increased T-reg, FOXP3, and TGF-β1 with decreased miR-21 and Constant miR-181c levels.

Regulatory T-lymphocytes play a prominent role in autoimmunity, allergy, and cancer. In some conditions such as inflammation and tumor, immune cells are encountered with metabolic stress. Emerging evidence indicates the contribution of microRNAs in both metabolism and immune regulation. Herewith, we have examined the in vitro effects of serum starvation for 16, 48, 72 and 96 h on the expression of T-reg differentiation markers (CD4, CD25, CD127, and FOXP3) as well as on the Transforming Growth Factor-β1 (TGF-β1) and some microRNAs (miR-21,-29a,-31,146a,-155,-181a and -181c) levels in human Peripheral Blood Mononuclear Cells (PBMCs). The percentage of CD4+CD25+CD127low/-FOXP3+ T-regs, as well as FOXP3 expression, was increased in starved lymphocytes (p < 0.01). 96 h-starved PBMCs had the lowest T-eff/T-reg ratio (p < 0.05). All the studied miRNAs except miR-181c were significantly down-regulated in those cells (p < 0.05), in particular, miR-29a and miR-155 were sharply declined in 48h-starved PBMCs (p < 0.01). There was a negative correlation between time of starvation and microRNAs expression, except for miR-181c (r-value = -0. 61 to -0.9 and p-value = 0.037 to 0). The percentage of T-reg was inversely correlated with all miRNAs levels except for miR-31 and miR-181c (r-value = -0.68 to -0.78 and p-value = 0.015 to 0.003). FOXP3 expression exhibited a same degree of negative correlation with miR-31 and miR-155 expression levels (r = -0.57 and p = 0.05, for both). Increasing starvation duration led to a rise inTGF-β1 protein levels (p<0.01), especially its active form (P<0.001). This study introduced the serum starvation as a tool for immunoregulation which acts probably through increasing TGF-β1 production and inducing some alterations in microRNAs expression.

Study on the status of fear of cancer recurrence and its correlation with quality of life in patients with bladder cancer

Objective To investigate the current status of fear of cancer recurrence in bladder cancer patients, and to explore the correlation between fear of recurrence and quality of life. Methods A total of 96 bladder cancer patients were recruited by convenience sampling method from April 2017 to July 2017. They were investigated through general information questionnaire, Chinese version of Fear of Progression Questionnaire Short Form and Functional Assessment of Cancer Therapy-Bladder cancer form respectively. Results The total score of fears of recurrence was 28.76±10.33, the total score of quality of life was 123.66±20.63. A total of 28 patients had a dysfunctional level of fears of recurrence (total score ≥34), the incidence was 29.2% (28/96). There were significant differences in the total scores of fears of recurrence at different ages, fears of recurrence were not related to another sociodemographic factors (gender, educational attainment and income) or disease, treatment related factors. The total scores of fears of recurrence and the total score of quality of life showed a high degree of negative correlation (r=-0.726, P < 0.01), the quality of life in physical, social and family, emotional, functional well being were negatively correlated with fears of recurrence (r=-0.841--0.592, P < 0.01). Conclusions Bladder cancer patients have a higher incidence of fears of recurrence and had an impact on quality of life from the physical, psychological and social domains, nurses should perceive the fears of recurrence of patients as soon as possible and give corresponding intervention measures to improve the quality of life of bladder cancer patients. Key words: Urinary bladder neoplasms; Recurrence; Fear; Quality of life

Dynamic Relationship between Macroeconomic Determinants and Corporate Bonds Performance: The Case of India

Corporate bonds can serve as an important alternative to the more expensive sources of financing and the market requires more exploration for its development. For ensuring the steady growth in this sector, the government can adopt several macroeconomic policy measures which can accelerate the market's progress. The study has been undertaken to analyse the relationship between selected macroeconomic variables and Indian corporate bond market performance. The study used multiple linear regression and Granger causality test to analyse the relationship between the variables. The results found no impact of macro-economic variables on corporate bond performance. Further, study found no causality between macro-economic variables on corporate bond performance. Whereas correlation results clearly shows the bond returns has low degree of negative correlation with Nifty returns and GDP growth rate. The study suggests bond market participants to consider stock market performance before tanking investment decisions.

