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We simulate the flow of two immiscible and incompressible fluids separated by an interface in a homogeneous turbulent shear flow at a shear Reynolds number equal to
. The viscosity and density of the two fluids are equal, and various surface tensions and initial droplet diameters are considered in the present study. We show that the two-phase flow reaches a statistically stationary turbulent state sustained by a non-zero mean turbulent production rate due to the presence of the mean shear. Compared to single-phase flow, we find that the resulting steady-state conditions exhibit reduced Taylor-microscale Reynolds numbers owing to the presence of the dispersed phase, which acts as a sink of turbulent kinetic energy for the carrier fluid. At steady state, the mean power of surface tension is zero and the turbulent production rate is in balance with the turbulent dissipation rate, with their values being larger than in the reference single-phase case. The interface modifies the energy spectrum by introducing energy at small scales, with the difference from the single-phase case reducing as the Weber number increases. This is caused by both the number of droplets in the domain and the total surface area increasing monotonically with the Weber number. This reflects also in the droplet size distribution, which changes with the Weber number, with the peak of the distribution moving to smaller sizes as the Weber number increases. We show that the Hinze estimate for the maximum droplet size, obtained considering break-up in homogeneous isotropic turbulence, provides an excellent estimate notwithstanding the action of significant coalescence and the presence of a mean shear.
denote a random symmetric
matrix whose upper-diagonal entries are independent and identically distributed Bernoulli random variables (which take values
each). It is widely conjectured that
is singular with probability at most
. On the other hand, the best known upper bound on the singularity probability of
, due to Vershynin (2011), is
, for some unspecified small constant
. This improves on a polynomial singularity bound due to Costello, Tao, and Vu (2005), and a bound of Nguyen (2011) showing that the singularity probability decays faster than any polynomial. In this paper, improving on all previous results, we show that the probability of singularity of
is at most
for all sufficiently large
. The proof utilizes and extends a novel combinatorial approach to discrete random matrix theory, which has been recently introduced by the authors together with Luh and Samotij.
This study analysed the recent changes and patterns of information received about contraceptive methods by contraceptive users in India – an important indicator of quality of care in family planning services. Data were taken from the third and fourth rounds of National Family and Health Surveys (NFHS) conducted in India during 2005–06 and 2015–16. The Method Information Index (MII) was used to capture the information received by respondents on three aspects of contraceptive method use: information about the side-effects of the method, what to do if they experienced any complication from using the method and information received about other methods of contraception. A separate analysis of information received by users about the permanency of sterilization was also carried out. Logistic regression models were applied to assess the independent effects of users’ background characteristics and their states and union territories of residence on method information received by them. The value of the MII nearly doubled from about 16% in 2004–05 to 31% in 2015–16, indicating a marked increase in the information received by contraceptive users in India over the period between 2005–06 and 2015–16. In addition, the percentage of sterilized women who received information about the permanency of the method also increased, from 67% to 80%, over the period. While considerable progress has been made in the last decade, there is still plenty of scope for improvement in the information received by contraceptive users to advance a voluntary approach to family planning.
In resource-constrained settings, primary health centers (PHCs) are critical for universal health coverage. Laboratory service is one of its important components. While PHC and its performance are focused, its laboratory service has been neglected in developing countries like India.
To determine the role of different level of PHC laboratory services on the overall PHC performance.
Cross-sectional study based on 42 PHCs of Osmanabad District, Maharashtra, India was performed. The study used levels of laboratory services in PHC as independent parameter and PHC outpatient department (OPD) visits per day (≤ 80 versus > 80) as dependent parameter. The control parameters used in the study were number of medical doctors, availability of laboratory technicians (LTs) and population coverage by PHC. Field visit was done to collect data on levels of laboratory services, but secondary source was used for other parameters. The logistic regression analysis was performed in study.
The study found variation in PHC population coverage (10 788–74 702) and OPD visits per day (40–182) across PHC. Strong positive association was observed between levels of laboratory services and number of OPD visits per day in PHC. PHC offering both malaria and tuberculosis in-house testing had higher odds (4.81) of getting more OPDs (≥ 80 OPD visits per day) as compared to PHC not offering in-house testing facility for malaria and tuberculosis. This association was stronger in PHCs with lower population coverage (0–75 quartile) as compared to PHCs with higher population coverage (75–100 quartile).
Focus on laboratory services is needed to enhance the existing PHCs performance. Skill-up gradation of existing LT could help in improving the contribution of the existing laboratories in PHC functioning.
