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Neospora caninum is a commonly diagnosed cause of reproductive losses in farmed ruminants worldwide. This study examined 495 and 308 samples (brain, heart and placenta) which were collected from 455 and 119 aborted cattle and sheep fetuses, respectively. DNA was extracted and a nested Neospora ITS1 PCR was performed on all samples. The results showed that for bovine fetuses 79/449 brain [17.6% (14.2–21.4)], 7/25 heart [28.0% (12.1–49.4)] and 5/21 placenta [23.8% (8.2–47.2)] were PCR positive for the presence of Neospora DNA. Overall 82/455 [18.0% (14.6–21.7)] of the bovine fetuses tested positive for the presence of N. caninum DNA in at least one sample. None (0/308) of the ovine fetal samples tested positive for the presence of Neospora DNA in any of the tissues tested. The results show that N. caninum was associated with fetal losses in cattle (distributed across South-West Scotland), compared to sheep in the same geographical areas where no parasite DNA was found. Neospora is well distributed amongst cattle in South-West Scotland and is the potential cause of serious economic losses to the Scottish cattle farming community; however, it does not appear to be a problem amongst the Scottish sheep flocks.
The use of cactus cladodes in animal feed is well-established in semi-arid areas. The cactus Nopalea cochenillifera (L.) Salm-Dyck cladodes (Nopalea) have high acceptability amongst dairy cows and are resistant to carmine cochineal insects (Dactylopius opuntiae Cockerell), a problem in semi-arid regions, but in regions of prolonged drought, it has lower productivity compared with the cactus Opuntia stricta (Haw.) Haw cladodes (Opuntia), which is also resistant to the insect. The objective of the current study was to evaluate the intake and content of digestible material of dry matter (DM) and its components, feeding behaviour, microbial protein synthesis, nitrogen balance, blood parameters, performance and milk composition of Holstein cows fed a control diet, containing either Nopalea or Opuntia associated with different concentrate levels (225, 275, 325 and 375 g/kg). Ten cows with an initial average milk production of 20 ± 2.1 kg/day were distributed into a double 5 × 5 Latin square design. Diets containing 775 g roughage/kg and 225 g concentrate/kg promoted similar responses to the analysed variables regardless of the cactus cladode used, except for digestibility of neutral detergent fibre. Diets containing higher proportions of concentrate (325 and 375 g/kg) promoted greater DM intake and 3.5% fat-corrected milk yield. The diet containing Opuntia at 775:225 g/kg roughage:concentrate proportion is as effective as the control diet for Holstein cows producing 20 kg of milk/day. To promote greater milk production, higher proportions of concentrate should be added to diets using Opuntia.
We report on the EPICA Dronning Maud Land (East Antarctica) deep drilling operation. Starting with the scientific questions that led to the outline of the EPICA project, we introduce the setting of sister drillings at NorthGRIP and EPICA Dome C within the European ice-coring community. The progress of the drilling operation is described within the context of three parallel, deep-drilling operations, the problems that occurred and the solutions we developed. Modified procedures are described, such as the monitoring of penetration rate via cable weight rather than motor torque, and modifications to the system (e.g. closing the openings at the lower end of the outer barrel to reduce the risk of immersing the drill in highly concentrated chip suspension). Parameters of the drilling (e.g. core-break force, cutter pitch, chips balance, liquid level, core production rate and piece number) are discussed. We also review the operational mode, particularly in the context of achieved core length and piece length, which have to be optimized for drilling efficiency and core quality respectively. We conclude with recommendations addressing the design of the chip-collection openings and strictly limiting the cable-load drop with respect to the load at the start of the run.
Next space missions will investigate the possibility of extinct or extant life on Mars. Studying the infrared spectral modifications, induced by thermal processing on different carbonate samples (recent shells and fossils of different ages), we developed a method able to discriminate biogenic carbonates from their abiogenic counterparts. The method has been successfully applied to microbialites, i.e. bio-induced carbonates deposits, and particularly to stromatolites, the laminated fabric of microbialites, some of which can be ascribed to among the oldest traces of biological activity known on Earth. These results are of valuable importance since such carbonates are linked to primitive living organisms that can be considered as good analogues for putative Martian life forms. Considering that the microstructures of biogenic carbonate are different from those of abiogenic origin, we investigated the micromorphology of shells, skeletal grains and microbialites at different scale with a scanning electron microscope. The results show that this line of research may provide an alternative and complementary approach to other techniques developed in the past by our group to distinguish biotic from abiotic carbonates. In this paper, we present some results that can be of valuable interest since they demonstrate the utility for a database of images concerning the structures and textures of relevant carbonate minerals. Such data may be useful for the analysis of Martian samples, coming from sample return missions or investigated by future in situ explorations, aimed to characterize the near-subsurface of Mars in search for past or present life.
