1,547 research outputs found
Placental weight and mortality in premenopausal breast cancer by tumor characteristics
Placental weight may be regarded as an indirect marker of hormone exposures during pregnancy. There is epidemiological evidence that breast cancer mortality in premenopausal women increases with placental weight in the most recent pregnancy. We investigated if this association differs by tumor characteristics, including expression of estrogen and progesterone receptors. In a Swedish population-based cohort, we followed 1,067 women with premenopausal breast cancer diagnosed from 1992 to 2006. Using Cox regression models, we estimated hazard ratios for the association between placental weight and risk of premenopausal breast cancer mortality. In stratified analyses, we estimated mortality risks in subjects with different tumor stages, estrogen receptor (ER) or progesterone receptor (PR) status. Compared with women with placental weight less than 600 g, women with a placental weight between 600 and 699 g were at a 50 % increased risk of mortality, however, not significant change in risk was observed for women with placental weight �700 g. Mortality risks associated with higher placental weight were more pronounced among ER- and PR- breast cancer tumors, where both a placental weight 600-699 g and �700 g were associated with a more than doubled mortality risks compared with tumors among women with placental weight less than 600 g. Moreover, stratified analyses for joint receptor status revealed that a consistent increased mortality risk by placental weight was only apparent in women with ER-/PR- breast cancer. The increased mortality risk in premenopausal breast cancer associated with higher placental weight was most pronounced among ER- and PR- tumors. © 2012 Springer Science+Business Media New York
Easing the Transition from Clinician to Nurse Educator: An Integrative Literature Review
Background: Experienced clinicians who choose to become academic nurse educators bring to their new faculty role strong clinical skills and a desire to influence the next generation of nurses. However, many find themselves unprepared for the challenges they encounter. Intentional mentoring is needed to ease their transition from clinician to nurse educator. Method: An integrative literature review was conducted to identify the essential components of a comprehensive mentoring program to facilitate a positive transition experience from expert clinician to novice nursing faculty. Searches were conducted of the ProQuest Central and CINAHL databases for peer-reviewed articles. Results: A review of 17 publications and seven Web sites identified formal preparation for teaching, guidance navigating the academic culture, and a structured mentoring program as essential to clinicians’ successful transition to academic nursing faculty. Conclusion: Sustainable mentoring programs require recognition of mentoring as central to nursing education and administrative investment of resources
New types of bialgebras arising from the Hopf equation
New types of bialgebras arising from the Hopf equation (pentagonal equation)
are introduced and studied. They will play from the Hopf equation the same role
as the co-quasitriangular do from the quantum Yang Baxter equation.Comment: Latex2e, Comm Algebra, in pres
Thin-film chemical sensors based on electron tunneling
The physical mechanisms underlying a novel chemical sensor based on electron tunneling in metal-insulator-metal (MIM) tunnel junctions were studied. Chemical sensors based on electron tunneling were shown to be sensitive to a variety of substances that include iodine, mercury, bismuth, ethylenedibromide, and ethylenedichloride. A sensitivity of 13 parts per billion of iodine dissolved in hexane was demonstrated. The physical mechanisms involved in the chemical sensitivity of these devices were determined to be the chemical alteration of the surface electronic structure of the top metal electrode in the MIM structure. In addition, electroreflectance spectroscopy (ERS) was studied as a complementary surface-sensitive technique. ERS was shown to be sensitive to both iodine and mercury. Electrolyte electroreflectance and solid-state MIM electroreflectance revealed qualitatively the same chemical response. A modified thin-film structure was also studied in which a chemically active layer was introduced at the top Metal-Insulator interface of the MIM devices. Cobalt phthalocyanine was used for the chemically active layer in this study. Devices modified in this way were shown to be sensitive to iodine and nitrogen dioxide. The chemical sensitivity of the modified structure was due to conductance changes in the active layer
Comparison maps for relatively free resolutions
Let Λ be a commutative ring, A an augmented differential graded algebra over Λ (briefly, DGA-algebra) and X be a relatively free resolution of Λ over A. The standard bar resolution of Λ over A, denoted by B(A), provides an example of a resolution of this kind. The comparison theorem gives inductive formulae f : B(A)→X and g : X→B(A) termed comparison maps. In case that fg=1 X and A is connected, we show that X is endowed a A ∞ -tensor product structure. In case that A is in addition commutative then (X,μ X ) is shown to be a commutative DGA-algebra with the product μ X =f*(g⊗g) (* is the shuffle product in B(A)). Furthermore, f and g are algebra maps. We give an example in order to illustrate the main results of this paper
Can low-carbon options change conditions for expanding energy access in Africa?
