Miracle-dz/UniFAR-FTUs huggingface dataset:
Portfolio trading

STOCK INDEX FUTURES bond market, and they will sell stock portfolios and buy bonds when they believe the opposite. Investors specializing in stock selection buy individual stocks and short-sell the market to hedge against general stock market risk. Unfortunately, procedures for selling short an actual portfolio of common stocks are extremely cumbersome and expensive. Upstairs brokerage firms have responded to the demand for portfolio trading by offering to bid on portfolios of stocks that are to be sold or bought. Such bids are usually relative bids that is, they guarantee a price relative to a future market price. For example, a broker may guarantee to buy a portfolio at a price no less than the price calculated on the basis of the closing prices of each of the stocks in the portfolio. At the time of the bid, agreement is also reached on the commission to be charged. 1 If the broker is able to dispose of the stocks at prices better than the bid price, profits are frequently shared. Bids on portfolios of stocks may be disclosed or may be blind. In a disclosed bid, the selling institution discloses the identity of the individual stocks in the portfolio. A disclosed bid can be dangerous to the selling institution, however. For example, if the price of the transaction will be the dosing price of the stocks later in the day, the upstai.rs broker has an incentive to allow those closing prices to be lower by making sure that the closing prices are at the bid side of the market rather than the ask si.de of the market. The stocks acquired by the broker can then be sold on the following day at higher prices. Blind bids overcome this problem, because the selling institution does not disclose the names of the individual stocks in the portfolio. Instead it provides a general description of the portfolio and gives assurances that it is broadly diversified. MEANING AND BENEFITS OF PORTFOLIO TRADING earn trading and portfolio trading have been the focus of an unusual amount of attention since the events of October 1987 and in the investigations that followed those events. Yet, we cannot make the right decisions about what to do or what not to do -about these strategies without a more complete understanding of why they have grown, what they can accomplish, and how they fit into an asset market system. The goal of this paper is to explain these developments and to argue for the benefits to investors that these strategies can provide.
Ecological Traits Predicting Amphibian Population Declines in Central America

Abstract: Amphibian populations are declining on all continents on which they occur, but not all species have been affected equally. Populations of some species are extirpated, others have declined but survive, some have not obviously declined, and some are increasing. If amphibian populations at multiple sites were affected by the same factors, then surviving species should share traits that promote persistence, whereas declining species should share traits that promote susceptibility. Identifying these traits can help diagnose potential causes and thus help to direct conservation actions. Using logistic regression, we quantified the vulnerability of amphibian populations in four areas in Central America. We analyzed a species‐specific database of taxonomic identity, geographic and elevational range, elevational distribution, adult and larval habitat, activity period, and maximum adult body size. We found that ( 1 ) all four sites exhibited the same pattern of decline ( there were no interactions between site and other variables ); ( 2 ) declining populations shared aquatic habitats, restricted elevational ranges, and large body sizes; and ( 3 ) there was an interaction between body size and elevational range. The most significant variable in the model was lifetime aquatic index, a factor unrelated to demographic vulnerability and one that therefore might indicate the potential causative agent( s ). Our results provide a predictive model with which to assess potential causes of population declines in other areas, and we generated a list of 52 species predicted to decline at a currently unaffected site in central Panama.
Effects of some Systemic Fungicides on the Chiasma Frequencies in Hordeum vulgare

Four systemic fungicides-thiabendazole, fuberidazole, carboxin and oxycarboxin have been tested for effects on chiasmata in barley. All compounds excepting thiabendazole have depressed chiasma frequencies significantly. The source of such a variation could be laid a) fairly very early in development as the treatment was done during the first DNA synthetic period in the seeds or b) much later during development because the compounds are systemic in nature. The observations are likely to be useful in genetic toxicology and in dealing with experimental crop populations.
Zonal Structure of the Shoot Apex in Encephalartos, Bowenia, and Macrozamia

