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The early phase of the coronavirus disease 2019 (COVID-19) pandemic and ongoing efforts for mitigation underscore the importance of universal travel and symptom screening. We analyzed adherence to documentation of travel and symptom screening through a travel navigator tool with clinical decision support to identify patients at risk for Middle East Respiratory Syndrome.
An analytical study of the small amplitude electron acoustic double layers in a magnetized plasma consisting of superthermal electrons and ions along with cold fluid electrons is discussed. The dispersion relation allows electron acoustic waves with the frequency within electron and ion gyro-frequency in the modelled plasma. In the process of study of the nonlinear structures, the Sagdeev pseudo-potential method for small amplitude regions is employed. The existence domains for the double layers are investigated in terms of the Mach numbers of the structures and the temperature ratios of the species for different ratios of their concentration. The effects of the compositional parameters on the nature and size of the double layers are also explored and it is observed that the plasma can support both compressive and rarefactive double layers depending on the values of those parameters and the Mach numbers.
Spiking Neural Networks propose to mimic nature’s way of recognizing patterns and making decisions in a fuzzy manner. To develop such networks in hardware, a highly manufacturable technology is required. We have proposed a silicon-based leaky integrate and fire (LIF) neuron, on a sufficiently matured 32 nm CMOS silicon-on-insulator (SOI) technology. The floating body effect of the partially depleted (PD) SOI transistor is used to store “holes” generated by impact ionization in the floating body, which performs the “integrate” function. Recombination or equivalent hole loss mimics the “leak” functions. The “hole” storage reduces the source barrier to increase the transistor current. Upon reaching a threshold current level, an external circuit records a “firing” event and resets the SOI MOSFET by draining all the stored holes. In terms of application, the neuron is able to show classification problems with reasonable accuracy. We looked at the effect of scaling experimentally. Channel length scaling reduces voltage for impact ionization and enables sharper impact ionization producing significant designability of the neuron. A circuit equivalence is also demonstrated to understand the dynamics qualitatively. Three distinct regimes are observed during integration based on different hole leakage mechanism.
A total of 45 strains of Vibrio cholerae O1 isolated from 10 different places in India where they were associated with cases of cholera between the years 2007 and 2008 were examined by molecular methods. With the help of phenotypic and genotypic tests the strains were confirmed to be O1 El Tor biotype strains with classical ctxB gene. Polymerase chain reaction (PCR) analysis by double – mismatch amplification mutation assay PCR showed 16 of these strains carried the ctxB-7 allele reported in Haitian strains. Sequencing of the ctxB gene in all the 45 strains revealed that in 16 strains the histidine at the 20th amino acid position had been replaced by asparagine and this single nucleotide polymorphism did not affect cholera toxin production as revealed by beads enzyme-linked immunosorbent assay. This study shows that the new ctxB gene sequence was circulating in different places in India. Seven representatives of these 45 strains analysed by pulsed – field gel electrophoresis showed four distinct Not I digested profiles showing that multiple clones were causing cholera in 2007 and 2008.
There is a genetic contribution to the risk of suicide, but sparse prior research on the genetics of suicidal ideation.
Active and passive suicidal ideation were assessed in a Sri Lankan population-based twin registry (n = 3906 twins) and a matched non-twin sample (n = 2016). Logistic regression models were used to examine associations with socio-demographic factors, environmental exposures and psychiatric symptoms. The heritability of suicidal ideation was assessed using structural equation modelling.
The lifetime prevalence of any suicidal ideation was 13.0% (11.7–14.3%) for men; 21.8% (20.3–23.2%) for women, with no significant difference between twins and non-twins. Factors that predicted suicidal ideation included female gender, termination of marital relationship, low education level, urban residence, losing a parent whilst young, low standard of living and stressful life events in the preceding 12 months. Suicidal ideation was strongly associated with depression, but also with abnormal fatigue and alcohol and tobacco use. The best fitting structural equation model indicated a substantial contribution from genetic factors (57%; CI 47–66) and from non-shared environmental factors (43%; CI 34–53) in both men and women. In women this genetic component was largely mediated through depression, but in men there was a significant heritable component to suicidal ideation that was independent of depression.
These are the first results to show a genetic contribution to suicidal ideation that is independent of depression outside of a high-income country. These phenomena may be generalizable, because previous research highlights similarities between the aetiology of mental disorders in Sri Lanka and higher-income countries.
Spectrum tuning in phosphor converted white light emitting diodes (pc-WLED) is done by mixing powders of phosphor compounds (with different emission wavelengths) in different weight ratios. In this paper, a new methodology for designing unique full spectrum phosphor mixtures (with fixed weight ratios of different emission phosphor) has been presented that could provide a wide range of pc-WLED spectrum. This is done by optimizing the excitation and emission spectra of the phosphor compounds used in the mixture. A unique phosphor mixture comprising of Eu2+ and Ce3+-Na1+ activated compounds of SrGa2S4, CaGa2S4, SrS, CaS and CaF2 was used to produce full spectrum warm, neutral and cool white LEDs with color temperatures between 2500 K and 7500 K and with color rendering index exceeding 95.
