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Highlights • Extensively evaluate pixel-level image fusion based on CNN pedestrian detectors. • Study effective methods to combine pixel-level fusion and CNN-fusion architectures. • Three state-of-the-art CNN-based object detectors are evaluated. Abstract Vision-based pedestrian detection that can last all day is crucial in advanced driver-assistance systems (ADAS), autonomous vehicles and video surveillance. Based on the fact that the wavelength of human body radiation falls around 9.3 μm, thermal images have distinctive advantages for pedestrian detection in the nighttime. With the recent success of convolutional neural networks (CNNs) in the vision community, how to properly explore information in color and thermal images using CNNs-based methods attracts the attention of researchers. Previous CNN-based multispectral pedestrian detectors focus on the design of network architectures. The main contributions of this paper are as follows. First, pixel-level image fusion are also extensively evaluated based on a state-of-the-art CNNs-based framework in the daytime and nighttime for pedestrian detection. Second, the effective strategies to combine pixel-level fusion methods and CNN-fusion architectures are studied based on extensive experimental results. Two combination strategies are designed and an exhaustive experimental analysis is performed to evaluate different combinations for all-day pedestrian detection. Extensive results based on a multispectral pedestrian benchmark show that some pixel-level image fusion methods can achieve similar or even better performance than CNN-fusion architectures, which emphasizes the importance of pixel-level fusion in CNN-based pedestrian detectors. The combination of both can usually more properly exploit multispectral information and further boost detection performance. [ABSTRACT FROM AUTHOR]

Classification of traffic signs with partial occlusions is important for traffic sign maintenance and inventory systems. It is also important to help drivers identify possible traffic signs in time. Motivated by human cognitive processes in identifying an occluded sign, a novel structure is designed to explicitly handle occluded samples in this paper. Occlusion maps are analyzed for possible occluded signs, and a new occlusion descriptor is proposed to distinguish occluded signs from negative samples. A series of tests shows that the developed method could effectively handle samples with partial occlusions and thus reduce the missed detections caused by occlusions. The developed method could also be easily used for any other object detection. [ABSTRACT FROM PUBLISHER]

Reliable people counting and human detection is an important problem in visual surveillance. In recent years, the field has seen many advances, but the solutions have restrictions: people must be moving, the background must be simple, and the image resolution must be high. This paper aims to develop an effective method for estimating the number of people and locate each individual in a low resolution image with complicated scenes. The contribution of this paper is threefold. First, postprocessing steps are performed on background subtraction results to estimate the number of people in a complicated scene, which includes people who are moving only slightly. Second, an Expectation Maximization (EM)-based method has been developed to locate individuals in a low resolution scene. In this method, a new cluster model is used to represent each person in the scene. The method does not require a very accurate foreground contour. Third, the number of people is used as a priori for locating individuals based on feature points. Hence, the methods for estimating the number of people and for locating individuals are connected. The developed methods have been validated based on a 4-hour video, with the number of people in the scene ranging from 36 to 222. The best result for estimating the number of people has an average error of 10% over 51 test cases. Based on the estimated number of people, some results of the EM-based method have also been shown. [ABSTRACT FROM PUBLISHER]

