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The plasma channel formation in the focus of a knife-like nanosecond laser pulse irradiating a gas target is studied theoretically, and in gas-dynamics computer simulations. The distribution of the electromagnetic field in the focus region, obtained analytically, is used to calculate the energy deposition in the plasma, which then is implemented in the magnetohydrodynamic computer code. The modelling of the channel evolution shows that the plasma profile, which can guide the laser pulse, is formed by the tightly focused short knife-like lasers. The results of the simulations show that a proper choice of the convergence angle of a knife-like laser beam (determined by the focal length of the last cylindrical lens), and laser pulse duration may provide a sufficient degree of azimuthal symmetry of the formed plasma channel.
OBJECTIVES/GOALS: Guided by the health belief model and social identity theory, we aim to identify socio-cultural and psychological factors that influence rural tobacco users a) participation in research and b) quitting tobacco use. We also explore how citizen scientists are perceived as disseminators of messages. METHODS/STUDY POPULATION: In Phase I of this multi-stage project, we are conducting in-depth interviews with approximately 30 tobacco users. Interviews are on-going, and have been conducted with 16 participants thus far from four rural counties in Florida. The interview consists of semi-structured questions and multiple validated questionnaires. Specifically, we ask a series of questions about participants’ barriers to participating in research, tobacco use history, and internet use and message preferences. Additionally, we include questionnaires on participants’ substance use, nicotine dependence, motivation to quit, and willingness to participate in research studies. RESULTS/ANTICIPATED RESULTS: Initial findings suggest that rural tobacco users have an overall positive perception of research, and many choose to participate in research for altruistic reasons (i.e. they want to help others). Further, participants noted described feeling stigmatized due to their tobacco use. Although most began smoking to fit in with their community, many now feel on the outs. Participants also reported logistical barriers to participating in research, including lack of transportation. DISCUSSION/SIGNIFICANCE OF IMPACT: Findings can inform the development of recruitment materials to resonate with rural adults, including by emphasizing the collective potential to help by participating. This interdisciplinary highlights areas for collaboration to enhance the reach of health education and public health messages.
In chronic disease there is a trend towards looking at patients perspective and experience to improve health-care. A recent audit conducted with COPD-patients demonstrated a need to receive information about their disease and the need to be addressed as an individual, not as a disease. (Powell et al, Breathe, sept 2013)
To examine if addressing these 2 needs can change patients disease experience, we set up a study with 15 COPD-patients included in a Pulmonary Rehabilitation Program. Ten subjects had already undergone functional lung imaging in the past, using CT thorax images. These 10 patients received some personalized information about their disease, confronting them with their own lung images during each of 4 visits, spread over a period of 6 months. On each visit they filled out self-reporting questionnaires about symptoms and Healt-Related Quality Of Life. The other 5 patients filled out the questionnaires without receiving this information.
Patients receiving this personalized education, showed an improvement in the COPD Assessment Test (CAT) (p=0.023)(which measures the impact of COPD symptoms on daily life), whereas controls did not.
When the two groups were taken together, we can see symptom scores (as assessed by the Saint-George Respiratory Questionnaire and the Severe Respiratory Insufficiency Questionnaire) correlate with self-efficacy (Pulmonary Rehabilitation Adepted Index of Self-Efficacy). Symptom reporting seems to correlate with self-efficacy, which is a measure for self-confidence in disease.
This study shows how patient education using personalized feedback can improve patient reported symptoms, possibly by improving self-efficacy.
Experimental studies support a neurotrophic hypothesis of major depressive disorder (MDD). The aim of this study was to determine the effect of Val66Met brain derived neurotrophic factor (BDNF) polymorphism on the white matter fibre tracts connecting hippocampus and amygdala with the prefrontal lobe in a sample of patients with MDD and healthy controls.
Thirty seven patients with MDD and 42 healthy volunteers were recruited. Diffusion tensor imaging (DTI) data with 61 diffusion directions were obtained with MRI 3 Tesla scanner. Deterministic tractography was applied with ExploreDTI and Val66Met BDNF SNP (rs6265) was genotyped. Fibre tracts connecting the hippocampus and amygdala with the prefrontal lobe, namely uncinate fasciculus, fornix and cingulum were analysed.
A significant interaction was found in the uncinate fasciculus (UF) between BDNF alleles and diagnosis. Patients carrying the BDNF met-allele had smaller fractional anisotropy (FA) in the UF compared to those patients homozygous for valallele and compared to healthy subjects carrying the met-allele. A significant 3-way interaction was detected between region of the cingulum (dorsal, rostral and parahippocampal regions), brain hemisphere and BDNF genotype. Larger FA was detectable in the left rostral cingulum for met-allele carriers when compared to val/val alelle carriers.
We provide evidence for the importance of the neurotrophic involvement in limbic and prefrontal connections. The met-allele of the BDNF polymorphism seems to render subjects more vulnerable for dysfunctions associated with the UF, a tract known to be related to negative emotional-cognitive processing bias, declarative memory problems, and autonoetic self awareness.
