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Knowledge of proper clinical management of drug overdose and chemical and biological toxin exposure is important for the neurocritical care specialist. Many of the common offenders principally affect the central nervous system (CNS). Even those that do not will lead to a severely incapacitated state when overdosed such that the afflicted patient will require critical care in an intensive care unit (ICU).
This is a copy of the slides presented at the meeting but not formally written up for the volume.
Interactions at magnetic interfaces are central to the operation of virtually all magnetic heterostructures. When the interface is between two magnetic materials, the exchange interaction between spins at the interface is often a dominant force, and can dramatically change the magnetic response of the overall heterostructure. In ferromagnet (FM)/antiferromagnet (AFM) heterostructures, this interaction is often referred to as exchange anisotropy or bias and it has been widely used over the past decade in a wide array of applications such as magnetic recording heads, MRAMs, etc. The powerful implications of interactions between an AFM and a FM have been realized in a wide range of thin film heterostructure with both metallic and oxide constituents. There is, however, much less work on oxide-oxide FM/AFM systems. On the other hand, the development and understanding of functional oxide materials, especially multifunctional materials like BiFeO3 (BFO), have piqued the interest of researchers worldwide with the promise of coupling between order parameters such as ferroelectricity and antiferromagnetism. Recent research suggests that there is exchange coupling and anisotropy between the metallic ferromagnet Co0.9Fe0.1 (CoFe) and the multiferroic, antiferromagnet BFO, showing the possibility to create highly desirable multifunctional systems with new possibilities for device design. Such a result provides the driving force to create multifunctional oxide-oxide systems where exchange interactions could be much stronger then in metal/oxide structures due the added epitaxial nature of the interface. In this study, we use La0.7Sr0.3MnO3(LSMO)/BFO thin film heterostructures as a model system to explore the exchange interaction at an oxide interface. The heterostructures are grown on various vicinal cuts of SrTiO3 single crystal substrates using laser MBE. Structural analysis using x-ray diffraction, transmission electron microscopy and Rutherford backscattering spectrometry reveals high quality films with the pristine interfaces required for exchange coupling. First results from photoemission electron microscope (PEEM) studies reveal that the magnetic LSMO domain structure mimics underneath ferroelectric BFO domain structure, i..e, it is strongly pinned by the underlying AFM structure. The coupling behavior is being characterized by magnetic measurements (SQUID, VSM), which shows a strong enhancement in the coercivity of the LSMO layer, suggesting the existence of exchange bias coupling. We are probing the strength of this coupling using a combination of careful laser MBE growth experiments and physical property measurements. In this paper, we will report results of experiments in which the LSMO layer has been grown by laser MBE in the thickness range of 2-50nm on a  BFO layer.
Evidence on long-term influences of maternal vitamin B12 deficiency or concentrations on infant cognition is limited. We examined associations between maternal plasma vitamin B12 and cognitive development in 24-month-old infants. Maternal plasma vitamin B12 concentrations were measured at 26–28 weeks’ gestation; infant cognitive development was assessed with the Bayley Scales of Infant and Toddler Development-III at 24 months, for 443 mother–infant pairs from the Growing Up in Singapore Towards Healthy Outcomes cohort. Linear regressions adjusted for key confounders examined associations of maternal vitamin B12 with cognitive, receptive and expressive language, fine and gross motor subscales. Co-occurrence of maternal vitamin B12 with folate or vitamin B6 insufficiencies on child’s cognition was explored. Average maternal plasma vitamin B12 concentrations was 220·5 ± 80·5 pmol/l; 15 % and 41 % of mothers were vitamin B12 deficient (<148 pmol/l) and insufficient (148–220·9 pmol/l), respectively. Infants of mothers with vitamin B12 deficiency had 0·42 (95 % CI −0·70, −0·14) sd lower cognitive scores, compared with infants of mothers with sufficient vitamin B12. Co-occurrence of maternal vitamins B12 and B6 insufficiencies was associated with 0·37 (95 % CI −0·69, −0·06) sd lower cognitive scores in infants compared with infants of mothers sufficient in both vitamins. No significant associations were observed with other subscales. Study findings suggest the possible need to ensure adequate vitamin B12 during pregnancy. The impact of co-occurrence of maternal B-vitamins insufficiencies on early cognitive development warrants further investigation.
