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Silicon electrodes with the columnar macroporous structure were investigated to determine the effect of variations in the columnar pore morphology on lithiation and energy storage capacity in Li-ion cells. Several variants of macroporous Si columnar electrodes were electrochemically cycled against the Li reference electrode. The changes in macro-pore size and Si wall thickness of the columnar architecture greatly affected the cyclic Li storage and discharge capacities. A strong correlation of the Li-storage capacity with the ratio of Si wall thickness to pore diameter is found to exist. Specifically, one columnar Si electrode with an optimum macroporous structure exhibited a very high reversible specific capacity of ~1250 mAh/g (total capacity 1.2 mAh/cm2) for over 200 cycles. Electron microscopy revealed that the high reversible Li-storage capacity is due to the macropores accommodating the change in volume of lithiation and providing nearly complete reconstruction of Si walls upon delithiation. The present observations can lead to practical, high-capacity, and damage-resistant Si electrodes for Li-ion batteries.
To assess availability, variety, price and quality of different food products in a convenience sample of supermarkets in Germany and the USA.
Cross-sectional study using an adapted version of the Bridging the Gap Food Store Observation Form.
Information on availability, quality, price and variety of selected food products in eight German and seven US supermarkets (discount and full service) was obtained and compared by country.
A general tendency for lower prices of fruits and vegetables in Germany was observed, while produce quality and variety did not seem to differ between countries, with the exception of the variety of some vegetables such as tomatoes. Chips and cereals did not differ significantly in variety nor price. In both countries, high energy-dense foods were lower in energy costs than lower energy-dense foods.
The influence of food prices and availability on consumption should be further explored, including the impact of country differences.
Studies suggest that alcohol consumption and alcohol use disorders have distinct genetic backgrounds.
We examined whether polygenic risk scores (PRS) for consumption and problem subscales of the Alcohol Use Disorders Identification Test (AUDIT-C, AUDIT-P) in the UK Biobank (UKB; N = 121 630) correlate with alcohol outcomes in four independent samples: an ascertained cohort, the Collaborative Study on the Genetics of Alcoholism (COGA; N = 6850), and population-based cohorts: Avon Longitudinal Study of Parents and Children (ALSPAC; N = 5911), Generation Scotland (GS; N = 17 461), and an independent subset of UKB (N = 245 947). Regression models and survival analyses tested whether the PRS were associated with the alcohol-related outcomes.
In COGA, AUDIT-P PRS was associated with alcohol dependence, AUD symptom count, maximum drinks (R2 = 0.47–0.68%, p = 2.0 × 10−8–1.0 × 10−10), and increased likelihood of onset of alcohol dependence (hazard ratio = 1.15, p = 4.7 × 10−8); AUDIT-C PRS was not an independent predictor of any phenotype. In ALSPAC, the AUDIT-C PRS was associated with alcohol dependence (R2 = 0.96%, p = 4.8 × 10−6). In GS, AUDIT-C PRS was a better predictor of weekly alcohol use (R2 = 0.27%, p = 5.5 × 10−11), while AUDIT-P PRS was more associated with problem drinking (R2 = 0.40%, p = 9.0 × 10−7). Lastly, AUDIT-P PRS was associated with ICD-based alcohol-related disorders in the UKB subset (R2 = 0.18%, p < 2.0 × 10−16).
AUDIT-P PRS was associated with a range of alcohol-related phenotypes across population-based and ascertained cohorts, while AUDIT-C PRS showed less utility in the ascertained cohort. We show that AUDIT-P is genetically correlated with both use and misuse and demonstrate the influence of ascertainment schemes on PRS analyses.
