17 research outputs found
Cities in the Everglades : the implications of compact urban development for regional water storage in Palm Beach County
Thesis (M.C.P.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 2001.Some maps folded.Includes bibliographical references (p. [157]-161).Alternative forms of urban development such as high-density or in-fill development are often promoted for their significant environmental benefits. South Florida presents an excellent testing ground for this assumption, as the region grapples with issues of rapid urbanization and degradation of the Everglades, a unique ecosystem containing the largest freshwater wetlands in the United States. Resolving the competition for water between growing urban populations, the agriculture sector, and the plants and animals of the Everglades is one of the fundamental challenges of Everglades restoration. Hydrologists claim that sufficient water is available for all three if the water is managed properly and sufficient water storage can be found. In recent years, South Florida has adopted compact development as a means of managing its urban growth and curbing the historical patterns of low-density urban sprawl, so that future urban growth is compatible with ecosystem restoration. However the hydrologic benefits of compact development have yet to be quantified and proven. By using Palm Beach County as an example, this study evaluates the impact of compact development on aquifer recharge, which is an important means of storing water for the region. This analysis models the spatial distribution of future urban development under sprawl and compact development scenarios and evaluates potential aquifer recharge under the two development patterns. The results of this analysis indicate that while compact development confers some benefits to water storage, these benefits will pale in light of the growing water needs of the region's burgeoning population. Therefore, while the county should adopt compact development for its benefits, however small, policy makers should not count on this policy alone to ameliorate the negative environmental impacts of future population growth in the region.by Ambika Anand Prokop.M.C.P
Beyond Trophic Factors: Exploiting the Intrinsic Regenerative Properties of Adult Neurons
Injuries and diseases of the peripheral nervous system (PNS) are common but frequently irreversible. It is often but mistakenly assumed that peripheral neuron regeneration is robust without a need to be improved or supported. However, axonal lesions, especially those involving proximal nerves rarely recover fully and injuries generally are complicated by slow and incomplete regeneration. Strategies to enhance the intrinsic growth properties of reluctant adult neurons offer an alternative approach to consider during regeneration. Since axons rarely regrow without an intimately partnered Schwann cell (SC), approaches to enhance SC plasticity carry along benefits to their axon partners. Direct targeting of molecules that inhibit growth cone plasticity can inform important regenerative strategies. A newer approach, a focus of our laboratory, exploits tumor suppressor molecules that normally dampen unconstrained growth. However several are also prominently expressed in stable adult neurons. During regeneration their ongoing expression “brakes” growth, whereas their inhibition and knockdown may enhance regrowth. Examples have included phosphatase and tensin homolog deleted on chromosome ten (PTEN), a tumor suppressor that inhibits PI3K/pAkt signaling, Rb1, the protein involved in retinoblastoma development, and adenomatous polyposis coli (APC), a tumor suppressor that inhibits β-Catenin transcriptional signaling and its translocation to the nucleus. The identification of several new targets to manipulate the plasticity of regenerating adult peripheral neurons is exciting. How they fit with canonical regeneration strategies and their feasibility require additional work. Newer forms of nonviral siRNA delivery may be approaches for molecular manipulation to improve regeneration
Mucormycosis infection associated with global COVID-19 pandemic - an institutional histopathological study
Coronavirus disease 2019 (COVID-19) in the recent times have instilled signs of immunosuppression globally which has further precipitated increasing range of opportunistic infections. Mucormycosis is a distressing opportunistic fungal infection with a high incidence and is the third commonest acute invasive infection following candidiasis and aspergillosis. The aim of the present observational study is to delineate the enigmatic histopathological profile between mucormycosis cases seen prior to pandemic (PPM) and pandemic associated mucormycosis (PAM). Tissue archives of 105 histopathologically diagnosed cases of mucormycosis were included and analysed for demographical details and histopathological parameters like fungal load and localization, granuloma formation, necrosis, inflammatory infiltrate and tissue invasion. 0ut of 105 included cases, 11/105 (10.48%) were reported PPM and 94/105 (89.52%) PAM. Among 94 cases of PAM, 51/94 (54%) cases also showed COVID-19 positivity, while 43/94 (46%) did not. Of all the histological variables, increased fungal load and necrosis were observed in PAM relative to PPM cases. The histopathological variables like fungal load, necrosis, granuloma formation and tissue invasion, could help the clinician in assessing the clinical status at the time of tissue diagnosis and improve the treatment accordingly
Prevalence and type distribution of high-risk Human Papillomavirus (HPV) in breast cancer : a Qatar based study