This essay undertakes two tasks: first, to describe the differing mens rea requirements for accomplice liability of both Anglo-American common law and the American Law Institute's Model Penal Code; and second, to recommend how the mens rea requirements of both of these two sources of criminal law in America should be amended so as to satisfy the goals of clarity and consistency and so as to more closely conform the criminal law to the requirements of moral blameworthiness. Three "pure models" of the mens rea requirements for complicity are distinguished, based on the three theories of liability conventionally distinguished in the general part of Anglo-American criminal law. One of these, the vicarious responsibility model, is put aside initially because of both its descriptive inaccuracy and its normative undesirability. The analysis proceeds using the other two models: that of the mens rea requirements for principal liability for completed crimes, and that of the mens rea requirements for attempt liability. Both the common law and the Model Penal Code are seen as complicated admixtures of these two models, the common law being too narrow in the scope of its threatened liability and the Model Penal Code being both too broad and too opaque in its demands for accomplice liability. The normative recommendation of the paper is to adopt the model for the mens rea of complicity that treats it as a form of principal liability, recognizing that the overbreadth of liability resulting from adoption of that model would have to be redressed by adopting a "shopkeeper's privilege" as an affirmative defense separate from any mens rea requirement.
We use a longitudinal design to examine associations for a diverse sample of 2,120 Danish 16- to 30-month-old children between early expressive vocabulary and later reading and math outcomes in the sixth grade. Educational outcomes, in particular decoding and reading comprehension, can be predicted from an early vocabulary measure as early as 16 months with effect sizes (in proportion of variance accounted for) comparable to 1 year's mean growth in reading scores. The findings confirm in a relatively large population-based study that late talkers are at risk for low educational attainment because the majority of children experiencing early language delay obtain scores below average in measures of reading in the sixth grade. Low scores have the greatest predictive power, indicating that children with early delays have elevated risk for later reading problems.
Arsenic-doped GaN films and GaNAs films have been synthesized by MOCVD. Samples were grown on sapphire, GaN-coated sapphire, and GaAs substrates. Composition, structure, and phase distribution were characterized by EPMA, SIMS, XRD, and TEM. The arsenic content increases demonstrably as the growth temperature descreases from 1030 to 700 °C. In the high temperature limit, high quality arsenic-doped GaN forms on GaN-coated sapphire. In the low temperature regime, nitrogen-rich GaNAs forms under some growth conditions, with a maximum arsenic mole fraction of 3%, and phase segregation in the form of GaAs precipitates occurs with an increase in arsine pressure. Preferential formation of the nitrogen-rich phase on GaN-coated sapphire suggests the presence of substrate-induced “composition pulling”.
These IBA Rules on the Taking of Evidence in International Arbitration (‘IBA Rules of Evidence’) are a revised version of the IBA Rules on the Taking of Evidence in International Commercial Arbitration, prepared by a Working Party of the Arbitration Committee whose members are listed on pages i and ii.
The IBA issued these Rules as a resource to parties and to arbitrators to provide an efficient, economical and fair process for the taking of evidence in international arbitration. The Rules provide mechanisms for the presentation of documents, witnesses of fact and expert witnesses, inspections, as well as the conduct of evidentiary hearings. The Rules are designed to be used in conjunction with, and adopted together with, institutional, ad hoc or other rules or procedures governing international arbitrations. The IBA Rules of Evidence reflect procedures in use in many different legal systems, and they may be particularly useful when the parties come from different legal cultures.
