DNA origami-assembled metal–semiconductor junctions have been formed as a step toward application of these nanomaterials in nanoelectronics. Previously, techniques such as electroless plating, ...electrochemical deposition, or photochemical reduction have been used to connect metal and semiconductor nanomaterials into desired patterns on DNA templates. To improve over prior work and provide a more general framework for the creation of electronic nanodevices as an alternative nanofabrication step, we have developed a method to connect gold (Au) and tellurium (Te) nanorods on a single DNA origami template without electroplating by annealing after coating with a heat-resistant polymer. Bar DNA origami templates (17 nm × 410 nm) were seeded site-specifically with Au and Te nanorods in an alternating manner. These templates were then coated with a polymer and annealed at different temperatures. At 170 °C, the Au and Te nanorods were best connected, and we hypothesize that the junctions were established primarily due to the atomic mobility of gold. Electrical characterization of these Au/Te/Au assemblies revealed some nonlinear current–voltage curves, as well as linear plots that are explained. This annealing method and the metal–semiconductor nanomaterials that are formed simply through controlled seeding and annealing on DNA origami templates have potential to yield complex nanoelectronic devices in the future.
Submarine groundwater discharge (SGD) is a ubiquitous source of meteoric fresh groundwater and recirculating seawater to the coastal ocean. Due to the hidden distribution of SGD, as well as the ...hydraulic- and stratigraphy-driven spatial and temporal heterogeneities, one of the biggest challenges to date is the correct assessment of SGD-driven constituent fluxes. Here, we present results from a 3-dimensional seasonal sampling campaign of a shallow subterranean estuary in a high-energy, meso-tidal beach, Spiekeroog Island, Northern Germany. We determined beach topography and analyzed physico-chemical and biogeochemical parameters such as salinity, temperature, dissolved oxygen, Fe(II) and dissolved organic matter fluorescence (FDOM). Overall, the highest gradients in pore water chemistry were found in the cross-shore direction. In particular, a strong physico-chemical differentiation between the tidal high water and low water line was found and reflected relatively stable in- and exfiltrating conditions in these areas. Contrastingly, in between, the pore water compositions in the existing foreshore ridge and runnel system were very heterogeneous on a spatial and temporal scale. The reasons for this observation may be the strong morphological changes that occur throughout the entire year, which affect the exact locations and heights of the ridge and runnel structures and associated flow paths. Further, seasonal changes in temperature and inland hydraulic head, and the associated effect on microbial mediated redox reactions likely overprint these patterns. In the long-shore direction the pore water chemistry varied less than the along the cross-shore direction. Variation in long-shore direction was probably occurring due to topography changes of the ridge-runnel structure and a physical heterogeneity of the sediment, which produced non-uniform groundwater flow conditions. We conclude that on meso-tidal high energy beaches, the rapidly changing beach morphology produces zones with different approximations to steady-state conditions. Therefore, we suggest that zone-specific endmember sampling is the optimal strategy to reduce uncertainties of SGD-driven constituent fluxes.
Accumulation of beta amyloid (Aβ) in the brain is a primary feature of Alzheimer's disease (AD) but the exact molecular mechanisms by which Aβ exerts its toxic actions are not yet entirely clear. We ...documented pathological changes 3 and 6 months after localised injection of recombinant, bi-cistronic adeno-associated viral vectors (rAAV2) expressing human Aβ40-GFP, Aβ42-GFP, C100-GFP or C100(V717F)-GFP into the hippocampus and cerebellum of 8 week old male mice. Injection of all rAAV2 vectors resulted in wide-spread transduction within the hippocampus and cerebellum, as shown by expression of transgene mRNA and GFP protein. Despite the lack of accumulation of Aβ protein after injection with AAV vectors, injection of rAAV2-Aβ42-GFP and rAAV2- C100(V717F)-GFP into the hippocampus resulted in significantly increased microgliosis and altered permeability of the blood brain barrier, the latter revealed by high levels of immunoglobulin G (IgG) around the injection site and the presence of IgG positive cells. In comparison, injection of rAAV2-Aβ40-GFP and rAAV2-C100-GFP into the hippocampus resulted in substantially less neuropathology. Injection of rAAV2 vectors into the cerebellum resulted in similar types of pathological changes, but to a lesser degree. The use of viral vectors to express different types of Aβ and C100 is a powerful technique with which to examine the direct in vivo consequences of Aβ expression in different regions of the mature nervous system and will allow experimentation and analysis of pathological AD-like changes in a broader range of species other than mouse.