The aim of the present study was to compare the characteristics of acellular dermal matrix (ADM), small intestinal submucosa (SIS) and Bio-Gide scaffolds with acellular vascular matrix (ACVM)-0.25% human-like collagen I (HLC-I) scaffold in tissue engineering blood vessels. The ACVM-0.25% HLC-I scaffold was prepared and compared with ADM, SIS and Bio-Gide scaffolds via hematoxylin and eosin (H&E) staining, Masson staining and scanning electron microscope (SEM) observations. Primary human gingival fibroblasts (HGFs) were cultured and identified. Then, the experiment was established via the seeding of HGFs on different scaffolds for 1, 4 and 7 days. The compatibility of four different scaffolds with HGFs was evaluated by H&E staining, SEM observation and Cell Counting Kit-8 assay. Then, a series of experiments were conducted to evaluate water absorption capacities, mechanical abilities, the ultra-microstructure and the cytotoxicity of the four scaffolds. The ACVM-0.25% HLC-I scaffold was revealed to exhibit the best cell proliferation and good cell architecture. ADM and Bio-Gide scaffolds exhibited good mechanical stability but cell proliferation was reduced when compared with the ACVM-0.25% HLC-I scaffold. In addition, SIS scaffolds exhibited the worst cell proliferation. The ACVM-0.25% HLC-I scaffold exhibited the best water absorption, followed by the SIS and Bio-Gide scaffolds, and then the ADM scaffold. In conclusion, the ACVM-0.25% HLC-I scaffold has good mechanical properties as a tissue engineering scaffold and the present results suggest that it has better biological characterization when compared with other scaffold types. [ABSTRACT FROM AUTHOR]

Enantiopure alcohols have received much attention due to their widespread use as pharmaceutical intermediates. In the asymmetric biosynthesis of enantiopure alcohols, the excellent performance of carbonyl reductase makes it be the best choice as the biocatalysts. In this work, an alkali-tolerant carbonyl reductase (BsCR, encoded by yueD) from Bacillus subtilis (strain 168) was obtained through gene mining, and successfully heterologously expressed in Escherichia coli with pET-32a. BsCR showed excellent alkali resistance and even can keep more than 70% of its peak activity after incubation in Tris–HCl buffer at pH 9.0 for 40 h. The Michaelis constants and maximal velocity of the BsCR to NADPH (A) and ethyl 4-chloroacetoacetate (B) are K m A = 5.390 × 10−2 mmol/L, K m B = 1.855 mmol/L, and V max = 147.3 μmol·min−1·mg−1, respectively. Applying the E. coli BL21(DE3)/pET-32a-yueD to catalyze asymmetric reduction of ethyl 4-chloroacetoacetate and acetophenone, the yield of S-CHBE reached 89.9% and S-1-phenyl ethanol reached 66.7%, and e.e. of both products reached more than 99%. This work provides a novel CR for asymmetric reduction. A carbonyl reductase (BsCR) and its gene were identified through gene mining, and overexpressed in Escherichia coli BL21(DE3) for whole-cell biocatalytic asymmetric reduction [ABSTRACT FROM AUTHOR]

Carbonyl reductase, as biocatalyst, is very important to chiral alcohols production through asymmetric reduction of carbonyl compound. A novel thermal stable carbonyl reductase from Bacillus cereus (BcCR) dependant on NADPH was obtained through a new genome mining strategy proposed in this work. By analyzing its amino acid sequence and structure, the BcCR should be a thermal stability and wide pH tolerance carbonyl reductase. Its gene was cloned by PCR with B. cereus genomic DNA as template. Its heterologous expression system, E. coli BL21 (DE3) plysS/pET28a-bccr, was constructed, and BcCR was successfully expressed. Enzymatic properties show that at 57.5 °C and pH 7.0 it can reach maximum reaction rate. Its Km and Vmax to ethyl 4-chloroacetoacetate is 1.85 mmol/L and 0.22 µmol/(min·mgprotein), respectively. It can catalyze the asymmetric reduction of the β-carbonyl compound, such as ethyl 4-chloroacetoacetate to ethyl S-4-chloro-3-hydroxybutyrate. This paper proposes a practical method for discovery of new carbonyl reductases, and provides a novel enzyme as biocatalyst for asymmetric reduction of β-carbonyl compound. [ABSTRACT FROM AUTHOR]

A real photonic crystal fibers (PCFs) evaluation approach based on compressed sensing with non-subsampled contourlet transform (NSCT) and the total variation model is proposed for modeling optical properties of the real PCFs. The classical images of a commercial large mode area PCF and polarization-maintaining PCF are used to verify the effectiveness of the proposed method. Experimental results demonstrate that the cross section images of real PCFs are rebuilt effectively by using only 36% image data for evaluating the optical properties with the same accuracy as by 100% data. To the best of our knowledge, this is the instance of applying the compressed sensing with the NSCT and total variation to reconstruct the cross section images of PCFs for quickly evaluating the optical properties of real PCFs without the requirement of long fiber samples and expensive measurement apparatuses. [ABSTRACT FROM AUTHOR]

