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The Square Kilometre Array (SKA) is a planned large radio interferometer designed to operate over a wide range of frequencies, and with an order of magnitude greater sensitivity and survey speed than any current radio telescope. The SKA will address many important topics in astronomy, ranging from planet formation to distant galaxies. However, in this work, we consider the perspective of the SKA as a facility for studying physics. We review four areas in which the SKA is expected to make major contributions to our understanding of fundamental physics: cosmic dawn and reionisation; gravity and gravitational radiation; cosmology and dark energy; and dark matter and astroparticle physics. These discussions demonstrate that the SKA will be a spectacular physics machine, which will provide many new breakthroughs and novel insights on matter, energy, and spacetime.
Human neurocysticercosis (NCC) is a worldwide neglected disease caused by Taenia solium metacestode and responsible for various complications and neurological disorders. This study aimed to evaluate the use of specific immunoglobulin Y (IgY) produced by laying hens immunized with a hydrophobic fraction of Taenia crassiceps metacestodes (hFTc) in NCC diagnosis. Egg yolk IgY antibodies were fractionated, purified and characterized. Enzyme-linked immunosorbent assay (ELISA) was carried out to evaluate the production kinetics and avidity maturation of anti-hFTc IgY antibodies throughout the IgY obtention process. Antigen recognition tests were carried out by Western blotting and immunofluorescence antibody test using purified and specific anti-hFTc IgY antibodies for detection of parasitic antigens of T. crassiceps and T. solium metacestodes. Sandwich ELISA was performed to detect circulating immune complexes formed by IgG and parasitic antigens in human sera. The results showed high diagnostic values (93.2% sensitivity and 94.3% specificity) for immune complexes detection in human sera with confirmed NCC. In conclusion, specific IgY antibodies produced from immunized hens with hFTc antigens were efficient to detect T. solium immune complexes in human sera, being an innovative and potential tool for NCC immunodiagnosis.
The rocky shores of the north-east Atlantic have been long studied. Our focus is from Gibraltar to Norway plus the Azores and Iceland. Phylogeographic processes shape biogeographic patterns of biodiversity. Long-term and broadscale studies have shown the responses of biota to past climate fluctuations and more recent anthropogenic climate change. Inter- and intra-specific species interactions along sharp local environmental gradients shape distributions and community structure and hence ecosystem functioning. Shifts in domination by fucoids in shelter to barnacles/mussels in exposure are mediated by grazing by patellid limpets. Further south fucoids become increasingly rare, with species disappearing or restricted to estuarine refuges, caused by greater desiccation and grazing pressure. Mesoscale processes influence bottom-up nutrient forcing and larval supply, hence affecting species abundance and distribution, and can be proximate factors setting range edges (e.g., the English Channel, the Iberian Peninsula). Impacts of invasive non-native species are reviewed. Knowledge gaps such as the work on rockpools and host–parasite dynamics are also outlined.
We assessed self-reported drives for alcohol use and their impact on clinical features of alcohol use disorder (AUD) patients. Our prediction was that, in contrast to “affectively” (reward or fear) driven drinking, “habitual” drinking would be associated with worse clinical features in relation to alcohol use and higher occurrence of associated psychiatric symptoms.
Fifty-eight Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) alcohol abuse patients were assessed with a comprehensive battery of reward- and fear-based behavioral tendencies. An 18-item self-report instrument (the Habit, Reward and Fear Scale; HRFS) was employed to quantify affective (fear or reward) and non-affective (habitual) motivations for alcohol use. To characterize clinical and demographic measures associated with habit, reward, and fear, we conducted a partial least squares analysis.
Habitual alcohol use was significantly associated with the severity of alcohol dependence reflected across a range of domains and with lower number of detoxifications across multiple settings. In contrast, reward-driven alcohol use was associated with a single domain of alcohol dependence, reward-related behavioral tendencies, and lower number of detoxifications.
These results seem to be consistent with a shift from goal-directed to habit-driven alcohol use with severity and progression of addiction, complementing preclinical work and informing biological models of addiction. Both reward-related and habit-driven alcohol use were associated with lower number of detoxifications, perhaps stemming from more benign course for the reward-related and lack of treatment engagement for the habit-related alcohol abuse group. Future work should further explore the role of habit in this and other addictive disorders, and in obsessive-compulsive related disorders.
