Genetic Parameter Estimation in Seedstock Swine Population for Growth Performances

The objective of this study was to estimate genetic parameters that are to be used for across-herd genetic evaluations of seed stock pigs at GGP level. Performance data with pedigree information collected from swine breeder farms in Korea were provided by Korea Animal Improvement Association (AIAK). Performance data were composed of final body weights at test days and ultrasound measures of back fat thickness (BF), rib eye area (EMA) and retail cut percentage (RCP). Breeds of swine tested were Landrace, Yorkshire and Duroc. Days to 90 kg body weight (DAYS90) were estimated with linear function of age and ADG calculated from body weights at test days. Ultrasound measures were taken with A-mode ultrasound scanners by trained technicians. Number of performance records after censoring outliers and keeping records pigs only born from year 2000 were of 78,068 Duroc pigs, 101,821 Landrace pigs and 281,421 Yorkshire pigs. Models included contemporary groups defined by the same herd and the same seasons of births of the same year, which was regarded as fixed along with the effect of sex for all traits and body weight at test day as a linear covariate for ultrasound measures. REML estimation was processed with REMLF90 program. Heritability estimates were 0.40, 0.32, 0.21 0.39 for DAYS90, ADG, BF, EMA, RCP, respectively for Duroc population. Respective heritability estimates for Landrace population were 0.43, 0.41, 0.22, and 0.43 and for Yorkshire population were 0.36, 0.38, 0.22, and 0.42. Genetic correlation coefficients of DAYS90 with BF, EMA, or RCP were estimated to be 0.00 to 0.09, −0.15 to −0.25, 0.22 to 0.28, respectively for three breeds populations. Genetic correlation coefficients estimated between BF and EMA was −0.33 to −0.39. Genetic correlation coefficient estimated between BF and RCP was high and negative (−0.78 to −0.85) but the environmental correlation coefficients between these two traits was medium and negative (near −0.35), which describes a highly correlated genetic response to selection on one or the other of these traits. Genetic Trends of all three breeds tend to be towards bigger EMA or greater RCP and shorter DAYS90 especially from generations born after year 2000

Effects of transcranial ultrasound stimulation pulsed at 40 Hz on A beta plaques and brain rhythms in 5xFAD mice

Background: Alzheimer’s disease (AD) is the most common cause of dementia, and is characterized by amyloid-β (Aβ) plaques and tauopathy. Reducing Aβ has been considered a major AD treatment strategy in pharmacological and non-pharmacological approaches. Impairment of gamma oscillations, which play an important role in perception and cognitive function, has been shown in mouse AD models and human patients. Recently, the therapeutic effect of gamma entrainment in AD mouse models has been reported. Given that ultrasound is an emerging neuromodulation modality, we investigated the effect of ultrasound stimulation pulsed at gamma frequency (40 Hz) in an AD mouse model. Methods: We implanted electroencephalogram (EEG) electrodes and a piezo-ceramic disc ultrasound transducer on the skull surface of 6-month-old 5×FAD and wild-type control mice (n = 12 and 6, respectively). Six 5×FAD mice were treated with two-hour ultrasound stimulation at 40 Hz daily for two weeks, and the other six mice received sham treatment. Soluble and insoluble Aβ levels in the brain were measured by enzyme-linked immunosorbent assay. Spontaneous EEG gamma power was computed by wavelet analysis, and the brain connectivity was examined with phase-locking value and cross-frequency phase-amplitude coupling. Results: We found that the total Aβ42 levels, especially insoluble Aβ42, in the treatment group decreased in pre- and infra-limbic cortex (PIL) compared to that of the sham treatment group. A reduction in the number of Aβ plaques was also observed in the hippocampus. There was no increase in microbleeding in the transcranial ultrasound stimulation (tUS) group. In addition, the length and number of microglial processes decreased in PIL and hippocampus. Encelphalographic spontaneous gamma power was increased, and cross-frequency coupling was normalized, implying functional improvement after tUS stimulation. Conclusion: These results suggest that the transcranial ultrasound-based gamma-band entrainment technique can be an effective therapy for AD by reducing the Aβ load and improving brain connectivity. © 2021, The Author(s).1

Reversibly controlled ternary polar states and ferroelectric bias promoted by boosting square???tensile???strain

