Miracle-dz/UniFAR-FTUs huggingface dataset:
The Effect of the Growth Medium on the Composition and Metal Binding Behaviour of the Extracellular Polymeric Material of a Metal-Accumulating Citrobacter sp.

Cells of a heavy metal-accumulating Citrobacter sp. appeared electron-opaque under the electron microscope when pre-grown in medium containing lactose and inorganic phosphate as the respective carbon and phosphorus sources, compared to cells supplied with glycerol and glycerol 2-phosphate. This was attributable to a greater proportion of bound metal cations, as analysed using proton induced X-ray emission analysis of extracted extracellular polymeric material (EPM). This was associated with a greater content of EPM-associated phosphorus and also an enhanced activity of isolated EPM to accumulate uranyl ion, to 23% of the polymer dry weight. EPM from glycerol 2-phosphate-grown cells, analysed using 31P nuclear magnetic resonance spectroscopy, gave several major phosphorus resonances between −1 and 2 ppm, in accordance with published spectra for enterobacterial lipopolysaccharide. Addition of Cd2+ promoted a shift downfield of the P resonances to a new, common, resonance at 3 ppm which was similar to that observed in native, Cd-unchallenged EPM obtained from inorganic phosphate-pregrown cells. The two types of polymer were morphologically distinct, with a shift to a more defined structure on addition of Cd2+ to the EPM from glycerol phosphate-grown cells. The two types of 31P spectra of the EPM were influenced by the pregrowth phosphorus source, and not by the carbon source. In contrast, analysis of the monosaccharide content of the EPM by gas chromatography and high performance liquid chromatography showed that the main components, rhamnose, glucose and ribose, were unaffected by the pre-growth phosphate source but cells pre-grown in glycerol medium had a higher proportion of glucose residues (ratios of glucose:rhamnose of 4:1 and 2.5:1 in glycerol and lactose-pregrown cells, respectively), and a higher content of EPM monosaccharides, overall, in the lactose-grown cultures. Restriction of carbon or nitrogen source by growth in continuous culture and analysis of the EPM gave major 31P resonances in the region of −1 to 3 ppm, while growth under phosphate-limiting continuous culture showed only one major species, at 1 ppm. The data illustrate that the composition of the cell surface polymers, and the ability of these to sorb heavy metal, are functions of the environment in which the cells are grown. This has implications in the application of biosorption techniques to the removal of heavy metals from wastes.
Prevalência para tuberculose caprina no semi-árido paraibano

Tuberculosis is an infectious disease of world wide distribution caused by pathogenic mycobacteria that affect humans and several mammals species. In order to determine the prevalence of tuberculosis in goats and to identify risk factors associated with infection, 1,866 goats of different breeds and ages from 84 herds in the microregion of Monteiro, State of Paraiba, Northeast Brazil, were tuberculinized by the Comparative Cervical Test (CCT). Interpretation of the CCT was checked by calculation of the difference obtained between skin measures correspondent to respective tuberculins, before and 72 hours after inoculation: negative, when bovine PPD is smaller than avian PPD or larger in up to 1.8mm; suspicious or inconclusive, reaction to bovine PPD larger than avian PPD between 1.9 and 2.4mm; positive, reaction to bovine PPD larger than or equal to avian PPD in 2.5mm. From goats submitted to CCT, 0.47% (9/1866) reacted positively (95% CI = 0.23%-0.94%). The prevalence of positive herds to caprine tuberculosis was 10.71% (95% CI = 5.02-19.37%). When submitted to necropsy and histopathologic examination, a positive goat at tuberculin test presented tuberculosis-like lesions. The presence of Acid-Alcohol Resistant Bacilli (BAAR) was also detected by direct bacterioscopy; in relation to herd size, herds with larger number of animals ( >25) with high incidence of the disease, and presence of the infection was evidenced in properties that raised cattle in association with goats and did not carry out tuberculin tests in cattle.
The Business Cycles Implications of Fluctuating Long Run Expectations