This paper describes a model of electron energization and cyclotron-maser emission applicable to astrophysical magnetized collisionless shocks. It is motivated by the work of Begelman, Ergun and Rees [Astrophys. J. 625, 51 (2005)] who argued that the cyclotron-maser instability occurs in localized magnetized collisionless shocks such as those expected in blazar jets. We report on recent research carried out to investigate electron acceleration at collisionless shocks and maser radiation associated with the accelerated electrons. We describe how electrons accelerated by lower-hybrid waves at collisionless shocks generate cyclotron-maser radiation when the accelerated electrons move into regions of stronger magnetic fields. The electrons are accelerated along the magnetic field and magnetically compressed leading to the formation of an electron velocity distribution having a horseshoe shape due to conservation of the electron magnetic moment. Under certain conditions the horseshoe electron velocity distribution function is unstable to the cyclotron-maser instability [Bingham and Cairns, Phys. Plasmas 7, 3089 (2000); Melrose, Rev. Mod. Plasma Phys. 1, 5 (2017)].
The objective of the current experiment was to determine the effects of increasing levels of palm kernel cake in a finishing diet on feed intake, digestibility, performance, ingestive behaviour and carcass traits in zebu bulls. Thirty-two Nellore bulls (420 ± 25.0 kg initial body weight [BW] and 24-months-old), were assigned randomly to individual pens with four treatments (0, 70, 140 and 210 g/kg of palm kernel cake by total dry matter [DM]) and eight replicates per treatment. The inclusion of palm kernel cake linearly decreased DM, crude protein and non-fibrous carbohydrate intake and increased ether extraction intake and digestibility. There was a linear decrease in final BW and hot carcass weight (HCW) associated with palm kernel cake inclusion in the bull diet. However, the gain : feed ratio was similar among the diets. Eating and rumination rates (g DM or neutral detergent fibre/h) were reduced, whereas the total chewing time and idling (min/day) were not affected by palm kernel cake inclusion. There were no effects of palm kernel cake inclusion on most quantitative carcass characteristics and qualitative carcass attributes (subcutaneous fat thickness, longissimus muscle area, colour, texture and marbling). The inclusion of palm kernel cake (up to 210 g/kg total DM) in beef cattle finishing diets decreased eating and rumination rates, thereby decreasing average daily gain and, consequently, final BW and HCW. However, qualitative carcass attributes were not affected by the use of palm kernel cake.
Having disk-to-star accretion rates on the order of 10-4M⊙/yr, FU Orionis-type stars (FUors) are thought to be the visible examples for episodic accretion. FUors are often surrounded by massive envelopes, which replenish the disk material and enable the disk to produce accretion outbursts. We observed the FUor-type star V346 Nor with ALMA at 1.3 mm continuum and in different CO rotational lines. We mapped the density and velocity structure of its envelope and analyzed the results using channel maps, position-velocity diagrams, and spectro-astrometric methods. We discovered a pseudo-disk and a Keplerian disk around a 0.1 M⊙ central star. We determined an infall rate from the envelope onto the disk of 6×10-6M⊙/yr, a factor of few higher than the quiescent accretion rate from the disk onto the star. This hints for a mismatch between the infall and accretion rates as the cause of the eruption.
We performed a new series of measurements on samples that were part of early measurements on radiocarbon (14C) dating made in 1948–1949. Our results show generally good agreement to the data published in 1949–1951, despite vast changes in technology, with only two exceptions where there was a discrepancy in the original studies. Our new measurements give calibrated ages that overlap with the known ages. We dated several samples at four different laboratories, and so we were also able to make a small intercomparison at the same time. In addition, new measurements on samples from other Egyptian materials used by Libby and co-workers were made at UC Irvine. Samples of tree rings used in the original studies (from Broken Flute Cave and Centennial Stump) were obtained from the University of Arizona Laboratory of Tree-Ring Research archive and remeasured. New data were compared to the original studies and other records.
