53 research outputs found
Structured Memetic Automation for Online Human-like Social Behavior Learning
Meme automaton is an adaptive entity that autonomously acquires an increasing level of capability and intelligence through embedded memes evolving independently or via social interactions. This paper begins a study on memetic multiagent system (MeMAS) toward human-like social agents with memetic automaton. We introduce a potentially rich meme-inspired design and operational model, with Darwin's theory of natural selection and Dawkins' notion of a meme as the principal driving forces behind interactions among agents, whereby memes form the fundamental building blocks of the agents' mind universe. To improve the efficiency and scalability of MeMAS, we propose memetic agents with structured memes in this paper. Particularly, we focus on meme selection design where the commonly used elitist strategy is further improved by assimilating the notion of like-attracts-like in the human learning. We conduct experimental study on multiple problem domains and show the performance of the proposed MeMAS on human-like social behavior
Influence Maximization with Novelty Decay in Social Networks
Influence maximization problem is to find a set of seed nodes in a social network such that their influence spread is maximized under certain propagation models. A few algorithms have been proposed for solving this problem. However, they have not considered the impact of novelty decay on influence propagation, i.e., repeated exposures will have diminishing influence on users. In this paper, we consider the problem of influence maximization with novelty decay (IMND). We investigate the effect of novelty decay on influence propagation on real-life datasets and formulate the IMND problem. We further analyze the problem properties and propose an influence estimation technique. We demonstrate the performance of our algorithms on four social networks
Hemp seeds attenuate loperamide-induced constipation in mice
Constipation is a common gastrointestinal disease that seriously affects human physical and mental health. Studies have reported that hemp seeds can improve constipation, however the specific mechanism is still unclear. This study investigates that hemp seed (HS) and its water-ethanol extract (HSE) attenuates loperamide-induced constipation in mice. The research results show that: the fecal water content and small intestinal transit rate of mice in the hemp seed group and hemp seed hydroalcoholic extract group were significantly increased compared with MC group, and the first red feces defecation time was significantly shortened; HS and HSE significantly influence serum levels of Gastrin (Gas), motilin (MTL), substance P (SP), and endothelin (ET), potentially mediating their effects on gastrointestinal motility. HS and HSE can improve colon inflammation in constipated mice with H&E staining. Compared with the model of constipation group, the content of short-chain fatty acids in the HS group and HSE group increased significantly. Gut microbiome studies have shown that the structure and abundance of intestinal flora are altered. HS and HSE changed the abundance of Odoribacter, Bacteroide, Lactobacillus and Prevotella. Together, these results suggest that HS have the potential to stimulate the proliferation of beneficial gut microbes and promote intestinal motility, thereby improving gut health and relieving symptoms of constipation
Improved Performance of Recombinant Protein A Immobilized on Agarose Beads by Site-Specific Conjugation
Protein
A affinity adsorbent with high antibody-binding capacity
plays a prominent part in the purification of biopharmaceuticals to
decrease the manufacturing costs. We describe a site-specific covalent
conjugation strategy for protein A to immobilize on agarose beads.
Recombinant protein A, which has one cysteine introduced at the C
terminus through genetic engineering technology, was immobilized site-specifically
on maleimide-functionalized agarose beads by the thiol–maleimide
reaction. As a comparison, the recombinant protein A was randomly
immobilized on the aldehyde-functionalized agarose beads via free
amino groups on the protein surface. The site-specific conjugation
of recombinant protein A on the agarose beads was validated through
the assay of free SH groups on the adsorbents using the Ellman’s
reagent. Adsorbents containing various amounts of protein A were used
to adsorb antibody from human plasma. Analysis of immunoturbidimetry
showed that the adsorbed fractions contained the 90.1% IgG, 4.2% IgA,
and 5.7% IgM. The maximal antibodies-binding capacities with static
adsorption and dynamic adsorption were approximately 64 and 50 mg,
respectively, per swollen gram for site-specifically conjugated adsorbent
and 31 and 26 mg for randomly conjugated adsorbent. Remarkably, the
high antibody-binding capacity for site-specifically conjugated adsorbent
outperformed the existing commercial protein A Sepharose (approximately
30 mg/g). The orientation of a protein is crucial for its activity
after immobilization, and these results demonstrate that the site-specifically
conjugated protein molecule is in a functionally active form to interact
with the antibody with weak steric hindrance. The proposed approach
may be an attractive strategy to synthesize affinity adsorbents with
high-binding capacity
APOA1 mRNA and protein in kidney renal clear cell carcinoma correlate with the disease outcome
