A factor approach to realized volatility forecasting in the presence of finite jumps and cross-sectional correlation in pricing errors

There is a growing literature on the realized volatility (View the MathML source) forecasting of asset returns using high-frequency data. We explore the possibility of forecasting View the MathML source with factor analysis; once considering the significant jumps. A real high-frequency financial data application suggests that the factor based approach is of significant potential interest and novelty

Uranium Production as a Byproduct from Yarimca Phosphoric Acid Plan(Turkey)

This paper deals with uranium production from the phos-phoric acid products of Yarunca Fertilizer Plant. After examination of the phosphate rocks consumed in this plant and the acid products, solvent extraction tests were conducted to determine the effects of acid concentration, solvent concentration in kerosene, contact time and acid /solvent ratio on the recoveries of uranium. 98 % of total uranium in acid was recovered in the organic phase by applying 5 stage extraction. Following the extraction tests, acidic and basic stripping were applied to organic phase and uranium was precipitated as yellow cake from the stripping solutions. In the stripping tests mainly aqueous /organic phase ratio and stripping time were investigated using HCI and Na, CO3 as stripping agents. Na, CO3 provided higher uranium recoveries both at the short time and low ratio of the stripping solution. Yellow cakes were produced containing 13-18.4 %U308 from acidic and 30-46.4 % U308 from basic stripping solutions

Determination of Flower Characteristics of Some Kiwifruit Genotypes (Actinidia Spp.) Obtained with Breeding Program

All Actinidia species are dioecious, male and female flowers grow on separate kiwifruit plants. In breeding studies, it is generally desirable to obtain female individuals. However, male plants are also of great importance for pollination. Therefore, it is necessary to examine the flower characteristics of the genotypes obtained by breeding studies. This research was conducted in the kiwifruit breeding plot of Yalova Atatürk Horticultural Central Research Institute for two years. Genotypes obtained from cultivars belonging to Actinidia deliciosa and Actinidia chinensis were used in the research. At the time of flowering, phenological observations of male and female genotypes, which are prominent in the population, have been made and the developmental stages of the flowers have been determined. At least 10 flowers of each genotype were used to determine the morphological characteristics.Number of leaves, number of petals, number of male organs, number of filaments, number of female organs, number of female organs and number of stylus were examined in order to determine flower characteristics. When the data obtained as a result of two years are evaluated; significant differences have been obtained particularly in terms of flowering time, flowering period, the number of stylus, the filament size, the number of female organs and the number of male organs. Female cultivars/genotypes tend to flowering later than male cultivars/genotypes, and female cultivars/genotypes have shorter filament length than male cultivars/genotypes. It has also been clearly observed that ovaries are not functional in male types

An efficient parallelization technique for high throughput FFT-ASIPs

Fast Fourier Transformation (FFT) and it's inverse (IFFT) are used in Orthogonal Frequency Division Multiplexing (OFDM) systems for data (de)modulation. The transformations are the kernel tasks in an OFDM implementation, and are the most processing-intensive ones. Recent trends in the electronic consumer market require OFDM implementations to be flexible, making a trade-off between area, energy-efficiency, flexibility and timing a necessity. This has spurred the development of Application-Specific Instruction-Set Processors (ASIPs) for FFT processing. Parallelization is an architectural parameter that significantly influence design goals. This paper presents an analysis of the efficiency of parallelization techniques for an FFT-ASIP. It is shown that existing techniques are inefficient for high throughput applications such as Ultra Wideband (UWB), because of memory bottlenecks. Therefore, an interleaved execution technique which exploits temporal parallelism is proposed. With this technique, it is possible to meet the throughput requirement of UWB (409.6 Msamples/s) with only 4 non-trivial butterfly units for an ASIP that runs at 400MHz. © 2006 IEEE

Presence of factors that activate platelet aggregation in mitral stenotic patients' plasma

BACKGROUND: Although the association between mitral stenosis (MS) and increased coagulation activity is well recognized, it is unclear whether enhanced coagulation remains localized in the left atrium or whether this represents a systemic problem. To assess systemic coagulation parameters and changes in platelet aggregation, we measured fibrinogen levels and performed in vitro platelet function tests in plasma obtained from mitral stenotic patients' and from healthy control subjects' peripheral venous blood. METHODS: Sixteen newly diagnosed patients with rheumatic MS (Group P) and 16 healthy subjects (Group N) were enrolled in the study. Platelet-equalized plasma samples were evaluated to determine in vitro platelet function, using adenosine diphosphate (ADP), collagen and epinephrine in an automated aggregometer. In vitro platelet function tests in group N were performed twice, with and without plasma obtained from group P. RESULTS: There were no significant differences between the groups with respect to demographic variables. Peripheral venous fibrinogen levels in Group P were not significantly different from those in Group N. Adenosine diphosphate, epinephrine and collagen-induced platelet aggregation ratios were significantly higher in Group P than in Group N. When plasma obtained from Group P was added to Group N subjects' platelets, ADP and collagen-induced, but not epinephrine-induced, aggregation ratios were significantly increased compared to baseline levels in Group N. CONCLUSION: Platelet aggregation is increased in patients with MS, while fibrinogen levels remain similar to controls. We conclude that mitral stenotic patients exhibit increased systemic coagulation activity and that plasma extracted from these patients may contain some transferable factors that activate platelet aggregation

The Mediterranean Island Wetlands (MedIsWet) inventory: strengths and shortfalls of the currently available floristic data

