The contributions of socioeconomic status, perceived stress, and depression to disability in adults with systemic lupus erythematosus

Purpose: Psychological and sociodemographic factors contribute to disability in systemic lupus erythematosus. Yet the pathways by which these factors influence disability remain unclear. The objective of this study was to evaluate a model examining socioeconomic status (SES), perceived stress, and depressive symptoms as determinants of lupus-related disability.Methods: The sample included 134 patients receiving treatment at an academic hospital. Structural equation modeling examined the direct and indirect effects of SES (income, education, and subjective social status), perceived stress (Perceived Stress Scale), and depressive symptoms (Hospital Depression Anxiety Scale depression subscale) on disability (Lupus Patient-Reported Outcome measure Physical Health and Pain-Vitality subscales).Results: Structural equation modeling confirmed that the model fit the data well. The SES exerted a direct negative effect on perceived stress (β = -0.40, p < 0.001). In turn, perceived stress predicted higher levels of depression (β = 0.72, p < 0.001), which ultimately contributed to greater disability (β = 0.53, p < 0.001). The influence of SES on disability was indirect (mediated by perceived stress and depression).Conclusions: Findings support the socioeconomic gradient in disability as mediated by perceived stress and depression, such that lower SES contributed to lupus-related disability via perceived stress and depressive symptoms.Implications for RehabilitationLow socioeconomic status, perceived stress, and depression are prognostic factors for the disability in systemic lupus erythematosus.Study findings indicate that perceived stress and depression fully mediate (account for) the negative impact of low socioeconomic status on lupus-related disability.Screening for and addressing psychological distress may enhance management of disability in lupus patients.This research demonstrates the value of a conceptual framework for identifying potentially modifiable risk factors for disability in lupus and other chronic disabling diseases.

Fabrication of Taper Free Micro-Holes Utilizing a Combined Rotating Helical Electrode and Short Voltage Pulse by ECM

Fabrication of the injection nozzle micro-hole on the aero engine is a difficult problem in today’s manufacturing industry. In addition to the size requirements, the nozzle micro-hole also requires no burr, no taper and no heat-affected zone. To solve the above problem, an ultra-short voltage pulse and a high-speed rotating helical electrode were used in electrochemical drilling (ECD) process. Firstly, a theoretical model of ECD with ultra-short voltage pulse was established to investigate the effects of many predominant parameters on machining accuracy, and the effect of rotating helical electrode on the gap flow field was analyzed. Secondly, sets of experiments were carried out to investigate the effects of many key parameters on machining accuracy and efficiency. Finally, the optimized parameters were applied to machine micro holes on 500 μm thickness of GH4169 plate, and micro-holes with the diameter of 186 μm with no taper were machined at the feed rate of 1.2 μm/s. It is proved that the proposed ECD process for fabricating micro-holes with no taper has a huge potential and broad application prospects.

Transtheoretical Model of Health Behavioral Change: A Systematic Review

Background:

Transtheoretical model (TTM) is one of the most commonly used methods in behavioral change modeling. The aim of this study was to conduct a systematic review (SR) to determine research gaps with regard to this template with an emphasis on intervention for patients with chronic diseases (CDs).

Materials and Methods:

ISI-WOS, Scopus, PubMed, SID, and Magiran databases were examined systematically and on the basis of defined criteria. Titles, abstracts, and full texts of articles retrieved were examined for the presence of defined criteria. Then finalized articles were analyzed in consensus meetings. After that, references of selected articles and full text of those meeting the criteria were also analyzed.

Results:

We screened 103 articles, excluded 27 in abstract review and 34 in full-text review, leaving 42 articles for critical appraisal. Then the references of these 42 articles were also screened. Fifty articles were excluded on abstract review and 5 on full-text review, leaving 15 articles. The result of the analysis of 57 final articles of this SR determined that 28 articles were about aspects of TTM and 5 stages of change were the most commonly used aspect. Eight articles used TTM in intervention about CDs. A total of 21 articles examined TTM's pros and cons, most of which were about TTM's pros.

