DNA Origami Rotaxanes: Tailored Synthesis and Controlled Structure Switching

Mechanically interlocked supramolecular assemblies are appealing building blocks for creating functional nanodevices. Herein, we describe the multistep assembly of large DNA origami rotaxanes that are capable of programmable structural switching. We validated the topology and structural integrity of these rotaxanes by analyzing the intermediate and final products of various assembly routes by electrophoresis and electron microscopy. We further analyzed two structureâ switching behaviors of our rotaxanes, which are both mediated by DNA hybridization. In the first mechanism, the translational motion of the macrocycle can be triggered or halted at either terminus. In the second mechanism, the macrocycle can be elongated after completion of the rotaxane assembly, giving rise to a unique structure that is otherwise difficult to access.A new set of threads: Rotaxanes with a length of up to 200â nm were assembled by a DNA origami approach. The threaded macrocycles can be programmably docked at either dumbbell stopper, and the assemblies can be reconfigured to generate new, otherwise unfavorable rotaxane topologies.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/137326/1/anie201604621_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/137326/2/anie201604621-sup-0001-misc_information.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/137326/3/anie201604621.pd

Accelerated Multi-Organization Conflict Resolution

In this paper, we discuss two situations where two organizations with different aims recognized the dysfunctionality of their relationship. In each of these cases, which were long running (6–8 months), the organizations had worked hard to resolve this dysfunctionality, and conflict, by organizing off-site meetings designed to resolve the conflict. These 1-day meetings failed. Subsequently Group Support System workshops were used for 1 day workshops and in each case the conflict was essentially resolved within 55 min. The research reported in this paper seeks to answer the question: what happened in these cases that led to a resolution of the conflict in such a short time period, given other attempts had failed? Specifically the paper explores the impact of the GSS used to facilitate two organizations seeking to resolve a conflictual situation

Construction of a Holliday Junction in Small Circular DNA Molecules for Stable Motifs and Twoâ Dimensional Lattices

Design rules for DNA nanotechnology have been mostly learnt from using linear singleâ stranded (ss) DNA as the source material. For example, the core structure of a typical DAO (double crossover, antiparallel, odd halfâ turns) tile for assembling 2D lattices is constructed from only two linear ssâ oligonucleotide scaffold strands, similar to two ropes making a square knot. Herein, a new type of coupled DAO (cDAO) tile and 2D lattices of small circular ssâ oligonucleotides as scaffold strands and linear ssâ oligonucleotides as staple strands are reported. A cDAO tile of cDAOâ c64nt (c64nt: circular 64 nucleotides), shaped as a solid parallelogram, is constructed with a Holliday junction (HJ) at the center and two HJs at both poles of a c64nt; similarly, cDAOâ c84nt, shaped as a crossed quadrilateral composed of two congruent triangles, is formed with a HJ at the center and four threeâ way junctions at the corners of a c84nt. Perfect 2D lattices were assembled from cDAO tiles: infinite nanostructures of nanoribbons, nanotubes, and nanorings, and finite nanostructures. The structural relationship between the visible lattices imaged by AFM and the corresponding invisible secondary and tertiary molecular structures of HJs, inclination angle of hydrogen bonds against the doubleâ helix axis, and the chirality of the tile can be interpreted very well. This work could shed new light on DNA nanotechnology with unique circular tiles.Bending the rules: The design of DNA motifs and lattices has mostly been investigated by using linear singleâ stranded DNA molecules as source materials. New coupled DAO (double crossover, antiparallel, odd halfâ turns) motifs and lattices have been constructed from small circular DNA molecules as scaffolds.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/144626/1/cbic201800122.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/144626/2/cbic201800122_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/144626/3/cbic201800122-sup-0001-misc_information.pd

Negotiation in strategy making teams : group support systems and the process of cognitive change

This paper reports on the use of a Group Support System (GSS) to explore at a micro level some of the processes manifested when a group is negotiating strategy-processes of social and psychological negotiation. It is based on data from a series of interventions with senior management teams of three operating companies comprising a multi-national organization, and with a joint meeting subsequently involving all of the previous participants. The meetings were concerned with negotiating a new strategy for the global organization. The research involved the analysis of detailed time series data logs that exist as a result of using a GSS that is a reflection of cognitive theory

Host-Associated Bacteriophage Isolation and Preparation for Viral Metagenomics.

