A case of congenital hemolytic anemia caused by pyruvate kinase (PK) deficiency variant designated PK 'Nichinan' is presented. A 29-old patient with a history of anemia and hepatosplenomegaly had an episode of aplastic crisis associated with fever, abdominal symptoms and worsening hepatosplenomegaly. Study of the family members revealed that his mother and two of three siblings showed decreased PK activity whereas his father showed normal PK activity with a normal level of glycolytic intermediates. The patient was assumed to be a double heterozygote with two separate mutant genes from the parents despite the apparent normality of his father's erythrocyte PK.

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Background: Recent studies have implicated systemic inflammation in the genesis and maintenance of atrial arrhythmias. This study was designed to assess whether the inflammatory state influences the recurrence of atrial fibrillation (AF) after cardioversion for persistent AF (PerAF). Methods and Results: Twelve patients referred for cardioversion of PerAF lasting more than 2 months (mean duration: 16.8 ± 19.7 months) were included in the study. Body mass index (BMI), serum high-sensitivity C-reactive protein (hs-CRP), atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), and left ventricular ejection fraction (LVEF) were measured before cardioversion. Cardioversion was successful in all patients, but AF recurred in 7 patients (58%) during the 6-month follow-up period. There were no significant differences in age, AF duration, LVEF, or ANP or BNP levels between patients with and without recurrent AF. However, the BMI was significantly higher in the patients with recurrent AF than in those without (27.5 ± 4.0 vs. 22.3 ± 2.8, respectively, P = 0.04). The hs-CRP concentration was also significantly higher in the patients with recurrent AF compared with those without (1461 ± 1013 vs. 225 ± 77 ng/mL, respectively, P = 0.04). The left atrial diameter was also significantly greater in patients with recurrence compared with those without (48.3 ± 8.5 vs. 38.3 ± 4.1 mm, respectively, P = 0.02). Conclusion: Inflammation may contribute to the pathogenesis of AF and may be useful in identifying patients most likely to not benefit from cardioversion.

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At the final maturation process red blood cells (RBC) are enucleated, becoming unable to synthesize nucleic acids as well as proteins. RBCs survive approximately 120 days in circulation using glucose as the sole energy source. Most crucial RBC functions depend on ATP to sustain physiological homeostasis. It is thus quite important that generation of ATP by glycolysis and replenishing of adenine nucleotide pools by the reaction, which is catalyzed by adenylate kinase (AK1). In turn, ribosomal RNA is degraded during remodeling of reticulocytes, and pyrimidine ribonucleotides become unnecessary for RBC viability. Thus they should be dephosphorylated by pyrimidine 5'-nucleotidase (P5N-I) and finally transported outside RBCs. There have been reported that hereditary deficiency of AK1 and P5N-I may cause shortened RBC life span, i.e. hemolytic anemia. In this review, we summarize physiological importance of these enzymes, which are involved in ribonucleotides metabolism during RBC maturation.

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内因的ノイズは遺伝子ネットワークにおける重要な要素である。本研究では振動的な振る舞いを示す概日リズムモデルを対象に、内因的ノイズを考慮した際のモデルの評価とロバスト性解析を行う。確率的摂動を受ける周期軌道の近傍における解析に必要な全ての情報は、共分散行列方程式に含まれる。本研究では、共分散行列に基づき、軌道と周期のゆらぎを評価する手法を提案し、パラメータ変動に対する評価とロバスト性解析を行う。

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Many biological and artifact networks often represent modular structures in which the network can be decomposed into several subnetworks. Here, we propose a simple model for the modular network evolution based on the nonlinear denoising in node activities. This model suggests that modular networks can evolve under certain conditions — if the stipulated goals for the networks or the input and target output pairs involve modular features, or if the signal transfer in a node is carried out in a nonlinear manner with respect to the saturation at the upper and lower bounds. Our model highlights the positive role played by noise in modular network evolution.

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Due to vehicle movement and lossy wireless channels, providing a reliable and efficient multi-hop broadcast service in vehicular ad hoc networks (VANETs) is a well-known challenging problem. In this paper, we propose BR-NB (broadcast with neighbor information), a fuzzy logic based multi-hop broadcast protocol for VANETs. BR-NB achieves a low overhead by using only a subset of neighbor nodes to relay data packets. For the relay node selection, BR-NB jointly considers multiple metrics of the inter-vehicle distance, vehicle mobility and link quality by employing fuzzy logic. Since the expected coverage and vehicle mobility are inferred from the two-hop neighbor information which can be acquired from the hello message exchange, BR-NB is independent of position information. BR-NB provides a practical and portable solution for broadcast services in VANETs. We use computer simulations and real-world experiments to evaluate the performance of BR-NB.

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Vehicular ad hoc networks have been attracting the interest of both academic and industrial communities on account of their potential role in Intelligent Transportation Systems (ITS). However, due to vehicle movement and fading in wireless communications, providing a reliable and efficient multi-hop broadcast service in vehicular ad hoc networks is still an open research topic. In this paper, we propose FUZZBR (FUZZy BRoadcast), a fuzzy logic based multi-hop broadcast protocol for information dissemination in vehicular ad hoc networks. FUZZBR has low message overhead since it uses only a subset of neighbor nodes to relay data messages. In the relay node selection, FUZZBR jointly considers multiple metrics of inter-vehicle distance, node mobility and signal strength by employing the fuzzy logic. FUZZBR also uses a lightweight retransmission mechanism to retransmit a packet when a relay fails. We use computer simulations to evaluate the performance of FUZZBR.

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Grid forming inverters are expected to be installed in the utility grid in the near future, because they can provide inertia and short circuit capacity that are likely to decrease due to abolishment of thermal power plants. Also, these inverters have the advantage of enabling stand-alone operation for microgrid or business continuity plan. Since a conventional grid following inverter controls its output current directly, it is easy to prevent overcurrent in an event of a grid fault. On the other hand, a grid forming inverter works as a voltage source, therefore it is a challenge to limit its output current. This paper provides a low voltage ride through control method for a grid forming inverter, which is based on a virtual impedance. It realizes reliable current limitation and stable operation. The effectiveness of the proposed control method is verified by EMT simulation.

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We present a congestion control algorithm for the Internet and assess its stability. The algorithm has low operation complexity and exercises control over sources without keeping per-flow information. Given the lack of support for explicit-rate feedback in the Internet, we discuss an implementation where feedback is based on explicit binary indications. We assess the stability through a discrete-time model and present simulation results showing the efficacy of the algorithm. The obtained results indicate that when the algorithm is used to control sources that support explicit binary feedback, its stability is not affected and its performance is close to that obtained with sources that support explicit-rate feedback.

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