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A mother's nutritional choices while pregnant may have a great influence on her baby's development in the womb and during infancy. There is evidence that what a mother eats during pregnancy interacts with her genes to affect her child's susceptibility to poor health outcomes including childhood obesity, pre-diabetes, allergy and asthma. Furthermore, after what an infant eats can change his or her intestinal bacteria, which can further influence the development of these poor outcomes. In the present paper, we review the importance of birth cohorts, the formation and early findings from a multi-ethnic birth cohort alliance in Canada and summarise our future research directions for this birth cohort alliance. We summarise a method for harmonising collection and analysis of self-reported dietary data across multiple cohorts and provide examples of how this birth cohort alliance has contributed to our understanding of gestational diabetes risk; ethnic and diet-influences differences in the healthy infant microbiome; and the interplay between diet, ethnicity and birth weight. Ongoing work in this birth cohort alliance will focus on the use of metabolomic profiling to measure dietary intake, discovery of unique diet–gene and diet–epigenome interactions, and qualitative interviews with families of children at risk of metabolic syndrome. Our findings to-date and future areas of research will advance the evidence base that informs dietary guidelines in pregnancy, infancy and childhood, and will be relevant to diverse and high-risk populations of Canada and other high-income countries.
Since the turn of the century, much comparative politics scholarship has examined whether and how income inequality affects the prospects of democratization and, to a lesser extent, whether democracy reduces inequality. What is lacking, however, is a close examination of the extent of income inequality in authoritarian regimes. This article examines the variation in inequality across authoritarian regimes and argues that electoral competition – in conjunction with party ideology and the extent of party institutionalization – helps explain the pattern of inequality under authoritarian rule. I find that electoral authoritarian (EA) regimes – regimes in which multiple parties legally compete in elections – have lower levels of inequality compared to non-EA regimes. I further find that inequality is lower in EA regimes with left-leaning ruling parties and more institutionalized party systems. This analysis highlights the value of exploring the dynamics and contingent effects of electoral competition in authoritarian regimes.
Background: Acute pain is a common presentation in the Emergency Department (ED) and inadequacy in its treatment can lengthen stay. Earlier analgesia use and discharge has been associated with positive patient experiences and improved pain management. Validated ‘fast-track pathways’ to aid physician decision making in analgesic administration is associated with decreased waiting times in renal colic diagnoses. Aim Statement: Our aim was to create an order set, for an approach to patients with acute pain, to reduce median time from point of triage to analgesia. We sought to reduce median time by 15 minutes, for ED patients with renal colic in the three months after implementation as compared to three months before. Measures & Design: We used a literature review and comparison to existing order sets at other EDs to design our draft. We focused our evaluation on patients with renal colic. We underwent multiple revisions based on stakeholder feedback and educated both physician and nursing teams about the order set. The utilization, however, was at physician discretion. We implemented the order set on March 30, 2017. After three months, an electronic retrospective chart review identified patients with a final renal colic diagnosis. For each patient, we captured triage time using electronic records and time to analgesia with the medication cart. Utilization of order sets was confirmed via manual chart audit. Evaluation/Results: A run chart showed worsening times after the intervention. Median time to analgesia in minutes, 3 months prior (n = 90) and post (n = 93) intervention, increased from 228 to 310 minutes, although the range was very large. Chart audits demonstrated a considerably low uptake of the order set with a small gradual increase from 0% to 20% over the 3-month period. Discussion/Impact: There was insufficient uptake of the Acute Pain order set preventing impact on time to analgesia. Changes in occupancy likely contributed to the worsening times. There was an increase in utilization over the 3-month period and could be due to increased awareness. This demonstrates that interventions require more than implementation to be effective. Difficulties in implementation were due to the document not being readily available. We have organized the nursing staff to attach order sets onto charts based on triage assessment and will re-assess with another PDSA cycle after this intervention.
