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Tumor microenvironment and metabolic activity in gliomas are the important biomarkers to evaluate the progression of gliomas. Many evidences have suggested that the targeting of metabolic activity and tumor microenvironment simultaneously can be more effective to take the tumor therapy. Therefore, the noninvasive, accurate assessment of tumor microenvironment and metabolic activity is quite important in clinical practice. Multiphoton microscopy (MPM), based on two-photon-excited fluorescence and second harmonic generation was performed on unstained glioma tissues. With our combined image analysis approaches, our research findings indicate that MPM is able to qualitatively and quantitatively describe the microenvironment characteristics in gliomas, such as collage deposition in extracellular matrix, lymphocyte infiltration and tumor angiogenesis, etc. Meanwhile, the metabolic activity can also be quantitatively evaluated by optical redox ratio, NADH and FAD intensity. With the microendoscope and fiberscope are portable, MPM technique can be used to perform in-vivo studies and clinical examinations in gliomas.

Statistics describing different properties of each sequenced individual; Descriptions of blast results and gene annotation; Genetic diversity estimates of subsampled populations using neutral loci; The parameter scripts of BWA, SAMtools and VCFtools in this study

In order to ascertain impact of freshwater outflow from the Yangtze River on the gene flow of coastal species, the population genetic structure of mantis shrimps Oratosquilla oratoria in the East China Sea and Yellow Sea was analyzed by the partial mitochondrial DNA 16S rRNA gene. A total of 124 individuals from seven localities in the East China Sea and Yellow Sea were collected and 31 haplotypes were detected, giving an overall haplotype diversity of 0.8193 ± 0.0272 and nucleotide diversity of 0.0036 ± 0.0022. Two genetically divergent lineages were revealed, which displayed strong differences in the geographical distribution. Significant genetic differentiation between the East China Sea and Yellow Sea were also revealed by the results of AMOVA and pair-wise F ST . The present result supported our hypothesis that barrier effect of the Yangtze River outflow on gene flow of coastal species depend on differentiation salinity tolerance of species. It demonstrated that genetic pattern of O. oratoria in the East China Sea and Yellow Sea may be attributable to the interplay between salinity and the species’ life history traits.

This paper mainly investigated a looped tube refrigerator driven by a three-stage travelling wave thermoacoustic engine (later simply called as thermacoustic engine-refrigerator system). The onset and steady operation features of this coupling thermoacoustic system are analyzed through the network model developed by the author’s research group and the DeltaEC code, which is widely used in the thermacoustic research field. For power electronic thermal management utilizing low grade energy, a small scale three-stage travelling wave thermoacoustic engine-refrigerator system is designed. The onset features, steady performances and acoustic field features are analyzed in depth according to the simulation results. The analysis start with an investigation on the parametric sensitivity, followed by the description on the scaling and coupling impacts of this engine-refrigerator system on the onset temperature difference. The scaling impact is determined from the comparison results between a small scale and a large scale system, while the coupling impact is derived from the simulation of a refrigerator system and a simple engine system. The simulation results are also compared with the experimental data in publication, and the comparison demonstrated a desirable agreement. The main findings from this research work would provide some physical insights on the design and operating principles for the development of multi-stage thermoacoustic systems.

We used an extracellular pathogen Klebsiella pneumoniae to determine the role of NLRP12 (NOD-like receptor (NLR) family pyrin domain containing 12) as this bacterium is associated with devastating pulmonary infections. We found that human myeloid cells (neutrophils and macrophages) and non-myeloid cells (epithelial cells) show upregulation of NLRP12 in human pneumonic lungs. NLRP12-silenced human macrophages and murine Nlrp12(-/-) macrophages displayed reduced activation of nuclear factor-κB and mitogen-activated protein kinase, as well as expression of histone deacetylases following K. pneumoniae infection. NLRP12 is important for the production of interleukin-1β (IL-1β) in human and murine macrophages following K. pneumoniae infection. Furthermore, host survival, bacterial clearance, and neutrophil recruitment are dependent on NLRP12 following K. pneumoniae infection. Using bone marrow chimeras, we showed that hematopoietic cell-driven NLRP12 signaling predominantly contributes to host defense against K. pneumoniae. Intratracheal administration of either IL-17A+ CD4 T cells or chemokine (C-X-C motif) ligand 1 (CXCL1+) macrophages rescues host survival, bacterial clearance, and neutrophil recruitment in Nlrp12(-/-) mice following K. pneumoniae infection. These novel findings reveal the critical role of NLRP12-IL-17A-CXCL1 axis in host defense by modulating neutrophil recruitment against this extracellular pathogen.

