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Albert Einstein, in an Address in Chicago observed: [t]he existence and validity of human rights are not written in the stars. The ideals concerning the conduct of men towards each other and the desirable structure of the community have been conceived and taught by enlightened individuals in the course of history. Those ideals and convictions which resulted from historical experience, from the craving for beauty and harmony, have been readily accepted in theory by man – and at all times, have been trampled upon by the same people under the pressure of their animal instincts. A large part of history is therefore replete with the struggle for those human rights, an eternal struggle in which a final victory can never be won. But to tire in that struggle would mean the ruin of society.
Otitis externa is the inflammation of the external auditory canal. The disease is common and shows a seasonal variation with a greater incidence in warmer months. Pseudomonas aeruginosa is a common pathogen in otitis externa and in this retrospective study, we show a corresponding seasonal variation in the proportional incidence of P. aeruginosa isolates from otitis externa in South East England. In total 7770 patients were diagnosed with otitis externa over a period of 9 years from January 2008 to December 2016. P. aeruginosa was isolated from 2802 patients (proportional incidence of 36%). Incidence was higher in the months of August, September and October and in patients between 5 and 15 years of age. We postulate a combination of increased contact with water during warm weather in the holiday season and increased rainfall in the preceding season as a putative mechanism for the seasonal trends.
We study the motion of a buoyant or a nearly neutrally buoyant nano-sized spheroid in a fluid filled tube without or with an imposed pressure gradient (weak Poiseuille flow). The fluctuating hydrodynamics approach and the deterministic method are both employed. We ensure that the fluctuation–dissipation relation and the principle of thermal equipartition of energy are both satisfied. The major focus is on the effect of the confining boundary. Results for the velocity and the angular velocity autocorrelations (VACF and AVACF), the diffusivities and the drag and the lift forces as functions of the shape, the aspect ratio, the inclination angle and the proximity to the wall are presented. For the parameters considered, the boundary modifies the VACF and AVACF such that three distinct regimes are discernible – an initial exponential decay followed by an algebraic decay culminating in a second exponential decay. The first is due to the thermal noise, the algebraic regime is due both to the thermal noise and the hydrodynamic correlations, while the second exponential decay shows the effect of momentum reflection from the confining wall. Our predictions display excellent comparison with published results for the algebraic regime (the only regime for which earlier results exist). We also discuss the role of the off-diagonal elements of the mobility and the diffusivity tensors that enable the quantifications of the degree of lift and margination of the nanocarrier. Our study covers a range of parameters that are of wide applicability in nanotechnology, microrheology and in targeted drug delivery.
Several attempts were made to detect the possible radio recombination lines of positronium near the galactic center. An absorption feature seen at λ6cm, in the D-configuration of the VLA was not confirmed by subsequent observations at λ6cm and λ20cm using the B and C configurations of the VLA. An observation at λ3mm using the IRAM 30m telescope also did not detect any line. On the basis of one recombination line photon for every positron (McClintock 1984), our non-detections imply an upper limit to the positron production rate of < 3.1 × 1043 s−1, within about 2″ of the galactic center.
The Fontan connection, originally described in 1971, is used to provide palliation for patients with many forms of CHDs that cannot support a biventricular circulation. An increasing number of females who have undergone these connections in childhood are now surviving into adulthood and some are becoming pregnant. We report a case of a 29-year-old woman who presented with a twin pregnancy at 33 weeks of gestation. She had significant deterioration of her cardiovascular status before the twin babies were delivered by emergency caesarean section owing to associated obstetric complications. This report also highlights the various maternal and fetal complications occurring in pregnancy of Fontan-palliated patients and suggests the need for meticulous pre-conception counselling and strict perinatal care.
