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Collaborations between archeologists and aquatic scientists are driving forward a whole new subdiscipline of methods to document and understand environmental change. Climate change, food webs, El Niño La Niña oscillations, and alterations to biotic factors such as salinity and stream flow have all been studied via aquatic archeological material. Much of this research is conducted on shell middens, the archeological materials they contain, and substrates they are deposited in. This article provides a primer on the formation of shell middens, procedures of midden archeological excavation, and the recent advances in aquatic environmental change research from analyzing archeological material collected from middens.

ABSTRACTRising sea and groundwater levels in coastal Florida have infringed on and wetted archaeological sites with some sites already submerged by rising sea levels. While studies of moisture-induced artifact diagenesis and destruction have been documented elsewhere, very little documentation exists for Florida and the faunal artifacts typical of Florida. This study sought to fill that gap by documenting the effects of wetting experiments on Floridian bone faunal artifacts. Our findings show that moisture-induced diagenesis and destruction is occurring at Florida sites and is more severe in older artifacts. Also, bone artifacts can retain moisture after the surrounding sediment matrix has dried. Furthermore, vertebrae across taxa are especially vulnerable to moisture-induced diagenesis while fish spines and scales are especially resistant. Although our data are limited, mammal bone seems especially vulnerable to diagenetic destruction, mammal bone being completely absent in the older assemblage, which is consistent with other artifact diagenesis studies. The implications of this study are that artifact assemblages excavated in Florida are biased by the postdeposition and pre-excavation loss of artifacts, specifically biased against diagenetic-prone bone (e.g., mammal and vertebrae) and toward diagenetic resilient bone (e.g., boney fish). This has implications both in terms of site interpretation and preservation priorities.

ABSTRACTCoastal low-lying archaeological sites are known to be at risk due to sea-level rise associated with climate change. However, not all of the potential impacts of sea-level rise on these sites have been documented. In this interdisciplinary study we set out to document the effects of rising groundwater tables induced by rising sea level on middens located on barrier islands in southeastern Florida. After excavating two sites, we collected sediment samples that were analyzed for grain size and moisture content. We found that even though these sites are not yet submerged below the groundwater table significant increases in moisture content indicate a subterranean source of the moisture, most likely the capillary fringe above the water table. Increased moisture content of the sediment in which the artifacts are entrained can increase artifact deterioration. Therefore, current and future groundwater water table elevations should be considered when prioritizing sites for excavation and preservation.

Grasslands throughout the world are responding in diverse ways to changing climate and environmental conditions. In this study we analyze indicators of phosphorus limitation including phosphorus concentrations, phosphorus to nitrogen, and carbon ratios, oxygen isotope ratios of phosphate in vegetation, and phosphatase enzyme activity in soil to shed light on potential effects of climate change on phosphorus availability to grassland vegetation. The study was conducted at the Jasper Ridge Global Change Experiment (JRGCE), California where manipulations mimicking increases in temperature, water, nitrogen and carbon-dioxide have been maintained for over 15 years. We compare our results to an earlier study conducted 3 years after the start of the experiment, in order to assess any change in the response of phosphorus over time. Our results suggest that a decade later the measured indicators show similar or only slightly stronger responses. Specifically, addition of nitrogen, the principle parameter controlling biomass growth, increased phosphorus demand but thresholds that suggest P limitation were not reached. A study documenting changes in net primary productivity (NPP) over time at the JRGCE also could not identify a progressive effect of the manipulations on NPP. Combined these results indicate that the vegetation in these grassland systems is not very sensitive to the range of climate parameters tested.