The utilization of thermal insulation is one of the most effective methods to reduce the heating and cooling loss through building envelopes. However, moisture ingress driven by the pressure gradient across the insulation may lead to a variation of the effective thermal conductivity, which highly deteriorates the thermal performance of building envelopes. In order to investigate moisture transport mechanism and its impact on the heat transfer procedure, a novel simultaneous test method based on the modified guarded hot box is proposed to investigate the variations of the moisture content and the effective thermal conductivity of thermal insulation, besides, several possible visual identification methods are applied to analyze the moisture transport paths. Based on the proposed methods, both aerogel blanket and organic foam are investigated on the variations of hygrothermal properties. Results indicate that compared to the foam insulation, the moisture content has a greater impact on aerogel blankets with the thermal conductivity increase to 3 times of the initial values. Both scanning electron microscopy (SEM) combined with crystal tracer and magnetic resonance imaging (MRI) are utilized to identify the moisture transport paths of phenolic and polyisocyanurate foams. Pinholes and capillary channels are two main paths for liquid permeation into phenolic.

Borehole heat exchanger (BHE) is an important component in the ground coupled heat pump (GCHP) system. Based on the theories of composite medium line-source and the moving line-source, an analytical full time-scale model has been derived to predict the performance of BHE by considering the coupled effects of transient heat transfer in the borehole, the horizontal groundwater around the borehole and the axial heat conduction along the borehole. The full-scale model is validated by the experimental data and the numerical results. The validated model is applied to predict fluid temperature in the cases (i) with unit load, (ii) with annual building loads and (iii) with multiple boreholes. Based on the simulation results, the impacts of time length, axial conduction, groundwater flow and locations of boreholes are discussed in detail.

BackgroundThe enhancement of immunity is very important for immunocompromised patients such as cancer patients with radiotherapy or chemotherapy.Glycyrrhiza uralensishas been used as food and medicine for a long history.G. uralensispolysaccharides (GUPS) were prepared and its immunostimulatory effects were investigated.MethodsHuman monocyte-derived dendritic cells (DCs) and murine bone marrow-derived DCs were treated with different concentrations of GUPS. The DCs maturation and cytokine production were analyzed by flow cytometry and ELISA, respectively. Inhibitors and Western blot were used to study the mechanism of GUPS. The immunostimulatory effects of GUPS were further evaluated by naïve mouse model and immunosuppressive mouse model induced by cyclophosphamide.ResultsGUPS significantly promoted the maturation and cytokine secretion of human monocyte-derived DCs and murine bone marrow-derived DCs through TLR4 and down-stream p38, JNK and NF-κB signaling pathways. Interestingly, the migration of GUPS treated-DCs to lymph node was increased. In the mouse model, GUPS increased IL-12 production in sera but not for TNF-α. Moreover, GUPS ameliorated the side effect of cyclophosphamide and improved the immunity of immunosuppressive mice induced by cyclophosphamide. These results suggested that GUPS might be used for cancer therapy to ameliorate the side effect of chemotherapy and enhance the immunity.

Glycyrrhiza uralensis is a Chinese herbal medicine with various bioactivities. Three fractions (GUPS-I, GUPS-II and GUPS-III) of G. uralensis polysaccharides (GUPS) were obtained with molecular weights of 1.06, 29.1, and 14.9 kDa, respectively. The monosaccharide compositions of GUPS-II and GUPS-III were similar, while that of GUPS-I was distinctively different. The results of scanning electron microscopy, FT-IR, and NMR suggested that GUPS-II and GUPS-III were flaky with a smooth surface and contained &alpha, and &beta, glycosidic linkages, while GUPS-I was granulated and contained only &alpha, glycosidic linkages. Moreover, GUPS-II and GUPS-III exhibited better bioactivities on the maturation and cytokine production of dendritic cells (DCs) in vitro than that of GUPS-I. An in vivo experiment showed that only GUPS-II significantly enhanced the maturation of DCs. These results indicate that GUPS-II has the potential to be used in combination with cancer immunotherapy to enhance the therapeutic effect.

One fundamental problem of the convolutional neural network (CNN) is catastrophic forgetting, which occurs when new object classes and data are added while the original dataset is not available any more. Training the network only using the new dataset deteriorates the performance with respect to the old dataset. To overcome this problem, we propose an expanded network architecture, called the ExpandNet, to enhance the CNN incremental learning capability. Our solution keeps filters of the original networks on one hand, yet adds additional filters to the convolutional layers as well as the fully connected layers on the other hand. The proposed new architecture does not need any information of the original dataset, and it is trained using the new dataset only. Extensive evaluations based on the CIFAR −10 and the CIFAR −100 datasets show that the proposed method has a slower forgetting rate as compared to several existing incremental learning networks.

This paper aims to study the regulatory mechanism of circadian clock in cerebral ischemia reperfusion. It is investigated how well the sleeps of child patients with cerebral ischemia have been treated with neonates as study subjects. The core clock genes during the regulation of the circadian clock get explored by the bioinformatics methods. Here also analyzes pineal gland expression by combination with relevant technologies. The results reveal that the patients’ sleep quality has a stake in circadian rhythm and respiratory problems; the pineal gland can regulate the core clock genes in the circadian clock during the regulation. It is concluded that in relation to the treatment against ischemic diseases of neonates, sleep disorder and pineal function lesion require lucubrating to seek appropriate therapeutic regimen.

