279 research outputs found
Jetted mixtures of particle suspensions and resins
This is the author accepted manuscript. The final version is available from AIP at http://scitation.aip.org/content/aip/journal/pof2/26/10/10.1063/1.4897238.Drop-on-demand (DoD) ink-jetting of hard particle suspensions with volume fraction Φ ~ 0.25 has been surveyed using 1000 ultra-high speed videos as a function of particle size (d90 = 0.8-3.6 µm), with added 2 wt% acrylic (250 kDa) or 0.5 wt% cellulose (370 kDa) resin, and also compared with Newtonian analogues. Jet break-off times from 80 µm diameter nozzles were insensitive (120±10 µs) to particle size, and resin jet break-off times were not significantly altered by > 30 wt% added particles. Different particle size grades can be jetted equally well in practice, while resin content effectively controls DoD break-off times
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TruMet: An approach towards computing trust in multi-agent environment.
The growing popularity of multi-agent based
approaches towards the formation and operation of virtual
organizations (VO) present over the Internet, offer both
opportunities and risks. One of the risks involved in such
community is in the identification of trustworthy agent partners
for transaction. In this paper we aim to describe our trust model
which would contribute in measuring trust in the interacting
agents. Named as TruMet, the trust metric model works on the
basis of the parameters that we have identified as relevant to the
features of the community. The model primarily analyses trust
value on the basis of the agent¿s reputation, as provided by the
agent itself, and the agent¿s aggregate rating as provided by the
witness agents. The final computation of the trust value is given
by a weighted average of these two components. While
computing the aggregate rating, a weight based method has been
adopted to discount the contribution of possibly un-fair ratings
by the witness agents
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How Does Schooling Influence Maternal Health Practices? Evidence from Nepal
Encapsulation-free controlled release: Electrostatic adsorption eliminates the need for protein encapsulation in PLGA nanoparticles
Encapsulation of therapeutic molecules within polymer particles is a well-established method for achieving
controlled release, yet challenges such as low loading, poor encapsulation efficiency, and loss of protein activity
limit clinical translation. Despite this, the paradigm for the use of polymer particles in drug delivery has remained
essentially unchanged for several decades. By taking advantage of the adsorption of protein therapeutics
to poly(lactic-co-glycolic acid) (PLGA) nanoparticles, we demonstrate controlled release without
encapsulation. In fact, we obtain identical, burst-free, extended-release profiles for three different protein therapeutics
with and without encapsulation in PLGA nanoparticles embedded within a hydrogel. Using both positively
and negatively charged proteins, we show that short-range electrostatic interactions between the
proteins and the PLGA nanoparticles are the underlying mechanism for controlled release. Moreover, we demonstrate
tunable release by modifying nanoparticle concentration, nanoparticle size, or environmental pH. These
new insights obviate the need for encapsulation and offer promising, translatable strategies for a more effective
delivery of therapeutic biomolecules
European Stroke Organisation (ESO) guideline on screening for subclinical atrial fibrillation after stroke or transient ischaemic attack of undetermined origin
We aimed to provide practical recommendations for the screening of subclinical atrial fibrillation (AF) in patients with ischaemic stroke or transient ischaemic attack (TIA) of undetermined origin. These guidelines are based on the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) methodology. Five relevant Population, Intervention, Comparator, Outcome questions were defined by a multidisciplinary module working group (MWG). Longer duration of cardiac rhythm monitoring increases the detection of subclinical AF, but the optimal monitoring length is yet to be defined. We advise longer monitoring to increase the rate of anticoagulation, but whether longer monitoring improves clinical outcomes needs to be addressed. AF detection does not differ from in- or out-patient ECG-monitoring with similar monitoring duration, so we consider it reasonable to initiate in-hospital monitoring as soon as possible and continue with outpatient monitoring for more than 48 h. Although insertable loop recorders (ILR) increase AF detection based on their longer monitoring duration, comparison with non-implantable ECG devices for similar monitoring time is lacking. We suggest the use of implantable devices, if feasible, for AF detection instead of non-implantable devices to increase the detection of subclinical AF. There is weak evidence of a useful role for blood, ECG and brain imaging biomarkers for the identification of patients at high risk of AF. In patients with patent foramen ovale, we found insufficient evidence from RCT, but prolonged cardiac monitoring in patients >55 years is advisable for subclinical AF detection. To conclude, in adult patients with ischaemic stroke or TIA of undetermined origin, we recommend longer duration of cardiac rhythm monitoring of more than 48 h and if feasible with IRL to increase the detection of subclinical AF
SCIMP is a spatiotemporal transmembrane scaffold for Erk1/2 to direct pro-inflammatory signaling in TLR-activated macrophages
Immune cells are armed with Toll-like receptors (TLRs) for sensing and responding to pathogens and other danger cues. The role of extracellular-signal-regulated kinases 1/2 (Erk1/2) in TLR signaling remains enigmatic, with both pro- and anti-inflammatory functions described. We reveal here that the immune-specific transmembrane adaptor SCIMP is a direct scaffold for Erk1/2 in TLR pathways, with high-resolution, live-cell imaging revealing that SCIMP guides the spatial and temporal recruitment of Erk2 to membrane ruffles and macropinosomes for pro-inflammatory TLR4 signaling. SCIMP-deficient mice display defects in Erk1/2 recruitment to TLR4, c-Fos activation, and pro-inflammatory cytokine production, with these effects being phenocopied by Erk1/2 signaling inhibition. Our findings thus delineate a selective role for SCIMP as a key scaffold for the membrane recruitment of Erk1/2 kinase to initiate TLR-mediated pro-inflammatory responses in macrophages
