274 research outputs found
Baby Boomers\u27 Feelings on the Relationship Between Price and Quality
This thesis will focus on the study of Baby Boomers and the impact their particular generation has upon the type of products they purchase.
Marketing research has indicated that generational data can be very helpful. Generational factors provide a framework for understanding the marketplace. Many marketers who want to appeal to Baby Boomers attempt to recognize what interests Boomers. A fundamental truth is that marketers who take into account age group have an important competitive advantage over those who do not.
Research has also indicated that Baby Boomers show some loyalty to brand names. They look at quality as a status symbol, and purchase accordingly. Many Boomers have a large amount of disposable income and equity. They recognize that many quality products cost a premium and are willing and able to pay that extra cost.
The purpose of the present study is to investigate Baby Boomers and their responses on the relationship between a product\u27s price and quality. Specifically, the survey instrument\u27s purpose is to calculate, through data analysis, the possibility of a positive correlation between price and quality in the eyes of Baby Boomers.
Forty-nine persons of working age participated in the study. Among the survey respondents, fifty-five percent were male, and forty-five percent were female. The subjects were of aJI ages. Specifically, fifty-five percent of the respondents qualified as Baby Boomers. In order to prove or disprove the hypothesis, a survey instrument was administered on an anonymous level. The survey consisted of thirty questions, divided by product category. The data were analyzed using Pearson\u27s Product-Moment Correlation Coefficient. It is the most popular technique in data analysis.
Results of the analysis produced evidence that the hypothesis could be supported. However, a positive correlation was also calculated for the other subjects, those not part of the Baby Boomer generation
Safety of overlapping inpatient orthopaedic surgery: A multicenter study
BackgroundAlthough overlapping surgery is used to maximize efficiency, more empirical data are needed to guide patient safety. We conducted a retrospective cohort study to evaluate the safety of overlapping inpatient orthopaedic surgery, as judged by the occurrence of perioperative complications.MethodsAll inpatient orthopaedic surgical procedures performed at 5 academic institutions from January 1, 2015, to December 31, 2015, were included. Overlapping surgery was defined as 2 skin incisions open simultaneously for 1 surgeon. In comparing patients who underwent overlapping surgery with those who underwent non-overlapping surgery, the primary outcome was the occurrence of a perioperative complication within 30 days of the surgical procedure, and secondary outcomes included all-cause 30-day readmission, length of stay, and mortality. To determine if there was an association between overlapping surgery and a perioperative complication, we tested for non-inferiority of overlapping surgery, assuming a null hypothesis of an increased risk of 50%. We used an inverse probability of treatment weighted regression model adjusted for institution, procedure type, demographic characteristics (age, sex, race, comorbidities), admission type, admission severity of illness, and clustering by surgeon.ResultsAmong 14,135 cases, the frequency of overlapping surgery was 40%. The frequencies of perioperative complications were 1% in the overlapping surgery group and 2% in the non-overlapping surgery group. The overlapping surgery group was non-inferior to the non-overlapping surgery group (odds ratio [OR], 0.61 [90% confidence interval (CI), 0.45 to 0.83]; p < 0.001), with reduced odds of perioperative complications (OR, 0.61 [95% CI, 0.43 to 0.88]; p = 0.009). For secondary outcomes, there was a significantly lower chance of all-cause 30-day readmission in the overlapping surgery group (OR, 0.67 [95% CI, 0.52 to 0.87]; p = 0.003) and shorter length of stay (e, 0.94 [95% CI, 0.89 to 0.99]; p = 0.012). There was no difference in mortality.ConclusionsOur results suggest that overlapping inpatient orthopaedic surgery does not introduce additional perioperative risk for the complications that we evaluated. The suitability of this practice should be determined by individual surgeons on a case-by-case basis with appropriate informed consent.Level of evidenceTherapeutic Level III. See Instructions for Authors for a complete description of levels of evidence
A perpetual switching system in pulmonary capillaries
Of the 300 billion capillaries in the human lung, a small fraction meet normal oxygen requirements at rest, with the remainder forming a large reserve. The maximum oxygen demands of the acute stress response require that the reserve capillaries are rapidly recruited. To remain primed for emergencies, the normal cardiac output must be parceled throughout the capillary bed to maintain low opening pressures. The flow-distributing system requires complex switching. Because the pulmonary microcirculation contains contractile machinery, one hypothesis posits an active switching system. The opposing hypothesis is based on passive switching that requires no regulation. Both hypotheses were tested ex vivo in canine lung lobes. The lobes were perfused first with autologous blood, and capillary switching patterns were recorded by videomicroscopy. Next, the