3,236 research outputs found
Experience in feeding coal into a liquefaction process development unit
A system for preparing coal slurry and feeding it into a high pressure liquefaction plant is described. The system was developed to provide supporting research and development for the Bureau of Mines coal liquefaction pilot plant. Operating experiences are included
A review on removal of pharmaceuticals from water by adsorption
Pharmaceuticals and personal care products are recognized as emerging pollutants in water resources. Various treatment options have been investigated for the removal of pharmaceuticals that include both conventional (e.g., biodegradation, adsorption, activated sludge) and advanced (e.g., membrane, microfiltration, ozonation) processes. This article reviews literature for adsorptive removal of pharmaceuticals from water sources. Adsorbents from various origins were reviewed for their capacity to remove pharmaceuticals from water. These adsorbents include carbonaceous materials, clay minerals, siliceous adsorbents, and polymeric materials. The adsorption capacity of adsorbents to adsorb pharmaceuticals from water is discussed in this study. The review discusses the mechanism for adsorption of pharmaceuticals onto adsorbents as well. Finally, effectiveness of processing parameters during adsorption processes is presented
Proximal humeral fractures with a severe varus deformity treated by fixation with a locking plate
Influence of Natural Zeolite and Mineral additive on Bacterial Self-healing Concrete: A Review
With time, the development of micro-cracks in concrete is a frequently reported problem in the structures due to the ingress of harmful substances, leading to the degradation of its quality and strength, which ultimately declines the construction. The present work is a review paper based on enhancing the self-healing property of concrete by inducing different bacteria alone or incorporating different mineral additives. It has been seen that various rehabilitated methodologies are in queue to surmount concrete’s weaknesses and to increase its strength and durability. The latest methodology includes using non-pathogenic microbes in concrete as Microbial induced Calcium Carbonate Precipitation (MICCP). The property of precipitating calcium carbonate (CaCO3) crystals by their metabolic activities helps repair the cracks in harsh conditions and improve their strength. Ureolytic bacteria like Bacillus pasteurii/Sporosarcina pasteurii, Bacillus subtilis, Bacillus megaterium, etc., have a specific property by which they can excite urea when integrated with a calcium source and help in sealing the cracks by CaCO3 precipitation. Different studies have observed that specimens having a bacterial concentration of 105-107 cells/ml with Natural Zeolite (NZ) replacement (10%) represents better interaction of the microstructure of concrete because of the formation of calcium silicate hydrate (CSH) gel. Further, the reduction in CH bond with reduced pore space has also been observed. NZ alone enhances micro-structural property, but it shows CaCo3 precipitation and more densification of microstructure under bacterial combination. XRD also confirms an increase in the calcite composition when the bacterial concentration of 105-107 cells/ml is used. The overall properties of standard and high-strength bacterial concrete (105-107 cells/ml) with 10% Natural Zeolite replacement can provide a better option for the future of sustained and strong concrete. Doi: 10.28991/CEJ-2022-08-05-015 Full Text: PD
False-positive troponin elevation due to an immunoglobulin-G-cardiac troponin T complex: a case report.
Background: Troponin is a crucial biomarker for the diagnosis of an acute coronary syndrome (ACS). It rises in response to myocardial injury from significant acute myocardial ischaemia caused by obstructive coronary artery disease ['classical' myocardial infarction (MI)]. However, raised levels have also been noted in conditions not recognized as classical ACS. This may include MI with non-obstructed coronary arteries such as takotsubo cardiomyopathy and other acute or chronic conditions such as pulmonary embolus or chronic kidney disease. This is commonly labelled as a 'falsely elevated' troponin although there is some myocardial strain to explain the rise, such as an increase in cardiac oxygen demand. True 'falsely elevated' troponin, characterized by a persistent elevation in the absence of cardiac injury does occur and thought to be secondary to an immunoglobulin-troponin complex (macrotroponin). Case summary: A 53-year-old gentleman with a background of diabetes, hypertension, hypercholesterolaemia, and hepatitis B was admitted with chest pain and persistently elevated cardiac troponin T (cTnT) levels. Investigations revealed unobstructed coronary arteries and a structurally normal, well-functioning heart. Subsequent biochemical analysis found the persistently elevated cTnT secondary to macrotroponin T. Discussion: Macrotroponin, an immunoglobulin-troponin bound complex should be considered as a differential diagnosis when the biochemistry is not reflective of the clinical picture. Early recognition requires effective collaboration with the biochemistry laboratory for accurate diagnosis
Acalypha indica Linn is a potential source of root-knot nematode infestation in cultivated fields
Acalypha indica L. is a commonly growing weed in India, which is also known as Indian Acalypha. These plants were growing as a weed in pots wherein okra was planted for experimental purpose. Infestation of the root-knot nematode, Meloidogyne incognita was observed on it. Soil and root samples were collected for analyses of nematode infestation. Roots of the infested plants were galled measuring gall index (GI) of 3-4. The population density of second stage juveniles (J2) in soil varies from 378-752/200cc soil and the roots were harboring 3876-7654 eggs/per root system. The root galling and presence of high population of nematode eggs and J2 revealed that A. indica can be a reservoir for M. incognita during non-host cropping and serve as a source of infestation to other hosts in the next cropping season. So, in the light of present findings growers are advised to be watchful for A. indica in their fields, and keep the field free from this weed to minimize the infestation of M. incognita in the next crop.