It has become more evident during the last three years that the study of interstellar matter is paramount to understand the evolution of the universe and its constituents. From observations of the present state of the interstellar medium, in our galaxy, in other galaxies, and between galaxies, it is possible to test theories of: evolution of the universe, formation and evolution of galaxies, formation and evolution of stars and of the evolution of the interstellar medium itself. The amount of information on the interstellar medium that has been gathered during the 1982-1984 period has been very large and the theoretical models that have been ellaborated to explain these observations have been very numerous, these facts show that the subject of our Commission constitutes a very active field of astronomical research.
In this study, we present the case of a neonate with obstructed infracardiac total anomalous pulmonary venous connection with severe pulmonary hypertension and a patent ductus arteriosus with right-to-left shunting. The patient had an unusual finding of pandiastolic flow reversal in the upper descending thoracic aorta. He underwent emergency surgical re-routing of the pulmonary veins to the left atrium, and postoperative echocardiography showed disappearance of the descending aortic flow reversal. We hypothesise that in severely obstructed total anomalous pulmonary venous connection the left ventricular output may be extremely low, resulting in flow reversal in the descending aorta.
Triggering of the spark discharges in the Ruderman and Sutherland model by background gamma rays is shown to be effective only within a narrow range of neutron star magnetic fields centred on 2.5 × 1012 gauss. This calculated range of field strengths is in good agreement with ‘observed’ values, suggesting that (a) such triggering is operative, and (b) that neutron stars with much stronger fields do not function as pulsars.
An optimization technique is coupled with crystal plasticity based finite element (CPFE) computations to aid the microstructural design of a wrought magnesium alloy for improved strength and ductility. The initial microstructure consists of a collection of sub-micron sized grains containing deformation twins. The variables used in the simulations are crystallographic texture, and twin spacing within the grains. It is assumed that plastic deformation occurs mainly by dislocation slip on two sets of slip systems classified as hard and soft modes. The hard modes are those slip systems that are inclined to the twin planes and the soft mode consists of dislocation glide along the twin plane. The CPFE code calculates the stress-strain response of the microstructure as a function of the microstructural parameters and the length-scale of the features. A failure criterion based on a critical shear strain and a critical hydrostatic stress is used to define ductility. The optimization is based on the sequential generation of an initial population defined by the texture and twin spacing variables. The CPFE code and the optimizer are coupled in parallel so that new generations are created and analyzed dynamically. In each successive generation, microstructures that satisfy at least 90% of the mean strength and mean ductility in the current generation are retained. Multiple generation runs based on the above procedure are carried out in order to obtain maximum strength-ductility combinations. The implications of the computations for the design of a wrought magnesium alloy are discussed. Research sponsored by the Laboratory Directed Research and Development Program of Oak Ridge National Laboratory, managed by UT-Battelle, LLC, for the U. S. Department of Energy.
The pelagic thresher shark Alopias pelagicus is a large, wide-ranging Indo-Pacific Ocean pelagic shark. In this paper, the first record of the pelagic thresher shark, caught from the Lakshadweep Sea is reported. The shark 275 cm in total length was caught by drift longline operation at depth of 60 m in the Lakshadweep Sea (10°52N latitude 72°13E longitude).
This study was carried out to define the anatomical criteria for the diagnosis of inferior-type caval vein defect and compare the echocardiographic findings with surgical findings.
The records of 19 patients – 13 male and six female patients in the age group of 18 months to 27 years, who were diagnosed as inferior-type caval vein defect with or without anomalous drainage of right pulmonary vein(s) on echocardiography – were retrospectively reviewed and compared with surgical findings.
Surgical diagnosis of inferior-type caval vein defect was confirmed in 17 of the 19 patients. In two patients, the surgical diagnosis was that of a large fossa ovalis atrial septal defect – confluent defect and fossa ovalis atrial septal defect with deficient inferior rim in one patient each. Surgical diagnosis of anomalous drainage of pulmonary vein(s) was based on the course of the superior rim of the defect in relation to the pulmonary veins. Our echocardiographic impression of the pulmonary veins appearing in its normal position but showing abnormal drainage to right atrium was in agreement with the surgical notes. Discrepancy was found in the number of pulmonary veins draining anomalously. The discordance was related to overdiagnosis of anomalous drainage in all except one, that is, three out of four. In one, only the right lower pulmonary vein was diagnosed to be anomalous, whereas both right upper and lower pulmonary veins were found to be anomalous.