It is becoming clear that post-traumatic stress disorder (PTSD) is not simply a psychiatric disorder, but one that involves pervasive physiological impairments as well. These physiological disturbances deserve attention in any attempt at integrative treatment of PTSD that requires a focus beyond the PTSD symptoms themselves. The physiological disturbances in PTSD range over many systems, but a common thread thought to underlie them is that the chronic effects of PTSD involve problems with allostatic control mechanisms that result in an excess in what has been termed “allostatic load” (AL). A pharmacological approach to reducing AL would be valuable, but, because of the large range of physiological issues involved – including metabolic, inflammatory, and cardiovascular systems – it is unclear whether there exists a simple comprehensive way to address the AL landscape. In this paper, we propose that the cannabinoid system may offer just such an approach, and we outline evidence for the potential utility of cannabinoids in reducing many of the chronic physiological abnormalities seen in PTSD which are thought to be related to excess AL.
Considerable attention has focused on tactics firms use when building their sustainability platforms. Less is known, however, about how sustainability goal setting varies globally, especially in developing economies. Accordingly, we examined sustainability goals of 21 of the 50 largest Indian firms and compared them with similar data from a published study that examined 22 of the 50 largest U.S. firms. In total, 679 sustainability goals were analyzed using a triple bottom line framework. We found U.S. firms set more sustainability goals than Indian firms. Firms from both samples set similar numbers of people goals but U.S. firms set more diversity goals. Indian firms were more inclined to set economic and community development goals. We also detected differences across the samples in planet goals associated with emissions and water. Especially significant, Indian firms were much more likely than U.S. firms to specify profit goals. Implications for research and practice are discussed.
Alterations in reinforcement-based decision making may be associated with increased psychiatric vulnerability in children who have experienced maltreatment. A probabilistic passive avoidance task and a model-based functional magnetic resonance imaging analytic approach were implemented to assess the neurocomputational components underlying decision making: (a) reinforcement expectancies (the representation of the outcomes associated with a stimulus) and (b) prediction error signaling (the ability to detect the differences between expected and actual outcomes). There were three main findings. First, the maltreated group (n = 18; mean age = 13), relative to nonmaltreated peers (n = 19; mean age = 13), showed decreased activity during expected value processing in a widespread network commonly associated with reinforcement expectancies representation, including the striatum (especially the caudate), the orbitofrontal cortex, and medial temporal structures including the hippocampus and insula. Second, consistent with previously reported hyperresponsiveness to negative cues in the context of childhood abuse, the maltreated group showed increased prediction error signaling in the middle cingulate gyrus, somatosensory cortex, superior temporal gyrus, and thalamus. Third, the maltreated group showed increased activity in frontodorsal regions and in the putamen during expected value representation. These findings suggest that early adverse environments disrupt the development of decision-making processes, which in turn may compromise psychosocial functioning in ways that increase latent vulnerability to psychiatric disorder.
Altered autobiographical memory (ABM) functioning has been implicated in the pathogenesis of depression and posttraumatic stress disorder and may represent one mechanism by which childhood maltreatment elevates psychiatric risk.
To investigate the impact of childhood maltreatment on ABM functioning.
Thirty-four children with documented maltreatment and 33 matched controls recalled specific ABMs in response to emotionally valenced cue words during functional magnetic resonance imaging.
Children with maltreatment experience showed reduced hippocampal and increased middle temporal and parahippocampal activation during positive ABM recall compared with peers. During negative ABM recall they exhibited increased amygdala activation, and greater amygdala connectivity with the salience network.
Childhood maltreatment is associated with altered ABM functioning, specifically reduced activation in areas encoding specification of positive memories, and greater activation of the salience network for negative memories. This pattern may confer latent vulnerability to future depression and posttraumatic stress disorder.