Prokaryotic viruses, or bacteriophages, are viruses that infect bacteria and archaea. These viruses have been known to associate with host systems for decades, yet only recently have their influence on the regulation of host-associated bacteria been appreciated. These studies have been conducted in many host systems, from the base of animal life in the Cnidarian phylum to mammals. These prokaryotic viruses are useful for regulating the number of bacteria in a host ecosystem and for regulating the strains of bacteria useful for the microbiome. These viruses are likely selected by the host to maintain bacterial populations. Viral metagenomics allows researchers to profile the communities of viruses associating with animal hosts, and importantly helps to determine the functional role these viruses play. Further, viral metagenomics show the sphere of viral involvement in gene flow and gene shuffling in an ever-changing host environment. The influence of prokaryotic viruses could, therefore, have a clear impact on host health

Metagenomic Analysis of Lysogeny in Tampa Bay: Implications for Prophage Gene Expression

Phage integrase genes often play a role in the establishment of lysogeny in temperate phage by catalyzing the integration of the phage into one of the host's replicons. To investigate temperate phage gene expression, an induced viral metagenome from Tampa Bay was sequenced by 454/Pyrosequencing. The sequencing yielded 294,068 reads with 6.6% identifiable. One hundred-three sequences had significant similarity to integrases by BLASTX analysis (e≤0.001). Four sequences with strongest amino-acid level similarity to integrases were selected and real-time PCR primers and probes were designed. Initial testing with microbial fraction DNA from Tampa Bay revealed 1.9×107, and 1300 gene copies of Vibrio-like integrase and Oceanicola-like integrase L−1 respectively. The other two integrases were not detected. The integrase assay was then tested on microbial fraction RNA extracted from 200 ml of Tampa Bay water sampled biweekly over a 12 month time series. Vibrio-like integrase gene expression was detected in three samples, with estimated copy numbers of 2.4-1280 L−1. Clostridium-like integrase gene expression was detected in 6 samples, with estimated copy numbers of 37 to 265 L−1. In all cases, detection of integrase gene expression corresponded to the occurrence of lysogeny as detected by prophage induction. Investigation of the environmental distribution of the two expressed integrases in the Global Ocean Survey Database found the Vibrio-like integrase was present in genome equivalents of 3.14% of microbial libraries and all four viral metagenomes. There were two similar genes in the library from British Columbia and one similar gene was detected in both the Gulf of Mexico and Sargasso Sea libraries. In contrast, in the Arctic library eleven similar genes were observed. The Clostridium-like integrase was less prevalent, being found in 0.58% of the microbial and none of the viral libraries. These results underscore the value of metagenomic data in discovering signature genes that play important roles in the environment through their expression, as demonstrated by integrases in lysogeny

Strategic options development and analysis

Strategic Options Development and Analysis (SODA) enables a group or individual to construct a graphical representation (map) or a problematic situation, and thus explore options and their ramifications with respect to a complex system of goals or objectives. In addition the approach aims to help groups arrive at a negotiated agreement about how to act to resolve the situation. It is based upon the use of causal mapping – a formally constructed means-ends network. Because the map has been constructed using the natural language of the problem owners it becomes a model of the situation that is ‘owned’ by those who define the problem. The use of formalities for the construction of the model makes it amenable to a range of analyses encouraging reflection and a deeper understanding. These analyses can be used in a ‘rough and ready’ manner by visual inspection or through the use of specialist causal mapping software. Each of the analyses helps a group or individual discover important features of the problem situation. And these features facilitate agreeing a good solution. The SODA process is aimed at helping a group learn about the situation they face before they reach agreements. Most significantly the exploration through the causal map leads to a higher probability of more creative solutions and promotes solutions that are more likely to be implemented because the problem construction process is more likely to include richer social dimensions about the blockages to action and organizational change. The basic theories that inform SODA derive from cognitive psychology and social negotiation, where the model acts as a continuously changing representation of the problematic situation (a transitional object) – changing as the views of a person or group shift through learning and exploration. This chapter jointly written by two leading practitioner academics and the original developers of SODA, Colin Eden and Fran Ackermann, describe the SODA approach as it is applied in practice

