We report temperature-dependent dielectric permittivity, thermal conductivity and mechanical resonances of as-grown hybrid perovskite single crystal CH
3
NH
3
PbBr
3
. Structural phase transitions ...are analysed using new experimental techniques, where thermal conductivity by steady-state process and elastic modulai by ultra-resonance spectroscopy is carried out through 100 and 110 directions, respectively. Performing thermal conductivity measurement on small-sized samples usually pose a significant challenge due to its dimensional limit. Following the steady-state technique, we measured the thermal conductivity of around 1 W m
−1
K
−1
in the temperature range 100–300 K on 2 × 2 mm
2
size crystal. This is found to be comparable with I
+3
anion-based hybrid perovskites as reported by Pisoni
et al
2014
J. Phys. Chem. Lett.
5
2488. Room temperature electrical resistivity and dielectric permittivity of order 10
9
and 10
2
, respectively, shows sharp transitions while approaching 150 K, which strongly supports first-order structural transition. Thermally activated resistivity behaviour above 280 K follows 1/
T
dependence, yielding activation energy of 0.2 eV. Softening of elastic moduli on approaching the phase transition is analysed from resonant ultrasound spectroscopy measurement. Square of the resonance frequency is found to diverge below 236 K, which inhibits any further experimental determination of elastic moduli at low temperature.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Background
Oropharyngeal dysphagia (OD) is an underdiagnosed digestive disorder that causes severe nutritional and respiratory complications. Our aim was to determine the accuracy of the Eating ...Assessment Tool (EAT‐10) and the Volume‐Viscosity Swallow Test (V‐VST) for clinical evaluation of OD.
Methods
We studied 120 patients with swallowing difficulties and 14 healthy subjects. OD was evaluated by the 10‐item screening questionnaire EAT‐10 and the bedside method V‐VST, videofluoroscopy (VFS) being the reference standard. The V‐VST is an effort test that uses boluses of different volumes and viscosities to identify clinical signs of impaired efficacy (impaired labial seal, piecemeal deglutition, and residue) and impaired safety of swallow (cough, voice changes, and oxygen desaturation ≥3%). Discriminating ability was assessed by the AUC of the ROC curve and sensitivity and specificity values.
Key Results
According to VFS, prevalence of OD was 87%, 75.6% with impaired efficacy and 80.9% with impaired safety of swallow including 17.6% aspirations. The EAT‐10 showed a ROC AUC of 0.89 for OD with an optimal cut‐off at 2 (0.89 sensitivity and 0.82 specificity). The V‐VST showed 0.94 sensitivity and 0.88 specificity for OD, 0.79 sensitivity and 0.75 specificity for impaired efficacy, 0.87 sensitivity and 0.81 specificity for impaired safety, and 0.91 sensitivity and 0.28 specificity for aspirations.
Conclusions & Inferences
Clinical methods for screening (EAT‐10) and assessment (V‐VST) of OD offer excellent psychometric proprieties that allow adequate management of OD. Their universal application among at‐risk populations will improve the identification of patients with OD at risk for malnutrition and aspiration pneumonia.
Despite its high prevalence and severe complications, oropharyngeal dysphagia (OD) is not always systematically explored and detected, and most patients are not even diagnosed and do not receive any treatment for this condition. Videofluoroscopy (VFS) is the gold standard to OD diagnosis, however, it is not feasible to perform a VFS on every patient at risk for OD. The screening method Eating Assessment Tool (EAT‐10) and the clinical bedside method, Volume‐Viscosity Swallow Test (V‐VST) offer high accuracy for detecting OD.
