Enumerating All Subgraphs Under Given Constraints Using Zero-Suppressed Sentential Decision Diagrams

Subgraph enumeration is a fundamental task in computer science. Since the number of subgraphs can be large, some enumeration algorithms exploit compressed representations for efficiency. One such representation is the Zero-suppressed Binary Decision Diagram (ZDD). ZDDs can represent the set of subgraphs compactly and support several poly-time queries, such as counting and random sampling. Researchers have proposed efficient algorithms to construct ZDDs representing the set of subgraphs under several constraints, which yield fruitful results in many applications. Recently, Zero-suppressed Sentential Decision Diagrams (ZSDDs) have been proposed as variants of ZDDs. ZSDDs can be smaller than ZDDs when representing the same set of subgraphs. However, efficient algorithms to construct ZSDDs are known only for specific types of subgraphs: matchings and paths. We propose a novel framework to construct ZSDDs representing sets of subgraphs under given constraints. Using our framework, we can construct ZSDDs representing several sets of subgraphs such as matchings, paths, cycles, and spanning trees. We show the bound of sizes of constructed ZSDDs by the branch-width of the input graph, which is smaller than that of ZDDs by the path-width. Experiments show that our methods can construct ZSDDs faster than ZDDs and that the constructed ZSDDs are smaller than ZDDs when representing the same set of subgraphs

Magnetic coupling at interface of ultrathin Co film and antiferromagnetic Cr₂O₃ (0001) film

The magnetic coupling at the interface of Co and Cr has been investigated using ultrathin Co film on Cr₂O₃ (0001) film, which is expected to be a promising system to show the magnetoelectronic effect. We mainly examined the temperature dependence of magnetization, the exchange bias at different field directions relative to the Cr spin direction, and the temperature dependence of exchange bias. The temperature dependence of magnetization under 50 Oe indicates the collinear coupling of Co spin and Cr spin at the interface. Furthermore, the exchange bias effect is observed in the coupled direction of Co and Cr, namely, parallel to the Cr spin direction. However, the changes in the magnetic behavior with changing field directions and Co thicknesses imply the existence of biquadratic coupling of Co spin and Cr spin, as well. In agreement with the numerical calculation under the coexistence of collinear and biquadratic couplings, the exchange bias field decreases nonmonotonically with increasing temperature.Yu Shiratsuchia, Toshihiro Nakatani, Shin-ichi Kawahara, and Ryoichi Nakatani, Journal of Applied Physics 106, 033903 (2009); https://doi.org/10.1063/1.3182802

Positive Transfer Effect of Amygdaloid Kindling in Developing Rats

To study the hypothesis that seizure susceptibility in the young rat brain is higher than that in the adult brain, positive transfer effect (PTE) in amygdaloid kindling in rats was investigated at varing ages: 15 days, 18 days, 28 days, 40 days and 70 days. Although PTE was observed regardless of age, it was more pronounced in weaning rats than in adult rats

Persistence of Acquired Epileptogenesis in Amygdaloid-Kindled Rats: Relationship between the Initial Kindling Stages and Seizure Development in Rekindling

In order to gain insight into mechanisms underlying the persistence of the partial kindling effect, we suspended amygdaloid kindling at different seizure stages in rats, and investigated the effects on subsequent rekindling after a rest period of 2 months. Ten-week-old rats, implanted with bipolar electrodes, were separated by various initial kindling stages into 5 groups of rats, partially kindled to stages 1 (n = 7) and 2 (n = 10), fully kindled to stages 4 (n = 11) and 5 (n = 11), and control rats (n = 12) which were implanted but not stimulated initially. The number of stimulations required to elicit the first stage 5 seizure during rekindling was significantly lower in the fully kindled groups (P < 0.01 in the stage 4 group and P < 0.001 in the stage 5 group) than the control group. The cumulative afterdischarge duration during rekindling was significantly shorter in the fully kindled groups (P < 0.01 in both groups) than the control group. The latency of the first stage 5 seizure during rekindling was significantly shorter in the partially and fully kindled groups than the control group. These results suggest that epileptogenesis acquired at the partially kindled stage is different than that acquired at the fully kindled stage. However, the effects of the initial kindling on the latency to produce the stage 5 seizure during rekindling persisted both in the partially and fully kindled rats

Obliquity of an Earth-like planet from frequency modulation of its direct imaged lightcurve: mock analysis from general circulation model simulation

Direct-imaging techniques of exoplanets have made significant progress recently, and will eventually enable to monitor photometric and spectroscopic signals of earth-like habitable planets in the future. The presence of clouds, however, would remain as one of the most uncertain components in deciphering such direct-imaged signals of planets. We attempt to examine how the planetary obliquity produce different cloud patterns by performing a series of GCM (General Circulation Model) simulation runs using a set of parameters relevant for our Earth. Then we use the simulated photometric lightcurves to compute their frequency modulation due to the planetary spin-orbit coupling over an entire orbital period, and attempt to see to what extent one can estimate the obliquity of an Earth-twin. We find that it is possible to estimate the obliquity of an Earth-twin within the uncertainty of several degrees with a dedicated 4 m space telescope at 10 pc away from the system if the stellar flux is completely blocked. While our conclusion is based on several idealized assumptions, a frequency modulation of a directly-imaged earth-like planet offers a unique methodology to determine its obliquity.Comment: 29 pages, 18 figures, accepted for publication in Ap