Sulfonated graphene nanosheet/gold nanoparticle (SGN/Au) hybrid was synthesized by electrostatic self-assembly of anionic SGN and positively charged gold nanoparticles. Due to the well-dispersivity of SGN in aqueous solution and its adequate negative charge, Au nanoparticles were assembled uniformly on graphene surface with high distribution. With the advantages of both graphene and Au nanoparticles, SGN/Au hybrid showed enhanced electrocatalytic activity towards O reduction. Furthermore, it provided a conductive and favorable microenvironment for the glucose oxidase (GOD) immobilization and thus promoted its direct electron transfer at the glassy carbon electrode. Based on the consumption of O caused by glucose at the interface of GOD electrode modified with SGN/Au hybrid, the modified electrode displayed satisfactory analytical performance, including high sensitivity (14.55 μA mM cm), low detection limit (0.2 mM), an acceptable linear range from 2 to 16 mM, and also the prevention from the interference of some species. These results indicated that the prepared SGN/Au hybrid is a promising candidate material for high-performance glucose biosensor. [ABSTRACT FROM AUTHOR]

We describe a highly sensitive and selective amperometric sensor for the determination of nitrite. A glassy carbon electrode was modified with a composite made from gold nanoparticles (AuNPs) and sulfonated graphene (SG). The modified electrode displays excellent electrocatalytic activity in terms of nitrite oxidation by giving much higher peak currents (at even lower oxidation overpotential) than those found for the bare electrode, the AuNPs-modified electrode, and the SG-modified electrode. The sensor has a linear response in the 10 μM to 3.96 mM concentration range, a very good detection sensitivity (45.44 μA mM), and a lower detection limit of 0.2 μM of nitrite. Most common ions and many environmental organic pollutants do not interfere. The sensor was successfully applied to the determination of nitrite in water samples, and the results were found to be consistent with the values obtained by spectrophotometry. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Background: Acute kidney injury (AKI) is a common pathological process which occurs in hemorrhage, intoxication, etc. It has been shown that the lymphatic circulation plays an important regulatory role in the pathogenesis of hemorrhage shock, and that exogenous normal lymph (ENL) has a beneficial effect on multiple organ injuries. In the present study, we investigated the effect of ENL on lipopolysaccharide (LPS)-induced AKI in rats. Methods: The AKI was induced by the jugular vein injection of LPS (iv, 15 mg/kg). After 15 min of LPS injection, saline or ENL without cell components (5 mL/kg) was iv infused at the speed of 0.5 mL per minute. Then, the renal function indices in plasma and renal histomorphology, and the levels of P-selectin, intercellular adhesion molecule-1 (ICAM-1), myeloperoxidase (MPO) and Na+-K+-ATPase in renal tissue were assessed at 3 or 6 h after LPS injection. Results: LPS induced a severe kidney injury including increased levels of urea, creatinine in plasma, aggrandized activities of ICAM-1 and MPO in renal tissue, and decreased the Na+-K+-ATPase activity in renal cells. These deleterious effects of LPS were significantly ameliorated by ENL treatment. Conclusion: The present results indicate that ENL protect against LPS-induced AKI, suggesting an alternative therapeutic strategy for treatment of kidney injury accompanied with severe infection or sepsis. [ABSTRACT FROM AUTHOR]

