Modeling power transmission networks is an important area of research with applications such as v... more Modeling power transmission networks is an important area of research with applications such as vulnerability analysis, study of cascading failures, and location of measurement devices. Graph-theoretic approaches have been widely used to solve these problems, but are subject to several limitations. One of the limitations is the ability to model a heterogeneous system in a consistent manner using the standard graph-theoretic formulation. In this paper, we propose a network-of-networks approach for modeling power transmission networks in order to explicitly incorporate heterogeneity in the model. This model distinguishes between different components of the network that operate at different voltage ratings, and also captures the intra and inter-network connectivity patterns. By building the graph in this fashion we present a novel, and fundamentally different, perspective of power transmission networks. Consequently, this novel approach will have a significant impact on the graph-theoretic modeling of power grids that we believe will lead to a better understanding of transmission networks.
Language users can create moral geographies, in which values are mapped in space, by indexically ... more Language users can create moral geographies, in which values are mapped in space, by indexically linking values and spatial referents. One understudied aspect of linguistic practice in this domain is the role of toponyms in constructing a moral geography. This investigation illustrates how sociolinguistic variants of a toponym can be used to construct a moral geography. I take as a case study sociolinguistic variation in the US state name Missouri, which can be produced as Missouree or Missourah. Qualitative analysis of a set of local newspaper columns shows these variants can be used as place names. However, they do not distinguish regions of physical space. Rather, the variants label moral spaces by setting each variant on opposing ends of cultural, geographic, and political axes of contrast. Because their primary role is to label moral space, I suggest that toponymic studies should consider the kind of geography that a toponym labels space within. I consider the usage here to be ...
ABSTRACTThis article calls attention to the saliency of secondary education within the community ... more ABSTRACTThis article calls attention to the saliency of secondary education within the community and its utility in constructing social categories, in order to consider how it affects linguistic variation. Older St. Louisans draw on secondary education to construct a divide between those who attended Catholic high schools and those who attended public schools. I show that speakers in a sample of older St. Louisans differ in production of thethoughtvowel based on education type. This effect is weakened in apparent time when we consider a larger sample that includes both older and younger speakers. I draw on Brubaker's (2004) view of groups as events and actions to argue that these categories were indexed only while they had a high degree of groupness, and suggest that social changes that led to diminished groupness between Catholics and Publics also resulted in the loss of a linguistic distinction between the groups. (Education, groups, Northern Cities Shift, Catholicism)*
In this paper, we explore methodological approaches to use and grammaticality of syntactic variab... more In this paper, we explore methodological approaches to use and grammaticality of syntactic variables. We argue that no single method can viably contribute this complete picture in and of itself. Rather, multiple methodologies are required to obtain a holistic understanding of a syntactic variable. We illustrate this through a case study of wh-all questions, wh-questions in which the presence of all indicates that a plural answer is sought, in North American English (AmE). We take a three-pronged approach to the variable: a corpus study, a Twitter study, and a grammaticality judgment survey. This approach allows us to gather and analyze different kinds of data to create a complete picture of the variable in question. We show that wh-all questions are widespread in AmE, yet subject to regional variation, and that their use is restricted to informal registers. Such findings are a result of the combination of methodologies; no single methodology could yield every result we report. The a...
The development of an autologous tissue engineered vascular graft (TEVG) holds great promise for ... more The development of an autologous tissue engineered vascular graft (TEVG) holds great promise for improving outcomes in congenital heart surgery. The first clinical trial showed that this approach is safe and effective but that the primary mode of failure is stenosis. In a C57BL/6 mouse model of unseeded TEVGs implanted as inferior vena cava interposition grafts, neovessels form in 2 weeks and patent grafts show endothelial and smooth muscle cell (SMC) layers, but occluded grafts show accumulation of SMCs. This suggests stenosis results from abnormal SMC in-growth in the neointima. Studies on fibrosis have shown that resident endothelial cells (EC) contribute to fibroblast accumulation through endothelial-mesenchymal transition (EMT). We utilized transgenic EC lineage-tracing mouse models to track the occurrence of EMT in our TEVG and found an increased percentage of cells co-expressing LacZ and smooth muscle actin in occluded grafts, suggesting that EMT contributes to occlusion in o...