Giardiasis is a treatable disease, caused by the flagellated protozoan parasite, Giardia duodenalis (G. duodenalis). It is one of the most common enteric parasites found globally to cause gastrointestinal disturbances, and infections may result in long-term irritable bowel syndrome-like symptoms. It is a common misconception that giardiasis is associated with foreign travel, which results in locally acquired cases in the UK being underdiagnosed. This report highlights the findings from one large Scottish Health Board, arising from a change in testing methodology, which resulted in the screening of all stools submitted for enteric investigations for G. duodenalis. Previous selection criteria were restricted to patients with a travel history to specific regions of the world, or on the basis of certain clinical details. In this report, clinical details were recorded from samples shown to be positive using two methods: an ELISA-based antigen detection assay and microscopy. Clinical details were assessed for a total of 28 laboratory-confirmed positive cases against the original selection criteria. Twenty-six cases (93%) would have been excluded from Giardia testing if the previous selection criteria had been applied. Although nine cases stated foreign travel, only two had been to regions deemed to be ‘high risk’. Therefore, those seven cases that travelled to perceived ‘low-risk’ regions would have been excluded from testing for this reason. This summary highlights the need for significant improvements to the selection criteria for Giardia testing. Laboratories should be encouraged towards the testing of all routinely submitted stools for this neglected pathogen to ensure cases that are acquired locally are properly identified and treated effectively.
Programmatic learning goals serve as the foundation for an educational institution’s curriculum design and assurance of learning processes. The purpose of our study is to determine the relevance or alignment of undergraduate business school learning goals. We identify the learning goals of US undergraduate business programs accredited by the Association to Advance Collegiate Schools of Business-International (AACSB) and determine the extent to which the goals are aligned with (a) evidence-based competencies that are needed for managerial success (including the ‘Great Eight’ and the ‘hyperdimensional taxonomy’) and (b) content areas identified in AACSB’s Eligibility Procedures and Accreditation Standards for Business Accreditation. We found that learning goals conform to AACSB Standards and evidence-based managerial competencies, but goals are most closely aligned with AACSB Standards, followed by the Great Eight, and the hyperdimensional taxonomy, respectively. We discuss the implications of our findings with respect to business schools’ assurance of learning processes and provide recommendations for AACSB, business schools, the broader academy, and future research.
Giardia duodenalis and Cryptosporidium species are protozoan parasites capable of causing gastrointestinal disease in humans and animals through the ingestion of infective faeces. Whereas Cryptosporidium species can be acquired locally or through foreign travel, there is the mis-conception that giardiasis is considered to be largely travel-associated, which results in differences in laboratory testing algorithms. In order to determine the level of variation in testing criteria and detection methods between diagnostic laboratories for both pathogens across Scotland, an audit was performed. Twenty Scottish diagnostic microbiology laboratories were invited to participate with questions on sample acceptance criteria, testing methods, testing rates and future plans for pathogen detection. Reponses were received from 19 of the 20 laboratories representing each of the 14 territorial Health Boards. Detection methods varied between laboratories with the majority performing microscopy, one using a lateral flow immunochromatographic antigen assay, another using a manually washed plate-based enzyme immunoassay (EIA) and one laboratory trialling a plate-based EIA automated with an EIA plate washer. Whereas all laboratories except one screened every stool for Cryptosporidium species, an important finding was that significant variation in the testing algorithm for detecting Giardia was noted with only four laboratories testing all diagnostic stools. The most common criteria were ‘travel history’ (11 laboratories) and/or ‘when requested’ (14 laboratories). Despite only a small proportion of stools being examined in 15 laboratories for Giardia (2%–18% of the total number of stools submitted), of interest is the finding that a higher positivity rate was observed for Giardia than Cryptosporidium in 10 of these 15 laboratories. These findings highlight that the underreporting of Giardia in Scotland is likely based on current selection and testing algorithms.
Results are presented from our ongoing studies of Titan using ALMA during the period 2012-2015, including a confirmation of the previous detection of vinyl cyanide (C2H3CN), as well as the first spatial map for this species on Titan. Simultaneous mapping of HC3N, CH3CN and C2H5CN reveal characteristic abundance patterns for each species that provide insight into their individual photochemical lifetimes, and help inform our understanding of Titan’s unique, time-variable atmospheric chemistry and global circulation. A time-sequence of HC3N maps covering 38 months reveals a dramatic change in the distribution of this gas consistent with high-altitude photochemical production followed by advection towards the southern (winter) pole, combined with rapid loss in the north after Titan’s 2009 seasonal equinox. The 2015 C2H3CN and C2H5CN maps show abundance peaks in Titan’s southern hemisphere, similar to those observed for the short-lived HC3N molecule. The longer-lived CH3CN, on the other hand, remains more concentrated in the north.