Aim: To investigate the effect of exogenous normal lymph on kidney injury in disseminated intravascular coagulation (DIC) rats and to probe its mechanism. Methods: The DIC model was established by intravenous injection of Dextran 500. After 6 min, normal lymph without cell components was infused in the lymph group. After 40 min, the renal and coagulation function indices and renal histomorphology were observed. Results: Serum urea and creatinine in the model group were significantly higher than in the control and lymph groups. Renal morphological study showed red blood cell silting and casts forming in the model group. The prothrombin time (PT), prothrombin time ratio (PTR), activated partial thromboplastin time (APTT), and thrombin time of lymph and model groups were higher than those in the control group, whereas fibrinogen was lower. The PT, PTR, and APTT were prolonged in the lymph group than in the model group. The platelet functions of the lymph and model groups were higher than in the control group, but platelet aggregation rate and thrombosis-forming indices were lower than in the control group; the platelet adhesive and aggregation rates and thrombosis dry weight of the lymph group were lower than those of the model group. Conclusion: Exogenous normal lymph could alleviate kidney injury in DIC rats, which may be related to the improving coagulation function. [ABSTRACT FROM AUTHOR]

Fixation CO2with microalgae is a potential promising technique to reduce CO2emission for its various advantages. In this work, we develop a microalgal fixation CO2system to capture CO2from actual flue gas. At first, we evolved a strain Scenedesmus obliquus, named S. obliquusWUST4, with a UV mutagenesis technique, which can endure actual flue gas. The S. obliquusWUST4 can tolerate high concentration CO2, and possesses high CO2fixation ability. Then, we developed a pilot scale microalgal fixation CO2system to capture CO2from actual flue gas with the evolved S. obliquusWUST4. The flue gas was discharged from the combustion chamber in a coke oven. A 100 L air-lift photobioreactor was built in this system. In the pilot scale system, CO2can be captured from the actual flue gas by the S. obliquusWUST4. The CO2removal ratio can reach 67% with the optimal operation conditions. This provides an efficient technique for CO2capture. [ABSTRACT FROM AUTHOR]

Immune function disorders are common during acute renal failure (ARF), but the mechanisms are unknown. As the spleen is the largest organ of the immune system, we aimed to observe if there are morphological changes in the spleen in rabbits with ARF. In addition, we tried to explore its mechanism from the perspective of oxygen free radicals, nitric oxide (NO), myeloperoxidase (MPO), and membrane pump activities. ARF animal models were established by either hypodermic injection of 1.3 mL//kg bw 1%% HgCl2 or intramuscular injection of 10 mL//kg bw 50%% glycerin. Animals were divided into 12 h, 24 h, and 48 h treatment groups with six rabbits in each group. Compared with control animals, congestion was found in the spleen and splenic trabeculae were increased in the two ARF model groups at multiple time points. The malonaldehyde, NO, nitric oxide synthase, and MPO levels in the ARF models were increased compared with the control group at 24 h or 48 h, and the superoxide dismutase and adenosine triphosphatase activities were significantly lower than the levels in the control group at multiple time points. These indices of free radical damage were induced gradually with ARF development, and there were statistically significant differences at different time points. These data suggested that histological damage of spleen during ARF may lead to immune disorders, which might be related to free radical injury, NO excessive release, polymorphonuclear neutrophils (PMN) sequestration, and membrane pump dysfunction. [ABSTRACT FROM AUTHOR]

There is increasing evidence indicating that the distant organ injury is a major contributor of high mortality in patients subjected to acute renal failure (ARF). However, sources and mechanisms that ARF causes distant organ injury remain to be determined. The aim of this study is to explore the mechanism from polymorphonuclear neutrophil (PMN) sequestration and membrane pump suppression. To achieve this, we examined myeloperoxidase (MPO), a marker of PMN accumulation in tissues, and membrane pump activities of heart, pancreas, and kidney in two ARF rabbit models. Rabbits are randomly assigned to control, HgCl2-treated, and glycerin-treated groups. ARF animal models are established by hypodermic injection of 1% HgCl2 with 1.3 mL/kg bodyweight (bw) in HgCl2-treated group or intramuscular injection of 50% glycerin with 10 mL/kg bw in glycerin-treated group, respectively, and all animals in each group are further divided into 12 h, 24 h, and 48 h subgroups with each consisting of six rabbits. Six healthy rabbits serve as control group. Results have shown that MPO activities of kidney, myocardium, and pancreas in two model groups were significantly increased than control group at diverse time points. Membrane pump activities of kidney in two model groups are significantly lower than the control group at multiple time points. Moreover, Na+-K+-, Ca2+-, Mg2+-, and Ca2+-Mg2+-ATPase activities of myocardium and pancreas in two model groups are gradually declined with the development of ARF. These findings suggest that PMN sequestration and membrane pump suppression plays an important role in the pathogenesis of ARF and also a major mechanism of myocardium and pancreas injury during the process of ARF. [ABSTRACT FROM AUTHOR]