Conclusions:

The majority of studies focused on the effectiveness of TTM on the behavioral change management. This finding supported the hypothesis that TTM can be applied in the prevention of CDs.

Empirical and Theoretical Modeling of Low-Frequency Noise Behavior of Ultrathin Silicon-on-Insulator MOSFETs Aiming at Low-Voltage and Low-Energy Regime

This paper theoretically revisits the low-frequency noise behavior of the inversion-channel silicon-on-insulator metal-oxide-semiconductor field-effect transistor (SOI MOSFET) and the buried-channel SOI MOSFET because the quality of both Si/SiO₂ interfaces (top and bottom) should modulate the low-frequency fluctuation characteristics of both devices. It also addresses the low-frequency noise behavior of sub-100-nm channel SOI MOSFETs. We deepen the discussion of the low-frequency noise behavior in the subthreshold bias range in order to elucidate the device’s potential for future low-voltage and low-power applications. As expected, analyses suggest that the weak inversion channel near the top surface of the SOI MOSFET is strongly influenced by interface traps near the top surface of the SOI layer because the traps are not well shielded by low-density surface inversion carriers in the subthreshold bias range. Unexpectedly, we find that the buried channel is primarily influenced by interface traps near the top surface of the SOI layer, not by traps near the bottom surface of the SOI layer. This is not due to the simplified capacitance coupling effect. These interesting characteristics of current fluctuation spectral intensity are explained well by the theoretical models proposed here.

How Lattice and Charge Fluctuations Control Carrier Dynamics in Halide Perovskites

Here we develop a microscopic approach aimed at the description of a suite of physical effects related to carrier transport in, and the optical properties of, halide perovskites. Our theory is based on the description of the nuclear dynamics to all orders and goes beyond the common assumption of linear electron-phonon coupling in describing the carrier dynamics and band gap characteristics. When combined with first-principles calculations and applied to the prototypical MAPbI₃ system, our theory explains seemingly disparate experimental findings associated with both the charge-carrier mobility and optical absorption properties, including their temperature dependencies. Our findings demonstrate that orbital-overlap fluctuations in the lead-halide structure plays a significant role in determining the optoelectronic features of halide perovskites.

Ultra-Flexible and Large-Area Textile-Based Triboelectric Nanogenerators with a Sandpaper-Induced Surface Microstructure

Wearable triboelectric nanogenerators (TENGs) have attracted interest in recent years, which demand highly flexible, scalable, and low-cost features. Here, we report an ultra-flexible, large-scale and textile-based TENG (T-TENG) for scavenging human motion energy. The triboelectric layer was derived from the polydimethylsiloxane (PDMS) film with a cost-effective paper-induced rough surface via a facile doctor-blending technology. Ag-coated chinlon fabric (ACF) with ultra-flexible, large-scale and conductive characteristics was used as the electrode. The as-fabricated PDMS-based ACF (PACF) composites possess a 240 × 300 mm² superficial area and remain highly flexible under mechanical squeezing, folding and even tearing deformation. The maximum output charge of ~21 μC and voltage of 80.40 V were therefore achieved to directly power 100 LEDs based on the high surface area of 762.73 mm² which was rationally replicated from the sandpaper of the T-TENG. Moreover, the output voltage signal can be also used as a trigger signal of a movement sensor. Importantly, the explicit theoretical model corresponding to T-TENG was quantitatively investigated under different applied force, frequency and effective surface factor.

Evaluating an integrated primary care approach to improve well-being among frail community-living older people: A theory-guided study protocol

Background

A major challenge in primary healthcare is the substantial increase in the proportion of frail community-dwelling older persons with long-term conditions and multiple complex needs. Consequently, a fundamental transformation of current models of primary care by means of implementing proactive integrated care is necessary. Therefore, an understanding of the effects of integrated primary care approaches and underlying mechanisms is essential. This article presents the design of a theory-based evaluation of an integrated primary care approach to improve well-being among frail community-living older adults, which is called “Finding and Follow-up of Frail older persons” (FFF).