An efficient, scalable and robust approach to the handwritten digits recognition problem based on the Saak transform is proposed in this work. First, multi-stage Saak transforms are used to extract a family of joint spatial-spectral representations of input images. Then, the Saak coefficients are used as features and fed into the SVM classifier for the classification task. In order to control the size of Saak coefficients, we adopt a lossy Saak transform that uses the principal component analysis (PCA) to select a smaller set of transform kernels. The handwritten digits recognition problem is well solved by the convolutional neural network (CNN) such as the LeNet-5. We conduct a comparative study on the performance of the LeNet-5 and the Saak-transform-based solutions in terms of scalability and robustness as well as the efficiency of lossless and lossy Saak transforms under a comparable accuracy level., 5 pages, 5 figures, 5 tables

Gram-positive bacteria, including Staphylococcus aureus are endemic in the U.S., which cause life-threatening necrotizing pneumonia. Neutrophils are known to be critical for clearance of S. aureus infection from the lungs and extrapulmonary organs. Therefore, we investigated whether the NLRP6 inflammasome regulates neutrophil-dependent host immunity during pulmonary S. aureus infection. Unlike their wild-type (WT) counterparts, NLRP6 knockout (KO) mice were protected against pulmonary S. aureus infection as evidenced by their higher survival rate and lower bacterial burden in the lungs and extrapulmonary organs. In addition, NLRP6 KO mice displayed increased neutrophil recruitment following infection, and when neutrophils were depleted the protective effect was lost. Furthermore, neutrophils from the KO mice demonstrated enhanced intracellular bacterial killing and increased NADPH oxidase-dependent ROS production. Intriguingly, we found higher NK cell-mediated IFN-γ production in KO mouse lungs, and treatment with IFN-γ was found to enhance the bactericidal ability of WT and KO neutrophils. The NLRP6 KO mice also displayed decreased pyroptosis and necroptosis in the lungs following infection. Blocking of pyroptosis and necroptosis in WT mice resulted in increased survival, reduced bacterial burden in the lungs, and attenuated cytokine production. Taken together, these novel findings show that NLRP6 serves as a negative regulator of neutrophil-mediated host defense during Gram-positive bacterial infection in the lungs through regulating both neutrophil influx and function. These results also suggest that blocking NLRP6 to augment neutrophil-associated bacterial clearance should be considered as a potential therapeutic intervention strategy for treatment of S. aureus pneumonia., Author summary Gram-positive bacteria, including Staphylococcus aureus remain a major cause of acute pneumonia worldwide. Due to emergence of multidrug-resistant strains, alternative strategies for treatment of S. aureus pneumonia are needed. To this end, it may be possible to harness host defenses to eradicate the infection instead of directly targeting the bacteria. Neutrophils are a crucial innate immune cell type and serve as a first line of defense against bacterial lung infection. NLRP6 is a recently identified member of Nod-like receptor family. Nonetheless, the molecular and cellular immunological mechanisms by which the NLRP6 regulates neutrophil-mediated host immunity during acute S. aureus pneumonia remain elusive. We found that NLRP6 gene-deficient/knockout (KO) mice demonstrate increased survival and lower bacterial burden in the lungs along with enhanced neutrophil recruitment during acute S. aureus pneumonia. Moreover, neutrophils from NLRP6 KO mice showed increased bactericidal ability compared to those from controls. Similarly, NLRP6 KO mice demonstrated decreased cell death through pyroptosis and necroptosis following infection. Blocking of these cell death mechanisms in WT mice resulted in increased survival and decreased bacterial burden in the lungs following infection. Therefore, our study provides novel insights into the novel mechanisms mediated by NLRP6, which serves as a negative regulator of neutrophil-mediated host defense during Gram-positive pneumonia.

If we can find a new method that can achieve rapid diagnosis of adenoma during operation, it will help surgeon shorten the operation time and enhance the treatment efficacy. This study discusses the feasibility of multiphoton microscopy (MPM) in diagnosing pituitary adenoma. MPM, based on two-photon excited fluorescence (TPEF) and second harmonic generation (SHG) is performed for the diagnosis of pituitary adenoma in unstained sections. Our results show that MPM can reveal the variation of reticulin fiber by SHG signals of collagen, combined with the measurement of area of acinus, thickness of collagen fiber and collagen percentage. MPM can further reflect the change of meshwork in normal pituitary and hyperplasia quantitatively. And the characteristics of typical growth patterns of pituitary adenoma are demonstrated by the overlay of SHG and TPEF images. What’s more, we can identify the boundary of normal pituitary, hyperplasia and adenoma from MPM images. And the experiment also results verify the feasibility of this method in frozen sections. These results indicated that MPM can make a diagnosis of pituitary adenoma by the morphological changes without routine pathological processing including hematoxylin-eosin (H&E) staining and other special staining. Therefore, this technique is expected to help diagnosis of pituitary adenoma during operation.

