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A distinct feature of many of the earliest archaeological sites (13,000-11,200 cal yr BP) at the core of the Atacama Desert is that they lie at or just below the surface, often encased in desert pavements. In this study, we compare these sites and undisturbed desert pavements to understand archaeological site formation and pavement development and recovery. Our results indicate these pavements and their soils are poorly developed regardless of their age. We propose that this is because of sustained lack of rain and extreme physical breakdown of clasts by salt expansion. Thus, the core of the Atacama provides an example of the lower limits of rainfall (<50 mm/yr) needed to form desert pavements. At site Quebrada Maní 12 (QM12), humans destroyed the pavement. After abandonment, human-made depressions were filled with eolian sands, incorporating artifacts in shallow deposits. Small and medium-sized artifacts preferentially migrated upwards, perhaps due to earthquakes and the action of salts. These artifacts, which now form palimpsests at the surface, helped – along with older clasts - to restore surface clast cover. Larger archaeological features remained undisturbed on top of a deeper Byzm horizon. The vesicular A horizons (Av horizons) have not regenerated on the archaeological sites due to extreme scarcity of rainfall during the Holocene.
A key concern regarding current and future climate change is the possibility of sustained droughts that can have profound impacts on societies. As such, multiple paleoclimatic proxies are needed to identify megadroughts, the synoptic climatology responsible for these droughts, and their impacts on past and future societies. In the hyperarid Atacama Desert of northern Chile, many streams are characterized by perennial flow and support dense in-stream wetlands. These streams possess sequences of wetland deposits as fluvial terraces that record past changes in the water table. We mapped and radiocarbon dated a well-preserved sequence of in-stream wetland deposits along a 4.3-km reach of the Río San Salvador in the Calama basin to determine the relationship between regional climate change and the incision of in-stream wetlands. The Río San Salvador supported dense wetlands from 11.1 to 9.8, 6.4 to 3.5, 2.8 to 1.3, and 1.0 to 0.5 ka and incised at the end of each of these intervals. Comparison with other in-stream wetland sequences in the Atacama Desert, and with regional paleoclimatic archives, indicates that in-stream wetlands responded similarly to climatic changes by incising during periods of extended drought at ~9.8, 3.5, 1.3, and 0.5 ka.
The Kabwe Zn-Pb deposit (central Zambia) consists of a cluster of mixed sulfide and non-sulfide orebodies. The sulfide ores comprise sphalerite, galena, pyrite, chalcopyrite and accessory Ge-sulfides (±Ga and In). The non-sulfide ores comprise: (1) willemite-dominated zones encasing massive sulfide orebodies and (2) oxide-dominated alteration bands, overlying both the sulfide and Zn-silicate orebodies. This study focuses on the Ge, In and Ga distribution in the non-sulfide mineralization, and was carried out on a suite of Kabwe specimens, housed in the Natural History Museum Ore Collection (London). Petrography confirmed that the original sulfides were overprinted by at least two contrasting oxidation stages dominated by the formation of willemite (W1 and W2), and a further event characterized by weathering-related processes. Oxygen isotopic analyses have shown that W1 and W2 are unrelated genetically and furthermore not related to supergene Zn-Pb-carbonates in the oxide-dominated assemblage. The δ18O composition of 13.9–15.7‰ V-SMOW strongly supports a hydrothermal origin for W1. The δ18O composition of W2 (−3.5‰ to 0‰ V-SMOW) indicates that it precipitated from groundwaters of meteoric origin in either a supergene or a low-T hydrothermal environment. Gallium and Ge show a diversity of distribution among the range of Zn-bearing minerals. Gallium has been detected at the ppm level in W1, sphalerite, goethite and hematite. Germanium occurs at ppm levels in W1 and W2, and in scarcely detectable amounts in hemimorphite, goethite and hematite. Indium has low concentrations in goethite and hematite. These different deportments among the various phases are probably due to the different initial Ga, In and Ge abundances in the mineralization, to the different solubilities of the three elements at different temperatures and pH values, and finally to their variable affinities with the various minerals formed.
Head and neck space infections present with a potential mortality rate of 40–50 per cent. This paper proposes an algorithm-based management of head and neck space infection to prevent life-threatening events.