The ultimate aim of any radar experiment is of course to determine information about the structures which backscatter the radio waves, and the environment in which they exist. For example, it might be of interest to study the wind speeds associated with the scatterers, or the shape of the scatterers, or to differentiate types of scatterers or reflectors. It might be of interest to determine the radar cross-section of the scatterers, or their spatial distribution over the sky. Other desired information might include the spatial and temporal variation of the scatterer velocities as a function of time and height. If the radio scatter is due to turbulence, it might be desirable to measure the intensity of the turbulence, and/or its spatial distribution. It might be of interest to determine the relative percentages of turbulent to non-turbulent scatter. The list can go on.
In the preceding chapters, we concentrated on: (i) the principles of radar (Chapters 2 to 6); (ii) signal processing procedures (Chapters 3 to 5); and (iii) the nature of the scattering mechanisms (especially Chapter 3). Now is the time to bring all this information together and look more closely at the interaction between the radar and its scattering environment. In particular, we want to determine how the radar may be used to deduce information about the scatterers themselves. This information could include all sorts of spatial scales, right down to the radar wavelength (often indirect information at such small scales), and a wide variety of temporal scales, from fractions of a second to many years.
The purpose of this chapter is therefore to discuss ways that relevant atmospheric parameters can be determined and then interpreted, in order to give new insights into the nature of the scatterers. We will re-examine some of the parameters already discussed, like spectral characteristics, and we will also introduce new ones, like the turbulence anisotropy, amplitude distributions, phase distributions, turbulence strengths, tropopause height, and so forth. Some of the approximations used in determining these parameters are also critically examined. Some consideration will be given to experimental design, and then interpretation of the results. Studies of the parameters evaluated over long periods of time can give a considerable amount of additional information, over and above that which can be determined from a few discrete observations, but discussion of this aspect will not be considered in great detail, due to lack of space.
This book is about designing, building, and using atmospheric radars. Of course the term “atmospheric radar” covers a wide and diverse set of instruments, which can be used to study a wide range of atmospheric phenomena, and we cannot cover all radar types nor all applications. However, radars used for MST (Mesosphere-Stratosphere-Troposphere) studies employ a very high percentage of the techniques used in atmospheric studies, and cover an extraordinary range of physical processes. Therefore we have chosen this field as our focus. A reader familiar with this book should not only have developed a broad comprehension of the MST region, but should be able to diversify easily to other fields of atmospheric radar work.
While the primary targets of this book are new and advanced graduate science and engineering students working with radar to study the atmosphere, we have also aimed to make it accessible and useful to a wider audience. The extensive references and diagrams should make it valuable as a general reference resource even for more experienced workers in the field. The level of difficulty in each chapter has been adapted to suit the standards of a student with a modest background in mathematics and signalprocessing. Some level of understanding of Fourier methods, including Fourier integrals, is desirable, although not mandatory. Nevertheless, some of the chapters are pitched at a level which could be followed even by an interested amateur. Chapter 2, for example, gives a moderately detailed history of the development of atmospheric radar, examining the development of experimental radio applications for both meteorology and world-wide communication following World War II, and would be of interest to, and easily comprehenced by, an enthusiastic radar hobbyist or history buff. Yet the detail on scatter processes in Chapter 3 in regard to the refractive index of the atmosphere and ionosphere should be enough to satisfy more discerning tastes in mathematical complexity.
