Layered Fabrication of Branched Networks Using Lindenmayer Systems

A current challenge impeding the growth of bone tissue engineering is the lack of functional scaffolds of geometric sizes greater than 10mm due to the inability of cells to survive deep within the scaffold. It is hypothesized that these scaffolds must have an inbuilt nutrient distribution network to sustain the uniform growth of cells. In this paper, we seek to enhance the design and layered fabrication of scaffold internal architecture through the development of Lindenmayer systems, a graphical language based theory to create nutrient delivery networks. The scaffolds are fabricated using the Texas Instruments DLP™ system through UV‐photopolymerization to produce polyethylene glycol hydrogels with internal branch structures. The paper will discuss the Lindenmayer system, process planning algorithms, layered fabrication of samples, challenges and future tasks.Mechanical Engineerin

Characterization of an embedded RF-MEMS switch

An RF-MEMS capacitive switch for mm-wave integrated circuits, embedded in the BEOL of 0.25μm BiCMOS process, has been characterized. First, a mechanical model based on Finite-Element-Method (FEM) was developed by taking the residual stress of the thin film membrane into account. The pull-in voltage and the capacitance values obtained with the mechanical model agree very well with the measured values. Moreover, S-parameters were extracted using Electromagnetic (EM) solver. The data observed in this way also agree well with the experimental ones measured up to 110GHz. The developed RF model was applied to a transmit/receive (T/R) antenna switch design. The results proved the feasibility of using the FEM model in circuit simulations for the development of RF-MEMS switch embedded, single-chip multi-band RF ICs

Sprint interval training (SIT) reduces serum epidermal growth factor (EGF), but not other inflammatory cytokines in trained older men

Purpose The present study aimed to investigate the effect of age on circulating pro- and anti-inflammatory cytokines and growth factors. A secondary aim was to investigate whether a novel sprint interval training (SIT) intervention (3 × 20 s ‘all out’ static sprints, twice a week for 8 weeks) would affect inflammatory markers in older men. Methods Nine older men [68 (1) years] and eleven younger men [28 (2) years] comprised the younger group. Aerobic fitness and inflammatory markers were taken at baseline for both groups and following the SIT intervention for the older group. Results Interleukin (IL)-8, vascular endothelial growth factor (VEGF), and monocyte chemoattractant protein-1 (MCP-1) were unchanged for the older and younger groups at baseline (IL-8, p = 0.819; MCP-1, p = 0.248; VEGF, p = 0.264). Epidermal growth factor (EGF) was greater in the older group compared to the younger group at baseline [142 (20) pg mL−1 and 60 (12) pg mL−1, respectively, p = 0.001, Cohen's d = 1.64]. Following SIT, older men decreased EGF to 100 (12) pg mL−1 which was similar to that of young men who did not undergo training (p = 0.113, Cohen's d = 1.07). Conclusion Older aerobically trained men have greater serum EGF than younger aerobically trained men. A novel SIT intervention in older men can shift circulating EGF towards trained younger concentrations. As lower EGF has previously been associated with longevity in C. elegans, the manipulative effect of SIT on EGF in healthy ageing in the human may be of further interest

High Intensity Interval Training (HIIT) as a Potential Countermeasure for Phenotypic Characteristics of Sarcopenia: A Scoping Review

Background: Sarcopenia is defined as a progressive and generalized loss of skeletal muscle quantity and function associated predominantly with aging. Physical activity appears the most promising intervention to attenuate sarcopenia, yet physical activity guidelines are rarely met. In recent years high intensity interval training (HIIT) has garnered interested in athletic populations, clinical populations, and general population alike. There is emerging evidence of the efficacy of HIIT in the young old (i.e. seventh decade of life), yet data concerning the oldest old (i.e., ninth decade of life onwards), and those diagnosed with sarcopenic are sparse. Objectives: In this scoping review of the literature, we aggregated information regarding HIIT as a potential intervention to attenuate phenotypic characteristics of sarcopenia. Eligibility Criteria: Original investigations concerning the impact of HIIT on muscle function, muscle quantity or quality, and physical performance in older individuals (mean age ≥60 years of age) were considered. Sources of Evidence: Five electronic databases (Medline, EMBASE, Web of Science, Scopus, and the Cochrane Central Register of Controlled Trials [CENTRAL]) were searched. Methods: A scoping review was conducted using the Arksey and O'Malley methodological framework (2005). Review selection and characterization were performed by two independent reviewers using pretested forms. Results: Authors reviewed 1,063 titles and abstracts for inclusion with 74 selected for full text review. Thirty-two studies were analyzed. Twenty-seven studies had a mean participant age in the 60s, two in the 70s, and three in the 80s. There were 20 studies which examined the effect of HIIT on muscle function, 22 which examined muscle quantity, and 12 which examined physical performance. HIIT was generally effective in Improving muscle function and physical performance compared to non-exercised controls, moderate intensity continuous training, or pre-HIIT (study design-dependent), with more ambiguity concerning muscle quantity. Conclusions: Most studies presented herein utilized outcome measures defined by the European Working Group on Sarcopenia in Older People (EWGSOP). However, there are too few studies investigating any form of HIIT in the oldest old (i.e., ≥80 years of age), or those already sarcopenic. Therefore, more intervention studies are needed in this population

Hacking the Non-Technical Brain: Maximizing Retention in a Core Introductory IT Course