Background: The kidney is a common target in multiple organ dysfunction syndrome (MODS). The aim of this study is to determine the role of intestinal lymphatic pathway on renal injury in hemorrhagic shock rats. Methods: Wistar rats were divided into sham, shock, and ligation groups. The hemorrhagic shock model was induced in the shock and ligation groups. After resuscitation, the mesenteric lymph ducts were ligated in the ligation group. Blood from the carotid artery was taken to determine renal functional indices. The kidneys were used to observe histomorphological changes at 6 h after resuscitation. In addition, kidney homogenate was used to determine malondialdehyde (MDA), superoxide dismutase (SOD), tumor necrosis factor alpha (TNFα), interleukin-6 (IL-6), and myeloperoxidase (MPO) levels at 90 min after shock and 0, 1, 3, 6, 12, and 24 h after resuscitation. And the survival rate of 24 h was recorded. Results: The survival rate in shock group was obviously lower than sham and ligation groups. The urea and creatinine contents in the serum of shock and ligation groups were significantly higher than the sham group; the indices in the ligation group were significantly lower than the shock group. Histological studies showed various degrees of renal injury in the shock and ligation groups with a lesser severity in the ligation group. MDA, TNFα, IL-6, and MPO in renal homogenate of the shock group were raised, and the activity of SOD was lower in comparison to the sham group. Further, MDA, TNFα, IL-6, and MPO in renal homogenate of the ligation group at 6, 12, and 24 h were lower, and the SOD activity was higher than that of the shock group at the same time points. Conclusion: The mesenteric lymph duct ligation could be used to attenuate renal injury in shock rats. Its mechanism might be related to reducing the polymorph nuclear (PMN) and decreasing inflammatory mediator and free radical. [ABSTRACT FROM AUTHOR]

Background. Acute renal failure (ARF) is a common critical disorder. To decrease the mortality, it is important to prevent ARF from invading other organs in clinical setting. It is not known whether there is a dysfunction in pancreas during the pathogenesis of ARF. This study aimed to investigate the changes of morphology and function on pancreas in ARF rabbits. Methods. Sixty rabbits were randomly divided into four groups. The ARF model of groups 1 and 2 rabbits was established by hypodermic injection of 1% HgCl2 (1.3 mL/kg) and intramuscular injection of 50% glyceritum (10 mL/kg), respectively. The control groups 1 and 2 were injected with same volume of normal saline. After 24 hours, urea and creatinine contents and pancreatic amylase (AMY) activities in serum were measured using an automatic biochemical analyzer; the insulin levels were measured with radioimmunoassay method. Moreover, morphological alterations were examined by light microscopy; free radicals, nitric oxide (NO), and nitric oxide synthase (NOS) in pancreas homogenate were determined. Results. Morphological study showed that there were vacuolar degeneration and necrosis in pancreas of ARF for both groups 1 and 2. Compared with corresponding control group, the AMY activity was significantly elevated, whereas the INS values were decreased significantly in ARF groups 1 and 2. Malonaldehyde, NO, and NOS in pancreas homogenate were significantly increased, and superoxide dismutase activity was decreased. Conclusion. These data suggested that there were morphological damage of pancreas and disturbance of pancreatic secretion function in rabbits with ARF. Free radicals-injury and NO excessive release may explain the observed dysfunction. [ABSTRACT FROM AUTHOR]