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A series of apatites with varying carbonate levels was prepared in order to assign the carbonate bands and calibrate for Raman analysis of natural materials. Overlap of carbonate bands with phosphate peaks was resolved by curve fitting. A peak at 1,071 cm(-1) was assigned to a combination of the carbonate nu(1) mode at 1,070 cm(-1) with a phosphate nu(3) mode at 1,076 cm(-1). In addition, the carbonate nu(4) mode was identified in apatite samples with >4% carbonate. The carbonate nu(4) bands at 715 and 689 cm(-1) identify the samples as B-type carbonated apatite. The carbonate content of apatite was calibrated to a carbonate Raman band, and the method was used to determine the carbonate content of a sample of bovine cortical bone, 7.7 +/- 0.4%.

This study aims to compare impacts of climate change on streamflow in four large representative African river basins: the Niger, the Upper Blue Nile, the Oubangui and the Limpopo. We set up the eco-hydrological model SWIM (Soil and Water Integrated Model) for all four basins individually. The validation of the models for four basins shows results from adequate to very good, depending on the quality and availability of input and calibration data. For the climate impact assessment, we drive the model with outputs of five bias corrected Earth system models of Coupled Model Intercomparison Project Phase 5 (CMIP5) for the representative concentration pathways (RCPs) 2.6 and 8.5. This climate input is put into the context of climate trends of the whole African continent and compared to a CMIP5 ensemble of 19 models in order to test their representativeness. Subsequently, we compare the trends in mean discharges, seasonality and hydrological extremes in the 21st century. The uncertainty of results for all basins is high. Still, climate change impact is clearly visible for mean discharges but also for extremes in high and low flows. The uncertainty of the projections is the lowest in the Upper Blue Nile, where an increase in streamflow is most likely. In the Niger and the Limpopo basins, the magnitude of trends in both directions is high and has a wide range of uncertainty. In the Oubangui, impacts are the least significant. Our results confirm partly the findings of previous continental impact analyses for Africa. However, contradictory to these studies we find a tendency for increased streamflows in three of the four basins (not for the Oubangui). Guided by these results, we argue for attention to the possible risks of increasing high flows in the face of the dominant water scarcity in Africa. In conclusion, the study shows that impact intercomparisons have added value to the adaptation discussion and may be used for setting up adaptation plans in the context of a holistic approach.

The aim of this study was to investigate the impacts of future climate change on discharge and evapotranspiration of the Upper Blue Nile (UBN) basin using multiple global circulation models (GCMs) projections and multiple hydrological models (HMs). The uncertainties of projections originating from HMs, GCMs, and representative concentration pathways (RCPs) were also analyzed. This study is part of the Inter-Sectoral Impact Model Intercomparison Project (ISI-MIP) initiative (phase 2), which is a community driven modeling effort to assess global socio-economic impacts of climate change. The baseline period of 1981–2010 was used to identify climate change signals in two future periods: mid future (2036–2065) and far future (2070–2099). Our analyses showed that two out of four GCMs indicated a statistically significant increase in projected precipitation in the far future period. The projected change in mean annual precipitation varied between 4 and 10% relative to the baseline period. The HMs did not agree on the direction of climate change impacts on mean annual discharge. Furthermore, simulated changes in mean annual discharge by all HMs, except SWIM which simulated up to 6.6% increase for the far future period, were not statistically significant. All the HMs generally simulated a statistically significant increase in annual mean actual evapotranspiration (AET) in both periods. The HMs simulated changes in AET ranging from 1.9 to 4.4% for the far future period. In the UBN basin GCM structure was the main contributor of uncertainty in mean annual discharge projection followed by HM structure and RCPs, respectively. The results from this research suggest to use multiple impact models as well as multiple GCMs to provide a more robust assessment of climate change impacts in the UBN basin.

Hydrogen-bearing species in the bone mineral environment were investigated using solid-state NMR spectroscopy of powdered bone, deproteinated bone, and B-type carbonated apatite. Using magic-angle spinning and cross-polarization techniques three types of structurally-bound water were observed in these materials. Two of these water types occupy vacancies within the apatitic mineral crystal in synthetic carbonated apatite and deproteinated bone and serve to stabilize these defect-containing crystals. The third water was observed at the mineral surface in unmodified bone but not in deproteinated bone, suggesting a role for this water in mediating mineral-organic matrix interactions. Direct evidence of monohydrogen phosphate in a 1H NMR spectrum of unmodified bone is presented for the first time. We obtained clear evidence for the presence of hydroxide ion in deproteinated bone by 1H MAS NMR. A 1H-31P heteronuclear correlation experiment provided unambiguous evidence for hydroxide ion in unmodified bone as well. Hydroxide ion in both unmodified and deproteinated bone mineral was found to participate in hydrogen bonding with neighboring water molecules and ions. In unmodified bone mineral hydroxide ion was found, through a 1H-31P heteronuclear correlation experiment, to be confined to a small portion of the mineral crystal, probably the internal portion.

Two single-well injection–extraction (“push–pull”) tracer tests were performed in a groundwater monitoring well located in the Horonobe coastal sedimentary basin, Japan. The aim of the experiment was to investigate the in situ behavior of groundwater constituents when different mineralized fluids intrude into the aquifer (e.g., through a dynamic saltwater–freshwater interface). Artificially produced brackish water was used as the test fluid in the first experiment and deionized water in the second. Results from mixing models strongly suggest rapid mobilization and demobilization of ions within the aquifer as a reaction to the intruding fluids. Hydraulic modeling of the conservative chloride ions yielded effective porosities of about 1 %. These results show that the transport of ions is dependent on the composition and mineralization of the fluid. The refreshening of an aquifer leads to increased mobilization of ions and, in addition, to an increase of dispersivity due to clay swelling. This has consequences not only for dynamic saltwater–freshwater systems (aquifers in coastal areas and aquifer storage and recovery systems), but also for all systems in which chemically altered fluids come into contact within an aquifer (as, for example, can occur during geothermal heat/energy generation, or during CO 2 storage).

