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The occupation history of the Cahokia archaeological complex (ca. AD 1050–1400) has received significant academic attention for decades, but the subsequent repopulation of the region by indigenous peoples is poorly understood. This study presents demographic trends from a fecal stanol population reconstruction of Horseshoe Lake, Illinois, along with information from archaeological, historical, and environmental sources to provide an interpretation of post-Mississippian population change in the Cahokia region. Fecal stanol data indicate that the Cahokia region reached a population minimum by approximately AD 1400, regional population had rebounded by AD 1500, a population maximum was reached by AD 1650, and population declined again by AD 1700. The indigenous repopulation of the area coincides with environmental changes conducive to maize-based agriculture and bison-hunting subsistence practices of the Illinois Confederation. The subsequent regional depopulation corresponds to a complicated period of warfare, epidemic disease, Christianization, population movement, and environmental change in the eighteenth century. The recognition of a post-Mississippian indigenous population helps shape a narrative of Native American persistence over Native American disappearance.

Northern Vietnam has a long history of human occupation, warfare, and agriculture; yet, the environmental consequences of human activity are poorly understood due to limited paleoecological records. Results from a terrestrial wetland sediment core from the tropical island, Quan Lan, in Ha Long Bay provide a local record of ecosystem responses to societal shifts due to warfare/instability and climate change. A multiproxy study, including pollen, macro charcoal, fecal stanols, and geochemistry, suggests that native vegetation was abundant and low-level, subsistence wet-rice agriculture and burning were in practice during a time of increased monsoon intensity between 1150 BCE and 950 CE. Between 950 and 1450 CE, a trading and military port was established on Quan Lan Island which served as a major hub of southeast Asian trade and protected the mainland from Mongol invasions. During this period, population near the wetland declined to undetectable levels, rice agriculture declined, burning ceased, and disturbance species expanded. A simultaneous shift toward a more arid climate, with possible extended years of drought, occurred during the Medieval Climate Anomaly based on regional climate records. Without a reliable source of freshwater, rice production declined and/or was supplemented by trade. When the mainland capital near present day Hanoi moved south to Hue after 1450 CE, the port ceased operation. During this time, climate became wetter, and precipitation and surface water more reliable than before. Population near the wetland increased as did burning and rice agriculture. The research has implications for understanding the maintenance of tropical biodiversity amidst long-term human occupation, political unrest, and climate change.

A number of competing hypotheses, including hydroclimatic variations, environmental degradation and disturbance, and sociopolitical disintegration, have emerged to explain the dissolution of Cahokia, the largest prehistoric population center in the United States. Because it is likely that Cahokia's decline was precipitated by multiple factors, some environmental and some societal, a robust understanding of this phenomenon will require multiple lines of evidence along with a refined chronology. Here, we use fecal stanol data from Horseshoe Lake, Illinois, as a population proxy for Cahokia and the broader Horseshoe Lake watershed. We directly compare the fecal stanol data with oxygen stable-isotope and paleoenvironmental data from the same sediment cores to evaluate the role of flooding, drought, and environmental degradation in Cahokia's demographic decline and sociopolitical reorganization. We find that Mississippi River flooding and warm season droughts detrimental to agriculture occurred circa (ca.) 1150 CE and possibly generated significant stress for Cahokia's inhabitants. Our findings implicate climate change during the Medieval Climatic Anomaly to Little Ice Age transition as an important component of population and sociopolitical transformations at Cahokia, and demonstrate how climate transitions can simultaneously influence multiple environmental processes to produce significant challenges to society.

Highlights • Conservative management alone, in certain cases, can be an effective method of treating large cerebral abscesses that would normally warrant surgical intervention in patients with complex congenital heart conditions. • Having an alternative, non-surgical, method of treating large brain abscesses in patients with underlying complex congenital heart conditions, in which brain abscesses is a known complication, is of great clinical importance. • Due to the increasing number of patients living longer with congenital heart conditions, further study into the conservative management of larger abscesses is warranted., Introduction We present an unusual case where a large intra-cerebral abscess with severe complications was treated successfully with medical management alone in a patient with Eisenmenger syndrome. Presentation of case A 40 year old patient with Eisenmenger syndrome presented with a seven day history of headache, neck pain and intermittent vomiting and fever. The only neurological examination finding was blurred vision. MRI revealed a large left occipital lobe abscess, which subsequently ruptured into the lateral ventricle with associated ventriculitis and hydrocephalus. This complicated abscess was successfully treated with intravenous antibiotics alone, with complete resolution of the abscess and hydrocephalus on MRI at 13 months post-diagnosis. Discussion Patients with congenital cyanotic heart conditions, like Eisenmenger syndrome, are at increased risk of developing intra-cerebral abscesses. Effectively managing large abscesses with associated intra-ventricular rupture and hydrocephalus in these patients without any form of surgical intervention, including aspiration, is extremely rare. Conclusion Patients with congenital cyanotic heart disease who develop large intra-cerebral abscesses with severe complications, which would normally warrant surgical intervention, have the potential to be successfully treated with antibiotics alone with excellent outcome.