Although essential for reconstructing hominin behaviour during the Early Palaeolithic, only a handful of Acheulean sites have been dated in the Eastern Sahara region. This is due to the scarcity of ...sites for this time period and the lack of datable material. However, recent excavations in the Atbara region (Sudan) have provided unique opportunities to analyse and date Acheulean stone tools. We report here on EDAR 7, part of a cluster of Acheulean and Middle Stone Age (MSA) sites that were recently discovered in the Eastern Desert Atbara River (EDAR) region, located in the Eastern Desert (Sudan) far from the Nile valley. At EDAR 7, a 3.5 metre sedimentary sequence was excavated, allowing an Acheulean assemblage to be investigated using a combination of sedimentology, stone tool studies and optically stimulated luminescence dating (OSL). The site has delivered a complete Acheulean knapping chaine opératoire, providing new information about the Saharan Acheulean. The EDAR 7 site is interpreted as a remnant of a campsite based on the co-occurrence of two reduction modes: one geared towards the production of Large Cutting Tools (LCTs), and the other based on the flaking of small debitage and production of flake tools. Particularly notable in the EDAR 7 assemblage is the abundance of cleavers, most of which display evidence of flake production. Implementation of giant Kombewa flakes was also observed. A geometric morphometric analysis of hand-axes was conducted to verify a possible Late Acheulean assemblage standardisation in the Nubian Sahara. In addition, the analysis of micro-traces and wear on the artefacts has provided information on the use history of the Acheulean stone tools. Sediment analyses and OSL dating show that the EDAR 7 sequence contains the oldest Acheulean encampment remains in the Eastern Sahara, dated to the MIS 11 or earlier. This confirms that Homo erectus occupied the EDAR region during Middle Pleistocene humid periods, and demonstrates that habitable corridors existed between the Ethiopian Highlands, the Nile and the Red Sea coast, allowing population dispersals across the continent and out of it.
In this work, different metal oxides containing Ti, Zr and Al were prepared and characterized and their catalytic activities for cracking, transesterification, and hydroesterification reactions of ...soybean oil were evaluated. It is described the synthesis of the solids by co-precipitation, and their characterization by thermogravimetry, X-ray diffraction, Brunauer-Emmet-Teller surface area determination, Fourier-transformed Raman spectroscopy, and the determination of Lewis and Brønsted acid sites by pyridine adsorption and detection through Fourier transform infrared spectroscopy (FTIR). The hydrocarbons obtained by soybean pyrolysis were analyzed by fractional distillation, acid number, FTIR, density (at 20 °C), viscosity (at 40 °C), and calculation of the cetane number. The results suggest that all of the solids exhibit catalytic activity at the second stage of the cracking reaction (deoxygenation), lowering the final acidity of the products. The solids also exhibited catalytic activity for transesterification and hydroesterification of triacylglycerides, leading to good yields in methyl fatty acid esters.
There remains no consensus on indication or technique for repair of pancreaticoduodenal artery aneurysms (PDAA) due to the fact that they are exceedingly rare. We sought to evaluate risk factors for ...rupture, as well as compare the outcomes of open and endovascular surgery.
We performed a retrospective review of all PDAAs over a 15-year period. The primary outcome was technical success, defined as complete cessation of flow within the aneurysm sac on follow-up imaging. Secondary outcomes included complications greater than Clavien-Dindo Grade I.
A total of 21 PDAAs was identified (mean size 20 mm, interquartile range 8-32). Eight patients (38%) were male with an average age at diagnosis of 54.3 ± 2.4 years. Aneurysm etiology included degenerative (90%), pancreatitis (14%), and connective tissue disorder (5%). Seven patients (33%) had additional aneurysms on imaging. Ten patients (48%) were asymptomatic, while 5 patients (24%) presented with rupture. Six patients (29%) had an open repair, including 4 aneurysm ligations and 2 emergent Whipple procedures. Eleven patients underwent an endovascular intervention including 10 (48%) embolizations and 1 stent-assisted coiling (9%). Technical success was 100% for the open group and 91% in the endovascular group. Clavien-Dindo grade >1 complications occurred in 67% of open patients and 0% of endovascular patients (P = 0.01). Death occurred in 2 ruptured patients who underwent open repair. On univariate analysis, male gender was statistically associated with rupture (P = 0.02); however, size of the aneurysm was not (P = 0.77). There was a trend toward an increased rupture rate in those with celiac stenosis (P = 0.10).
In one of the largest series of PDAA to date, only male gender was associated with rupture. Furthermore, size of the aneurysm was not associated with rupture and should not be considered a criterion for repair. While technical success was greater in the open group, it was also associated with an increased incidence of clinically significant complications and death. Endovascular aneurysm embolization should be considered the treatment of choice.