Effects of vacuum packaging on the physical quality of minimally processed potatoes

In recent years, consumers have become more health conscious in their food choices but they also have less time to prepare healthy meals. As a result, minimally processed (MP) products have become an important sector of the food industry because of their ‘fresh-like’ qualities, convenience and speed of meal preparation. In this study, the physical qualities of MP potatoes (‘Désirée’ variety) stored for 7 days in vacuum packaging were evaluated. The shelf life of MP potatoes was effectively extended to nearly 1 week under refrigerated storage by using vacuum packaging systems. The main quality parameters were constant during storage

Effect of lifestyle intervention for people with diabetes or prediabetes in real-world primary care: propensity score analysis

<p>Abstract</p> <p>Background</p> <p>Many lifestyle interventions for patients with prediabetes or type 2 diabetes mellitus (T2DM) have been investigated in randomised clinical trial settings. However, the translation of these programmes into primary care seems challenging and the prevalence of T2DM is increasing. Therefore, there is an urgent need for lifestyle programmes, developed and shown to be effective in real-world primary care. We evaluated a lifestyle programme, commissioned by the Dutch government, for patients with prediabetes or type 2 diabetes in primary care.</p> <p>Methods</p> <p>We performed a retrospective comparative medical records analysis using propensity score matching. Patients with prediabetes or T2DM were selected from ten primary healthcare centres. Patients who received the lifestyle intervention (n = 186) were compared with a matched group of patients who received usual care (n = 2632). Data were extracted from the electronic primary care records. Propensity score matching was used to control for confounding by indication. Outcome measures were exercise level, BMI, HbA1c, fasting glucose, systolic and diastolic blood pressure, total cholesterol, HDL and LDL cholesterol and triglycerides and the follow-up period was one year.</p> <p>Results</p> <p>There was no significant difference at follow-up in any outcome measure between either group. The reduction at one year follow-up of HbA1c and fasting glucose was positive in the intervention group compared with controls, although not statistically significant (-0.12%, <it>P </it>= 0.07 and -0.17 mmol/l, <it>P </it>= 0.08 respectively).</p> <p>Conclusions</p> <p>The effects of the lifestyle programme in real-world primary care for patients with prediabetes or T2DM were small and not statistically significant. The attention of governments for lifestyle interventions is important, but from the available literature and the results of this study, it must be concluded that improving lifestyle in real-world primary care is still challenging.</p

Single Spin Asymmetry ANA_N in Polarized Proton-Proton Elastic Scattering at s=200\sqrt{s}=200 GeV

We report a high precision measurement of the transverse single spin asymmetry $A_N$ at the center of mass energy $\sqrt{s}=200$ GeV in elastic proton-proton scattering by the STAR experiment at RHIC. The $A_N$ was measured in the four-momentum transfer squared $t$ range $0.003 \leqslant |t| \leqslant 0.035$ \GeVcSq, the region of a significant interference between the electromagnetic and hadronic scattering amplitudes. The measured values of $A_N$ and its $t$-dependence are consistent with a vanishing hadronic spin-flip amplitude, thus providing strong constraints on the ratio of the single spin-flip to the non-flip amplitudes. Since the hadronic amplitude is dominated by the Pomeron amplitude at this $\sqrt{s}$, we conclude that this measurement addresses the question about the presence of a hadronic spin flip due to the Pomeron exchange in polarized proton-proton elastic scattering.Comment: 12 pages, 6 figure