vasculature of the lobes was saline flushed, fixed by glutaraldehyde perfusion, flushed again, and then reperfused with the original, unfixed blood. Flow patterns through the same capillaries were recorded again. The 16-min-long videos were divided into 4-s increments. Each capillary segment was recorded as being perfused if at least one red blood cell crossed the entire segment. Otherwise it was recorded as unperfused. These binary measurements were made manually for each segment during every 4 s throughout the 16-min recordings of the fresh and fixed capillaries (>60,000 measurements). Unexpectedly, the switching patterns did not change after fixation. We conclude that the pulmonary capillaries can remain primed for emergencies without requiring regulation: no detectors, no feedback loops, and no effectors-a rare system in biology. NEW & NOTEWORTHY The fluctuating flow patterns of red blood cells within the pulmonary capillary networks have been assumed to be actively controlled within the pulmonary microcirculation. Here we show that the capillary flow switching patterns in the same network are the same whether the lungs are fresh or fixed. This unexpected observation can be successfully explained by a new model of pulmonary capillary flow based on chaos theory and fractal mathematics
Microvascular inflammatory responses to ceramide and cigarette smoke in the intact rat assessed with intravital two-photon microscopy
poster abstractsmoke, characterized by alterations of the alveolar barrier function. We investigated this hypothesis by utilizing a novel application of intravital two-photon excitation microscopy (TPM) of the lung in a living, breathing animal.
Methods: We first developed a technique of TPM to permit imaging of the lung maintained within the thoracic cavity of an intact rat. To accomplish this, we optimized the lung-microscope interface with an imaging window uniquely designed to minimize cardiac and respiratory motion during TPM acquisitions. To investigate alveolar barrier disruption in real time, we utilized intravenous (i.v.) fluorescent probes to examine changes in alveolar leukocyte trafficking and microvascular barrier function in response to i.v. ceramide (C16:0 PEG, 10 mg/kg), and to cigarette smoke extract (CSE) delivered i.v. (1ml/kg) or intratracheally via a nebulizer (2mL/kg).
Results: We performed intravital TPM monitoring of the lung microcirculation of a living rat with maintained physiological cardio-pulmonary parameters for up to 3h. Time-lapse and 3-D reconstruction images revealed heterogeneous extravasation of FITC-labeled serum albumin from the alveolar microcirculation into the alveolar airspaces in response to ceramide, in a dose-dependent manner. Further, we noted that in response to both ceramide and to CSE, leukocytes accumulated in the lung parenchyma and demonstrated reduced mobility through the microcirculation, suggesting increased adhesion to the endothelium. Intratracheal administration of CSE caused increased extravasation of leukocytes into alveolar spaces within 10 minutes.
Conclusions: We developed approaches that permit the application of intravital TPM to lung with no motion artifacts from the breathing and cardiac cycles. This approach permits visualization of the lung subpleural parenchyma with a high resolution. Both gross and subtle inflammatory changes that reflect alveolar epithelial and/or endothelial barrier dysfunction can be assessed with this methodology
Programmable Thermostat Module Upgrade for the Multipurpose Logistics Module
The STS-121/ULF 1.1 mission was the maiden flight of the programmable thermostat module (PTM) system used to control the 28 V shell heaters on the multi-purpose logistics module (MPLM). These PTMs, in conjunction with a data recorder module (DRM), provide continuous closed loop temperature control and data recording of MPLM on-orbit heater operations. This Technical Memorandum discusses the hardware design, development, test, and verification (DDT&V) activities performed at the Marshall Space Flight Center as well as the operational implementation and mission performance
Quantification of Cytokeratin 5 mRNA Expression in the Circulation of Healthy Human Subjects and after Lung Transplantation
Circulating epithelial progenitor cells are important for repair of the airway epithelium in a mouse model of tracheal transplantation. We therefore hypothesized that circulating epithelial progenitor cells would also be present in normal human subjects and could be important for repair of the airway after lung injury. As lung transplantation is associated with lung injury, which is severe early on and exacerbated during episodes of infection and rejection, we hypothesized that circulating epithelial progenitor cell levels could predict clinical outcome following lung transplantation.Quantitative Real Time PCR was performed to determine peripheral blood mRNA levels of cytokeratin 5, a previously characterized marker of circulating epithelial progenitor cells. Cytokeratin 5 levels were evaluated in healthy human subjects, in lung transplant recipients immediately post-transplant and serially thereafter, and in heart transplant recipients. All normal human subjects examined expressed cytokeratin 5 in their buffy coat in amounts that were not significantly influenced by age or gender. There was a profound, statistically significant decrease in cytokeratin 5 mRNA expression levels in lung transplant patients compared to healthy human subjects (p = 3.1x10(-13)) and to heart transplant recipients. There was a moderate negative correlation between improved circulating cytokeratin 5 mRNA levels in lung transplant recipients with recovering lung function, as measured by improved FEV1 values (rho = -0.39).Levels of cytokeratin 5 mRNA, a proxy marker for circulating epithelial progenitor cells, inversely correlated with disease status in lung transplant recipients. It may therefore serve as a biomarker of the clinical outcome of lung transplant patients and potentially other patients with airway injury