Silk and carbon nanomaterials, such as graphene oxide, graphene, and carbon nanotubes, have complementary mechanical properties that feature superior toughness and strength, respectively. Different strategies have been devoted to developing silk/carbon nanocomposites, but challenges remain to fully integrate the mechanical advantages of these two components into one synergistic material system. In this article, we provide a critical summary of structure–mechanics relationships in silk/carbon nanocomposites and highlight the impact of the interaction between silk and carbon nanomaterials on mechanical properties of the hybrid materials. We describe the challenges involved and directions for future designs of silk/carbon nanocomposites.
Mastery of strengthening strategies to achieve high-capacity anodes for lithium-ion batteries can shed light on understanding the nature of diffusion-induced stress and offer an approach to use submicro-sized materials with an ultrahigh capacity for large-scale batteries. Here, we report solute strengthening in a series of silicon (Si)–germanium (Ge) alloys. When the larger solute atom (Ge) is added to the solvent atoms (Si), a compressive stress is generated in the vicinity of Ge atoms. This local stress field interacts with resident dislocations and subsequently impedes their motion to increase the yield stress in the alloys. The addition of Ge into Si substantially improves the capacity retention, particularly in Si0.50Ge0.50, aligning with literature reports that the Si/Ge alloy showed a maximum yield stress in Si0.50Ge0.50. In situ X-ray diffraction studies on the Si0.50Ge0.50 electrode show that the phase change undergoes three subsequent steps during the lithiation process: removal of surface oxide layer, formation of cluster-size Lix(Si,Ge), and formation of crystalline Li15(Si,Ge)4. Furthermore, the lithiation process starts from higher index facets, i.e., (220) and (311), then through the low index facet (111), suggesting the orientation-dependence of the lithiation process in the Si0.50Ge0.50 electrode.
While studies suggest that nutritional supplementation may reduce aggressive behavior in children, few have examined their effects on specific forms of aggression. This study tests the primary hypothesis that omega-3 (ω-3), both alone and in conjunction with social skills training, will have particular post-treatment efficacy for reducing childhood reactive aggression relative to baseline.
In this randomized, double-blind, stratified, placebo-controlled, factorial trial, a clinical sample of 282 children with externalizing behavior aged 7–16 years was randomized into ω-3 only, social skills only, ω-3 + social skills, and placebo control groups. Treatment duration was 6 months. The primary outcome measure was reactive aggression collected at 0, 3, 6, 9, and 12 months, with antisocial behavior as a secondary outcome.
Children in the ω-3-only group showed a short-term reduction (at 3 and 6 months) in self-report reactive aggression, and also a short-term reduction in overall antisocial behavior. Sensitivity analyses and a robustness check replicated significant interaction effects. Effect sizes (d) were small, ranging from 0.17 to 0.31.
Findings provide some initial support for the efficacy of ω-3 in reducing reactive aggression over and above standard care (medication and parent training), but yield only preliminary and limited support for the efficacy of ω-3 in reducing overall externalizing behavior in children. Future studies could test further whether ω-3 shows promise in reducing more reactive, impulsive forms of aggression.
Among the most abundant biopolymers in the biosphere, lignin represents an untapped opportunity to create novel bioproducts. In this article, we discuss possibilities to synthesize nano- and microparticles by harnessing lignin’s inherent tendency to associate and to develop new material compositions and functions by controlling its capacity to assemble into supramolecular structures. Because lignin is biodegradable, antimicrobial, antioxidative, and carbon neutral, inexpensive industrial lignin streams could generate value-added particulate materials that preserve the structure, composition, and colloidal features inherent to this macromolecule. We present available routes for synthesis or isolation of lignin particles, including antisolvent and aerosol processing. Metallic and polymeric lignin particle hybrids for magnetic, antibacterial, catalytic, photonic, and other applications are also discussed. Overall, the facile formation of nano- and microparticles from lignins is expected to open new pathways toward future material development.
