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Spin coating and drop casting are viable methods for rapid and low-cost additive manufacturing of components for flexible devices and sensors. We investigated the cumulative effects of layering a conductive polymer composite 2 wt% MWCNT filler in PEDOT:PSS on a Mylar substrate for application to electromagnetic interference (EMI) shielding. The optical transmittace of spin coated composite layers is 90%, 45%, and 20% with a thickness of 0.05 µm, 0.15 µm, and 0.45 µm respectively. Drop cast composite layers have 0% transmittance due to their much greater starting thickness of 4.4 µm. The addition of isopropyl alcohol (IPA) to the solution mixture and substrate heating to 40 °C improves the conductivity, and drying time of the cured composite layers to 10 min. This study shows that the cumulative effects of composite layering are additive, but the electrical properties do not scale the same way. A significant increase in the EMI SE is mainly attributed to the enhanced electrical conductivity of the composite. The insertion of a 50 µm gap in between two 15 µm composite layers accentuates the EMI shielding effectiveness (SE) significantly to a peak of 21 dB within a narrow frequency range in the Ku-band tested.
Polymeric electrolytes have attracted recent research interest because they offer the advantages of being safe and non-flammable, having no dendrite formation, and having no possibility of leakage. The incorporation of synthetic polymers to gel electrolytes has numerous disadvantages: for instance, the required preparation time for creating gel electrolytes from synthetic polymers is dubious and lengthy. Additionally, the conventional pristine polymer gel electrolyte layer has been reported to have low ionic conductivity. This work is focused on preparing a thin flexible gel electrolyte layer by using a naturally occurring wood-based nanofiber cellulose (NFC) hydrogel, to overcome the energy and time consumption of conventional processes. In addition, we use polyvinyl alcohol (PVA) as an additive to the NFC hydrogel in controlled amounts to fabricate a stable thin gel electrolyte layer. By using x-ray diffraction, optical microscopy, and Fourier transform infrared spectra studies, we were able to further our understanding of the microstructure of the films: i.e., the penetration and cross-linking (changes in the bonding structures) of semi-crystalline PVA and hydrogel to form a flexible gel electrolyte layer. The NFC hydrogel-PVA films resulted in much higher ionic conductivity values when compared to other existing pristine polymer electrolytes. The addition of KOH to the NFC hydrogel-PVA further enhanced the ionic conductivity. The best ionic conductivity recorded was 75 mS/cm for films with thickness in the range of 200–350 µm, which is comparable to the highest reported ionic conductivity values of gel electrolytes.
Automatic cluster remover (ACR) settings regulate the end of milking by detaching the clusters based on milk flow dropping below a preset level, which needs to be standardised for different breeds of dairy animals based on their production. A study was conducted to find out the best ACR setting for milking Indian crossbred cows based on milkability, milking irregularities and milk quality. Fifty six crossbred dairy cows in lactations 1 to 4 were categorised into three groups based on the level of production; low (N = 16; <12 kg/d), medium (N = 32; 12–18 kg/d) and high (N = 08; >18 kg/d). The ACR settings tested were 0.1, 0.2, 0.3 and 0.4 kg/min, keeping the vacuum level and pulsation settings constant. The ACR settings significantly (P < 0.01) affected the milk yield at all levels of production with a significant effect (P < 0.01) on machine-on time at 0.4 kg/min. The yield during the first 2 min of milking, average flow and peak flow rates were not affected at any level of production. The average electrical conductivity in milk was significantly (P < 0.01) lower for the low and medium yield cows without affecting the mean somatic cell count. At 0.4 kg/min, more cluster reattachments were needed because of significant amount of milk remaining in the udders post-cluster removal.
We report the synthesis of a novel polymer gel electrolyte primarily based on cellulose extracted from wood along with gelatin, polyacrylic acid (PAA) and potassium hydroxide (KOH) added as additives in minute amounts in various stages. We also study and report the variation of ionic conductivity with variation of various additives. We found that, with variation of additives to hydrogel, its stability and degree of crystallinity are varied. The results were confirmed using x-ray diffraction and Fourier transform infrared spectra studies. An average best ionic conductivity of 96.89mS/cm was reported for a hydrogel: gelatin: PAA: KOH system, which is one of the best reported values of ionic conductivity for gel electrolytes.
