Enhanced antigen presentation and immunostimulation of dendritic cells using acid-degradable cationic nanoparticles.

Acid-degradable cationic nanoparticles encapsulating a model antigen (i.e., ovalbumin) were prepared by inverse microemulsion polymerization with acid-cleavable acetal cross-linkers. Incubation of these degradable nanoparticles with dendritic cells derived from bone marrow (BMDCs) resulted in the enhanced presentation of ovalbumin-derived peptides, as quantified by B3Z cells, a CD8+ T cell hybridoma. The cationic nature of the particles contributed to the increased surface endocytosis (or phagocytosis) observed with BMDCs, which is the first barrier to overcome for successful antigen delivery. The acid sensitivity of the particles served to direct more ovalbumin antigens to be processed into the appropriately trimmed peptide fragments and presented via the major histocompatibility complex (MHC) class I pathway following hydrolysis within the acidic lysosomes. It was also shown that adjuvant molecules such as unmethylated CpG oligonucleotides (CpG ODN) and anti-interleukin-10 oligonucleotides (AS10 ODN) could be co-delivered with the protein antigen for maximized cellular immune response

Variables Associated with Thermal Emittance of Wall Mural Art in Richmond, Virginia

The objectives of this research are to determine the factors associated with the minimum, maximum, and average thermal emittance temperatures of wall murals in Richmond, Virginia, and make recommendations for color and location of wall murals. Data for 17 parameters were collected for 64 art murals in downtown Richmond, VA from 28 June 2018 – 19 July 2018. Date, time, solar exposure duration, solar elevation, latitude, longitude, air temperature (C), lux, color, solar cardinal minutes, cardinal direction, minimum, maximum, and average surface thermal emittance temperatures of mural face were recorded for each mural. We reject the hypothesis that minimum, maximum, and average thermal emittance temperatures of wall murals do not vary significantly with temporal, spatial, physical changes, and solar factors. Maximum, minimum, and average emittance temperatures of wall mural art varied significantly with the number of minutes that solar energy directly illuminating mural art for each cardinal direction, lux, solar elevation, total diurnal exposure, maximum mural color, and percent dark colors on murals. Minimum mural wall art temperatures (30.0-37.0 C) occurred on surfaces facing East, North, Northwest, and Northeast which also had the lowest lux values (8,867-14,231); highest temperatures (44.8-49.9 C) were recorded on walls facing South, Southeast, and West, which had the highest lux values (42,517-46,000). Based on results of this study and those investigating mitigation of the urban heat island effect with building materials and coatings on walls and roofs, we recommend a study that uses a systematic approach to locating wall mural art based on specific colors, paint composition, and wall materials to guide local building authorities owners, and artists to maximize albedo. Additionally, we recommend, where possible, mural art should be painted on vertical surfaces facing North, Northeast, and Northwest where lux values and thermal gain are the lowest of all possible cardinal directions. Such locations could accommodate the use of dark colors without significantly increasing the heat load in urban communities. And finally, where mural art is being considered for building walls facing South, Southeast, Southwest and West, we recommend that artists use a palette of primarily light colors with high reflective properties to maximize albedo, and minimize use of dark colors

A Role of Glutathione-Encoding Gene (gshA) in Oxidative Stress and Antibiotic Susceptibility in Multidrug Resistant Pseudomonas aeruginosa: A Possible Drug Target

