Nanofibrillar networks enable universal assembly of superstructured particle constructs

Superstructured colloidal materials exploit the synergies between components to develop new or enhanced functions. Cohesion is a primary requirement for scaling up these assemblies into bulk materials, and it has only been fulfilled in case-specific bases. Here, we demonstrate that the topology of nanonetworks formed from cellulose nanofibrils (CNFs) enables robust superstructuring with virtually any particle. An intermixed network of fibrils with particles increases the toughness of the assemblies by up to three orders of magnitude compared, for instance, to sintering. Supramolecular cohesion is transferred from the fibrils to the constructs following a power law, with a constant decay factor for particle sizes from 230 nm to 40 μm. Our findings are applicable to other nanofiber dimensions via a rationalization of the morphological aspects of both particles and nanofibers. CNF-based cohesion will move developments of functional colloids from laboratory-scale toward their implementation in large-scale nanomanufacturing of bulk materials.

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Why does the spread of COVID-19 vary greatly in different countries? Revealing the efficacy of face masks in epidemic prevention

Epidemiology and Infection ◽

10.1017/s0950268821000108 ◽

2021 ◽

Vol 149 ◽

Author(s):

Jincheng Wei ◽

Shurui Guo ◽

Enshen Long ◽

Li Zhang ◽

Bizhen Shu ◽

...

Keyword(s):

Social Isolation ◽

Large Scale ◽

Experimental Studies ◽

Weighted Average ◽

Filtration Efficiency ◽

Volume Distribution ◽

Particle Sizes ◽

Economic Activities ◽

Protection Measure ◽

Source Of Infection

Abstract The severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) is highly contagious, and the coronavirus disease 2019 (COVID-19) pandemic caused by it has forced many countries to adopt ‘lockdown’ measures to prevent the spread of the epidemic through social isolation of citizens. Some countries proposed universal mask wearing as a protection measure of public health to strengthen national prevention efforts and to limit the wider spread of the epidemic. In order to reveal the epidemic prevention efficacy of masks, this paper systematically evaluates the experimental studies of various masks and filter materials, summarises the general characteristics of the filtration efficiency of isolation masks with particle size, and reveals the actual efficacy of masks by combining the volume distribution characteristics of human exhaled droplets with different particle sizes and the SARS-CoV-2 virus load of nasopharynx and throat swabs from patients. The existing measured data show that the filtration efficiency of all kinds of masks for large particles and extra-large droplets is close to 100%. From the perspective of filtering the total number of pathogens discharged in the environment and protecting vulnerable individuals from breathing live viruses, the mask has a higher protective effect. If considering the weighted average filtration efficiency with different particle sizes, the filtration efficiencies of the N95 mask and the ordinary mask are 99.4% and 98.5%, respectively. The mask can avoid releasing active viruses to the environment from the source of infection, thus maximising the protection of vulnerable individuals by reducing the probability of inhaling a virus. Therefore, if the whole society strictly implements the policy of publicly wearing masks, the risk of large-scale spread of the epidemic can be greatly reduced. Compared with the overall cost of social isolation, limited personal freedoms and forced suspension of economic activities, the inconvenience for citizens caused by wearing masks is perfectly acceptable.

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Self-aligned integration of native cellulose nanofibrils towards producing diverse bulk materials

Soft Matter ◽

10.1039/c1sm06050c ◽

2011 ◽

Vol 7 (19) ◽

pp. 8804 ◽

Cited By ~ 231

Author(s):

Tsuguyuki Saito ◽

Takehiko Uematsu ◽

Satoshi Kimura ◽

Toshiharu Enomae ◽

Akira Isogai

Keyword(s):

Cellulose Nanofibrils ◽

Bulk Materials ◽

Native Cellulose

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Reversals in the large-scale αΩ-dynamo with memory

Nonlinear Processes in Geophysics ◽

10.5194/npg-22-361-2015 ◽

2015 ◽

Vol 22 (4) ◽

pp. 361-369 ◽

Cited By ~ 1

Author(s):

L. K. Feschenko ◽

G. M. Vodinchar

Keyword(s):

Magnetic Field ◽

Power Law ◽

Geomagnetic Field ◽

Large Scale ◽

Magnetic Polarity ◽

Power Law Model ◽

The Real ◽

Geomagnetic Polarity ◽

With Memory ◽

The Magnetic Field

Abstract. Inversion of the magnetic field in a model of large-scale αΩ-dynamo with α-effect with stochastic memory is under investigation. The model allows us to reproduce the main features of the geomagnetic field reversals. It was established that the polarity intervals in the model are distributed according to the power law. Model magnetic polarity timescale is fractal. Its dimension is consistent with the dimension of the real geomagnetic polarity timescale.