Most seed predation studies focus on either pre- or post-dispersal predation and may therefore underestimate the role of predation in regulating plant populations. We therefore estimated total seed predation of an invasive tree, mesquite (Leguminoseae: Prosopis spp.), by examining the entire seed pool from tree to seed bank. The spatio-temporal dynamics of total seed predation was examined by sampling across its Australian distribution and through time. The main predator was a host-specialist multivoltine beetle, Algarobius prosopis L. (Bruchidae), previously introduced as a biocontrol agent. Seed predation exceeded 20% in all seed stages (in pods on and off the tree, and seeds within woody endocarps (capsules) and free seeds on and in the ground) but was consistently highest in capsules on the ground (up to 90%). Pre-dispersal predation contributed little. Total seed predation rates were primarily determined by predation rates on the most persistent seed stage, in this case fallen pods if only pods are considered and seeds in capsules for the total seed pool. This pattern was consistent across the surveyed taxa, regions, years and seasonally. Predation rate was relatively unaffected by seed density, potentially because densities were always low (

This work describes the synthesis and use of the chelator lipid, nitrilotriacetic acid ditetradecylamine (NTA-DTDA). This lipid is readily dispersed in aqueous media, both alone and when mixed with carrier lipids like dimyristoylphosphatidylcholine (DMPC). Fluorescence microscopic examination of membranes deposited from NTA-DTDA-containing liposomes shows that NTA-DTDA mixes uniformly with the carrier lipid, and does not phase separate. NTA-DTDA-membranes deposited onto the sensing surface of IAsys biosensor cuvettes show good stability, permitting use of the biosensor to study protein interactions. Hexahistidine-tagged proteins including recombinant forms of the extracellular regions of murine B7.1 (B7.1-6H) and of the human erythropoietin receptor (EPOR-6H) bind to NTA-DTDA-membranes; the stability of binding is dependent on both protein concentration, and density of NTA-DTDA. Kinetic measurements show that high stability of anchored proteins (t(1/2) approximately 10-20 h, apparent K(d) approximately 1 nM) can be achieved using membranes containing 25 mol% NTA-DTDA, but low levels of bound protein (

Thin films of diamond-like carbon have been deposited using a photon-enhanced CVD method. Initial results have been reported previously. This paper investigates the possible mechanisms involved in film growth by electrical characterization of the plasma in the chamber, and by relating the variation in film growth rate to deposition pressure. The results indicate that the primary deposition mechanism is due to phyotolysis, with CVD due to diffusion of the hydrogen plasma from the lamp playing a lesser role. Material properties of the films have been studied by many methods, including Raman spectroscopy and elastic recoil detection analysis. These results are reported here and, in agreement with previous work, indicate that the films produced are semiconducting hydrogenated amorphous carbon, with hydrogen concentrations of between 35 and 45 at.%.

Thin films of diamond-like carbon (DLC) have been deposited using a novel photon-enhanced chemical vapour deposition (photo-CVD) method. This low energy method may be a way to produce better interfaces in electronic devices by reducing damage due to ion bombardment. Methane requires high energy photons for photolysis to take place and these are not transmitted in most photo-CVD methods owing to the presence of a window between the lamp and the deposition environment. In our photo-CVD system there is no window and all the high energy photons are transmitted into the reaction gas. Initial work has proved promising and this paper presents recent results. Films have been characterized by measuring electron energy loss spectra, by ellipsometry and by fabricating and testing diode structures. Results indicate that the films are of a largely amorphous nature and are semiconducting. Diode structures have on/off current ratios of up to 106.

Extended abstract of a paper presented at Microscopy and Microanalysis 2013 in Indianapolis, Indiana, USA, August 4 – August 8, 2013.

The compound (C 5 H 5 ) 2 Fe 2 (CO) 3 PPh 3 , previously obtained by the photolysis of (C 5 H 5 ) 2 Fe 2 (CO) 4 with PPh 3 , may also be obtained by reflluxing these same reactants in benzene. The compound was isolated in pure form by means of low temperature column chromatography. It is unstable in solution in the absence of added PPh 3 . Solid samples also are unstable over long periods of time. Decomposition in solution is complete within one hour at 80° yielding a mixture of (C 5 H 5 ) 2 Fe 2 (CO) 4 and (C 5 H 5 ) 4 Fe 4 (CO) 4 . This reaction is suppressed by excess PPh 3 . Heating a mixture of (C 5 H 5 ) 2 Fe 2 (CO) 3 PPh 3 and P(OEt) 3 gives a nearly quantitative yield of (C 5 H 5 ) 2 Fe 2 (CO) 3 P(OEt) 3 . Refluxing a xylene solution of (C 5 H 5 ) 2 Fe 2 (CO) 4 containing a slight molarr excess of PPh 3 for 7 h results in the isolation of (C 5 H 5 ) 4 Fe 4 (CO) 4 in 56% yield, making this reaction by far the most convenient method for the preparation, in gram quantities, of this transition metal cluster.

Infrared (IR)-spectroscopy can analyse a range of molecules in diverse biological systems and has already found use in forensic biology, clinical diagnosis, and environmental monitoring. Using IR-spectroscopy to analyse gastropod mucus represents an original application of this technique. This study describes the differences in mucus composition that appear to be species specific, as well as identifying many of the molecular components of the mucus itself. All species studied showed IR absorbance bands indicating the presence of amide bonds as well as profiles associated with the sugar side chains, indicating a commonality associated with the gel properties of pedal mucus which may have a role in locomotion. The species-specific band profiles may provide an indication of the differing roles required of the mucus by the specific gastropod tested.