The catalytic effect of honey on formation of reducing sugars during sucrose hydrolysis

In commercial apiculture, beekepers usually remove honey from hives and replenish food reserves with sugar syrup. When honeybees use sugar syrup (sucrose solution), they break down sucrose into glucose and fructose. These processes exhaust and weaken bees. In order to prevent bee exhaustion resulting from this processing, bees should preferably be supplied with ready made food before winter, i.e., with syrup in which sucrose has already been inverted. Feeding with inverted syrups is the most popular way of honeybee feeding. Beekeepers usually prepare inverted syrups by adding a weak organic acid (citric, oxalic, acetic or lactic acid) to sucrose solution at elevated temperatures. Inverted syrup production under uncontrolled pH, temperature and time conditions can cause the formation of 5-hydroxymethyl-2-furaldehyde (HMF), a compound harmful to bees. High quality inverted syrup can be obtained through the hydrolytic decomposition of sucrose by the enzyme invertase. Due to its invertase content, honey can be used as a biocatalyst for sucrose inversion. Invertase activity depends on the type, method and time of honey storage. This study evaluates the catalytic effect of acacia honey on formation of reducing sugars during hydrolysis of 50 wt.% sucrose solution. The ratio of reducing sugars and sucrose at 40?C, after 5 days of hydrolysis at a concentration of honey and 10 wt.% was 0.30 g reducing sugars/g of sucrose. The highest content of reducing sugars was achieved at a temperature of 35?C, after 48 h of invertion. In all samples of hydrolysates obtained at different temperatures (35?65?C), HMF was detected at concentrations of less than 4.32 mg kg?1. A high degree of negative correlation (coefficient of linearity ?0.94) was established between parameters of volumetric and polarimetric measurements during the hydrolysis of sucrose.

Assessment of Used Formulae for Sonographic Estimation of Fetal Weight in Sudanese Population

The objective of this study is to assess commonly used formulae (Sheppard, Campbell, Hadlock I, II, III, and IV) for estimation of fetal weight in Sudanese population. A descriptive cross-sectional study was conducted at Saudi Hospital-Khartoum-Sudan; from December 2015 to April 2016. The study included 225 singleton pregnancies. The fetal biometry—Biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC), femur length (FL) and actual birth weights (ABW) were taken. Statistical analysis showed significant results at p ≤ 0.005. Results showed that the significant highest positive correlation between the ABW and the EFW/Kg was seen in the Hadlock I, III and IV equations having an equal values (0.951) followed by Hadlock II (0.946), Sheppard (0.872) and lastly Campbell (-0.925) with significant high degree of negative correlation. The new established equation EFWFLHCAC is the best formula identified in our study to predict Sudanese babies weight ranged between 1.86 Kg to 3.987 Kg.

Correlation analysis of coping style and critical thinking among nursing undergraduates students

Objective To explore the relation between coping style and critical thinking among nursing students in order to provide the powerful evidence for instructing nursing students to take the correct coping style so as to improve their critical thinking .Methods Sixty-three nursing students in Grade 2010 in School of Nursing, Jilin University were surveyed by critical thinking disposition inventory （ CTDI-CV） and simple coping style questionnaire （SCSQ）.Results The average score of CTDI-CV was （278.35 ±33.14） in the nursing students, and the percent of students with less than 280 was 58.73%, and the percent of students with 280 to 350 was 36.51%, and the percent of students with more than 350 was 4.76%.The score of positive coping styles in the nursing students was （1.86 ±0.626）, and was higher than that of the national norm , and the difference was not statistically significant （t =0.207,P>0.05）.The score of negative coping styles in the nursing students was （1.18 ±0.566）, and was lower than that of the national norm , and the difference was statistically significant （t=-5.745,P 〈0.01）.Nursing undergraduates positive coping style was positively correlated with CTDI-CV scores （ P〈0.05）, negative coping styles and negatively correlated with CTDI-CV scores （P〈0.01）.Negative coping style and the critical mind all dimensions are in different degree of negative correlation, positive coping styles and open mind , systematic ability, self-confidence were positively correlated （P〈0.01）.Conclusions Developing positive coping styles in the nursing students can improve their critical thinking . Key words: Coping style; Critical thinking; Nursing undergraduates student

Spatial distribution of birth defects among children aged 0 to 5 years and its relationship with soil chemical elements in Chongqing

To explore the correlation between the incidence of birth defects and the contents of soil elements so as to provide a scientific basis for screening the related pathogenic factors that inducing birth defects for the development of related preventive and control strategies. MapInfo 7.0 software was used to draw the maps on spatial distribution regarding the incidence rates of birth defects and the contents of 11 chemical elements in soil in the 33 studied areas. Variables on the two maps were superposed for analyzing the spatial correlation. SAS 8.0 software was used to analyze single factor, multi-factors and principal components as well as to comprehensively evaluate the degrees of relevance. Different incidence rates of birth defects showed in the maps of spatial distribution presented certain degrees of negative correlation with anomalies of soil chemical elements, including copper, chrome, iodine, selenium, zinc while positively correlated with the levels of lead. Results from the principal component regression equation indicating that the contents of copper(0.002), arsenic(-0.07), cadmium(0.05), chrome (-0.001), zinc (0.001), iodine(-0.03), lead (0.08), fluorine(-0.002)might serve as important factors that related to the prevalence of birth defects. Through the study on spatial distribution, we noticed that the incidence rates of birth defects were related to the contents of copper, chrome, iodine, selenium, zinc, lead in soil while the contents of chrome, iodine and lead might lead to the occurrence of birth defects.