Methods:
A total of 225 patients with head and neck space infection were prospectively analysed at our institution. An experimental scoring system determined the level of clinical risk for the development of major complications. Accordingly, patients were classified into three risk groups: low-, intermediate- and high-risk.
Results:
Only intermediate- and high-risk patients were hospitalised. Intermediate-risk patients received intravenous medical therapy with daily re-evaluation; 18 of them required delayed surgery. Of the high-risk patients, three required immediate surgical treatment and five received delayed surgery, while in five cases medical therapy was the only treatment received. Low-risk patients were treated in an out-patient setting.
Conclusion:
The algorithm-based management of head and neck space infection was successful in enabling the avoidance of lethal complications onset.
Hunter-gatherers collected and used various woody species depending on the landscape, availability of plant communities, and sociocultural considerations. With extensive paleo-wetlands and groundwater-fed oases, the Atacama Desert was interspersed with riparian woodlands that provided vital resources (fuel, water, and game) at the end of the Pleistocene in areas such as the Pampa del Tamarugal (PdT) basin. We use anthracological analyses to determine the fuel management strategies of hunter-gatherer societies in this hyperarid environment and explore whether the “Principle of Least Effort” applies. First, we present the combustion qualities and characteristics of woody taxa from the Atacama and analyze possible exploitation strategies. Second, we use anthracological analyses from Quebrada Maní 12 (QM12), a late Pleistocene archaeological site (dated from 12,750 to 11,530 cal B.P.) located in the PdT basin, to show the prevalence of two woody species that were either freshly collected or gathered (very likely on purpose) from subfossil wood. Our results suggest that fuel selection strategies were based on prior knowledge of the qualities of these woody taxa and how they burned. Thus we conclude that fuel management was part of a number of social and economic decisions that allowed for effective colonization of this region. Furthermore, we stress the need for caution when using charcoal to exclusively date archaeological sites located in desert environments.
The air sacs of free-ranging birds of prey (n= 652) from southern Italy, including 11 species of Accipitriformes and six of Falconiforms, were examined for infections with Serratospiculumtendo (Nematoda: Diplotriaenoidea). Of the 17 species of birds examined, 25 of 31 (80.6%) peregrine falcons (Falco peregrinus) from Calabria Region and a single northern goshawk (Accipiter gentilis) from Campania Region were infected with S. tendo, suggesting a strong host specificity for the peregrine falcon. The northern goshawk and 18 of 25 infected peregrine falcons showed cachexia and all infected birds had bone fractures. At gross examination, air sacculitis and pneumonia were the most common lesions in infected birds. Microscopically, the air-sac walls showed thickening of the smooth muscle cells, resulting in a papillary appearance, along with hyperplasia of the mesothelium and epithelium, and foci of plasma cell infiltration and macrophages associated with several embryonated eggs and adult parasites. Extensive areas of inflammation were found in the lungs, characterized by lymphocytes, macrophages and fibroblasts surrounding embryonated eggs. The northern goshawk also had detachment of the dextral lung with several necrotic foci. In this case, the death of the bird was directly attributed to S. tendo infection. Lesions and pathological changes observed here suggest that S. tendo can cause disease.
Exercise has been shown to increase mRNA expression of a growing number of genes. The aim of this study was to assess if mRNA expression of the metabolism- and oxidative stress-related genes GLUT4 (glucose transporter 4), COX2 (cyclooxygenase 2), SOD1 (superoxide dismutase 1) and HSP70 (heat shock protein 70) in saliva changes following acute exercise stress in dogs. For this purpose, 12 avalanche dogs of the Italian Military Force Guardia di Finanza were monitored during simulation of a search for a buried person in an artificial avalanche area. Rectal temperature (RT) and saliva samples were collected the day before the trial (T0), immediately after the descent from a helicopter at the onset of a simulated avalanche search and rescue operation (T1), after the discovery of the buried person (T2) and 2 h later (T3). Expressions of GLUT4, SOD1, COX2 and HSP70 were measured by real-time PCR. The simulated avalanche search and rescue operation was shown to exert a significant effect on RT, as well as on the expression of all metabolism- and oxidative stress-related genes investigated, which peaked at T2. The observed expression patterns indicate an acute exercise stress-induced upregulation, as confirmed by the reductions in expression at T3. Moreover, our findings indicate that saliva is useful for assessing metabolism- and oxidative stress-related genes without the need for restraint, which could affect working dog performance.
