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Frozen pears, obtained by repeated freezing and thawing under cold outdoor conditions in winter, are very popular in northeast China. The effects of three freeze-thaw cycles (FT1-FT3) on Nanguo pear flavor were studied under fast (-80°C) and slow (-20°C) freezing conditions. Significant differences were found in the flavor of Nanguo pear after subsequent freeze-thaw cycles. The total soluble solid (TSS) content of fresh pear was 14.17 g/100 g and increased significantly after the first freeze-thaw cycle to 17.57-18.17 g/100 g. Lower TSS content was found in pears after the repeated freeze-thawing process. Citric acid was determined as the main organic acid of Nanguo pear. Its content and the overall content of organic acids decreased successively after each freezing and thawing cycle. The electronic tongue analysis results showed that the sourness of fresh pears generally decreased after their repeated freezing and thawing, that the odor of Nanguo pear changed significantly after freeze-thaw cycles, and that nitrogen oxides and hydrocarbons were the most differentiating odor compounds. The content of ethyl caproate was the highest in the volatile compound profile of the Nanguo pear and ranged from 377.26 to 526.77 µg/kg. In short, after repeated freezing and thawing, the changes in the chemical composition impart the frozen pear a unique flavor. [ABSTRACT FROM AUTHOR]

Policymakers are increasingly interested in quantifying nonprofit hospitals' tax benefits to assess whether hospitals' nonprofit status is justified. Property taxes that nonprofits would otherwise pay are among the more difficult tax benefit to quantify. This paper aims to educate stakeholders on the issues with estimating nonprofit hospitals' property tax benefits. We focus on Indiana because of relative advantages in its property tax record system. We first use a statewide database that identifies tax-exempt hospital properties to estimate property tax savings for all nonprofit hospitals in the state. We then examine five counties to quantify property tax benefits for specific hospitals. Using statewide data, we estimate a total property tax savings of $75.3 million in 2020 for all nonprofit hospitals in Indiana. However, upon closer examination of the five selected counties, we find that the state's identification code for hospital properties fails to identify over 500 property accounts associated with the nonprofit hospitals. Allowing for these additional properties increases nonprofit hospitals' tax savings in these counties by about 71%. These results suggest that our statewide estimate most likely understates nonprofit hospitals' property tax benefits by a significant amount. If statewide estimates were comparably understated, property tax savings in 2020 for all nonprofit hospitals in Indiana would be closer to $128 million. We conclude with policy recommendations. [ABSTRACT FROM AUTHOR]

Background: HIV-infected long-term non-progressor (LTNP) subjects can prevent viral replication and may harbor useful information for the development of both antibody and active vaccination treatments. In this study we used LTNP sera to examine the epitopes presented to the gp160 protein, and from this procedure we hope to elucidate potential biomarkers pertaining to the level of resistance a patient may have in developing AIDS after infection with HIV. We used five clinical sera samples from LTNP patients to identify common epitopes by ELISA; peptides with high binding to sera were selected and analyzed for conservation among HIV clades. Antibodies were generated against one identified epitope using a chimeric peptide in BALB/c mice, and both the sera from these mice and LTNP sera were tested for viral inhibition capabilities. Results: A monoclonal antibody, CL3, against one identified epitope was used to compare these epitopes neutralizing capability. LTNP sera was also studied to determine chemokine/cytokine changes in these patients. The sera from LTNP patients 2, 3, 4, and 5 were identified as having the highest titers, and also significantly inhibited syncytia formation in vitro. Finally, the protein cytokine array demonstrated that I-309 and IGFBP-1 decreased in LTNPs, but levels of TIMP-1 and NAP-2 increased significantly. Conclusions: Our results indicate that the use of LTNP samples may be a useful for identifying further anti-viral epitopes, and may be a possible predictor for determining if patients show higher resistances of converting the HIV infection to AIDS. [ABSTRACT FROM AUTHOR]

