Computational Fluid Dynamics Turbulence Model and Experimental Study for a Fontan Cavopulmonary Assist Device.

Head-flow HQ curves for a Fontan cavopulmonary assist device (CPAD) were measured using a blood surrogate in a mock circulatory loop and simulated with various computational fluid dynamics (CFD) models. The tests benchmarked the CFD tools for further enhancement of the CPAD design. Recommended Reynolds-Averaged Navier-Stokes (RANS) CFD approaches for the development of conventional ventricular assist devices (VAD) were found to have shortcomings when applied to the Fontan CPAD, which is designed to neutralize off-condition obstruction risks that could contribute to a major adverse event. The no-obstruction condition is achieved with a von Karman pump, utilizing large clearances and small blade heights, which challenge conventional VAD RANS-based CFD hemodynamic simulations. High-fidelity large eddy simulation (LES) is always recommended; however, this may be cost-inhibitive for optimization studies in commercial settings, thus the reliance on RANS models. This study compares head and power predictions of various RANS turbulence models, employing experimental measurements and LES results as a basis for comparison. The models include standard k-ϵ, re-normalization group k-ϵ, realizable k-ϵ, shear stress transport (SST) k-ω, SST with transitional turbulence, and Generalized k-ω. For the pressure head predictions, it was observed that the standard k-ϵ model provided far better agreement with experiment. For the rotor torque, k-ϵ predictions were 30% lower than LES, while the SST and LES torque values were near identical. For the Fontan CPAD, the findings support using LES for the final design simulations, k-ϵ model for head and general flow simulation, and SST for power, shear stress, hemolysis, and thrombogenicity predictions.

Characterization of a pulsatile rotary total artificial heart.

This article describes the properties and performance of a rotary total artificial heart (TAH) that produces inherently pulsatile flow. The hydraulic performance of the TAH was characterized using a mock circulatory loop to simulate four physiologically relevant conditions: baseline flow, increased flow, systemic hypertension, and pulmonary hypertension. The pump has a variable shuttle rate (beats per minute), percentage dwell time, and angular velocity on either side (revolutions per minute), which allows for full control of the flow rate and pulsatility over a range of healthy and pathologic pressures and flow rates. The end-to-end length and displacement volume of the TAH are 9.8 cm and 130 mL, respectively, allowing it to fit in smaller chest cavities including those of smaller adults and juvenile humans.

Longitudinal Changes Among Latino/a Immigrant Parental Acculturation and Extra-Familial Immigration-Related Stress.

Foreign-born Latino/a immigrants currently make up 12.9% of the total U.S. population. Latino/a immigrants continue to be exposed to widespread health and mental health care disparities. Scholarship focused on the needs of Latino/a immigrants continues to be characterized by multiple gaps. Latino/a immigrants and their families, particularly those with low family annual incomes, are exposed to multiple types of immigration-related stress. However, little is known about how immigration-related stress impacts couples. The objective of this investigation was to examine the interrelationship among acculturation and immigration-related stress as reported by a group of Latino/a immigrant parents who participated in a cultural adaptation parenting study. Data were provided by 78 two-parent families. The statistical approach consisted of latent growth curve analyses to examine rates of change over time. Findings indicated a potential protective role of biculturalism among Latino/a immigrant couples. Research, clinical, and policy implications are discussed.

The OregonHeart Total Artificial Heart: Design and Performance on a Mock Circulatory Loop.

Widespread use of heart transplantation is limited by the scarcity of donor organs. Total artificial heart (TAH) development has been pursued to address this shortage, especially to treat patients who require biventricular support. We have developed a novel TAH that utilizes a continuously spinning rotor that shuttles between two positions to provide pulsatile, alternating blood flow to the systemic and pulmonary circulations without artificial valves. Flow rates and pressures generated by the TAH are controlled by adjusting rotor speed, cycle frequency, and the proportion of each cycle spent pumping to either circulation. To validate the design, a TAH prototype was placed in a mock circulatory loop that simulates vascular resistance, pressure, and compliance in normal and pathophysiologic conditions. At a systemic blood pressure of 120/80 mm Hg, nominal TAH output was 7.4 L/min with instantaneous flows reaching 17 L/min. Pulmonary artery, and left and right atrial pressures were all maintained within normal ranges. To simulate implant into a patient with severe pulmonary hypertension, the pulmonary vascular resistance of the mock loop was increased to 7.5 Wood units. By increasing pump speed to the pulmonary circulation, cardiac output could be maintained at 7.4 L/min as mean pulmonary artery pressure increased to 56 mm Hg while systemic blood pressures remained normal. This in vitro testing of a novel, shuttling TAH demonstrated that cardiac output could be maintained across a range of pathophysiologic conditions including pulmonary hypertension. These experiments serve as a proof-of-concept for the design, which has proceeded to in vivo testing.

What's wrong with these people? clinicians' views of clinical couples.

Marriage and family therapy (MFT) faculty and graduate students rated the "typical" or predictable behaviors of husbands or wives coming for therapy using the Georgia Marriage Q-sort. Scores were compared with previously published scores for both "ideal" couples (i.e., showing positive behaviors, attitudes, and problem-solving skills) and a sample of 136 nonclinical, community couples. A review of correlations between MFT raters' scores for clients and the scores for "ideal" or actual community husbands or wives indicated that clinicians have negative views of both clinical husbands and wives. Such negative views of clinical husbands and wives are particularly marked in scores by MFT faculty. MFT students had a similarly negative view of clinical husbands, but such views were not evident for clinical wives. Recommendations for MFT training and implications for future research are discussed.

The Hemopump™, The First Intravascular Ventricular Assist Device.