Since their issuance in 1999, the IBA Rules on the Taking of Evidence in International Commercial Arbitration have gained wide acceptance within the international arbitral community. In 2008, a review process was initiated at the insistence of Sally Harpole and Pierre Bienvenu, the then Co-Chairs of the Arbitration Committee. The revised version of the IBA Rules of Evidence was developed by the members of the IBA Rules of Evidence Review Subcommittee, assisted by members of the 1999 Working Party. These revised Rules replace the IBA Rules on the Taking of Evidence in International Commercial Arbitration, which themselves replaced the IBA Supplementary Rules Governing the Presentation and Reception of Evidence in International Commercial Arbitration, issued in 1983.
Since their discovery carbon nanotubes have attracted much interest for their peculiar electronic properties which go from metalic to semiconducting behaviour, depending both on diameter and chirality. The exact vaue of their band gap is obviously a crucial point to be addressed because it enters in the nanotube application as microelectronic devices. By making use of an efficient GW scheme, previousy tested on bulk systems, as well as of a model screening function, we obtained for the first time excitation energies and band-gap vaues for carbon nanotubes. Results for (6,0) and (7,0) will be presented and discussed.
Selective interdiffusion of Al and Ga at AlxGa1−x As-GaAs heterointerfaces can be carried out by conventional masking procedures and diffusion of acceptor impurities (e.g., Zn), or donor impurities (e.g., Si), or also by ion implantation. This process, impurity-induced layer disordering (IILD), makes it possible to convert quantum well heterostructures (QWHs) such as AlxGa1−xAs-GaAs superlattices (SLs) into bulk homogeneous AlyGa1−yAs where y is the average Al composition of the QWH or SL. Since th IILY process is maskable and thus selective, heterojunctions can be formed in directions perpendicular to the crystal growth direction, i.e., between as-grown “ordered” and IILD “disordered” regions. To date this process has been used most effectively in the fabrication of buriedheterostructure QW lasers, single and multiple stripe, where the disordered regions provide both optical and electrical confinement. The IILD process has also been used to advantage in the fabrication of high power laser diodes with non-absorbing “windows” at the laser facets and thus with better immunity from facet damage. In this paper we present data on the application of the IILD process to the fabrication of buried-heterostructure QW laser diodes. We also describe possible mechanisms by which the impurity-induced layer disordering proceeds based on Column III “Frenkel” defects and the influence of the crystal Fermi level on the defect solubility. These mechanisms are supported by experimental data.
Exposure of GaAs and AlGaAs to a hydrogen plasma has been shown to result in a significant change in the electrical and optical properties. The changes are related to the electrical deactivation of the deep and shallow impurities by hydrogenation. Spectroscopic and electrical measurements have shown that Si donors and C acceptors in high purity GaAs can be passivated by hydrogenation. Hydrogenation of p-type GaAs and AlGaAs has resulted in highly resistive material. SiO2 was found to be a suitable mask for the hydrogenation process. Single and multiple stripe geometry lasers have been fabricated by properly masking the laser structure. The lasers produced using the hydrogenation process have low threshold currents and are capable of cw room temperature operation.
Non-uniform hot-carrier degradation in n-channel polycide-gate MOSFET's with different thicknesses of the poly-Si film, and in p-channel polycide-gate MOSFET's with TiSi2- or CoSi2-gate-silicide, is studied. The n-MOSFET's with the thinnest poly-Si film, show an increased interface trap generation, while the influence of the gate-silicide material on the degradation behaviour of the p-MOSFET's is found to be very small. The results are evaluated in terms of the effect of mechanical stress on the degradation characteristics: favourable for compressive mechanical stress and unfavourable for tensile stress. A correlation with stress measurements by micro-Raman spectroscopy is made.
Arsenic-doped GaN films and GaNAs films have been synthesized by MOCVD. Samples were grown on sapphire, GaN-coated sapphire, and GaAs substrates. Composition, structure, and phase distribution were characterized by EPMA, SIMS, XRD, and TEM. The arsenic content increases demonstrably as the growth temperature descreases from 1030 to 700°C. In the high temperature limit, high quality arsenic-doped GaN forms on GaN-coated sapphire. In the low temperature regime, nitrogen-rich GaNAs forms under some growth conditions, with a maximum arsenic mole fraction of 3%, and phase segregation in the form of GaAs precipitates occurs with an increase in arsine pressure, Preferential formation of the nitrogen-rich phase on GaN-coated sapphire suggests the presence of substrate-induced “composition pulling”.