The layout of the chapters has been carefully developed, mixing the areas of technical detail and practical application in a way that we hope will keep the reader stimulated as we develop parallel themes of radar engineering, experimental design, application and understanding of meteorological/atmospheric physics and chemistry.
We begin with an overview of the atmosphere which can easily be comprehended by a reader with no knowledge at all of radar.
It should be clear from the foregoing chapters that the range of applications of MST and windprofiler radar is broad and challenging. Some techniques are mature, some are under development, and some are even no doubt yet to be discovered. Measurements of wind velocities and, by extension, wave motions, wave-mean flow interactions, momentum flux deposition and turbulence, are possible. Capabilities for temperature measurements, and the possibility of humidity measurements, have been discussed. Strange echoes such as polar mesosphere summer echoes have given new insights into the plasma processes of the lower thermosphere. Studies of turbulence anisotropy are possible. We have demonstrated functional radar designs that cost as little as $100 000 up to many millions of dollars.
We will not dwell on these many achievements, however, which should be selfevident. What is perhaps of greater interest is the future of these instruments, and this will be the main focus here.
The future harbors both pragmatic and curiosity-driven aspects. From the point of view of the former, networks of radars, providing data for incorporation into computer forecasting and now-casting models, offer the hope of better forecasts. They have been shown to have benefits in forecasting on time-scales from a few hours out to several days, especially with systems deployed in Japan, Europe, and Canada (see Chapter 12). At the time of writing (2015), the European Space Agency is about to launch a specialized satellite instrument (AEOLUS) for measurement of tropospheric winds from space by lidar, and the networks of windprofilers discussed will be crucial tools for validation of these data. However, since the satellite only measures winds at sunrise and sunset, the radars, with their continuous recording capability, will continue to provide valuable input to meteorological models for many years to come.
Accurate records of winds are of course valuable for large-scale forecasts. This can impact aircraft travel, allowing better flight planning. The ability of radars to make reliable measurements of turbulence strengths can also be of value from the perspective of aircraft passenger safety.
As we have already discussed, there are many competing factors that must be taken into account in order to optimally investigate the atmosphere through radar observations. One of the more notable examples is the Doppler dilemma. Obviously one would like to select an inter-pulse period (IPP) corresponding to a sufficiently large Nyquist velocity interval. Here sufficiently large means a velocity range that encompasses most of the anticipated radial velocities to be observed. The range of Nyquist velocities is extended by decreasing the IPP. However, decreasing the IPP also reduces the maximum unambiguous range that can be measured. Ideally one would like to maintain a large Nyquist velocity (short IPP) and large maximum unambiguous range (long IPP) – hence the dilemma. Another example involves the disparity between the desire to improve range resolution and improve radar sensitivity. Range resolution can be improved by decreasing the radar pulse width; however, this means a decrease in the amount of power that illuminates a scatterer and corresponding decrease in detectability. That is, the desire to increase the detectability of atmospheric signals by transmitting longer radar pulses is at odds with the need to improve range resolution.
In many cases, techniques have been developed that allow us to work around the compromises that arise in designing radar experiments. For example, pulse compression (discussed in Chapter 4) is used to improve range resolution without compromising the signal-to-noise ratio (SNR) (Schmidt et al., 1979). By and large, such techniques are known to introduce corresponding undesirable side effects. For the case of pulse compression, either the existence of some level of range side-lobes, or a decrease in temporal resolution, are a by-product of complementary codes.
In this chapter, we discuss how the use of multiple-receiver and multiple-frequency techniques can be used in atmospheric remote sensing as a means of improving angular and range resolution respectively. Before proceeding, we should clarify one point of nomenclature. The term multiple-receiver will be used throughout this chapter to describe a radar system that is capable of receiving and recording atmospheric signals on two or more spatially separated antennas or groups of antennas. The myriad names associated with interferometric techniques were discussed in Chapter 2, Section 2.15.6: here, we will discuss in detail just a subset of these, but the points discussed will cover to some extent all the techniques.