Cytoplasmic control of Rab family small GTPases through BAG6

Rab family small GTPases are master regulators of distinct steps of intracellular vesicle trafficking in eukaryotic cells. GDP‐bound cytoplasmic forms of Rab proteins are prone to aggregation due to the exposure of hydrophobic groups but the machinery that determines the fate of Rab species in the cytosol has not been elucidated in detail. In this study, we find that BAG6 (BAT3/Scythe) predominantly recognizes a cryptic portion of GDP‐associated Rab8a, while its major GTP‐bound active form is not recognized. The hydrophobic residues of the Switch I region of Rab8a are essential for its interaction with BAG6 and the degradation of GDP‐Rab8a via the ubiquitin‐proteasome system. BAG6 prevents the excess accumulation of inactive Rab8a, whose accumulation impairs intracellular membrane trafficking. BAG6 binds not only Rab8a but also a functionally distinct set of Rab family proteins, and is also required for the correct distribution of Golgi and endosomal markers. From these observations, we suggest that Rab proteins represent a novel set of substrates for BAG6, and the BAG6‐mediated pathway is associated with the regulation of membrane vesicle trafficking events in mammalian cells

Cytology Reporting System for Lung Cancer from the Japan Lung Cancer Society and the Japanese Society of Clinical Cytology: An Extensive Study Containing More Benign Lesions

Introduction: The Japan Lung Cancer Society (JLCS) and the Japanese Society of Clinical Cytology (JSCC) have proposed a new four-tiered cytology reporting system for lung carcinoma (JLCS-JSCC system). Prior to the proposal, the Papanicolaou Society of Cytopathology (PSC) had proposed a revised reporting system (PSC system), which comprises the “neoplastic, benign neoplasm, and low-grade carcinoma” category (N-B-LG category), in addition to the 4 categories of the JLCS-JSCC system. This study aimed to evaluate the interobserver agreement of the JLCS-JSCC system with an additional dataset with more benign lesions in comparison with the PSC system. Methods: We analyzed 167 cytological samples, which included 17 benign lesions, obtained from the respiratory system. Seven observers classified these cases into each category by reviewing one Papanicolaou-stained slide per case according to the JLCS-JSCC system and PSC system. Results: The interobserver agreement was moderate in the JLCS-JSCC (k = 0.499) and PSC (k = 0.485) systems. Of the 167 samples, 17 samples were benign lesions: 7 pulmonary hamartomas, 5 sclerosing pneumocytomas, 2 squamous papillomas, one solitary fibrous tumor, one meningioma, and one lymphocytic proliferation. There were diverse sample types as follows: 11 touch smears, 3 brushing smears, 2 aspirations, and one sputum sample. Fourteen samples (82.3%) were categorized into “negative” or “atypical” by more than half of the observers in the JLCS-JSCC system. Conversely, 3 samples were categorized as “suspicious” or “malignant” by more than half of the observers in the JLCS-JSCC system. On the other hand, 11 samples (64.7%) were categorized into the N-B-LG category by more than half of the observers in the PSC system. Conclusions: The concordance rate in the JLCS-JSCC system was slightly higher than that in the PSC system; however, the interobserver agreement was moderate in both the JLCS-JSCC and PSC systems. These results indicate that both the JLCS-JSCC and PSC systems are clinically useful. Therefore, both systems are expected to have clinical applications. It may be important to integrate the 2 systems and construct a universal system that can be used more widely in clinical practice

Thymidine Catabolism as a Metabolic Strategy for Cancer Survival

Thymidine phosphorylase (TP), a rate-limiting enzyme in thymidine catabolism, plays a pivotal role in tumor progression; however, the mechanisms underlying this role are not fully understood. Here, we found that TP-mediated thymidine catabolism could supply the carbon source in the glycolytic pathway and thus contribute to cell survival under conditions of nutrient deprivation. In TP-expressing cells, thymidine was converted to metabolites, including glucose 6-phosphate, lactate, 5-phospho-α-D-ribose 1-diphosphate, and serine, via the glycolytic pathway both in vitro and in vivo. These thymidine-derived metabolites were required for the survival of cells under low-glucose conditions. Furthermore, activation of thymidine catabolism was observed in human gastric cancer. These findings demonstrate that thymidine can serve as a glycolytic pathway substrate in human cancer cells

Phase II study of ifosfamide, cisplatin, and vindesine combination in advanced non-small cell lung cancer.

Twenty-seven previously untreated patients with unresectable non-small cell lung cancer were treated with a 3-drug combination of ifosfamide, cisplatin, and vindesine as a phase II study. Patients received ifosfamide, 1.3g/m2, on days 1 to 5; cisplatin, 20mg/m2, on days 1 to 5; and vindesine, 3mg/m2, on days 1 and 8; with a sufficient parenteral hydration. Courses were repeated every 4 weeks. Twenty males and seven females with a median age of 61 years were treated and fully evaluated. Five patients had stage IIIA, seven had stage IIIB, and 15 had stage IV disease. One patient with adenocarcinoma achieved a complete response and 16 achieved a partial response, for an overall response rate of 63% (95% confidence limit: 45% to 81%). The median duration of response was 34 weeks (range: 9 to 52 weeks). The median survival time was 58 weeks for patients with IIIA/B disease, and 33 weeks for those with IV disease. The major toxicity was myelosuppression, however, it was generally well-tolerated. These results indicate that the 3-drug combination is active against non-small cell lung cancer and warrants further clinical trials.</p