Energy Efficient Ant Colony Algorithms for Data Aggregation in Wireless Sensor Networks

In this paper, a family of ant colony algorithms called DAACA for data aggregation has been presented which contains three phases: the initialization, packet transmission and operations on pheromones. After initialization, each node estimates the remaining energy and the amount of pheromones to compute the probabilities used for dynamically selecting the next hop. After certain rounds of transmissions, the pheromones adjustment is performed periodically, which combines the advantages of both global and local pheromones adjustment for evaporating or depositing pheromones. Four different pheromones adjustment strategies are designed to achieve the global optimal network lifetime, namely Basic-DAACA, ES-DAACA, MM-DAACA and ACS-DAACA. Compared with some other data aggregation algorithms, DAACA shows higher superiority on average degree of nodes, energy efficiency, prolonging the network lifetime, computation complexity and success ratio of one hop transmission. At last we analyze the characteristic of DAACA in the aspects of robustness, fault tolerance and scalability.Comment: To appear in Journal of Computer and System Science

Microphase separation, stress relaxation and creep behavior of polyurethane nanocomposites

The microphase separation of polyurethane (PU) nanocomposite was studied. The result suggests that the addition of clay leads to a decrease in the size of hard domain and an increase in the degree of microphase separation. The stress relaxation and creep behavior of blank PU and PU/clay nanocomposites were investigated. The relaxation time spectrum and retardant time spectrum were derived according to the generalized Maxwell model and Voigt model with a Tikhonov regularization method. The characteristic relaxation time was identified with the corresponding relaxation process. At a small strain, the relaxation was mainly attributed to uncoiling/disentangling of soft segment chain network in the soft phase, with a single characteristic relaxation time in the range of 5~100s. The increase in the hard segment content leads to a decrease in the relaxation time, and the addition of clay leads to an increase in the relaxation time. At large strains, the multi-peak relaxations occurred, and they were attributed to the breakup of interconnected hard domains and pull-out of soft segment chains from hard domains, together with the disentangling of soft segment chain network in the soft phase. The creep results are in consistent with that of the stress relaxation. The relaxation and creep behavior were related to microphase separation of polyurethane. This study suggested that the relaxation spectrum H(ï´) can be used to examine the complicated relaxation processes for a multi-phase and multi-component polymer system

Fully Automated Deep Learning-enabled Detection for Hepatic Steatosis on Computed Tomography: A Multicenter International Validation Study

Despite high global prevalence of hepatic steatosis, no automated diagnostics demonstrated generalizability in detecting steatosis on multiple international datasets. Traditionally, hepatic steatosis detection relies on clinicians selecting the region of interest (ROI) on computed tomography (CT) to measure liver attenuation. ROI selection demands time and expertise, and therefore is not routinely performed in populations. To automate the process, we validated an existing artificial intelligence (AI) system for 3D liver segmentation and used it to purpose a novel method: AI-ROI, which could automatically select the ROI for attenuation measurements. AI segmentation and AI-ROI method were evaluated on 1,014 non-contrast enhanced chest CT images from eight international datasets: LIDC-IDRI, NSCLC-Lung1, RIDER, VESSEL12, RICORD-1A, RICORD-1B, COVID-19-Italy, and COVID-19-China. AI segmentation achieved a mean dice coefficient of 0.957. Attenuations measured by AI-ROI showed no significant differences (p = 0.545) and a reduction of 71% time compared to expert measurements. The area under the curve (AUC) of the steatosis classification of AI-ROI is 0.921 (95% CI: 0.883 - 0.959). If performed as a routine screening method, our AI protocol could potentially allow early non-invasive, non-pharmacological preventative interventions for hepatic steatosis. 1,014 expert-annotated liver segmentations of patients with hepatic steatosis annotations can be downloaded here: https://drive.google.com/drive/folders/1-g_zJeAaZXYXGqL1OeF6pUjr6KB0igJX

