Effects of asymmetric contacts on single molecule conductances of HS(CH2)nCOOH in nano-electrical junctions

A scanning tunnelling microscope has been used to determine the conductance of single molecular wires with the configuration X-bridge-X, X-bridge-Y and Y-bridge-Y (X = thiol terminus and Y = COOH). We find that for molecular wires with mixed functional groups (X-bridge-Y) the single molecule conductance decreases with respect to the comparable symmetric molecules. These differences are confirmed by theoretical computations based on a combination of density functional theory and the non-equilibrium Green functions formalism. This study demonstrates that the apparent contact resistance, as well as being highly sensitive to the type of the anchoring group is also strongly influenced by contact-asymmetry of the single molecular junction which in this case decreases the transmission. This highlights that contact asymmetry is a significant factor to be considered when evaluating nano-electrical junctions incorporating single molecules

Characterization of pharmacists’ interventions in asthma management: A systematic review

© 2018 American Pharmacists Association® Objective: Pharmacists have adopted an active role in asthma management. This review aimed to analyze the intervention dose, understood as the “amount of program delivered,” and core components of the intervention provided by pharmacists in asthma management. Data sources: A literature search was conducted in December 2016 using PubMed. Study selection: A 2-stage approach was used. At the first stage, systematic reviews of pharmacists’ interventions in asthma management were identified. At the second stage, primary studies included in the systematic reviews were selected. Data extraction: The DEPICT-2 (Descriptive Elements of Pharmacist Intervention Characterization Tool) was used for data extraction. In addition GINA (Global Initiative for Asthma) guidelines were used as a reference to classify the interventions’ core components. Results: Thirty-one studies were included. In most of the studies, the pharmacist–patient intervention occurred at the community pharmacy setting (n = 22). The most common core components used in pharmacists’ interventions were the provision of drug information and patient counseling (n = 27). Pharmacists’ interventions frequently were targeted at assessing and improving the use of patient's inhaler technique (n = 27). Educational materials and written action plans were the materials most commonly used in the interventions (n = 20). The duration (n = 13) and the frequency (n = 16) of the intervention were the most frequent information about the intervention dose measure reported. Conclusion: Pharmacists’ interventions in asthma management are complex. Structured educational programs and patient counseling appear to be the most frequent core components of pharmacists’ interventions. Interventions were focused on providing information about the condition and on inhaler technique assessment and training. However, most studies failed to report the intervention dose sufficiently to be reproduced. The reporting of this indicator is crucial to ensure the reproducibility of the interventions assessed and their implementation in practice. (Registration number CRD42016029181.

Vibrationally induced inversion of photoelectron forward-backward asymmetry in chiral molecule photoionization by circularly polarized light

Electron–nuclei coupling accompanying excitation and relaxation processes is a fascinating phenomenon in molecular dynamics. A striking and unexpected example of such coupling is presented here in the context of photoelectron circular dichroism measurements on randomly oriented, chiral methyloxirane molecules, unaffected by any continuum resonance. Here, we report that the forward-backward asymmetry in the electron angular distribution, with respect to the photon axis, which is associated with photoelectron circular dichroism can surprisingly reverse direction according to the ion vibrational mode excited. This vibrational dependence represents a clear breakdown of the usual Franck–Condon assumption, ascribed to the enhanced sensitivity of photoelectron circular dichroism (compared with other observables like cross-sections or the conventional anisotropy parameter-β) to the scattering phase off the chiral molecular potential, inducing a dependence on the nuclear geometry sampled in the photoionization process. Important consequences for the interpretation of such dichroism measurements within analytical contexts are discussed

Climatic Changes, Water Systems, and Adaptation Challenges in Shawi Communities in the Peruvian Amazon

Climate change impacts on water systems have consequences for Indigenous communities. We documented climatic changes on water systems observed by Indigenous Shawi and resultant impacts on health and livelihoods, and explored adaptation options and challenges in partnership with two Indigenous Shawi communities in the Peruvian Amazon. Qualitative data were collected via PhotoVoice, interviews, focus group discussions, and transect walks, and analyzed using a constant comparative method and thematic analysis. Quantitative data were collected via a household survey and analyzed descriptively. Households observed seasonal weather changes over time (n = 50; 78%), which had already impacted their family and community (n = 43; 86%), such as more intense rainfall resulting in flooding (n = 29; 58%). Interviewees also described deforestation impacts on the nearby river, which were exacerbated by climate-related changes, including increased water temperatures (warmer weather, exacerbated by fewer trees for shading) and increased erosion and turbidity (increased rainfall, exacerbated by riverbank instability due to deforestation). No households reported community-level response plans for extreme weather events, and most did not expect government assistance when such events occurred. This study documents how Indigenous peoples are experiencing climatic impacts on water systems, and highlights how non-climatic drivers, such as deforestation, exacerbate climate change impacts on water systems and community livelihoods in the Peruvian Amazon

Cytochrome P450 from Plants: Platforms for Valuable Phytopharmaceuticals

Cytochrome P450 enzymes are important for biotechnology due to their capacity to modify diverse secondary metabolites that may produce chemicals with pharmacological properties. Most terpenes, flavonoids and alkaloids require P450 catalytic functions to reach their biological activity. In the last ten years, several efforts have focused on the expression and production of these three main types of secondary metabolites in engineered microorganisms and plants using P450 of ethnobotanical origin. Despite this, several P450 coding sequences from plant sources are discovered yearly but only a few have been screened by functional genomics. Amongst them, only a few have shown potentials for use in sustainable production of novel drugs and highly valuable products. Cytochrome P450 involvement in the biosynthesis of these products is discussed in this work.Keywords: Biotechnological platforms, Cytochrome P450, Phytopharmaceuticals, Yield improvement, Terpenes, Flavonoids, Alkaloids, Microbial expressio

Tuning of Human Modulation Filters Is Carrier-Frequency Dependent

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