Echocardiography provides definite diagnosis of inferior-type caval vein defect. Inferior caval vein straddling and an intact fossa ovalis are prerequisites for diagnosis. Anomalous pulmonary venous drainage of the right pulmonary veins is very common in our series, although accurate diagnosis of the number of pulmonary veins was not possible in all cases. Multiple views on transthoracic echocardiography starting from the subxiphoid views delineate the morphology accurately. Transoesophageal echocardiography is required only in patients in whom the windows, especially the subxiphoid, are not adequate.
The overarching goal of Dye Sensitized Solar Cells (DSSCs) is to improve photovoltaic performance and their long-term stability for use in practical applications because of their simple fabrication technology at a reasonable cost. The focus of this paper is to achieve cell stability and also to improve solar energy conversion efficiency experimenting with different electrolytes. The electrolyte’s role is critical to sustain the DSS cell performance over time to instill cell stability. Four different electrolytes, Iodolyte R-150, AN-50, PN-50 and MPN-100, are experimented in this work for fabricating the dye-sensitized solar cells for studying both the stability and efficiency of the DSSCs.
The electrolyte selection was made using the following key electrolyte parameters; lower viscosity for easier injection into the cell, lower vapor pressure and higher boiling point to minimize electrolyte evaporation, wide redox window to generate sufficient donating electrons to the dye, lower cost and non-toxicity. Electrolytes with higher concentration of Iodolyte were chosen for this study to widen redox potential window. These are Iodide based redox electrolytes and are made with 100 mM of tri-iodide in 3-methoxypropionitrile. The results of this investigation revealed that the cell with Iodolyte R-150 electrolyte achieved improved performance having an efficiency of 10.2% when compared to the reference cell efficiency of 8.4% with Iodolyte R-50. These cells were stabilized over a time of 4 weeks. The fill factor of the cell changed about 10% and the internal resistance decreased from 6.7 to 4.3 Ω. The results of this experiment demonstrated reduced internal resistance, and improved fill factor contributed to higher cell efficiency and stability. The results of the work presented in this paper support the argument that electrolytes with higher Iodolyte concentration can enhance the cell efficiency and stability along with scaling down of the cell size.
The Dye-sensitized Solar Cell (DSSC) has been regarded as the next-generation solar cell because of its simple and low cost fabrication process. The experiments for optimizing the cell efficiency were carried out in this work include varying the TiO2 layer thickness on the working electrode and determining the most favorable nanoparticle size in the TiO2 paste. The TiO2 electrode or working electrode was fabricated using screen printing technique with the Coatema tool with thicknesses ranging from ~20 to 66 μm. It was observed that both open circuit voltage and short circuit current were found to have measurable dependence on the TiO2 layer thickness. The open circuit voltage changed from 0.77 to 0.82 V and correspondingly the short circuit current also varied from ~19 to 23 mA/cm2 depending on the TiO2 layer thickness. Additionally, the cell with 40 μm TiO2 thickness showed 9.06% photo conversion efficiency compared to 6.4% and 8.5% efficiency obtained for the cells with 20 μm and 66 μm TiO2 thicknesses respectively. The second part of the experiment was conducted using three different nanoparticle sizes of 13 nm, 20 nm and 37nm in the TiO2 layer to identify optimum nanoparticle size by maintaining the TiO2 film thickness at 40 μm. The cell with 20 nm size nanoparticle, in combination with 40 μm TiO2 thickness showed 11.2% efficiency that is in par or slightly better than the efficiency value reported for the DSSC in the literature as of now. The work described in this paper showed best possible values for the TiO2 layer thickness and nanoparticle size in the TiO2 for obtaining improved cell efficiency of 11.2%.