One of the biggest problems for variationist approaches to syntactic variation is the question of... more One of the biggest problems for variationist approaches to syntactic variation is the question of where such variation occurs in the grammar, and what type of variation is allowed. Kroch (1994) suggests that syntactic variables are a result of Competing Grammars, in which grammars that derive differing surface outputs are in competition and selected by the speaker. In this paper, I observe an implicit prediction of the Competing Grammars viewpoint as typically described: material above the variable cannot condition variation. I test this prediction in a variationist study of embedded passives (the ëneeds washedí construction) in Pittsburghese, and show that material above the variable does condition variation. This finding suggests that a look-ahead problem arises if a grammar in competition is selected prior to derivation of the variable. To solve this, I propose that both grammars are initially derived, and that the derivation transferred to LF and PF is chosen in Spell-Out from t...
This study highlights the importance of urban/suburban contact to linguistic variation. I explore... more This study highlights the importance of urban/suburban contact to linguistic variation. I explore two case studies of intra-metropolitan contact and their effect on variation in the English of Greater St. Louis, USA. Data comes from 14 white women born 1971-1991 from outer-ring suburbs in St. Charles County who differ in their length of commute, and twelve white women born 1935-1952 from the City of St. Louis who differ in whether they moved to suburbs in adulthood. The results suggest that in contact situations, the city and suburb accommodate to one another: commuting towards the city yields more ʻcity-likeʼ speech, while moving away from the city yields more ʻsuburb-likeʼ speech. However, identity mediates these contact situations through stylized social practice.
Disclaimer 2020: The EACTS/AEPC Guidelines represent the views of the EACTS and the AEPC and were... more Disclaimer 2020: The EACTS/AEPC Guidelines represent the views of the EACTS and the AEPC and were produced after careful consideration of the scientific and medical knowledge and the evidence available at the time of their dating. The EACTS and AEPC are not responsible in the event of any contradiction, discrepancy and/or ambiguity between the EACTS and AEPC Guidelines and any other official recommendations or guidelines issued by the relevant public health authorities, in particular in relation to good use of healthcare or therapeutic strategies. Health professionals are encouraged to take the EACTS and AEPC Guidelines fully into account when exercising their clinical judgement as well as in the determination and the implementation of preventive, diagnostic or therapeutic medical strategies; however, the EACTS and AEPC Guidelines do not, in any way whatsoever, override the individual responsibility of health professionals to make appropriate and accurate decisions in consideration of each patient's health condition and, where appropriate and/or necessary, in consultation with that patient and the patient's care provider. Nor do the EACTS and AEPC Guidelines exempt health professionals from giving full and careful consideration to the relevant official, updated recommendations or guidelines issued by the competent public health authorities, in order to manage each patient's case in light of the scientifically accepted data pursuant to their respective ethical and professional obligations. It is also the health professional's responsibility to verify the applicable rules and regulations relating to drugs and medical devices at the time of prescription.
The distances between urban and suburban spaces, while small in Euclidean terms, have a rather la... more The distances between urban and suburban spaces, while small in Euclidean terms, have a rather large social reality. This paper calls attention to two reasons for this—suburban development and metropolitan fragmentation—and situates these phenomena within the context of sociological and historical thought about metropolitan areas. I test their role in linguistic variation through a case study of three Northern Cities Shift features (raised trap, fronted lot, and lowered thought) in English of the St. Louis metropolitan area. I show that these features diffused throughout the region in three different ways. Additionally, phonological conditioning of lot-fronting differs between urban and suburban speakers, and retreat from urban dialect features is led in the suburbs. These findings highlight the need to consider the geography of metropolitan areas more deeply in studies of language variation and change in metropolitan areas, as similarity across a metropolitan area should not be ass...
Proceedings of the Linguistic Society of America, 2019
The English ish-construction, in which ish follows an utterance to indicate hedging, is multimoda... more The English ish-construction, in which ish follows an utterance to indicate hedging, is multimodal. It has a prosodic component (a pause between the utterance and ish), and, as observed in this paper, it is often accompanied by a co-speech gesture such as a shrug. Data from a perception study suggests that unlike prosody, gesture is not a grammatical component of the ish-construction. However, gesture does play a significant role in conveying affect to listeners. I suggest that this use of gesture is a not-at-issue contribution to the utterance, and call for further work uniting the semantics/pragmatics and sociolinguistics of gesture.
