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Rapid increase in cosmogenic C-14 in AD 775 measured in New Zealand kauri trees indicates short-lived increase in C-14 production spanning both hemispheres

In 2012, Miyake et al. reported a sudden and strong increase of the atmospheric radiocarbon (C-14) content in Japanese cedar trees of 1.2% between AD 774 and 775. While their findings were quickly confirmed by a German oak chronology for the Northern Hemisphere (NH), the question remained if the effect was seen in both hemispheres. Here we present the first annually resolved Southern Hemisphere (S

Periodically Changing Morphology of the Growth Interface in Si, Ge, and GaP Nanowires

Nanowire growth in the standard < 111 > direction is assumed to occur at a planar catalyst-nanowire interface, but recent reports contradict this picture. Here we show that a nonplanar growth interface is, in fact, a general phenomenon. Both III-V and group IV nanowires show a distinct region at the trijunction with a different orientation whose size oscillates during growth, synchronized with ste

Covalent immobilization of molecularly imprinted polymer nanoparticles using an epoxy silane.

Molecularly imprinted polymers (MIPs) can be used as antibody mimics to develop robust chemical sensors. One challenging problem in using MIPs for sensor development is the lack of reliable conjugation chemistry that allows MIPs to be fixed on transducer surface. In this work, we study the use of epoxy silane to immobilize MIP nanoparticles on model transducer surfaces without impairing the functi

Heterogeneity in Self-Assessed Health Status Among the Elderly in India

The authors examine the observed heterogeneity in self-assessed health (SAH) among the aged in India using data on health and living conditions of the elderly in India from the 60th Round of National Sample Survey (2004-2005). Results indicate that almost one fourth of the old in India rate their health as poor, and there exists considerable interstate variations in SAH ratings. Based on hypothese

Phase-scanning approach to correct time-shift inaccuracies in the surface-wave walk-away method

In order to maintain lateral resolution while maximizing investigation depth in a multichannel surface wave method, it is beneficial to implement the walk-away approach by using a relatively short receiver spread. Combined walk-away records, however, normally suffer from time-shift inaccuracies that adversely influence the subsequent dispersion imaging process. Time-shift inaccuracies produce phas

Effects of prescribed antihypertensives and other cardiovascular drugs on mortality in patients with atrial fibrillation and hypertension: a cohort study from Sweden.

Although antihypertensive drugs are known to reduce mortality in individuals with hypertension, the effects of different cardiovascular pharmacotherapies on mortality among patients with hypertension and atrial fibrillation (AF) have been less thoroughly explored. To study mortality rates in men and women separately with hypertension and AF prescribed different cardiovascular pharmacotherapies. A

Organizational Adaptation in Multi-Stakeholder Crisis Response: An Experimental Study

Modern day crises demand organizations to collaborate and adapt to new roles, functions and structures. In such situations, lack of collaborative behaviour and openness between organizations can result in reduced adaptive ability. Therefore, it is important to facilitate collaboration between organizations.We have studied the extent to which crisis managers are prepared to work with personnel and

g-factor Measurements at RISING: The Cases of 127Sn and 128Sn

We report on g-factor measurements of the 19/2(+) T-1/2 = 4.5(3) mu s isomer in Sn-127 and the 10(+) T-1/2 = 2.69(23) mu s isomer in Sn-128. These isomers were produced and spin-aligned in relativistic heavy-ion fragmentation at GSI and were selected and separated by the GSI fragment separator ( FRS). The gamma-rays of the isomeric decay were detected by the RISING gamma-ray spectrometer. The meth

Climate forcing reconstructions for use in PMIP simulations of the last millennium (v1.0)

Simulations of climate over the Last Millennium (850-1850 CE) have been incorporated into the third phase of the Paleoclimate Modelling Intercomparison Project (PMIP3). The drivers of climate over this period are chiefly orbital, solar, volcanic, changes in land use/land cover and some variation in greenhouse gas levels. While some of these effects can be easily defined, the reconstructions of sol

When Do Water-Insoluble Polyion-Surfactant Ion Complex Salts "Redissolve" by Added Excess Surfactant?