I consider a real-business cycle, DSGE model where consumption is a function of the present discounted value of wage and capital income. The agent is uncertain if these income variables are stationary or non-stationary and puts positive probability on both representations. The agent uses Bayesian learning to update his probability weights on each model and these weights vary over time according to how well each model fits the data. The model exhibits an improved fit to the data relative to the rational expectations benchmark. The model requires half the level of exogenous shocks to match the volatility of output and still matches the relative volatilities of key business cycle variables. The model lowers the contemporaneous correlation of consumption and wages with output and generates positive auto-correlation in model growth rates. Impulse responses exhibit persistent responses and consistent with survey evidence forecast errors are positively serially correlated. Finally, in contrast to the existing literature, the model endogenously generates observed time varying volatility and long run predictability of business cycle variables, especially for investment.
Monetary Policy, De-Anchoring of Inflation Expectations, and the 'New Normal'

Low inflation rates in the Euro Area raise the question of whether inflation is still credibly anchored to the Euro-system’s medium term target of below, but close to 2%. The purpose of this paper is twofold. On the one hand, we investigate why agents’ inflation expectations that inflation will remain in line with the target begin to falter. On the other hand, we want to study how the de-anchoring of expectations interacts with monetary policy determining whether the central bank is still able to achieve its target - and hence re-anchor inflation expectations - or whether the system drifts away towards the liquidity trap. Two are our main findings. The first is that large unfavourable shocks might lead agents to question their trust in resilience of the system, and to revise their expectations. If inflation expectations fall faster than the policy rate, and the zero lower bound is reached without correcting the interest-rate gap, the system converges to a new steady state - the “new normal” - with permanent negative gaps. The second is that a more aggressive monetary policy is ineffective both at the ZLB and above the ZLB, when the shock is large shocks and/or when the reactivity of inflation expectations is high enough. This last finding seems to support the necessity, in those conditions, to abandon conventional monetary policy and to switch to an aggressive reflationary policy that prevents the entrenchment of deflationary expectations.
Weed control in tropical ley farming systems: a review

The first sustained effort to develop a ley farming system (a pasture legume rotated with a grain crop) for the Australian semi-arid tropics began in the late 1970s at Katherine, Northern Territory, where various strategies were identified and implemented. It was soon discovered that a main constraint to success was the invasion of the legume ley by grass weeds. This occurred despite the replacement of Townsville stylo (Stylosanthes humilis), which provided the base for the early work, with more competitive legumes such as Verano (Stylosanthes hamata) and Centurion centro (Centrosema pascuorum). Early weed control work focused on the use of chemicals, but later competition and population dynamics were studied in S. humilis pastures. The ley farming system comprised a number of essential elements, each of which offered opportunities for weed control First, a legume ley was rotated with grain crops. Past work concentrated on legume leys, but nitrogen (N)-fertilised grass leys may be successful if the N was economically supplied. Grasses can effectively suppress weeds. Rotation of herbicides is possible. Sicklepod (Senna obtusifolia) can be controlled with atrazine in the sorghum phase, and emergent Sida spp. can be controlled in the pasture phase using a herbicide roller. Second, cattle graze the legume ley and crop residues in the dry season. Cattle can be used to suppress grass weeds in the wet season. The major use of the legume ley, however, was to provide high quality food in the dry season when there was little other available food. Future research should investigate the economics of balancing the need for grass weed control with food provision in the dry season. Third, crops sown directly into a ley killed with a knockdown herbicide. Although the need for improved soil surface management was recognised early, development of reduced tillage was delayed until the availability of glyphosate. Initial work concentrated on improving plant establishment under mulch. Recent work has shown that mulches can effectively control weeds in crops without the use of herbicides; best weed control occurred when glyphosate was applied as a single application at sowing. Fourth, ley regenerated as an intercrop in the grain crop. There is no doubt that the presence of an intercrop reduces the yield of the grain crop. Future research should investigate the economics and risks associated with intercrop-induced changes in yield and herbicide use patterns. The extreme climate and sandy soils pose problems for herbicide use. There is marked seasonal variation in effectiveness of pre-emergence herbicides, ranging from zero to marked crop phytotoxicity. The effectiveness of knockdown herbicides is reduced by stressed target plants and rain soon after spraying. Mulch dynamics, grazing, competition and interference, and herbicide interactions with target plants and the environment, were identified as key features requiring attention in a ley farming system to achieve practical weed management.
Competitive Information Design