1. The structure of the shoot apex is described for six species of Encephalartos and for one species each of Bowenia and Macrozamia. 2. The shoot apex consists of four zones. The summit is occupied by a zone of initiation from which growth converges to a zone of central mother cells where increase in volume predominates. Growth is divergent from the central mother cell zone. 3. A peripheral zone, which is derived from the central mother cells and superficial layer, flanks the central mother cell zone. Leaf primordia, cortex, and vascular tissue are derived from this zone. 4. The zone of central mother cells is underlaid by a rib meristem which builds up the massive pith.
REVIEW ■ : Multiple Representations of Space in the Brain

Lesions of the posterior parietal cortex have long been known to produce visuospatial deficits in both humans and monkeys. Yet there is no known "map" of space in the parietal cortex. The posterior parietal cortex projects to a number of other areas that are involved in specialized spatial functions. In these areas, space is represented at the level of single neurons and, in many of them, there is a topographically organized map of space. These extraparietal areas include the premotor cortex and the putamen, involved in visuomotor space, the frontal eye fields and the superior colliculus, involved in oculomotor space, the hippocampus, involved in environmental space, and the dorsolateral prefrontal cortex, involved in mnemonic space. In many of these areas, space is represented by means of a coordinate system that is fixed to a particular body part. Thus, the processing of space is not unitary but is divided among several brain areas and several coordinate systems, in addition to those in the posterior parietal cortex. The Neuroscientist 1:43-50, 1995
The herpes simplex virus type 1 particle: structure and molecular functions

This review is a summary of our present knowledge with respect to the structure of the virion of herpes simplex virus type 1. The virion consists of a capsid into which the DNA is packaged, a tegument and an external envelope. The protein compositions of the structures outside the genome are described as well as the functions of individual proteins. Seven capsid proteins are identified, and two of them are mainly present in precursors of mature DNA‐containing capsids. The protein components of the 150 hexamers and 12 pentamers in the icosahedral capsid are known. These capsomers all have a central channel and are connected by Y‐shaped triplexes. In contrast to the capsid, the tegument has a less defined structure in which 11 proteins have been identified so far. Most of them are phosphorylated. Eleven virus‐encoded glycoproteins are present in the envelope, and there may be a few more membrane proteins not yet identified. Functions of these glycoproteins include attachment to and penetration of the cellular membrane. The structural proteins, their functions, coding genes and localizations are listed in table form.
Estimating fat reserves in the brush-tailed possum, Trichosurus vulpecula Kerr (Marsupialia : Phalangeridae)

Two hundred possums were collected from an area in Westland, New Zealand. Their carcasses were macerated and total fat content was determined by chemical means. The reliability of existing indices (visual, kidney fat, back fat, marrow fat) for predicting the proportion of total fat in the body was investigated. Two indices were developed and tested; one based on fat depots in the mesogastrium, the other based on deviations from a standardized weight for length. The index based on weight deviations gives good results if derived from a large sample of animals, and has the advantage that it can be used on live animals under sedation. The marrow fat index gives good results if fat reserves are low, and the mesogastric index does at other times, when estimates are obtained by autopsy of a few animals. Analysis of variance showed that, within the population studied, time of the year and a season-age interaction were the only significant sources of heterogeneity in fat reserves.
Territory Size of Wood Ants (Hymenoptera: Formicidae): A Search for Limits of Existence of Formica polyctena Först., An Inherently Polygynic and Polycalic Species

Abstract. Wood ants are often absent on islands of the Gulf of Finland, even when seemingly suitable habitats are available. Their absence may partially be explained by the lack or rarity of ant species suitable as host during colonisation through temporary parasitism. To search for the limits of living conditions on islands, given colonisation constraints are overcome, we artificially established wood ant colonies on several islands constituting a series from suboptimal to extremely harsh living conditions. The case reported here showed that a barren < 0.2 ha islet, with aphids on its single pine tree the only permanent and relatively rich food source, has allowed the existence of an artificially introduced Formica polyctena Först. colony for 22 years. The ambient living conditions are probably close to the limit for the species, as evidently the colony does not produce sexual offspring. Thus the sustained existence of the colony is dependent on adoption of fertile gynes originating in colonies that live in more optimal conditions. We suggest that the polygynic social mode of the inherently polycalic F. polyctena is the key for its sustained existence on the islet, as polygyny together with receptivity to new, even alien queens keeps the colony alive in a sink habitat insufficient for production of own sexual offspring.
A clonal view of αβ T cell responses