When pipes are used for chilled water, glycol brines, refrigerants, and other chilled fluids, energy must be spent to compensate for heat gains through the wall of the pipes. Higher fluid temperature at the point of use decreases the efficiency of the end-use heat exchangers and increases the parasitic energy consumption. Mechanical pipe insulation systems are often used to limit the heat gains and save energy in commercial buildings. Pipe insulation systems play an important role for the health of the occupied space. When a chilled pipe is uninsulated or inadequately insulated, condensation might occur and water will drip onto other building surfaces, possibly causing mold growth. The critical issue with cold pipes is that the temperature difference between the pipe and its surrounding ambient air drives water vapor into the insulation system, and condensation commonly occurs when the water vapor comes in contact with the chilled pipe surface. This article, as the first part, experimentally studied this ...

The bifurcation method of dynamical system and numerical simulation method of differential equation are employed to investigate the (2+1)-dimensional Zoomeron equation. We obtain the parameter bifurcation sets that divide the parameter space into different regions which correspond to qualitatively different phase portraits. According to these phase portraits, all bounded traveling waves are identified and simulated, including solitary wave solutions, shock wave solutions, and periodic wave solutions. Furthermore, all exact expressions of these bounded traveling waves are given. Among them, the elliptic function periodic wave solutions are new solutions.

Along the coast of Shandong Province in China, an extensive hatchery-release programme has been conducted for more than 10 years. However, no information has been reported concerning the long-term effects on the wild population resulting from the release of large numbers of juveniles in Portunus trituberculatus. In this study, sequence variation of swimming crab P. trituberculatus based on the mitochondrial control region was investigated for 946 swimming crabs at the releasing sites from 2012 to 2014. The result showed that the wild P. trituberculatus was characterized by high genetic diversity indices, and not significantly different from the previous study. Low FST values were estimated among the groups of different years and different sites, which suggested no genetic differentiation found in the wild population after the stock enhancement programme. Hence, the long-term extensive hatchery release programme has not affected the genetic structure of wild P. trituberculatus populations along the coast of Shandong Province.

Advances in next-generation sequencing techniques have allowed for the generation of genome-wide sequence data, to gain insight into the dynamics influencing genetic structure and the local adaptation of marine fish. Here, using genotyping-by-sequencing (GBS) technique, we identified 31,119 single nucleotide polymorphisms (SNPs) for Sebastiscus marmoratus in 59 individuals from three populations in Chinese coastal waters. Based on all SNPs, there was little evidence of genetic differentiation among populations. However, outlier tests revealed 329 SNPs putatively under divergent selection across populations. Structural and phylogenetic topology analyses based on the outliers showed clear genetic differentiation among populations. Gene Ontology (GO) annotation results revealed that most of these outliers are known or hypothesized to be involved in metabolic process. Together with previous work using mitochondrial cytochrome b sequences, the present results further suggest that the population structure is strongly influenced by locally adaptive pressure. Overall, adaptive evolution in a heterogeneous environment plays an important role in inducing genetic differentiation among local populations. This study increases understanding of the factors (including gene flow and local adaptation) promoting and constraining population genetic differentiation in marine organisms.

Multiphoton microscopy was used to image gliomas without fluorescent dyes. Our results demonstrated that MPM is able to discern between normal tissue, tumor and necrosis. Several features significant for the diagnosis were clearly visualised.

Gama amino butyric acid (GABA) inhibition plays an important role in the onset and offset of the critical period for ocular dominance (OD) plasticity in the primary visual cortex. Previous studies have focused on the involvement of GABAA receptors, while the potential contribution of GABAB receptors to OD plasticity has been neglected. In this study, the GABAB receptor antagonist SCH50911 or agonist baclofen was infused into the primary visual cortex of cats concurrently with a period of monocular deprivation (MD). Using single-unit recordings we found that the OD shift induced by four days of MD during the critical period was impaired by infusion of the antagonist SCH50911, but enhanced by infusion of the agonist baclofen. In contrast, seven days of MD in adult cats did not induce any significant OD shift, even when combined with the infusion of SCH50911 or baclofen. Together, these findings indicate that an endogenous GABAB receptor-mediated inhibition contributes to juvenile, but not adult, OD plasticity.

Condensate that appears on mechanical pipe insulation systems might deteriorate the insulation thermal performance and lead to failure of the pipelines. An optimized solution that accounts for cost and system energy efficiency must consider the rate of moisture absorption at various operating conditions, and how the pipe insulation thermal conductivity varies with moisture content. This article reviews the most up-to-date work available in the public domain and observes that a controversy may exist about the similarities and differences of thermal conductivity of pipe insulation systems and flat slab configurations. Since the dissimilar behavior can be associated with the testing methodology from which the thermal conductivity values are originally derived, this article first discusses the methodologies for measuring thermal conductivity of pipe insulation systems with the intention of providing some clarification about such controversy. Steady-state and transient methods are discussed, and the measuremen...