First, we present a theoretical model to facilitate a sound theory-guided evaluation of integrated primary care approaches for frail community-dwelling older people. The model incorporates interrelated elements of integrated primary care approaches (e.g. proactive case finding and self-management support). Efforts to improve primary care should integrate these promising components to assure productive patient-professional interactions and to improve well-being. Moreover, cognitive and behavioral components of healthcare professionals and patients are assumed to be important. Second, we present the design of the study to evaluate the FFF approach which consists of the following key components: (1) proactive case finding, (2) case management, (3) medication review, (4) self-management support, and (5) working in multidisciplinary care teams.

Methods

The longitudinal evaluation study has a matched quasi-experimental design with one pretest and one posttest (12 month follow-up) and is conducted in the Netherlands between 2014 and 2017. Both quantitative and qualitative methods are used to evaluate effectiveness, processes, and cost-effectiveness. In total, 250 frail older persons (75 years and older) of 11 GP (general practitioner) practices that implemented the FFF approach are compared with 250 frail older patients of 4 GP practices providing care as usual. In addition, data are collected from healthcare professionals. Outcome measures are based on our theoretical model.

Discussion

The proposed evaluation study will reveal insight into the (cost)effectiveness and underlying mechanisms of the proactive integrated primary care approach FFF. A major strength of the study is the comprehensive evaluation based on a theoretical framework. The quasi-experimental design presents some challenges.

Improving the sensitivity of miniature linear ion trap mass spectrometer by a DC voltage applied on the eject electrodes

A miniaturized linear ion trap mass spectrometer with continuous atmospheric pressure interface has been built in our lab. Significant extension in mass range and reduction in power consumption have been realized by the supplemental alternating current frequency scan mode. However, relatively poor sensitivity has been witnessed, which is directly dominated by the detection efficiency of the ion detector. Theoretical analysis has been implemented to find ways to improve the detection efficiency. The results show that enhanced sensitivity can be obtained by applying a direct current voltage on the pair of electrodes in eject direction. Experiments show that the sensitivity has been improved by more than one time due to the application of direct current voltage. With this design, this homemade miniature linear ion trap mass spectrometer can be used to analyze more rarefied samples, especially to on-site chemical analysis and space application.

From fad to FAD: A theoretical formulation and proposed name change for "drunkorexia" to food and alcohol disturbance (FAD)

"Drunkorexia" is a term that has been used to describe behaviors such as restricting food intake in anticipation of alcohol consumption to offset total caloric intake, and/or to enhance the intoxicating effect of alcohol consumption. Scattered studies over the past few years have indicated the potential problematic nature of the intersection of these behaviors, yet there remain significant gaps in the operationalization of the construct, limiting research progress. In this article, we articulate limitations of the current research, including problems with the definition of the construct and a lack of theoretical guidance. We suggest a broader and more accurate phrase to guide future work with this phenomenon: Food and alcohol disturbance (FAD). Additionally, we suggest adapting Fairburn's transdiagnostic theoretical model for FAD. It is hoped these changes might provide a roadmap for future work in this area on risk factors and adaptations of current preventive and treatment approaches to focus on this emerging form of eating disturbance.

A Proposed Nursing Theory: Infant Sleep and Development

Although well positioned to work with families of young children, nurses do not yet have a theory that guides practice and research by relating infant sleep to child and family development. The authors of this paper describe a proposed theory that combines Bronfenbrenner's bioecological theory of human development with the Barnard model of parent-child interaction to inform nursing practice and research related to infant sleep and optimizing child and family development. The theory focuses on sustainability of change in family processes and infant sleep, with a goal of optimizing family wellness as the proximal environment for child development.

