The adsorption of Cr(III) was studied at pH 1, 2, 3, 4, 6, 8, and 10 on chlorite and kaolinite and at pH 1, 2, 3, and 6 on illite. The amount of chromium adsorbed on chlorite varied from 3.1 × 10–5 mole/ g at pH 1 to 16.6 × 10–5 mole/g at pH 4, and on illite from 4.9 × 10–5 mole/g to 9.2 × 10–5 mole/g at pH 1 and 3, respectively. Kaolinite adsorbed 3.7 × 10–5 mole Cr/g at pH 1, 2, and 3 and 5.5 × 10–5 mole Cr/g at pH 4. Measurements of the Cr 2p core-level binding energies indicate that chromium is probably adsorbed as a Cr(III) aqua ion at pH values below 4. The binding energies for the Cr 2p level for samples prepared above pH 4 compare favorably with the value determined for chromium hydroxide and lead to the conclusion that the chromium species present at pH 6, 8, and 10 is chromium hydroxide.

This study documents the contexts of platform pipe creation, distribution, and disposition at Illinois Havana Hopewell Tradition (50 BC to AD 200–250) sites to identify regional variation in Hopewell ceremonialism and exchange. We observe that the large deposits of stone pipes buried during communal rituals in the Scioto Valley and the continued influence of the Hopewell Sphere of Interaction have skewed archaeological interpretation. Aside from the several large deposits, pipes are limited in the Scioto Tradition and seldom found in habitation areas. In Illinois, pipe fabrication debris commonly occurs in habitation areas along with numerous examples of pipe repair and maintenance. Local pipestones—often from northern Illinois Sterling deposits—predominate, and exotic imported pipestones are unusual. Pipes are rare inclusions with individual burials as indicators of status, spiritual prowess, achievement, or group membership. The high value placed on pipes as communal sacra in Ohio and their value in Illinois as items of personal influence parallels their common occurrence in Illinois and their unique context in Ohio Hopewell. This study of the contexts of pipe manufacture and deposition reinforces current discussions of such artifact assemblages as important in documenting local variations in political, social, and religious mortuary ceremonialism across the “Hopewellian sphere.”

High-speed synchronized stereo particle-imaging velocimetry and OH planar laser-induced fluorescence (PIV/OH-PLIF) measurements are performed on multiple $R{-}\unicode[STIX]{x1D703}$ planes downstream of a high-Reynolds-number swirling jet. Dynamic-mode decomposition (DMD) – a frequency-resolved data-reduction technique – is used to identify and characterize recurrent flow structures. Illustrative results are presented in a swirling flow field for two cases – the nominal flow dynamics and where self-excited combustion driven oscillations provide strong axisymmetric narrowband forcing of the flow. The robust constituent of the nominal reacting swirl flow corresponds to a helical shear-layer disturbance at a Strouhal number ( $St$ ) of ${\sim}0.30$ , $St=fD/U_{0}$ , where $f$ , $D$ and $U_{0}$ denote the precessing vortex core (PVC) frequency ( ${\sim}800~\text{Hz}$ ), the swirler exit diameter (19 mm) and the bulk velocity at the swirler exit ( $50~\text{m}~\text{s}^{-1}$ ) respectively. Planar projections of the PVC reveal a pair of oscillating skew-symmetric regions of velocity, vorticity and OH-PLIF intensity that rotate in the same direction as the mean tangential flow. During combustion instabilities, the large-amplitude acoustics-induced axisymmetric forcing of the flow results in a fundamentally different flow response dominated by a nearly axisymmetric disturbance and almost complete suppression of the large-scale helical shear-layer disturbances dominating the nominal flow. In addition, reverse axial flows around the centreline are significantly reduced. Time traces of the robust constituent show reverse axial flows around the centreline and negative axial vorticity along the inner swirling shear layer when the planar velocity is in the same direction as the mean tangential flow. For both stable and unstable combustion, recurrent flow structures decay rapidly downstream of the air swirler, as revealed by the decreasing amplitude of the velocity, axial vorticity and OH-PLIF intensity.

Elongate canines evolved independently at least four times among mammalian carnivores, and each time skulls were modified in similar ways. We have compared the cranial morphology of sabertooths to that of their non-sabertoothed relatives, living and extinct, and applied simple biomechanical models to elucidate the functional significance of the morphological differences. Our analysis suggests that (1) sabertooth morphology represents modification for wider gape with retention of a powerful bite force at the carnassial; (2) sabertooths probably used a throat or ventral neck slash to kill prey; and (3) elongate canines and retractile claws may have facilitated the exploitation of relatively larger prey by sabertooths compared to non-sabertooth carnivores.

