The magnetic field effect on the transport and efficiency of group III tris(8-hydroxyquinoline) organic light emitting diodes

Copyright 2008 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. This article appeared in Journal of Applied Physics 103, 103715 (2008) and may be found at

Shock Geometry and Spectral Breaks in Large SEP Events

Solar energetic particle (SEP) events are traditionally classified as "impulsive" or "gradual." It is now widely accepted that in gradual SEP events, particles are accelerated at coronal mass ejection-driven (CME-driven) shocks. In many of these large SEP events, particle spectra exhibit double power law or exponential rollover features, with the break energy or rollover energy ordered as (Q/A)^α, with Q being the ion charge in e and A the ion mass in units of proton mass m_p . This Q/A dependence of the spectral breaks provides an opportunity to study the underlying acceleration mechanism. In this paper, we examine how the Q/A dependence may depend on shock geometry. Using the nonlinear guiding center theory, we show that α ~ 1/5 for a quasi-perpendicular shock. Such a weak Q/A dependence is in contrast to the quasi-parallel shock case where α can reach 2. This difference in α reflects the difference of the underlying parallel and perpendicular diffusion coefficients κ_(||) and κ ⊥. We also examine the Q/A dependence of the break energy for the most general oblique shock case. Our analysis offers a possible way to remotely examine the geometry of a CME-driven shock when it is close to the Sun, where the acceleration of particle to high energies occurs

Novel Sampling Algorithm for Human Mobility-Based Mobile Phone Sensing

Smart phones or mobile phones enabled with global positioning system (GPS), different types of sensors, and communication technologies have become ubiquitous application development platform for Internet of Things (IoT) and new sensing technologies. Improving sensing area coverage, reducing overlap of sensing area, and energy consumption are important issues under mobile phone sensing. This paper presents human mobility-based mobile phone sensors sampling algorithm. Human mobility patterns and geographical constraints have an impact on performance of mobile phone sensing applications. The real-outdoor location traces of volunteers, collected using GPS-enabled mobile phones are used for performance analysis of proposed work. The proposed mobile phone sensor sampling algorithm considers velocity of human mobility as an important parameter for improving sensing area coverage and reduction of energy consumption. To an extent overlap between sensing area coverage is allowed to overcome, the reduction of sensor data samples caused by spatial regularities of human mobility. The performance is analyzed and evaluated by considering general regular sampling and proposed sampling method for mobile phone sensing activity. The results show that for normal human walking velocity (<;1.5 m/s) proposed mobile phone sensor sampling algorithm performs better in terms of sensing area coverage and reduction of battery energy consumption for mobile phone sensing activity

Levy walk based multi-hop data forwarding protocol for opportunistic mobile phone sensor networks

Unstable link connectivity due to dynamic mobility nature of mobile phone users and error prone wireless link quality increases end-to-end delay for mobile phone based opportunistic network applications. This problem becomes more worse in the presence of large amount of data transmission, like multimedia data. This paper refers to Levy walk based multi-hop data forwarding protocol called Data Transmission Time and Human Walk Velocity (DTT-HWV) for Opportunistic Mobile Phone Sensor Networks (OMPSN). This paper, in particular evaluates the performance of proposed protocol in terms of end-to-end waiting time to receive data, which is an important QoS requirement for data transmission in opportunistic networks. The proposed protocol DTT-HWV reduces end-to-end waiting time to receive data compared to Random Progress (RP) data forwarding method in presence of low battery power and high path loss. Obtained results are helpful in designing and building of large scale data retrieval services for opportunistic networks involving humans in the communication network loop

An evaluation of the technique of use of metered dose inhaler administration in bronchial asthma children

Background: Inadequate understanding and performance of drug administration using metered-dose inhaler (MDI) in paediatric population affects therapeutic outcome. Hence, this study aimed to evaluate the impact of two educational interventional methods for usage of MDI in paediatric patients of bronchial asthma.Methods: This prospective, interventional study was done in paediatric asthma patients who were prescribed drugs with (MDI) with/without spacer at outpatient department of pediatrics. Patients were divided in group A (video) or group B (leaflet) as per random table method and method to use MDI was assessed by using checklist as per WHO guide to good prescribing at baseline. Investigator taught the technique by a video (group A) and leaflet (group B) to the selected population. Patients were followed up after 15 days and assessed for use of MDI using the same checklist. Data were analysed by using paired and unpaired ‘t’-test.Results: A total of 100 pediatric asthma patients were included in study group A (50) and group B (50). The average no. of steps (WHO checklist) followed was significantly improved at post intervention in both group A (with spacer, p<0.0001) as well as B (without spacer, p<0.05). Although average no. of steps followed were more in group A, no significant difference was found between two groups after intervention.Conclusions: As video is an audio-visual method of demonstration, and hence help us memorise the step of inhalational technique in pediatric patients. Repeated demonstration/education to patients/caregivers may improve the method of MDI usage

An intensive monitoring of adverse drug reactions in pediatric hospitalized patients of a tertiary care hospital

