To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure email@example.com
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
With still limited information on vitamin requirements and considering that many commercial practices adopt dietary vitamin levels above the values suggested by nutritional tables, this study aimed to assess the effect of administering vitamin supplementation to sows in gestation and lactation and to their litters on the reproductive performance and body condition of the sows and on the performance and immune profile of the litters until slaughter. The trial was split into two phases. The first phase used 104 sows, assigned to be randomized to blocks according to parity, submitted until 21 days of lactation to two treatments: control–standard (standard levels of vitamins) and test–elevated (elevated levels of vitamins). Each sow and its respective farrow were considered an experimental unit. The sows underwent evaluations of body condition score, back fat thickness and reproductive performance. In the second phase, 60 barrows and 60 gilts at 21 days of age and mean initial weight of 5.33 ± 1.5 kg until slaughter at 164 days of age. The piglets were assigned to randomized blocks according to the weight and sex of the animals in a 2 × 2 factorial model, with 10 replicates per treatment, where a pen with three animals represented the experimental unit. Following the same treatments of the first phase, the piglets were evaluated for daily weight gain, daily feed intake, feed conversion, mortality rate and humoral immune response. Vitamin supplementation had no positive effects on the reproductive parameters or body composition of sows. However, it positively impacted the performance of the litters in the early nursery stage, but did not lead to superior effects on the immune responses to vaccination against circovirus or mycoplasma.
Hepatocytes constitute the majority of hepatic cells, and play a key role in controlling systemic innate immunity, via pattern-recognition receptors (PRRs) and by synthesizing complement and acute phase proteins. Leishmania infantum, a protozoan parasite that causes human and canine leishmaniasis, infects liver by establishing inside the Kupffer cells. The current study proposes the elucidation of the immune response generated by dog hepatocytes when exposed to L. infantum. Additionally, the impact of adding leishmanicidal compound, meglumine antimoniate (MgA), to parasite-exposed hepatocytes was also addressed. L. infantum presents a high tropism to hepatocytes, establishing strong membrane interactions. The possibility of L. infantum internalization by hepatocytes was raised, but not confirmed. Hepatocytes were able to recognize parasite presence, inducing PRRs [nucleotide oligomerization domain (NOD)1, NOD2 and Toll-like receptor (TLR)2] gene expression and generating a mix pro- and anti-inflammatory cytokine response. Reduction of cytochrome P 450s enzyme activity was also observed concomitant with the inflammatory response. Addition of MgA increased NOD2, TLR4 and interleukin 10 gene expression, indicating an immunomodulatory role for MgA. Hepatocytes seem to have a major role in coordinating liver's innate immune response against L. infantum infection, activating inflammatory mechanisms, but always balancing the inflammatory response in order to avoid cell damage.
The goal of this study was to analyse the spatial pattern of tuberculosis (TB) mortality using different approaches, namely: mortality rates (MR), spatial relative risks (RR) and Bayesian rates (Global and Local) and their association with human development index (HDI), Global and its three dimensions: education, longevity and income. An ecological study was developed in Curitiba, Brazil based on data from Mortality Information System (2008–2014). Spatial scan statistics were used to compute RR and identify high-risk clusters. Bivariate Local Indicator of Spatial Associations was used to assess associations. MR ranged between 0 and 25.24/100.000 with a mean (standard deviation) of 1.07 (2.66). Corresponding values for spatial RR were 0–27.46, 1.2 (2.99) and for Bayesian rates (Global and Local) were 0.49–1.66, 0.90 (0.19) and 0–6.59, 0.98 (0.80). High-risk clusters were identified for all variables, except for HDI-income and Global Bayesian rate. Significant negative spatial relations were found between MR and income; between RR and HDI global, longevity and income; and Bayesian rates with all variables. Some areas presented different patterns: low social development/low risk and high risk/high development. These results demonstrate that social development variables should be considered, in mortality due TB.
