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The low reliability of feature and tracking box detection remains a problem in visual object tracking. Currently, most discriminative correlation filter (DCF) trackers integrate multiple types of features with fixed weights. However, these approaches cannot be adapted to complex scenes when fixed weights are used for features. In addition, the tracking box of traditional DCF trackers lacks scale and aspect ratio adaptability, which can inevitably lead to excessive background noise. To address these problems, we propose a robust tracking method for unmanned aerial vehicles (UAVs) using dynamic feature weight selection. Specifically, we define a feature weight pool that contains multiple weights for different features. In each frame, we select a weight combination with high reliability from the weight pool. This approach is a form of dynamic feature weight selection since the feature weight may be different for each frame. Furthermore, EdgeBoxes is combined with the DSST and can adapt well to the scale and aspect ratio of the tracking box. Extensive experiments based on UAV123@10fps, VisDrone2018-test-dev, and UAVDT show that our tracker is superior to other state-of-the-art trackers. It is noteworthy that the proposed dynamic feature weight selection method can be embedded into any tracking model using multiple features. [ABSTRACT FROM AUTHOR]

Obstructive Sleep Apnea (OSA) is related to repeated upper airway collapse, intermittent hypoxia, and intestinal barrier dysfunction. The resulting damage to the intestinal barrier may affect or be affected by the intestinal microbiota. A prospective case–control was used, including 48 subjects from Sleep Medicine Center of Nanfang Hospital. Sleep apnea was diagnosed by overnight polysomnography. Fecal samples and blood samples were collected from subjects to detect fecal microbiome composition (by 16S rDNA gene amplification and sequencing) and intestinal barrier biomarkers—intestinal fatty acid-binding protein (I-FABP) and D-lactic acid (D-LA) (by ELISA and colorimetry, respectively). Plasma D-LA and I-FABP were significantly elevated in patients with OSA. The severity of OSA was related to differences in the structure and composition of the fecal microbiome. Enriched Fusobacterium, Megamonas, Lachnospiraceae_UCG_006, and reduced Anaerostipes was found in patients with severe OSA. Enriched Ruminococcus_2, Lachnoclostridium, Lachnospiraceae_UCG_006, and Alloprevotella was found in patients with high intestinal barrier biomarkers. Lachnoclostridium and Lachnospiraceae_UCG_006 were the common dominant bacteria of OSA and intestinal barrier damage. Fusobacterium and Peptoclostridium was independently associated with apnea–hypopnea index (AHI). The dominant genera of severe OSA were also related to glucose, lipid, neutrophils, monocytes and BMI. Network analysis identified links between the fecal microbiome, intestinal barrier biomarkers, and AHI. The study confirms that changes in the intestinal microbiota are associated with intestinal barrier biomarkers among patients in OSA. These changes may play a pathophysiological role in the systemic inflammation and metabolic comorbidities associated with OSA, leading to multi-organ morbidity of OSA. [ABSTRACT FROM AUTHOR]

Cornelia de Lange Syndrome (CdLS) is a rare genetic disorder, which causes a range of physical, cognitive, and medical challenges. To retrospectively analyze the clinical characteristics and genetic variations of Chinese patients, and to provide experience for further diagnosis and treatment of CdLS in Chinese children, we identified 15 unrelated Chinese children who presented with unusual facial features, short stature, developmental delay, limb abnormalities, and a wide range of health conditions. In this study, targeted-next generation sequencing was used to screen for causal variants and the clinically relevant variants were subsequently verified using Sanger sequencing. DNA sequencing identified 15 genetic variations, including 11 NIPBL gene variants, two SMC1A gene variants, one RAD21 gene variant, and one HDAC8 variant. The phenotype of these patients was summarized and differences between this cohort and another four groups were compared. The clinical manifestations of the patients in this cohort were mostly consistent with other ethnicities, but several clinical features in our cohort had different frequencies compared with other groups. We identified 15 deleterious variants of which 11 were novel. Variants in the NIPBL gene were the most common cause in our cohort. Our study not only expands upon the spectrum of genetic variations in CdLS, but also broadens our understanding of the clinical features of CdLS. [ABSTRACT FROM AUTHOR]