Public health bodies in many countries are attempting to increase population-wide habitual consumption of whole grains. Limited data on dietary habits exist in Singaporean children. The present study therefore aimed to assess whole grain consumption patterns in Singaporean children and compare these with dietary intake, physical activity and health parameters. Dietary intake (assessed by duplicate, multipass, 24-h food recalls), physical activity (by questionnaire) and anthropometric measurements were collected from a cross-section of 561 Singaporean children aged 6–12 years. Intake of whole grains was evaluated using estimates of portion size and international food composition data. Only 38·3 % of participants reported consuming whole grains during the dietary data collection days. Median intake of whole grains in consumers was 15·3 (interquartile range 5·4–34·8) g/d. The most commonly consumed whole-grain food groups were rice (29·5 %), wholemeal bread (28·9 %) and ready-to-eat breakfast cereals (18·8 %). A significantly lower proportion of Malay children (seven out of fifty-eight; P < 0·0001) consumed whole grains than children of other ethnicities. Only 6 % of all children consumed the amount of whole grains most commonly associated with improved health outcomes (48 g/d). There was no relationship between whole grain consumption patterns and BMI, waist circumference or physical activity but higher whole grain intake was associated with increased fruit, vegetable and dairy product consumption (P < 0·001). These findings demonstrate that consumption of whole grain foods is low at a population level and infrequent in Singaporean children. Future drives to increase whole-grain food consumption in this population are likely to require input from multiple stakeholders.
Nutrient deficiencies during childhood have adverse effects on child growth and health. In a single-arm 48-week long-term intervention, we previously reported the efficacy of oral nutritional supplementation (ONS) and dietary counselling on catch-up growth and growth maintenance in nutritionally at-risk Filipino children. The present analysis was done to assess the contributing effects of ONS to nutritional adequacy, dietary diversity, food intake and longitudinal growth. ONS (450 ml) was consumed daily providing 450 kcal (1880 kJ) and at least 50 % of micronutrient requirements among 200 children aged 3–4 years with weight-for-height percentiles between 5th and 25th (WHO Growth Standards). Weight, height and dietary intakes using 24-h food recalls were measured at baseline, and at weeks 4, 8, 16, 24, 32, 40 and 48. Nutrient adequacy and dietary diversity score (DDS) were calculated. Generalised estimating equations were used to assess the effects of total nutrient intakes, DDS, ONS compliance and sociodemographic factors on longitudinal growth. The percentages of children with adequate intake of energy, protein, Fe, Ca and some vitamins at each post-baseline visit were improved from baseline, reaching 100 % for most nutrients. DDS was also increased from baseline and reached significance from week 16 onwards (P < 0·01). Male children, total energy intake and parental employment status were associated with weight-for-height percentile gain (P < 0·05), whereas higher parental education level and ONS compliance were significantly associated with height-for-age percentile gain over time (P < 0·05). Long-term ONS intervention did not interfere with normal food intake and helped promote nutritional adequacy and growth of Filipino children.
Not every book sent for review comes with two pages of endorsements from the great and the good. Stokely is accompanied by glowing approval from such familiar names as Henry Louis Gates, Cornel West, Robin D. G. Kelley, Michael Eric Dyson, Gerald Horne, Charles Oglethorpe, and David Levering Lewis. Even without the para-textual apparatus to guide one's judgement, however, there is enough in this biography of Stokely Carmichael for any scholar of the civil rights movement to relish. This may not be the “definitive biography” that John Stauffer declares it to be, but it is indisputably important. In essence, Joseph argues that Stokely is the missing panel in a triptych of heroes, flanked on either side by the already canonized Malcolm X and Martin Luther King. In key respects, he insists, Stokely was the synthesis of Malcolm and Martin.