We discuss Chinchorro mortuary practices during the Middle Archaic (7000-5000 B.P.) as demonstrated by 12 funerary contexts excavated at the site of Maestranza Chinchorro, northern Chile. First we describe each of the funerary contexts. Then we discuss the variability of mortuary practices, the configuration of multiple burials, the mortuary treatment of human fetuses, lifestyle, and paleopathology. We conclude that mortuary practices are heterogeneous and that not all subjects received elaborate treatment. Mortuary ritual focused on the seven infants in the group, which included two fetuses of a few months' gestation, something fairly unusual in human prehistory. Treatment consisted in the removal of all soft tissue and the use of sticks to reinforce the skeletons, upon which abundant gray clay was mounted in order to model the human figure. In contrast to the infants, just one young adult woman received complex mortuary treatment. Finally, based on the spatial distribution of contemporary burial sites, we propose that Middle Archaic communities in coastal Arica comprised small groups, including adults and children of different sexes, that settled around key resources like watering holes, rivers, wetlands, and hunting and fishing areas. This resulted in fierce intergroup competition and highly territorial behavior.
A study on the axisymmetric near-contact motion of drops with tangentially mobile interfaces under the action of a body force in a quiescent fluid is described. A long-time asymptotic analysis is presented for small-deformation conditions. Under these conditions the drops are nearly spherical, except in the near-contact region, where a flattened thin film forms. According to our analysis, a hydrostatic dome does not form in the near-contact region at long times, in contrast to the assumption underlying all previous analyses of this problem. Instead, the shape of the film in the near-contact region results from the absence of tangential stresses acting on it. As a result, the long-time behaviour of the system is qualitatively different than previously predicted. According to the theory presented herein, the minimum film thickness (rim region) decays with time as
${h}_{m} \sim {t}^{- 4/ 5} $
, and the thickness at the centre of the film decays as
${h}_{0} \sim {t}^{- 3/ 5} $
, which is a faster decay than predicted by prior analyses based on a hydrostatic dome. Numerical thin-film simulations quantitatively confirm the predictions of our small-deformation theory. Boundary-integral simulations of the full two-drop problem suggest that the theory also describes qualitatively the long-time evolution under finite-deformation conditions.
Parasite assemblages of the Western whip snake Hierophis viridiflavus carbonarius were investigated from the Calabria region in southern Italy. A total of 14 parasite taxa including 6 nematodes, 3 acanthocephalans, 2 cestodes, 2 digeneans and a single pentastomid was identified. Within the study area, H. v. carbonarius serves as the final host for seven species of helminths, of which only four (Hexametra quadricornis, Kalicephalus viperae, Paracapillaria sonsinoi and Renifer aniarum) can be considered as snake specialists, while one (Oswaldocruzia filiformis) is shared with other reptiles and amphibians, and two (Paradistomum mutabile and Rhabdias fuscovenosa) with lizards. A large proportion of larval forms of six helminth taxa (about 95% of all helminths collected) was found, for which H. v. carbonarius serves as an intermediate and/or paratenic host; however, adult stages of helminths were prevalent in snakes with snout-to-vent length greater than 70 cm. Our results suggest that ontogenetic and ecological factors should exert a strong influence upon the helminth assemblage of Western whip snakes. We concluded that H. v. carbonarius plays an important role in southern Italy as an intermediate/paratenic host for species of helminths infecting vertebrate groups which may include this snake species within their feeding chain. Eleven taxa, including three potential agents of zoonosis, were added to the poorly known parasite fauna of this host.
Animal models of anxiety disorders emphasize the crucial role of locus ceruleus–noradrenergic (norepinephrine, NE) signaling, the basolateral amygdala (BLA) and their interactions in the expression of anxiety-like behavioral responses to stress. Despite clinical evidence for the efficacy of a β-noradrenergic receptor blockade with propranolol in the alleviation of anxiety symptoms and the secondary prevention of post traumatic stress disorder, preclinical evidence for a β-noradrenergic modulation of BLA activity in humans is missing.