Abstract Quantitative analyses of antigen (Ag)-specific αβ T cell populations have provided a large body of information on the natural course of T cell immune responses. New tools are now available to determine the clonal composition of Ag-specific pools in individual responders, an approach which offers direct insights into the generation of T cell immune responses and establishment of protective immunity. The present review discusses the parameters that determine the composition of Ag-specific T cell responses. Emphasis is placed on the role of the naive αβ T cell repertoire and on the dynamics of individual Ag-specific T cell clones during the successive phases of an immune response.
Available Water in Stems of Some Rocky Mountain Conifers

1. The water content of the terminal twigs, per dry weight of leaf attached above the sectioned twig, was higher in ponderosa pine (Pinus ponderosa) than in any of the other three species studied. There were no significant differences among grand fir (Abies grandis), Douglas fir (Pseudotsuga taxifolia), and red cedar (Thuja plicata) on this basis, although red cedar was usually lowest. Water contents of the twigs as a percentage of their dry weight were not significantly different among different species and had little meaning for water availability to the leaves, since twig thickness and dry weight of leaves per twig varied in different species. 2. Defoliated branches 6 feet long retained water longer than foliated ones in every species over a 3-5-day period, as determined by sectioning the branches and determining the water content by oven-drying. Ponderosa pine had the highest average water content in untreated, freshly cut branches. Toluene-extraction determinations with these branch sections showed that only a small error (1.2-0.4% on fresh weight) was involved in the oven-dry method; they were usually a little lower than the oven-dry determinations in moisture percentage indicated. 3. Analyses of trunk water showed that heartwood water varied considerably from one species to another, the heartwood of ponderosa pine and grand fir being high in water content and that of Douglas fir and red cedar being quite low. Determinations of total trunk water content were slightly higher in grand fir and ponderosa pine than in Douglas fir and red cedar. Seasonal changes in water content of the trunks in Douglas fir and ponderosa pine showed a definite annual cycle of increase and decrease, apparently depending on the weather.
Über Die Vertikalverteilung Und Den Massenwechsel Der Nematoden in Waldböden Mitteldeutschlands

Die Nematodenfauna mitteldeutscher Waldboden ist vorwiegend auf Horizonte mit organischen Substanzen beschrankt. Die Vertikalverteilung wies in Laubwaldboden zwei Entwicklungszentren auf. Im Bereich des Vermoderungshorizontes dominierten Arten, die sich vorwiegend von Bakterien ernahren. In tieferen Schichten, die aus Humus-Mineralboden-Gemisch bestehen, uberwiegen grose, stacheltragende Arten, die sich teilweise durch Anstechen und Aussaugen von Wurzeln ernahren. In Nadelwaldboden ist das untere Entwicklungszentrum nicht typisch ausgepragt. Der Jahresrhythmus der Populationsdichte zeigt Korrelationen zur Bodentemperatur.
Strategic Selection of Exogenous Enzymes for Corn/soy-based Poultry Diets

The usefulness of carbohydrases in corn/soy-based diets for poultry is still unclear and all the more so when phytase is present in the feed. Though there are many interacting factors involved in dictating the measured response to an exogenous enzyme the most influential is the nutritional value of the diet to which it is added. The inherent ileal digestibility of starch, protein and lipid in a corn/soy-based diet varies from around 70% to over 95% and this variance explains up to 90% of the variance in enzyme response. An appreciation for the concentration of undigested starch, protein and lipid in any given diet is an important starting point for the prediction of the effect of the enzyme on digestible energy and amino acids. Instructively, around 15-25% of this undigested fraction can be rendered digestible with the addition of xylanase and so the magnitude of the response is largely explained by the quantity of this undigested portion. As phytase improves the digestibility of the diet, effectively reducing the concentration of undigested amino acids and energy it can be predicted that xylanase will deliver less value in a diet which has already been improved with phytase. It is the purpose of the current paper to describe these effects and the implications for the strategic selection of enzymes for corn/soy-based poultry diets.
Trampling effects of hikers, motorcycles and horses in meadows and forests.