Space charge distribution and breakdown strength were investigated in composites of low density polyethylene (LDPE) and various contents of montmorillonite (MMT). The disperse performance of MMT in LDPE was observed with scanning electron microscopy (SEM) and X-ray diffraction. For MMT concentration of 1 wt%, the better intercalation of LDPE into MMT interlayers and the tighter interface structure between polymer-filler were observed, relative to MMT concentration of 3 and 5 wt%. Space charge profiles were obtained using the pulsed electroacoustic (PEA) method. Less space charge accumulated in the LDPE/MMT with MMT content of 1 wt% than that in pure LDPE, and space charge in the central of LDPE/MMT was much more uniformly. On the other hand, when MMT concentration was up to 3 and 5wt%, large amounts of hetero charges were accumulated in the sample bulk. In MMT doped samples the dielectric strength increased up to a maximum at 1wt% loading, and then decreases at 3 and 5wt%. [ABSTRACT FROM AUTHOR]

OBJECTIVES: Self-insured employers cover more people than Medicare, Medicaid, or direct purchasers of private insurance. This study examined the ability of self-insured employers to negotiate hospital prices and the relationship between hospital prices and employer market power in the United States. STUDY DESIGN: Repeated cross-section analysis of commercial claims. METHODS: We used the US Census Bureau County Business Patterns data to estimate employer market power at the metropolitan statistical area (MSA)--year level and used the Truven Health MarketScan commercial claims to estimate mean hospital prices and price ratios at the MSA-year level (2010-2016). We calculated descriptive statistics for employer market power, mean hospitalization prices, and a case mix--adjusted price ratio measure during the study period and analyzed the 10 most concentrated labor markets. We estimated MSA-year--level ordinary least squares regressions of hospitalization price and the price ratio measure on employer market power. RESULTS: Large self-insured employers had concentrated market power in very few MSAs in 2016. The mean value of our employer market power measure was 62 for 2016, compared with the mean value of 5410 for hospital market power in the United States. Regression analyses find a slight relationship: A 1-point increase in employer market power was associated with a $6.61 decrease in the hospitalization price (mean = $20,813), but this result becomes statistically insignificant once the models control for hospital wages. CONCLUSIONS: Employer market power is low in most MSAs. Self-insured employers may consider building purchase alliances with state and local government employee groups to enhance their market power and lower negotiated prices for hospital services. [ABSTRACT FROM AUTHOR]

How left-right (LR) asymmetry emerges in a patterning field along the anterior-posterior axis remains an unresolved problem in developmental biology. Left-biased Nodal emanating from the LR organizer propagates from posterior to anterior (PA) and establishes the LR pattern of the whole embryo. However, little is known about the regulatory mechanism of the PA spread of Nodal and its asymmetric activation in the forebrain. Here, we identify bilaterally expressed Follistatin (Fst) as a regulator blocking the propagation of the zebrafish Nodal ortholog Southpaw (Spaw) in the right lateral plate mesoderm (LPM), and restricting Spaw transmission in the left LPM to facilitate the establishment of a robust LR asymmetric Nodal patterning. In addition, Fst inhibits the Activin-Nodal signaling pathway in the forebrain thus preventing Nodal activation prior to the arrival, at a later time, of Spaw emanating from the left LPM. This contributes to the orderly propagation of asymmetric Nodal activation along the PA axis. The LR regulation function of Fst is further confirmed in chick and frog embryos. Overall, our results suggest that a robust LR patterning emerges by counteracting a Fst barrier formed along the PA axis. [ABSTRACT FROM AUTHOR]

Caenorhabditis elegans neurons under stress can produce giant vesicles, several microns in diameter, called exophers. Current models suggest that exophers are neuroprotective, providing a mechanism for stressed neurons to eject toxic protein aggregates and organelles. However, little is known of the fate of the exopher once it leaves the neuron. We found that exophers produced by mechanosensory neurons in C. elegans are engulfed by surrounding hypodermal skin cells and are then broken up into numerous smaller vesicles that acquire hypodermal phagosome maturation markers, with vesicular contents gradually degraded by hypodermal lysosomes. Consistent with the hypodermis acting as an exopher phagocyte, we found that exopher removal requires hypodermal actin and Arp2/3, and the hypodermal plasma membrane adjacent to newly formed exophers accumulates dynamic F-actin during budding. Efficient fission of engulfed exopher-phagosomes to produce smaller vesicles and degrade their contents requires phagosome maturation factors SAND-1/Mon1, GTPase RAB-35, the CNT-1 ARF-GAP, and microtubule motor-associated GTPase ARL-8, suggesting a close coupling of phagosome fission and phagosome maturation. Lysosome activity was required to degrade exopher contents in the hypodermis but not for exopher-phagosome resolution into smaller vesicles. Importantly, we found that GTPase ARF-6 and effector SEC-10/exocyst activity in the hypodermis, along with the CED-1 phagocytic receptor, is required for efficient production of exophers by the neuron. Our results indicate that the neuron requires specific interaction with the phagocyte for an efficient exopher response, a mechanistic feature potentially conserved with mammalian exophergenesis, and similar to neuronal pruning by phagocytic glia that influences neurodegenerative disease. [ABSTRACT FROM AUTHOR]