Conventional approaches to evidence that prioritise randomised controlled trials appear increasingly inadequate for the evaluation of complex mental health interventions. By focusing on causal mechanisms and understanding the complex interactions between interventions, patients and contexts, realist approaches offer a productive alternative. Although the approaches might be combined, substantial barriers remain.
Declaration of interest
All authors had financial support from the National Institute for Health Research Health Services and Delivery Research Programme while completing this work. The views and opinions expressed therein are those of the authors and do not necessarily reflect those of the National Health Service, the National Institute for Health Research, the Medical Research Council, Central Commissioning Facility, National Institute for Health Research Evaluation, Trials and Studies Coordinating Centre, the Health Services and Delivery Research Programme or the Department of Health. S.P.S. is part funded by Collaboration for Leadership in Applied Health Research and Care West Midlands. K.B. is editor of the British Journal of Psychiatry.
Spent culture medium can provide valuable information regarding the physiological state of a bovine preimplantation embryos through non-invasive analysis of the sum/depleted metabolite constituents. Metabolomics has become of great interest as an adjunct technique to morphological and cleavage-rate assessment, but more importantly, in improving our understanding of metabolism. In this study, in vitro produced bovine embryos developing at different rates were evaluated using proton nuclear magnetic resonance (1H NMR). Spent culture medium from individually cultured embryos (2-cell to blastocyst stage) were divided into two groups based on their cleavage rate fast growing (FG) and slow growing (SG; developmentally delayed by 12–24 h), then analyzed by a 600 MHz NMR spectrometer. Sixteen metabolites were detected and investigated for sum/depletion throughout development. Data indicate distinct differences between the 4-cell SG and FG embryos for pyruvate (P < 0.05, n = 9) and at the 16-cell stage for acetate, tryptophan, leucine/isoleucine, valine and histidine. Overall sum/depletion levels of metabolites demonstrated that embryos produced glutamate, but consumed histidine, tyrosine, glycine, methionine, tryptophan, phenylalanine, lysine, arginine, acetate, threonine, alanine, pyruvate, valine, isoleucine/leucine, and lactate with an overall trend of higher consumption of these metabolites by FG groups. Principal component analysis revealed distinct clustering of the plain medium, SG, and FG group, signifying the uniqueness of the metabolomic signatures of each of these groups. This study is the first of its kind to characterize the metabolomic profiles of SG and FG bovine embryos produced in vitro using 1H NMR. Elucidating differences between embryos of varying developmental rates could contribute to a better understanding of embryonic health and physiology.
OBJECTIVES/SPECIFIC AIMS: The goal of this study is to use patient-centered qualitative techniques to determine what strategies caregivers use to cope with the stress of a child having recently (ie, within the past month) undergone surgical removal of a brain tumor. Results will eventually be evaluated and compared with results of quantitative measures of psychosocial risk and distress as well as demographic and medical characteristics. METHODS/STUDY POPULATION: All caregivers of patients with a newly diagnosed brain tumor requiring neurosurgery admitted to Children’s of Alabama (with English or Spanish-speaking parents) are eligible for enrollment. Participants are enrolled during their child’s initial hospitalization for surgical removal of a brain tumor. Approximately 1 month after hospital discharge, during a routine follow-up clinic visit, caregivers participate in a semistructured interview with a research assistant. Interview questions are used to obtain information about parent and family coping by asking first broadly about stress management over the previous month and then specifically about individual coping strategies. Semistructured interviews are audio recorded, transcribed, and coded for common themes. Interviews are coded by using specific words or phrases to describe various domains of the experience from the caregiver’s perspective. Each participant is given a study ID and study IDs are logged with each code word or phrase endorsed during the interview. RESULTS/ANTICIPATED RESULTS: To date, 22 caregivers have been enrolled and 15 have completed interviews. The most common coping mechanisms fall into the domains of active, avoidance, emotion-focused, and spiritual coping. Active coping consists of information seeking (eg, taking notes, internet research, asking questions), openly communicating emotions, celebrating small victories (eg, focusing on a good scan or test