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Chelation-controlled regioselective endo cleavage and stereoselective C-1 alkylation of pentofuranosides

Combinations of Lewis acids and nucleophilic reagents trigger endo-opening of the furanoside ring of methyl furanosides 1, 10 and 13, resulting in the attachment of the nucleophilic group at C-1 of the carbohydrate. The stereoselectivity in the C-C bond-forming step is low for the 2-deoxyfuranosides but very high (dr 1:99) for the furanosides carrying a methoxy group in the 2-position when a combi

An instrument variable based algorithm for estimating cross-correlated hydrological remote sensing errors

Optimally using multi-source remote-sensing (RS) and/or reanalyzed hydrological products requires knowledge of each product's accuracy and inter-product error cross-correlations. Quadruple collocation (QC) analysis can potentially solve for this error information without the reliance of high-quality ground references. However, QC requires at least three independent products for a variable of inter

Application of SWAT for sediment yield estimation in a mountainous agricultural basin

The advanced SWAT (Soil and Water Assessment Tool) model is based on hydrologic process and needs to be calibrated and validated prior to application. This paper presents a case study conducted in Chaohe river upstream to verify the applicability of SWAT for predicting sediment yields in a semi-arid mountainous basin. Utilizing the gage records, the SWAT was deeply explored in the study area. The

Effects of molar expansion ratio of fuels on engine efficiency

Fuel properties have a strong impact on the efficiency of internal combustion engines. Contrary to other physical and thermochemical fuel properties, the molar expansion ratio is normally ignored. Molar expansion ratio is the ratio of number of moles of the products to the reactants. In this work, the impact of the fuel's molar expansion ratio on engine efficiency is investigated. Findings are bas

Believed effect - A prerequisite but not a guarantee for acceptance of carnivore management interventions

Conflicts over wildlife and their potential impacts on human practices and livelihoods are widespread. Large carnivore predation on livestock often becomes a contested topic which has led to global declines in carnivore numbers over centuries. To minimise impacts of carnivores on human livelihoods and allow conservation, various interventions are used to prevent attacks. However, these interventio

A 5 GHz CT ^Delta;Σ ADC with 250 MHz Signal Bandwidth in 28 nm-FDSOI CMOS

This paper presents a continuous-time ΔΣ ADC in a 28nm-FDSOI CMOS technology. The ADC is clocked at 5GHz with a signal bandwidth of 250 MHz, for an oversampling ratio (OSR) of only 10. The conversion from high-level model to circuit-level implementation requires multiple high-speed design methodologies and a careful layout. A 4th order loop filter is adopted to enhance quantization noise shaping i

Introducing the Endotype Concept to Address the Challenge of Disease Heterogeneity in Type 1 Diabetes

The clinical diagnosis of new-onset type 1 diabetes has, for many years, been considered relatively straightforward. Recently, however, there is increasing awareness that within this single clinical phenotype exists considerable heterogeneity: disease onset spans the complete age range; genetic susceptibility is complex; rates of progression differ markedly, as does insulin secretory capacity; and

3-Substituted 1-Naphthamidomethyl-C-galactosyls Interact with Two Unique Sub-Sites for High-Affinity and High-Selectivity Inhibition of Galectin-3

The galectins are a family of galactose-binding proteins playing key roles in inflammatory processes and cancer. However, they are structurally very closely related, and discovery of highly selective inhibitors is challenging. In this work, we report the design of novel inhibitors binding to a subsite unique to galectin-3, which confers both high selectivity and affinity towards galectin-3. Olefin

A Self-Sustaining Model for Peer-to-Peer Engineering Education Among Children in Low Resource Environments

Engineering education among children has the potential to spark their interest in technical subjects, overcome gender imbalances within the field, and empower young people with the tools to make positive changes in their communities. However, it can be difficult to integrate into existing school curricula, especially when resources are constrained.Here I present a one-year case study conducted in

Återkoppling mellan lärare och studenter ur ett reglertekniskt perspektiv

Återkoppling är centralt för lärandeprocessen. Studenterna behöver få konstruktiv feedback på sina prestationer för att lärandet ska bli effektivt och lyckat. Återkoppling är även ett centralt begrepp inom reglertekniken, där man med hjälp av feedback kan få olika tekniska processer att bete sig på önskat sätt. Vi ställer oss frågan om vilka insikter man kan nå genom att analysera lärandesituation

Workplace Emissions and Exposures During Semiconductor Nanowire Production, Post-production, and Maintenance Work

BackgroundNanowires are a high-aspect-ratio material of increasing interest for a wide range of applications. A new and promising method to produce nanowires is by aerotaxy, where the wires are grown in a continuous stream of gas. The aerotaxy method can grow nanowires much faster than by more conventional methods. Nanowires have important properties in common with asbestos fibers, which indicate

Characterization of histamine receptors mediating contraction and relaxation of the ovarian follicle wall

Histamine is known to be present in ovarian tissue and may play a role in the ovulation process. The effect of histamine on the follicular smooth musculature was investigated using strips from the protruding part of mature bovine follicles, mounted in vitro for registration of isometric motor activity. Histamine contracted the preparation in a concentration-dependent manner. The response was inhib

A global database for metacommunity ecology, integrating species, traits, environment and space

The use of functional information in the form of species traits plays an important role in explaining biodiversity patterns and responses to environmental changes. Although relationships between species composition, their traits, and the environment have been extensively studied on a case-by-case basis, results are variable, and it remains unclear how generalizable these relationships are across e

Acquisitions, entry, and innovation in oligopolistic network industries

In industries with network effects, incumbents' installed bases create barriers to entry that discourage entrepreneurs from developing new innovations. Yet, entry is not the only commercialization route for entrepreneurs. We show that the option of selling to an incumbent increases the innovation incentives for entrepreneurs when the network effects are strong and incumbents compete to preemptivel