JAMA otolaryngology-- head & neck surgery, Jan 11, 2018
Proton pump inhibitors (PPI) are commonly prescribed to children with oropharyngeal dysphagia and... more Proton pump inhibitors (PPI) are commonly prescribed to children with oropharyngeal dysphagia and resultant aspiration based on the assumption that these patients are at greater risk for reflux-related lung disease. There is little data to support this approach and the potential risk for increased infections in children treated with PPI may outweigh any potential benefit. The aim of this study was to determine if there is an association between hospitalization risk in pediatric patients with oropharyngeal dysphagia and treatment with PPI. We performed a retrospective cohort study to compare the frequency and length of hospitalizations for children who had abnormal results on videofluoroscopic swallow studies that were performed between January 1, 2015, and December 31, 2015, and who were or were not treated with PPI, with follow-up through December 31, 2016. Records were reviewed for children who presented for care at Boston Children's Hospital, a tertiary referral center. Parti...
To determine if any presenting symptoms are associated with aspiration risk, and to evaluate the ... more To determine if any presenting symptoms are associated with aspiration risk, and to evaluate the reliability of clinical feeding evaluation (CFE) in diagnosing aspiration compared with videofluoroscopic swallow study (VFSS). We retrospectively reviewed records of children under 2 years of age who had evaluation for oropharyngeal dysphagia by CFE and VFSS at Boston Children's Hospital and compared presenting symptoms, symptom timing, and CFE and VFSS results. We investigated the relationship between symptom presence and aspiration using the Fisher exact test and stepwise logistic regression with adjustment for comorbidities. CFE and VFSS results were compared using the McNemar test. Intervals from CFE to VFSS were compared using the Student t test. A total of 412 subjects with mean (±SD) age 8.9 ± 6.9 months were evaluated. No symptom, including timing relative to meals, predicted aspiration on VFSS. This lack of association between symptoms and VFSS results persisted even in the...
Proceedings of the Annual Meetings on Phonology, 2016
The production of the lax vowel /æ/ is widely studied as a sociolinguistic variable in American E... more The production of the lax vowel /æ/ is widely studied as a sociolinguistic variable in American English, as several dialects differ in the allophonic distribution of lax and tense variants of the vowel. Using a forced-choice well-formedness judgment task, this paper tests whether the /æ/ used by Northern Cities Shift (NCS) speakers, which is described as a raised and tensed [ɛə] in all environments, is still represented as a lax vowel in speakers’ grammars. Participants who were native speakers of California English, which only tenses preceding nasals, and NCS English, which tenses everywhere, were asked to choose which of a pair of nonce words, constructed to include a lax-only environment /Vsk, Vsp/, as in gasp, risk, sounds more like a possible English word. California English speakers significantly prefer frames containing lax vowels, including [æ], over those containing tense vowels. NCS speakers respond in the same way: they favor [ɛə] in trials like [bɛəsp] vs. [bisp] just as...
Laboratory investigation; a journal of technical methods and pathology, Jun 7, 2016
MicroRNA expression in formalin-fixed paraffin-embedded tissue (FFPE) or plasma may add value for... more MicroRNA expression in formalin-fixed paraffin-embedded tissue (FFPE) or plasma may add value for cancer management. The GastroGenus miR Panel was developed to measure 55 cancer-specific human microRNAs, Epstein-Barr virus (EBV)-encoded microRNAs, and controls. This Q-rtPCR panel was applied to 100 FFPEs enriched for adenocarcinoma or adjacent non-malignant mucosa, and to plasma of 31 patients. In FFPE, microRNAs upregulated in malignant versus adjacent benign gastric mucosa were hsa-miR-21, -155, -196a, -196b, -185, and -let-7i. Hsa-miR-18a, 34a, 187, -200a, -423-3p, -484, and -744 were downregulated. Plasma of cancer versus non-cancer controls had upregulated hsa-miR-23a, -103, and -221 and downregulated hsa-miR-378, -346, -486-5p, -200b, -196a, -141, and -484. EBV-infected versus uninfected cancers expressed multiple EBV-encoded microRNAs, and concomitant dysregulation of four human microRNAs suggests that viral infection may alter cellular biochemical pathways. Human microRNAs w...