Laparoscopic Roux-en-Y gastric bypass (RYGB) is considered the ‘gold standard’ for surgical treatment of morbid obesity. It is hypothesised that reducing the length of the common limb positively affects the magnitude and preservation of weight loss but may also impose a risk of malnutrition. The aim of this study was to compare patients’ nutrient and vitamin deficiencies in standard RYGB with a very long Roux limb RYGB (VLRL-RYGB). This study was part of the multicentre randomised controlled trial (Dutch Common Channel Trial), including 444 patients undergoing an RYGB or a VLRL-RYGB. Laboratory results, use of multivitamin supplements and reoperations were collected at baseline and 1 year postoperative. Primary outcome measure was nutrient deficiency after 1 year postoperative. Secondary outcome measure was the reoperation rate due to malabsorption. In total, 227 patients underwent RYGB and 196 patients underwent VLRL-RYGB. Most common deficiencies at 1 year postoperative were ferritin (17·2–18·2 %), Fe (23·4–35·6 %), K (7·4–15·2 %), vitamin B12 (9·0–9·9 %) and vitamin D (22·7–34·5 %). Patients undergoing VLRL-RYGB had slightly but significantly lower levels of Ca, Fe and vitamin D compared with those undergoing RYGB at 1 year postoperative, but significantly higher levels of folic acid and Na. Reoperation rates due to malabsorption were not significantly different between RYGB (2/227, 0·9 %) and VLRL-RYGB (7/196, 3·6 %) (P = 0·088). We concluded that patients undergoing VLRL-RYGB had significantly lower levels of Ca, Fe and vitamin D compared with those undergoing RYGB at 1 year postoperative, but higher levels of folic acid and Na. Reoperation rates did not differ. Close monitoring on nutrient deficiencies should be performed in patients undergoing VLRL-RYGB.
Little is known about designing research recruitment campaigns that connect with underserved, geographically isolated rural populations. A theoretically informed process is needed to assist research teams and practitioners in their evaluation of Facebook’s feasibility as a recruitment tool and development of online materials for recruiting rural adults into healthcare delivery intervention development studies.
We drew from research and theory in communication and incorporated process analysis techniques to develop replicable procedures for designing and evaluating Facebook campaigns for rural recruitment. We describe our process and illustrate using two case studies.
Campaigns received approximately 1000 link clicks from the target rural demographic and successfully enrolled participants using Facebook as a primary method of recruitment. The rural tobacco intervention development study received a total of 477 link clicks, cost only $155.80, and enrolled three (23%) of its 13 participants from Facebook. The rural mental health intervention development study received a total of 518 link clicks, cost only $233.28, and enrolled 178 participants.
Our process yielded two successful recruitment campaigns. Facebook was an affordable and efficacious strategy for enrolling adults in behavioral research studies on tobacco and mental health. Future work should apply these theoretical techniques to additional study topics and evaluate specific message features associated with recruitment.
Since their widespread adoption in the nineteenth century, censuses have played both bureaucratic and ideological roles, as the classification of the population according to social and cultural characteristics facilitated the development of the administrative infrastructure required by emergent nation-states and the definition of national and group identity categories officialized particular ways of understanding difference. This chapter critically analyzes the questions about language asked by Statistics Canada and the US Census Bureau. I examine the relationship of language data to various policies in the two countries, as well as the ways that those policies, and specific ways of asking about language, reflect and reproduce particular ideologies of language. In addition to revealing differing perspectives on individual and societal multilingualism, this analysis demonstrates that census language statistics do not simply serve as "facts" undergirding policy, but instead produce particular representations of linguistic diversity and, thus, constitute official discourses on multilingualism.
OBJECTIVES/SPECIFIC AIMS: Our overarching theoretical framework is the health belief model (HBM). Guided by HBM, we aim to identify rural adults’ perceived barriers and motivations to participating in research. Specifically, our research questions are listed below. RQ1: What socio-cultural factors influence rural tobacco users’ intentions to a) participate in research studies and b) undertake tobacco cessation? RQ2: What bio-psychological and behavioral factors influence rural tobacco users’ intentions to a) participate in research studies and b) undertake tobacco cessation? RQ3: How do rural tobacco users perceive citizen scientists as disseminators of a) tobacco cessation and b) recruitment messages? METHODS/STUDY POPULATION: In Phase I of this multi-stage project, we are conducting in-depth interviews with approximately 30 tobacco users in rural Florida. The interview consists of semi-structured questions and multiple validated questionnaires. Specifically, we ask a series of questions about participants’ barriers to participating in research. Additionally, we include questionnaires on participants’ tobacco use history, nicotine dependence, motivation to quit, and willingness to participate in research studies. RESULTS/ANTICIPATED RESULTS: This study consists of two main phases. Data collection for Phase 1 of the study is ongoing, and we will discuss these recent findings. We anticipate data collection and data analysis to be finalized by May, 2019. Beginning in August 2019 through August 2020, we will focus on Phase II, which entails designing and implementing an intervention to increase rural tobacco users’ willingness to participate in research. Given existing literature on other underrepresented groups in research, we anticipate that rural tobacco users will express that logistical barriers, such as transportation and time, prevent them from participating in research. Additionally, we anticipate these individuals may have socio-cultural barriers to participating in research, including distrust in the medical system and apprehension over discipline-specific terminology. DISCUSSION/SIGNIFICANCE OF IMPACT: The results of this formative research will be critical to our development of a targeted intervention to increase rural tobacco users’ participation in research. Additionally, our interdisciplinary and community-based approach in this study acknowledges the importance of involving the target population in the research process, which is in line with NIH’s updated model of translational research. We will discuss the process of collaborating with extension agents in rural counties in Florida to reach underrepresented communities.