New ternary blend strategy based on a vertically self-assembled passivation layer enabling efficient and photostable inverted organic solar cells
Herein, a new ternary strategy to fabricate efficient and photostable inverted organic photovoltaics (OPVs) is introduced by combining a bulk heterojunction (BHJ) blend and a fullerene self-assembled monolayer (C60 -SAM). Time-of-flight secondary-ion mass spectrometry - analysis reveals that the ternary blend is vertically phase separated with the C60 -SAM at the bottom and the BHJ on top. The average power conversion efficiency - of OPVs based on the ternary system is improved from 14.9% to 15.6% by C60 -SAM addition, mostly due to increased current density (Jsc ) and fill factor -. It is found that the C60 -SAM encourages the BHJ to make more face-on molecular orientation because grazing incidence wide-angle X-ray scattering - data show an increased face-on/edge-on orientation ratio in the ternary blend. Light-intensity dependent Jsc data and charge carrier lifetime analysis indicate suppressed bimolecular recombination and a longer charge carrier lifetime in the ternary system, resulting in the enhancement of OPV performance. Moreover, it is demonstrated that device photostability in the ternary blend is enhanced due to the vertically self-assembled C60 -SAM that successfully passivates the ZnO surface and protects BHJ layer from the UV-induced photocatalytic reactions of the ZnO. These results suggest a new perspective to improve both performance and photostability of OPVs using a facial ternary method
Does COVID-19 contribute to development of neurological disease?
Background: Although coronavirus disease 2019 (COVID-19) has been associated primarily with pneumonia, recent data show that the causative agent of COVID-19, the coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), can infect a large number of vital organs beyond the lungs, such as the heart, kidneys, and the brain. Thus, there is evidence showing possible retrograde transmission of the virus from the olfactory epithelium to regions of the brain stem. Methods: This is a literature review article. The research design method is an evidence-based rapid review. The present discourse aim is first to scrutinize and assess the available literature on COVID-19 repercussion on the central nervous system (CNS). Standard literature and database searches were implemented, gathered relevant material, and extracted information was then assessed. Results: The angiotensin-converting enzyme 2 (ACE2) receptors being the receptor for the virus, the threat to the central nervous system is expected. Neurons and glial cells express ACE2 receptors in the CNS, and recent studies suggest that activated glial cells contribute to neuroinflammation and the devastating effects of SARS-CoV-2 infection on the CNS. The SARS-CoV-2-induced immune-mediated demyelinating disease, cerebrovascular damage, neurodegeneration, and depression are some of the neurological complications discussed here. Conclusion: This review correlates present clinical manifestations of COVID-19 patients with possible neurological consequences in the future, thus preparing healthcare providers for possible future consequences of COVID-19
Simulations of extensional flow in microrheometric devices
We present a detailed numerical study of the flow of a Newtonian fluid through microrheometric devices featuring a sudden contraction–expansion. This flow configuration is typically used to generate extensional deformations and high strain rates. The excess pressure drop resulting from the converging and diverging flow is an important dynamic measure to quantify if the device is intended to be used as a microfluidic extensional rheometer. To explore this idea, we examine the effect of the contraction length, aspect ratio and Reynolds number on the flow kinematics and resulting pressure field. Analysis of the computed velocity and pressure fields show that, for typical experimental conditions used in microfluidic devices, the steady flow is highly three-dimensional with open spiraling vortical structures in the stagnant corner regions. The numerical simulations of the local kinematics and global pressure drop are in good agreement with experimental results. The device aspect ratio is shown to have a strong impact on the flow and consequently on the excess pressure drop, which is quantified in terms of the dimensionless Couette and Bagley correction factors. We suggest an approach for calculating the Bagley correction which may be especially appropriate for planar microchannels
From Loom to Machine: Tibetan Aprons and the Configuration of Place
In this paper I examine how objects become connected to place in complex and contradictory ways. Over the past ten to fi fteen years, rapid transformations in Chinese manufacturing and transportation networks have signifi cantly altered the production, marketing, and consumption of commodities made in the Tibet Autonomous Region and traded in Kalimpong, India, and Kathmandu, Nepal. In an attempt to connect the ethnographic study of material culture with more macrolevel processes of geoeconomic change, I begin the piece with an examination of the changing production, materials, and styles of a very specifi c commodity, the Tibetan women’s apron. I then explore traders’ narratives about the values of handmade, machine-made, wool, and synthetic commodities, arguing that we ought to look beyond dichotomies of ‘old’ versus ‘new’ or ‘authentic’ versus ‘inauthentic’ objects to show in detail how the attachment of commodities to representations of place fi gures importantly in the contemporary study both of globalization and uneven development. Finally, I suggest that Karl Marx’s notion of dead labor is useful in analyzing the recent move towards the revitalization of Tibetan wool for both the domestic Chinese industry and the global tourist industry
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