Evolutionary morphologists and paleontologists have long questioned whether there are general historical patterns to the distribution of morphological types. Few studies have rigorously addressed that question. This study tests the decoupling hypothesis, which predicts an increase in the number of morphological constraints with a reduction in the number of independent elements. Eight cases of historical transformation of the epicoracoid cartilages of frogs were selected for analysis. Similar morphological shape changes occurred across the independently derived historical transformations as determined by a triangle analysis of shape. These results support the decoupling hypothesis and indicate that there may be generalized historical pathways of structural change. This finding is important for the development of a predictive theory in evolutionary morphology.

Subsistence hunting can change the demographic structure of wild mammal populations, increasing the proportion of young animals, inducing females to reproduce early and increasing litter sizes. We examined the relationship between hunting pressure and age structure in the Vulnerable white-lipped peccary Tayassu pecari, analysing the distribution of age classes at seven sites in the region Terra do Meio in the Brazilian Amazon. These sites differ in the number of human inhabitants and hence were subject to differing hunting pressures. We completed semi-structured interviews with local people to assess the importance of hunting and of the white-lipped peccary as food. We also estimated the age of hunted white-lipped peccaries by assessing tooth eruption and tooth wear in skulls of hunted individuals. Our results indicated that the white-lipped peccary was the most frequently hunted terrestrial animal in the region. Fishing, followed by hunting, provided the main sources of animal protein. Our data suggest there is no relationship between age structure and hunting at the study sites. The social structure and mobility of white-lipped peccaries seem to minimize the effects of hunting on age structure. Our results, similar to previous studies, show that the age structure of the white-lipped peccary is robust to hunting impacts. Other factors may have stronger effects on age structure than subsistence hunting. We suggest that deforestation may explain the prevalence of older individuals in peccary populations to the north of our study sites.

The aim of this study was to evaluate the purine levels of lambs experimentally infected with Haemonchus contortus. A total of 12 healthy lambs were divided into two groups, composed of 6 animals each: Group A represented the healthy animals (uninfected), while in Group B the animals were infected with 15 000 larvae of H. contortus. Blood was drawn on days 15, 45 and 75 post-infection (PI) in order to perform the purine analysis (ATP, ADP, AMP, adenosine, inosine, hypoxanthine, xanthine and uric acid) by high pressure liquid chromatography (HPLC) in serum. On day 15 PI a significant (P<0·05) increase in the levels of ATP and inosine was observed in the infected animals, unlike the levels of ADP, adenosine, xanthine and uric acid which were reduced. On day 45 PI a significant (P<0·05) increase in the ATP and xanthine levels in infected animals was observed, contrasting with reduced levels of ADP and uric acid. Finally, on day 75 PI an increase occurred in the levels of ATP, adenosine and hypoxanthine in infected lambs, concomitant with a reduction in the levels of ADP and uric acid (P<0·05). These changes in purine levels may influence the inflammatory process and the pathological events.

The Magellanic System represents one of the best places to study the formation and evolution of galaxies. Photometric surveys of various depths, areas and wavelengths have had a significant impact on our understanding of the system; however, a complete picture is still lacking. VMC (the VISTA near-infrared YJK s survey of the Magellanic System) will provide new data to derive the spatially resolved star formation history and to construct a three-dimensional map of the system. These data combined with those from other ongoing and planned surveys will give us an absolutely unique view of the system opening up the doors to truly new science!

Mary W. Helms’s observation that spatial distance often correlates with spiritual power has become an axiom in interpreting the role of exotic materials in societies. This is especially evident in explanations of the North American Hopewell Interaction Sphere. The circulation and accumulation of exotic materials in massive mortuary caches peaked during the Hopewell era (100 B.C. to A.D. 300). The premise that Hopewell smoking pipes were made in Ohio, primarily of local raw material, and circulated to foreign locations was an integral part of this interaction model. In this study we demonstrate, primarily using reflectance near-infrared spectroscopy (NIS), that early Hopewell Tremper Mound pipe raw-material acquisition focused on exotic pipestones from Illinois and Minnesota. By contrast, later Mound City cache pipes were almost exclusively made from local limestone and pipestone. The discovery of this shift in preference for and/or access to different quarry sources by Ohio Hopewell societies provides new perspectives on early Hopewell development and long-distance interaction.

In this article, the sol-gel methodology was used for coating an acrylonitrile butadiene styrene (ABS) polymer prepared by the rapid prototyping technology with a colloid containing the europium III dipicolinic complex, which presents high emission when excited in the ultraviolet region. Either acid or base was used for treatment of the ABS polymer, with a view to activating its surface. The thermal analysis evidenced a residual mass after 600 °C, which indicated that the coating adhered to the substrate. X-ray diffraction analysis showed that the structure of the ABS polymer was not affected by the sol-gel treatment. The large band centered at 287 nm, ascribed to ligand-metal charge transfer, can be used to excite the europium III dipicolinic complex in the ultraviolet C and ultraviolet B regions. The emission appears in the characteristic red region of the electromagnetic spectrum. These results indicate that the obtained material is a candidate for use as ultraviolet sensor.