MedIsWet (Conservation of the island wetlands of the Mediterranean Basin) is a MAVA funded project which aims at investigating all seasonal or permanent island wetlands both natural and artificial, with a minimum extent of 0.1 hectares. More than 16,000 wetlands from almost all the Mediterranean, including islands from France, Italy, Malta, Croatia, Cyprus, Tunisia, Turkey, Greece and Spain were mapped. Over 2,500 of them were inventoried in the field and more than 500 scientific contributions catalogued. In total, more than 35,000 plant occurrences were uploaded, in a standardised and comparable way, on the national open-source web portals. These can be related to the recorded threats, uses and other spatially retrievable information. Here, we show strengths and shortfalls of the already available information about the floristic records. Although further improvements are needed, we discuss how these data can be used for research and policy actions and to develop conservation projects

Single left coronary artery with separate origins of proximal and distal right coronary arteries from left anterior descending and circumflex arteries – a previously undescribed coronary circulation

A single left coronary artery with right coronary artery arising from either left main stem (LMS) or left anterior descending artery (LAD) or circumflex artery (Cx) is an extremely rare coronary anomaly. This is the first report of separate origins of proximal and distal RCA from LAD and circumflex arteries respectively in a patient with a single left coronary artery. This 57 year old patient presented with unstable angina and severe stenotic disease of LAD and Cx arteries and underwent urgent successful quadruple coronary artery bypass grafting. The anomalies of right coronary artery in terms of their origin, number and distribution are reviewed

Risk Factors Associated with Adverse Fetal Outcomes in Pregnancies Affected by Coronavirus Disease 2019 (COVID-19): A Secondary Analysis of the WAPM study on COVID-19

To evaluate the strength of association between maternal and pregnancy characteristics and the risk of adverse perinatal outcomes in pregnancies with laboratory confirmed COVID-19. Secondary analysis of a multinational, cohort study on all consecutive pregnant women with laboratory-confirmed COVID-19 from February 1, 2020 to April 30, 2020 from 73 centers from 22 different countries. A confirmed case of COVID-19 was defined as a positive result on real-time reverse-transcriptase-polymerase-chain-reaction (RT-PCR) assay of nasal and pharyngeal swab specimens. The primary outcome was a composite adverse fetal outcome, defined as the presence of either abortion (pregnancy loss before 22 weeks of gestations), stillbirth (intrauterine fetal death after 22 weeks of gestation), neonatal death (death of a live-born infant within the first 28 days of life), and perinatal death (either stillbirth or neonatal death). Logistic regression analysis was performed to evaluate parameters independently associated with the primary outcome. Logistic regression was reported as odds ratio (OR) with 95% confidence interval (CI). Mean gestational age at diagnosis was 30.6\ub19.5 weeks, with 8.0% of women being diagnosed in the first, 22.2% in the second and 69.8% in the third trimester of pregnancy. There were six miscarriage (2.3%), six intrauterine device (IUD) (2.3) and 5 (2.0%) neonatal deaths, with an overall rate of perinatal death of 4.2% (11/265), thus resulting into 17 cases experiencing and 226 not experiencing composite adverse fetal outcome. Neither stillbirths nor neonatal deaths had congenital anomalies found at antenatal or postnatal evaluation. Furthermore, none of the cases experiencing IUD had signs of impending demise at arterial or venous Doppler. Neonatal deaths were all considered as prematurity-related adverse events. Of the 250 live-born neonates, one (0.4%) was found positive at RT-PCR pharyngeal swabs performed after delivery. The mother was tested positive during the third trimester of pregnancy. The newborn was asymptomatic and had negative RT-PCR test after 14 days of life. At logistic regression analysis, gestational age at diagnosis (OR: 0.85, 95% CI 0.8-0.9 per week increase; p<0.001), birthweight (OR: 1.17, 95% CI 1.09-1.12.7 per 100 g decrease; p=0.012) and maternal ventilatory support, including either need for oxygen or CPAP (OR: 4.12, 95% CI 2.3-7.9; p=0.001) were independently associated with composite adverse fetal outcome. Early gestational age at infection, maternal ventilatory supports and low birthweight are the main determinants of adverse perinatal outcomes in fetuses with maternal COVID-19 infection. Conversely, the risk of vertical transmission seems negligible

Response of seeds and pollen of Onobrychis viciifolia and Onobrychis oxyodonta var. armena to NaCl stress

Sainfoin (Onobrychis viciifolia Scop.) is an important forage legume crop with 52 species adapted to dry and poor soils in Turkey, but little is known about the effects of salinity on germination and seedling growth in arid and semiarid regions suffering from salinity problem. The seeds and pollen of two species of sainfoin O. viciifolia and O. oxyodonta var. armena (Syn: O. armena) were exposed to 0, 5, 10, 20 and 30 dS m-1 of NaCl under in vivo and in vitro conditions and evaluated for germination under salt stress by comparing germination percentage, mean germination time, root and shoot length, fresh and dry seedling weight and dry matter. Increased salinity levels generally resulted in decrease in all traits except time to germination, dry seedling weight and dry matter, which increased at high salinity levels. O. viciifolia seeds germinated and grew more rapidly compared to O. armena seeds under NaCl stress. No decrease in germination and seedling growth up to 10 dS m-1 was recorded. On the other hand, there was a clear difference for germination and seedling growth between in vivo and in vitro conditions. Lower values were obtained from in vitro experiments; suggesting that mineral salts, sucrose and agar may have resulted in higher osmotic potential inhibiting germination and seedling growth of species compared in vivo conditions. Decrease in pollen germination with increasing salinities was very sharp, indicating that pollen germination had higher sensitive to salinity. But, pollen grains of O. armena germinated rapidly compared to O. viciifolia. The results emphasize that in vivo experiments could be used for screening of NaCl tolerance in sainfoin cultivars without expensive chemicals and sophisticated equipments, but pollen germination is more appropriate for its wild relatives