MODIS Collection 5 land cover product (MCD12Q1) provides annually updated global land cover maps since 2001. This time series product has become an essential data source for the generation of many other land surface products and for a variety of regional and global studies. However, classification errors are inherent in the land cover product, which can misrepresent land cover transitions. In particular, land cover transitions are illogical if they contradict ecological rules and are unlikely to be observed. In this study, we evaluated the MODIS land cover product by analyzing the nature and magnitude of its illogical land cover transitions using annual MCD12Q1 land cover maps from 2001 to 2010. Our analysis revealed that illogical transitions exist in the product for all consecutive years, and are distributed most commonly in several regions over the world. To enhance the MODIS land cover product, we applied a spatial–temporal modeling algorithm that incorporates expert knowledge to reduce illogical transitions on five such “hotspot” tiles. The results showed substantial improvements in both accuracy and consistency of the land cover product using the spatial–temporal modeling algorithm. The percentage of illogical transitions in each of the five tiles was significantly reduced among consecutive years and across the entire time series. This study demonstrates the effectiveness of the spatial–temporal modeling algorithm for producing high quality time series of land cover maps, and also highlights the importance of temporal consistency in land cover mapping.

Lake eutrophication has become a very serious environmental problem in China. If water pollution is to be controlled and ultimately eliminated, it is essential to understand how human activities affect surface water quality. A recently developed technique using the Bayesian hierarchical linear regression model revealed the effects of land use and land cover (LULC) on stream water quality at a watershed scale. Six LULC categories combined with watershed characteristics, including size, slope, and permeability were the variables that were studied. The pollutants of concern were nutrient concentrations of total nitrogen (TN) and total phosphorus (TP), common pollutants found in eutrophication. The monthly monitoring data at 41 sites in the Xitiaoxi Watershed, China during 2009–2010 were used for model demonstration. The results showed that the relationships between LULC and stream water quality are so complicated that the effects are varied over large areas. The models suggested that urban and agricultural land are important sources of TN and TP concentrations, while rural residential land is one of the major sources of TN. Certain agricultural practices (excessive fertilizer application) result in greater concentrations of nutrients in paddy fields, artificial grasslands, and artificial woodlands. This study suggests that Bayesian hierarchical modeling is a powerful tool for examining the complicated relationships between land use and water quality on different scales, and for developing land use and water management policies.

Although electro-osmotic technique is common regeneration method of solid desiccant, it has the potential to be directly used as a dehumidification tool combined with the air-conditioning unit in the buildings. This paper proposes a novel dehumidification fin utilizing electro-osmotic effect. In order to further select the fin skeleton and design the structure of the dehumidification fin, this paper provides a series of fundamental work, which focus on the main factors related to the procedures of adsorption and electro-osmotic effect in different types of solid desiccant. Silica gel, activated alumina, zeolite and corresponding composite materials are the potential fin materials selected in this study. Two types of electro-osmotic dehumidification tests are designed to investigate the electro-osmotic behavior of solid desiccants in different degrees of saturation. Based on the experimental findings, the impacts of material type, particle size, voidage and electric field intensity are analyzed in detail in materials with different levels of saturation.

Schwannoma is a kind of slow-growing and rare neoplasm which poses diagnostic challenges owing to its clinical silence at the presentation period. Here, a schwannoma tumor was studied by multiphoton microscopy (MPM). Results indicate that MPM is capable of identifying a schwannoma tumor without the need for labels. Based on the two-photon excited fluorescence signals from cells and blood vessels and second harmonic generation signals from collagens, several significant features for the identification of schwannoma were visualized, including the Antoni A region, Antoni B region, pericellular collagen pattern, hyalinized vessels and hyalinized stroma. These conclusions highlight the potential of MPM taken as a diagnostic method for label-free identification of schwannoma tumors by these histopathologic characteristics.

Monocyte chemoattractant protein-1 (MCP-1) is important for monocyte recruitment to the lungs in response to bacterial infection. MCP-1 is also essential for neutrophil-dependent host defense during Escherichia coli infection. Carbapenem-Resistant Klebsiella pneumoniae (CRKP) infection has been rapidly growing as a life-threatening nosocomial disease in the U.S. and world. However, the role of chemokines and cellular responses in protective immunity to pulmonary infection with CRKP is largely unknown. Here, we investigated the role of MCP-1 in pulmonary host defense against CRKP infection using MCP-1 knockout (KO) mice. We determined survival, bacterial burden, and neutrophil influx, cytokine/chemokine expression as well as cellular functions, such as formation of neutrophil extracellular traps (NETs) and macrophage extracellular traps (METs). MCP-1 is essential for survival and restricting bacterial outgrowth organs. Compared to the C57Bl/6 (control) mice, KO mice showed impaired influx of neutrophils in the airways as assessed by nuclear cell morphology in BALF and by myeloperoxidase activity (MPO) in lung parenchyma. Moreover, the NETs and METs induced by CRKP were reduced in KO mice in both in vitro or in vivo. Intriguingly, subsequent to CRKP infection, KO mice demonstrated increased pyroptosis through enhanced activation of caspase-1, higher expression of IL-1β and cleaved gasdermin-D in the lungs. These findings enhance our understanding of the critical role of MCP-1 in modulating neutrophil function, such as NETosis, METosis and pyroptosis and suggest that therapies targeting modulation of NETs, METs and pyroptosis during CRKP infection can be explored through clinical trials.