(1) The effects of experimental trampling due to hikers, horses, and motorcycles were studied in a Festuca idahoensis-Poa pratensis meadow and in a Pinus albicaulis-Vaccinium scoparium forest. (2) Horses and motorcycles were more damaging than hikers. Motorcycles were most damaging when going uphill while hikers and horses were most damaging when going downhill. (3) Damage was less rapid in grassy vegetation than in shrubby vegetation. (4) Damage was generally greater on slopes than on level ground.
Mechanisms of resistance to the brown planthopper Nilaparvata lugens in wild rice (Oryza spp.) cultivars

Three wild rice species and six cultivated rice varieties were evaluated to determine their mechanisms of resistance to Nilaparvata lugens (Stal.). Wild rice species, Oryza officinalis, O. punctata, and O. latifolia and cultivated rices Rathu Heenati (Bph 3), Babawee (bph 4), ARC 10550 (bph 5), Swarnalata (Bph 6), Ptb 33 (bph 2 + Bph 3) and the susceptible Taichung Native (TN 1) (no resistance gene) were included in the study. In a free choice seedbox screening test, wild rice species maintained their high level of resistance through the 48 h exposure to N. lugens nymphs while plant damage ratings of cultivated rice varieties increased with time. Wild rices were non preferred and significantly more individuals settled on susceptible TN 1 followed by cultivated rices. The quantity of food ingested and assimilated by N. lugens on wild rices was less than on cultivated resistant varieties. N. lugens caged on resistant wild rices had slow nymphal development, reduced longevity, low fecundity, and low egg hatchability as compared to N. lugens on cultivated resistant varieties.
Effects of Metabolism and Physiology on the Production of Okenone and Bacteriochlorophyll a in Purple Sulfur Bacteria

Purple sulfur bacteria (PSB) are important photoautotrophs inhabiting chemoclines in euxinic and meromictic lakes. These organisms are the only producers of the carotenoid, okenone, a compound that has been targeted as a biomarker for photic zone euxinia, particularly in ancient sedimentary environments. Although the natural occurrence and geochemistry of this compound has been studied previously, this is the first systematic and comprehensive report on the microbial physiology of okenone production in pure cultures. Four strains/species: Marichromatium purpuratum DSMZ 1591, Marichromatium purpuratum DSMZ 1711, Thiocapsa marina DSMZ 5653, and FGL21 (isolated from Fayetteville Green Lake, New York) were chosen because they produce okenone and Bacteriochlorophyll a (Bchl a). We developed a new, in vivo technique for the quantification of okenone allowing for more rapid and accurate quantification. The ratio of okenone to Bchl a differs among species and strains of PSB, varying from 0.463 ± 0.002 to 0.864 ± 0.002. Photoheterotrophically grown PSB have statistically significant, lowered okenone:Bchl a ratios, decreasing from 0.784 ± 0.009 under autotrophic metabolism to 0.681 ± 0.002, which we interpret to indicate a decreased requirement for okenone when PSB are provided with a complex (> C1) carbon source. The variation in okenone production raises the question on whether okenone expression is constitutive or inducible. The broader implication is that concentrations of okenone in sediments are dependent on metabolism and species composition, and not solely on PSB cell density.
CONTROL OF THE SOUTHERN CHINCH BUG, BLISSUS INSULARIS, IN SOUTH FLORIDA'

Insecticide tests for the control of Blissus insularis Barber on St. Augustinegrass were conducted in 1971. Akton, 0-(2-chloro-1-(2,5-dichlorophenyl)vinyl) 0,0-diethyl phosphorothioate; propyl thiopyrophosphate; diazinon; chlorpyrifos; Dyfonate, 0-ethyl S-phenyl ethylphosphonodithioate; ethion; and Nemacide, 0-(2,4-dichlorophenyl) 0,0-diethyl phosphorothioate, gave the best control.
Efficacy of artificial shelters for roach, Rutilus rutilus, against predators in the presence of reeds