Centrosomal protein FOR20 has been reported to be crucial for essential cellular processes, including ciliogenesis, cell migration, and cell cycle in vertebrates. However, the function of FOR20 during mammalian embryonic development remains unknown. To investigate the in vivo function of the For20 gene in mammals, we generated For20 homozygous knockout mice by gene targeting. Our data reveal that homozygous knockout of For20 results in significant embryonic growth arrest and lethality during gestation, while the heterozygotes show no obvious defects. The absence of For20 leads to impaired left‐right patterning of embryos and reduced cilia in the embryonic node. Deletion of For20 also disrupts angiogenesis in yolk sacs and embryos. These results highlight a critical role of For20 in early mammalian embryogenesis. [ABSTRACT FROM AUTHOR]

Members of the superfamily of solute carrier (SLC) transmembrane proteins transport diverse substrates across distinct cellular membranes. Three SLC protein families transport distinct neurotransmitters into synaptic vesicles to enable synaptic transmission in the nervous system. Among them is the SLC17A6/7/8 family of vesicular glutamate transporters, which endows specific neuronal cell types with the ability to use glutamate as a neurotransmitter. The genome of the nematode Caenorhabditis elegans encodes three SLC17A6/7/8 family members, one of which, eat-4/VGLUT, has been shown to be involved in glutamatergic neurotransmission. Here, we describe our analysis of the two remaining, previously uncharacterized SLC17A6/7/8 family members, vglu-2 and vglu-3. These two genes directly neighbor one another and are the result of a recent gene duplication event in C. elegans, but not in other Caenorhabditis species. Compared to EAT-4, the VGLU-2 and VGLU-3 protein sequences display a more distant similarity to canonical, vertebrate VGLUT proteins. We tagged both genomic loci with gfp and detected no expression of vglu-3 at any stage of development in any cell type of both C. elegans sexes. In contrast, vglu-2::gfp is dynamically expressed in a restricted set of distinct cell types. Within the nervous system, vglu-2::gfp is exclusively expressed in a single interneuron class, AIA, where it localizes to vesicular structures in the soma, but not along the axon, suggesting that VGLU-2 may not be involved in synaptic transport of glutamate. Nevertheless, vglu-2 mutants are partly defective in the function of the AIA neuron in olfactory behavior. Outside the nervous system, VGLU-2 is expressed in collagen secreting skin cells where VGLU-2 most prominently localizes to early endosomes, and to a lesser degree to apical clathrin-coated pits, the trans-Golgi network, and late endosomes. On early endosomes, VGLU-2 colocalizes most strongly with the recycling promoting factor SNX-1, a retromer component. Loss of vglu-2 affects the permeability of the collagen-containing cuticle of the worm, and based on the function of a vertebrate VGLUT1 protein in osteoclasts, we speculate that vglu-2 may have a role in collagen trafficking in the skin. We conclude that C. elegans SLC17A6/7/8 family members have diverse functions within and outside the nervous system. [ABSTRACT FROM AUTHOR]

