Guinea pigs (Cavia spp.) have a long association with humans. From as early as 10,000 years ago they were a wild food source. Later, domesticated Cavia porcellus were dispersed well beyond their ...native range through pre-Columbian exchange networks and, more recently, widely across the globe. Here we present 46 complete mitogenomes of archaeological guinea pigs from sites in Peru, Bolivia, Colombia, the Caribbean, Belgium and the United States to elucidate their evolutionary history, origins and paths of dispersal. Our results indicate an independent centre of domestication of Cavia in the eastern Colombian Highlands. We identify a Peruvian origin for the initial introduction of domesticated guinea pigs (Cavia porcellus) beyond South America into the Caribbean. We also demonstrate that Peru was the probable source of the earliest known guinea pigs transported, as part of the exotic pet trade, to both Europe and the southeastern United States. Finally, we identify a modern reintroduction of guinea pigs to Puerto Rico, where local inhabitants use them for food. This research demonstrates that the natural and cultural history of guinea pigs is more complex than previously known and has implications for other studies regarding regional to global-scale studies of mammal domestication, translocation, and distribution.
•Coated high voltage porcelain bushings were tested under high-velocity impact.•Pressurized borosilicate glass cylinders were also investigated under impact for cascading effects.•Efficiency of ...elastomeric coating on ballistic damage in the bushings and cylinders was investigated.•Elastomeric coatings can prevent impact damage to the bushings and cylinders under rifle impact.
This paper contributes further to the discussion recently initiated in Ref. 1 regarding the protection of pressurized porcelain bushings against high-velocity impacts on high-voltage (HV) transformers by means of an elastomeric coating. Valuable observations and conclusions were made in our previous work concerning the impact behavior of the bushings and their protection from a unique combination of ballistic air gun tests performed on borosilicate glass cylinders, representing the bushings, and from flat glass plates tested via drop tower. Clearly, the conclusions from our previous work, critical to many utilities world-wide, needed to be independently verified by full-scale ballistic testing performed on the actual bushings under rifle bullet impact. In addition, to complete the impact analysis, the coated borosilicate cylinders were subjected to impact at energies higher than an air gun to demonstrate the energy effect on cylinder failure. Also, the cascading failures of the cylinders was investigated in this work, for the first time, to show what a single unprotected bushing failure could do to surrounding infrastructure. It was shown that the cascading failure of pressurized unprotected bushings could be a real and dangerous threat in a substation. It was also found that the linear extrapolations of fragmentation behavior with respect to energy in 1 is misleading. Most importantly, the unique but slightly speculative predictions of coating protections on the bushings were significantly overestimated, which was clearly demonstrated in this work. The bushings could be protected by an elastomeric coating against rifle bullet impacts with a coating thickness of a few mm instead of 60 mm as previously reported.
The archaeological site of Quebrada Tacahuay, Peru, dates to 12,700 to 12,500 calibrated years before the present (10,770 to 10,530 carbon-14 years before the present). It contains some of the oldest ...evidence of maritime-based economic activity in the New World. Recovered materials include a hearth, lithic cutting tools and flakes, and abundant processed marine fauna, primarily seabirds and fish. Sediments below and above the occupation layer were probably generated by El Niñno events, indicating that El Nino was active during the Pleistocene as well as during the early and middle Holocene.
•Pressurized borosilicate glass cylinders were tested under high-velocity impact.•Efficiency of elastomeric coating on ballistic damage was investigated.•Drop tower testing was added to verify air ...gun results on the cylinders.•Critical coating thicknesses to prevent initiation of ballistic damage to porcelain bushings was estimated.