We address two aspects of finitely generated modules of finite projective dimension over local rings and their connection in between: embeddability and grade of order ideals of minimal generators of syzygies. We provide a solution of the embeddability problem and prove important reductions and special cases of the order ideal conjecture. In particular, we derive that, in any local ring R of mixed characteristic p > 0, where p is a nonzero divisor, if I is an ideal of finite projective dimension over R and p 𝜖 I or p is a nonzero divisor on R/I, then every minimal generator of I is a nonzero divisor. Hence, if P is a prime ideal of finite projective dimension in a local ring R, then every minimal generator of P is a nonzero divisor in R.
Surfactant-free SnS nanoparticles were synthesized using continuous spray pyrolysis (CoSP) technique and used as sensitizers on electro-deposited ZnO nanowire arrays for fabrication of extremely thin absorbing (ETA) layers. The high-surface-area nanowire layer on ITO substrate was directly over-coated by SnS nanoparticles. The morphology of the ZnO/SnS nanostructures showed the coverage of orthorhombic SnS nanocrystals on hexagonal ZnO prismatic nanowires. The crystalline phase of the ZnO/SnS nanostructures was studied using X-ray diffraction. Conducting AFM showed a nonlinear characteristics confirming the junction formation.
We develop a framework for analysing the outcome of resource competition based on
bifurcation theory. We elaborate our methodology by readdressing the problem of
competition of two species for two resources in a chemostat environment. In the case of
perfect-essential resources it has been extensively discussed using Tilman’s
representation of resource quarter plane plots. Our mathematically rigorous analysis
yields bifurcation diagrams with a striking similarity to Tilman’s method including the
interpretation of the consumption vector and the resource supply vector. However, our
approach is not restricted to a particular class of models but also works with other
trophic interaction formulations. This is illustrated by the analysis of a model
considering interactively-essential or complementary resources instead of
prefect-essential resources. Additionally, our approach can also be used for other
ecosystem compositions: multiple resources–multiple species communities with equilibrium
or oscillatory dynamics. Hence, it gives not only a new interpretation of Tilman’s
graphical approach, but it constitutes an extension of competition analyses to communities
with many species as well as non-equilibrium dynamics.
A temporal relationship of Japanese encephalitis virus (JEV) transmission in pigs, mosquitoes and humans revealed that sentinel pig seroconversions were significantly associated with human cases 4 weeks before (P = 0·04) their occurrence, highly correlated during the same time and 2 weeks before case occurrence (P < 0·001), and remained significantly correlated up to 2 weeks after human case occurrence (P < 0·01). JEV was detected in the same month in pigs and mosquitoes, and peaks of pig seroconversion were preceded by 1–2 months of peaks of infection in vectors. Kaplan–Meier analysis indicated that detection of JEV-positive mosquitoes was significantly associated with the median time to occurrence of seroconversion in pigs (P < 0·05). This study will not only help in predicting JEV activity but also accelerate timely vector control measures and vaccination programmes for pigs and humans to reduce the Japanese encephalitis risk in endemic areas.
We present an extremely rare case of isolated angiokeratoma of the tongue.
Case report and review of related literature.
An 18-year-old, male adolescent presented with a fleshy, intermittently bleeding mass in the posterior third and base of the tongue. The lesion was initially suspected to be a lingual thyroid or haemangioma, but histopathological features were consistent with angiokeratoma. Magnetic resonance imaging revealed that the lesion extended up to the vallecula and involved the lamina propria and superficial tongue musculature. No similar lesions were found elsewhere in the body. No metabolic derangements were identified in the patient or his family. The 2.6 × 1.5 × 0.5 cm mass was excised under general anaesthesia.
We present the 1st case of isolated lingual angiokeratoma in a male, the 4th such case overally, the largest ever documented. The lesion was situated in the posterior third and base of the tongue, a position not previously described.
We study resonant tunneling through a layered medium with a passive negative index medium (NIM) slab as a constituent layer. Using a causal
model for susceptibilities with the parameters of a recently reported metamaterial [G. Dolling, C. Enkrich, M. Wegener, C.M. Soukoulis, S. Linden, Opt. Lett. 31, 1800 (2006)] we show that resonant tunnelling and the associated delay are mostly suppressed. This is in sharp contrast with the naive approach of retaining phase velocity dispersion with arbitrary low losses, predicting sharp resonances with large associated delays. This is shown to be a nontrivial issue because of the necessity of losses for NIM behaviour, while their presence spoils the quality factor of the resonant devices.
Information and communication technologies, especially in the forms of mobile telecommunications, satellite imaging, and geographical information systems, promise to significantly improve the practice of humanitarian relief. A working group convened at the Humanitarian Action Summit 2009, has begun investigating the challenges to implementing these technologies in field operations, keeping in mind the ethical considerations of linking people to place, and pledging to build a community of practice among academics, practitioners, and developers.