Object-based classification has demonstrated numerous advantages over non-contextual pixel-based classification due to its capability of modelling spatial information through image segmentation. Similarly, contextual pixel-based classification can also incorporate spatial information among neighbouring pixels to improve the performance of non-contextual pixel-based classification. However, to our knowledge, no study has compared object-based approaches with contextual pixel-based approaches for image classification. In this letter, we compared an object-based approach using a segmentation algorithm embedded in eCognition with a contextual pixel-based approach using Markov random fields. The performances were evaluated with a high spatial resolution image (3 m) and a medium spatial resolution image (30 m) using various thematic and geometric accuracy indices. The results showed that the classification accuracy of the contextual pixel-based approach is higher than the object-based approach on both images, a...

[1] The major increase in atmospheric methane (CH4) concentration during the last glacial-interglacial transition provides a useful example for understanding the interactions and feedbacks among Earth's climate, biosphere carbon cycling, and atmospheric chemistry. However, the causes of CH4 doubling during the last deglaciation are still uncertain and debated. Although the ice-core data consistently suggest a dominant contribution from northern high-latitude wetlands in the early Holocene, identifying the actual sources from the ground-based data has been elusive. Here we present data syntheses and a case study from Alaska to demonstrate the importance of northern wetlands in contributing to high atmospheric CH4 concentration in the early Holocene. Our data indicate that new peatland formation as well as peat accumulation in northern high-latitude regions increased more than threefold in the early Holocene in response to climate warming and the availability of new habitat as a result of deglaciation. Furthermore, we show that marshes and wet fens that represent early stages of wetland succession were likely more widespread in the early Holocene. These wetlands are associated with high CH4 emissions due to high primary productivity and the presence of emergent plant species that facilitate CH4 transport to the atmosphere. We argue that early wetland succession and rapid peat accumulation and expansion (not simply initiation) contributed to high CH4 emissions from northern regions, potentially contributing to the sharp rise in atmospheric CH4 at the onset of the Holocene.

Temporal trajectories of land-cover change provide important information on landscape dynamics that are critical to our understanding of complex human–environment adaptive systems. The increasing availability of long time series of satellite images, especially the recent free release of multi-decadal Landsat satellite archive, presents a great opportunity to improve our ability to detect land-cover change over multiple dates and advance land change science. In this article, a spatial-temporal modeling approach is developed for reconstructing land-cover change trajectories from time series of satellite images. The change detection method represents an enhancement to the conventional post-classification comparison. The key innovation lies in the use of Markov random field theory to model spatial-temporal contextual information explicitly in the classification of time series images. When evaluated using a time series of seven Landsat images in a case study of southeast Ohio, the spatial-temporal modeling app...

Abandoned underground mines (AUM) have caused dramatic environmental effects that are closely linked to regional sustainability. This paper explores the potential hydrological impact of AUM in the Monday Creek Watershed, a typically mined area in Appalachian region, using the Soil and Water Assessment Tool (SWAT 2005) model and Sequential Uncertainty Fitting (SUFI-2), calibrated at both the global and local scales. The locally calibrated model better incorporates those key parameters relevant to AUM for specific sub-basins and hydrologic response units. Data from the years 2003–2004 were used for calibration and 2005–2006 for validation. The results were quite satisfactory; both the coefficient of determination (R2) and the Nash–Sutcliffe efficiency statistic were over 0.80. The potential influences of AUM were assessed by modelling an alternative scenario assuming no AUM for the period 2003–2009. Results show that the hydrological process of lateral subsurface flow plays a dominant role in linking AUM to overall watershed hydrology. The potential hydrological impact of AUM is an increased annual lateral flow of 82.1%, and a decrease in annual surface flow by 15%, leading to an increase of 16.9% in annual water yield for the Monday Creek Watershed. The seasonal fluctuation of water yield has a similar trend to lateral flow, decreasing from March to August and increasing from August to January. Higher volume, higher flow peaks and higher recession constants characterized the hydrograph of daily streamflow from AUM. The results indicate that more emphasis should be put on lateral flow for further study of acid mine drainage and flooding control in those watersheds with AUM. Copyright © 2012 John Wiley & Sons, Ltd.

