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We investigate electron transport through a mono-atomic wire which is tunnel coupled to two electrodes and also to the underlying substrate. The setup is modeled by a tight-binding Hamiltonian and can be realized with a scanning tunnel microscope (STM). The transmission of the wire is obtained from the corresponding Green's function. If the wire is scanned by the contacting STM tip, the conductance as a function of the tip position exhibits oscillations which may change significantly upon increasing the number of wire atoms. Our numerical studies reveal that the conductance depends strongly on whether or not the substrate electrons are localized. As a further ubiquitous feature, we observe the formation of charge oscillations. [ABSTRACT FROM AUTHOR]

Keeping single-qubit quantum coherence above some threshold value not far below unity is a prerequisite for fault-tolerant quantum error correction (QEC). We study the initial dephasing of solid-state qubits in the independent-boson model, which describes well recent experiments on quantum dot (QD) excitons both in bulk and in substrates of reduced geometry such as nanotubes. Using explicit expressions for the exact coherence dynamics, a minimal QEC rate is identified in terms of error threshold, temperature, and qubit-environment coupling strength. This allows us to systematically study the benefit of a current trend towards substrates with reduced dimensions. [ABSTRACT FROM AUTHOR]

Copyright of Ernährung - Wissenschaft Und Praxis is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ernährung - Wissenschaft Und Praxis is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We study numerically the influence of strong Coulomb repulsion on the current through molecular wires that are driven by external electromagnetic fields. The molecule is described by a tight-binding model whose first and last site is coupled to a respective lead. The leads are eliminated within a perturbation theory yielding a master equation for the wire. The decomposition into a Floquet basis enables an efficient treatment of the driving field. For the electronic excitations in bridged molecular wires, we find that strong Coulomb repulsion significantly sharpens resonance peaks which broaden again with increasing temperature. By contrast, it has only a small influence on effects like non-adiabatic electron pumping and coherent current suppression. [ABSTRACT FROM AUTHOR]

Roughly 40% of all patients with insulin-dependent diabetes mellitus (IDDM) develop diabetic nephropathy with proteinuria, hypertension and a decrease in glomerular filtration rate 10 to 20 years after the onset of the disease, and 5 years later most patients suffer from end-stage renal disease. Microalbuminuria, defined as an urinary albumin excretion rate (UAER) between 30 and 300 mg/day, strongly predicts the development of nephropathy in IDDM. Nearly all patients with IDDM, a decreasing glomerular filtration rate and a UAER >300 mg/day have coexisting hypertensive disease additionally worsening renal function. We review the results of recent long-term studies of the current therapeutic management in diabetic patients by means of better blood pressure control, low-protein diet and near-normal blood glucose control in the early microalbuminuric phase as well as in the later phases of the disease characterized by diabetic nephropathy with a UAER >300 mg/day. Since the large majority of studies have been performed on IDDM, our conclusions with regard to therapy are only valid in this subgroup of diabetic patients. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine if pond permanence and vertebrate predation (by fish and waterfowl) affect invertebrate community structure in the mudflat habitat of floodplain ponds. Invertebrate communities were studied for 1 year in four Mississippi River floodplain ponds with different hydroperiods. Pond 1 experienced five dry periods, pond 2 experienced four, pond 3 dried once, and standing water remained in pond 4 for the entire year. Vertebrate predator exclusion treatments (all access, no access, small-fish access and cage controls) were placed in all ponds. As pond duration increased, predatory invertebrate richness and abundance increased while overall invertebrate richness and abundance decreased. With the exception of the cladoceran Diaphanosoma, all commonly encountered taxa were strongly affected by pond permanence in terms of abundance, biomass and, generally, individual biomass. Taxa were nearly early divided between those that were more abundant in less permanent ponds and those that were more abundant in longer-duration ponds. Invertebrate taxa richness, abundance, and total biomass were lower in the all-access treatment than in the treatments that restricted predator access, and these effects were stronger in the more permanent ponds. In general, there were no significant differences in responses to the treatments with small-fish access and no access. These results support models that predict relatively weak effects of predation in frequently disturbed habitats. [ABSTRACT FROM AUTHOR]

A case of a progressive pathologic compression fracture of L2 due to polyostotic fibrous dysplasia is presented. Such unusually severe involvement, requiring decompression and surgical fusion, in the absence of significant recent or remote trauma, has not previously been reported. [ABSTRACT FROM AUTHOR]

Scientific collaborations among nations to address common problems and to build international partnerships as part of science diplomacy is a well-established notion. The international flow of people and ideas has played an important role in the advancement of the 'Sciences' and the current pandemic scenario has drawn attention towards the genuine need for a stronger role of science diplomacy, science advice and science communication. In dealing with the COVID-19 pandemic, visible interactions across science, policy, science communication to the public and diplomacy worldwide have promptly emerged. These interactions have benefited primarily the disciplines of knowledge that are directly informing the pandemic response, while other scientific fields have been relegated. The effects of the COVID-19 pandemic on scientists of all disciplines and from all world regions are discussed here, with a focus on early-career researchers (ECRs), as a vulnerable population in the research system. Young academies and ECR-driven organisations could suggest ECR-powered solutions and actions that could have the potential to mitigate these effects on ECRs working on disciplines not related to the pandemic response. In relation with governments and other scientific organisations, they can have an impact on strengthening and creating fairer scientific systems for ECRs at the national, regional, and global level., Competing Interests: Competing interestsWhile the authors are members or alumni of the GYA, the GYA office staff or GYA funders did not influence the content and discussion presented in this article. The authors declare no competing interests., (© The Author(s) 2021, corrected publication 2021.)