Showing papers by "University of Hartford published in 2016"

Anisotropic engineered heart tissue made from laser-cut decellularized myocardium.

Abstract: We have developed an engineered heart tissue (EHT) system that uses laser-cut sheets of decellularized myocardium as scaffolds. This material enables formation of thin muscle strips whose biomechanical characteristics are easily measured and manipulated. To create EHTs, sections of porcine myocardium were laser-cut into ribbon-like shapes, decellularized, and mounted in specialized clips for seeding and culture. Scaffolds were first tested by seeding with neonatal rat ventricular myocytes. EHTs beat synchronously by day five and exhibited robust length-dependent activation by day 21. Fiber orientation within the scaffold affected peak twitch stress, demonstrating its ability to guide cells toward physiologic contractile anisotropy. Scaffold anisotropy also made it possible to probe cellular responses to stretch as a function of fiber angle. Stretch that was aligned with the fiber direction increased expression of brain natriuretic peptide, but off-axis stretches (causing fiber shear) did not. The method also produced robust EHTs from cardiomyocytes derived from human embryonic stem cells and induced pluripotent stem cells (hiPSC). hiPSC-EHTs achieved maximum peak stress of 6.5 mN/mm2 and twitch kinetics approaching reported values from adult human trabeculae. We conclude that laser-cut EHTs are a viable platform for novel mechanotransduction experiments and characterizing the biomechanical function of patient-derived cardiomyoctyes.

The effectiveness of virtual reality distraction for reducing pain: A meta-analysis.

Abstract: Virtual reality uses computer technology to immerse the individual in a multisensory, 3-dimensional environment. This meta-analysis is the first to quantify the effect of virtual reality distraction on pain. To be included in the meta-analysis, studies were required to use a between-subjects or mixe

Overheating and passive habitability: indoor health and heat indices

Abstract: As extreme heat and weather events are predicted to increase due to global warming, the risk of human heat stress within buildings will increase. To be resilient, buildings will need the capacity to provide habitable indoor conditions without power for limited amounts of time. Additional indoor thermal standards are required for public health to address ‘passive habitability’ during power outages. Current research on building-related heat stress and numerous heat indices is examined in relation to the development of a new heat-safety metric for use in passively conditioned buildings. Most indoor overheating research relies on outdoor temperature data and has no common indoor heat index for evaluating indoor heat stress. A recommendation is made for using the wet-bulb globe temperature (WBGT) and predicted heat strain (PHS) indices for modelling and monitoring of indoor heat stress in healthy adult populations because both indices utilize the primary thermoregulation variables, have associated heat-stress ...

Performance, incentives, and needs for autonomy, competence, and relatedness: a meta-analysis

Abstract: Although self-determination theory (SDT) is one of the most widely cited theories of human motivation and function, critics have questioned the practical utility of its three needs (i.e., autonomy, competence, and relatedness) in performance contexts. We conduct a meta-analysis (k = 108, N = 30,648) to explore the magnitude and boundary conditions of need satisfaction and performance. As expected, autonomy (ρ = .28), competence (ρ = .37), and relatedness (ρ = .25) predict performance. Incentivization per se has little impact on need-satisfaction: instead, the need satisfaction → performance relationship is moderated by incentive salience. Consistent with a crowding-out hypothesis, need satisfaction matters less to performance when incentives are directly salient (ρ = .22) and more when indirectly salient (ρ = .45). Our meta-analysis demonstrates that indirectly salient incentives and need-satisfaction are indeed compatible, providing a direct response to criticisms of SDT in performance contexts. Additional unexpected findings and future directions are discussed.

Electrochemistry-based approaches to low cost, high sensitivity, automated, multiplexed protein immunoassays for cancer diagnostics

Abstract: Early detection and reliable diagnostics are keys to effectively design cancer therapies with better prognoses. The simultaneous detection of panels of biomarker proteins holds great promise as a general tool for reliable cancer diagnostics. A major challenge in designing such a panel is to decide upon a coherent group of biomarkers which have higher specificity for a given type of cancer. The second big challenge is to develop test devices to measure these biomarkers quantitatively with high sensitivity and specificity, such that there are no interferences from the complex serum or tissue matrices. Lastly, integrating all these tests into a technology that does not require exclusive training to operate, and can be used at point-of-care (POC) is another potential bottleneck in futuristic cancer diagnostics. In this article, we review electrochemistry-based tools and technologies developed and/or used in our laboratories to construct low-cost microfluidic protein arrays for the highly sensitive detection of a panel of cancer-specific biomarkers with high specificity which at the same time has the potential to be translated into POC applications.