Previous studies have demonstrated the benefits of cell seeding in the construction of tissue-eng... more Previous studies have demonstrated the benefits of cell seeding in the construction of tissue-engineered vascular grafts (TEVG). However, seeding methods are diverse and no method is clearly superior in either promoting seeding efficiency or improving long-term graft function. As we head into an era during which a variety of different TEVG are under investigation in clinical trials around the world, it is important to consider the regulatory issues surrounding the translation of these technologies. In this review, we summarize important advances in the field of vascular tissue engineering, with particular attention on cell-seeding techniques for TEVG development and special emphasis placed on regulatory issues concerning the clinical translation of these various methods.
The Journal of Thoracic and Cardiovascular Surgery, 2012
The development of a living, tissue-engineered vascular graft (TEVG) holds great promise for adva... more The development of a living, tissue-engineered vascular graft (TEVG) holds great promise for advancing the field of cardiovascular surgery. However, the ultimate source and time needed to procure these cells remain problematic. Induced puripotent stem (iPS) cells have recently been developed and have the potential for creating a pluripotent cell line from a patient's own somatic cells. In the present study, we evaluated the use of a sheet created from iPS cell-derived vascular cells as a potential source for the construction of TEVG. Methods: Male mouse iPS cells were differentiated into embryoid bodies using the hanging-drop method. Cell differentiation was confirmed by a decrease in the proportion of SSEA-1-positive cells over time using fluorescence-activated cell sorting. The expression of endothelial cell and smooth muscle cell markers was detected using real-time polymerase chain reaction (PCR). The differentiated iPS cell sheet was made using temperature-responsive dishes and then seeded onto a biodegradable scaffold composed of polyglycolic acid-poly-L-lactide and poly(L-lactide-co-ε-caprolactone) with a diameter of 0.8 mm. These scaffolds were implanted as interposition grafts in the inferior vena cava of female severe combined immunodeficiency/beige mice (n ¼ 15). Graft function was serially monitored using ultrasonography. The grafts were analyzed at 1, 4, and 10 weeks with histologic examination and immunohistochemistry. The behavior of seeded differentiated iPS cells was tracked using Y-chromosome fluorescent in situ hybridization and SRY real-time PCR. Results: All mice survived without thrombosis, aneurysm formation, graft rupture, or calcification. PCR evaluation of iPS cell sheets in vitro demonstrated increased expression of endothelial cell markers. Histologic evaluation of the grafts demonstrated endothelialization with von Willebrand factor and an inner layer with smooth muscle actin-and calponin-positive cells at 10 weeks. The number of seeded differentiated iPS cells was found to decrease over time using real-time PCR (42.2% at 1 week, 10.4% at 4 weeks, 9.8% at 10 weeks). A fraction of the iPS cells were found to be Y-chromosome fluorescent positive at 1 week. No iPS cells were found to co-localize with von Willebrand factor or smooth muscle actin-positive cells at 10 weeks. Conclusions: Differentiated iPS cells offer an alternative cell source for constructing TEVG. Seeded iPS cells exerted a paracrine effect to induce neotissue formation in the acute phase and were reduced in number by apoptosis at later time points. Sheet seeding of our TEVG represents a viable mode of iPS cell delivery over time. (
The results of newborn drug screening have far-reaching impact not only in healthcare, but also i... more The results of newborn drug screening have far-reaching impact not only in healthcare, but also in the legal domain. Therefore, the accuracy of these results cannot be undervalued. When false positive cannabinoid (THC) screening results for this population were suspected at our institution, a multidisciplinary approach was initiated to evaluate the screening process for any pre-analytical or analytical sources of error or interference. Design and methods: Mixtures of drug-free urine with various commercial products and materials that commonly contact newborns in our nursery were prepared and tested using the immunoassay screening methods in our laboratory. Additional commercial products were similarly tested; and when available, individual surfactants common to the interfering products were also evaluated. Results: Addition of Head-to-Toe Baby Wash to drug-free urine produced a dose dependent measureable response in the THC immunoassay. Addition of other commercially available baby soaps gave similar results, and subsequent testing identified specific chemical surfactants that reacted with the THC immunoassay. Conclusion: We have identified commonly used soap and wash products used for newborn and infant care as potential causes of false positive THC screening results. Such results in this population can lead to involvement by social services or false child abuse allegations. Given these consequences, it is important for laboratories and providers to be aware of this potential source for false positive screening results and to consider confirmation before initiating interventions. Most importantly, we demonstrate the need for active involvement in the "total testing process," as sources of error are not confined to the laboratory walls.
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