The in vitro larvicidal and in vivo anthelmintic effects of Oxalis tetraphylla hydroalcoholic extract (HE), against Haemonchus contortus in experimentally infected lambs, were assessed. We used a microtitration plate method, comprising the following two stages. Stage 1: 20 μl of water containing 200 sheathed H. contortus infective larvae (ShHcl) were deposited in every well of three series; then, the series 2 and 3 wells were treated with 80 μl 1% ivermectin and O. tetraphylla HE at 20 mg/ml, respectively. Stage 2: the same procedure was performed replacing the ShHcl with exsheathed larvae (ExShHcl). Evaluations were performed after 24 and 48 h. The total numbers of dead and live larvae were counted. A second experiment evaluated the reduction in nematode egg populations in the faeces of lambs treated orally with the O. tetraphylla HE. The 27 lambs used were divided into Groups 1, 2 and 3 (n = 9), which were administered water (positive control), levamisole 1 m (7.5 mg/kg body weight (BW), as a unique dose) and O. tetraphylla HE (20 mg/kg BW), respectively. The plant HE was administered daily for 8 days. The in vitro assay showed 80.9% and 86.5% larval mortality of ShHcl after 24 and 48 h, respectively, while the corresponding mortality values for ExShHcl were 97 and 99%, respectively. The in vivo assay showed variability in the eggs/gram of faeces (epg) values; however, at the end of the trial, the average reduction in the epg values of the O. tetraphylla HE group was 45.6% (P < 0.05). Oxalis tetraphylla HE contains compounds that belong to the flavonol group with anthelmintic activity.
There is an increasing interest in improving neurocysticercosis (NCC) diagnosis through the search of new and alternative antigenic sources, as those obtained from heterologous antigens. The aim of this study was to obtain potential biomarkers for NCC diagnosis after gel filtration chromatography [gel filtration fraction (GFF)] from the total saline extract (SE) from Taenia saginata metacestodes, followed by protein identification and application in immunodiagnostic. SE and GFF proteic profiles were characterized in gel electrophoresis, and diagnostic performance was verified by testing 160 serum samples through enzyme-linked immunosorbent assay and immunoblotting. Sensitivity (Se), specificity (Sp) and other diagnostic parameters were calculated. Polypeptides of interest in the diagnosis of human NCC present at GFF were analysed by mass spectrometry (MS) and B-cell epitopes were predicted. GFF had the best diagnostic parameters: Se 93·3%; Sp 93%; AUC 0·990; LR+ = 13·42 and LR− = 0·07, and proved to be useful reacting with serum samples in immunoblotting. Proteic profile ranged from 64 to 68 kDa and enolase and calcium binding protein calreticulin precursor were identified after MS. The enolase and calcium-binding protein calreticulin precursor showed 18 and 10 predicted B-cell epitopes, respectively. In conclusion we identified important markers in the GFF with high efficiency to diagnose NCC.
Human toxocarosis is a chronic tissue parasitosis most often caused by Toxocara canis. The seroprevalence can reach up to 50%, especially among children and adolescents. The anthelmintics used in the treatment have moderate efficacy. The aim of this study was to evaluate the in vitro and in vivo anthelmintic activity of quinones and their derivatives against T. canis larvae and the cytotoxicity of the larvicidal compounds. The compounds were evaluated at 1 mg mL−1 concentration in microculture plates containing third stage larvae in an Roswell Park Memorial Institute (RPMI) 1640 environment, incubated at 37 °C in 5% CO2 tension for 48 h. Five naphthoxiranes were selected for the cytotoxicity analysis. The cell viability evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and lactate dehydrogenase assays using murine peritoneal macrophages isolated from C57BL/6 mice revealed that the naphthoxiranes (1 and 3) were less cytotoxic at a concentration of 0·05 mg mL−1. The efficacy of naphthoxiranes (1 and 3) was examined in murine toxocarosis also. The anthelmintic activity was examined by evaluating the number of larvae in the brain, carcass, liver, lungs, heart, kidneys and eyes. Compound (3) demonstrated anthelmintic activity similar to that of albendazole by decreasing the number of larvae in the organs of mice and thus could form the basis of the development of a new anthelmintic drug.
This paper studies the performance of (U, Pu)C fuel in a hexagonal assembly of a GFR (Gas Fast Reactor). The SCALE 6.0 (Standardized Computer Analysis for Licensing Evaluation version 6.0) code was used in the calculation. The goal is to evaluate the behavior of the infinite multiplication factor (kinf) for a heterogeneous assembly model using four nuclear data libraries: V6-238, V7-238, ENDF/B-VI.8 and ENDF/B-VII.0. The burnup of (U, Pu)C was performed by the TRITON-6 module, and the isotopic concentrations were evaluated during the cycle. The present work comprises calculations at Zero Power and Full Power condition. This study intends to achieve more information about different Fast Reactors.