The debt-equity financing decisions of U.S. startup firms

Abstract: We examine the debt-equity decisions of startup firms using the Kauffman Firm Survey, the largest database of U.S. startups launched in 2004. To control for sample selection bias and the correlation among financing decisions, we employ a Bivariate Probit-Tobit model. Our results show that several firm characteristics such as growth prospects, firm size, tangible assets, and selling products, as well as owner characteristics such as net worth, experience, education and ethnicity explain the debt-equity decisions in the startup year. In addition, for firms that use debt, we document traits that explain the use of a particular type of business versus personal debt. Larger firms use more business debt, whereas home-based and growth firms use more personal sources of debt. Immigrants, owners who lack work experience and those who invest more time in the business tend to rely more on personal sources of debt.

A Parallel Controlled Study of the Effectiveness of a Partially Flipped Organic Chemistry Course on Student Performance, Perceptions, and Course Completion

Abstract: Organic chemistry is very challenging to many students pursuing science careers. Flipping the classroom presents an opportunity to significantly improve student success by increasing active learning, which research shows is highly beneficial to student learning. However, flipping an entire course may seem too daunting or an instructor may simply choose to use this approach selectively. This exploratory, mixed-methods study examines the effectiveness of a partially flipped course in the first semester organic chemistry course. Two sections were taught by the author in Fall 2015: a control section (n = 28 students) using a lecture-based format, and a flipped section (n = 26 students), where 8, 75 min classes (a third of the course) were taught with flipped pedagogy. Significant improvements in test questions on flipped topics were observed, as well as a significant reduction in the course withdrawal rate. While the average overall course grade was similar in the two sections, the flipped section had 25% mor...

Undocumented Students' Experiences with Microaggressions during Their College Choice Process.

Abstract: Background/ContextAlthough millions of undocumented students are enrolled in and guaranteed free public K—12 education, their postsecondary education opportunities are stifled. Some of the barriers...

Actions speak louder than words: Outsiders' perceptions of diversity mixed messages

Abstract: To attract a gender diverse workforce, many employers use diversity statements to publicly signal that they value gender diversity. However, this often represents a misalignment between words and actions (i.e., a diversity mixed message) because most organizations are male dominated, especially in board positions. We conducted 3 studies to investigate the potentially indirect effect of such diversity mixed messages through perceived behavioral integrity on employer attractiveness. In Study 1, following a 2 × 2 design, participants (N = 225) were either shown a pro gender diversity statement or a neutral statement, in combination with a gender diverse board (4 men and 4 women) or a uniform all-male board (8 men). Participants' perceived behavioral integrity of the organization was assessed. In Study 2, participants (N = 251) either read positive or negative reviews of the organization's behavioral integrity. Employer attractiveness was then assessed. Study 3 (N = 427) investigated the impact of board gender composition on perceived behavioral integrity and employer attractiveness using a bootstrapping procedure. Both the causal-chain design of Study 1 and 2, as well as the significance test of the proposed indirect relationship in Study 3, revealed that a diversity mixed message negatively affected an organization's perceived behavioral integrity, and low behavioral integrity in turn negatively impacted employer attractiveness. In Study 3, there was also evidence for a tipping point (more than 1 woman on the board was needed) with regard to participants' perceptions of the organization's behavioral integrity. (PsycINFO Database Record

Long-term Effectiveness of Intensive Therapy in Chronic Stroke.

Abstract: Background While recent clinical trials involving robot-assisted therapy have failed to show clinically significant improvement versus conventional therapy, it is possible that a broader strategy of intensive therapy-to include robot-assisted rehabilitation-may yield clinically meaningful outcomes. Objective To test the immediate and sustained effects of intensive therapy (robot-assisted therapy plus intensive conventional therapy) on outcomes in a chronic stroke population. Methods A multivariate mixed-effects model adjusted for important covariates was established to measure the effect of intensive therapy versus usual care. A total of 127 chronic stroke patients from 4 Veterans Affairs medical centers were randomized to either robot-assisted therapy (n = 49), intensive comparison therapy (n = 50), or usual care (n = 28), in the VA-ROBOTICS randomized clinical trial. Patients were at least 6 months poststroke, of moderate-to-severe upper limb impairment. The primary outcome measure was the Fugl-Meyer Assessment at 12 and 36 weeks. Results There was significant benefit of intensive therapy over usual care on the Fugl-Meyer Assessment at 12 weeks with a mean difference of 4.0 points (95% CI = 1.3-6.7); P = .005; however, by 36 weeks, the benefit was attenuated (mean difference 3.4; 95% CI = -0.02 to 6.9; P = .05). Subgroup analyses showed significant interactions between treatment and age, treatment and time since stroke. Conclusions Motor benefits from intensive therapy compared with usual care were observed at 12 and 36 weeks posttherapy; however, this difference was attenuated at 36 weeks. Subgroups analysis showed that younger age, and a shorter time since stroke were associated with greater immediate and long-term improvement of motor function.