Relationship between variations of severe isthmic spondylolisthesis spino-pelvic parameters and clinical symptoms

To explore the relationship between variations of severe isthmic spondylolisthesis spino-pelvic parameters and clinical symptoms. A retrospective study of spino-pelvic parameters was conducted for 45 patients with L5 severe isthmic spondylolisthesis. Their spino-pelvic parameters were analyzed on preoperative full spinal radiography: grade of spondylolisthesis, pelvic incidence (PI), sacral slope (SS), pelvic tilt (PT), lumbar lordosis (LL), thoracic kyphosis (TK), SFHD, SFVD, SC7D and T9 tilting angle. According to the Oswestry score, the patients with low back pain were divided into light and severe groups. T-tests were used to compare their parameters. The analyses of multiple factor correlation, linear regression and stepwise regression were used to examine the associations between all parameters and Oswestry score. Grade of spondylolisthesis, PT, LL, T9 tilting angle, SFHD, SC7D, PT/SS, SFHD/SFVD, LL/TK were significantly greater and SS, SFVD were significantly smaller for patients with severe low back pain versus light low back pain (P < 0.05). PI or TK had no statistically significant difference between two groups. Multiple factor correlation, linear regression and stepwise regression: Grade of spondylolisthesis, PT, SC7D, LL and SFHD had significant positive correlations with Oswestry score. Degree of positive correlation: Grade of spondylolisthesis > SC7D > PT > LL > SFHD. And PI, TK or T9 tilting angle had no significant correlation with Oswestry score. SS and SFVD had significant negative correlations with Oswestry score. Degree of negative correlation: SS > SFVD. PT/SS, SFHD/SFVD and LL/TK had significant positive correlation with Oswestry score. Degree of positive correlation: PT/SS> SFHD/SFVD > LL/TK. Clinical symptoms of severe isthmic spondylolisthesis have significant positive correlations with grade of spondylolisthesis, PT, SC7D, LL, SFHD, PT/SS, SFHD/SFVD, LL/TK and significant negative correlations with SS and SFVD. Low back pain symptom has no significant correlation with PI, TK or T9 tilting angle.

Oil prices and economic activity in Greece

The paper studies the relationship between oil prices and economic activity in Greece during the period 1982:1–2008:8. Different empirical methods are used to estimate whether oil price changes affect asymmetrically the economic activity. A regime-switching model (RS-R) and a threshold regression modeling (TA-R) are applied which have the advantage to capture the dependence structure of the series both in terms of constant and variance. The empirical evidence suggests that the degree of negative correlation between oil prices and economic activity strengths during periods of rapid oil price changes and high oil price change volatility.

Poster #31 FUNCTIONAL CONNECTIVITY IN RELATION TO DIFFERENT GENETIC RISK LEVELS FOR PSYCHOTIC DISORDER: A RESTING STATE FMRI STUDY

Brain regions simultaneously activated during any cognitive process are functionally connected, forming large-scale networks. These functional networks can be examined during active conditions [i.e., task-functional magnetic resonance imaging (fMRI)] and also in passive states (resting-fMRI), where the default mode network (DMN) is the most widely investigated system. The role of the DMN remains unclear, although it is known to be responsible for the shift between resting and focused attention processing. There is also some evidence for its malleability in relation to previous experience. Here we investigated brain connectivity patterns in 16 healthy young subjects by using an n-back task with increasing levels of memory load within the fMRI context. Prior to this working memory (WM) task, participants were trained outside fMRI with a shortened test version. Immediately after, they underwent a resting-state fMRI acquisition followed by the full fMRI n-back test. We observed that the degree of intrinsic correlation within DMN and WM networks was maximal during the most demanding n-back condition (3-back). Furthermore, individuals showing a stronger negative correlation between the two networks under both conditions exhibited better behavioural performance. Interestingly, and despite the fact that we considered eight different resting-state fMRI networks previously identified in humans, only the connectivity within the posteromedial parts of the DMN (precuneus) prior to the fMRI n-back task predicted WM execution. Our results using a data-driven probabilistic approach for fMRI analysis provide the first evidence of a direct relationship between behavioural performance and the degree of negative correlation between the DMN and WM networks. They further suggest that in the context of expectancy for an imminent cognitive challenge, higher resting-state activity in the posteromedial parietal cortex may be related to increased attentional preparatory resources.