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Nowadays, with the rapid expansion of social media as a means of quick communication, real-time disaster information is widely disseminated through these platforms. Determining which real-time and multi-modal disaster information can effectively support humanitarian aid has become a major challenge. In this paper, we propose novel end-to-end model, named GCN-based Semi-supervised Multi-modal Domain Adaptation (GSMDA), which consists of three essential modules: the GCN-based feature extraction module, the attention-based fusion module, and the MMD domain adaptation module. The GCN-based feature extraction module integrates text and image representations through GCNs, while the attention-based fusion module then merges these multi-modal representations using an attention mechanism. Finally, the MMD domain adaptation module is utilized to alleviate the dependence of GSMDA on source domain events by computing the maximum mean discrepancy across domains. our experiments results demonstrate that GSMDA outperforms the current state-of-the-art models in terms of performance and stability.

Human disorders associated with amyloid aggregation, such as Alzheimer's disease and Parkinson's disease, afflict the lives of millions worldwide. When peptides and proteins in the body are converted to amyloids, which have a tendency to aggregate, the toxic oligomers produced during the aggregation process can trigger a range of diseases. Nanoparticles (NPs) have been found to possess surface effects that can modulate the amyloid aggregation process and they have potential application value in the treatment of diseases related to amyloid aggregation and fibrillary tangles. In this review, we discuss recent progress relating to studies of nanoparticles that regulate amyloid aggregation. The review focuses on the factors influencing this regulation, which are important as guidelines for the future design of NPs for the treatment of amyloid aggregation. We describe the characterization methods that have been utilized so far in such studies. This review provides research information and characterization methods for the rational design of NPs, which should result in therapeutic strategies for amyloid diseases.

Fluorescence is widely used to detect functional groups and ions, and peptides are used in various fields due to their excellent biological activity. In recent years, research on fluorescent amino acids has intensified, especially with the natural fluorescent amino acids such as tryptophan (Trp), tyrosine (Tyr) and phenylalanine (Phe). They use their respective fluorophores to undergo π–π transition under excitation with light of a particular wavelength, and then release a large number of photons, which produce fluorescence. Thus, they are widely used as building units to enhance the fluorescence properties of other molecules. Peptide-based fluorescence technology has expanded the research in the field of biochemistry. Peptide-based fluorescence involving fluorescent amino acids not only retains the biocompatibility of peptides, but also relies on their fluorescent groups to enhance the fluorescent properties of the peptide itself, breaking the original limitations and connecting different fields to complement each other. This review summarizes the luminescence mechanism and fluorescent properties of the natural fluorescent amino acids and focuses on the fluorescence emission of peptides embedded with these fluorescent amino acids or fluorophores. Finally, we summarize the applications of peptide-based fluorescence in sensing drug release, metal ions and biomolecules, and present new challenges and expectations for the future development in this field.

The results from three laboratory model tests performed under various vacuum and surcharge loads with PVDs are reported. Different SLRs were adopted to investigate the effect on the consolidation of dredged soil. To measure the lateral displacement, a refitted inclinometer was developed and tested. In the tests, the settlement, lateral displacement, and vane shear strength were measured, and the degree of consolidation (DOC), horizontal coefficient of consolidation (Ch), and bearing capacity were calculated. The results indicate that larger SLR values promote consolidation. The largest vane shear strength, settlement, and Ch values were all obtained under the highest SLR, and the bearing capacity under this SLR was more than double that under the lowest SLR. The DOC was found to increase with the growth of the SLR. However, considering the vacuum pressure was higher in Case-III, the influence of SLR on reinforcement effect may not be so significant.

Guerbet amine-oxide was synthesized by using Guerbet acid, N,N′-diethyl-1,3-propanediamine and hydrogen peroxide. Its structure was confirmed by FT-IR spectra and mass spectra. The critical micelle concentration (CMC) and the interfacial tension between the crude oil and water were measured. The results showed that the CMC of the Guerbet amine-oxide is 2.14 × 10−5 mol/L and the interfacial tension could be lowered to ultralow levels. The core flood test showed that the surfactant and polymer binary system could increase oil recovery by 24.7% above the water flood.

In this paper, didodecylmethyl hydroxyl sulfobetaine was synthesized by reaction of didodecylmethyl amine with sodium 2-hydroxy-3-chloro propanesulfate. The interfacial tensions between Dagang crude oil and solution of the surfactants, solution of surfactant–polymer mixtures were measured. The effects of surfactant concentration and aging time on the interfacial tension were investigated. It is found that the synthesized betaine surfactant could reduce the interfacial tension to ultra-low without alkali, alcohol and the other additives in the absence of or presence of polymer. The surfactant–polymer system could lower the interfacial tension to ultra-low, even was aged for more than 2 weeks. The sand-pack flooding tests indicated that, with 0.2 wt% of the betaine and with 1,500 mg/L of polymer, 16.89 % of an additional OOIP (original oil in place) was recovered from a sand pack. This result suggested that the didodecylmethyl hydroxyl sulfobetaine might be a good surfactant candidate for enhanced oil recovery.