Method
We combined functional magnetic resonance imaging in healthy volunteers with probabilistic mapping of intra-amygdalar responses to fearful, neutral and happy facial expressions to test the hypothesis that a β-noradrenergic receptor blockade with propranolol would inactivate the BLA.
Results
Consistent with our a priori hypothesis, propranolol diminished BLA responses to facial expressions, independent of their emotional valence. The absence of activity changes in probabilistically defined visual control regions underscores the specific action of propranolol in the BLA.
Conclusions
Our findings provide the missing link between the anxiolytic potential of propranolol and the biological basis of β-noradrenergic activation in the human BLA as a key target for the pharmacological inhibition of anxiety neurocircuitry. Moreover, our findings add to emerging evidence that NE modulates both the reactivity (sensitivity) and the operating characteristics (specificity) of the BLA via β-noradrenergic receptors.
This study analyses the anti-proliferative effect of lemongrass essential oil and its main constituent (citral) on all 3 evolutive forms of Trypanosoma cruzi. Steam distillation was used to obtain lemongrass essential oil, with chemical composition determined by gas chromatography (GC) and GC coupled to mass spectrometry (GC-MS). The IC50/24 h (concentration that reduced the parasite population by 50%) of the oil and of citral upon T. cruzi was determined by cell counting in a Neubauer chamber, while morphological alterations were visualized by scanning and transmission electron microscopy. Treatment with the essential oil resulted in epimastigote growth inhibition with IC50=126·5 μg/ml, while the IC50 for trypomastigote lysis was 15·5 μg/ml. The IC50/48 h for the Association Index (% macrophage infection×number of amastigotes per cell) was 5·1 μg/ml, with a strong inhibition of intracellular amastigote proliferation. Ultrastructural analysis demonstrated cytoplasmic and nuclear extraction, while the plasma membrane remained morphologically preserved. Our data show that lemongrass essential oil is effective against T. cruzi trypomastigotes and amastigotes, and that its main component, citral, is responsible for the trypanocidal activity. These results indicate that essential oils can be promising anti-parasitic agents, opening perspectives to the discovery of more effective drugs of vegetal origin for treatment of parasitic diseases. However, additional cytotoxicity experiments on different cell lines and tests in a T. cruzi-mouse model are needed to support these data.
Auditory neuropathy (AN) is a hearing disorder characterized by the absence or severe distortion of the auditory brainstem responses, in the presence of preserved otoacoustic emissions. This peculiar combination suggests the presence of a defect impinging upon the functional complex formed by inner hair cells, the primary afferents (spiral ganglion neurones) and the first order synapses between hair cells and the cochlear nerve. Typically, AN patients show a severe speech perception impairment, which appears reduced out of proportion to pure tone threshold, but the clinical presentation of AN is quite complex.
Hearing loss is a common symptom associated with mitochondrial diseases; however, AN has only rarely been reported in these disorders.
Here we report a rare association, the first case observed in Italy, in a patient with autosomal recessive mitochondrial myopathy and mitochondrial DNA multiple deletions, and a hearing deficit with the audiological and electrophysiological features of AN.
Limb girdle muscular dystrophy 2A (LGMD2A), caused by calpain 3 deficiency, is currently diagnosed through the immunodetection of muscle protein by Western blot (WB) analysis . However, WB may provide normal results in patients with LGMD2A. The case of a female (3y 6mo of age) is described. She was found to be affected by asymptomatic hypercreatine-kinaesaemia during routine biochemical analysis at 10 months of age and had developed myopathic signs at the last neurological assessment. The WB of muscle biopsy performed at 28 months of age showed a normal quantity and pattern of bands for calpain 3. Despite this finding, on molecular analysis she was found to be a compound heterozygote for two mutations of the calpain 3 (CAPN3) gene (R110X and G222R). Autocatalytic activity assay showed a loss of function of calpain 3. This is the first genetically confirmed case of very early onset calpainopathy with a normal amount of protein at WB. Molecular analysis is also suggested in very young patients with normal WB.