Background: Sepsis is a life-threatening syndrome, and delays to appropriate antibiotic therapy increases mortality. Order sets have shown decrease in time to antibiotics in pneumonia, and in sepsis, the implementation of order sets resulted in more intravenous fluids, appropriate initial antibiotics and lower mortality. Aim Statement: The goal was to create an order set for an approach to septic patients, to improve sepsis management. We sought to improve time from triage to first antibiotics, by 15 minutes, for Emergency Department (ED) patients with sepsis in three months after implementation compared to three months before. Measures & Design: We used a literature review, as well as comparison to existing order sets at other EDs to design our initial order set. We underwent multiple revisions based on stakeholder feedback. We educated physician and nursing teams about the order sets, although use was ultimately at physician discretion. We implemented the order set on April 9, 2017. After three months, an electronic retrospective chart review identified patients with a final sepsis diagnosis admitted to the critical care unit. For each patient, we captured triage time using the electronic record, and time to antibiotics from when the antibiotic was taken out of the medication cart. Finally, utilization of order sets was checked via manual chart audit. Evaluation/Results: A run chart did not demonstrate any shifts or trends suggesting a change after implementation. Median time to antibiotics in minutes, 3 months prior (n = 45) and post (n = 55) intervention, increased from 245 to 340 minutes, although the range was very large. Chart audits demonstrated clinicians were not using the order sets. There was 10% usage for 2 of the months and 0% usage the other month, post-intervention. Disucssion/Impact: There was insufficient uptake of the Sepsis Order Set by the Sunnybrook ED to result in any impact on time to antibiotics. Order sets require more than just implementation to be effective. Difficulties in implementation were due to the document not being readily available to physicians. To mediate, we have organized nursing staff to attach the order set onto charts based on triage assessment and will re-assess with another PDSA cycle after this intervention.
Prenatal and early-life environmental exposures play a key role in the development of atopy and allergic disease. The Family Atherosclerosis Monitoring In earLY life Study is a general, population-based Canadian birth cohort that prospectively evaluated prenatal and early-life traits and their association with atopy and/or allergic disease. The study population included 901 babies, 857 mothers and 530 fathers. Prenatal and postnatal risk factors were evaluated through questionnaires collected during the antenatal period and at 1 year. The end points of atopy and allergic diseases in infants were evaluated through questionnaires and skin prick testing. Key outcomes included atopy (24.5%), food allergy (17.5%), cow’s milk allergy (4.8%), wheezing (18.6%) and eczema (16%). The association between infant antibiotic exposure [odds ratio (OR): 2.04, 95% confidence interval (CI): 1.45–2.88] and increased atopy was noted in the multivariate analysis, whereas prenatal maternal exposure to dogs (OR: 0.60, 95% CI: 0.42–0.84) and acetaminophen (OR: 0.68, 95% CI: 0.51–0.92) was associated with decreased atopy. This population-based birth cohort in Canada demonstrated high rates of atopy, food allergy, wheezing and eczema. Several previously reported and some novel prenatal and postnatal exposures were associated with atopy and allergic diseases at 1 year of age.
Monozygotic (MZ) twins stem from the same single fertilized egg and therefore share all their inherited genetic variation. This is one of the unequivocal facts on which genetic epidemiology and twin studies are based. To what extent this also implies that MZ twins share genotypes in adult tissues is not precisely established, but a common pragmatic assumption is that MZ twins are 100% genetically identical also in adult tissues. During the past decade, this view has been challenged by several reports, with observations of differences in post-zygotic copy number variations (CNVs) between members of the same MZ pair. In this study, we performed a systematic search for differences of CNVs within 38 adult MZ pairs who had been misclassified as dizygotic (DZ) twins by questionnaire-based assessment. Initial scoring by PennCNV suggested a total of 967 CNV discordances. The within-pair correlation in number of CNVs detected was strongly dependent on confidence score filtering and reached a plateau of r = 0.8 when restricting to CNVs detected with confidence score larger than 50. The top-ranked discordances were subsequently selected for validation by quantitative polymerase chain reaction (qPCR), from which one single ~120kb deletion in NRXN1 on chromosome 2 (bp 51017111–51136802) was validated. Despite involving an exon, no sign of cognitive/mental consequences was apparent in the affected twin pair, potentially reflecting limited or lack of expression of the transcripts containing this exon in nerve/brain.
Many studies suggest that strict balanced budget rules can restrain sovereign debt and lower sovereign borrowing costs, even if those rules are never enforced in court. Why might public officials adhere to a rule that is practically never enforced in court? Existing literature points to a legal deterrence logic in which the threat of judicial enforcement deters sovereigns from violating the rules in the first place. By contrast, we argue that balanced budget rules work by coordinating decentralized punishment of sovereigns by bond markets, rather than by posing a credible threat of judicial enforcement. Therefore, the clarity of the focal point provided by the rule, rather than the strength of its judicial enforcement mechanisms, determines its effectiveness. We develop a formal model that captures the logic of our argument, and we assess this model using data on U.S. states. We then consider implications of our argument for the impact of the balanced budget rules recently imposed on eurozone states in the Fiscal Compact Treaty.