Chronic obstructive pulmonary disease (COPD) is the third leading cause of mortality in the United States. The major cause of COPD is cigarette smoking. Extensive leukocyte influx into the lungs, mediated by chemokines, is a critical event leading to COPD. Although both resident and myeloid cells secrete chemokines in response to inflammatory stimuli, little is known about the role of epithelial-derived chemokines, such as CXC chemokine ligand (CXCL)5, in the pathogenesis of cigarette smoke-induced inflammation. To explore the role of CXCL5, we generated CXCL5 gene-deficient mice and exposed them to secondhand smoke (SHS) for 5 hours/day for 5 days/week up to 3 weeks (subacute exposure). We observed a reduced recruitment of leukocytes to the lungs of CXCL5(-/-) mice compared with their wild-type (WT) counterparts, and noted that macrophages comprised the predominant leukocytes recruited to the lungs. Irradiation experiments performed on CXCL5(-/-) or WT mice transplanted with WT or CXCL5(-/-) bone marrow revealed that resident but not hematopoietic cell-driven CXCL5 is important for mediating SHS-induced lung inflammation. Interestingly, we observed a significant reduction of monocyte chemotactic protein-1 (MCP-1/CC chemokine ligand 2) concentrations in the lungs of CXCL5(-/-) mice. The instillation of recombinant MCP-1 in CXCL5(-/-) mice reversed macrophage recruitment. Our results also show the reduced activation of NF-κB/p65 in the lungs, as well as the attenuated activation of C-Jun N-terminal kinase, p42/44, and p38 mitogen-activated protein kinases and the expression of intercellular adhesion molecule-1 in the lungs of SHS-exposed CXCL5(-/-) mice. Our findings suggest an important role for CXCL5 in augmenting leukocyte recruitment in SHS-induced lung inflammation, and provide novel insights into CXCL5-driven pathogenesis.

Bacterial pneumonia remains a significant cause of mortality in the United States. The innate immune response is the first line of defense against invading bacteria. Neutrophil recruitment to the lungs is the first step in a multistep sequence leading to bacterial clearance. Ligand interaction with pattern-recognizing receptors (PRRs) leads to chemokine production, which drives neutrophils to the site of infection. Although we demonstrated that RIP2 is important for host defense in the lungs against Escherichia coli , the individual roles of NOD1 and NOD2 in pulmonary defense have not been addressed. Here, we explored the role of NOD2 in neutrophil-mediated host defense against an extracellular pathogen, E. coli . We found enhanced bacterial burden and reduced neutrophil and cytokine/chemokine levels in the lungs of NOD2 −/− mice following E. coli infection. Furthermore, we observed reduced activation of NF-κB and mitogen-activated protein kinases (MAPKs) in the lungs of NOD2 −/− mice upon E. coli challenge. Moreover, NOD2 −/− neutrophils show impaired intracellular bacterial killing. Using NOD2/RIP2 −/− mice, we observed bacterial burden and neutrophil accumulation in the lungs similar to those seen with NOD2 −/− mice. In addition, bone marrow-derived macrophages obtained from NOD2/RIP2 −/− mice demonstrate a reduction in activation of NF-κB and MAPKs similar to that seen with NOD2 −/− mice in response to E. coli . These findings unveil a previously unrecognized role of the NOD2-RIP2 axis for host defense against extracellular Gram-negative bacteria. This pathway may represent a novel target for the treatment of lung infection/inflammation.

Bacterial flagellin is critical to mediate NLRC4 inflammasome-dependent caspase-1 activation. However, Shigella flexneri, a nonflagellated bacterium, and a flagellin (fliC) knockout strain of Pseudomonas aeruginosa are known to activate NLRC4 in bone marrow-derived macrophages. Furthermore, the flagellin-deficient fliC strain of P. aeruginosa was used in a mouse model of peritonitis to show the requirement of NLRC4. In a model of pulmonary P. aeruginosa infection, flagellin was shown to be essential for the induction of NLRC4-dependent caspase-1 activation. Moreover, in all P. aeruginosa studies, IL-1β production was attenuated in NLRC4−/− mice; however, the role of IL-1β in NLRC4-mediated innate immunity in the lungs against a nonflagellated bacterium was not explored. In this article, we report that NLRC4 is important for host survival and bacterial clearance, as well as neutrophil-mediated inflammation in the lungs following Klebsiella pneumoniae infection. NLRC4 is essential for K. pneumoniae-induced production of IL-1β, IL-17A, and neutrophil chemoattractants (keratinocyte cell-derived chemokines, MIP-2, and LPS-induced CXC chemokines) in the lungs. NLRC4 signaling in hematopoietic cells contributes to K. pneumoniae-induced lung inflammation. Furthermore, exogenous IL-1β, but not IL-18 or IL-17A, partially rescued survival, neutrophil accumulation, and cytokine/chemokine expression in the lungs of NLRC4−/− mice following infectious challenge. Furthermore, IL-1R1−/− mice displayed a decrease in neutrophilic inflammation in the lungs postinfection. Taken together, these findings provide novel insights into the role of NLRC4 in host defense against K. pneumoniae infection.