Vector-borne diseases are one of the world's major public health threats and annually responsible for 30–50% of deaths reported to the national notifiable disease system in China. To control vector-borne diseases, a unified, effective and economic surveillance system is urgently needed; all of the current surveillance systems in China waste resources and/or information. Here, we review some current surveillance systems and present a concept for an integrated surveillance system combining existing vector and vector-borne disease monitoring systems. The integrated surveillance system has been tested in pilot programmes in China and led to a 21·6% cost saving in rodent-borne disease surveillance. We share some experiences gained from these programmes.
Biomimetic hierarchical surface structures that exhibit features having multiple length scales have been used in many technological and engineering applications. Their surface topographies are most commonly analyzed using scanning electron microscopy (SEM), which only allows for qualitative visual assessments. Here we introduce fractal and lacunarity analyses as a method of characterizing the SEM images of hierarchical surface structures in a quantitative manner. Taking femtosecond laser-irradiated metals as an example, our results illustrate that, while the fractal dimension is a poor descriptor of surface complexity, lacunarity analysis can successfully quantify the spatial texture of an SEM image; this, in turn, provides a convenient means of reporting changes in surface topography with respect to changes in processing parameters. Furthermore, lacunarity plots are shown to be sensitive to the different length scales present within a hierarchical structure due to the reversal of lacunarity trends at specific magnifications where new features become resolvable. Finally, we have established a consistent method of detecting pattern sizes in an image from the oscillation of lacunarity plots. Therefore, we promote the adoption of lacunarity analysis as a powerful tool for quantitative characterization of, but not limited to, multi-scale hierarchical surface topographies.
Many electricity market participants have a requirement to calculate the probabilistic risk measures, such as earnings at risk (EaR) and value at risk (VaR), for compliance reporting purposes. This requirement is currently hindered by the lack of analytical representations for forecasts of demand (load) and price curves; this motivates numerical simulation and models that need extensive calibration. In this paper, we derive an analytical representation of a state demand forecast which is the aggregated usage of all electricity consumers in a particular region (such as New South Wales or Victoria). We have used two probabilistic benchmarks from the Australian energy market operator as input, which are expressed as forecasted probability of exceedance.
Due to a number of considerations, including asymmetry of these quantiles with respect to the median, we have selected a series of truncated lognormal distributions with two parameters. The procedure of finding these parameters has been reduced to solving (for every half-hour) a single nonlinear equation. As a result, the two-year half-hourly forecast (expected curve) and demand volatility are found by explicit integration with the set of derived distributions. We have also tested an alternative method based on simplifying assumptions; using a nontruncated lognormal distribution, we found that under the test conditions this method produces an identical forward load and volatility curve.
Rice (Oryza sativa L.) is one of the most important cereal crops in the world and a potentially important source of zinc (Zn) in the diet. The improvement of Zn content of rice is a global challenge with implications for both rice production and human health. The objective of the present study was to identify the effects of nitrogen (N) fertilizer rates and Zn application methods on Zn content of rice by evaluating rice production on native soils with different Zn availabilities in 2010/11. The results indicated that Zn application increased rice grain yield and Zn content in grains compared with the control; however, this effect was also affected by the native soil Zn availability, N fertilizer rate and Zn fertilizer application method. The native soil Zn status was the dominant factor influencing grain yield and grain Zn content in response to Zn fertilizer application. Grain Zn content ranged from 19·74 to 26·93 mg/kg under the different Zn statuses. The results also indicated that Zn application method has a significant influence on grain yield. Application of Zn fertilizer to the soil was more effective than the foliar spray on rice grain yield; however, the foliar spray resulted in a greater increase in grain Zn content when compared with soil application. Grain Zn content was affected by application method and displayed the following general trend: soil application + foliar spray > foliar spray > soil application. The experiments investigating the effect of N fertilizer rate combined with Zn application method showed a clear increase in both grain yield and Zn content as the N fertilizer level increased from 200 to 300 kg/ha. In addition, the results also indicated that N content and accumulation increased in all plant tissues, which suggests that Zn application might influence the uptake and translocation of N in rice plants. These results suggest that soil application in addition to a foliar spray of Zn should be considered as an important strategy to increase grain yield and grain Zn content of rice grown in soils with low background levels of Zn-associated diethylene triamine pentaacetate acid. Moreover, this process could be further strengthened by a high N application rate. In conclusion, these results demonstrate the potential of optimizing nutrient management using Zn fertilizer to obtain higher grain yields and higher grain Zn content in fields with low native Zn status.