Comprehensive process model of clinical information interaction in primary care: results of a "best-fit" framework synthesis

Objective

To describe a new, comprehensive process model of clinical information interaction in primary care (Clinical Information Interaction Model, or CIIM) based on a systematic synthesis of published research.

Materials and Methods

We used the "best fit" framework synthesis approach. Searches were performed in PubMed, Embase, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), PsycINFO, Library and Information Science Abstracts, Library, Information Science and Technology Abstracts, and Engineering Village. Two authors reviewed articles according to inclusion and exclusion criteria. Data abstraction and content analysis of 443 published papers were used to create a model in which every element was supported by empirical research.

Results

The CIIM documents how primary care clinicians interact with information as they make point-of-care clinical decisions. The model highlights 3 major process components: (1) context, (2) activity (usual and contingent), and (3) influence. Usual activities include information processing, source-user interaction, information evaluation, selection of information, information use, clinical reasoning, and clinical decisions. Clinician characteristics, patient behaviors, and other professionals influence the process.

Discussion

The CIIM depicts the complete process of information interaction, enabling a grasp of relationships previously difficult to discern. The CIIM suggests potentially helpful functionality for clinical decision support systems (CDSSs) to support primary care, including a greater focus on information processing and use. The CIIM also documents the role of influence in clinical information interaction; influencers may affect the success of CDSS implementations.

Conclusion

The CIIM offers a new framework for achieving CDSS workflow integration and new directions for CDSS design that can support the work of diverse primary care clinicians.

Theoretical and Experimental Research on Bubble Actuated Micro-Pumps

Bubble actuated micro-pumps have great potential to be integrated into microfluidic systems to allow the independence of peripheral equipment. Previous studies on bubble actuated valveless micro-pumps have been mainly limited to experimental studies and numerical simulations due to the complex behavior of bubbles. In this paper, the construction of a mathematical model for a bubble actuated valveless micro-pump considering fluid dynamics, heat and mass transfer and bubble dynamics is described. A prototype was fabricated and tested to verify this theoretical model. The morphological evolution of the driving bubbles during the heating process was observed by a high-speed charge-coupled device (CCD) camera, the flow rate produced by the micro-pump under different working conditions was recorded and the test results were explained by the heat dissipation model. The model in this study was able to precisely predict the flow of micro-pumps in different drive modes. The principle behind defining the heating frequency and the duty cycle based on the pump chamber volume was determined. The study shows the mechanism of bubble controlling and the good prospects of bubble actuated valveless micro-pumps.

A theoretical model of resilience capacity: Drawn from the words of adult children of alcoholics

BACKGROUND

Resilience can be defined as exhibiting positive outcomes after serious threats to one's adaptation or development.

AIMS

This study aimed to suggest a theoretical model of resilience capacity by validating and extending one of the existing nursing theories of resilience-the society-to-cell model developed by Szanton and Gill. To do so, we conducted a qualitative study exploring the factors and conditions influencing adaptation in children of alcoholics (i.e., people who grew up under alcoholic parents).

METHODS

Data were collected from 22 adult children of alcoholics in South Korea via semistructured interviews. All interviews were audio-recorded and transcribed, and the data were analyzed using directed content analysis.

RESULTS

The results revealed two categories each at the society and community levels, and three categories each at the family and individual levels. No categories emerged at the physiological and cellular levels. In summary, resilience capacity is determined by the multilevel (e.g., society, community, family, and individual levels) factors that all individuals possess.

CONCLUSION

This study is meaningful in that it presents concrete goals for nurses to pursue-namely, enhancing individuals' resilience capacity-and suggests strong evidence for developing nursing intervention programs that can foster resilience capacity.