Real-time stability of a hepatitis E vaccine (Hecolin®) demonstrated with potency assays and multifaceted physicochemical methods

The first prophylactic vaccine against hepatitis E virus (HEV), Hecolin®, was licensed in China. Recombinant p239 virus-like particle (VLP) is its active component with dimeric protein as the basic building block harboring the immuno dominant and neutralizing epitopes. The real time and real condition stability of the prefilled syringes for the vaccine was demonstrated using both in vivo mouse potency and in vitro antigenicity assays. A total of 12 lots of Hecolin® were assessed with a set of assays after storage at 2-8 °C for 24 months. The particle characteristics of p239 VLP recovered from the aluminum-containing adjuvant was assessed with different methods including analytical ultracentrifugation, high performance size exclusion chromatography and transmission electron microscopy. The thermal and conformational stability of the adsorbed antigen was assessed using differential scanning calorimetry. The protein integrity of the recovered p239 antigen was demonstrated using SDS-PAGE with silvering staining, LC-MS and MALDI-TOF MS. Most importantly, the binding activity to the neutralizing antibody or vaccine antigenicity was measured using an epitope-specific and real-time SPR assay and a monoclonal antibody-based sandwich ELISA. Taken together, the overall good stability of the Hecolin® prefilled syringes was demonstrated with unaltered molecular and functional attributes after storage at 2-8 °C for 24 months

Excitation of semiconductor nanowires using individually addressable micro-LED arrays

Optical pumping of nanowire emitters, embedded in polymeric waveguides is achieved using a micro-LED array at 410 nm. The micro-LED-on-CMOS chip allows for individual pixel control and therefore parallel pumping of multiple emitters simultaneously. The nanowires are integrated on-chip using high-accuracy transfer-printing and laser lithography

Scalable optical excitation and modulation of semiconductor nanowire emitters

We show that individually addressable micro-LED-on-CMOS arrays can be used as scalable optical excitation sources for arrayed semiconductor nanowire devices. This approach is used to demonstrate optical modulation at MHz rates of heterogeneously integrated nanowire-emitters

Requirement of the phosphatidylinositol 3-kinase/Akt signaling pathway for the effect of nicotine on interleukin-1beta-induced chondrocyte apoptosis in a rat model of osteoarthritis

National Natural Science Foundation of China [81072015]; Natural Science Foundation of Fujian, China [2010D007]; Medical Innovation Foundation of Fujian, China [2011-CXB-36]; Xiamen Science and Technology Key program grant, Fujian, ChinaChondrocyte apoptosis is mainly responsible for the progressive degeneration of cartilage in osteoarthritis (OA). Interleukin-1beta (IL-1 beta) was widely used as a modulating and chondrocyte apoptosis-inducing agent. Nicotine is able to confer resistance to apoptosis and promote cell survival in some cell lines, but its regulatory mechanism is ambiguous. We aimed to investigate the effect of nicotine on IL-1 beta-induced chondrocyte apoptosis and the mechanism underlying how nicotine antagonizes IL-1 beta-induced apoptosis of rat chondrocytes. Chondrocytes isolated from newborn rat joints were exposed to IL-1 beta. The cell viability was analyzed by the MTT (3-(4,5-dimethylthiazol-2yl)-2,5-diphenyl tetrazolium bromide) assay, and the apoptotic cells were counted with DAPI staining. The levels of Akt, phosphorylated-Akt (p-Akt) and downstream protein targets of Akt were detected by western blotting. The results showed that nicotine neutralized the effect of IL-1 beta on chondrocytes by activating PI3K/Akt signaling pathways, including the PI3K/Akt/Bcl-2 pathway, to block IL-1 beta-induced cell apoptosis and the PI3K/Akt/p70S6K (p70S6 kinase)/S6 pathway for promoting protein synthesis, modulating its downstream effectors such as TIMP-1 and MMP-13. Activation of the PI3K/Akt pathway is, in part, required for the effect of nicotine on IL-1 beta-induced chondrocyte apoptosis in a rat model of osteoarthritis. (C) 2012 Elsevier Inc. All rights reserved