Until recently, the analysis of polymer laminates using infrared microspectroscopy involved the painstaking separation of individual layers by dissection or by obtaining micrometer thin cross-sections. The latter usually requires the expertise of an individual trained in microtomy and even then, the very structure of the laminate could affect the outcome of the spectral results. The recent development of attenuated total internal reflection (ATR) infrared microspectroscopy imaging has provided a new avenue for the analysis of these multilayer structures. This report compares ATR infrared microspectroscopy imaging with conventional transmission infrared microspectroscopy imaging. The results demonstrate that the ATR method offers improved spatial resolution, eliminates a variety of competing optical processes, and requires minimal sample preparation relative to transmission measurements. These advantages were illustrated using a polymer laminate consisting of 11 different layers whose thickness ranged in size from 4–20 μm. The spatial resolution achieved by using an ATR-FTIR (Fourier transform infrared spectroscopy) imaging technique was diffraction limited. Contrast in the ATR images was enhanced by principal component analysis.
Organ shortage is a severe challenge worldwide. Three-dimensional (3D) printing, a rapidly developing engineering and materials science tool, holds considerable promise in generating implantable organ scaffolds that may reduce or eliminate organ shortage. However, translation of 3D printing into clinical therapies has been astonishingly slow and certainly has not matched the pace of technology development. This review outlines challenges and opportunities for the application of 3D printing in tissue and organ regeneration, with emphasis on in vivo applications of 3D-printed scaffolds. Three-dimensional-printed scaffolds for the regeneration of complex tissues and organs, including bone, cartilage, tooth, and skin, serve as prototypes for 3D printing of other tissues and organs such as the liver, kidney, or heart. The aspiration to reduce or eliminate organ shortage appears to hinge on the translation of 3D bioprinting technologies into preclinical studies and clinical trials. The remaining challenges of cell survival, directed differentiation, angiogenesis, and metabolic exchange are far from trial and need to be addressed. Three-dimensional-printed materials will remain a biomaterials and engineering showcase unless applications in preclinical and clinical models are realized. In balance, 3D printing holds considerable promise in regenerative medicine as a unique approach to address organ shortage.
Early life environments interact with genotype to determine stable phenotypic outcomes. Here we examined the influence of a variant in the brain-derived neurotropic factor (BDNF) gene (Val66Met), which underlies synaptic plasticity throughout the central nervous system, on the degree to which antenatal maternal anxiety associated with neonatal DNA methylation. We also examined the association between neonatal DNA methylation and brain substructure volume, as a function of BDNF genotype. Infant, but not maternal, BDNF genotype dramatically influences the association of antenatal anxiety on the epigenome at birth as well as that between the epigenome and neonatal brain structure. There was a greater impact of antenatal maternal anxiety on the DNA methylation of infants with the methionine (Met)/Met compared to both Met/valine (Val) and Val/Val genotypes. There were significantly more cytosine–phosphate–guanine sites where methylation levels covaried with right amygdala volume among Met/Met compared with both Met/Val and Val/Val carriers. In contrast, more cytosine–phosphate–guanine sites covaried with left hippocampus volume in Val/Val infants compared with infants of the Met/Val or Met/Met genotype. Thus, antenatal Maternal Anxiety × BDNF Val66Met Polymorphism interactions at the level of the epigenome are reflected differently in the structure of the amygdala and the hippocampus. These findings suggest that BDNF genotype regulates the sensitivity of the methylome to early environment and that differential susceptibility to specific environmental conditions may be both tissue and function specific.