Background: As the most populous nation in the world, China has now becoming an emerging ageing society. Shanghai is the first city facing the challenge of ageing demographics. Against this background, a study that employs self-rated health (SRH) assessment system was designed to explore the health status of Shanghai elders, and learn their attitudes toward health issues; as well as to investigate the determinants of SRH among Shanghai elders. Understanding SRH is crucial for finding appropriate solutions that could effectively tackle the increasing eldercare demand.Methods: This study adopted a quantitative research strategy. Using a multistage stratified cluster sampling method, we conducted a questionnaire survey in August 2011 in Shanghai, which collected 2001 valid survey responses. SRH assessments were categorized by five levels: very good, fairly good, average, fairly poor, or poor. The respondents' functional status was evaluated using the Barthel index of activities for daily living. In the data analysis, we used chi-squared test to determine differences in socio-demographic characteristics among various groups. Along with statistics, several logistic regression models were designed to determine the associations between internal influence factors and SRH.Results: Younger age (χ2 = 27.5, p < 0.05), male sex (χ2 = 11.5, p < 0.1), and living in the suburbs (χ2 = 55.1, p < 0.05) were associated with better SRH scores. Higher SRH scores were also linked with health behaviour of the respondents; namely, do not smoke (χ2 = 18.0, p < 0.1), do not drink (χ2 = 18.6, p < 0.1), or engage in regular outdoor activities (χ2 = 69.3, p < 0.05). The respondents with better social support report higher SRH scores than those without. Respondents' ability to hear (χ2 = 38.7, p < 0.05), speak (χ2 = 16.1, p < 0.05) and see (χ2 = 78.3, p < 0.05) impacted their SRH scores as well. Meanwhile, chronic illness except asthma was a major influence factor in low SRH score. Applying multiple regression models, a series of determinants were analysed to establish the extent to which they contribute to SRH. The impact of these variables on SRH scores were 6.6% from socio-demographic and health risk behaviours, 2.4% from social support, 8.5% from mental health, 20% from physical conditions, and13% from chronic diseases.Conclusions: This is the first study that examines the determinants of SRH among Shanghai elders. Nearly 40% of our study's respondents reported their health status as "good". The main determinants of SRH among elders include living condition, health risk behaviour, social support, health status, and the economic status of the neighbourhood. [ABSTRACT FROM AUTHOR]

DNA methylation is an important epigenetic mark in many eukaryotic organisms. De novo DNA methylation in plants can be achieved by the RNA-directed DNA methylation (RdDM) pathway, where the plant-specific DNA-dependent RNA polymerase IV (Pol IV) transcribes target sequences to initiate 24-nt siRNA production and action. The putative DNA binding protein DTF1/SHH1 of Arabidopsis has been shown to associate with Pol IV and is required for 24-nt siRNA accumulation and transcriptional silencing at several RdDM target loci. However, the extent and mechanism of DTF1 function in RdDM is unclear. We show here that DTF1 is necessary for the accumulation of the majority of Pol IV-dependent 24-nt siRNAs. It is also required for a large proportion of Pol IV-dependent de novo DNA methylation. Interestingly, there is a group of RdDM target loci where 24-nt siRNA accumulation but not DNA methylation is dependent on DTF1. DTF1 interacts directly with the chromatin remodeling protein CLASSY 1 (CLSY1), and both DTF1 and CLSY1 are associated in vivo with Pol IV but not Pol V, which functions downstream in the RdDM effector complex. DTF1 and DTF2 (a DTF1-like protein) contain a SAWADEE domain, which was found to bind specifically to histone H3 containing H3K9 methylation. Taken together, our results show that DTF1 is a core component of the RdDM pathway, and suggest that DTF1 interacts with CLSY1 to assist in the recruitment of Pol IV to RdDM target loci where H3K9 methylation may be an important feature. Our results also suggest the involvement of DTF1 in an important negative feedback mechanism for DNA methylation at some RdDM target loci. [ABSTRACT FROM AUTHOR]

Proliferation of the neural/neuronal progenitor cells (NPCs) at the ventricular zone of the dorsal spinal cord requires the stimuli of Wnt and bone morphogenic protein (BMP). However, how these two signaling pathways are regulated to initiate differentiation in the NPCs as they enter the intermediate zone is not known. Here, we show that Smad6, a negative regulator of BMP signaling, is expressed in the intermediate zone of the chick dorsal spinal cord. Knockdown experiments show that Smad6 is required for promoting NPCs to exit the cell cycle and differentiate into neurons. Although we find that Smad6 inhibits BMP signaling, as expected, we also find that Smad6 unexpectedly inhibits the Wnt/β-catenin pathway. The inhibition of the Wnt/β-catenin pathway by Smad6 is independent of its effect on the BMP pathway. Rather, Smad6 through its N-terminal domain and link region enhances the interaction of C-terminal binding protein with the β-catenin/T cell factor (TCF) complex and the TCF-binding element to inhibit β-catenin-mediated transcriptional activation. Our study provides evidence that transition of NPCs from a proliferative state to a differentiating state is controlled by the dual inhibitory role of Smad6 to both BMP and Wnt signaling at the level of transcription. [ABSTRACT FROM AUTHOR]