The Influence of Climate on the Academic and Athletic Success of Student-Athletes: Results from a Multi-Institutional National Study

Abstract: Students’ perceptions of the campus climate can affect their success and outcomes. Student-athletes’ experiences with campus life are unique. The Student-Athletes Climate Study (SACS) is a national study of over 8,000 student athletes from all NCAA sports and divisions. The purpose of the study was to examine the influence of individual and institutional characteristics, as mediated by climate, on student-athletes’ (a) academic success, (b) athletic success, and (c) athletic identity. Results indicated that differences in outcomes existed based on institutional and individual characteristics. It was also clear that climate mattered. Six of the seven climate scales influenced the outcomes, and differences in outcomes based on sexual identity, Division, and featured sport participation were more salient when climate was taken into account. Positive aspects of climate led to increases in outcomes in almost every relationship. Implications for researchers and practitioners are discussed, as well as specific suggestions of initiatives to improve the climate to promote the success of all student-athletes.

Cancer Diagnostics via Ultrasensitive Multiplexed Detection of Parathyroid Hormone-Related Peptides with a Microfluidic Immunoarray

Abstract: Parathyroid hormone-related peptide (PTHrP) is recognized as the major causative agent of humoral hypercalcemia of malignancy (HHM). The paraneoplastic PTHrP has also been implicated in tumor progression and metastasis of many human cancers. Conventional PTHrP detection methods like immunoradiometric assay (IRMA) lack the sensitivity required to measure target peptide levels prior to the development of hypercalcemia. In general, sensitive, multiplexed peptide measurement by immunoassay represents challenges that we address in this paper. We describe here the first ultrasensitive multiplexed peptide assay to measure intact PTHrP 1-173 as well as circulating N-terminal and C-terminal peptide fragments. This versatile approach should apply to almost any collection of peptides that are long enough to present binding sites for two antibodies. To target PTHrP, we employed a microfluidic immunoarray featuring a chamber for online capture of the peptides from serum onto magnetic beads decorated with massive numbe...

Trending autoregulatory indices during treatment for traumatic brain injury.

Abstract: Our goal is to use automatic data monitoring for reliable prediction of episodes of intracranial hypertension in patients with traumatic brain injury. Here we test the validity of our method on retrospective patient data. We developed the Continuous Hemodynamic Autoregulatory Monitor (CHARM), that siphons and stores signals from existing monitors in the surgical intensive care unit (SICU), efficiently compresses them, and standardizes the search for statistical relationships between any proposed index and adverse events. CHARM uses an automated event detector to reliably locate episodes of elevated intracranial pressure (ICP), while eliminating artifacts within retrospective patient data. A graphical user interface allowed data scanning, selection of criteria for events, and calculating indices. The pressure reactivity index (PRx), defined as the least square linear regression slope of intracranial pressure versus arterial BP, was calculated for a single case that spanned 259 h. CHARM collected continuous records of ABP, ICP, ECG, SpO2, and ventilation from 29 patients with TBI over an 18-month period. Analysis of a single patient showed that PRx data distribution in the single hours immediately prior to all 16 intracranial hypertensive events, significantly differed from that in the 243 h that did not precede such events (p < 0.0001). The PRx index, however, lacked sufficient resolution as a real-time predictor of IH in this patient. CHARM streamlines the search for reliable predictors of intracranial hypertension. We report statistical evidence supporting the predictive potential of the pressure reactivity index.

Hormonal and Thirst Modulated Maintenance of Fluid Balance in Young Women with Different Levels of Habitual Fluid Consumption.