The tick Rhipicephalus (Boophilus) microplus is an important parasite of cattle in many areas of the tropics. Characterization of molecules involved in mechanisms such as vitellogenesis and embryo development may contribute to a better understanding of this parasite's physiology. The vitellin-degrading cysteine endopeptidase (VTDCE) is the most active enzyme involved in vitellin hydrolysis in R. microplus eggs. Here we show an association between VTDCE and vitellin in an additional site, apart from the active site. Our data also demonstrate cysteine endopeptidase activity in different tissues such as ovary, gut, fat body, salivary gland and female haemolymph, where it is controlled by a physiological inhibitor. In R. microplus female gut, VTDCE is localized in areas of protein synthesis and trafficking with the underlying haemolymph. VTDCE is also localized in the ovary basal region, in vesicle membranes of ovary pedicel cells and in oocyte cytosol. These results suggest that VTDCE plays a role in vitellin digestion during tick development.

A novel Differential Hall Effect technique is used to obtain doping profiles of 2keV implants of antimony in <100> silicon at a depth resolution of 2nm. The electrical profiles are compared with atomic profiles determined from Secondary Ion Mass Spectroscopy (SIMS) measurements. We demonstrate good consistency between the two profiling techniques and confirm that the SIMS profiles can be used to identify the junction depth. The profiles show that antimony does not diffuse significantly for annealing temperatures below 800°C.

The anuran lower jaw is composed of three pairs of bones: dentaries, angulosplenials and mentomeckelians. Although the lower jaw is toothless, except in Gastrotheca guentheri, enlarged fangs or odontoids have evolved at least four times independently in some myobatrachids, hylids, ranids and leptodactylids through both parallel and convergent evolutionary events. Fangs seem to represent the single best design solution to enable an anuran to inflict a bite-like wound, but the biological role of biting varies among species. Fangs are projections of the dentaries in ranids, but in the hylid frog Hemiphractus and in ceratophryine leptodactylids, they form a sinosteotic unit with the dentaries and mentomeckelians. Comparisons of morphology, behaviour and diet among frog taxa with enlarged fangs reveal that the fangs may be the result of either sexual or natural selection. Those fangs that evolved in response to sexual selection seem to be relatively larger than those that resulted of natural selection.

The first relative sensitivity factors (RSF) for detecting the major and dopant elements of optical materials by ultrahigh intensity post-ionization (UHIPI) mass spectrometry are determined. The post-ionization is performed using a single laser wavelength with intensities greater than 1014 W/cm2. Zn-implanted InP and In0.4Ga0.1As0.3P0.2 are used to investigate the photoionization of sputtered atoms and molecules. Under optimal conditions, the UHIPI RSF's for atomic singly charged In, Ga, and Zn are nearly equal; that is, the ratio of UHIPI signals is equal to the concentration ratio. In principle, no standards are needed for quantitative analysis. Arsenic and P, with higher ionization potentials, are not detected as efficiently as other elements. The detected mass balance is usually group III rich. An entire mass spectrum is necessary for complete characterization of all elements and adjustment of their RSF's because many sputtered molecules are detected containing the group V elements. Multiply charged species compose about 10% of the detected ions.

Many semiconductor processes, Organometallic Vapor Phase Epitaxy (OMVPE) in this case, require the use of concentrated hydride sources. The toxicity of many of these compounds (e.g. arsine, diborane) and the pyrophoric nature of others (phosphine and silane) demand that the facility provide both environmental protection and a safe work place. A facility is described which meets stringent environmental emission standards from NY State's Department of Environmental Conservation. The outlined approach also sets new standards for hydride storage and containment, laboratory alarm systems, exhaust gas treatment and dilution, and process integration into the facility. Under normal operation, we demonstrate hydride emissions of less than 10−5 ppb at the exhaust stack.

We contrast the stability under bias-aging conditions of GaAs/AlGaAs HBTs utilizing highly Be- or C-doped base layers. Devices with Be doping display a rapid degradation of dc current gain and junction ideality factor. At 200°C, a 2 × 10 μm2 Be-doped device (4 × 1019cm−3 base doping) operated at a current density of 2.5 × 104 A. cm−2 shows a decrease in gain from 16 to 1.5 within 2h. Under the same conditions a C-doped device with even higher base-doping (7 × 1019 cm−3) is stable over periods of 36h, the longest time we tested our structures. The degradation of Be-doped devices is consistent with the mechanism of recombination-enhanced diffusion of interstitials into the adjoining layers. Similar results are obtained with Zn-doped devices. Since C occupies the As sub-lattice rather than the Ga sublattice as with Be and Zn, it is not susceptible to reaction with Ga interstitials injected during growth or bias-aging.