Considering the impact of coastal dynamics on the radiocarbon (14C) marine reservoir effect (MRE), upwelling has the potential of enhancing marine influence, usually 14C depleted. Freshwater input can contribute either to increased reservoir offsets, when dead carbon from rock weathering is available, but also towards an atmospheric 14C signal, when the presence of terrestrial organic matter from catchment prevails. An overview of the MRE studies based on shellmounds on the coast of Rio de Janeiro reveals a pattern of negative local corrections for Saquarema and Rio das Ostras but positive values for Cabo Frio island, suggesting the presence of cold upwelling waters in Cabo Frio at 1.6–1.2 cal kBP. New results for a shellmound on the Ilha Grande island, in the western portion of the Rio de Janeiro coast, revealed a negative value at about 3 ka. We discuss distribution of MRE values and temporal variability in the region and their relation to ocean dynamics, continental input and the choice of marine organisms used for ∆R determination. A comparison of local reservoir offsets for the Saquarema region obtained from fish otolith and mollusk shells revealed similar ΔR distributions, showing that both materials can be equally used.
Concentrate mixtures fed ruminants generally are composed by cereals where phosphorus is present mainly in phytate form or phytin (Maga, 1982). Phytate phosphorus is thought to be completely available to ruminants due to the presence of phytase enzyme that hydrolyzes phytate phosphorus making it available for absorption. Researches have shown that this fact is not always true, depending on different conditions (Park et al., 2000). The aim of this paper was to study the influence of phytate phosphorus on calcium availability.
Primary seed dispersal of many rain-forest seeds occurs through defecation by mammals. Dung beetles are attracted to the defecations and through their dung-processing behaviour these insects change the initial pattern of seed deposition. Final seed deposition patterns, i.e. where and how seeds are deposited after dung beetle activity has taken place, may strongly depend on seed size. In this study we addressed the following question: Do different sizes of seeds have different deposition patterns following dung beetle processing? We conducted a field experiment in lowland Amazonian rain forest in Brazil using 200-g dung-piles containing seed mimics of three sizes: 3.5, 8.6 and 15.5 mm long. Seed deposition condition after dung beetle activity was dependent on seed size. Small seeds were more often buried in beetle tunnels, while medium and large seeds more often remained on the soil surface, either clean or still covered by dung. A low proportion of seeds of all sizes remained on the soil surface covered by loose soil excavated by dung beetles. We speculate that the latter deposition pattern, though not very frequent, might be highly favourable for both seed survival and seedling establishment.
Brazil has the largest market for organic products in Latin America, but only 1.04% of its agricultural land is utilized for organic production (OP). We compared organic and conventional production (CP) in economic and productivity terms using data from a randomized survey of 86 organic and conventional strawberry growers (response rate 85.2%) in Brazlândia, Federal District, Brazil. Probit model selection estimates showed that the use of technical assistance from rural extension and producer gender had no effect, but growers with greater age, higher indebtedness, smaller strawberry production area, more education and less experience on growing strawberries were more likely to produce organically. For growers with more than 5.6 years of education and less than 13.54 years of experience, more education and experience make them less likely to produce strawberry organically. Thus, we expect growers’ probabilities of conversion for strawberry OP will remain about the same over time in the study area. The average treatment effect for the treated (ATT) was estimated using nearest neighbor/propensity score matching and endogenous switching regression (ESR). These showed that producing strawberry organically had no effect on productivity or total cost per box, but increased revenue and profit per box, probably as a result of the price premium for organic strawberries. As only 4.8% of farmers had converted to organic production, conversion costs and non-economic factors, such as psychological factors and social capital, may be barriers to conversion.
Among other zooarchaeological remains, terrestrial snails’ shells from the Thaumastus and Megalobulimus genera are found in some Brazilian shellmounds, presenting a potential substitute for charcoal in radiocarbon dating analyses, as reliable representatives of the atmospheric carbon isotopic ratio. In this paper, we present statistically similar results of both charcoal and land snails samples from the same archaeological contexts in three settlements on the coast of Rio de Janeiro. The Manitiba I shellmound results range from 4.2 to 3.7 ka cal BP (95.4%), contemporary with the Saquarema shellmound, occupied during the period from 4.3 to 3.6 ka cal BP (95.4%). For the Usiminas shellmound, two groups of samples revealed different periods of time for two occupational layers from 2.3 to 2.1 ka cal BP (95.4%) and from 1.6 and 1.3 ka cal BP (95.4%). A model constraining each group of samples to within a single phase has a general agreement of 97% with only two outliers out of 22 dates, yielding minimum individual agreement of 74% and 7% posterior outlier probability for Saquarema shells. These are good examples of sites in which the occupation chronology can be successfully obtained by the radiocarbon dating of land snails.