We study distributed algorithms for adapting transmit beamformers and linear receiver filters in a Time-Division Duplex Multiple-Input Multiple-Output (MIMO) interference network. Each transmitter transmits a single beam, and neither the transmitters nor receivers have a priori Channel State Information (CSI). Given a fixed set of powers, we present an adaptive version of the Max-SINR algorithm: pilot symbols are alternately transmitted in the forward direction (transmitters to receivers) and in the reverse direction (receivers to transmitters). Unlike previous channel estimation schemes, transmissions in each direction are synchronized across the source or destination nodes, and the pilots are used to update the filters/beams directly using a least squares criterion. To improve the performance with limited training, we include exponential weighting of the least squares objective across data frames. In addition, bi-directional training can be used to implement analog interference pricing for power control: training in the forward direction is used to measure received signal-to-interference plus noise ratios (SINRs) and interference prices, and those estimates combined with synchronous backward training are used to update the powers. Given sufficient training this method achieves the same performance as interference pricing updates with perfect CSI. Numerical results are presented that illustrate the performance of these methods in different settings.

Hexadecyl internal olefin sulfonate was synthesized using sulfur trioxide and internal olefin by sulfonation reaction. The internal olefin sulfonate was characterized by FT-IR and MS methods. Surfactant mixtures were formulated by internal olefin sulfonate and octadecyl hydroxysulfobetaine. It was found that the surfactant mixtures could lower the transient interfacial tension to ultra low values in the presence as well as the absence of polymer. Injection of 0.3 PV (pore volume) of the formulated slug followed by chase water, 15.15 % incremental recovery was obtained over water flood, accomplishing a final oil recovery of 64.78 % original-oil-in place.

This paper presents a comparative study of algorithms for jointly optimizing beamformers and receive filters in an interference network, where each node may have multiple antennas, each user transmits at most one data stream, and interference is treated as noise. We focus on techniques that seek good suboptimal solutions by means of iterative and distributed updates. Those include forward-backward iterative algorithms (max-signal-to-interference-plus-noise ratio (SINR) and interference leakage), weighted sum mean-squared error (MSE) algorithms, and interference pricing with incremental signal-to-noise ratio (SNR) adjustments. We compare their properties in terms of convergence and information exchange requirements, and then numerically evaluate their sum rate performance averaged over random (stationary) channel realizations. The numerical results show that the max-SINR algorithm achieves the maximum degrees of freedom (i.e., supports the maximum number of users with near-zero interference) and exhibits better convergence behavior at high SNRs than the weighted sum MSE algorithms. However, it assumes fixed power per user and achieves only a single point in the rate region whereas the weighted sum MSE criterion gives different points. In contrast, the incremental SNR algorithm adjusts the beam powers and deactivates users when interference alignment is infeasible. Furthermore, that algorithm can provide a slight increase in sum rate, relative to max-SINR, at the cost of additional iterations.

Hexadecylbenzene sulfonate was synthesized using aluminum trichloride catalyzed Friedel–Crafts reaction with hexadecyl linear internal olefin to benzene, sulfonated by chlorosulfonic acid, and neutralized with sodium hydroxide. The structure of the synthesized hexadecylbenzene sulfonate was characterized by infrared spectroscopy and mass spectroscopy. Surfactant mixtures were formulated by the synthesized hexadecylbenzene sulfonate and Kelamayi petroleum sulfonate. The results showed that the surfactant mixtures could reduce the interfacial tension to ultra-low values in the presence as well as the absence of polymer, at a very low concentration. The surfactant/polymer systems had a good thermal stability. The recovery factor was 59.85 % of original oil in place when the surfactant/polymer slug size was 0.3 pore volume of the core, compared with 45.59 % in case of water flood.

To investigate the transgenic expressing efficacy of helper-dependent adenoviral vector (HDAd) in vitro, we constructed a HDAd encoding enhanced green fluorescent protein (EGFP), denominated as HDAd/EGFP, performed large scale preparation and purification, and then identified the purified HDAd/EGFP under fluorescent microscope and electron microscope. After the concentration of HDAd/EGFP was determined by spectrophotometer, the transgenic expression efficiency of HDAd/EGFP was compared with first generation adenoviral vector encoding EGFP (FGAd/EGFP) in vitro. Therefore, we infected A549 cells with 2000 virus particles (vp) per cell by HDAd/EGFP and FGAd/EGFP respectively and analyzed EGFP expressing level by flow cytometry. Consequently, the fluorescent expression rate and fluorescent intensity of EGFP were higher in early infected A549 cells by HDAd/EGFP than by FGAd/EGFP. HDAd, capable of expressing transgene instantly and efficiently in vitro, is a potential vaccine vector.