In this paper, we present a simple model of information provision in competitive markets. We depart from previous literature in that we allow firms to choose both prices and information revelation policies. Under the assumption that the underlying state is binary, we show that in the unique symmetric equilibrium firms randomize over binary experiments, and those firms that offer comparatively better deals disclose more information. Nevertheless, policies directed at increasing information disclosure relax competition and may reduce aggregate surplus. We provide several applications, including labor markets and venture capital financing.
Anisakidae parasitos de congro-rosa, Genypterus brasiliensis Regan, 1903 comercializados no estado do Rio de Janeiro, Brasil de interesse na saúde pública

The aim of this study was to identify the species Anisakidae, of interest to public health, parasitizing the cusk-eel, Genypterus brasiliensis Regan, 1903 purchased in markets ofNiteroi and Rio de Janeiro counties, Brazil, emphasizing their parasite indexes, sites of infection and higienic-sanitary importance. Seventy-four specimens ofG brasiliensis were necropsiedfrom October 2002 to September 2003. Twenty fish specimens (27%>) were parasitized by live larvae of Anisakidae. The collected species were represented by Anisakis physeteris, Anisakis simplex, Anisakis sp. , Pseudoterranova decipiens, Pseudoterranova sp. , Hysterothylacium sp. , Raphidascaris sp. , Contracaecum sp. and Terranova sp. The species Anisakis sp. and A. simplex presented the higher prevalences, both with 13,5% whereas A. physeteris presented the lower prevalence 1,35%. The other species, Pseudoterranova sp. , P. decipiens, Hysterothylacium sp. , Raphidascaris sp. , Contracaecum sp. and Terranova sp. presented prevalences of 10,8%, 5,4%, 2,7%, 4,1%, 1,4% and 1,4%, respectively. The sites of infection were, the mesentery, stomach and intestinal seroses, intestine, ovary and musculature.
Liquidity-Saving Mechanisms

We study the incentives of participants in a real-time gross settlement system with and without the addition of a liquidity-saving mechanism (queue). Participants in our model face a liquidity shock and different costs for delaying payments. They trade off the cost of delaying a payment against the cost of borrowing liquidity from the central bank. The heterogeneity of participants in our model gives rise to a rich set of strategic interactions. The main contribution of our paper is to show that the design of a liquidity-saving mechanism has important implications for welfare, even in the absence of netting. In particular, we find that parameters will determine whether the addition of a liquidity-saving mechanism increases or decreases welfare.
The Connexion between Old and New Approaches to Financial Satisfaction

In this paper we compare the new satisfaction evaluation approach, developed in the nineties by Oswald, Clark, Blanchflower and others with the older income evaluation (IEQ) approach, developed by Van Praag and Kapteyn in the seventies of the previous century. We find that both approaches yield strikingly similar results with respect to financial satisfaction. The IEQ-approach yields additional insights, but it is not well applicable to other life domains than finance. It is argued that the usual Probit specification implies a specific cardinalization and, consequently, is less ordinal than usually thought. It is shown that the Probit-approach may be replaced by three other equivalent specifications that have some computational and intuitive advantages.
Price Dispersion in Dynamic Competition

Substantial price dispersion exists for transactions of physically identical goods, and in these markets, incumbent sellers sell at higher prices than entrants. This study develops a theory of dynamic competition that explains these facts as results from the same fundamental friction: buyers are imperfectly aware of which sellers are operating, and the degree of awareness about a seller is endogenous. The equilibrium is unique and approximately efficient, featuring randomized pricing strategies where incumbents post higher prices than entrants. The equilibrium converges to a stationary equilibrium. If buyers' awareness does not depreciate and the exit rate of sellers converges to zero, then the stationary equilibrium converges to perfect competition.
Analysis of otolith 87Sr/86Sr to elucidate salinity histories of Nurseryfish Kurtus gulliveri (Perciformes:Kurtidae) in a tropical lowland river in northern Australia

