43 research outputs found
Case study on drivers of stormwater user fees in 3 Massachusetts communities
No full textThesis: M.C.P., Massachusetts Institute of Technology, Department of Urban Studies and Planning, 2016.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Cataloged from student-submitted PDF version of thesis.Includes bibliographical references (pages 66-71).Urban stormwater is a major source of pollution in U.S. water bodies. Addressing the problem of stormwater pollution at the municipal level can be expensive, from infrastructure maintenance to implementing regulatory best practices. These needs have put pressure on municipalities to look for a stable source of revenue that extends beyond general tax appropriations for public works projects. In this context, stormwater user fees have remained a hotly debated topic in local budget discussions and national forums about stormwater management. In comparison to the rest of the country, the adoption of fees in Massachusetts communities is plagued by low uptake. This thesis aims to understand the surprisingly small proliferation and early adaptation of stormwater user fees in Massachusetts by identifying the local drivers of fee adoption as an alternative to using local tax income in three communities: Chicopee, Fall River and Northampton. Through a descriptive case study approach using qualitative interviews and publicly available data, the research underscores four key drivers apparent in local fee adoption: financial pressure, local history, governance arrangements of budgets, and cost equity. Ultimately, communities face numerous tradeoffs that affect the momentum and intricacy of the fee adoption process. Lessons learned about the local drivers of stormwater user fees in these three cases are specifically applicable to the Massachusetts context, but can serve as a guide for other New England municipalities considering new fees.by Anisha Anantapadmanabhan.M.C.P
The Romanticization of Mental Illness and Substance Abuse in Young Adult Media
No full textabstract: The following creative project defends that, whether intentionally or not, mental illness and substance abuse are inevitably romanticized in young adult media and discusses the dangers of this romanticization. This project is divided into three parts. The first part consists of psychological evaluations of the main characters of two popular, contemporary forms of young adult media, Catcher in the Rye by J.D Salinger and Euphoria by Sam Levinson. These evaluations use textual evidence and the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) to determine what symptoms of psychopathology the characters appear to display. The second part consists of a self-written short story that is meant to accurately depict the life of a young adult struggling with mental illness and substance abuse. This story contains various aesthetic techniques borrowed from the two young adult media forms. The final part consists of an aesthetic statement which discusses in depth the aesthetic techniques employed within the short story, Quicksand by Anisha Mehra. (abstract
associated sarcomas and pleuropulmonary blastoma: Histopathologic features guide diagnosis in the LMIC setting
No full textExtrapulmonary DICER1-associated sarcomas (DS) can harbor morphological features overlapping with pleuropulmonary blastoma. We report 3 children with intracranial and genital tract sarcomas, suspected to have DS based on a heterogeneous yet defining combination of spindle-cell sarcomatous and blastemal morphology, with rhabdomyomatous differentiation. Foci of immature cartilage at diagnosis (n=2/3) and increased neuroepithelial differentiation at recurrence (n=1) were noted. Morphological suspicion prompted somatic testing at reference centers, confirming likely biallelic, loss-of-function and ‘hotspot’ missense DICER1 variants in all 3 tumors. This can serve as a model for this diagnosis in resource-limited settings and has implications for germline testing, surveillance, and tumor management
IDENTIFYING NEW COMPOUNDS CAPABLE OF INDUCING MODEL PHAGES
No full textMcMaster University MASTER OF SCIENCE (2020) Hamilton, Ontario
(Department of Biochemistry and Biomedical Sciences)
TITLE: Identifying new compounds capable of inducing model phages
AUTHOR: Anisha Nandy
SUPERVISOR: Dr. Alexander P. Hynes
NUMBER OF PAGES: xi, 80Prophages are the genomes of bacteriophages (phages, bacterial
viruses) that integrate into the chromosome of their host upon infection, lying dormant until conditions favour their reactivation. A cell harbouring a
prophage is called a lysogen, as, upon exposure to certain signals, the
prophage will initiate a replicative cycle ending in lysis of the host bacterium
and release of phages. This process is known as induction. Canonically,
induction occurs through activation of the bacterial SOS-response, a DNA repair cascade initiated by detection of DNA damage. Studies of prophage
induction have almost exclusively relied on challenges with compounds that
result in the initiation of the host SOS response.
Recent studies have identified some signals that affect prophage
induction independently of the SOS response, but these approaches have not
been systematic. To identify non-canonical triggers of prophage induction, I
screened 3,936 compounds against two model lysogens. The first, carrying
phage HK97, is a model for induction. The second, carrying phage Mu—a
prophage thought to be uninducible—serves as a control. Any compound
which inhibited bacterial growth in only our HK97 lysogen was considered to
have resulted in a phage-mediated response. The 171 compounds identified in this screen were then used to re-challenge the lysogen at a range of
concentrations and monitor the resulting release of free phages associated
with induction. Increases in phage counts were seen for 86 compounds. While 38 of these were known SOS activators, 49 were novel, ‘non-canonical’ inducers. Unexpectedly, the screening also revealed seven unique chemical inducers for the supposedly un-inducible model prophage, Mu.
