The r-Process in Supersonic Neutrino-Driven Winds: The Roll of Wind Termination Shock

Recent hydrodynamic studies of core-collapse supernovae imply that the neutrino-heated ejecta from a nascent neutron star develops to supersonic outflows. These supersonic winds are influenced by the reverse shock from the preceding supernova ejecta, forming the wind termination shock. We investigate the effects of the termination shock in neutrino-driven winds and its roll on the r-process. Supersonic outflows are calculated with a semi-analytic neutrino-driven wind model. Subsequent termination-shocked, subsonic outflows are obtained by applying the Rankine-Hugoniot relations. We find a couple of effects that can be relevant for the r-process. First is the sudden slowdown of the temperature decrease by the wind termination. Second is the entropy jump by termination-shock heating, up to several 100NAk. Nucleosynthesis calculations in the obtained winds are performed to examine these effects on the r-process. We find that 1) the slowdown of the temperature decrease plays a decisive roll to determine the r-process abundance curves. This is due to the strong dependences of the nucleosynthetic path on the temperature during the r-process freezeout phase. Our results suggest that only the termination-shocked winds with relatively small shock radii (~500km) are relevant for the bulk of the solar r-process abundances (A~100-180). The heaviest part in the solar r-process curve (A~180-200), however, can be reproduced both in shocked and unshocked winds. These results may help to constrain the mass range of supernova progenitors relevant for the r-process. We find, on the other hand, 2) negligible roles of the entropy jump on the r-process. This is a consequence that the sizable entropy increase takes place only at a large shock radius (~10,000km) where the r-process has already ceased.Comment: 11 pages, 7 figures, submitted to ApJ, revised following referee's comments,Accepted for publication in Ap

Token Economy–Based Hospital Bed Allocation to Mitigate Information Asymmetry: Proof-of-Concept Study Through Simulation Implementation

[Background:] Hospital bed management is an important resource allocation task in hospital management, but currently, it is a challenging task. However, acquiring an optimal solution is also difficult because intraorganizational information asymmetry exists. Signaling, as defined in the fields of economics, can be used to mitigate this problem. [Objective:] We aimed to develop an assignment process that is based on a token economy as signaling intermediary. [Methods:] We implemented a game-like simulation, representing token economy–based bed assignments, in which 3 players act as ward managers of 3 inpatient wards (1 each). As a preliminary evaluation, we recruited 9 nurse managers to play and then participate in a survey about qualitative perceptions for current and proposed methods (7-point Likert scale). We also asked them about preferred rewards for collected tokens. In addition, we quantitatively recorded participant pricing behavior. [Results:] Participants scored the token economy–method positively in staff satisfaction (3.89 points vs 2.67 points) and patient safety (4.38 points vs 3.50 points) compared to the current method, but they scored the proposed method negatively for managerial rivalry, staff employee development, and benefit for patients. The majority of participants (7 out of 9) listed human resources as the preferred reward for tokens. There were slight associations between workload information and pricing. [Conclusions:] Survey results indicate that the proposed method can improve staff satisfaction and patient safety by increasing the decision-making autonomy of staff but may also increase managerial rivalry, as expected from existing criticism for decentralized decision-making. Participant behavior indicated that token-based pricing can act as a signaling intermediary. Given responses related to rewards, a token system that is designed to incorporate human resource allocation is a promising method. Based on aforementioned discussion, we concluded that a token economy–based bed allocation system has the potential to be an optimal method by mitigating information asymmetry

UCP1-dependent and UCP1-independent metabolic changes induced by acute cold exposure in brown adipose tissue of mice