The Nurseryfish Kurtus gulliveri is found in estuarine and freshwater reaches of tropical rivers in northern Australia and southern New Guinea. Nurseryfish have been recorded in salinities ranging from freshwater to seawater (salinity <0.5–36‰), but almost nothing is known of their movements. We conducted core-to-edge transect analyses of 87Sr/86Sr in the otoliths of 16 male and 14 female Nurseryfish collected from a tropical river in northern Australia to examine their movements across a freshwater–estuarine salinity gradient. Comparisons between water and otolith 87Sr/86Sr showed that most fish had 87Sr/86Sr values indicative of periods of saline (salinity > 4‰) residence during their early life history, usually followed by a distinct transition into brackish (0.5–4‰) or fresh water (<0.5‰) later in life. No differences were discernible between the salinity histories of male and female Nurseryfish. Analysis of the relationship between the otolith core-to-edge distance and fish mass indicated that most growth occurred in brackish water. We conclude that Nurseryfish are euryhaline rather than diadromous and that analysis of water and otolith 87Sr/86Sr is an effective method for assessing the movements of tropical riverine fishes and the potential importance of fish migration in driving foodweb subsidies.
Equilibrium Variance Risk Premium and Option Smirk in the AK Production Model

This paper extends the AK production model in Pindyck and Wang (2013) into a more general setting in which the volatility of capital stock is stochastic and driven by shocks. After solving the equilibrium, the fundamental shocks are embedded into the stock price and the leverage effect is contributed from three distinct channels. As two applications, we employ our extended AK production model to match well the negative variance risk premium and the Black-Scholes implied volatility surface.
Fire and the Angiosperm Revolutions

Fires have been burning plants since the early Devonian and were common in the Mesozoic, before angiosperms became prominent. Fires were common in the Cretaceous, when angiosperms first spread to cover significant areas of the world. We suggest that this spread was facilitated by intrinsic angiosperm properties that altered fire regimes in two fundamental ways. The first was to promote more frequent fires than the slower-growing gymnosperms that they replaced. The high productivity of angiosperms would have fueled more frequent fires, while reproductive innovations allowed for more rapid recovery, particularly in upland areas too dry for ferns. The evolution of flammable grasses is the latest expression of angiosperm innovation, generating even more frequent fires capable of carving into forests, particularly after the spread of C4 grasses from ∼8 Ma. The second major impact of angiosperms on fire was the development of forests. Closed broad-leaved forests fundamentally changed fire regimes by producing a vegetation structure that intrinsically excludes fires. No conifer analogues for fire-excluding forests seem to exist today or to have existed in the evolutionary past. Both fire-promoting and fire-excluding ecosystems are a product of angiosperm innovations. While these novel ecosystems may have caused the extinction of several ancient lineages, ferns and conifers still persist within them. One conifer lineage, the genus Pinus, has shown remarkable adaptability to highly flammable ecosystems, including frequently burned C4 grasslands.
Stock Market Liberalization and Corporate Investment Revisited

A recent reform in China, the Shanghai-Hong Kong Stock Connect program, made a subset of Chinese stocks investable for foreign investors, thus partially opening China’s stock market. We use this reform to examine the quantity and quality effects of stock market liberalization on corporate investment and address some of the data and methodological concerns raised in previous studies. Our difference-in-differences analysis shows that the reform boosts the investment of investable firms relative to non-investable firms. It also makes the investable firms’ investment more responsive to growth opportunities, increases their total factor productivity, and improves their operating performance. Further analysis finds that the reform increases equity issuance, reduces agency costs, and mitigates earnings management, which helps explain its quantity and quality effects on corporate investment.
Corporate Bonds with Implicit Government Guarantees