Background: Pseudomonas aeruginosa is a major causative agent of hospital- and community-acquired infections. Antibacterial treatment of the infections is often difficult due to presence of antibiotic resistant P. aeruginosa. A number of intrinsic and acquired antibiotic resistance mechanisms reported in P. aeruginosa. Recently, scavenging intracellular reactive oxygen species (ROS) has suggested as an intrinsic antibiotic resistance mechanism to all bacterial species since antibiotics induce oxidative stress in the bacterial species. However, this intrinsic resistance mechanism is currently controversial and further clarification requires. Glutathione is a sulfuhydryl (-SH)-containing tri-peptide intracellular antioxidant and serves as a scavenger of the intracellular ROS. Aim: In this study, a mutant P. aeruginosa knocked-out a gene (gshA) encoding glutathione synthetase, a gshA-complemented mutant P. aeruginosa, and their parental wild type (MPAO1) used to understand the role of glutathione in the neutralization of oxidative stress (H2O2) and antibiotic susceptibility. Approaches and Results: Bacterial killing assays showed that the mutant strain (gshA::Tn-Tc) was completely killed at 0.005% of H2O2 while the gshA-complemented and their parental strains were both completely killed at 0.01% of H2O2. Antibiotic susceptibility testing showed that the mutant strain was at least 2-fold more susceptible to all tested antibiotics than that of its parental strain. The gshA-complemented strain fully restored the susceptibility to the same antibiotics as the same levels of the parental strain. Conclusions and Discussion: The results indicate that i) glutathione is associated with neutralization of oxidative stress, ii) antibiotics induce the oxidative stress, and iii) the antibiotic-induced oxidative stress in the mutant strain may have more ROS than its parental strain which results in the increased-susceptibility to antibiotics. Overall, the results suggest that glutathione is one of the intrinsic antibiotic resistance mechanisms and may be a possible drug target to treat the untreatable multidrug resistant P. aeruginosa

Calibration of Load and Resistance Factors in LRFD Foundation Design Specifications

This report summarizes the findings and recommendations on the impact of foundation settlements on the reliability of bridge superstructures. As a collaborative effort of an overall initiative for the development of LRFD foundation design specifications, this study is focused on the investigatio of pros and cons for including foundation settlements in bridge designs under gravity loads. Settlement was modeled both probabilistically and deterministically. In the case of a random settlement variable, a lognormal distribution was used in reliability analysis with a fixed coefficient of variation of 0.25. Dead and live loads were modeled as random variables with normal and Gumbel Type I distributions, respectively. Considering the regional traffic condition on Missouri roadways, the effect of a live load reduction factor on bridge reliability was also investigated. Therefore, a total of eight cases were discussed with a complete combination of settlement modeling (mean and extreme values), design consideration (settlements included and excluded), and live load reduction (unreduced and reduced live loads). Based on extensive simulations on multi-span bridges, bridges designed without due consideration on settlements can tolerate an extreme settlement of L/3500 - L/450 under unreduced live loads and up to L/3500 under reduced live loads without resulting in a reliability index below 3.5 (L=span length). Depending upon span lengths and their ratio, the reliability of existing steel-girder bridges is consistently higher than prestressed concrete and solid slab bridges. The shorter and stiffer the spans, the more significant the settlement\u27s effect on the reliability of bridge superstructures. As the span length ratio becomes less than 0.75, the girder and solid slab bridges\u27 reliability drops significantly at small settlements. A concrete diaphragm is very susceptible to the differential settlement of bridges, particularly for moment effects. Two recommended were made to address settlement effects in bridge design: (1) settlement is considered in structural design and no special requirement is needed for foundation designs unless settlement exceeds the AASHTO recommended settlement limit of L/250, and (2) settlement is not considered in structural design as in the current MoDOT practice but ensured below the tolerable settlement (e.g. L/450 for steel girders, L/2500 for slabs, and L/3500 for prestressed concrete girders). The first method provides a direct approach to deal with settlements and has potential to reduce overall costs in bridge design. The second method may result in oversized foundations

Electromyographic Comparison Between the Rear-Foot-Elevated vs. B-Stance Unilateral Back Squat Techniques