Although repeatedly associated with white matter microstructural alterations, bipolar disorder (BD) has been relatively unexplored using complex network analysis. This method combines structural and diffusion magnetic resonance imaging (MRI) to model the brain as a network and evaluate its topological properties. A group of highly interconnected high-density structures, termed the ‘rich-club’, represents an important network for integration of brain functioning. This study aimed to assess structural and rich-club connectivity properties in BD through graph theory analyses.
We obtained structural and diffusion MRI scans from 42 euthymic patients with BD type I and 43 age- and gender-matched healthy volunteers. Weighted fractional anisotropy connections mapped between cortical and subcortical structures defined the neuroanatomical networks. Next, we examined between-group differences in features of graph properties and sub-networks.
Patients exhibited significantly reduced clustering coefficient and global efficiency, compared with controls globally and regionally in frontal and occipital regions. Additionally, patients displayed weaker sub-network connectivity in distributed regions. Rich-club analysis revealed subtly reduced density in patients, which did not withstand multiple comparison correction. However, hub identification in most participants indicated differentially affected rich-club membership in the BD group, with two hubs absent when compared with controls, namely the superior frontal gyrus and thalamus.
This graph theory analysis presents a thorough investigation of topological features of connectivity in euthymic BD. Abnormalities of global and local measures and network components provide further neuroanatomically specific evidence for distributed dysconnectivity as a trait feature of BD.
Despite the frequent references to identity within the field of heritage language education, it is only in the past decade or so that scholars have begun to conduct empirical research on this topic. This article examines recent research on identity and heritage language education in the United States. The article begins with a discussion of the simultaneous development of heritage language education as a field and growth of interest in identity and language learning, followed by a critical examination of the terms “heritage language” and “heritage language education,” as well as of “heritage language learner” as an identity category. Next is a review of empirical studies conducted within the past 5 years, including survey-based research that considered identity in the exploration of students’ reasons for heritage language study, in addition to qualitative and ethnographic research that focused specifically on heritage language learners’ sense of themselves and their relationship to the heritage language, as well as on the ways that heritage language learner identities are constructed, indexed, and negotiated in classroom settings. The next section looks at recent research on pedagogical approaches designed to engage heritage language learners in critical considerations of language and identity. The article concludes with suggestions for future research.
White matter (WM) abnormalities are proposed as potential endophenotypic markers of bipolar disorder (BD). In a diffusion tensor imaging (DTI) voxel-based analysis (VBA) study of families multiply affected with BD, we previously reported that widespread abnormalities of fractional anisotropy (FA) are associated with both BD and genetic liability for illness. In the present study, we further investigated the endophenotypic potential of WM abnormalities by applying DTI tractography to specifically investigate tracts implicated in the pathophysiology of BD.
Diffusion magnetic resonance imaging (MRI) data were acquired from 19 patients with BD type I from multiply affected families, 21 of their unaffected first-degree relatives and 18 healthy volunteers. DTI tractography was used to identify the cingulum, uncinate fasciculus (UF), arcuate portion of the superior longitudinal fasciculus (SLF), inferior longitudinal fasciculus (ILF), corpus callosum, and the anterior limb of the internal capsule (ALIC). Regression analyses were conducted to investigate the effect of participant group and genetic liability on FA and radial diffusivity (RD) in each tract.
We detected a significant effect of group on both FA and RD in the cingulum, SLF, callosal splenium and ILF driven by reduced FA and increased RD in patients compared to controls and relatives. Increasing genetic liability was associated with decreased FA and increased RD in the UF, and decreased FA in the SLF, among patients.
WM microstructural abnormalities in limbic, temporal and callosal pathways represent microstructural abnormalities associated with BD whereas alterations in the SLF and UF may represent potential markers of endophenotypic risk.
This chapter presents an overview on the current recommendations and guidelines that may be implemented to improve the management of planned and unplanned urgent high-risk obstetric patients and prevent fatal outcomes for both mothers and their babies. Reviewing morbidity and mortality data over the 10 years from 2000 reveals an increase in the proportion of indirect causes of maternal deaths and demonstrates that many of the case-fatalities were women who did not receive pre-pregnancy counseling or any specific medical management. The chapter discusses two examples of multidisciplinary care planning: for women who have placenta previa with acreta and have had a previous cesarean section and for women with a serious comorbidity. The goal of rapid response teams (RRTs) is to bring critical expertise and equipment to the patient without delay, in a timely manner, and to provide a solution to the problem in a standardized manner.