Background: Brown adipose tissue (BAT) is a site of metabolic thermogenesis mediated by mitochondrial uncoupling protein 1 (UCP1) and represents a target for a therapeutic intervention in obesity. Cold exposure activates UCP1-mediated thermogenesis in BAT and causes drastic changes in glucose, lipid, and amino acid metabolism; however, the relationship between these metabolic changes and UCP1-mediated thermogenesis is not fully understood. Methods: We conducted metabolomic and GeneChip array analyses of BAT after 4-h exposure to cold temperature (10 °C) in wild-type (WT) and UCP1-KO mice. Results: Cold exposure largely increased metabolites of the glycolysis pathway and lactic acid levels in WT, but not in UCP1-KO, mice, indicating that aerobic glycolysis is enhanced as a consequence of UCP1-mediated thermogenesis. GeneChip array analysis of BAT revealed that there were 2865 genes upregulated by cold exposure in WT mice, and 838 of these were upregulated and 74 were downregulated in UCP1-KO mice. Pathway analysis revealed the enrichment of genes involved in fatty acid (FA) β oxidation and triglyceride (TG) synthesis in both WT and UCP1-KO mice, suggesting that these metabolic pathways were enhanced by cold exposure independently of UCP1-mediated thermogenesis. FA and cholesterol biosynthesis pathways were enhanced only in UCP1-KO mice. Cold exposure also significantly increased the BAT content of proline, tryptophan, and phenylalanine amino acids in both WT and UCP1-KO mice. In WT mice, cold exposure significantly increased glutamine content and enhanced the expression of genes related to glutamine metabolism. Surprisingly, aspartate was almost completely depleted after cold exposure in UCP1-KO mice. Gene expression analysis suggested that aspartate was actively utilized after cold exposure both in WT and UCP1-KO mice, but it was replenished from intracellular N-acetyl-aspartate in WT mice. Conclusions: These results revealed that cold exposure induces UCP1-mediated thermogenesis-dependent glucose utilization and UCP1-independent active lipid metabolism in BAT. In addition, cold exposure largely affects amino acid metabolism in BAT, especially UCP1-dependently enhances glutamine utilization. These results contribute a comprehensive understanding of UCP1-mediated thermogenesis-dependent and thermogenesis-independent metabolism in BAT

Pathogenic Epitopes of Autoantibodies in Pemphigus Reside in the Amino-Terminal Adhesive Region of Desmogleins Which Are Unmasked by Proteolytic Processing of Prosequence

Pemphigus targets desmogleins (Dsgs), which are thought to be synthesized as inactive precursor proteins with prosequences that are cleaved by substilisin-like proprotein convertases, such as furin, to yield mature adhesive molecules. We hypothesized that some pemphigus pathogenic antibodies (Abs), which presumably interfere with adhesion, only bind the mature form. A pathogenic and three non-pathogenic anti-Dsg1 monoclonal Abs (mAbs) isolated from a pemphigus foliaceus (PF) patient, were used for immunoprecipitation and ELISA of recombinant precursor and mature Dsg1. The pathogenic Ab binds mature Dsg1, whereas non-pathogenic Abs bind either only the precursor or both the precursor and mature Dsg1. Competition ELISA showed that the majority of PF sera target the same or nearby epitopes defined by the pathogenic anti-Dsg1 mAb that blocked >20% binding of 29 out of 40 PF sera. Furthermore, the immunoreactivity of 45 PF sera against the mature Dsg1 was 3.2 fold stronger than that against the precursor Dsg1 by ELISA. Similar results were observed in anti-Dsg3 Abs in 47 pemphigus vulgaris sera, suggesting that most pemphigus sera target epitopes that are unmasked by proteolytic processing. These findings support the idea that at least some pathogenic pemphigus autoantibodies induce the loss of cell adhesion by directly binding the trans-interaction site of Dsgs

Neuroendocrine Carcinoma of the Stomach: A Case Study

Gastric neuroendocrine carcinomas are rare and have a poor prognosis, and the diagnostic criteria for this disease have recently changed. We herein report a case of sporadic gastric neuroendocrine carcinoma. A 75-year-old man was referred to our hospital with epigastric pain. Endoscopic examination revealed a localized ulcerative lesion (diameter, 4 cm) at the upper stomach. The diagnosis on biopsy was neuroendocrine carcinoma. Total gastrectomy with D2 lymphadenectomy, splenectomy, and cholecystectomy was performed. Pathologically, the tumor infiltrated the subserosal layer, and 6/49 lymph nodes were involved. The tumor was uniform in shape and arranged in a rosette-like structure to form solid nests, with medium-sized, round-to-cuboid-shaped tumor cells and intense mitosis 46/10 HPF. It was positive for synaptophysin and chromogranin A, and the Ki-67 labeling index was 70–80%. The diagnosis of neuroendocrine carcinoma was made according to the WHO 2010 criteria. The patient was followed up for three years without recurrence

A Sub-mW MPEG-4 Motion Estimation Processor Core for Mobile Video Application

This paper describes a sub-mW motion estimation processor core for MPEG-4 video encoding. It features a gradient descent search (GDS) algorithm that reduces required computational complexity to 15 MOPS. The GDS algorithm combined with a sub-block search method upgrades picture quality. The quality is almost equal to that of a full search method. An SIMD datapath architecture optimized for the algorithm decreases a clock frequency and supply voltage. A dedicated three-port SRAM macro for image data caches of the processor is newly designed to reduce power consumption. It has been fabricated with 0.18-/spl mu/m five-layer metal CMOS technology. The VLSI processing QCIF 15-f/s video consumes 0.4-mW power at 0.85-MHz clock frequency with 1.0-V supply voltage. It is applicable to mobile video applications