The end of the cold war and the rise of international terrorism have dramatically changed perceptions of national security. Where nations once saw threats emanating primarily from state actors located abroad, they now look also at nonstate entities acting both at home and abroad, as well as to failed states. Threats from nonstate actors have become a more significant issue for both rich and poor states. Table 2.1 displays those changes in perception of the threat, using the United States as an example.
A full analysis of the costs of terrorism would include the costs to rich and poor states, including those costs of rich country efforts to defend against terrorist threats imposed on the poor. This chapter takes a first step by examining the costs to the rich states of addressing the terrorism threat, not the costs of terrorism itself or of the immediate responses to an attack. In that sense, the costs might be thought of as the “secondary” cost of countering terrorism, rather than the “proximate” costs of terrorism. Understandably, the latter have received more attention than the former. However, some sense of where the money is going is necessary to identify possible trade-offs and ask whether the current portfolio of expenditures is the most sensible one. Table 2.2 summarizes the various distinctions and their implications for cost.
The multilayers of ferroelectric (FE) Pb(Zr, Ti)O3 (PZT) and ferromagnetic (FM) CoFe2O4 (CFO) thin films with 3, 5, and 9 layers having configurations PZT/CFO (PC) and CFO/PZT (CP) were fabricated by pulsed laser deposition technique. We have investigated the effect of inter-diffusion at the interface of multilayers (MLs) and reversing the order of FE and FM layers in the multilayers configuration on the electrical/magnetic properties. The TEM of the films showed that the layer structure was not maintained and the inter-diffusion of the CFO into PZT and vice verse were observed at the interface of MLs. Both the PC and CP configurations of multilayer films exhibited pseudo FE hysteresis loop and proper FM hysteresis loops at room temperature. Reversing the multilayer configuration from CP to PC resulted in increasing the pseudo remanent polarization, however this behavior was not observed in magnetic properties. The frequency and temperature dependences of the impedance and modulus spectroscopy of the multilayer PC and CP films were studied in the ranges of 102 to 106 Hz and 200 to 650 K respectively. The electrical response of all multilayer films investigated could be resolved into two contributions. We attributed these to the grain and grain boundary effects in impedance and modulus formalism. We found that the difference between the grain and grain boundary capacitive effect decreased due to increase of the number of layers.
Polycrystalline electroceramics have been prepared by varying modifier to former (Bi/La) ratios (
) according to the complex formula
Biz] 0.08[Zr0.65Ti0.35] 0.98O3 (PLBZT), where z = 0.0, 0.3, 0.6.
The electrical properties of PLBZT compounds were studied using the ac
impedance spectroscopy technique over a wide range of temperature
(30–500 °C) in the frequency range of 100 Hz–1 MHz.
Nyquist plots recorded at different temperatures show a decrease in the bulk
resistance (Rb) with rise in temperature for PLZT material (z = 0.0)
i.e., NTCR behavior like semiconductors. The Nyquist plots also indicates
that the bulk resistance of the material has been observed to be
concentration dependent and decreased in two order of magnitude with higher
Bi-addition in PLZT matrix. Bismuth (Bi) substitution at the lanthanum (La)
position not only resulted in lowering of the electrical resistance with its
higher concentration but also has changed the NTCR behavior of PLZT (z = 0.0) to PTCR (positive temperature coefficient of resistance) for PLBZT.
Electrical property studied by complex impedance spectroscopic method also
indicates the evidence of (i) single electrical relaxation attributed to the
presence of bulk contribution to the electrical properties, (ii) presence of
temperature dependent electrical relaxation phenomenon and (i) diminution in
the barrier to the mobility of charge carrier on Bi-substitution.
A total of 113 strains of Shigella dysenteriae type 2 isolated from patients attending the Dhaka diarrhoea treatment centre of ICDDR,B: Centre for Health and Population Research during the period 1999–2004 were studied. Serotype of the isolates was confirmed using commercially available antisera. Except for arabinose fermentation, all the strains had similar biochemical reactions. More than 60% of the strains were sensitive to commonly used antibiotics; only 6% (n=7) of the strains were resistant to nalidixic acid, and none of the strains were resistant to mecillinam and ciprofloxacin. All strains were invasive as demonstrated by the presence of a 140 MDa plasmid, ial, sen and ipaH genes, Congo Red absorption ability and by the Sereny test performed on representative strains. Plasmid patterns were heterogeneous but more than 50% of strains were confined to a single pattern. All strains possessed a 1·6 MDa plasmid and 87% of the strains contained a 4 MDa plasmid. Middle-range plasmids (90 MDa to 30 MDa) present in 36% of the strains were not associated with antibiotic resistance. All the strains were clustered within a single type with four subtypes by pulsed-field gel electrophoresis while ribotyping patterns of all the strains were identical.