Pyroglutamate-modified amyloid-β(pEAβ) has been described as a relevant Aβspecies in Alzheimer’s-disease-affected brains, with pEAβ(3–42) as a dominant isoform. Aβ(1–40) and Aβ(1–42) have been well characterized under various solution conditions, including aqueous solutions containing trifluoroethanol (TFE). To characterize structural properties of pEAβ(3–42) possibly underlying its drastically increased aggregation propensity compared to Aβ(1–42), we started our studies in various TFE-water mixtures and found striking differences between the two Aβspecies. Soluble pEAβ(3–42) has an increased tendency to form β-sheet-rich structures compared to Aβ(1–42), as indicated by circular dichroism spectroscopy data. Kinetic assays monitored by thioflavin-T show drastically accelerated aggregation leading to large fibrils visualized by electron microscopy of pEAβ(3–42) in contrast to Aβ(1–42). NMR spectroscopy was performed for backbone and side-chain chemical-shift assignments of monomeric pEAβ(3–42) in 40% TFE solution. Although the difference between pEAβ(3–42) and Aβ(1–42) is purely N-terminal, it has a significant impact on the chemical environment of >20% of the total amino acid residues, as revealed by their NMR chemical-shift differences. Freshly dissolved pEAβ(3–42) contains two α-helical regions connected by a flexible linker, whereas the N-terminus remains unstructured. We found that these α-helices act as a transient intermediate to β-sheet and fibril formation of pEAβ(3–42).

Sources of dissolved methane (CH4) at Toolik Lake, Alaska, include both diffusion from lake sediments and groundwater entering the lake from its perimeter. Here we use hydrogen and oxygen isotopes in water (H2O), carbon and hydrogen isotopes in CH4, and carbon isotopes in dissolved inorganic carbon (DIC) to calculate the relative importance of lake sediment and groundwater discharge as sources of dissolved CH4to Toolik Lake. We also resolve the relative importance of the source contribution spatially within the lake and determine the processes controlling CH4concentrations in groundwater surrounding the lake. Our findings, from a mixing model based on isotopes in CH4, suggest that groundwater is a more important source of CH4at the perimeter of the lake where the water-to-air flux is high. Additionally, we find on the local scale that high groundwater methane concentrations may be better linked to areas around the lake where rain is the dominant source of water to the active layer, indicating that changes in precipitation and active layer thaw depth will impact methane concentrations in the active layer and, ultimately, the groundwater associated flux to Toolik Lake. Tundra groundwater is an important source of methane to areas of the lake where the water to air dissolved methane flux is also higherIsotope analyses suggest that bacteria methyl-type fermentation is the major pathway of methane production in the active layerChanges in precipitation in the Arctic could induce changes in methane production in groundwater due to changes in saturated zone thickness This project investigates the cycling of methane, a green house gas, at an Arctic Lake in Alaska. The study shows that increases in rain could cause an increase in the amount of methane transported to Arctic lakes.

The objective of this study was to evaluate the piglet and the mouse as model systems for preterm cortical development. According to the clinical context, we used non invasive EEG recordings. As a prerequisite, we developed miniaturized Ag/AgCl electrodes for full band EEG recordings in mice and verified that Urethane had no effect on EEG band power. Since mice are born with a “preterm” brain, we evaluated three age groups: P0/P1, P3/P4 and P13/P14. Our aim was to identify EEG patterns in the somatosensory cortex which are distinguishable between developmental stages and represent a physiologic brain development. In mice, we were able to find clear differences between age groups with a simple power analysis of EEG bands and also for phase locking and power spectral density. Interhemispheric coherence between corresponding regions can only be seen in two week old mice. The canolty maps for piglets as well as for mice show a clear PAC (phase amplitude coupling) pattern during development. From our data it can be concluded that analytic tools relying on network activity, as for example PAC (phase amplitude coupling) are best suited to extract basic EEG patterns of cortical development across species.

Here, we quantify the flux of methane to the coastal Arctic and North Pacific Oceans via submarine groundwater discharge (SGD), by use of naturally occurring radium isotopes as groundwater tracers, combined with methane concentration measurements of coastal groundwater. Our findings indicate the flux of methane through this process is much greater in the coastal North Pacific (35 ± 27 mg m−1d−1) than the Arctic Ocean (4.1 ± 0.6 to 11.8 ± 3.9 mg m−1d−1). The dominant controls on methane flux through SGD were not methane concentrations in the aquifer but rather the hydrologic characteristics of each site that mitigated or intensified the SGD water volume flux (120 ± 50 m3m−1d−1in the North Pacific compared to 12 ± 4 m3m−1d−1in the Arctic). Tidal pumping was observed to be an especially important control on SGD flux at the North Pacific site.