Our ability to describe crystal structure features is of crucial importance when attempting to understand structure–property relationships in the solid state. In this paper, the authors introduce robocrystallographer, an open-source toolkit for analyzing crystal structures. This package combines new and existing open-source analysis tools to provide structural information, including the local coordination and polyhedral type, polyhedral connectivity, octahedral tilt angles, component-dimensionality, and molecule-within-crystal and fuzzy prototype identification. Using this information, robocrystallographer can generate text-based descriptions of crystal structures that resemble descriptions written by human crystallographers. The authors use robocrystallographer to investigate the dimensionalities of all compounds in the Materials Project database and highlight its potential in machine learning studies.
This paper discusses the issues involved with creating a Tangible Augmented Reality representation of a product so that it can be effectively and validly used to support the product design process. The development of a TAR representation entails building the physical model of the product, a digital model of the product, and developing interactions between the digital and physical representations. Different products have different user interactions, which makes developing TAR representation for products challenging since a new interaction needs to be mimicked. Challenges of developing TAR representations are discussed by investigating TAR representations of four consumer products: a space heater, a MP3 player, an electric can opener, and a seat assist cushion. The goal of TAR representations is to not only communicate the functionality of a product but also to improve the time efficiency of prototyping of physical products. Hence, having a good understanding of the user interactions that need to be developed and planning the representation for construction in the modeling software and AR software is crucial to making the process of developing a TAR representation efficient.
This study examined the pattern of economic disparity in the modern contraceptive prevalence rate (mCPR) among women receiving contraceptives from the public and private health sectors in India, using data from all four rounds of the National Family Health Survey conducted between 1992–93 and 2015–16. The mCPR was measured for currently married women aged 15–49 years. A concentration index was calculated and a pooled binary logistic regression analysis conducted to assess economic disparity (by household wealth quintiles) in modern contraceptive use between the public and private health sectors. The analyses were stratified by rural–urban place of residence. The results indicated that mCPR had increased in India over time. However, in 2015–16 only half of women – 48% (33% from the public sector, 12% from the private sector, 3% from other sources) – were using any modern contraceptive in India. Over time, the economic disparity in modern contraceptive use reduced across both public and private health sectors. However, the extent of the disparity was greater when women obtained the services from the private sector: the value of the concentration index for mCPR was 0.429 when obtained from the private sector and 0.133 when from the public sector in 2015–16. Multivariate analysis confirmed a similar pattern of the economic disparity across public and private sectors. Economic disparity in the mCPR has reduced considerably in India. While the economic disparity in 2015–16 was minimal among those accessing contraceptives from the public sector, it continued to exist among those receiving services from the private sector. While taking appropriate steps to plan and monitor private sector services for family planning, continued and increased engagement of public providers in the family planning programme in India is required to further reduce the economic disparity among those accessing contraceptive services from the private sector.
South-East Asia’s bird trade is of global conservation concern as it has massively depleted wild populations of many species. Parrots (Order Psittaciformes) are especially vulnerable because they are the most heavily traded group of birds globally under the Convention on International Trade in Endangered Species (CITES) appendices. Singapore’s involvement in the global pet bird trade as a transhipment hub is well documented, particularly for parrots. Yet, much less is known about the links between its domestic and international trade. We attempt to quantify this relationship by comparing bird trade data on the CITES database with past market surveys of pet shops, complemented with semi-structured interviews with 30 parrot owners in Singapore. We report a decline in total imports and exports of CITES-listed birds in Singapore from 2005 to 2016, consistent with global trends after the European Union trade ban on wild bird imports. However, parrots continue to make up the majority of total imports; and there was a yearly increase in the percentage of parrot imports out of total imports. In addition, we report a difference in imports and exports of 54,207 CITES I, II and III listed birds into Singapore i.e. birds imported but not re-exported. A substantial proportion of these birds were possibly channelled into the domestic pet trade or used as breeding stock. Interviews with parrot owners confirmed the growing demand and popularity of parrots and particularly of larger species. We conclude that the domestic demand for parrots may have been previously underestimated, and make recommendations to manage Singapore’s international and domestic pet bird trade such as implementing a licensing and records system to track the movement of birds.
Background: Seizures are rare in REM sleep. To our knowledge, the effects of different sleep stages in anti-NMDA encephalitis have not been studied. Methods: Case report. Results: 32 year-old healthy female presented with acute fluctuating level of consciousness with episodic impulsivity, disorientation, and emotional outbursts following 3 days of headache. Her temperature was 37.8°C and she was started on ceftriaxone, vancomycin, and acyclovir. CSF only showed a total nuclear cell count of 182 and pleocytosis. MRI revealed increased T2 hyperintense right lateral temporal and parietal cortical thickening. EEG revealed right frontotemporal seizures with left sided rhythmic jerking, and an extreme delta brush pattern. Interestingly, seizures and extreme delta brush disappeared in REM sleep. After HSV PCR was negative, she was immunosuppressed with corticosteroids, IVIG, rituximab, and cyclophosphamide, given the extreme delta brush pattern. Repeat CSF analysis eventually yielded highly positive anti-NMDA antibodies. Ten weeks later, she became seizure free. Conclusions: For the first time, we report REM sleep in a case of anti-NMDA encephalitis during which there was absence of extreme delta brush and ictal EEG patterns. This observation may provide insight into the ongoing debate over whether extreme delta brush is an ictal EEG pattern.
