Cellulose-based nanofiber membrane fabrication remains a global challenge, especially the use of alternative and sustainable sources of cellulosic materials. Herein, an easy and highly scalable ...cellulose-based nanofiber membrane was successfully fabricated using a solution blow spinning (SBS) method. Such membrane fabrication was carried out with the assistance of an easy-to-spin precursor polymer (i.e. polyacrylonitrile (PAN)). Through this strategy, cellulose acetate (CA) was successfully spun into a ready-to-use membrane. The formation of CA with the PAN nanofiber is concentration-dependent and requires high air pressure to effectively overcome the composite precursor's surface tension and eventually produce nanofibers. Favourable CA concentration in PAN (i.e. 50%-65% v/v CAN/PAN) is important to the formation of sufficient molecular entanglement with PAN in solution. Upon fulfilling the optimized CA concentration, high air pressure (i.e. ≥3 bars) is used to produce jet-like polymeric fibers of PAN dragging off CA, forming numerous nanofibers which are then collected into a substrate forming a membrane. Characterizations of the CA/PAN composite nanofiber were carried out using scanning electron microscopy, Fourier transform infrared, thermogravimetric analysis and differential scanning calorimetry (DSC). Such unique composite nanofiber membranes have potential as filters and adsorbent membranes for air and water/wastewater applications, as well as for biorefinery applications.
Throughout human history, languages have been in competition with each other. As the world becomes more globalized, this trend increases. It affects the decision-making of those in positions of power ...and determines macro language policies and planning. Often decisions about language (or dialects or language variety) are related to usefulness - defined in terms of their pragmatic and commercial currency or their value as symbols of socio-cultural identity. Languages can be modes of entry into coveted social hierarchies or strongholds of religious, historical, technological and political power bases. Languages are seen now as commodities that carry different values in an era of globalization. This volume engages with language policies and positions in relation to the roles and functions these languages adopt. It examines the 'value' of languages, defined in terms of the power they have in the global marketplace as much as within the complex matrices of the local socio-politics. These valuations strongly underpin the various motivations that influence policy-making decisions, and in turn, these motivations create the tensions that characterize many language-related issues; tensions that arise when languages become commodified.
The Australian Geoscience Data Cube (AGDC) aims to realise the full potential of Earth observation data holdings by addressing the Big Data challenges of volume, velocity, and variety that otherwise ...limit the usefulness of Earth observation data. There have been several iterations and AGDC version 2 is a major advance on previous work. The foundations and core components of the AGDC are: (1) data preparation, including geometric and radiometric corrections to Earth observation data to produce standardised surface reflectance measurements that support time-series analysis, and collection management systems which track the provenance of each Data Cube product and formalise re-processing decisions; (2) the software environment used to manage and interact with the data; and (3) the supporting high performance computing environment provided by the Australian National Computational Infrastructure (NCI).
A growing number of examples demonstrate that our data cube approach allows analysts to extract rich new information from Earth observation time series, including through new methods that draw on the full spatial and temporal coverage of the Earth observation archives. To enable easy-uptake of the AGDC, and to facilitate future cooperative development, our code is developed under an open-source, Apache License, Version 2.0. This open-source approach is enabling other organisations, including the Committee on Earth Observing Satellites (CEOS), to explore the use of similar data cubes in developing countries.
•Data-cubes can be used to analyse continental time-series of remote sensing data.•Geometric and spectral corrections are essential for comparability of measurements.•AGDC-v2 uses new tools including NoSQL and netCDF to improve flexibility.•Data-cubes allow new approaches to old problems, such as best pixel mosaics.
Dr Stebbins received the Heidbrink Award, the highest honor of the ADSA, which is presented to the individual who has/had most significantly contributed to the advancement of anesthesiology in ...dentistry, at the 2010 Annual Session. Dr Stebbins was presented with the Louisiana State Dental Association Distinguished Service Award in 2006 for "outstanding service in dentistry and the community," their highest honor. Present in that room were the founding members of the ADSA, including Drs Kinney and Mervis, and a cohesive conglomeration of oral and maxillofacial surgeons, dentist anesthesiologists, and practitioners interested in pain control, sedation, and general anesthesia.