Development of durable left ventricular assist devices (LVADs), based on rotary flow blood pumps, began in earnest after the successful implantation of a catheter-mounted axial flow blood pump via intravascular access in 1988. This device, the Hemopump, successfully supported the circulation of a patient in cardiogenic shock secondary to acute rejection of a transplanted heart. Duration of support was 46 hours, resulting in complete recovery of cardiac function and hospital discharge. In effect, this sentinel event demonstrated that continuous-flow blood pumps could be used to support patients in cardiogenic shock. This held true in spite of many widely held paradigms against rotary blood pumps regarding blood damage, diminished pulsatility, and thrombosis. At this writing, 50,000 patients have been implanted with durable LVADs based on rotary blood pumps as a bridge to cardiac transplantation or destination support as long as 10 years.

The Profession of Couple, Marital, and Family Therapy (CMFT): Defining Ourselves and Moving Forward.

The field of Couple, Marital, and Family Therapy (CMFT) has evolved and strengthened, but we still have work to do when it comes to identity, comprehensive scholarly resources, empirical support, and name brand recognition. We explore the reasons for these challenges and propose ways to address them: embracing the interdisciplinary nature of the field, consistently organizing treatment effectiveness by problem rather than by intervention model, continuing innovation in theory development, and utilizing more diverse and meaningful research methods. This approach provides a more accurate representation of the scope of practice of CMFTs, the range of mental and physical health problems we address, and the depth and extent of the existing research on the effectiveness of relational therapies.

"Changing for my kid": fatherhood experiences of Mexican-origin teen fathers involved in the justice system.

A descriptive phenomenological study was conducted with six adolescent fathers of Mexican origin on juvenile probation for a variety of serious offenses. All participants successfully completed a parenting program designed especially for teen fathers. In a series of consecutive in-depth interviews, teen fathers were asked to discuss their experiences as fathers. Four phenomena were identified from the data: (a) not giving up and deciding to be a dad, (b) figuring out my relationships after becoming a father, (c) wanting to be a good father, and (d) wanting to be Brown and a father. Findings challenge negative stereotypes associated with Mexican-origin teen fathers engaged in delinquent behaviors and describe the ways in which fatherhood became an important positive motivator in the lives of participants.

"Wanting to be a good father": experiences of adolescent fathers of Mexican descent in a teen fathers program.

Adolescent fatherhood has received limited attention in research and clinical practice. This article describes the design and implementation of a parenting program for adolescent fathers, largely minority, involved in the juvenile justice system. In the teen fathers groups, adolescent fathers were exposed to therapeutic (e.g., family-of-origin) as well as psychoeducational (e.g., child development and parenting) interventions. Findings from a descriptive phenomenological study with six former group participants indicate that the program is an effective way of assisting teen fathers in increasing their commitment as fathers as well as their involvement with their children.

Development of the Gay and Lesbian Relationship Satisfaction Scale.

This article describes the development and evaluation of the Gay and Lesbian Relationship Satisfaction Scale (GLRSS) as a measure of individuals' gay and lesbian same-gender relationship satisfaction and social support. Clinicians and researchers administer relationship satisfaction scales to persons in gay and lesbian relationships with a heteronormative assumption that scales developed and validated with opposite-gender couples measure identical relationship issues. Gay and Lesbian couples have unique concerns that influence relationship satisfaction, most notably social support. Using online recruitment and data collection, the GLRSS was evaluated with data from 275 gay and lesbian individuals in a same-gender relationship.

Integrating research and clinical training in marriage and family therapy training programs.

The future of the profession and practice of marriage and family therapy (MFT) rests with those who promote the integration of research and clinical practice. The Boulder scientist-practitioner model is useful in conceptualizing MFT training, but it is not the perfect solution. Four MFT programs (two master's and two doctoral) are featured in this article for their work in integrating research and practice. Helpful strategies presented include: Encouraging students to question the therapy process; integrating research in the curriculum and supervision; discussing the positives and negatives of empirically supported treatments; focusing on change; and developing creative classroom experiences to use within the scientist-practitioner model.

Differences in self-report measures by adolescent sex offender risk group.

Differences in self-reports among three groups of juvenile sex offenders (N = 162) were examined. Risk was defined as the sum of the following static variables based on interviews with juveniles and others and from written records: type of offense (violent or predatory = 1, not = 0), prior sex offense (any = 1, none = 0), history of sexual abuse (self or family = 1, none = 0), history of substance abuse (self or family = 1, none = 0), history of behavior problems (yes = 1, no = 0), and unstable home life (yes = 1, stable = 0). Low-risk (0 to 2 risk factors), medium-risk (3 factors), and high-risk (4 to 6 factors) groups of offenders were formed. Univariate ANCOVAs indicated that the high-risk group reported less family cohesion, more aggression, lower self-esteem, more social discomfort, and more frequent and extreme sexual fantasies. The implications of these findings for differential identification of and interventions with adolescent sex offenders are discussed.

A place for marriage and family services in employee assistance programs (EAPs): a survey of EAP client problems and needs.

Marriage and family services have not been widely recognized as part of employee assistance programs (EAP), although family and relational problems are widely cited as sources of problems on the job. EAP clients (N = 800, 97% self-referred) indicated how much family, psychological/emotional, drug, alcohol, employment-related, legal, and medical problems troubled them and the need for services in each area. Psychological/emotional (66%) and family (65%) problem areas frequently were rated "considerable" or "extreme." Both areas were rated as "considerable" or "extreme" by 48.6% of participants. In view of the evidence that marriage and family services can be effective with both family and psychological/emotional problems, professionals who are competent to provide such services have much to offer EAP programs.