Abstract: Background: Surprisingly little is known about the physiological and perceptual differences of women who consume different volumes of water each day. The purposes of this investigation were to (a) analyze blood osmolality, arginine vasopressin (AVP), and aldosterone; (b) assess the responses of physiological, thirst, and hydration indices; and (c) compare the responses of individuals with high and low total water intake (TWI; HIGH and LOW, respectively) when consuming similar volumes of water each day and when their habitual total water intake was modified. Methods: In a single-blind controlled experiment, we measured the 24 h total water intake (TWI; water + beverages + food moisture) of 120 young women. Those who consumed the highest (HIGH, 3.2 ± 0.6 L·day−1, mean ± SD) and the lowest (LOW, 1.6 ± 0.5 L·day−1) mean habitual TWI were identified and compared. Outcome variables were measured during two ad libitum baseline days, a four-day intervention of either decreased TWI (HIGH) or increased TWI (LOW), and one ad libitum recovery day. Results: During the four-day intervention, HIGH and LOW experienced differences in thirst (p = 0.002); also, a statistically significant change of AVP occurred (main effect of TWI and day, p < 0.001), with no effect (TWI or day) on aldosterone and serum osmolality. Urine osmolality and volume distinguished HIGH from LOW (p = 0.002) when they consumed similar 24 h TWI.

Bioconjugation of Antibodies and Enzyme Labels onto Magnetic Beads.

Abstract: Immunoassays employ antibodies and labels to capture and detect target macromolecular analytes, often from complex sample matrices such as serum, plasma, or saliva. The high affinity and specificity of antibody-antigen interactions makes immunoassays critically important analytical techniques for clinical diagnostics as well as other research applications in the areas of pharmaceutical and environmental analysis. Integration of magnetic beads (MBs) into immunoassays and other bioanalytical methodologies is a valuable approach to allow efficient target capture, enrichment, and convenient separation. In addition, large signal amplification can be achieved by preconcentration of the target and by attaching many thousands of enzyme labels to the MBs. These features have enabled MB-based biosensors to achieve ultra-low detection limits needed for advanced clinical diagnostics that are challenging or impossible using traditional immunoassays. MBs are employed either as mobile substrates for target analyte capture, as detection labels (or label carriers), or simultaneously as substrates and labels. For optimal assay performance, it is crucial to apply an easy, efficient, and robust bead-probe conjugation protocol, and to thoroughly characterize the bioconjugated products. Herein, we describe methods used in our laboratory to functionalize MBs with antibodies and enzyme labels for ultrasensitive detection of protein analytes. We also present detailed strategies for characterizing the MB bioconjugates.

Student-Athletes’ Perceptions of Mental Illness and Attitudes Toward Help-Seeking

Abstract: Given that there is evidence that college student-athletes may be at risk for psychological disturbances (Pinkerton, Hintz, & Barrow, 1989), and possibly underutilizing college mental health services (Watson & Kissinger, 2007), the purpose of this study was to examine attitudes toward mental illness and help seeking among college student-athletes compared to college student nonathletes. The roles that athletic identity and gender play in treatment-seeking comfort were examined. Contrary to what was hypothesized, the results showed that student-athletes and nonathletes did not significantly differ in willingness to seek mental health treatment. Student-athletes perceived significantly less discrimination toward individuals based on mental illness status.

Effect of Segmental Trunk Support on Posture and Reaching in Children With Cerebral Palsy.

Abstract: PURPOSE To test the effects of segmental trunk support on seated postural and reaching control in children with cerebral palsy. METHODS Seventeen children (age range 2-15 y, Gross Motor Function Classification System levels III-V) were classified with the Segmental Assessment of Trunk Control into mild (complete trunk control/lower lumbar deficits), moderate (thoracic/upper lumbar deficits), and severe (cervical/upper thoracic deficits). Postural and arm kinematics were measured while reaching with trunk support at axillae, mid-ribs, or pelvis. RESULTS Children in the mild group did not display changes in posture or reaching across conditions. The moderately involved group showed decrements in postural and reaching performance with pelvic compared with higher supports (P < .01). Children in the severe group were unable to maintain posture with pelvic support and showed postural deficiencies with mid-ribs compared with axillae support (P < .01). CONCLUSIONS Children with cerebral palsy and trunk dysfunction demonstrate improved motor performance when the external assistance matches their intrinsic level of trunk control.

A literature review of tourism management (1990–2013): a content analysis perspective

Abstract: Tourism activities can refer to an extension of a brand–consumer relationship. While growth in many industries is flat, worldwide tourism revenues continue to grow. A literature review is not only a crucial endeavour for any academic research, but also the foundation and inspiration for substantial, useful research. Among extant studies on tourism management (TM), few are on literature review while most are concerned with specific issues or countries/areas. This paper aims to draw up an integrated framework of TM. Little effort has been made to systematically examine the vast TM-related literature so as to facilitate better understandings of TM. To eliminate the gap among the extant studies and develop the TM trajectory, a content analysis was undertaken using keywords “TM” in 5 online electronic databases from 1990 to 2013. Based on 773 articles, we discovered the number of publications on TM has significantly increased since 2000 and a steady growth since 2008. While 773 articles are scattered across 19...