CO oxidation on Ru(0001) is a long-standing example of
a reaction
that, being thermally forbidden in ultrahigh vacuum, can be activated
by femtosecond laser pulses. In spite of its relevance, the ...precise
dynamics of the photoinduced oxidation process as well as the reasons
behind the dominant role of the competing CO photodesorption remain
unclear. Here we use ab initio molecular dynamics with electronic
friction that account for the highly excited and nonequilibrated system
created by the laser to investigate both reactions. Our simulations
successfully reproduce the main experimental findings: the existence
of photoinduced oxidation and desorption, the large desorption to
oxidation branching ratio, and the changes in the O K-edge X-ray absorption
spectra attributed to the initial stage of the oxidation process.
Now, we are able to monitor in detail the ultrafast CO desorption
and CO oxidation occurring in the highly excited system and to disentangle
what causes the unexpected inertness to the otherwise energetically
favored oxidation.
Terrestrial surface waters and submarine ground water discharge (SGD) act as a source of dissolved substances for coastal systems. Solute fluxes of SGD depend on the ground water composition and the ...water-solid-microbe interactions close to the sediment-water interface. Thus, this study aims to characterize and evaluate the hydrogeochemical gradients developing in the fresh-salt water mixing zone of the Wismar Bay (WB), southern Baltic Sea, Germany. Sampling campaigns covering the WB, the fresh-salt water mixing zone at the beach of the WB shoreline, terrestrial surface and ground waters near the WB as well sediments pore water were carried out. In these different waters, the distribution of dissolved inorganic carbon, nutrients, major ions, trace elements, stable isotopes (H, O, C, S), and radium isotopes have been investigated. Enhanced concentrations of radium isotopes together with dissolved manganese, barium in the surface waters of the eastern WB indicated benthic-pelagic coupling via the exchange between pore water and the water column. Salinity, stable isotopes, and major ions in sediment pore water profiles identified the presence of fresh ground water below about 40 cmbsf in the central part of the bay. Geophysical acoustic techniques revealed the local impact of anthropogenic sediment excavation, which reduced the thickness of a sediment layer between the coastal aquifer and the bottom water, causing, therefore, a ground water upward flow close to the top sediments. The fresh impacted pore water stable isotope composition (δ
18
O, δ
2
H) plot close to the regional meteoric water line indicating a relatively modern ground water source. The calculated organic matter mineralization rates and the dissolved inorganic carbon sediment-water fluxes were much higher at the fresh impacted site when compared to other unimpacted sediments. Therefore, this study reveals that different fresh water sources contribute to the water balance of WB including a SGD source.
Robinson, L, Murray, A, Ehlert, A, Wells, J, Jarvis, P, Turner, A, Glover, D, Coughlan, D, Hembrough, R, and Bishop, C. Effects of physical training and associations between physical performance ...characteristics and golf performance in female players: A systematic review with meta-analysis. J Strength Cond Res 37(12): e646-e655, 2023-The aims of this systematic review were to assess the association between physical performance and measures of golf performance, and the effects of physical training on measures of golf performance, in female golfers. A systematic literature search was conducted in PubMed, SPORTDiscus, Medline, and CINAHL. Inclusion criteria required studies to (a) have conducted a physical training intervention of any duration in female players and determine the effects on measures of golf performance, (b) determine the association between physical performance in at least one test and golf performance in female players, and (c) be peer-reviewed and published in English language. Methodological quality was assessed using a modified version of the Downs and Black Quality Index tool, and heterogeneity was examined through the Q statistic and I2 . Pooled effect sizes were calculated using standardized mean differences (SMDs) (with 95% confidence interval CIs) within a random-effects model, with Egger's regression test used to assess small study bias (inclusive of publication bias). Of the 2,378 articles screened, only 9 were included in the final review, with 3 of these being associative by design and 6 being training interventions. From an associative standpoint, clubhead speed (CHS) was reported in all 3 studies and was associated with measures of strength ( r = 0.54), lower-body power ( r = 0.60), upper-body power ( r = 0.56-0.57), and flexibility ( r = 0.52-0.71). When assessing the effects of physical training interventions, CHS was again the most commonly reported golf outcome measure ( n = 5). The random-effect model indicated that CHS significantly improves within each training group following training interventions (SMD = 0.73 95% CIs: 0.32-1.14, Z = 3.50, p < 0.001), with trivial heterogeneity ( I2 = 0.00%, Q = 0.18; p = 0.9963) and no prevalence of small study bias depicted through the Egger's regression test ( z = -0.28, p = 0.78). From the available research, it seems that CHS can be positively affected from strength, power, and flexibility training interventions. From an associative standpoint, only 3 studies have been conducted solely in female players, with one showcasing questionable methodology. Future research should aim to carefully select test measures which better represent the physical capacities needed for the sport when determining the effects of and relationships with golf performance.
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