Within the scope of this paper, the formability of the press hardenable steel 22MnB5 will be investigated with regard to its anisotropic properties at elevated temperatures under the processing conditions of hot stamping. Two different experimental setups have been realized, one at the University of Erlangen-Nuremberg using conductive heating, and the other one at the University of Padova using inductive heating. Both of these equipments enable the characterization of the material anisotropy behavior by performing uniaxial, hot tensile tests in the range of hot stamping temperatures.

In 2000, the authors found endemic infections of mouse hepatitis virus, minute virus of mice, Syphacia obvelata, and Myobia musculi among mice in a large barrier facility at the University of Mainz. To eliminate the infections, they subdivided the facility into two distinct hygiene units. However, architectural constraints made it impossible to completely separate the HVAC systems of both hygiene units and to establish adequate personnel locks. To compensate for these suboptimal barrier conditions of the two newly established units, the authors replaced the open-top caging and open-servicing system with filter-top cages that were manipulated in cage-changing stations. The authors then depopulated the two units in series, independently eliminating the contaminated mice and restocking the units with SPF animals. In spite of the high infection pressure and the suboptimal barrier conditions, the authors had only a single case of recontamination.

O6-Substituted guanine derivatives are powerful agents used for tumor cell sensitization by inhibition of the DNA repair enzyme O6-methylguanine-DNA methyltransferase (MGMT). To provide targeted accumulation of MGMT inhibitors in tumor tissue as well as tools for in vivo imaging, we synthesized iodinated C8-alkyl-linked glucose conjugates of 2-amino-6-(5-iodothenyl)-9H-purine (O6-(5-iodothenyl) guanine, ITG) and 2-amino-6-(3-iodobenzyloxy)-9H-purine (O6-(5-iodobenzyl) guanine, IBG). These compounds have MGMT inhibitor constants (IC50 values) of 0.8 and 0.45 μM for ITGG and IBGG, respectively, as determined in HeLa S3 cells after 2-h incubation with inhibitor. To substantiate that the 131I−(hetero)arylmethylene group at the O6-position of guanine is transferred to MGMT, both the glucose conjugated inhibitors ITGG and IBGG and the corresponding nonglucose conjugated compounds ITG and IBG were labeled with iodine-131. The radioiodinations of all compounds with [131I]I- were performed with radiochemical yields of >70% for the destannylation of the corresponding tri-n-butylstannylated precursors. The binding ability of [131I]ITGG, [131]IBGG, [131I]ITG, and [131I]IBG to purified MGMT was tested. All radioactive compounds were substrates for MGMT, as demonstrated using a competitive repair assay. The newly synthesized radioactive inhibitors were utilized to study ex vivo biodistribution in mice, and the tumor-to-blood ratio of tissue uptake of [131I]IBG and [131I]IBGG was determined to be 0.24 and 0.76 after 0.5 h, respectively.