In the near future, ruminants may be forced to consume low-quality water since potable drinking water will become increasingly scarce in some regions of the world. A completely randomized design trial was completed to evaluate the effect of increasing concentrations of total dissolved salts (TDS) (640, 3187, 5740 and 8326 mg TDS/l) in drinking water on the performance, diet digestibility, microbial protein synthesis, nitrogen (N) and water balance using 24 Red Sindhi heifers (200 ± 5 kg) that were fed Buffel (Cenchrus ciliaris) grass hay and concentrate in a ratio of 50 : 50. After a 15-day diet adaptation period, the digestion study was completed over a 5-day period and the performance trial was completed over a 56-day period. Dry matter intake, average daily gain, feed:gain, intake and digestibility of most feed components were unaffected by the concentration of salt in the water. However, intake and digestibility of neutral detergent fibre declined linearly as TDS inclusion rate increased. Further, the inclusion of TDS resulted in a linear increase in the intake of drinking water and total (food plus drinking) water intake. Similarly, TDS inclusion levels resulted in a linear increase in total water excretion, with urine being the major route of water excretion. In contrast, increasing concentrations of TDS caused a linear decrease in creatinine and allantoin excretions. Finally, increasing the inclusion rate of TDS resulted in a linear decrease in N retention and a linear increase in urinary N excretion, which may pose a considerable challenge for farmers with respect to the reduction and management of nutrient losses.
The Numeniini is a tribe of 13 wader species (Scolopacidae, Charadriiformes) of which seven are Near Threatened or globally threatened, including two Critically Endangered. To help inform conservation management and policy responses, we present the results of an expert assessment of the threats that members of this taxonomic group face across migratory flyways. Most threats are increasing in intensity, particularly in non-breeding areas, where habitat loss resulting from residential and commercial development, aquaculture, mining, transport, disturbance, problematic invasive species, pollution and climate change were regarded as having the greatest detrimental impact. Fewer threats (mining, disturbance, problematic native species and climate change) were identified as widely affecting breeding areas. Numeniini populations face the greatest number of non-breeding threats in the East Asian-Australasian Flyway, especially those associated with coastal reclamation; related threats were also identified across the Central and Atlantic Americas, and East Atlantic flyways. Threats on the breeding grounds were greatest in Central and Atlantic Americas, East Atlantic and West Asian flyways. Three priority actions were associated with monitoring and research: to monitor breeding population trends (which for species breeding in remote areas may best be achieved through surveys at key non-breeding sites), to deploy tracking technologies to identify migratory connectivity, and to monitor land-cover change across breeding and non-breeding areas. Two priority actions were focused on conservation and policy responses: to identify and effectively protect key non-breeding sites across all flyways (particularly in the East Asian- Australasian Flyway), and to implement successful conservation interventions at a sufficient scale across human-dominated landscapes for species’ recovery to be achieved. If implemented urgently, these measures in combination have the potential to alter the current population declines of many Numeniini species and provide a template for the conservation of other groups of threatened species.
In the present work, we assess the chronology of archaeological sites known as earthen mounds, commonly found at the Pampas biome, among the lowlands of Brazil, Uruguay, and Argentina. We focused on the Pontal da Barra settlement, which is a testimony of the long-term occupation of indigenous groups in the swamp and wet environment of Patos Lagoon, southern Brazil. A Bayesian chronological model based on the radiocarbon (14C) dating of 17 samples of fish otolith, 5 charcoal fragments, and 2 bones (human and dog) allowed determination of the beginning of the occupation as well as the occupational synchronism of the different mounds. The nature of the samples allows us to study the local 14C reservoir effect through the comparison between the group of marine and terrestrial samples, deriving a reservoir offset value of 63±53 14C yr for this particular area, indicating a strong freshwater influence in the lagoon system. We estimate the start of human intervention in the landscapes of southern Patos Lagoon to be around 2200 cal BP, with the most intense activity between 1800 and 1200 cal BP.