We describe two cases of spontaneous embolisation and successful retrieval of ceramic-coated patent arterial duct devices. In both, the device embolised to the descending aorta in the absence of pulmonary hypertension and despite optimum placement. We have discussed possible mechanisms for embolisation in these patients and suggested alternative methods for device retrieval. Based on this limited experience, we conclude that for tubular ducts, ceramic-coated devices should be oversized to form a tighter waist or alternate devices may be considered.
Obsessive-compulsive disorder (OCD) is an anxiety disorder with significant morbidity whose pathophysiology is not fully understood. Neuroimaging studies have characterized OCD in terms of elevated striatal and prefrontal reactivity to emotion provocation. This neural model may be informed by investigation of functional connectivity in OCD, identifying alterations in how sensory information is integrated into frontostriatal regions.
The current study employed functional magnetic resonance imaging (fMRI) to compare neural activity and connectivity in 31 OCD patients (12 washing and 19 checking subtypes) and 17 healthy volunteers in an emotion provocation paradigm using visual stimuli.
OCD status was associated with hyper-activation of the posterior cingulate (PCg) in response to emotion provocation. Additionally, OCD patients demonstrated elevated PCg functional connectivity with the visual cortices and frontostriatal regions. Exploratory analyses suggested that stimulus-provoked activity and connectivity was elevated for checking subtypes in motor cortices, and elevated in washing subtypes in the anterior insula and orbitofrontal cortex.
The PCg's role in moderating connectivity between the visual cortex and frontolimbic regions is muted in OCD, consistent with the PCg's suggested role in regulating attention towards emotional stimuli. Exploratory analyses suggest distinct PCg connectivity profiles in OCD subtypes, with checking linked to motor activation, but washing linked to a network supporting emotional salience. The study was not powered to fully investigate the effects of medication, patients often endorsed secondary symptom subtypes that muddied washing/checking distinctions, and the emotion provocation paradigm was of limited intensity compared to life stressors.
One of the challenges with initiating long-acting injectable (LAI) antipsychotic regimens is achieving relevant drug levels quickly. After first injection of the LAI antipsychotic aripiprazole lauroxil (AL), the lag to reaching relevant plasma aripiprazole levels was initially addressed using supplemental oral aripiprazole for 21 days. A 1-day AL initiation regimen using a NanoCrystal® Dispersion formulation of AL (ALNCD; Aristada Initio®) combined with a single 30 mg dose of oral aripiprazole has been developed as an alternative approach. We compared the 1-day AL initiation regimen (ALNCD + 30 mg oral aripiprazole for 1 day) with the 21-day AL initiation regimen (AL + 15 mg/day of oral aripiprazole for 21 days) using kinetic modeling. Observed and modeled data demonstrate that the 1-day AL initiation regimen provides continuous aripiprazole exposure comparable to the 21-day AL initiation regimen. Each component of the 1-day AL initiation regimen (30 mg oral aripiprazole, ALNCD, and AL) contributes to aripiprazole plasma levels at different times, with oral aripiprazole predominating in the first week, then ALNCD and AL over time. In a double-blind, placebo-controlled, phase 1 study in patients with schizophrenia, the 1-day initiation regimen resulted in rapid achievement of relevant plasma aripiprazole levels comparable to those from the 21-day initiation regimen. Safety and tolerability of the 1-day regimen were consistent with the known profile of aripiprazole. Each part of the 1-day initiation regimen, together with AL, is necessary for continuous aripiprazole exposure from treatment initiation until the next regularly scheduled AL injection is administered.
Whereas genetic susceptibility increases the risk for major depressive disorder (MDD), non-genetic protective factors may mitigate this risk. In a large-scale prospective study of US Army soldiers, we examined whether trait resilience and/or unit cohesion could protect against the onset of MDD following combat deployment, even in soldiers at high polygenic risk.
Data were analyzed from 3079 soldiers of European ancestry assessed before and after their deployment to Afghanistan. Incident MDD was defined as no MDD episode at pre-deployment, followed by a MDD episode following deployment. Polygenic risk scores were constructed from a large-scale genome-wide association study of major depression. We first examined the main effects of the MDD PRS and each protective factor on incident MDD. We then tested the effects of each protective factor on incident MDD across strata of polygenic risk.
Polygenic risk showed a dose–response relationship to depression, such that soldiers at high polygenic risk had greatest odds for incident MDD. Both unit cohesion and trait resilience were prospectively associated with reduced risk for incident MDD. Notably, the protective effect of unit cohesion persisted even in soldiers at highest polygenic risk.