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DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
Microbial corrosion limits the use of metallic structures in a variety of technological processes and applications. Here, we report the first demonstration of graphene as a passive layer that retards ...microbially-induced galvanic corrosion (MIC) of metals for extended periods of time (∼2700h). The effectiveness of the MIC-resistant graphene coating was evaluated under realistic operating conditions by testing baseline Ni foams and graphene-coated Ni foams as anodes in a microbial fuel cell. The rates of Ni dissolution in the graphene-coated Ni anode were at least an order of magnitude lower than the baseline (uncoated) Ni electrode. Electrochemical impedance spectroscopy characterization revealed that the MIC of Ni was impeded by over 40-fold when coated with graphene.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
We theoretically demonstrate a viable approach to spin squeezing in optical lattice clocks via optical dressing of one clock state to a highly excited Rydberg state, generating switchable atomic ...interactions. For realistic experimental parameters, these interactions are shown to generate over 10 dB of squeezing in large ensembles within a few microseconds and without degrading the subsequent clock interrogation.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
Summary
Malaria, being an epidemic disease, demands its rapid and accurate diagnosis for proper intervention. Microscopic image‐based characterization of erythrocytes plays an integral role in ...screening of malaria parasites. In practice, microscopic evaluation of blood smear image is the gold standard for malaria diagnosis; where the pathologist visually examines the stained slide under the light microscope. This visual inspection is subjective, error‐prone and time consuming. In order to address such issues, computational microscopic imaging methods have been given importance in recent times in the field of digital pathology. Recently, such quantitative microscopic techniques have rapidly evolved for abnormal erythrocyte detection, segmentation and semi/fully automated classification by minimizing such diagnostic errors for computerized malaria detection. The aim of this paper is to present a review on enhancement, segmentation, microscopic feature extraction and computer‐aided classification for malaria parasite detection.
Lay description
Malaria is one of the parasitic infections, which transmits from one infected patient to healthy person through the bite of an Anopheles mosquito. Plasmodium species are responsible for malaria infection. Being an epidemic disease, malaria demands its rapid and accurate diagnosis for proper intervention. The most common and frequently followed diagnostic procedure is the visual assessment of microscopic images of peripheral blood smears and this is adopted as the gold standard for malaria characterization. This kind of manual analysis introduces inter‐observer variability leading to miss diagnosis. As a result delayed diagnosis happens. Apart from the limitations in conventional diagnosis process, it is very hard to get clinicians around the clock in rural areas. Scientists have shown an alternate way of diagnosis through computational evaluation of microscopic images which can help the medical community to overcome the aforesaid restrictions of conventional method. The technological advancement can also aid the tele‐diagnosis. Hence, the implementations and development of advanced computer vision techniques for microscopic image computing has become a popular field of research in digital pathology in recent times. Besides this research issue deals with real life problem and the outcome of this research has direct impact on mankind, which encourages researchers to get engaged in a pursuit. From the viewpoint of machine learning and pattern classification, automatically identifying the different malaria parasite infections and their sub‐types from light microscopic blood smear images is the challenging and essential task. The noisy interference, typical shape of infected erythrocytes (different types and sub‐types) and limited imaging characteristics make the computational analysis very challenging. Researchers have followed various computer vision approaches to deal with the difficulties and finally have come up with desired outcomes through minimizing diagnostic errors.
In this paper, authors represent a systematic chronological review of existing techniques of malarial characterization from microscopic images through addressing different stages of image processing methodology viz. pre‐processing (reducing staining variation, noise reduction etc.), segmentation (erythrocytes and chromatin detection), features extraction, potential feature set selection and pattern classification (characterization of malaria) and also comparing the performance of algorithms as per the information reported in literature. This review paper will certainly help new researchers to get a complete overview on microscopic image analysis for malaria screening and also assist them to find the gaps in existing literature, so that they can find some suitable approach for further modification to develop robust technique.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
In this model we discuss the bioeconomic harvesting of a prey–predator fishery in which both the species are infected by some toxicants released by some other species. Here both the species are ...harvested where we use the usual
catch-per-unit-effort hypothesis. The dynamical behaviour of the exploited system is examined. The possibility of existence of a bionomic equilibrium is considered. The optimal harvesting policy is studied by using Pontryagin’s maximal principle. Some numerical examples and the corresponding solution curves are studied to illustrate the results of the model. Finally, the existence of limit cycle is discussed.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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