result, thinking that the diagnosis or treatment could have been worse), planning (eg, focusing on 1 d at a time), and maintaining normalcy (eg, maintaining extracurricular activities, returning to school if possible, continuing to see family and friends). Avoidance coping consists of evading discussions about emotions, withdrawal from family members, denial (eg, keeping a cancer diagnosis from the child), and avoiding seeing people or participating in activities. Emotion-focused coping consists of crying, laughing, and staying strong in front of the patient. In general, those who self-identify as coping poorly tend to be those who utilized more avoidance-focused coping strategies. Further, caregivers tended to identify active coping strategies (eg, taking notes, focusing on 1 appointment or treatment at a time) as the most helpful. DISCUSSION/SIGNIFICANCE OF IMPACT: It will be helpful for providers to more deeply understand the experience of caregivers whose children have recently undergone brain tumor resection and the strategies used to cope with the stress of the first month postsurgery. This information can be used to create standardized interventions for use during posthospitalization clinic visits. For example, if families continue to endorse that active coping mechanisms are the most helpful, providers can assist caregivers in developing these strategies (eg, uniformly provide notebooks and encourage caregivers to keep track of questions and appointment information, pair caregivers who are struggling with others who use more active coping strategies). Those utilizing more avoidance coping strategies may need more coaching and recommendations. A brief assessment could potentially be developed for caregivers dealing with this diagnosis, in order to quickly assess coping strategies and provide appropriate recommendations. Future analyses will determine whether initial coping strategies and adjustment are predicted by child age or medical information.
Deficiencies of micro (Zn, B) and secondary (S) nutrients are well-documented in soil as well as in cereal crops, leading to decreased crop yields and low nutritional quality of food. We evaluated the effects of coated urea on maize yield, N and Zn uptake, and input cost relationships. Field experiments were conducted on maize to test boron-coated (BCU), sulphur-coated (SCU) and zinc-coated urea (ZnCU) during 2013 and 2014. On the basis of 2 years’ average data, the highest grain yield was achieved with 0.5% BCU, 5% SCU and 2.5% ZnCU as zinc sulphate hepta hydrate. These treatments increased yields by 5.4, 12.8 and 9.9% over prilled urea (PU), respectively. Application of 0.5% BCU (supplying 1.4 kg B ha−1), 5% SCU (supplying 14.1 kg S ha−1) and 2.5% ZnCU (supplying 7.05 kg Zn ha−1) registered the highest N concentrations and uptake in grain and stover. Total N uptake (grain + stover) was increased by 7.6, 16.7 and 17.1% with BCU, SCU and ZnCU treatments over PU. As compared to PU, Zn concentration in maize grain was significantly higher and total Zn uptake (grain + stover) increased by 32.4% with 2.5% ZnCU. Coated urea materials also enhanced the partial factor productivity (PFPN), agronomic efficiency (AEN), recovery efficiency (REN) and harvest index (HIN) over those of PU. From the economic viewpoint this study suggests that coating of urea with 0.3% boron, 5% sulphur or 2% zinc gives maximum net returns and benefit-cost ratio. Our data indicate that coating of B, Zn and S onto urea increases maize yield, profitability and nitrogen use efficiency in the western Indo-Gangetic plains of India.
Topdressing of N fertilizer, whenever leaf greenness, as measured by Chlorophyllmeter (SPAD), falls below the threshold value can be used for site-specific N management in wheat cultivation. Herein, a field experiment was conducted to analyse the effect of SPAD-based N management on wheat productivity and N use efficiency during the dry season of 2010/11 and 2011/12 on acid lateritic soil of eastern India. The experiment had 12 treatments, with nine treatments combining three SPAD thresholds (38, 40 and 42) and three N levels (15, 25 and 35 kg N ha−1) as real time N management (RTNM), one fixed time N management (FTNM), one farmers’ fertilizer practise (FFP) and control (Zero N), with three replications. The grain yield of RTNM ranged from 90 to 113% as that of FTNM, but using considerably less N. Maintaining SPAD threshold of 40 up to heading stage by topdressing 25 kg N ha−1 at each time (N25S40) caused the highest grain yield (4483 kg ha−1). While saving 22.5 kg N ha−1 (18.8%), N25S40 increased agronomic N use efficiency by 58.5%, nitrogen recovery efficiency by 15.1% and partial factor productivity of applied N by 26.4% when compared with conventional fertilizer recommendations (i.e. FTNM). The SPAD-based N management strategy was found very promising in efficiently managing N fertilizer in wheat for improving wheat productivity and N use efficiency.