Polygenic risk was associated with new-onset MDD in deployed soldiers. However, unit cohesion – an index of perceived support and morale – was protective against incident MDD even among those at highest genetic risk, and may represent a potent target for promoting resilience in vulnerable soldiers. Findings illustrate the value of combining genomic and environmental data in a prospective design to identify robust protective factors for mental health.
Dicationic cobalt(II) complexes of the type [Co(fterpy)2]c(X)2·nH2O·mCH3OH (fterpy = 4′-(2-furyl)-2,2′:6′,2″-terpyridine; 1: X = PF6-, n = 1.5, m = 0; 2: X = ClO4-, n = 1, m = 1) have been isolated using self-assembly method and characterized by various spectroscopic techniques. In crystalline states both compounds exhibit gradual and incomplete spin crossover (SCO) behaviour in the temperature range 2-320 K. Various spin states of cobalt(II) in 1 have been confirmed by crystallographic evidences at 150 K and 293 K. A variation in counter anions and solvent molecules from 1 to 2 substantially improves the cooperativity among the spin active metal centres and thereby changing the nature of SCO behaviour.
Nearly three decades after the Cold War, the present-day hostilities between India and Pakistan have shifted the focus of the threat of nuclear escalation to South Asia. It is in this context that this article seeks to assess the legality of India’s military nuclear doctrine under international law.
Academic literature on the use of nuclear weapons has largely shied away from discussing the legality of specific military doctrines or ‘policies of deterrence’ of the nuclear weapon states, treating them as issues of military strategy that are beyond the realm of international law. This article hopes to challenge that dichotomy.
Though several branches of international law are relevant to any discussion on nuclear weapons, this article shall only examine India’s nuclear doctrine through the lens of jus ad bellum. Specifically, this article shall focus on whether India’s nuclear doctrine constitutes a threat to use force, and if so, whether such threat is lawful. The article concludes that India’s nuclear doctrine can be construed to be a specific threat to use force against Pakistan, and that such threat may be unlawful for contemplating the disproportionate use of force.
Cubic gallium nitride (GaN) is a wide bandgap semiconductor that exhibits a high crystallographic symmetry resulting in a lower inbuilt polarization which is useful for more efficient phosphor-free green light-emitting diodes. It has been grown using molecular beam epitaxy (MBE) and metal-organic chemical vapor deposition (MOCVD), which produce highly ordered thin films on compatible substrates. In this work, we report the chemical synthesis of GaN using chemical metathesis reaction in diethyl ether with lithium nitride and anhydrous gallium chloride as precursors, inside a nitrogen glove box at the room temperature. The resulting product was subsequently washed to remove lithium chloride and dried before vacuum annealing in a furnace at 850°C. Powder X-ray diffraction (XRD) scans of the as-prepared and annealed product reveal a mixed phase of GaN along with Ga2O3. Energy dispersive X-ray spectroscopy (EDAX) measurements show a nitrogen-poor product, which correlates well with the nearly black color of the powder. Diffuse reflectance spectroscopy (DRS) measurements were carried out with the obtained product on a barium sulfate substrate in a Perkin-Elmer Lambda 1050-UV-Vis-NIR spectrophotometer showing a strong absorbance below 400 nm. The energy band gap is bounded by values extracted from the Tauc plot and DRS measurements in the range of 3.2-3.5 eV, which is in good agreement with the known excitonic bandgap of cubic GaN (∼ 3.3 eV). Initial photoluminescence (PL) measurements using a Perkin-Elmer LS-55 spectrophotometer with an excitation wavelength of 310 nm reveal a weak emission centered around 440 nm corresponding to the known defect centers (D0X) in GaN. Further development of this process to form inks is expected to provide an alternate pathway to producing flexible phosphor-free lighting devices.
In this paper, a compact, low-profile, coplanar waveguide-fed metamaterial inspired dual-band microstrip antenna is presented for Wireless Local Area Network (WLAN) application. To achieve the goal a triangular split ring resonator is used along with an open-ended stub. The proposed antenna has a compact size of 20 × 24 mm2 fabricated on an FR-4 epoxy substrate with dielectric constant (εr) 4.4. The antenna provides two distinct bands I from 2.40 to 2.48 GHz and II from 4.7 to 6.04 GHz with reflection coefficient better than −10 dB, covering the entire WLAN (2.4/5.2/5.8 GHz) band spectrum. The performance of the proposed metamaterial inspired antenna is also studied in terms of the radiation pattern, efficiency, and the realized gain. A comparative study is also presented to show the performance of the proposed metamaterial inspired antenna with respect to other conventional antenna structures in terms of overall size, bandwidth, gain, and reflection coefficient. Finally, the antenna is fabricated and tested. The simulated results show good agreement with the measured results.