In prior studies, we demonstrated that 1) CXCL1/KC is essential for NF-κB and MAPK activation and expression of CXCL2/MIP-2 and CXCL5/LPS-induced CXC chemokine in Klebsiella-infected lungs, and 2) CXCL1 derived from hematopoietic and resident cells contributes to host immunity against Klebsiella. However, the role of CXCL1 in mediating neutrophil leukotriene B4 (LTB4), reactive oxygen species (ROS), and reactive nitrogen species (RNS) production is unclear, as is the contribution of these factors to host immunity. In this study, we investigated 1) the role of CXCL1 in LTB4, NADPH oxidase, and inducible NO synthase (iNOS) expression in lungs and neutrophils, and 2) whether LTB4 postinfection reverses innate immune defects in CXCL1−/− mice via regulation of NADPH oxidase and iNOS. Our results demonstrate reduced neutrophil influx, attenuated LTB4 levels, and decreased ROS and iNOS production in the lungs of CXCL1−/− mice after Klebsiella pneumoniae infection. Using neutrophil depletion and repletion, we found that neutrophils are the predominant source of pulmonary LTB4 after infection. To treat immune defects in CXCL1−/− mice, we intrapulmonarily administered LTB4. Postinfection, LTB4 treatment reversed immune defects in CXCL1−/− mice and improved survival, neutrophil recruitment, cytokine/chemokine expression, NF-κB/MAPK activation, and ROS/RNS production. LTB4 also enhanced myeloperoxidase, H2O2, RNS production, and bacterial killing in K. pneumoniae-infected CXCL1−/− neutrophils. These novel results uncover important roles for CXCL1 in generating ROS and RNS in neutrophils and in regulating host immunity against K. pneumoniae infection. Our findings suggest that LTB4 could be used to correct defects in neutrophil recruitment and function in individuals lacking or expressing malfunctional CXCL1.

Recognition of microbial patterns by host receptors is the first step in a multistep sequence leading to neutrophil-dependent host resistance. Although the role of membrane-bound sensors in bacterial recognition has been examined in detail, the importance of cytosolic sensors in the lungs is largely unexplored. In this context, there is a major lack of understanding related to the downstream signaling mediators, such as cells and/or molecules, during acute extracellular Gram-negative bacterial pneumonia. In order to determine the role of NOD-like receptors (NLRs), we used an experimental Escherichia coli infection model using mice deficient in the gene coding for the NLR adaptor, receptor-interacting protein 2 (RIP2). RIP2 −/− mice with E. coli infection displayed higher bacterial burden and reduced neutrophil recruitment and tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6), macrophage inflammatory protein 2 (MIP-2), and CXCL5/LIX expression, along with attenuated histopathological changes in the lungs. Decreased IL-17A levels were observed, along with lower numbers of IL-17A-producing T cells, in RIP2 −/− mice after infection. RIP2 −/− mice also show reduced IL-6 and IL-23 levels in the lungs, along with decreased activation of STAT3 after infection. Furthermore, activation of NF-κB and mitogen-activated protein kinases (MAPKs) and expression of intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) in the lungs of infected RIP2 −/− mice were attenuated following infection. Although neutrophil mobilization to the blood was impaired in RIP2 −/− mice following infection, the expression of CD62P, CD11a/18, CD11b, and CXCR2 on blood and lung neutrophils was not altered between infected wild-type (WT) and RIP2 −/− mice. Thus, RIP2 contributes to neutrophil-dependent host defense against an extracellular Gram-negative pathogen via (i) IL-17A regulation and (ii) neutrophil mobilization to the blood.

Studying boreal-type peatlands near the edge of their southern limit can provide insight into responses of boreal and sub-arctic peatlands to warmer climates. In this study, we investigated peatland history using multi-proxy records of sediment composition, plant macrofossil, pollen, and diatom analysis from a 14C-dated sediment core at Tannersville Bog in northeastern Pennsylvania, USA. Our results indicate that peat accumulation began with lake infilling of a glacial lake at ~ 9 ka as a rich fen dominated by brown mosses. It changed to a poor fen dominated by Cyperaceae (sedges) and Sphagnum (peat mosses) at ~ 1.4 ka and to a Sphagnum-dominated poor fen at ~ 200 cal yr BP (~ AD 1750). Apparent carbon accumulation rates increased from 13.4 to 101.2 g C m− 2 yr− 1 during the last 8000 yr, with a time-averaged mean of 27.3 g C m− 2 yr− 1. This relatively high accumulation rate, compared to many northern peatlands, was likely caused by high primary production associated with a warmer and wetter temperate climate. This study implies that some northern peatlands can continue to serve as carbon sinks under a warmer and wetter climate, providing a negative feedback to climate warming.