Is This Really You? An Empirical Study on Risk-Based Authentication Applied in the Wild
Risk-based authentication (RBA) is an adaptive security measure to strengthen
password-based authentication. RBA monitors additional implicit features during
password entry such as device or geolocation information, and requests
additional authentication factors if a certain risk level is detected. RBA is
recommended by the NIST digital identity guidelines, is used by several large
online services, and offers protection against security risks such as password
database leaks, credential stuffing, insecure passwords and large-scale
guessing attacks. Despite its relevance, the procedures used by
RBA-instrumented online services are currently not disclosed. Consequently,
there is little scientific research about RBA, slowing down progress and deeper
understanding, making it harder for end users to understand the security
provided by the services they use and trust, and hindering the widespread
adoption of RBA.
In this paper, with a series of studies on eight popular online services, we
(i) analyze which features and combinations/classifiers are used and are useful
in practical instances, (ii) develop a framework and a methodology to measure
RBA in the wild, and (iii) survey and discuss the differences in the user
interface for RBA. Following this, our work provides a first deeper
understanding of practical RBA deployments and helps fostering further research
in this direction.Comment: 14 pages, 7 table
Cereal root exudates contain highly structurally complex polysaccharides with soil‐binding properties
Rhizosheaths function in plant−soil interactions, and are proposed to form due to a mix of soil particle entanglement in root hairs and the action of adhesive root exudates. The soil‐binding factors released into rhizospheres to form rhizosheaths have not been characterised. Analysis of the high‐molecular‐weight (HMW) root exudates of both wheat and maize plants indicate the presence of complex, highly branched polysaccharide components with a wide range of galactosyl, glucosyl and mannosyl linkages that do not directly reflect cereal root cell wall polysaccharide structures. Periodate oxidation indicates that it is the carbohydrate components of the HMW exudates that have soil‐binding properties. The root exudates contain xyloglucan (LM25), heteroxylan (LM11/LM27) and arabinogalactan‐protein (LM2) epitopes, and sandwich‐ELISA evidence indicates that, in wheat particularly, these can be interlinked in multi‐polysaccharide complexes. Using wheat as a model, exudate‐binding monoclonal antibodies have enabled the tracking of polysaccharide release along root axes of young seedlings, and their presence at root hair surfaces and in rhizosheaths. The observations indicate that specific root exudate polysaccharides, distinct from cell wall polysaccharides, are adhesive factors secreted by root axes, and that they contribute to the formation and stabilisation of cereal rhizosheaths
DLTS and in situ C–V analysis of trap parameters in swift 50 MeV Li3+ ion-irradiated Ni/SiO2/Si MOS capacitors
Ni/SiO2/Si MOS structures were fabricated on n-type Si wafers and were irradiated with 50 MeV Li3+ ions with fluences ranging from 1×1010 to 1×1012 ions/cm2. High frequency C–V characteristics are studied in situ to estimate the build-up of fixed and oxide charges. The nature of the charge build-up with ion fluence is analyzed. Defect levels in bulk Si and its properties such as activation energy, capture cross-section, trap concentration and carrier lifetimes are studied using deep-level transient spectroscopy. Electron traps with energies ranging from 0.069 to 0.523 eV are observed in Li ion-irradiated devices. The dependence of series resistance, substrate doping and accumulation capacitance on Li ion fluence are clearly explained. The study of dielectric properties (tan δ and quality factor) confirms the degradation of the oxide layer to a greater extent due to ion irradiation
Alanine scanning mutagenesis of a high-affinity nitrate transporter highlights the requirement for glycine and asparagine residues in the two nitrate signature motifs
Common to all of the nitrate nitrite porter family are two conserved motifs in transmembrane helices 5 and 11 termed NS (nitrate signature) 1 and NS2. Although perfectly conserved substrate-interacting arginine residues have been described in transmembrane helices 2 and 8, the role of NSs has not been investigated. In the present study, a combination of structural modelling of NrtA (nitrate transporter from Aspergillus nidulans) with alanine scanning mutagenesis of residues within and around the NSs has been used to shed light on the probable role of conserved residues in the NSs. Models show that Asn 168 in NS1 and Asn 459 in NS2 are positioned approximately midway within the protein at the central pivot point in close proximity to the substrate-binding residues Arg 368 and Arg 87 respectively, which lie offset from the pivot point towards the cytoplasmic face. The Asn 168 /Arg 368 and Asn 459 /Arg 87 residue pairs are relatively widely separated on opposite sides of the probable substrate translocation pore. The results of the present study demonstrate the critical structural contribution of several glycine residues in each NS at sites of close helix packing. Given the relative locations of Asn 168 /Arg 368 and Asn 459 /Arg 87 pairs, the validity of the models and possible role of the NSs together with the substrate-binding arginine residues are discusse
- …