The development of path integration: combining estimations of distance and heading
Efficient daily navigation is underpinned by path integration, the mechanism by which we use self-movement information to update our position in space. This process is well-understood in adulthood, but there has been relatively little study of path integration in childhood, leading to an underrepresentation in accounts of navigational development. Previous research has shown that calculation of distance and heading both tend to be less accurate in children as they are in adults, although there have been no studies of the combined calculation of distance and heading that typifies naturalistic path integration. In the present study 5-year-olds and 7-year-olds took part in a triangle-completion task, where they were required to return to the startpoint of a multi-element path using only idiothetic information. Performance was compared to a sample of adult participants, who were found to be more accurate than children on measures of landing error, heading error, and distance error. 7-year-olds were significantly more accurate than 5-year-olds on measures of landing error and heading error, although the difference between groups was much smaller for distance error. All measures were reliably correlated with age, demonstrating a clear development of path integration abilities within the age range tested. Taken together, these data make a strong case for the inclusion of path integration within developmental models of spatial navigational processing
Protein expression based multimarker analysis of breast cancer samples
<p>Abstract</p> <p>Background</p> <p>Tissue microarray (TMA) data are commonly used to validate the prognostic accuracy of tumor markers. For example, breast cancer TMA data have led to the identification of several promising prognostic markers of survival time. Several studies have shown that TMA data can also be used to cluster patients into clinically distinct groups. Here we use breast cancer TMA data to cluster patients into distinct prognostic groups.</p> <p>Methods</p> <p>We apply weighted correlation network analysis (WGCNA) to TMA data consisting of 26 putative tumor biomarkers measured on 82 breast cancer patients. Based on this analysis we identify three groups of patients with low (5.4%), moderate (22%) and high (50%) mortality rates, respectively. We then develop a simple threshold rule using a subset of three markers (p53, Na-KATPase-β1, and TGF β receptor II) that can approximately define these mortality groups. We compare the results of this correlation network analysis with results from a standard Cox regression analysis.</p> <p>Results</p> <p>We find that the rule-based grouping variable (referred to as WGCNA*) is an independent predictor of survival time. While WGCNA* is based on protein measurements (TMA data), it validated in two independent Affymetrix microarray gene expression data (which measure mRNA abundance). We find that the WGCNA patient groups differed by 35% from mortality groups defined by a more conventional stepwise Cox regression analysis approach.</p> <p>Conclusions</p> <p>We show that correlation network methods, which are primarily used to analyze the relationships between gene products, are also useful for analyzing the relationships between patients and for defining distinct patient groups based on TMA data. We identify a rule based on three tumor markers for predicting breast cancer survival outcomes.</p
Racial/Ethnic Differences in Perceived Smoking Prevalence: Evidence from a National Survey of Teens
Prior studies show that perceived smoking prevalence is a significant predictor of smoking initiation. In this study, we examine racial/ethnic differences in perceived smoking prevalence and racial/ethnic differences in exposure to contextual factors associated with perceived smoking prevalence. We used cross-sectional time series data from the Legacy Media Tracking Surveys (LMTS), a national sample of 35,000 12- to 17-year-olds in the United States. Perceived smoking prevalence was the primary outcome variable, measured using an LMTS question: âOut of every 10 people your age, how many do you think smoke?â Multivariable models were estimated to assess the association between perceived smoking prevalence; race/ethnicity; and exposure to social contextual factors. Findings indicate that African American, Hispanic, and American Indian youth exhibit the highest rates of perceived smoking prevalence, while white and Asian youth exhibit the lowest. Minority youth are also disproportionately exposed to social contextual factors that are correlated with high perceived smoking prevalence. These findings suggest that disproportionate exposure to social contextual factors may partially explain why minority youth exhibit such high levels of perceived smoking prevalence
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