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The delooping level conjecture holds for all Artin algebras if and only if, for all Artin algebras, the delooping level of an algebra being finite implies that the delooping level of its opposite algebra is also finite.

We provide a technique to glue simple-minded collections along a recollement of Hom-finite Krull-Schmidt triangulated categories over a field. This gluing technique for simple-minded collections is shown to be compatible with those for gluing bounded $t$-structures, silting objects, and co-$t$-structures in the literature. Furthermore, it also enjoys the properties of preserving partial order and commuting with the operation of mutation., Comment: 23 pages

Indoor location-based service is getting more and more attention. However, most of indoor localization methods paid attention to the horizontal localization in one floor and little concerned the floor estimation in one building vertically. Generally, base stations around a building can be seen as being in a horizontal plane. Due to near or far to these base stations, position changes in the same floor will introduce different reference signal receiving power(RSRP) change separately. But position changes in the vertical direction will make RSRP change together, which makes RSRP difference not obvious to achieve good floor estimation. Therefore, in this paper we propose a novel floor estimation method in the cellular networks within one building. In offline phase, based on principal component analysis (PCA) and Adaboost, the collected cellular signals are used to train a floor estimation model, where we propose a floor division strategy to improve the floor estimation accuracy. In online phase, the cellular signals are utilized by the floor estimation model to get the floor estimation results. The experiment results show that the floor estimation accuracy of the proposed method outperforms others.

The immense diffusion of smart mobile devices increase the usage of WiFi as a state-of-the-art wireless communication standard dramatically, and it also renders fingerprinting method for high-accuracy indoor localization possible. However, the fundamental challenge of existing fingerprinting localization is that the complicated indoor spatial structure brings great difficulty to exploit the relationship between received signal strength (RSS) distribution and the process of fingerprint matching. To address this problem, in this paper, we focus on integrating the signal pathloss model into distance metric learning, and a novel cost similar to the Large Margin Nearest Neighbor (LMNN) is designed to conduct offline metric learning procedure. The proposed metric learning, which is pathloss model practically considered to learn the mapping between signal strength distribution and physical space structure, aims to obtain a reasonable distance matrix for k Nearest Neighbor (KNN) based indoor localization. Experiment results corroborate that the proposed metric learning method can further improve the indoor localization accuracy compared with the conventional methods and its effectiveness is validated extensively in various cases for testing.

In recent years, Location-Based Services (LBS) have been widely applied in people's life with various localization technologies. Because outdoor localization methods are not suitable for indoor environments, various indoor localization methods have been developed. Among the existing indoor localization methods, Wi-Fi fingerprinting localization has attracted great concerns because of its wide applicability, simple deployment, and comparable performance. This paper proposed an interpolation method for radio map establishment based on RSS clustering and propagation model optimization. Fuzzy C-Means (FCM) clustering algorithm is used to cluster the Received Signal Strength (RSS) samples collected at Reference Points (RPs). In each cluster, propagation model parameters are optimized. Then RSS samples are estimated at select locations for radio map establishment. With the radio map after interpolation, more accurate localization results can be computed using K Nearest Neighbors (KNN) fingerprinting algorithm.

Regulatory T cells (Tregs) expressing FOXP3 are essential for the maintenance of self-tolerance and are deficient in many common autoimmune diseases. Immune tolerance is maintained in part by IL-2 and deficiencies in the IL-2 pathway cause reduced Treg function and an increased risk of autoimmunity. Recent studies expanding Tregs in vivo with low-dose IL-2 achieved major clinical successes highlighting the potential to optimize this pleiotropic cytokine for inflammatory and autoimmune disease indications. Here we compare the clinically approved IL-2 molecule, Proleukin, with two engineered IL-2 molecules with long half-lives owing to their fusion in monovalent and bivalent stoichiometry to a non-FcRγ binding human IgG1. Using nonhuman primates, we demonstrate that single ultra-low doses of IL-2 fusion proteins induce a prolonged state of in vivo activation that increases Tregs for an extended period of time similar to multiple-dose Proleukin. One of the common pleiotropic effects of high dose IL-2 treatment, eosinophilia, is eliminated at doses of the IL-2 fusion proteins that greatly expand Tregs. The long half-lives of the IL-2 fusion proteins facilitated a detailed characterization of an IL-2 dose response driving Treg expansion that correlates with increasingly sustained, suprathreshold pSTAT5a induction and subsequent sustained increases in the expression of CD25, FOXP3 and Ki-67 with retention of Treg-specific epigenetic signatures at FOXP3 and CTLA4.

Background Tumor invasion or adherence to the portal vein–superior mesenteric vein (PV/SMV) may be encountered during pancreatic surgery. In such cases, venous resection and reconstruction might be required for complete resection of the tumor. We report an innovative technique in which the graft for PV/SMV reconstruction was made with the falciform ligament. Methods Between May 2011 and July 2016, PV/SMV reconstruction with a falciform ligament graft was performed in 10 cases during pancreatectomy. Among these cases, including six cases with a patch graft and four cases with a conduit graft. Retrospective reviews of medical records and radiologic studies were performed. Results Ten patients with pancreatobiliary cancer underwent en bloc tumor resection with concurrent PV/SMV resection and reconstruction with a falciform ligament graft. There were six males and four females, and the mean age was 65.3 ± 9.4 (48-80) y. Using Doppler ultrasound examination, all 10 grafts were shown to be patent at postoperative 2 wk. However, occlusion was found in one case with conduit graft and stenosis in the other three cases with conduit graft using enhanced computed tomography at postoperative 2 mo. Complete patency was shown in three of six cases with patch graft and stenosis in the other three cases at 2 mo after the operation. Although occlusion or stenosis of the grafts was observed, no severe adverse events occurred, and normal liver function was discovered in all 10 cases at postoperative 2 mo. Conclusions Falciform ligament grafts might be considered for reconstruction of PV/SMV in the absence of appropriate vascular grafts.

The concentrated leach ate of the Chengdu Leach ate Treatment Plant was collected as a subject of case study. It was a very dark coloured liquid possessing high COD, very low BOD5 and low ammonia nitrogen concentration. The combination of coagulation and fly ash absorption was used to treat the concentrated leach ate in this study. The effects of pH, coagulant dosage and settling time on COD removal in coagulation process were investigated by single-factor and orthogonal experiments. Results showed that the optimum value was approximately pH 5, aluminium sulfate dosage 1.5g and settling time 50min. The influence of operating factors followed the order: coagulant dosage£¾pH£¾ settling time. Fly ash absorption experiments were performed after finishing the surface modification of fly ash in acid condition. The effects of pH, fly ash dosage and stirring time on COD removal were also studied by single factor. Results showed that the optimum value was about pH5, fly ash dosage 2.5g and stirring time 2.5h. After finishing the final step of fly ash absorption, the overall remova1 rate of COD was above 80%.