This is a comprehensive introduction to the brand new theory of conic finance, also referred to as the two-price theory, which determines bid and ask prices in a consistent and fundamentally motivated manner. Whilst theories of one price classically eliminate all risk, the concept of acceptable risks is critical to the foundations of the two-price theory which sees risk elimination as typically unattainable in a modern financial economy. Practical examples and case studies provide the reader with a comprehensive introduction to the fundamentals of the theory, a variety of advanced quantitative models, and numerous real-world applications, including portfolio theory, option positioning, hedging, and trading contexts. This book offers a quantitative and practical approach for readers familiar with the basics of mathematical finance to allow them to boldly go where no quant has gone before.
In this chapter we illustrate the conic finance theory in the setting of equitylinked insurance contracts. We elaborate on how to improve the risk profile and risk-manage such types of contracts (see also Carr et al. (2016)).
Insurance books often combine exposures to financial and non-financial risks, with the financial component often being quite complex and involving pathdependent aspects. Yet one anticipates that movements in security prices over the near term can have considerable effects on the present value of payouts associated with the insurance liabilities. Taking positions in the options markets of related securities may constitute a good hedge for the insurance book. The purpose here is to present a detailed methodology for constructing such option hedges. The purpose of the hedge is not that of replication or risk elimination, as this is not expected to be possible, but one of improving the overall quality of the position.
Implementation of the methodology requires an ability to simulate the paths, at a regular frequency, of relevant underliers and the associated present value of the related insurance cash flows. We introduce as hedging assets positions in the underlying stocks and out of the money options on these stocks. The residual position that we investigate is given by earnings on the hedge positions together with the present value of the insurance contract's cash flows. The hedge positions are sought in a way that makes the package more diversified. Diversity is measured by the gap between the ask price of the package and the sum of the ask prices of the components of the package.We hence face an optimization problem in the number of all options on all underliers plus the number of underliers for the stock positions. The hedge is designed to numerically solve this optimization problem.
We exemplify the methodology on Guaranteed Minimum Withdrawal Benefit Variable Annuities (GMWBVA). When such deals are struck, or more generally whenever these deals are on the books, they are exposed to market risk. Using a particular model, one can try to estimate this risk and, for example, estimate what the marked-to-market profit or loss would be if the underlying stock or index were to move.
In financial engineering there are essentially two different worlds. The so-called real world (sometimes also referred to as the historical or physical world or P-world) and the pricing world (sometimes also referred to as the risk-neutral world or Q-world). We recognize up-front that in markets every event has in principle both a probability or a likelihood of its occurrence and a price, i.e. the price of a security paying a dollar if the event occurs. If that price is paid at event resolution, the event price we speak of is then a forward price. These forward prices are non-negative, being claims to non-negative cash flows. The prices for disjoint or mutually exclusive events are additive by no-arbitrage. They sum to unity over a set of mutually exclusive and exhaustive events as the forward price of a dollar for certain is a dollar. Hence, prices of events behave like probabilities (pricing world) and the mathematics of probability applies to them, but they are not probabilities; they are forward prices. They can differ substantially from the probabilities of the events actually occuring (real world). A typical example is found in insurance, where the forward premium paid for life, fire or car insurance by a particular individual far exceeds the probability of the insured event. The potential personal damage caused by the event induces people in markets to pay more than the probability for coverage. Competitive pressures do not reduce prices to probability assessments as sufficiently large pools of identical risks may not be available, leaving sellers exposed to risk that must be compensated in the premium. In these two worlds, one looks differently to the stochastic behaviour of the assets under investigation; the prices of events seen as probabilities (pricing world) differ from the probabilities of the events happening in the real world.
Most of the time, the probability measuring how things happen in the real world is denoted with a P; therefore also this real world is often named the P-world.