Implicit government guarantees benefit corporate bonds issued by state-owned enterprises (SOEs) through a solvency protection premium and a bailout premium. We expect poorly rated SOE bonds to have a stronger guarantee effect than highly rated SOE bonds and this is confirmed by empirical findings. For newly issued corporate bonds, the average guarantee premium is 72 basis points (bps) for AAA bonds while it rises to 166 bps for AA- (lowest issuance rating) bonds. We further detect a stronger guarantee effect among strategically important industries and issuers from regions of strong fiscal conditions.
Movements and Habitat Preference of Northern Pike (Esox lucius) in Lac Ste. Anne, Alberta

Abstract Movements of northern pike (Esox lucius) in Lac Ste. Anne, Alberta were monitored for 5 to 47 days using ultrasonic transmitters which were implanted in the fishes' stomachs. None of the nine fish studied established well-defined home ranges. The pike were usually found within 300 m of shore and in water less than 4 m deep. No major differences were found in the extent of movement or in habitat selection between summer and winter. Daily pike movements were from 0 to 4,000 m, but most daily movements were less than 1,000 m.
INTERACTIVE EFFECTS OF IRRADIANCE AND TEMPERATURE ON THE PHOTOSYNTHETIC PHYSIOLOGY OF THE PENNATE DIATOM PSEUDO‐NITZSCHIA GRANII (BACILLARIOPHYCEAE) FROM THE NORTHEAST SUBARCTIC PACIFIC 1

This study examined how light and temperature interact to influence growth rates, chl a, and photosynthetic efficiency of the oceanic pennate diatom Pseudo‐nitzschia granii Hasle, isolated from the northeast subarctic Pacific. Growth rates were modulated by both light and temperature, although for each irradiance tested, the growth rate was always the greatest at ∼14°C. Chl a per cell was affected primarily by temperature, except at the maximum chl a per cell (at 10°C) where the effects of light were noticeable. At both ends of the temperature gradient, cells displayed evidence of chlorosis even at low light intensities. Chl fluorescence data suggested that cells at 8°C were significantly more efficient in their photosynthetic processes than cells at 20°C, despite having comparable concentrations of chl. Cells at low temperature showed photosynthetic characteristics similar to high‐irradiance‐adapted cells. The decline of growth rates beyond the optimum growth temperature coincided with the cell's inability to accumulate chl in response to increasing temperature. The decline in photosynthetic ability at 20°C was likely due to a combination of high‐temperature stress on cellular membranes and a decline in chl. Our results highlight the important interactions between light and temperature and the need to incorporate these interactions into the development of phytoplankton models for the subarctic Pacific.
Effects of salinity on the germination and seedling characteristics of cowpea [Vigna unguiculata (L.) Walp.]

Cowpea [Vigna unguiculata (L.) Walp. ], a species with wide adaptation in arid and semi-arid zones, is grown from green seeds and pods, and is tolerant to salinity. It is a hardy species capable of developing in soils of low fertility. In this study, the effects of different salinities and different submersion times on the germination and weight of seeds of cowpea treated previously were evaluated. The effect of irrigation with saline solutions on seedling shoot length and dry weight, stem height and dry weight, total dry weight, and leaf area was also studied. The results show that the weight of pre-treated seeds decreases linearly when submersion times were increased. Germination decreased quadratically when submersion times and salinity increased. Seedling total dry weight, leaf area, shoot length and dry weight, stem height and dry weight all decreased quadratically significantly when salinity increased.
Cultural Dimensions, Collective Values and their Importance for Institutions

This paper critically assesses the role of culture in determining the quality of institutions. Employing various measures of cultural diff erences, I find that only diff erences related to the degree of individualism in society and the extent to which inequality in the distribution of power is tolerated are strong and statistically signi cant predictors of the observed diff erences in institutional quality. This fi nding is robust to the inclusion of various other determinants of institutional di fferences across countries discussed in the literature and it holds for a variety of measures of institutional quality. Moreover, the strong link between these two cultural dimensions and the quality of institutions is also con firmed in instrumental variables regressions where a novel instruments for culture based on a weighted average of the cultural attitudes present in neighboring countries is employed.