The Rear-Foot-Elevated back squat (RFE) and B-Stance (BS) are two unilateral back squat techniques with the latter commonly proposed as the more stable of the two. There is currently a lack of research comparing these two techniques with respect to neuromuscular demand and movement characteristics. PURPOSE: The purpose of this study was to examine the muscle activation differences via surface electromyography (EMG) between the RFE vs. BS unilateral back squat techniques with equated load. METHODS: Thirteen healthy college-aged, resistance-trained male (n=10) and female (n=3) subjects were recruited for this study. Subjects visited the laboratory on two occasions separated by 5-7 days. Visit 1 included descriptive measurements and one-repetition max (1RM) testing for the RFE back squat. For visit 2, subjects performed the RFE and BS unilateral squat techniques under a load of 85% of RFE 1RM. Electromyographic assessment of the external oblique (OBL), rectus femoris (RF), gluteus maximums (GM) and biceps femoris (BF) was administered during each technique and subsequently compared. RESULTS: A paired sample t-test was used to compare mean and peak normalized root mean square (RMS) EMG between the RFE and BS techniques. There was no significant difference in mean and peak eccentric, concentric, and total activation between the RFE vs. BS for the OBL and RF. For GM, mean and peak eccentric, concentric, and total activation was greater during the RFE vs. BS (pCONCLUSION: The RFE unilateral back squat technique elicited overall greater activation of the hip extensors, GM and BF vs. BS. Based on these findings, the two unilateral squat techniques are not interchangeable from a muscle activation perspective which should be considered when employing unilateral back squat variations in training or rehabilitation programs

High-Performance Screen-Printed Thermoelectric Films on Fabrics.

Printing techniques could offer a scalable approach to fabricate thermoelectric (TE) devices on flexible substrates for power generation used in wearable devices and personalized thermo-regulation. However, typical printing processes need a large concentration of binder additives, which often render a detrimental effect on electrical transport of the printed TE layers. Here, we report scalable screen-printing of TE layers on flexible fiber glass fabrics, by rationally optimizing the printing inks consisting of TE particles (p-type Bi0.5Sb1.5Te3 or n-type Bi2Te2.7Se0.3), binders, and organic solvents. We identified a suitable binder additive, methyl cellulose, which offers suitable viscosity for printability at a very small concentration (0.45-0.60 wt.%), thus minimizing its negative impact on electrical transport. Following printing, the binders were subsequently burnt off via sintering and hot pressing. We found that the nanoscale defects left behind after the binder burnt off became effective phonon scattering centers, leading to low lattice thermal conductivity in the printed n-type material. With the high electrical conductivity and low thermal conductivity, the screen-printed TE layers showed high room-temperature ZT values of 0.65 and 0.81 for p-type and n-type, respectively

Serum 25-hydroxy vitamin D and the risk of low muscle mass in young and middle-aged Korean adults

Objective: Despite the known benefit of vitamin D in reducing sarcopenia risk in older adults, its effect against muscle loss in the young population is unknown. We aimed to examine the association of serum 25-hydroxy vitamin D [25(OH)D] level and its changes over time with the risk of incident low muscle mass (LMM) in young and middle-aged adults.Design: This study is a cohort study.Methods: The study included Korean adults (median age: 36.9 years) without LMM at baseline followed up for a median of 3.9 years (maximum: 7.3 years). LMM was defined as the appendicular skeletal muscle (ASM) mass by body weight (ASM/weight) of 1 s.d. below the sex-specific mean for the young reference group. Cox proportional hazard models were used to estimate hazard ratios (HRs) with 95% CIs.Results: Of the 192,908 individuals without LMM at baseline, 19,526 developed LMM. After adjusting for potential confounders, the multivariable-adjusted HRs (95% CIs) for incident LMM comparing 25(OH)D levels of 25-&lt;50, 50-&lt;75, and ≥75 nmol/L to 25(OH)D &lt;25 nmol/L were 0.93 (0.90-0.97), 0.85 (0.81-0.89), and 0.77 (0.71-0.83), respectively. The inverse association of 25(OH)D with incident LMM was consistently observed in young (aged &lt;40 years) and older individuals (aged ≥40 years). Individuals with increased 25(OH)D levels (&lt;50-≥50 nmol/L) or persistently adequate 25(OH)D levels (≥50 nmol/L) between baseline and follow-up visit had a lower risk of incident LMM than those with persistently low 25(OH)D levels.Conclusions: Maintaining sufficient serum 25(OH)D could prevent unfavourable changes in muscle mass in both young and middle-aged Korean adults.</p