Zusammenfassung.Innerhalb von Organisationen und Betrieben wird durch den Einsatz von Arbeits- und Projektgruppen ein “Gruppenvorteil“ in Form besserer Ergebnisse, schnellerer Entscheidungsfindung und breiterer Zustimmung erwartet. Häufig bedarf es jedoch eines derart hohen Aufwandes an Koordinations- und Integrationsleistungen, um den vielfältigen Argumenten, Einstellungen und Informationen gerecht zu werden, dass diese Erwartungen sich nicht erfüllen. Der Einsatz von Moderationstechniken soll diese Koordinations- und Integrationsleistungen erleichtern und gleichzeitig sozio-emotionale Prozesse steuern. Moderationstechniken, die theoriegeleitet die wesentlichen kognitions- und sozialpsychologischen Leistungskriterien berücksichtigen, liegen in Form der am Arbeitsbereich Sozialpsychologie der Universität Hamburg entwickelten Formalen Moderation (FORMOD) und Prozeduralen Moderation (PROMOD) vor. Experimentell konnte im Rahmen eines DFG-Projektes gezeigt werden, dass die wissensbasierte Technik PROMOD der ebenfalls untersuchten FORMOD hinsichtlich der Leistung beim komplexen Problemlösen signifikant mit mittlerer Effektstärke überlegen ist und dass sich der Einsatz beider Moderationstechniken als leistungssteigernd im Vergleich zu nicht-moderierten Gruppen erweist. Neben Leistungsparametern wurden die individuellen Problemlösestrategien und die Konformitätsprozesse als abhängige Variablen zur Vergleichsmessung herangezogen. Die experimentell erzielten Ergebnisse bezüglich der Gruppenleistung und die Darstellung der in FORMOD und PROMOD integrierten Leistungsparameter untermauern die Forderung nach einer theoriegeleiteten Entwicklung integrativer und komplexitätsangemessener Methoden zur Leistungsverbesserung in Arbeitsgruppen. Erste Praxistransfers der Methoden in die betriebliche Realität werden dargestellt und diskutiert.

The formate anion, HCO2−, has been used infrequently as a building block in molecular magnetic materials. We have synthesized and structurally and magnetically characterized two new CuHCO22L compounds, where L represents pyrazine pyz and 4,4′-bipyridine bipy. The single crystal structure of CuHCO22pyz, 1, has been established by both X-ray 295 K and neutron diffraction 20 K. The compound consists of tetragonally-elongated CuN2O4octahedra made up of four bridging formate anions and two neutral pyz ligands. The 3D polymeric network is comprised of 2D CuHCO22layers that are fused together by the linear pyz spacers, which form Cu–pyz-Cu chains. CuHCO22bipy, 2, is chiral and has a more complex framework than 1. The CuO4N2octahedra align in two unique orientations relative to one another, owing to the 41and 21screw axes that lie along the aand b-axes. The octahedra are connected viafour bridging HCO2−anions and two bridging bipy ligands, resulting in a unique 3D scaffold structure. The magnetic behavior of 1and 2indicates antiferro- and ferromagnetic interactions, respectively, and the exchange couplings in both 1and 2are well reproduced by a 1D spin Hamiltonian. Spin dimer analysis was carried out to evaluate the relative strengths of the various spin exchange paths. It is found that the interaction through HCO2−is comparatively weak, and the strong Cu2spin exchange interactions are mediated by the pyz and bipy ligands viathe σ-pathway. A possible reason as to why 2displays ferromagnetic coupling is proposed.

The formate anion, HCO₂−, has been used infrequently as a building block in molecular magnetic materials. We have synthesized and structurally and magnetically characterized two new Cu(HCO₂)₂L compounds, where L represents pyrazine (pyz) and 4,4'-bipyridine (bipy). The single crystal structure of Cu(HCO₂)₂(pyz), 1, has been established by both X-ray (295 K) and neutron diffraction (20 K). The compound consists of tetragonally-elongated CuN₂O₄ octahedra made up of four bridging formate anions and two neutral pyz ligands. The 3D polymeric network is comprised of 2D Cu(HCO₂)₂ layers that are fused together by the linear pyz spacers, which form Cu–pyz-Cu chains. Cu(HCO₂)₂(bipy), 2, is chiral and has a more complex framework than 1. The CuO₄N₂ octahedra align in two unique orientations relative to one another, owing to the 4₁ and 2₁ screw axes that lie along the a and b-axes. The octahedra are connected via four bridging HCO₂− anions and two bridging bipy ligands, resulting in a unique 3D scaffold structure. The magnetic behavior of 1 and 2 indicates antiferro- and ferromagnetic interactions, respectively, and the exchange couplings in both 1 and 2 are well reproduced by a 1D spin Hamiltonian. Spin dimer analysis was carried out to evaluate the relative strengths of the various spin exchange paths. It is found that the interaction through HCO₂− is comparatively weak, and the strong Cu2+ spin exchange interactions are mediated by the pyz and bipy ligands via the σ-pathway. A possible reason as to why 2 displays ferromagnetic coupling is proposed.