The aim of this study was to estimate the amount of childhood hepatitis B virus transmission in children born in the UK, a very low-prevalence country, that is preventable only by universal hepatitis B immunization of infants. Oral fluid specimens were collected from schoolchildren aged 7–11 years in four inner city multi-ethnic areas and tested for the presence of antibody to hepatitis B core antigen (anti-HBc). Those found positive or indeterminate were followed up with testing on serum to confirm their hepatitis B status. The overall prevalence of anti-HBc in children was low [0·26%, 95% confidence interval (CI) 0·14–0·44]. The estimated average annual incidence of hepatitis B was estimated to be 29·26/100 000 children (95% CI 16·00–49·08). The total incidence that is preventable only by a universal infant immunization programme in the UK was estimated to be between 5·00 and 12·49/100 000. The study demonstrates that the extent of horizontal childhood hepatitis B virus transmission is low in children born in the UK and suggests that schools in the UK are an uncommon setting for the transmission of the virus. Targeted hepatitis B testing and immunization of migrants from intermediate- and high-prevalence countries is likely to be a more effective measure to reduce childhood transmission than a universal infant immunization programme.
We investigate the role of precursor thermal rearrangement and surface catalytic reactions in the synthesis of vertically aligned carbon nanotubes (VA-CNTs) by acetylene-based, chemical vapor deposition (CVD) and demonstrate a millimeter-long growth of single-walled CNT (SWNT) without water assistance. A substrate heater was used to create an ascending temperature gradient from gas injection to catalyst substrate. Whereas temperature of catalyst substrates primarily determines their catalytic activity, it is a thermal condition of a gaseous mixture in the CVD chamber that also influence growth yield and structural features of as-grown CNTs. Employing Egloff’s characterization,  we discuss the importance of various gas thermal zones in producing high-quality nanotubes with augmented growth efficiency. We continue to report production of millimeter-long, VA-SWNT having a mean diameter of 1.7 ± 0.7 nm, catalyzed by iron on an alumina support. Important finding is that a million of aspect ratio of SWNT arrays can be produced, without water assistance, via combined action of an ascending temperature gradient toward catalyst substrate and low partial pressures of acetylene carbon feedstock. Our results do not only emphasize the role of precursor thermal rearrangement in CNT synthesis, but also offer a practical route to the modulation of such complex phenomena for an ultrahigh-yield growth of narrow VA-SWNT.
In order to utilise the full potential of carbon nanotubes/nanofibers, it is necessary to be able to synthesize well aligned nanotubes/nanofibres at desired locations on a substrate. This paper examines the preferential growth of aligned carbon nanofibres by PECVD using lithographically patterned catalysts. In the PECVD deposition process, amorphous carbon is deposited together with the nanotubes due to the plasma decomposition of the carbon feed gas, in this case, acetylene. The challenge is to uniformly nucleate nanotubes and reduce the unwanted amorphous carbon on both the patterned and unpatterned areas. An etching gas (ammonia) is thus also incorporated into the PECVD process and by appropriately balancing the acetylene to ammonia ratio, conditions are obtained where no unwanted amorphous carbon is deposited. In this paper, we demonstrate high yield, uniform, ‘clean’ and preferential growth of vertically aligned nanotubes using PECVD.
Plasma Enhanced Chemical Vapour Deposition is an extremely versatile technique for directly growing multiwalled carbon nanotubes onto various substrates. We will demonstrate the deposition of vertically aligned nanotube arrays, sparsely or densely populated nanotube forests, and precisely patterned arrays of nanotubes. The high-aspect ratio nanotubes (~50 nm in diameter and 5 microns long) produced are metallic in nature and direct contact electrical measurements reveal that each nanotube has a current carrying capacity of 107-108 A/cm2, making them excellent candidates as field emission sources. We examined the field emission characteristics of dense nanotube forests as well as sparse nanotube forests and found that the sparse forests had significantly lower turn-on fields and higher emission currents. This is due to a reduction in the field enhancement of the nanotubes due to electric field shielding from adjacent nanotubes in the dense nanotube arrays. We thus fabricated a uniform array of single nanotubes to attempt to overcome these issues and will present the field emission characteristics of this.
We report observations by high resolution electron microscopy of model catalysts produced by impregnating MgO smoke particles with inorganic clusters. With the use of very low beam currents the substrates are of sufficiently low noise that we have been able to image cleanly both single atoms and very small clusters of size l-2nm in sufficient detail to determine their atomic structure. Two types of metal structures are observed: single atoms decorating atomic steps and in a few cases two-dimensional surface rafts, and a population of mainly single crystal with a few multiply twinned particles. The single crystal particles are pseudomorphically epitaxed on the MgO substrates.