Human papillomavirus (HPV) has been implicated in the etiology of a variety of human cancers. Studies investigating the presence of high-risk (HR) HPV in breast tissue have generated considerable controversy over its role as a potential risk factor for breast cancer (BC). This is the first investigation reporting the prevalence and type distribution of high-risk HPV infection in breast tissue in the population of Qatar. A prospective comparison blind research study herein reconnoitered the presence of twelve HR-HPV types’ DNA using multiplex PCR by screening a total of 150 fresh breast tissue specimens. Data obtained shows that HR-HPV types were found in 10% of subjects with breast cancer; of which the presence of HPV was confirmed in 4/33 (12.12%) of invasive carcinomas. These findings, the first reported from the population of Qatar, suggest that the selective presence of HPV in breast tissue is likely to be a related factor in the progression of certain cases of breast cancer
HER2-enriched subtype and novel molecular subgroups drive aromatase inhibitor resistance and an increased risk of relapse in early ER+/HER2+ breast cancer
BACKGROUND: Oestrogen receptor positive/ human epidermal growth factor receptor positive (ER+/HER2+) breast cancers (BCs) are less responsive to endocrine therapy than ER+/HER2- tumours. Mechanisms underpinning the differential behaviour of ER+HER2+ tumours are poorly characterised. Our aim was to identify biomarkers of response to 2 weeks’ presurgical AI treatment in ER+/HER2+ BCs. METHODS: All available ER+/HER2+ BC baseline tumours (n=342) in the POETIC trial were gene expression profiled using BC360™ (NanoString) covering intrinsic subtypes and 46 key biological signatures. Early response to AI was assessed by changes in Ki67 expression and residual Ki67 at 2 weeks (Ki672wk). Time-To-Recurrence (TTR) was estimated using Kaplan-Meier methods and Cox models adjusted for standard clinicopathological variables. New molecular subgroups (MS) were identified using consensus clustering. FINDINGS: HER2-enriched (HER2-E) subtype BCs (44.7% of the total) showed poorer Ki67 response and higher Ki672wk (p<0.0001) than non-HER2-E BCs. High expression of ERBB2 expression, homologous recombination deficiency (HRD) and TP53 mutational score were associated with poor response and immune-related signatures with High Ki672wk. Five new MS that were associated with differential response to AI were identified. HER2-E had significantly poorer TTR compared to Luminal BCs (HR 2.55, 95% CI 1.14–5.69; p=0.0222). The new MS were independent predictors of TTR, adding significant value beyond intrinsic subtypes. INTERPRETATION: Our results show HER2-E as a standardised biomarker associated with poor response to AI and worse outcome in ER+/HER2+. HRD, TP53 mutational score and immune-tumour tolerance are predictive biomarkers for poor response to AI. Lastly, novel MS identify additional non-HER2-E tumours not responding to AI with an increased risk of relapse
Knowledge sharing, knowledge transfer and SMEs: evolution, antecedents, outcomes and directions
Purpose The purpose of this paper is to systematically synthesize the extant literature of knowledge sharing (KS) and knowledge transfer (KT) in the small and medium enterprise (SME) context and to contribute with predictions of emerging themes. Design/methodology/approach Applied is a systematic literature review using three bibliometric techniques: (1) textual analysis for keywords and abstracts to identify the research hotspots, (2) co-citation analysis of references to identify the evolution of KS and KT in SME and (3) bibliographic coupling analysis of documents to synthesize antecedents and outcomes. Findings A conceptual map emerges from the review to reveal the antecedents of KS and KT at the individual, group and organizational levels. The analysis shows the strategic importance of KS and KT for the SME context. Specific findings include: (1) KS and KT are involved in enhancing SMEs strategic focus for human resources, including organizational learning, customer relations, creativity, higher profit and positive effects on operational processes and decision-making. (2) Innovation, trust and performance are identified as central human factors linked to KS and KT in SMEs. (3) Human resource (HR) management research could contribute to KS and KT in the SME domain by exploring KS- and KT-based practices, linking the emergence of innovation and innovative behaviors to these practices, leading to a better understanding of strategies that enable the long-term storage and retrieval of tacit and explicit knowledge as organizational memory in the SME context. Originality/value This paper is one of the first to systematically review KS and KT in SMEs and propose a concept map. The research adds value to the growing literature of KS and KT and exposes the need for more specific activities to support SME managers, as well as HR managers, who need to facilitate KS and KT in SMEs
Superoxide dismutase and neurological disorders
Superoxide dismutase (SOD) is a common antioxidant enzyme found majorly in living cells. The main physiological role of SOD is detoxification and maintain the redox balance, acts as a first line of defence against Reactive nitrogen species (RNS), Reactive oxygen species (ROS), and other such potentially hazardous molecules. SOD catalyses the conversion of superoxide anion free radicals (O 2 -.) into molecular oxygen (O 2) and hydrogen peroxide (H 2O 2) in the cells. Superoxide dismutases (SODs) are expressed in neurons and glial cells throughout the CNS both intracellularly and extracellularly. Endogenous oxidative stress (OS) linked with enlarged production of reactive oxygen metabolites (ROMs), inflammation, deregulation of redox balance, mitochondrial dysfunction and bioenergetic crisis are found to be prerequisite for neuronal loss in neurological diseases. Clinical and genetic studies indicate a direct correlation between mutations in SOD gene and neurodegenerative diseases, like Amyotrophic Lateral Sclerosis (ALS), Huntington’s disease (HD), Parkinson’s Disease (PD) and Alzheimer’s Disease (AD). Therefore, inhibitors of OS are considered as an optimistic approach to prevent neuronal loss. SOD mimetics like Metalloporphyrin Mn (II)-cyclic polyamines, Nitroxides and Mn (III)- Salen complexes are designed and used as therapeutic extensively in the treatment of neurological disorders. SODs and SOD mimetics are promising future therapeutics in the field of various diseases with OS-mediated pathology