This discussion brief examines how low-carbon options are being used to expand energy access and electrification; the incentives and barriers to using low-carbon options; and the broader policy context
What health inequalities exist in access to, outcomes from and experience of treatment for lung cancer?: A scoping review
Objectives: Lung cancer (LC) continues to be the leading cause of cancer-related deaths and while there have been significant improvements in overall survival, this gain is not equally distributed. To address health inequalities (HIs), it is vital to identify whether and where they exist. This paper reviews existing literature on what HIs impact LC care and where these manifest on the care pathway. Design: A systematic scoping review based on Arksey and O’Malley’s five-stage framework. Data sources: Multiple databases (EMBASE, HMIC, Medline, PsycINFO, PubMed) were used to retrieve articles. Eligibility criteria: Search limits were set to retrieve articles published between January 2012 and April 2022. Papers examining LC along with domains of HI were included. Two authors screened papers and independently assessed full texts. Data extraction and synthesis: HIs were categorised according to: (a) HI domains: Protected Characteristics (PC); Socioeconomic and Deprivation Factors (SDF); Geographical Region (GR); Vulnerable or Socially Excluded Groups (VSG); and (b) where on the LC pathway (access to, outcomes from, experience of care) inequalities manifest. Data were extracted by two authors and collated in a spreadsheet for structured analysis and interpretation. Results: 41 papers were included. The most studied domain was PC (32/41), followed by SDF (19/41), GR (18/41) and VSG (13/41). Most studies investigated differences in access (31/41) or outcomes (27/41), with few (4/41) exploring experience inequalities. Evidence showed race, rural residence and being part of a VSG impacted the access to LC diagnosis, treatment and supportive care. Additionally, rural residence, older age or male sex negatively impacted survival and mortality. The relationship between outcomes and other factors (eg, race, deprivation) showed mixed results. Conclusions: Findings offer an opportunity to reflect on the understanding of HIs in LC care and provide a platform to consider targeted efforts to improve equity of access, outcomes and experience for patients
Ectopic expression of alkaline phosphatase in proximal tubular brush border membrane of human renal cell carcinoma
AbstractThe present study was conducted to find out any alteration in the expression and activity of alkaline phosphatase in the brush border membrane (BBM) from renal cell carcinoma (RCC) in comparison to normal renal BBM. The specific activity of alkaline phosphatase was drastically reduced in homogenate as well as BBM from RCC kidney when compared to ALP activity in BBM of normal kidney. Kinetic studies revealed that diminished activity of alkaline phosphatase in BBM isolated from RCC was fraternized with decrease in maximal velocity (Vmax) and increase in affinity constant (Km) of the enzyme. SDS-PAGE studies showed that the BBM proteins having molecular weights ranging from 95 to 170 kDa were poorly expressed in RCC BBM in relative to normal kidney BBM. Incubation of SDS-PAGE gel with BCIP/NBT dye clearly showed that the expression of ALP in tumor renal BBM was markedly reduced as compared to normal kidney. Further, Western blot analysis using anti-alkaline phosphatase antibody also confirmed the reduced expression of ALP in tumor renal BBM. Lipid composition in reference to phospholipids, glycolipids and cholesterol in tumor renal BBM was altered to that of normal renal BBM, indicating alteration in membrane fluidity of tumor renal BBM
The Hopf modules category and the Hopf equation
We study the Hopf equation which is equivalent to the pentagonal equation,
from operator algebras. A FRT type theorem is given and new types of quantum
groups are constructed. The key role is played now by the classical Hopf
modules category. As an application, a five dimensional noncommutative
noncocommutative bialgebra is given.Comment: 30 pages, Letax2e, Comm. Algebra in pres
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