Interaction between dipoles often emerges intriguing physical phenomena, such as exchange bias in the magnetic heterostructures and magnetoelectric effect in multiferroics, which lead to advances in multifunctional heterostructures. However, the defect-dipole tends to be considered the undesired to deteriorate the electronic functionality. Here, we report deterministic switching between the ferroelectric and the pinched states by exploiting a new substrate of cubic perovskite, BaZrO3, which boosts square-tensile-strain to BaTiO3 and promotes four-variants in-plane spontaneous polarization with oxygen vacancy creation. First-principles calculations propose a complex of an oxygen vacancy and two Ti3+ ions coins a charge-neutral defect-dipole. Cooperative control of the defect-dipole and the spontaneous polarization reveals ternary in-plane polar states characterized by biased/pinched hysteresis loops. Furthermore, we experimentally demonstrate that three electrically controlled polar-ordering states lead to switchable and non-volatile dielectric states for application of non-destructive electro-dielectric memory. This discovery opens a new route to develop functional materials via manipulating defect-dipoles and offers a novel platform to advance heteroepitaxy beyond the prevalent perovskite substrates

Morphological Structure of Silica Sulfuric Acid and Nafion Composite Membrane Using Electrostatic Force Microscopy

In this study, the proton conductivity enhancement mechanism of Nafion–silica sulfuric acid (SSA) composite membranes was studied using the vibrating tip technique of atomic force microscopy. The Nafion–SSA composite membranes showed enhanced proton conductivity and thermal and mechanical properties compared to those of pristine Nafion. Among the selected different weight percentages of SSA, 1 wt% SSA had the highest values. The aim of this study was to understand how proton conductivity enhancement is related to structure and morphology. It was determined that the enhancement is related to a microscopic morphological structure, which is the separation of the hydrophilic ionic channel network and hydrophobic backbone. The morphologies of membranes of three different weight percentages were studied using non-contact mode atomic force microscopy, force-distance spectroscopy, and electrostatic force microscopy to understand the ionic domain structures. Several factors that influence the proton conductivity enhancement of the composite membranes were investigated, including water content, hydrophilicity, and ionic domain enhancement due to the interconnection of the silica sulfuric acid (SSA) and ionomer. Among the different SSA weight percentages, the 1 wt% Nafion–SSA composite membrane demonstrated superior performance. It presented the highest energy dissipation, water content, and phase separation. This result implied that 1 wt% SSA optimally induced phase separation owing to the interaction with the sulfonic acid groups of the SSA and reorganization of the morphological structure compared with other weight percentages of Nafion–SSA composite membranes.1

Receptor-mediated gene delivery into antigen presenting cells using mannosylated chitosan/DNA nanoparticles

Dendritic cells (DCs) are professional antigen presenting cells that induce, sustain, and regulate immune responses. Gene modification of DCs is of particular interest for immunotherapy of diseases where the immunes system has failed or is abnormally regulated, such as in cancer or autoimmune disease. Gene transfer using non-viral vectors is a promising approach for the safe delivery of therapeutic DNA. Among various non-viral vectors, chitosan is considered to be a good candidate for gene delivery system, however, lack of cell specificity and low transfection of chitosan need to be overcome prior to clinical use. In this study, mannosylated chitosan (MC) was prepared to induce the receptor-mediated endocytosis and targeting into antigen presenting cells (APCs), especially DCs having mannose receptors. MC showed great ability to form complexes with DNA and showed suitable physicochemical properties for gene delivery system. It had low cytotoxicity and exhibited much enhanced gene transfer efficiency on the macrophage cell line than chitosan itself. Also, MC/DNA complex was more efficient for transferring IL-12 gene into DCs rather than water-soluble chitosan (WSC)/DNA one, which resulted in better induction of INF-gamma from DCs. Therefore, MC is a promising gene delivery system for repeated administration to maintain sustained gene expression, thereby opening the possibility for immunotherapy

Controlled release of plasmid DNA from photo-cross-linked pluronic hydrogels

Chemically cross-linked hydrogels composed of PluronicTM, water-soluble tri-block copolymers of poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide), were synthesized by a photo-polymerization method to achieve controlled DNA release. Pluronic F127 was di-acrylated to form a macromer and cross-linked to form a hydrogel structure in the presence and absence of vinyl group-modified hyaluronic acid (HA). UV irradiation time and the presence of the vinyl group-modified HA affected the mechanical property of Pluronic hydrogels to a great extent. Swelling ratio, degradation, and rheological behaviors of Pluronic hydrogels were investigated. When plasmid DNA was loaded in the hydrogels for sustained delivery, various release profiles were attained by varying UV irradiation time and modified HA amounts. Entrapped DNA was gradually damaged with increasing the UV exposure time as evidenced by decreasing the transfection efficiency. The DNA fractions released from the HA/Pluronic hydrogels, however, exhibited considerable transfection efficiencies commensurate with the UV exposure time, suggesting that they were not chemically degraded during the release period and substantially maintained functional gene expression activities despite the UV irradiation.NRC publication: N