Pressurized borosilicate glass cylinders were used to (1) simulate experimentally high-voltage transformer bushing behavior under high-velocity impact from an air gun, (2) investigate fragment dynamics to estimate the impact range of airborne fragments, and (3) evaluate the efficiency of an elastomeric coating on ballistic damage initiation and fragment confinement. Using high-speed cameras, the velocities and directions of ejected fragments from the cylinders were determined along with fragment distribution symmetry. Drop tower testing was added to independently verify the air gun results on the cylinders through a different test under similar impact energies using flat samples of the same glass. Elastomeric coatings were also applied to both the cylinders and flat samples to increase their resistance to high energy impact. It has been shown that internal pressure in the glass cylinders plays a major role in the failure modes during high-velocity impacts. This pressure affects velocities, directions, and symmetry of fragment distribution. The fragment impact range investigation turned out to be inconclusive due to highly erratic behavior of the fragments after the blast. Most importantly, it has been ascertained that fragment dynamics are drastically altered by elastomeric coatings, producing a high level of fragment confinement both in the drop tower and gun tests. By extrapolating the air gun and drop tower data out to high power rifle energy levels, unique predictions of the critical coating thicknesses to prevent the initiation of ballistic damage and to confine fragments in borosilicate glass cylinders and C-120 porcelain bushings were achieved for the first time.
Sulfonated manganese and iron porphyrins have been used as catalysts in attempts to mimick the oxidation of acetaminophen and two ellipticine derivatives by horseradish peroxidase. Cofactors were ...potassium monopersulfate for the synthetic catalyst and hydrogen peroxide for the natural enzyme. Hindered metalloporphyrins, i.e. with ortho positions of the meso-phenyl rings substituted with methyl groups iron(III) and manganese(III) derivatives of octasodium mesotetrakis(3,5-disulfonatomesityl)porphyrin, were shown to be at least 10 times more robust than unsubstituted derivatives iron(III) and manganese(III) derivatives of tetrasodium meso-tetrakis(4-sulfonatophenyl)porphyrin when activated in the absence of substrate. The catalytic activity depends on the nature of the substrate as shown by a decrease or an increase in reactivity observed, respectively, in the oxidation of acetaminophen or ellipticine derivatives catalyzed by hindered metalloporphyrins compared with nonhindered ones. Only sterically hindered metalloporphyrins, even in the case of lowered reactivity, were allowed to mimick the behavior of horseradish peroxidase when activated in the absence of substrate (stability toward autodegradation) and in the course of repeated infusion of substrate (retained catalytic activity as time advances).
Before the Inca reigned, two empires held sway over the central Andes from anno Domini 600 to 1000: the Wari empire to the north ruled much of Peru, and Tiwanaku to the south reigned in Bolivia. ...Face-to-face contact came when both colonized the Moquegua Valley sierra in southern Peru. The state-sponsored Wari incursion, described here, entailed large-scale agrarian reclamation to sustain the occupation of two hills and the adjacent high mesa of Cerro Baúl. Monumental buildings were erected atop the mesa to serve an embassy-like delegation of nobles and attendant personnel that endured for centuries. Final evacuation of the Baúl enclave was accompanied by elaborate ceremonies with brewing, drinking, feasting, vessel smashing, and building burning.
Animals in complex human societies are often both meal and symbol, related to everyday practice and ritual. People in such societies may be characterized as having unequal access to such resources, ...or else the meaning of animals may differ for component groups. Here, in this book, 28 peer-reviewed papers that span 4 continents and the Caribbean islands explore in different ways how animals were incorporated into the diets and religions of many unique societies. The temporal range is from the Neolithic to the Spanish colonization of the New World as well as to modern tourist trade in indigenous animal art. The volume explores various themes including the interaction of foodways with complex societies, the interaction between diet and colonialism and the complex role that animals, and parts of animals, play in all human societies as religious, identity markers, or other types of symbols. Organized according to these themes, rather than geographic location or time period, the papers presented here crosscut such divisions. In so doing, this book presents an opportunity for scholars divided by geography especially, but also by temporal period, to explore each other's research and demonstrate that different archaeological settings can address the same problems cross-culturally.
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