We conducted a survival analysis with competing risks to estimate the mortality rate and predictive factors for immunodeficiency-related death in people living with HIV/AIDS (PLWH) in northeast Brazil. A cohort with 2372 PLWH was enrolled between July 2007 and June 2010 and monitored until 31 December 2012 at two healthcare centres. The event of interest was immunodeficiency-related death, which was defined based on the Coding Causes of Death in HIV Protocol (CoDe). The predictor variables were: sociodemographic characteristics, illicit drugs, tobacco, alcohol, nutritional status, antiretroviral therapy, anaemia and CD4 cell count at baseline; and treatment or chemoprophylaxis for tuberculosis (TB) during follow-up. We used Fine & Gray's model for the survival analyses with competing risks, since we had regarded immunodeficiency-unrelated deaths as a competing event, and we estimated the adjusted sub-distribution hazard ratios (SHRs). In 10 012·6 person-years of observation there were 3·1 deaths/100 person-years (2·3 immunodeficiency-related and 0·8 immunodeficiency-unrelated). TB (SHR 4·01), anaemia (SHR 3·58), CD4 <200 cells/mm3 (SHR 3·33) and being unemployed (SHR 1·56) were risk factors for immunodeficiency-related death. This study discloses a 13% coverage by highly active antiretroviral therapy (HAART) in our state and adds that anaemia at baseline or the incidence of TB may increase the specific risk of dying from HIV-immunodeficiency, regardless of HAART and CD4.
The Total Solar Irradiance (TSI), which is the total radiation arriving at Earth's atmosphere from the Sun, is one of the most important forcing of the Earths climate. Measurements of the TSI have been made employing instruments on board several space-based platforms during the last four solar cycles. However, combining these measurements is still challenging due to the degradation of the sensor elements and the long-term stability of the electronics. Here we describe the preliminary efforts to design an absolute radiometer based on the principle of electrical substitution that is under development at Brazilian's National Institute for Space Research (INPE).
Little is known about the mental health of partners of survivors of high levels of trauma in post-conflict countries.
We studied 677 spouse dyads (n = 1354) drawn from a community survey (response 82.4%) in post-conflict Timor-Leste. We used culturally adapted measures of post-traumatic stress disorder (PTSD), psychological distress, explosive anger and grief.
Latent class analysis identified three classes of couples: class 1, comprising women with higher trauma events (TEs), men with intermediate TEs (19%); class 2, including men with higher TEs, women with lower TEs (23%); and class 3, comprising couples in which men and women had lower TE exposure (58%) (the reference group). Men and women partners of survivors of higher TE exposure (classes 1 and 2) had increased symptoms of explosive anger and grief compared with the reference class (class 3). Women partners of survivors of higher TE exposure (class 2) had a 20-fold increased rate of PTSD symptoms compared with the reference class, a pattern that was not evident for men living with women exposed to higher levels of trauma (class 1).
Men and women living with survivors of higher levels of trauma showed an increase in symptoms of grief and explosive anger. The manifold higher rate of PTSD symptoms amongst women living with men exposed to high levels of trauma requires replication. It is important to assess the mental health of partners when treating survivors of high levels of trauma in post-conflict settings.
This study evaluates the radiocarbon dating of ceramic samples from Tupiguarani sites in Brazil, a settlement type dating up to 3000 cal BP. In this work, residues from ceramic samples from four archaeological sites in Rio de Janeiro (Morro Grande, Serrano, Barba Couto, and Bananeiras) were analyzed. In order to identify the most suitable sample preparation protocols, the humic fraction was isolated from the bulk material at the Oxford Radiocarbon Accelerator Unit (ORAU), whereas the acid-base-acid (ABA) residue fraction method was applied at the Radiocarbon Laboratory of the Fluminense Federal University (LAC-UFF). The dating results were compared to the current knowledge about the occupational periods of the sites. For the Morro Grande site, the results of humic and ABA residue fractions show a difference of more than 1500 yr. For the Serrano site, the 14C ages obtained from the two pretreatments are identical, and as with the Barba Couto and Bananeiras sites, indicate an occupation during the Brazilian colonial period of the 16th century AD and are compatible with the archaeological data.