Maximizing student retention of, and ability to apply, technical material in introductory information technology courses is a complex task, especially with respect to the general student population. This population struggles with the application of programming concepts in the time-constrained testing environment. Our study considers the implementation of daily quizzes in a core-curriculum information technology and programming course as a means to improve student concept retention and application. Between the first and second exams, the instructors implemented a series of high-frequency, no-risk quizzes. Of the four sections of the course that each instructor taught, two sections each were provided with the quizzes as the experimental group and two remained with the standard curriculum as the control. The results demonstrate the benefits of frequent, effortful recall on student performance in a core-curriculum information technology and programming course

The Establishment of Sustainable Food Farmland Area in District of Aceh Besar

Conversion activity of paddy land to non-agricultural use of the growing opportunity to threaten national food security. One anticipation step is to set the sustainable food farming land (LPPB). This study aims to provide information about the food farming land that should be protected from the threat of conversion in the district of Aceh Besar. The approach taken is through the classification of land based on biophysicalpotency. Data obtained through survey, observation, secondary data collection, and literature studies. The study results indicate that there are four categories of paddy land, namely: the main land I (9 districts), the main land II (7 districts), the secondary land I (5 districts), and secondary land II (2 districts). The main land is the land which is suggested to be an everlasting land (sustainable) for reliable biophysical characteristics, while the secondary land could be converted as long as it is based on the main reason and more urgent

Modelling the bronchial barrier in pulmonary drug delivery: A human bronchial epithelial cell line supplemented with human tracheal mucus.

The airway epithelium together with the mucus layer coating it forms a protective system that efficiently filters and removes potentially harmful particles contained in inhaled air. The same mechanism, however, serves to entrap particulate drug carriers, precluding their interaction with their target. The mucus barrier is often neglected in in vitro testing setups employed for the assessment of pulmonary drug delivery strategies. Therefore, our aim was to more accurately model the bronchial barrier, by developing an in vitro system comprising a tight epithelial cell layer which may be optionally supplemented with a layer of human tracheal mucus. To form the epithelium in vitro, we used the cystic fibrosis cell line CFBE41o-, which can be grown as monolayers on Transwell® supports, expressing tight junctions as well as relevant transport proteins. In contrast to the cell line Calu-3, however, CFBE41o- does not produce mucus. Therefore, native human mucus, obtained from tracheal tubes of patients undergoing elective surgery, was used as a supplement. The compatibility of CFBE41o- cells with the human mucus was addressed with the MTT assay, and confirmed by fluorescein diacetate/propidium iodide live/dead staining. Moreover, the CFBE41o- cells retained their epithelial barrier properties after being supplemented with mucus, as evidenced by the high trans-epithelial electrical resistance values (∼1000Ωcm(2)) together with a continued low level of paracellular transport of sodium fluorescein. Fluorescently-labeled chitosan-coated PLGA nanoparticles (NP, ∼168nm) were used as a model drug delivery system to evaluate the suitability of this in vitro model for studying mucus permeation and cell uptake. Comparing CFBE41o- cell monolayers with and without mucus, resp., showed that the NP uptake was dramatically reduced in the presence of mucus. This model may therefore be used as a tool to study potential mucus interactions of aerosolized drugs, and more specifically NP-based drug delivery systems designed to exert their effect in the bronchial region

Short-time dynamics and magnetic critical behavior of two-dimensional random-bond Potts model

The critical behavior in the short-time dynamics for the random-bond Potts ferromagnet in two-dimensions is investigated by short-time dynamic Monte Carlo simulations. The numerical calculations show that this dynamic approach can be applied efficiently to study the scaling characteristic, which is used to estimate the critical exponents theta, beta/nu and z for the quenched disorered systems from the power-law behavior of the kth moments of magnetizations.Comment: 10 pages, 4 figures Soft Condensed Matte

Outcomes of open mitral valve replacement versus Transcatheter mitral valve repair; insight from the National Inpatient Sample Database.

Background: Transcatheter mitral valve repair and replacement (TMVR) is a minimally invasive alternative to conventional open-heart mitral valve replacement (OMVR). The present study aims to compare the burden, demographics, cost, and complications of TMVR and OMVR. Methods: The United States National Inpatient Sample (US-NIS) for the year 2017 was queried to identify all cases of TMVR and OMVR. Categorical and continuous data were analyzed using Pearson chi-square and independent t-test analysis, respectively. An adjusted odds ratio (aOR) based on the ordinal logistic regression (OLR) model was calculated to determine the association between outcome variables. Results: Of 19,580 patients, 18,460 (94%) underwent OMVR and 1120 (6%) TMVR. Mean ages of patients were 63 ± 14 years (OMVR) and 67 ± 13 years (TMVR). Both cohorts were predominantly Caucasian (73% OMVR vs. 74.0% TMVR). The patients who underwent TMVR were more likely to belong to a household with an income in the highest quartile (26.1% vs. 22.0% for OMVR) versus the lowest quartile (22.1% vs. 27.8%). The average number of days from admission to TMVR was less compared to OMVR (2.63 days vs. 3.02 days, p = 0.015). In-hospital length of stay (LOS) was significantly lower for TMVR compared to OMVR (11.56 vs. 14.01 days, p=\u3c0.0001). Adjusted in-hospital mortality taking into account comorbidities showed no significant difference between the two groups (OR 1.2, 0.93-1.68, p = 0.15). Conclusion: Patients undergoing TMVR were older and more financially affluent. TMVR was more costly but was associated with a shorter hospital stay and similar mortality to OMVR