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Citizen workshops in public libraries to disseminate and discuss primary care research results: a scaling-up study

10.21203/rs.3.rs-136811/v1 ◽

2020 ◽

Author(s):

José Massougbodji ◽

Hervé Tchala Vignon Zomahoun ◽

Evehouenou Lionel Adisso ◽

Jasmine Sawadogo ◽

Valérie Borde ◽

...

Keyword(s):

Knowledge Translation ◽

Financial Incentives ◽

General Public ◽

Large Scale ◽

Public Libraries ◽

Scale Up ◽

Scaling Up ◽

Computer Assisted ◽

Knowledge Gain ◽

Research Results

Abstract Background Little is known about engaging patients and stakeholders in the process of scaling up effective knowledge translation interventions targeting the general public. Using an integrated knowledge translation approach, we aimed to scale up and evaluate an effective pilot program of disseminating research results in public libraries. Methods We conducted a scaling-up study targeting the general public. Based on our successful pilot project, we co-developed and implemented a larger-scale program of free citizen workshops in public libraries, this time in close research partnership with stakeholders and patient representatives. Citizen workshops, each facilitated by one participating physician and one science communicator, consisted of a 45-min computer-assisted presentation and a 45-min open exchange. Additional scale-up costs included offering financial incentives to stakeholders involved and the purchase of audio-visual equipment. The intervention outcome was knowledge gained. Scale-up outcomes were satisfaction, appropriateness, coverage, time and costs. An evaluation questionnaire was used to collect data of interest. Both quantitative and qualitative analyses were performed. Results The workshop theme chosen by patient and stakeholder representatives was the high prevalence of medication overuse among people over 65 years of age. From April to May 2019, 26 workshops were given in 25 public libraries reaching 362 people. Eighteen participating physicians and six science communicators facilitated the workshops. Participants reported significant knowledge gain (mean difference 2.1, 95% CI 2.0–2.2, P < .001). Median score for overall public satisfaction was 9/10 (IQR 8–10). A high level of appropriateness of the workshops was globally rated by the public participants Coverage was 92.6% of the total number of public libraries targeted. Costs were $6,051.84 CAD for workshop design and $22,935.41 CAD for scaling them up. Conclusion This project successfully established a large-scale and successful KT bridge between researchers, clinicians, and citizens via public libraries. This study provides a model for a dissemination practice that benefits the general public by both engaging them in the dissemination process and by targeting them directly.

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Effect of porosity and particle size on microwave heating of copper

Science of Sintering ◽

10.2298/sos1002169m ◽

2010 ◽

Vol 42 (2) ◽

pp. 169-182 ◽

Cited By ~ 39

Author(s):

A. Mondal ◽

A. Shukla ◽

A. Upadhyaya ◽

D. Agrawal

Keyword(s):

Particle Size ◽

Particle Sizes ◽

Metallic Materials ◽

Bulk Materials ◽

Microwave Furnace ◽

Particulate Form ◽

Heating Profiles ◽

Powder Compacts ◽

Heating Behavior ◽

Difference Time

The present study investigates the effect of varying particle size and porosity on the heating behavior of a metallic particulate compact in a 2.45GHz multimode microwave furnace. Experiments on copper suggest that unlike monolithic (bulk) materials, metallic materials do couple with microwaves when they are in particulate form. The powder compacts having higher porosity and smaller particle sizes interact more effectively with microwaves and are heated more rapidly. A dynamic electromagnetic-thermal model was developed to simulate the temporal temperature distribution using a 2-D finite difference time domain (FDTD) approach. The model predicts the variation in temperature with time during heating of copper powder compacts. The simulated heating profiles correlate well with those observed from experiments.

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Scaling up: Renewable energy on Aboriginal lands in north west Australia

10.32613/nrp/2021.6 ◽

2021 ◽

Author(s):

Brad Riley

Keyword(s):

Renewable Energy ◽

Large Scale ◽

Scaling Up ◽

Benefit Sharing ◽

Small Community ◽

Renewable Energy Resources ◽

North West ◽

The North ◽

History Of ◽

Aboriginal Lands

This paper examines renewable energy developments on Aboriginal lands in North-West Western Australia at three scales. It first examines the literature developing in relation to large scale renewable energy projects and the Native Title Act (1993)Cwlth. It then looks to the history of small community scale standalone systems. Finally, it examines locally adapted approaches to benefit sharing in remote utility owned networks. In doing so this paper foregrounds the importance of Aboriginal agency. It identifies Aboriginal decision making and economic inclusion as being key to policy and project development in the 'scaling up' of a transition to renewable energy resources in the North-West.

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