The Flow Engine Framework: A Cognitive Model of Optimal Human Experience

Flow is a well-known concept in the fields of positive and applied psychology. Examination of a large body of flow literature suggests there is a need for a conceptual model rooted in a cognitive approach to explain how this psychological phenomenon works. In this paper, we propose the Flow Engine Framework, a theoretical model explaining dynamic interactions between rearranged flow components and fundamental cognitive processes. Using an IPO framework (Inputs - Processes - Outputs) including a feedback process, we organize flow characteristics into three logically related categories: inputs (requirements for flow), mediating and moderating cognitive processes (attentional and motivational mechanisms) and outputs (subjective and objective outcomes), describing the process of the flow. Comparing flow with an engine, inputs are depicted as flow-fuel, core processes cylinder strokes and outputs as power created to provide motion.

Life Themes and Interpersonal Motivational Systems in the Narrative Self-construction

What makes unique and unrepeatable individuals is their ability to write their own story attributing meaning, sharing it through narration, giving coherence to the information related to the interpersonal motivational systems, and creating alternative hierarchies to those biologically provided by the genetic code. Through clinical narratives and narrative literature, we can observe the recurrence of specific topics, across time and different cultures. Hence, we wondered whether there are some evolutionary suggestions that guide us in the construction of the narrative-autobiographical contents. In this article we proposed a theoretical-clinical hypothesis about the existence of a biological disposition to identify as fundamental six Life Themes (LTs) that contribute to defining the image of the self and the world: Love, Personal Value, Power, Justice, Truth, and Freedom. Besides the innumerable narratives dependent upon context, there may be many ways of telling stories that, instead, would be reported to these few essential themes. A narrative review of the literature about these concepts follows the systematic explanation of the perspective about the LTs as attractors of meaning. The manuscript considers also the process of co-construction of meanings within the interpersonal relationships and the influences of these on the narratives. In particular, we focused on the importance of episodic and autobiographical memory related to the attachment and significant figures, in the construction of the personal story and the LTs. We also explained the possible clinical implications of the theoretical hypothesis of LTs. Within clinical conversations, the LTs could be expressed rigidly or, otherwise, in a confused way. The lack of narrative integration may lead to the dominance of chaos or rigidity that generates suffering. A better comprehension of the LTs in patients’ narrations could be useful to identify a narrative profile about the areas of greatest suffering related to the idea of self and the world, as well as to construct an adequate care plan.

Basic issues concerning health-related quality of life

INTRODUCTION

Chronic diseases such as cancer have a strong influence on both physical health and quality of life, which together comprise the concept of health-related quality of life (HRQoL) - in other words, the complete state of physical, social, and psychological functioning. Herein, we review the literature on the theory of HRQoL in relation to oncological diseases.

MATERIAL AND METHODS

A literature search of English-language publications that included an analysis of the conceptual models of HRQoL was performed using PubMed. The data were screened and synthesized by all authors and relevant papers were selected.

RESULTS

We outline the theoretical models most often used to conceptualize HRQoL, including the Centre for Health Promotion model from the University of Toronto, the conceptual model of Wilson and Cleary and the contextual model of Ashing-Giwa formulated specifically for cancer patients.

CONCLUSIONS

Understanding the theoretical basis of HRQoL is indispensable for valid research in this area.

Applying Multi-Theory Model (MTM) of Health Behavior Change to Predict Water Consumption Instead of Sugar-Sweetened Beverages

Background: A substantial proportion of college students to not drink enough water and consume sugar-sweetened beverages (SSBs). Consumption of SSBs is associated with weight gain, obesity, type 2 diabetes mellitus, dental carries, and increased risk for cardiovascular disease. Hence, the purpose of this study was to use the multi-theory model (MTM) in predicting initiation and sustenance of plain water consumption instead of sugar-sweetened beverages among college students.

Study design: A cross-sectional study.

Methods: In this cross-sectional study, a 37-item valid and reliable MTM-based survey was administered to college students in 2016 via Qualtrics at a large public university in the Southeastern United States. Overall, 410 students responded to the survey; of those, 174 were eligible for the study and completed it.