The present study determined the mineralogy and thermal properties of kaolin from Acoculco (Puebla), at the eastern Trans-Mexican Volcanic Belt and compared it with the nearby deposits of Agua Blanca (Hidalgo) and Huayacocotla (Veracruz). The mineralogy of the kaolins was determined by X-ray diffraction, infrared spectroscopy and scanning electron microscopy. Thermal behaviour was studied by differential thermal analysis, dilatometry and hot-stage microscopy. The Acoculco deposit is composed mainly of kaolinite and SiO2 minerals. In the case of Agua Blanca and Huayacocotla, alunite is abundant in places and minor anatase is also present locally. The Acoculco kaolins are Fe-poor and relatively rich in some potentially toxic elements (Zr, Sb, Pb). They undergo a relatively small amount of shrinkage (∼3–4 vol.%), during firing at 20–1300°C and cooling down to 20°C, except when >10 wt.% alunite is present. These kaolins are a suitable raw material for the ceramics industry. Other applications (pharmaceuticals, cosmetics) would require an enrichment process to eliminate impurities such as Fe oxides.
Boron nitride nanotubes (BNNTs), an analogue of carbon nanotube (CNT) is one of the most used non-metallic materials in high technology applications related to thin film fabrications. Taking advantage of their unique properties such as electrically non-conductive, thermally conductive, and high hardness, it has been used in high-temperature electronic devices, multifunctional aerospace materials, and structures and electric and aerospace systems. The main goal of this project was to use BNNTs in the fabrication of nano epoxycomposites to enhance their thermal and mechanical properties to use it for applications in aerospace constituents. In order to accomplish this goal, BNNTs were functionalized with isopherone diisocyante (IPDC). Surface analysis techniques were employed to ensure the modification BNNTs and study the interface of the reinforced composites before and after the modification. Mechanical and thermal conductivity testing was performed in order to understand the quality of the composites. Three different nanocomposites were accomplished with hBN and BNNTs using two different epoxy polymers and three curing agents. The systems EPON 862/Curing Agent W/ (hBN or BNNTs) have Tgs and tan deltas higher compared with those fabricated at the same conditions without nanoparticles. The fabricated BN composites showed improved physical properties due to their particle dispersion and boron nitrite intermolecular interactions with the epoxy polymer.
The highlight of this work is the synthesis of copper sulfide nanocrystals by a simple one-pot colloidal process, and the study of its electrochemical, electrical and morphological properties. Nanocrystals of Cu1.8S of about 15-30 nm were obtained at a temperature of 240°C under an argon atmosphere. The colloidal solution of the nanocrystals was analyzed by cyclic voltammetry. Agreeing to the values of EOx and ERedvs. SCE, and the average of three samples the HOMO and LUMO levels are 6.16 and 4.27 eV, respectively, the calculated HOMO – LUMO (Eg) is 1.89 eV. The Eg value, differs of that value obtained from Kubelka-Munk equation (1.7 eV). The photocurrent vs. time results showed that the Cu1.8S/Cu junction is photosensitive and could be used as absorbing material. The morphology and the topography of the film were analyzed by SEM and AFM techniques. Irregular agglomeration of nanocrystals was observed and a roughness of about 194 nm.
Rickettsia rickettsii infection is being increasingly recognized as an important cause of fatal acute illness in Brazil, where this tick-borne disease is designated Brazilian spotted fever (BSF). In this study we report five fatal cases of BSF in employees of an animal shelter in an urban area in the municipality of Rio de Janeiro in southeast Brazil after a natural disaster on 11 January 2011. Four of the cases occurred from 27 January to 11 April 2011, while the fifth fatal case was identified in April 2012. Three cases were confirmed by molecular analysis and two by epidemiological linkage. An investigation of BSF was performed in the animal shelter, and blood samples were collected from 115 employees and 117 randomly selected dogs. The presence of high levels (1024–4096) of antibodies against spotted fever group rickettsiae was found in three (2·6%) employees and 114 (97·5%) dogs. These findings emphasize the need to consider BSF as a possible cause of undifferentiated febrile illness, especially dengue and leptospirosis, in patients occupationally exposed to dogs heavily infested by ticks, mainly working at kennels and animal shelters that have inadequate space for the animals housed and frequently providing an environment conducive to exposure to pathogens such as R. rickettsii.