Clinicopathological characteristics of gastric cancer patients with dermatomyositis and analysis of perioperative management: a case series study

BackgroundThis study aimed to investigate the clinical characteristics of gastric cancer (GC) patients with dermatomyositis (DM) and summarize the perioperative outcomes.MethodsThe clinical and pathological data of five patients diagnosed with co-occurring DM and GC (DM-GC group) were retrospectively analyzed, who were admitted to the Department of Gastrointestinal Surgery at Ren ji Hospital, Shanghai Jiao Tong University, between January 2012 and April 2023. Their data were compared with 618 GC patients (GC-1 group) from September 2016 to August 2017 and 35 GC patients who were meticulously screened from 14,580 GC cases from January 2012 and April 2023. The matching criteria included identical gender, age, tumor location, TNM stage, and surgical procedure (7 GC patients were matched for each DM-GC patient).ResultsAnalysis indicated that the DM-GC group comprised four female and one male patient. The female proportion was significantly higher (P = 0.032) than that of GC-1 group. In DM-GC group, four DM patients were diagnosed as GC within 12 months. One DM patients was diagnosed as GC within 15 months. Among them, four patients presented with varying degrees of skin rashes, muscle weakness while one patient had elevated CK levels as the typical symptom. Similarly, the preoperative tumor markers (CA-199 and CA-125) in the DM-GC group were significantly higher than normal levels (CA-199: 100 vs. 28.6%, P = 0.002; CA-125: 40 vs. 2.9%, P = 0.003) compared to GC-2 group. Moreover, postoperative complication incidence and the length of hospital stay were significantly higher in the DM-GC than GC-2 group [complication rate: 40 vs. 8.6%, P = 0.047; hospital stay: 15 days (range: 9–28) vs. 9 days (range: 8–10), P = 0.021].ConclusionGC Patients with dermatomyositis are more prone to experience postoperative complications and longer hospital stay

Evolution favors protein mutational robustness in sufficiently large populations

BACKGROUND: An important question is whether evolution favors properties such as mutational robustness or evolvability that do not directly benefit any individual, but can influence the course of future evolution. Functionally similar proteins can differ substantially in their robustness to mutations and capacity to evolve new functions, but it has remained unclear whether any of these differences might be due to evolutionary selection for these properties. RESULTS: Here we use laboratory experiments to demonstrate that evolution favors protein mutational robustness if the evolving population is sufficiently large. We neutrally evolve cytochrome P450 proteins under identical selection pressures and mutation rates in populations of different sizes, and show that proteins from the larger and thus more polymorphic population tend towards higher mutational robustness. Proteins from the larger population also evolve greater stability, a biophysical property that is known to enhance both mutational robustness and evolvability. The excess mutational robustness and stability is well described by existing mathematical theories, and can be quantitatively related to the way that the proteins occupy their neutral network. CONCLUSIONS: Our work is the first experimental demonstration of the general tendency of evolution to favor mutational robustness and protein stability in highly polymorphic populations. We suggest that this phenomenon may contribute to the mutational robustness and evolvability of viruses and bacteria that exist in large populations

Advanced transfer printing with in-situ optical monitoring for the integration of micron-scale devices

Transfer printing integration of planar membrane devices on photonic and electronic circuits is becoming a well established technology. Typical systems incorporate a single planar layer printed into full contact with the host substrate. In this work we present an advanced transfer print system that enables printing of optical devices in non-planar geometries and allows in-situ optical monitoring of devices. We show micro-resonators with air-clad whispering gallery modes coupled to on-chip waveguides, inverted device printing and three dimensionally assembled micro-cavities incorporating semiconductor micro-lenses and nanowire lasers. We demonstrate printing onto non-standard substrates including optical chip facets and single-mode fibre ends. The optical fibre printing was carried out with alignment assistance from in-situ optical coupling through the transfer printing system in real-time allowing active alignment of the system