Climate simulations are the fuel to drive hydrological models that are used to assess the impacts of climate change and variability on hydrological parameters, such as river discharges, soil moisture, and evapotranspiration. Unlike with cars, where we know which fuel the engine requires, we never know in advance what unexpected side effects might be caused by the fuel we feed our models with. Sometimes we increase the fuel's octane number (bias correction) to achieve better performance and find out that the model behaves differently but not always as was expected or desired. This study investigates the impacts of projected climate change on the hydrology of the Upper Blue Nile catchment using two model ensembles consisting of five global CMIP5 Earth system models and 10 regional climate models (CORDEX Africa). WATCH forcing data were used to calibrate an eco-hydrological model and to bias-correct both model ensembles using slightly differing approaches. On the one hand it was found that the bias correction methods considerably improved the performance of average rainfall characteristics in the reference period (1970–1999) in most of the cases. This also holds true for non-extreme discharge conditions between Q20 and Q80. On the other hand, bias-corrected simulations tend to overemphasize magnitudes of projected change signals and extremes. A general weakness of both uncorrected and bias-corrected simulations is the rather poor representation of high and low flows and their extremes, which were often deteriorated by bias correction. This inaccuracy is a crucial deficiency for regional impact studies dealing with water management issues and it is therefore important to analyse model performance and characteristics and the effect of bias correction, and eventually to exclude some climate models from the ensemble. However, the multi-model means of all ensembles project increasing average annual discharges in the Upper Blue Nile catchment and a shift in seasonal patterns, with decreasing discharges in June and July and increasing discharges from August to November.

NMR is the technique of election to probe the local properties of materials. Herein we present the results of density functional theory (DFT) \\textit{ab initio} calculations of the NMR parameters for fluorapatite (FAp), a calcium orthophosphate mineral belonging to the apatite family, by using the GIPAW method [Pickard and Mauri, 2001]. Understanding the local effects of pressure on apatites is particularly relevant because of their important role in many solid state and biomedical applications. Apatites are open structures, which can undergo complex anisotropic deformations, and the response of NMR can elucidate the microscopic changes induced by an applied pressure. The computed NMR parameters proved to be in good agreement with the available experimental data. The structural evaluation of the material behavior under hydrostatic pressure (from --5 to +100 kbar) indicated a shrinkage of the diameter of the apatitic channel, and a strong correlation between NMR shielding and pressure, proving the sensitivity of this technique to even small changes in the chemical environment around the nuclei. This theoretical approach allows the exploration of all the different nuclei composing the material, thus providing a very useful guidance in the interpretation of experimental results, particularly valuable for the more challenging nuclei such as \\(^{43}\\)Ca and \\(^{17}\\)O.

The three-subunit aa3-type cytochrome c oxidase (EC 1.9.3.1) of Rhodobacter sphaeroides is structurally and functionally homologous to the more complex mitochondrial oxidase. The largest subunit, subunit I, is highly conserved and predicted to contain 12 transmembrane segments that provide all the ligands for three of the four metal centers: heme a, heme a3, and CuB. A variety of spectroscopic techniques identify these ligands as histidines. We have used site-directed mutagenesis to change all the conserved histidines within subunit I of cytochrome c oxidase from Rb. sphaeroides. Analysis of the membrane-bound and purified mutant proteins by optical absorption and resonance Raman spectroscopy indicates that His-102 and His-421 are the ligands of heme a, while His-284, His-333, His-334, and His-419 ligate the heme a3-CuBcenter. To satisfy this ligation assignment, helices II, VI, VII, and X, which contain these histidine residues, must be in close proximity. These data provide empirical evidence regarding the three-dimensional protein structure at the catalytic core of cytochrome c oxidase.

To determine impact of risk-reducing hysterectomy and bilateral salpingo-oophorectomy (BSO) on gynecological cancer incidence and death in heterozygotes of pathogenic MMR (path_MMR) variants. The Prospective Lynch Syndrome Database was used to investigate the effects of gynecological risk-reducing surgery (RRS) at different ages. Risk-reducing hysterectomy at 25 years of age prevents endometrial cancer before 50 years in 15%, 18%, 13%, and 0% of path_MLH1, path_MSH2, path_MSH6, and path_PMS2 heterozygotes and death in 2%, 2%, 1%, and 0%, respectively. Risk-reducing BSO at 25 years of age prevents ovarian cancer before 50 years in 6%, 11%, 2%, and 0% and death in 1%, 2%, 0%, and 0%, respectively. Risk-reducing hysterectomy at 40 years prevents endometrial cancer by 50 years in 13%, 16%, 11%, and 0% and death in 1%, 2%, 1%, and 0%, respectively. BSO at 40 years prevents ovarian cancer before 50 years in 4%, 8%, 0%, and 0%, and death in 1%, 1%, 0%, and 0%, respectively. Little benefit is gained by performing RRS before 40 years of age and premenopausal BSO in path_MSH6 and path_PMS2 heterozygotes has no measurable benefit for mortality. These findings may aid decision making for women with LS who are considering RRS.