Pathogenic Escherichia coli can cause fatal diarrheal diseases in both animals and humans. However, no antibiotics or antimicrobial peptides (AMPs) can adequately kill resistant bacteria and clear bacterial endotoxin, lipopolysaccharide (LPS) which leads to inflammation and sepsis. Here, the LPS-targeted smart chimeric peptides (SCPs)-A6 and G6 are generated by connecting LPS-targeting peptide-LBP14 and killing domain-N6 via different linkers. Rigid and flexible linkers retain the independent biological activities from each component. SCPs-A6 and G6 exert low toxicity and no bacterial resistance, and they more rapidly kill multiple-drug-resistant E. coli and more effectively neutralize LPS toxicity than N6 alone. The SCPs can enhance mouse survival more effectively than N6 or polymyxin B and alleviate lung injuries by blocking mitogen-activated protein kinase and nuclear factor kappa-B p65 activation. These findings uniquely show that SCPs-A6 and G6 may be promising dual-function candidates as improved antibacterial and anti-endotoxin agents to treat bacterial infection and sepsis. Wang ZL and Wang XM design bactericidal peptides in which an antimicrobial domain is fused to a domain that facilitates the neutralisation of lipoplysaccaride (LPS) to prevent inflammation associated with the targeting of Gram-negative bacteria. They characterise their properties and structures, and show their efficiency in vitro and in vivo. [ABSTRACT FROM AUTHOR]

Transition metal sulfide nanoparticles provide efficient tumor photothermal therapy under near-infrared light, while suffering from poor chemical stability and biocompatibility. Protein scaffolds are attractive templates to fabricate various inorganic nanostructures, due to their inherent capabilities of molecular recognition and self-assembly characteristics. Herein, a straightforward method is demonstrated for efficiently synthesizing CuS nanoparticles inside the inner cavity of the genetically modified hepatitis B core protein virus-like particles (HBc VLPs) via the affinity of histidine tags to copper ions. The monodispersed and well-defined HBc-CuS VLPs have been yielded with high efficiency and used as a potential photothermal agent for cancer therapy due to their excellent photothermal conversion efficiency, high cellular uptake and biocompatibility. [ABSTRACT FROM AUTHOR]

NZ2114 is a promising candidate for therapeutic application owing to its potent activity to Staphylococcus aureus. Our objective was to identify NZ2114 derivatives with improved activity through substitution of His16 and His18 with residues Arginine and Lysine. Eight mutants were designed and expressed in Pichia pastoris X-33 via pPICZαA. Five of them exhibited strong antimicrobial activity against S. aureus at low minimal inhibitory concentrations (MICs) of 0.057-0.454 μM. Among them, H1, H2, and H3 showed ideal pharmacodynamic effects on methicillin-resistant S. aureus ATCC43300. The total protein level of H1, H2, and H3 reached 1.70, 1.77 and 1.54 g/l at 120 h of induction in the 5-l fermenter, respectively. They killed over 99.9% of pathogens within 1.5 h at 2× and 4× MIC. The post antibiotic effect of H1, H2 and H3 to S. aureus ATCC43300 was 2.94, 1.75 and 1.55 h at 2× MIC, which was similar with their original peptide NZ2114 (1.43 h) and vancomycin (1.72 h). The fractional inhibitory concentration index (FICI) indicated indifferent effects between H1, H2, H3 and vancomycin, ampicillin, rifampicin. Additionally, they had low hemolysis and high stability in different environments (temperature, pH, proteases, and saline ions). All results indicate that H1, H2, and H3 can be produced in large-scale and have potential as therapeutic drugs against MRSA. [ABSTRACT FROM AUTHOR]

NZ2114 is a promising candidate for therapeutic application owing to potent activity to gram-positive bacterium such as Streptococcus pneumoniae and Staphylococcus aureus. This work is the first report to describe the in vitro and in vivo antibacterial characteristics of NZ2114 against Streptococcus suis. It exhibited strong antimicrobial activity against S. suis type 2 strains CVCC 606, CVCC 3309, and CVCC 3928 at a low minimal inhibitory concentration (MIC) of 0.03-0.06 μM. The NZ2114 killed over 99.9% of tested S. suis CVCC 606 in Mueller-Hinton medium within 4 h when treated with 4 × MIC. It caused only less than 0.25% hemolytic activity in the concentration of 256 μg/ml. Additionally, NZ2114 exhibited potent in vivo activity to S. suis. All mice were survival when the dosage was low to 0.2 mg/kg. Over 99% of S. suis cells were killed within 4 h in blood, lung, liver and spleen with dosage of 10, 20, and 40 mg/kg in mice peritonitis models and no pathogen were detected after 24 h of treatment. Further, no pathological phenomenon in lung and low level of inflammatory cytokines in blood were detected. These results indicate that NZ2114 has the potential to be a new antimicrobial agent candidate for the clinical treatment of infection caused by S. suis type 2. [ABSTRACT FROM AUTHOR]