The redissolution of water-insoluble polyion-surfactant ion complexes by added excess of surfactant has systematically been investigated in experimental and theoretical phase equilibrium studies. A number of stoichiometric polyion-surfactant ion "complex salts" were synthesized and they consisted of akyltrimethylammonium surfactant ions of two different alkyl chain lengths (C(12)TA(+) and C(16)TA(

Study of the Polymorphism in Copper(II) Decanoate through Its Phase Diagram with Decanoic Acid, and Texture of the Columnar Thermotropic Liquid Crystal Developable Domains in This and Similar Systems

A new third polymorph of copper(II) decanoate has been found by two methods: from the crystallization of the saltacid solution and from a specific thermal treatment of the polymorph obtained in n-heptane. The new polymorph, whose crystal structure has been solved for the first time, is the most stable from the thermodynamic point of view. It presents a bilayer structure, but with two different typ

Hot spots of vegetation-climate feedbacks under future greenhouse forcing in Europe

We performed simulations of future biophysical vegetation-climate feedbacks with a regional Earth System Model, RCA-GUESS, interactively coupling a regional climate model and a process-based model of vegetation dynamics and biogeochemistry. Simulated variations in leaf area index and in the relative coverage of evergreen forest, deciduous forest, and open land vegetation in response to simulated c

Feed rate control in fed-batch fermentations based on frequency content analysis.

A new strategy for controlling substrate feed in the exponential growth phase of aerated fed-batch fermentations is presented. The challenge in this phase is typically to maximize specific growth rate while avoiding the accumulation of overflow metabolites which can occur at high substrate feed rates. In the new strategy, regular perturbations to the feed rate are applied and the proximity to over

Kinetics of cisplatin binding to short r(GG) containing miRNA mimics - influence of Na(+)versus K(+), temperature and hydrophobicity on reactivity.

Nucleic acids are well recognized targets for platinum-based anticancer drugs, with RNA and DNA being kinetically comparable. In the case of RNA, previous studies have shown that the reaction between small duplex RNAs (dsRNAs) and monoaquated cisplatin (cis-Pt(NH3)2Cl(OH2)(+), ) can be followed by the metal induced hyperchromicity occurring directly after addition of to e.g. microRNA mimics. In th

Automating efficiency-targeted approximations in modelling and simulation tools: dynamic decoupling and mixed-mode integration

Modelling and simulation nowadays permeate virtually any engineering activity, requiring tools capable of managing complex models efficiently. Nonetheless, whereas modern modelling languages and tools allow to construct such models even on lightweight platforms (e.g., a laptop), the same is not true when it comes to numerically integrate those models. For the latter purpose, modellers usually purs

Wideband and Non-Dispersive Wavelet Transmission using Leaky Lens Antenna

An ultra-wideband, non-dispersive leaky lens antenna system for impulse applications has been designed, fabricated and characterized. An in-house wavelet generator is connected to the antenna to transmit 100 ps-long square pulses with center frequencies at 45, 60 and 75 GHz. It is shown that the leaky lens antenna has negligible distortion and preserves the pulse shape generated by the millimeter-

The global relationship between climate, net primary production and the diet of spiders

Aim We compiled data on prey utilization of spiders at a global scale to better understand the relationship between current climate or net primary production (NPP) and diet breadth, evenness and composition in spiders. We test whether the productivity and the diversity–climatic-stability (DCS) hypotheses focusing on diversity patterns may also explain global patterns in prey utilization by web-bui

Competitive capacitive biosensing technique (CCBT): A novel technique for monitoring low molecular mass analytes using glucose assay as a model study.

A novel technique for monitoring of low molecular mass analytes using a flow-injection capacitive biosensor is presented. The method is based on the ability of a small molecular mass analyte to displace a large analyte-carrier conjugate from the binding sites of an immobilized biorecognition element with weak affinity to both compounds. A model study was performed on glucose as the small molecular

Iridium Catalyzed Carbocyclizations: Efficient (5+2) Cycloadditions of Vinylcyclopropanes and Alkynes.

Third-row transition metal catalysts remain a largely untapped resource in cycloaddition reactions for the formation of medium-sized rings. Herein, we report the first examples of iridium-catalyzed inter- and intramolecular vinylcyclopropane (VCP)-alkyne (5+2) cycloadditions. DFT modeling suggests that catalysis by iridium(I) proceeds through a mechanism similar to that previously reported for rho