The deposition kinetics of InP in MOCVD reactors is presented. The proposed chemical mechanism involves both gas phase and surface reactions. The fundamental hypothesis adopted in deriving the mechanism was a dual site dissociative adsorption of the precursors on the growing surface. In any case, all the rate constants either were taken from the literature or estimated through thermochemical methods. In addition, the deposition reactor was simulated by means of a monodimensional model that accounts for the main reactor features through the boundary layer theory.
We present an innovative-design heterostructure based on the exploitation of in-the-barrier piezoelectric field for all-optical light modulation. The novel layout allows an efficient light modulation with low power densities (few tens of W/cm2), easily attainable with standard laser diodes. The modulation mechanism relies upon drastic photocarrier separation by the piezoelectric field in the barrier layers. We present room temperature results showing that an optical “control” power of 70 W/cm2 creates in the heart of the structure a space-charge field of about 30 kV/cm, inducing large spectral shifts (∼100 nm) in the photoluminescence spectra of a CdHgTe quantum well in the 1.5 μm range.
In this work we employed lithographic techniques, combined with sputtering depositions, to fabricate semiconductor metal-oxide (MOX) gas sensors with controlled grain dimensions. The basic idea is to replace the continuous sensing film of standard MOX sensors with a pattern of wires in the sub-micron scale, thus controlling the lateral size of the grains. Regarding the fabrication process, we followed two different approaches: a plain lift-off technique and a substrate patterning process. We present a comparison between the results of both the approaches. Furthermore, we tested the electrical responses to several gases and compared them with those of continuous film sensors. The experimental data highlight an improvement for the patterned sensors.
Methacrylate-substituted tetranuclear tantalum, zirconium and titanium oxide clusters (Zr4O2(OMc)12, Ti4O2(OPri)6(OMc)6, and Ta4O4(OEt)8(OMc)4) were prepared by reaction of the alkoxides with methacrylic acid. The clusters were then polymerized with methyl methacrylate as co-monomers in different molar ratios (0.5–2 mol% of the functionalized cluster). In the resulting inorganic-organic hybrid polymers, the clusters crosslink the polymer chains very efficiently. The physical properties and structural features of the hybrid polymers, investigated by their swelling behavior, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), 13C MAS NMR and impedance spectroscopy, exhibit a clear dependence on the cluster portion in the polymer and on the cluster type.
Nanoscaled Iron Oxide / Silica Nanocomposite particles are produced in a pyrogenic process. The iron oxide crystallites are separated from each other and covered with a silica layer. Their size can easily be controlled by adjusting the process parameters. The amount of iron oxide can also be controlled within certain limits. Due to their size these isolated magnetic particles show a superparamagnetic behaviour. The saturation magnetisation measured depends almost linearly on the size of the iron oxide crystallites showing an increase in the magnetisation with increasing particle size. Due to the composite structure the iron oxide is chemically stable. Furthermore it shows a thermal stability which is unusual for the given oxides.
The integration of high-density CNT bundles as via interconnects in a CNT/Cu-hybrid BEOL stack is evaluated. CNT via-conduits may greatly improve heat dissipation and as such lower interconnect resistance and improve electromigration resistance. Each carbon shell of the nanotube contributes to electrical and thermal conduction and densities as high as 5×1013 shells per cm2 are estimated necessary. CNT growth processes on BEOL compatible metals are presented with tube densities up to 1012cm−2 and shell densities approaching 1013 cm−2 on blanket substrates. Selective growth of CNT bundles with carbon shell densities around 1012cm−2 is demonstrated with high yield. Ohmic behavior of TiN/CNT/Ti contacts is shown with a CNT via resistivity of 1.2 mΩ cm.
We conducted a study to acquire information on the current behavior of a sample of Italian surgeons and anesthesiologists about prescribing, interpreting, and using routine preoperative investigations. Consultants in surgery and anesthesiology in 60 hospitals in northern, central, and southern Italy were interviewed. Prescription of these procedures by doctors were driven more by personal experience than by updated scientific knowledge. This practice often led to ineffective and inefficient clinical practice, with healthy patients undergoing useless, time-consuming, costly, and sometimes harmful procedures.