II-VI semiconductor alloys have recently received considerable attention for their possible use in double heterostructure (DH) blue laser diodes (LDs).1-4 The purpose of this paper is to present the empirical pseudopotential method within virtual crystal approximation for calculating the band structure of MgZnSSe quaternary alloy. The dependence of band gap energies on alloy composition has shown that MgZnSSe can be a direct or an indirect semiconductor. Electron and hole effective masses are calculated for different composition. Camel's back structure for the X valley conduction band has been found for certain composition range.
Monoclinic ZrO2 and its supported catalysts Co/Ni/ZrO2 for catalytic decomposition of N2O have been studied with FTIR, EDAX, XPS, and the evaluation of activity of the catalysts. It is found that monoclinic ZrO2 alone has the catalytic effect for N2O decomposition although the gas decomposes on Co/Ni/ZrO2 more efficiently. The XPS study shows that only Co exists in the surface region of ZrO2. In evaluation experiments, it is found that when Co/Ni exceeds a threshold concentration, the conversion of N2O is no longer accelerated with the increase of Co/Ni content. The gas decomposition on Co/Ni/ZrO2 can be described as first order with respect to partial pressure of N2O. No nitrogen N(ls) photoelectrons were detected for the catalysts after N2O decomposition. Surface reactions on ZrO2 and Co/Ni/ZrO2, including the behaviour of retained carbon (Cls) and N2O decomposition mechanism, will also be addressed.
We describe the fabrication of self-aligned split gate electrodes on suspended multiwalled carbon nanotube structures. A suspended multiwalled carbon nanotube structure was used as an evaporation mask for the deposition of metal electrodes resulting in the formation of discontinuous wire deposition. The metal deposits on the nanotubes are removed with lift-off due to the poor adhesion of metal to the nanotube surface. Using Al sacrificial layers, it was possible to fabricate self-aligned contact electrodes and control electrodes nanometers from the suspended carbon nanotubes with a single lithography step. It was also shown that the fabrication technique may also be used to form nano-gaped contact electrodes. The technique should prove useful for the fabrication of nano-electromechanical systems.
The goal of the present study was to examine the influence of community environment on the nutritional status (weight-for-age and height-for-age) of children (aged 0–59 months) in Bangladesh. In addition, we tested the association between specific characteristics of community environments and child nutritional status.
The data are from the nationally representative 2004 Bangladesh Demographic and Health Survey.
Respondents were ever-married women (aged 15–49 years) and their children (n 5731), residing in 361 communities. Child nutritional outcomes are physical measurements of weight-for-age and height-for-age in sd units. We considered the following attributes of community environments potentially related to child nutrition: (i) community water and sanitation infrastructure; (ii) availability of community health and education services; (iii) community employment and social participation; and (iv) education level of the community.
Multilevel regression analysis showed that the spatial distribution of maternal and child covariates did not entirely explain the between-community variation in child nutritional status. The education level of the community emerged as the strongest community-level predictor of child height-for-age (highest v. lowest tertile, β = 0·18 (se 0·07)) and weight-for-age (highest v. lowest tertile, β = 0·21 (se 0·06)). In the height-for-age model, community employment and social participation also emerged as being statistically significant (highest v. lowest tertile, β = 0·13 (se = 0·06)).
The community environment influences child nutrition in Bangladesh, and maternal- and child-level covariates may fail to capture the entire influence of communities. Interventions to reduce child undernutrition in developing countries should take into consideration the wider community context.
In this paper we review the use of high pressure techniques to investigate the optical properties of partially ordered GalnP epitaxial layers grown on GaAs substrates. In particular, we demonstrate the ability of high pressure to modify the band alignment at the GalnP/GaAs interface and hence to alter the optical properties of heterostructures fabricated from partially ordered GalnP on GaAs.
High-quality electron sources can be made from individual multi-walled carbon nanotubes. A process was developed allowing the control over 1) the length of the fraction of the nanotube protruding from the support tip, 2) the contact length of the nanotube with the support tip, 3) the diameter of the nanotube. In addition, the cap of the nanotube was closed and the nanotube was cleaned thoroughly. The field emission model successfully describes the electron emission process of these electron sources and the work function is 5.1 eV. The emitters show a highly stable emission, as expected on account of the extremely stable structure of the carbon nanotube.
An alternative method for seeding catalyst nanoparticles for carbon nanotubes and nanowires growth is presented. Ni nanoparticles are formed inside a 450 nm SiO2 film on (100) Si wafers through the implantation of Ni ions at fluences of 7.5×1015 and 1.7×1016 ions cm−2 and post-annealing treatment at 700, 900 and 1100 °C. After exposed to the surface by HF dip etching, the Ni nanoparticles are used as catalyst for the growth of vertically aligned carbon nanotubes by direct current plasma enhanced chemical vapor deposition.