Competing Discourses and Meaning Making in Talk about Romantic Partners’ Cell-Phone Contact with Non-Present Others

Abstract: Focus groups were conducted with 51 college students to examine how participants engaged in meaning making about the presence and use of cell phones with non-present others while in the context of dating and spending time with romantic partners. Grounded in relational dialectics theory, qualitative analysis revealed two sets of competing discourses at play in college students’ talk about cell phones: discourses of community and romance and discourses of control and freedom. The interplay of these competing discourses illuminated participants’ struggles with being available to others while trying to provide attention to their dating partners. Theoretical and practical implications are discussed.

Strengthening the Coordination of Pediatric Mental Health and Medical Care: Piloting a Collaborative Model for Freestanding Practices

Abstract: Collaborative pediatric mental health and primary care is increasingly recognized as optimal for meeting the needs of children with mental health problems. This paper describes the challenges faced by freestanding specialty mental health clinics and pediatric health practices to provide such coordinated mind-and-body treatment. It describes critical elements of a proactive approach to achieving collaborative pediatric care under real-world circumstances using the patient-centered medical home neighborhood (PCMH-N) model. The current study evaluates the field test of the practitioner-informed model to facilitate interdisciplinary collaboration (PIM-FIC), a systematic approach to improving inter-professional collaboration by building relationships and enhancing communication between pediatric mental health and primary care practices. Thirty-nine providers at two mental health and two pediatric primary care practices participated in a pilot project and completed surveys prior to and following their participation. Key informant interviews were also conducted prior to the project. Participating practitioners’ survey and interview responses indicate that the quantity and quality of communication between pediatric mental and medical health care providers increased post-project, as did satisfaction with overall collaboration. Improving relationships and communication are first steps in building the infrastructure to support effective coordinated care. Project results highlight practical and easily implemented strategies that pediatric mental health and primary care practices can take to strengthen their collaboration. Findings also suggest a need for collaborative care policies and competencies for child mental health providers working in freestanding practices within the PCMH-N.

A combined assessment of air and noise pollution on the High Line, New York City

Abstract: The High Line is an elevated public park in New York City, transformed from an unused freight rail line. Pedestrians walking through Manhattan’s West Side can walk either on the High Line or on a footpath below. Using Manhattan as a laboratory, this paper offers a combined assessment of noise and particulate matter pollution for its pedestrians. Noise and PM2.5 levels were recorded simultaneously for two cases (i) pedestrians walking on a footpath alongside road traffic and (ii) pedestrians walking on the elevated High Line. Testing took places over three days in autumn 2014. Results were analysed to investigate if pedestrians using the High Line would have a lower pollution exposure to those using the footpath below. Results showed statistically significant differences between the upper and lower levels in exposure to both pollution types. In order to quantify the overall impact, results are expressed through a combined air–noise pollution index. This index indicates that the average reduction in PM2.5 and noise pollution along the High Line compared to the footpath below is approximately 37%.

Telecommuting: What? Why? When? and How?

Abstract: Given changing work demands, organizations are increasingly reliant on the use of telecommuting. The overarching goal of this chapter is to provide organizations with evidence-based actionable tools for effective telecommuting arrangements. Although telecommuting has grown over the past several decades, scholars and practitioners have not yet developed a comprehensive understanding of what telecommuting is, why it should (and should not) be used, when it is appropriate, and how it can be successfully implemented. Therefore, the purpose of this chapter is to review (1) the concept of telecommuting and its various forms (what?), (2) the consequences of telecommuting, both positive and negative for employees and organizations (why?), (3) antecedents of effective telecommuting (when?), and (4) recommendations for best practices (how?). We conclude the chapter with considerations for the future of telecommuting.

Gender, Entrepreneurship, and Firm Performance: Recent Research and Considerations of Context

Abstract: Conventional wisdom asserts that women-owned firms underperform firms owned by men Studies reveal, however, that women and men do not differ in measures of firm survival or profitability when we control for factors such as industry, firm size, and firm age Gender differences persist, however, in measures of firm size and growth Recent research suggests that this continued discrepancy is due to gender differences in resource attributes combined with differences in motivations, goals, and attitudes Thus, the performance of women-owned firms needs to be viewed within the context of the goals and objectives that women establish for their firms as well as where they are in their life cycle