Results: Stepwise multiple regression analysis revealed that 61.8% of the variance in the initiation of drinking plain water instead of SSBs was explained by behavioral confidence (P<0.001) and changes in the physical environment (P<0.001). Further, 58.3% of the variance in the sustenance of drinking plain water instead of SSBs was explained by emotional transformation (P<0.001) and practice for change (P=0.001).

Conclusions: Multi-theory model of health behavior change is a robust theory for predicting plain water consumption instead of SSBs in college students. Interventions should be developed based on this theory for this target population.

Theoretical model for optical oximetry at the capillary level: exploring hemoglobin oxygen saturation through backscattering of single red blood cells

Oxygen saturation ( sO 2 ) of red blood cells (RBCs) in capillaries can indirectly assess local tissue oxygenation and metabolic function. For example, the altered retinal oxygenation in diabetic retinopathy and local hypoxia during tumor development in cancer are reflected by abnormal sO 2 of local capillary networks. However, it is far from clear whether accurate label-free optical oximetry (i.e., measuring hemoglobin sO 2 ) is feasible from dispersed RBCs at the single capillary level. The sO 2 -dependent hemoglobin absorption contrast present in optical scattering signal is complicated by geometry-dependent scattering from RBCs. We present a numerical study of backscattering spectra from single RBCs based on the first-order Born approximation, considering practical factors: RBC orientations, size variation, and deformations. We show that the oscillatory spectral behavior of RBC geometries is smoothed by variations in cell size and orientation, resulting in clear sO 2 -dependent spectral contrast. In addition, this spectral contrast persists with different mean cellular hemoglobin content and different deformations of RBCs. This study shows for the first time the feasibility of, and provides a theoretical model for, label-free optical oximetry at the single capillary level using backscattering-based imaging modalities, challenging the popular view that such measurements are impossible at the single capillary level.

Self-Care Education Programs Based on a Trans-Theoretical Model in Women Referring to Health Centers: Breast Self-Examination Behavior in Iran

Background:

Breast cancer is one of the most common cancers and a major public health problem in developing countries. However, early detection and treatment may be achieved by breast self-examination (BSE). Despite the importance of BSE in reducing the incidence of breast cancer and esultant deaths, the disease continues to be the most common cause of cancer death among women in Iran. This study aimed to determine the effects of self-care education on performance of BSE among women referring to health centers in our country.

Materials and Methods:

This quasi-experimental interventional study with pretest/posttest control group design was conducted on 168 women referred to health centers. The data were collected using a validated researcher-made questionnaire including demographic variables and trans-theoretical model constructs as well as a checklist assessing BSE behavior. The instruments were administered to groups with and without self-care education before, a week after, and 10 weeks after the intervention. Then, the data were entered into the SPSS statistical software (version 19) and analyzed using independent sample t-tests, paired sample t-test, repeated measures ANOVA, Chi-square, and Friedman tests (p<0.05).

Results:

The results showed an increase in the intervention group’s mean scores of trans-theoretical model constructs (stages of change, self-efficacy, decisional balance, and processes of change) and BSE behavior compared to the control group (p<0.001).

Conclusion:

The study confirmed the effectiveness of aneducational intervention based ona trans-theoretical model in performing BSE. Therefore, designing educational interventions based on this model is recommended to improve women’s health and reduce deaths due to breast cancer.

Reflections on the Field of Human Genetics: A Call for Increased Disease Genetics Theory