Abstract Renal cancer is one of the most common malignant tumors with high mortality, and kidney renal clear cell carcinoma (KIRC) is the most common type of renal cancer. We attempted to evaluate the clinical and prognostic significance of Apolipoprotein A1 (APOA1) mRNA and protein in KIRC patients. Clinical data along with RNA-sequencing data were downloaded from UCSC Xena. The Human Protein Atlas database was searched to reveal APOA1 protein expression profiles in KIRC and normal renal tissues. The TIMER database was applied to determine the correlations of APOA1 with immune cells and PD-1 and PD-L1 in KIRC. Ninety-one cases of KIRC patients and 93 healthy controls from our hospital were enrolled for clinical validation. Levels of APOA1 mRNA in KIRC tissues (N = 535) are not only lower than the levels in normal renal tissues (N = 117), but also in paired normal renal tissues (N = 72). High expression of APOA1 mRNA at the time of surgery was correlated with worse overall survival (OS) (HR 1.66; p = 0.037) and disease-free survival (DFS) (HR 1.65; p = 0.047), and APOA1 DNA methylation was linked to worse OS (HR 2.1; p = 0.001) rather than DFS (HR 1.12; p = 0.624) in KIRC patients. Concentrations of preoperative serum APOA1 protein were markedly decreased in KIRC patients compared to healthy controls (p < 0.01), and low levels of APOA1 protein predicted less favorable OS than those with high levels (HR = 2.84, p = 0.0407). APOA1 negatively correlated with various immune cell infiltrates and PD-L1 expression (r = − 0.283, p = 2.74e−11) according to the TIMER database. Low levels of APOA1 mRNA at the time of surgery predict favorable survival in KIRC patients. Our results provide insights to identify a novel prognostic index with great clinical utility
Postoperative epidural hematoma as a rare complication after intracranial tumor resection: a case series report and causes analysis
Abstract Background To review the treatment and the causes of postoperative epidural hematoma (PEDH) after intracranial tumor resection. Method A retrospective case study was conducted to examine a series of patients who developed PEDH as a complication following intracranial tumor resection between January 2016 and June 2021. The study collected data from hospital charts, including clinical status at admission, imaging results, histopathologic findings, surgical management, complications, and outcomes. Causes of PEDH were evaluated through a review of operative notes and discussions with the surgical team. Results Twenty-five patients (10 males, 15 females; median age 42 years, range 11–61 years; median medical history 27 months, range 1–96 months) were enrolled in the study. Regarding tumor location, 16 cases exhibited supratentorial brain tumors, 4 cases had infratentorial brain tumors, 2 cases of tumors occurred in the petroclival region, 2 cases in the peritorcular region, and 1 case in the pineal region. Four of these cases were complicated with supratentorial hydrocephalus. The 25 cases in this study were classified into four types based on location. Type 1 refers to EDHs that occur at the adjacent site of the operative field without involvement of the surgical area. Type 2 includes hematomas that occur at the adjacent site of the surgical area and the surgical area. Type 3 includes EDHs that occur in distant areas, and type 4 involves EDHs in the surgical field. The numbers of cases of types 1, 2, 3, and 4 PEDHs were 16, 2, 3, and 4 cases, respectively. Most PEDHs were associated with reduced ICP after craniotomy due to intracranial tumor resection and substantial loss of CSF. All patients achieved satisfactory outcomes after hematoma evacuation. Conclusion The decrease in ICP resulting from intracranial tumor resection and CSF loss might lead to PEDHs. By employing optimized surgical techniques and meticulous patient management to prevent rapid decreases in ICP and dural detachment, we can potentially lower the incidence of PEDHs. Additionally, prompt evacuation of hematomas can contribute to positive outcomes
Homo- and Hetero-Recyclable Polyesters with High Refractive Index from CO2, 1,3-Butadiene and Thiols
α-Ethylidene-δ-vinyl-δ-valerolactone (EVL) is the only intermediate to synthesize copolymers of CO2 with 1,3-butadiene whose ring-opening polymerization (ROP), however, is obstructed by the tiglate group. The saturation of the conjugated double bond is essential to the living ROP of EVL, while previous reports involve irreversible hydrogenation. In the contribution, EVL derivatives are synthesized through Michael addition reaction to saturate the conjugated double bond as well as introduce various groups to synthesize polyesters with tunable glass-transition temperatures (Tg) from -45 °C to 3 °C and excellent refractive index between 1.64 and 1.85. Living and controlled polymerizations lead to polyesters with designable number average molecular weights (Mn = 6.9-12.8 kg∙mol-1) and narrow dispersities (Đ = 1.08-1.19). The obtained polyesters are able to be recycled to the corresponding monomers which can prepare comparable polymers with identical side groups, realizing the homo-recycling. The monomers are capable of being recycled to EVL and thiols through retro-Michael addition reaction, and then the recycled EVL can be re-functionalized to generate a new monomer which produces a polyester with another side group, fulfilling the hetero-recycling. We propose an “addition-elimination-re-addition” strategy for EVL derivatives and the corresponding polyesters
Design and Theoretical Investigation of an on Chip Two-Dimensional Newton’s Ring-like Plasmonic Sensor for Differentiating the Chirality of Circularly Polarized Lights
In this paper, an on chip two-dimensional Newton’s ring-like plasmonic sensor is designed for differentiating the chirality of circularly polarized lights (CPLS). The structure of the plasmonic sensor consists of a circular arc slit and an array of periodic rectangular nano-grooves that are etched into a silver film. When the sensor is illuminated by CPLS with a given chirality, the surface plasmon polariton waves generated by the slit and nano-groove array will selectively interfere with each other in the near field, which results in two different transmitted light intensity distributions in the far field. The generated far-field light intensity distributions are utilized as criteria to qualitatively differentiate the concrete chirality of the incident CPLS. The finite difference time domain method is utilized to theoretically investigate the function of the designed plasmonic sensor. The simulated results indicated that the proposed sensor has the ability to visually display the chirality information in the far field, and can provide a tool to conveniently and qualitatively differentiate the chirality of CPLS in the far field
- …