Human ether-à-go-go-related gene (hERG) K(+) channels have unusual gating kinetics. Characterised by slow activation/deactivation but rapid inactivation/recovery from inactivation, the unique gating ...kinetics underlie the central role hERG channels play in cardiac repolarisation. The slow activation and deactivation kinetics are regulated in part by the S4-S5 linker, which couples movement of the voltage sensor domain to opening of the activation gate at the distal end of the inner helix of the pore domain. It has also been suggested that cytosolic domains may interact with the S4-S5 linker to regulate activation and deactivation kinetics. Here, we show that the solution structure of a peptide corresponding to the S4-S5 linker of hERG contains an amphipathic helix. The effects of mutations at the majority of residues in the S4-S5 linker of hERG were consistent with the previously identified role in coupling voltage sensor movement to the activation gate. However, mutations to Ser543, Tyr545, Gly546 and Ala548 had more complex phenotypes indicating that these residues are involved in additional interactions. We propose a model in which the S4-S5 linker, in addition to coupling VSD movement to the activation gate, also contributes to interactions that stabilise the closed state and a separate set of interactions that stabilise the open state. The S4-S5 linker therefore acts as a signal integrator and plays a crucial role in the slow deactivation kinetics of the channel.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
This article examines the role of language selection in constructing the cityscape of highly multilingual, postcolonial places like Malaysia and Namibia. The relationship between language policy, the ...construction of a national identity as well as linguistic inscriptions in the cityscape can be seen as part of language planning in relation to what gets represented, by whom, and for what purpose. We focus on street names as a typical target of language policy. In postcolonial societies, these renegotiations of the cityscape can be analysed against the backdrop of different processes, such as the erasure of names commemorating the colonial past, the inscription of important figures of the newly established nations, or the curation of the language regime with respect to the presence and symbolical function of languages. Using contrastive data and methodology, we analyse the renegotiation of postcolonial cityscapes in Kuala Lumpur (historical city centre, map data, large time span) and Windhoek (entire cityscape, newspaper reports, short time span). Our analysis establishes a notion of how the cityscape as a complex sociosymbolic text is being constantly rewritten by its actors. We find different motives attached to such processes of cultural representation, including national identity building and ideological consolidation of the cityscape.
To determine and compare the accuracy and reliability of shade matching using the conventional and smartphone virtual methods.
A phantom head with both maxillary central incisors removed was set up. ...A central incisor of various standard shades was inserted into the phantom head. Five undergraduate and five postgraduate students were asked to select the closest shade to match the central incisor using the Vita Classic shade guide. The procedure was then repeated using images taken by a smartphone. Each technique was repeated three times. Differences in accuracy of shade matching between the two techniques for every shade tab and between undergraduate and postgraduate dental students were compared using chi-square statistical analysis. The P value was set at .001. Differences in intra-rater and inter-rater reliability between the two techniques and among the three sessions were compared using paired t test and analysis of variance (ANOVA), respectively, with a P value of .05. The reliability of both techniques was further measured using Cohen kappa statistical test.
The smartphone virtual shade-matching technique showed significantly higher accuracy in shade matching with most of the tested shade tabs than the conventional method (P < .001), irrespective of observers' clinical experience. Higher repeatability was found in the virtual technique than the conventional technique, with higher intra-rater and inter-rater reliability observed.
Smartphone virtual shade matching showed better accuracy and reliability than the conventional method and could be used as an alternative shade-matching method.
Ultrasound-guided scalp blocks may revolutionize regional anesthesia for neurosurgery. In this report, we demonstrate that ultrasound-guided scalp blocks can be used effectively for a craniotomy. A ...48-year-old patient with a brain tumor at the motor cortex was scheduled for an awake craniotomy. Ultrasound-guided scalp blocks targeting the bilateral supraorbital, supratrochlear, zygomaticotemporal, auriculotemporal, greater auricular, lesser occipital, greater occipital, and third occipital nerves were performed. A total of 29 mL of levobupivacaine 0.3% was used. No additional local anesthetic agent was given for skull pinning, skin incision, or the craniotomy. Postoperatively, the patient remained pain-free, and she was discharged without complications.
Plant fibers have been studied as sources of nanocellulose due to their sustainable features. This study investigated the effects of acid hydrolysis parameters, reaction temperature, and acid ...concentration on nanocellulose yield from maguey (
) fiber. Nanocellulose was produced from the fibers via the removal of non-cellulosic components through alkali treatment and bleaching, followed by strong acid hydrolysis for 45 min using sulfuric acid (H
SO
). The temperature during acid hydrolysis was 30, 40, 50, and 60 °C, and the H
SO
concentration was 40, 50, and 60 wt. % H
SO
. Results showed that 53.56% of raw maguey fibers were isolated as cellulose, that is, 89.45% was α-cellulose. The highest nanocellulose yield of 81.58 ± 0.36% was achieved from acid hydrolysis at 50 °C using 50 wt. % H
SO
, producing nanocellulose measuring 8-75 nm in diameter and 72-866 nm in length, as confirmed via field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) analysis. Fourier-transform infrared spectroscopy (FTIR) analysis indicated the chemical transformation of fibers throughout the nanocellulose production process. The zeta potential analysis showed that the nanocellulose had excellent colloidal stability with a highly negative surface charge of -37.3 mV. Meanwhile, X-ray diffraction (XRD) analysis validated the crystallinity of nanocellulose with a crystallinity index of 74.80%. Lastly, thermogravimetric analysis (TGA) demonstrated that the inflection point attributed to the cellulose degradation of the produced nanocellulose is 311.41 °C.
The notion of style has received extensive attention under the rubric of stylistics. There, the focus has been strongly, though not exclusively, on literary texts. Particular stylistic choices or ...patterns of stylistic choices have been deemed to be significant or foregrounded and this is said to allow the reader to reach grounded interpretations of the texts.
PDF