Development of human genetics theoretical models and the integration of those models with experiment and statistical evaluation are critical for scientific progress. This perspective argues that increased effort in disease genetics theory, complementing experimental, and statistical efforts, will escalate the unraveling of molecular etiologies of complex diseases. In particular, the development of new, realistic disease genetics models will help elucidate complex disease pathogenesis, and the predicted patterns in genetic data made by these models will enable the concurrent, more comprehensive statistical testing of multiple aspects of disease genetics predictions, thereby better identifying disease loci. By theoretical human genetics, I intend to encompass all investigations devoted to modeling the heritable architecture underlying disease traits and studies of the resulting principles and dynamics of such models. Hence, the scope of theoretical disease genetics work includes construction and analysis of models describing how disease-predisposing alleles (1) arise, (2) are transmitted across families and populations, and (3) interact with other risk and protective alleles across both the genome and environmental factors to produce disease states. Theoretical work improves insight into viable genetic models of diseases consistent with empirical results from linkage, transmission, and association studies as well as population genetics. Furthermore, understanding the patterns of genetic data expected under realistic disease models will enable more powerful approaches to discover disease-predisposing alleles and additional heritable factors important in common diseases. In spite of the pivotal role of disease genetics theory, such investigation is not particularly vibrant.

Ranging behavior drives parasite richness: A more parsimonious hypothesis

Parasitism is a ubiquitous interspecific interaction that may play an important role in the evolution of hosts and parasites, molding many aspects of their behavior and ecology. Detecting behavioral changes of hosts infected with parasites is not a straightforward task. Extrapolating from individual-level responses to group-level decision-making is still a much more complex challenge. The ranging behavior of hosts that live in social groups is a good example. Many hypotheses of the cause-effect relationship between this behavior and parasite diversity and load have been proposed. For instance, Brockmeyer et al. [2015, Am. J. Primatol. 77:1036-1048] recently suggested that the richness of protozoan parasites influences the daily path length of free-ranging mandrills. We believe that this explanation for the relationship contains several implicit assumptions. Therefore, we offer an alternative, more parsimonious hypothesis in which daily path length is the driver of parasite richness rather than its consequence. Our hypothesis only assumes that ranging farther exposes animals to a richer parasite diversity. We discuss the data required to test these alternative hypotheses and recall empirical evidence and theoretical modeling results supporting or rejecting their assumptions. We also propose a model of the expected outcomes in terms of species richness, load, intensity of infection, and within-group community similarity of non-lethal environmentally transmitted parasites in social animal groups showing distinct patterns of range use. Am. J. Primatol. 78:923-927, 2016. © 2016 Wiley Periodicals, Inc.

Transtheoretical Model Based Exercise Counseling Combined with Music Skipping Rope Exercise on Childhood Obesity

PURPOSE

The purpose was to evaluate the effects of a transtheoretical model (TTM) based exercise counseling offered with music skipping rope exercise on components of the TTM (stages of change, decisional balance, and self-efficacy), body mass index, glucose, and lipid profile of overweight/obese children in Korea.

METHODS

This study used a nonequivalent pretest and posttest experimental study design. A total of 75 overweight/obese children participated in the study. Eight sessions of exercise counseling combined with music skipping rope exercise for 12 weeks were offered for children in the experimental group, while one session of exercise counseling with music skipping rope exercise for 12 weeks was offered for children in the control group. Outcomes were measured at baseline, and 6 months after the intervention.

RESULTS

After the intervention, self-efficacy significantly improved among children in the experimental group (p = .049), while these children maintained their baseline BMI at 6-month follow-up (p > .05). Among children in the control group, BMI significantly increased (p < .05). Fasting blood sugar significantly increased for both groups after the intervention (p < .05). However, a greater increase was observed for the control group.

CONCLUSIONS

Our study partially supports the hypothesis that a TTM-based exercise intervention is effective in maintaining BMI and improving self-efficacy of overweight/obese children. The TTM-based counseling combined with exercise classes has potential to control weight among overweight/obese children, while involvement of parents and children in the development of the theory-based intervention may generate further benefits regarding health and well-being of overweight/obese children.