Background: Children are at a higher risk of therapeutic failure due to major difference in pharmacokinetic, pharmacodynamics of drugs, off-label use and divergence of their illness from adult. The safety of drugs used in adult patients cannot be extrapolated to a pediatric age group. Hence, this study aimed to evaluate the incidence and overall pattern of adverse drug reactions in pediatric patients hospitalized in pediatric wards at a tertiary care hospital in India.Methods: Pediatric patients up to 12 years hospitalized in two randomly selected pediatric units were enrolled and followed up daily till discharge. Detailed information of patients and ADRs (adverse drug reactions) if any were recorded from case records. ADRs were assessed for incidence, onset, duration, management, outcome, causality, severity, preventability, seriousness and risk factors. Appropriateness of drug treatment in patients with ADRs was analyzed using Phadke’s criteria. Data was analyzed using student’s t test, ANOVA and Chi square test.Results: A total of 700 patients were enrolled (mean age 3.95±0.12 years). A total of 66 ADRs observed in 58 patients. Intravenous (70.4%) being most common route for ADRs. The incidence of ADRs was 8.28%. Majority of ADRs occurred within 1 day, commonly affected skin and appendages followed by (28.78%), GI (25.75%) ADRs were frequently associated with antimicrobials (69.38%) and vaccines and sera (12.24%). Majority of reactions were mild (56%%), non-serious (77.2%), not preventable (95.4%), recovered completely at discharge (83.33%) and had possible (77.2%) causal association with suspect drug. Age group 0-3 years and prescription of ≥5 drugs were risk factors for occurrence of ADRs. Semi rational drug therapy was observed in 65.5% patients.Conclusions: Clinicians should be vigilant regarding occurrence of ADRs in pediatrics especially during the first week of hospitalization. Risk factors like 0-3 years of age and multiple drugs should be taken into consideration during treatment of these patients to help minimize adverse drug reactions

Non-equilibrium condensation and coarsening of field-driven dipolar colloids

In colloidal suspensions, self-organization processes can be easily fueled by external fields. One particularly interesting class of phenomena occurs in monolayers of dipolar particles that are driven by rotating external fields. Here we report results from a computer simulation study of such systems focusing on the clustering behavior also observed in recent experiments. The key result of this paper is a novel interpretation of this pattern formation phenomenon: We show the clustering to be a by-product of a vapor-liquid first order phase transition. In fact, the observed dynamic coarsening process corresponds to the spindodal demixing that occurs during such a transitionComment: 6 pages, 5 figure

Production of a Higgs pseudoscalar plus two jets in hadronic collisions

We consider the production of a Higgs pseudoscalar accompanied by two jets in hadronic collisions. We work in the limit that the top quark is much heavier than the Higgs pseudoscalar and use an effective Lagrangian for the interactions of gluons with the pseudoscalar. We compute the amplitudes involving: 1) four gluons and the pseudoscalar, 2) two quarks, two gluons and the pseudoscalar and 3) four quarks and the pseudoscalar. We find that the pseudoscalar amplitudes are nearly identical to those for the scalar case, the only differences being the overall size and the relative signs between terms. We present numerical cross sections for proton-proton collisions with center-of-mass energy 14 TeV.Comment: 12 pages, LaTeX, 4 Postscript figures, submitted to Phys. Rev.

Supernova Host Galaxies in the Dark Energy Survey: I. Deep Coadds, Photometry, and Stellar Masses

The five-year Dark Energy Survey supernova programme (DES-SN) is one of the largest and deepest transient surveys to date in terms of volume and number of supernovae. Identifying and characterising the host galaxies of transients plays a key role in their classification, the study of their formation mechanisms, and the cosmological analyses. To derive accurate host galaxy properties, we create depth-optimised coadds using single-epoch DES-SN images that are selected based on sky and atmospheric conditions. For each of the five DES-SN seasons, a separate coadd is made from the other 4 seasons such that each SN has a corresponding deep coadd with no contaminating SN emission. The coadds reach limiting magnitudes of order ∼ 27 in g-band, and have a much smaller magnitude uncertainty than the previous DESSN host templates, particularly for faint objects. We present the resulting multi-band photometry of host galaxies for samples of spectroscopically confirmed type Ia (SNe Ia), core-collapse (CCSNe), and superluminous (SLSNe) as well as rapidly evolving transients (RETs) discovered by DES-SN. We derive host galaxy stellar masses and probabilistically compare stellar-mass distributions to samples from other surveys. We find that the DES spectroscopically confirmed sample of SNe Ia selects preferentially fewer high mass hosts at high redshift compared to other surveys, while at low redshift the distributions are consistent. DES CCSNe and SLSNe hosts are similar to other samples, while RET hosts are unlike the hosts of any other transients, although these differences have not been disentangled from selection effects

Synthesis and Elastic Characterization of Zinc Oxide Nanowires

Zinc oxide nanowires, nanobelts, and nanoneedles were synthesized using the vapor-liquid-solid technique. Young's modulus of the nanowires was measured by performing cantilever bending experiments on individual nanowires in situ inside a scanning electron microscope. The nanowires tested had diameters in the range of 200–750 nm. The average Young's modulus, measured to be 40 GPa, is about 30% of that reported at the bulk scale. The experimental results are discussed in light of the pronounced electromechanical coupling due to the piezoelectric nature of the material