We present a three-dimensionally configured cathode with enhanced field-emission performance formed by combining carbon nanotube (CNT) emitters with a nickel foam (NiF) substrate via a conventional screen-printing technique. The CNT/NiF cathode has low turn-on electric field of 0.53 V μm (with current density of 10 μA cm) and threshold electric field of 0.87 V μm (with current density of 0.1 mA cm), and a very high field enhancement factor of 1.4 × 10. The porous structure of the NiF substrate can greatly improve the field-emission properties due to its large specific surface area that can accommodate more CNTs and increase the emitter density, as well as its high electrical and thermal conductivities that facilitate current transition and heat dissipation in the cathode. Most importantly, the local electric field was also enhanced by the multistage effect resulting from the rough metal surface, which furthermore leads to a high field enhancement factor. We believe that this improved field-emission performance makes such cathodes promising candidates for use in various field-emission applications. [ABSTRACT FROM AUTHOR]

Many different encoding algorithms for systematic polar codes (SPC) have been introduced since SPC was proposed in 2011. However, the number of the computing units of exclusive OR (XOR) has not been optimized yet. According to an iterative property of the generator matrix and particular lower triangular structure of the matrix, we propose an optimized encoding algorithm (OEA) of SPC that can reduce the number of XOR computing units compared with existing non-recursive algorithms. We also prove that this property of the generator matrix could extend to different code lengths and rates of the polar codes. Through the matrix segmentation and transformation, we obtain a submatrix with all zero elements to save computation resources. The proportion of zero elements in the matrix can reach up to 58.5% from the OEA for SPC when the code length and code rate are 2048 and 0.5, respectively. Furthermore, the proposed OEA is beneficial to hardware implementation compared with the existing recursive algorithms in which signals are transmitted bidirectionally. [ABSTRACT FROM AUTHOR]

As a large number of small base stations have been deployed in dense heterogeneous networks, the increasing cost of energy has become a challenging issue. In this paper, we propose an optimized clustering-based sleep strategy to release the power consumption and interference in the system. First, we group the small base stations with large interference as a cluster in which the binary particle swarm optimization (BPSO) algorithm is used to formulate a sleep strategy for small base stations in the clusters. Since the small base stations between clusters have less interference, the whole spectrum resources can be shared in all clusters and the orthogonal spectrum resources are allocated for the small base stations in the same cluster. The strategy effectively restrains the co-tier interference in the system. Furthermore, a separate sleep strategy is applied for each cluster to improve the sleep and activation efficiency of the small base stations. The simulation results show that the proposed sleep strategy can improve the satisfaction of user equipment and reduce the power consumption. As the increasing number of user equipment, the outage probability of the system can be reduced effectively. [ABSTRACT FROM AUTHOR]

Bovine lactoferricin (LfcinB) has potent antibacterial, antifungal and antiparasitic activities but is also hemolytic. Our objective was to identify LfcinB17-31 derivatives with reduced hemolysis and improved antimicrobial activity via substituting Cys3, Arg4, Gln7, Met10, and Gly14 with more hydrophobic residues. Two peptides, Lfcin4 and Lfcin5, showed higher activity against Staphylococcus aureus and Salmonella enteritidis and lower hemolytic activity than the parent peptide LfcinB17-31. These peptides permeabilized the outer and inner membranes of S. enteritidis; however, Lfcin5 did not permeabilize the inner membrane of S. aureus. Gel retardation and circular dichroism spectra showed that Lfcin4 and Lfcin5 bound to bacterial genomic DNA. Lfcin4 inhibited DNA, RNA and protein synthesis. Both peptides induced the peeling of membranes and the lysis of S. enteritidis. At doses of 10 and 15 mg/kg, Lfcin4 and Lfcin5 reduced the bacterial counts in infected thigh muscles by 0.03-0.10 and 0.05-0.63 log10 CFU/g of tissue, respectively, within 10 h. Lfcin4 and Lfcin5 enhanced the survival rate of endotoxemic mice; reduced serum IL-6, IL-1β and TNF-α levels; and protected mice from lipopolysaccharide-induced lung injury. These data suggest that Lfcin4 and Lfcin5 may be antimicrobial and anti-endotoxin peptides that could serve as the basis for the development of dual-function agents. [ABSTRACT FROM AUTHOR]