The regional component (∆R) of the marine reservoir effect (MRE), which is crucial for the accurate calibration of radiocarbon ages of marine-influenced samples, was determined for the Cuban northwestern coast. Fifteen different locations were studied by 14C dating of pre-bomb known-age marine shells specimens of bivalves and gastropods from the Felipe Poey Museum collection. Accelerator mass spectrometry (AMS) 14C measurements were performed at the Radiocarbon Laboratory of the Universidade Federal Fluminense (LAC-UFF) and mean ΔR values were estimated. The distribution of results indicates ∆R values from −46±38 to 140±52 14C yr and a possible pattern related to the position along the coast and ocean dynamics. We present both mean values for each region and a general ∆R of 28±13 14C yr for the northwestern coast of Cuba.
The Radiocarbon Laboratory of the Universidade Federal Fluminense, in Brazil, has been successfully applying the zinc reduction method for graphitization of carbon samples since the development of its early protocols in 2009. Successive methodological research aiming to improve and, ultimately, optimize the precision and accuracy of our results indicates that graphitization temperatures as low as 460°C promote erratic 13C isotopic fractionation, but an approximately constant fractionation of about –5‰ is achieved at 520°C. In this work, we present isotope ratio mass spectrometry (IRMS) δ13C results for 14C reference materials graphitized at 550°C with variable amounts of zinc. Based on the results obtained from the addition of 20, 35, and 50 mg of zinc, we conclude that a slightly lower variation in 13C isotope fractionation during graphitization is obtained with less zinc. Moreover, the average isotopic fractionation is not altered by increasing the graphitization temperature from 520°C to 550°C.
We describe the search for δ Scuti stars in the MACHO database of bulge fields. Concentrating on a sample of high amplitude δ Scutis, we examine the light curves and pulsation modes. We also discuss their spatial distribution and evolutionary status using mean colors and absolute magnitudes.
Real-time detection of microlensing has moved from proof of concept in 1994 (Udalski et al. 1994a, Alcock et al. 1994) to a steady stream of events this year. Global dissemination of these events by the MACHO and OGLE collaborations has made possible intensive photometric and spectroscopic follow up from widely dispersed sites confirming the microlensing hypothesis (Benetti 1995). Improved photometry and increased temporal resolution from follow up observations greatly increases the possibility of detecting deviations from the standard point-source, point-lens, inertial motion microlensing model. These deviations are crucial in understanding individual lensing systems by breaking the degeneracy between lens mass, position and velocity. We report here on GMAN (Global Microlensing Alert Network), the coordinated follow up of MACHO alerts.
We measure the ratio of ~ 5M⊙ blue and red LMC supergiants (representative of classical Cepheids) using the MACHO Project's 9 million star color-magnitude diagram (9M CMD) of the LMC bar. We find b/r = 0.39, which favors the Z=0.008, 5M⊙ theoretical model of Schaerer et al. (1993) over that of Fagatto et al. (1994). Next, we examine the low mass (old) and low metallicity LMC field population (Pop. II). Features in the 9M CMD and properties of LMC field RRab variables are consistent with a mean iron abundance of [Fe/H] ≈ −1.5 dex for this population. Newly discovered post-HB/early-AGB Pop. II variables are identified in order to delineate the instability strip (IS). Good agreement with the theoretical IS of Bono et al. (1997) is found. We then compare the field RRab with newly identified RRab variables in the LMC clusters NGC 1898 and NGC 1835. We find the mean colors of these cluster RRab lie near the red and blue edges of the IS, respectively, which is similar to their respective (overall) red and blue HB morphologies. Since the field RRab lie on the red side of the IS, we infer the LMC field Pop. II is likely to have a red HB morphology.