The 56 new phage-inducers identified by this work include compounds
likely to be driving phage induction through non-canonical pathways. As
prophages are thought to respond to bacterial stress, these may reflect stressors acting through new mechanisms. Using these compounds as tools opens up an avenue to probe other stress pathways in bacteria, and, as evidenced by induction of Mu, potentially help discover new phages that don’t respond to canonical inducers.ThesisMaster of Science (MSc)Bacterial viruses (phages) can lie dormant as prophages in their host
bacterium until a signal triggers their activation, production of viruses, and
rapid killing of the host. This switch from dormant prophage to active phage called induction. Almost all molecules that result in prophage inductions
belong to a limited set of compounds which elicit a specific stress response in
bacteria.
Screening 3936 compounds for their ability to inhibit the growth of
bacteria carrying known prophages resulted in the identification of a small
subset associated with increased phage production. For one Escherichia coli
prophage—HK97, a model of induction—we found 49 compounds not
previously known as inducers. For another model prophage—Mu, a prophage
thought to be chemically uninducible—we identified seven such compounds.
These compounds will serve as tools to determine what signals prophages can respond to, and potentially identify new stress pathways of
interest in bacteria
Optimization of the Lung Biopsy Procedure: A Primer
No full textImage-guided lung biopsy plays a very important role in the diagnosis and management of lung lesions. As a diagnostic tool, it demands a high diagnostic yield and a low complication rate. It is imperative to balance the diagnostic yield and patient safety during lung biopsies. The aim of this article is to review the standard practice guidelines of lung biopsy, to describe the techniques used to minimize the complications associated with lung biopsy, and to describe the management of complications
Endovascular Stenting for Malignant Obstruction of Superior Vena Cava: A Single-Center Experience Using the Body Floss Technique
No full textPurpose Endovascular stenting is the treatment of choice for malignant obstruction of the superior vena cava (SVC) when rapid symptomatic relief is desired. Body floss technique is not routinely used during SVC stenting but has few advantages over single-access technique. We report our experience with stenting for malignant obstruction of the SVC using the body floss technique.
Materials and Methods Between March 2015 and March 2020, 25 patients (20 men, 5 women; median age, 65 years) with malignant SVC obstruction underwent endovascular stenting of the SVC. We retrospectively evaluated these patients for clinical and technical success rates, complications, recurrence-free survival, and overall survival.
Results Stent placement was successful in 24/25 patients (technical success: 96%). Clinical success was achieved in 23/25 (92%) patients. A mortality rate of 4% (1/25) was noted due to SVC rupture. Partial stent migration was noted in two patients (8%) and was treated by placing an additional overlapping stent. Incidental early stent thrombosis was seen in two patients within 8 hours of stent placement, but these patients showed symptom relief with anticoagulation. Follow-up imaging confirmed stent patency in all patients. Late stent occlusion due to tumor progression was seen in one patient. The primary patency rate was 88% (22/25). Overall median survival of 133 days was observed (range: 1–847 days).
Conclusion Endovascular stenting of the SVC for malignant obstruction using the body floss technique is associated with high technical and clinical success, and low rate of complications
Catheter Lock Anchor Technique for Placement of Retrogradely Tunneled Implantable Ports
No full textPurpose Groshong valved catheters require retrograde tunneling and a port chamber needs to be attached to the catheter after trimming. During this process, working space constraints are generally faced by operators. We describe a novel technique to improve the comfort of the operator while working in a constrained space.
Materials and Methods The port catheter with the distal valve is retrogradely tunneled and trimmed. Thread from absorbable surgical suture is used to anchor the catheter lock. Anchored catheter lock is comfortably pushed over the catheter into the subcutaneous tunnel without it being migrated proximally. Once the port chamber is attached to the catheter, the catheter lock is retrieved back and moved to the locking position. We retrospectively analyzed implantable ports for smoothness of curves and outcomes in terms of catheter days.
Results Technical success was achieved in all patients. There were no periprocedural complications. Clinical success was achieved in 27/29 cases. Early port removal was done due to infection in one patient and for nonhealing of the wound in one patient.
Conclusion The catheter lock anchor is a safe and useful technique for the placement of valved ports. A satisfactory catheter-nut angle can be achieved with this technique
An Efficient Text Classification Scheme Using Clustering
No full textAbstractText classification method that uses efficient similarity measures to achieve better performance is being proposed in this paper. Semi-supervised clustering is used as a complementary step to text classification and is used to identify the components in text collection. Clustering makes use of labeled texts to capture silhouettes of text clusters and unlabeled texts to adapt its centroids. The category of each text cluster is labeled by the label of texts in it. Thus here the text clustering is used to generate the classification model for the next text classification step. When a new unlabeled text is incoming, measure its similarity with the centroids of the text clusters and give its label with that of the nearest text cluster. The similarity is calculated using different similarity measures. Results and evaluations are summarized and it is found that the system provides better accuracy when a Similarity Measure for Text Processing (SMTP) used for the distance calculation