We study distributed algorithms for adjusting beamforming vectors and receiver filters in multiple-input multiple-output (MIMO) interference networks, with the assumption that each user uses a single beam and a linear filter at the receiver. In such a setting there have been several distributed algorithms studied for maximizing the sum-rate or sum-utility assuming perfect channel state information (CSI) at the transmitters and receivers. The focus of this paper is to study adaptive algorithms for time-varying channels, without assuming any CSI at the transmitters or receivers. Specifically, we consider an adaptive version of the recent Max-SINR algorithm for a time-division duplex system. This algorithm uses a period of bi-directional training followed by a block of data transmission. Training in the forward direction is sent using the current beam-formers and used to adapt the receive filters. Training in the reverse direction is sent using the current receive filters as beams and used to adapt the transmit beamformers. The adaptation of both receive filters and beamformers is done using a least-squares objective for the current block. In order to improve the performance when the training data is limited, we also consider using exponentially weighted data from previous blocks. Numerical results are presented that compare the performance of the algorithms in different settings., Comment: 7 pages, 5 figures. An earlier version appeared in 44th Annual Conference on Information Sciences and Systems (CISS), Princeton, NJ, March 2010

We study distributed algorithms for updating transmit precoding matrices for a two-user Multi-Input/Multi-Output (MIMO) interference channel. Our objective is to maximize the sum rate with linear Minimum Mean Squared Error (MMSE) receivers, treating the interference as additive Gaussian noise. An iterative approach is considered in which given a set of precoding matrices and powers, each receiver announces an interference price (marginal decrease in rate due to an increase in interference) for each received beam, corresponding to a column of the precoding matrix. Given the interference prices from the neighboring receiver, and also knowledge of the appropriate cross-channel matrices, the transmitter can then update the beams and powers to maximize the rate minus the interference cost. Variations on this approach are presented in which beams are added sequentially (and then fixed), and in which all beams and associated powers are adjusted at each iteration. Numerical results are presented, which compare these algorithms with iterative water-filling (which requires no information exchange), and a centralized optimization algorithm, which finds locally optimal solutions. Our results show that the distributed algorithms perform close to the centralized algorithm, and by adapting the rank of the precoder matrices, achieve the optimal high-SNR slope.

Helper-dependent adenoviral vector (HDAd) lacking all viral coding sequences with the advantages of minimal immunogenicity, negligible chronic-toxicity, and durable transgene expression over first-generation adenoviral vector (FGAd). HDAd vehicles have demonstrated tremendous potential for gene therapy in animal models for inherited diseases, neurodegenerative diseases and cancer etc. Additionally, the large cloning capacity of HdAd, up to 37 kb, permits the delivery of whole genemic loci, multiple transgenes. In this review we characterize the basic features of HdAd and summarize some of their experimental and potential clinical applications both at present and in future.

To achieve the full multiplexing gain of MIMO interference networks at high SNRs, the interference from different transmitters must be aligned in lower-dimensional subspaces at the receivers. Recently a distributed “max-SINR” algorithm for precoder optimization has been proposed that achieves interference alignment for sufficiently high SNRs. We show that this algorithm can be interpreted as a variation of an algorithm that minimizes the sum Mean Squared Error (MSE). To maximize sum utility, where the utility depends on rate or SINR, a weighted sum MSE objective is used to compute the beams, where the weights are updated according to the sum utility objective. We specify a class of utility functions for which convergence of the sum utility to a local optimum is guaranteed with asynchronous updates of beams, receiver filters, and utility weights. Numerical results are presented, which show that this method achieves interference alignment at high SNRs, and can achieve different points on the boundary of the achievable rate region by adjusting the MSE weights.

We study a distributed algorithm for adapting transmit beamforming vectors in a multi-antenna peer-to-peer wireless network. The algorithm attempts to maximize a sum of per-user utility functions, where each user's utility is a function of his transmission rate, or equivalently the received signal-to-interference plus noise ratio (SINR). This is accomplished by exchanging interference prices, each of which represents the marginal cost of interference to a particular user. Given the interference prices, users update their beamforming vectors to maximize their utility minus the cost of interference. For a two-user system, we show that this algorithm converges for a suitable class of utility functions. Convergence of the algorithm with more than two users is illustrated numerically.

Diacyl amino acid surfactant was prepared using lauroyl chloride and l-lysine. The structure of the synthesized surfactant was confirmed by infrared spectroscopy and mass spectroscopy. The ultralow interfacial tension could be achieved when the diacyl amino acid surfactant is mixed with sulfonate in the presence of polymer as well as absence of polymer. Core flood experiments showed that 17.8 % additional oil could be recovered by injection of 0.3 pore volume of surfactant–polymer solution, making the total oil recovery reach 66.1 %.

Surfactant is a kind of chemical that is widely used in the oilfield. It often serves as chemical oil displacement agents in the surfactant–polymer flooding or alkali–surfactant–polymer flooding. The commonly used surfactant is petroleum sulfonate. However, its unstable property often limits its use. In this paper, erucamidopropyl dimethyl amine oxide was prepared and its potential use in surfactant–polymer flooding was investigated. The results showed that the interfacial tension between crude oil and surfactant–polymer solution could be lowered to ultralow at a concentration of 0.05% (m/m) surfactant. The surfactant–polymer system (0.05% of surfactant and 1500 mg/L of polymer) could withstand adsorption twice. The core flood test indicated the above system could give 22.5% of incremental oil recovery over water flood.