Directed and persistent movement arises from mechanochemistry of the ParA/ParB system

The segregation of DNA before cell division is essential for faithful genetic inheritance. In many bacteria, segregation of low-copy number plasmids involves an active partition system composed of a nonspecific DNA-binding ATPase, ParA, and its stimulator protein ParB. The ParA/ParB system drives directed and persistent movement of DNA cargo both in vivo and in vitro. Filament-based models akin to actin/microtubule-driven motility were proposed for plasmid segregation mediated by ParA. Recent experiments challenge this view and suggest that ParA/ParB system motility is driven by a diffusion ratchet mechanism in which ParB-coated plasmid both creates and follows a ParA gradient on the nucleoid surface. However, the detailed mechanism of ParA/ParB-mediated directed and persistent movement remains unknown. Here, we develop a theoretical model describing ParA/ParB-mediated motility. We show that the ParA/ParB system can work as a Brownian ratchet, which effectively couples the ATPase-dependent cycling of ParA-nucleoid affinity to the motion of the ParB-bound cargo. Paradoxically, this resulting processive motion relies on quenching diffusive plasmid motion through a large number of transient ParA/ParB-mediated tethers to the nucleoid surface. Our work thus sheds light on an emergent phenomenon in which nonmotor proteins work collectively via mechanochemical coupling to propel cargos-an ingenious solution shaped by evolution to cope with the lack of processive motor proteins in bacteria.

Anti-angiogenic activity of PSA-derived peptides

BACKGROUND

PSA is a biomarker for diagnosis and management of prostate cancer. PSA is known to have anti-tumorigenic activities, however, the physiological role of PSA in prostate tumor progression is not well understood.

METHODS

Five candidate peptides identified based upon computer modeling of the PSA crystal structure and hydrophobicity were synthesized at >95% purity. The peptides in a linear form, and a constrained form forced by a di-sulfide bond joining the two ends of the peptide, were investigated for anti-angiogenic activity in HUVEC.

RESULTS

None of the five PSA-mimetic peptides exhibited PSA-like serine protease activity. Two of the peptides demonstrated significant anti-angiogenic activity in HUVEC based on (i) inhibition of cell migration and invasion; (ii) inhibition of tube formation in Matrigel; (iii) anti-angiogenic activity in a sprouting assay; and (iv) altered expression of pro- and anti-angiogenic growth factors. Constrained PSA-mimetic peptides had greater anti-angiogenic activity than the corresponding linearized form. Complexing of PSA with ACT eliminated PSA enzymatic activity and reduced anti-angiogenic activity. In contrast, ACT had no effect on the anti-angiogenic effects of the linear or constrained PSA-mimetic peptides. Modeling of the ACT-PSA complex demonstrated ACT sterically blocks the anti-angiogenic activity of the two bioactive peptides.

CONCLUSIONS

The interaction of a hydrophilic domain on the surface of the PSA molecule with a target on the cell membrane of prostate endothelial and epithelial cells was responsible for the anti-angiogenic or anti-tumorigenic activity of PSA: enzymatic activity was not associated with anti-angiogenic effects. Furthermore, since PSA and ACT are both expressed within the human prostate tissue microenvironment, the balance of their expression may represent a mechanism for endogenous regulation of tissue angiogenesis.

A Model for Determining Strength for Embedded Elliptical Crack in Ultra-high-temperature Ceramics

A fracture strength model applied at room temperature for embedded elliptical crack in brittle solid was obtained. With further research on the effects of various physical mechanisms on material strength, a thermo-damage strength model for ultra-high-temperature ceramics was applied to each temperature phase. Fracture strength of TiC and the changing trends with elliptical crack shape variations under different temperatures were studied. The study showed that under low temperature, the strength is sensitive to the crack shape variation; as the temperature increases, the sensitivities become smaller. The size of ellipse's minor axes has great effect on the material strength when the ratio of ellipse's minor and major axes is lower than 0.5, even under relatively high temperatures. The effect of the minor axes of added particle on material properties thus should be considered under this condition. As the crack area is set, the fracture strength decreases firstly and then increases with the increase of ratio of ellipse's minor and major axes, and the turning point is 0.5. It suggests that for the added particles the ratio of ellipse's minor and major axes should not be 0.5. All conclusions significantly coincided with the results obtained by using the finite element software ABAQUS.