Cormorants, Phalacocorax spp. , have great potential to affect recreational fisheries and have increased substantially in abundance over the last decades in UK inland waters. Fabricated refuges provide a potential means of reducing fish losses, yet the benefits of such structures may be marginal if natural shelters are abundant and favoured, or if strong density-dependence limits refuge use. This study examined the efficacy of artificial shelters in mesocosm enclosures that allowed standardised and replicated observations of roach, Rutilus rutilus (L.), distribution. When given a choice between occupying open water, simulated reedbeds and artificial brushwood shelters, roach used brushwood shelters extensively across a range of fish densities. When fish had a choice of occupying open water or reedbeds offering no overhead cover, they actively avoided reedbeds and used open water almost exclusively. Occupation of reedbeds was positively related to the amount of overhead cover they provided. When artificial brushwood shelters and reedbeds offered complete overhead cover, brushwood shelters were occupied twice as much as reedbeds. Artificial shelters may therefore have wide application in stillwaters with abundant reedbeds unless the reedbeds are coupled with extensive overhead cover.
Comparison of the Two Murine Deoxynucleotidyltransferase Terminal Isoforms

Terminal deoxynucleotidyltransferase (TdT) catalyzes the addition of nucleotides to 3′-hydroxyl ends of DNA strands in a template-independent manner and has been shown to add N-regions to gene segment junctions during V(D)J recombination. TdT is highly conserved in all vertebrate species, with a second isoform, characterized by a 20-amino acid insertion near the COOH-terminal end, described only in the mouse. The two murine isoforms differ in their subcellular localization, and the long isoform (TdTL) has previously been found to be unable to add N-regions. Using purified protein produced in a high level expression system in Escherichia coli, we were able to carry out detailed catalytic comparisons of these two TdT isoforms. We discovered that TdTL exhibits terminal transferase activity with kinetic parameters similar to those of the conserved TdT isoform (TdTS). We observed, however, that TdTL is inactivated at physiologic temperature but stable at lower temperatures. This thermal sensitivity of TdTL polymerase activity is not correlated with a significant change in the circular dichroism spectrum of the protein. Thus, the 20-amino acid insertion in TdTL does not affect the catalytic activity but modifies the thermosensitivity.
Bacterial Diversity at Different Sites of the Digestive Tract of Weaned Piglets Fed Liquid Diets

Bacterial diversity was studied using PCR-DGGE, cloning and sequencing. DNA was isolated from digesta samples from stomach, ileum and colon of 28 weaned piglets (Large WhiteMong Cai) fed dry control feed, naturally fermented liquid feed (FE) and a liquid diet with inclusion of rice distiller's residue feed. General bacterial diversity was described using DGGE analysis of the V3 region of 16S rDNA. The microbial populations in the stomach and the ileum were considerably influenced by the diet, while only marginal effects were observed in the colon. There was a large variation of the microbial flora in the stomach between individuals fed non-fermented diets. In contrast, animals fed diet FE had a more uniform microbial flora in the stomach and the ileum compared to the other diets. In total 47 bands from the DGGE profiles were cloned. In stomach, most frequently lactic acid bacteria were found. Feeding diet FE resulted in the occurrence of Pediococcus species in stomach and ileum. In pigs fed the other diets, Lactobacillus gallinarum, Lactobacillus johnsonii and Lactobacillus fermentum were found in stomach and ileum. Most of the sequences of bands isolated from colon samples and several from ileum matched to unknown bacteria, which often grouped within Prevotellaceae, Enterobacteriaceae, Bacteroidaceae and Erysipelotrichaceae. This study demonstrates that fermented liquid feed affects bacterial diversity and the specific microflora in stomach and ileum, which provides a potential to modulate the gut microflora with dietary means to increase the abundance of beneficial bacteria and improve piglets' health.