We have carried out experiments on dual-damascene Cu interconnects with different lengths. We find that at short lengths, similar to Al-based interconnects, the reliability of Cubased interconnects improves. Also like Al interconnects, some short Cu segments do not form voids that cause failure before back-stresses prevent the further growth of voids. However, unlike Al-based interconnects, there is no apparent deterministic current-density line-length product (jL) for which all lines are immortal. This is related to the absence of a conducting refractory-metal overlayer in Cu-technology that can shunt current around small voids. Also unlike Al, we find that at long lengths a sub-population of Cu lines is immortal. We propose that this is the result of rupture of the thin refractory metal liner at the base of the dual-damascene Cu vias. As a consequence of this complex behavior, median times to failure and lifetime variations are minimum at intermediate line lengths.
Conducting polyaniline/barium titanate (PANI/BaTiO3) composites exhibiting piezoresistivity properties have been synthesized by the in situ deposition technique by placing a fine grade powder of BaTiO3 in the polymerization reaction mixture. The polyaniline was formed preferentially on the ceramic particles giving a much higher yield for PANI than in absence of the BaTiO3 These composites exhibited piezoresistivity with the piezosensitivity being maximum at a certain composition. The current–voltage characteristics clearly revealed a nonlinear space charge controlled charge transport process. A large hysteresis in these characteristics was also observed which was dependent on the BaTiO3 content in a composite. The various results have been explained on the basis of the charge transport mechanism in the heterogeneous conducting material having insulating domains dispersed in it.
Our aim was to assess the immediate and short term results of closure of moderate and large patent arterial ducts using the self-expanding and repositionable Amplatzer device.
We attempted closure in 25 patients (10 Females and 15 males) using the Amplatzer occluder. Their median age was 48 months with a range from 8months to 26years and median weight of 14kg with a range from 4.5kg to 48kg. The mean ductal diameter was 4 (S.D 1.51mm). A 6F/7F long sheath was used to deliver the device. Follow up was performed with colour- flow mapping of the pulmonary trunk within 24 hours, at 3 months, and 6 months of closure.
Of the 25 patients, the device was placed successfully in 23. Concurrent angiography showed immediate closure in 12 patients, while 8 had trivial shunting and 3 had mild shunting. Within 24 hours, Doppler examination revealed complete closure in all but three patients, who had a mild residual shunt. Two attempts were unsuccessful. Both these patients underwent successful surgical ligation. All except one patient were discharged on the next day. Of the 23 patients, 15 (65%) have been followed up for 3months, while 8 (35%) have completed 6 months of follow-up. Of the three patients initially with mild residual flow, two had completely closed at 3 months The one remaining patient is yet to be seen at the 3 month follow-up. Thus, at 3 months, all patients studies had shown complete closure.
Antegrade transcatheter closure using the Amplatzer duct occluder is an efficacious treatment for bigger patent arterial ducts. Long-term follow-up is necessary to show sustained benefits and confirm the absence of side effects.
Amongst all primary cardiac tumors, myxomas are the commonest, and their commonest site of origin is the left atrium. Myxomas originating in the left ventricle are rare. When seen, they usually present with a history of systemic embolisation and/or syncopal episodes, with constitutional symptoms being absent. We report here a child with left ventricular myxoma who presented with a prolonged febrile illness.
X-ray powder diffraction data of CoSi are reported. The sample was prepared by an arc melting process and has a cubic structure (space group P213, space group No. 198) with lattice parameter a=4.4427 Å, Dx=6.591 gcm−3, Z=4, and I/Ic=1.03.
We describe post azygos obstruction of the superior caval vein following repair of a mixed variety of totally anomalous pulmonary venous connection. Balloon dilation was immediately successful, and has provided persistent relief at a follow-up of 20 months.