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Humans have always played an important role in dispersing plants, animals, and other organisms—either intentionally or inadvertently. Over the last several decades, rapid developments in infrastructure and transportation have led to dramatic increases in trade, travel, and mass migration; this in turn has accelerated the human-mediated spread of organisms across the globe. In their new environments, introduced species may thrive and cause severe economic and ecological impacts. Mitigating the entry, establishment, and spread of exotic pests and pathogens is crucial for protecting agriculture, ecosystems, and people. To do this, it is important to understand the pathways by which invasive species spread, assess the associated risks, and develop effective mitigation measures. This chapter describes the role of risk analysis for understanding human-mediated pathways of pest introduction and spread and provides case studies from both the plant and animal health arenas.

Human immunodeficiency virus type 2 (HIV-2) accumulates fewer mutations during replication than HIV type 1 (HIV-1). Advanced studies of HIV-2 mutagenesis, however, have historically been confounded by high background error rates in traditional next-generation sequencing techniques. In this study, we describe the adaptation of the previously described maximum-depth sequencing (MDS) technique to studies of both HIV-1 and HIV-2 for the ultra-accurate characterization of viral mutagenesis. We also present the development of a user-friendly Galaxy workflow for the bioinformatic analyses of sequencing data generated using the MDS technique, designed to improve replicability and accessibility to molecular virologists. This adapted MDS technique and analysis pipeline were validated by comparisons with previously published analyses of the frequency and spectra of mutations in HIV-1 and HIV-2 and is readily expandable to studies of viral mutation across the genomes of both viruses. Using this novel sequencing pipeline, we observed that the background error rate was reduced 100-fold over standard Illumina error rates, and 10-fold over traditional unique molecular identifier (UMI)-based sequencing. This technical advancement will allow for the exploration of novel and previously unrecognized sources of viral mutagenesis in both HIV-1 and HIV-2, which will expand our understanding of retroviral diversity and evolution.

Summary The SUSD4 (Sushi domain-containing protein 4) gene encodes a complement inhibitor that is frequently deleted in 1q41q42 microdeletion syndrome, a multisystem congenital disorder that includes neurodevelopmental abnormalities. To understand SUSD4's role in the mammalian nervous system, we analyzed Susd4 knockout (KO) mice. Susd4 KO mice exhibited significant defects in motor performance and significantly higher levels of anxiety-like behaviors. Susd4 KO brain had abnormal “hairy” basket cells surrounding Purkinje neurons within the cerebellum and significantly reduced dendritic spine density in hippocampal pyramidal neurons. Neurons and oligodendrocyte lineage cells of wild-type mice were found to express Susd4 mRNA. Protein expression of the complement component C1q was increased in the brains of Susd4 KO mice. Our data indicate that SUSD4 plays an important role in neuronal functions, possibly via the complement pathway, and that SUSD4 deletion may contribute to the nervous system abnormalities in patients with 1q41q42 deletions., Graphical Abstract, Highlights • Susd4 is expressed in neurons and oligodendrocyte lineage cells • Susd4 knockout mice have abnormal hippocampal and cerebellar neuronal morphologies • Susd4 knockout mice exhibit anxiety-like behaviors and impaired motor function • Susd4 knockout mice have elevated brain levels of the complement component C1q, Behavioral Neuroscience; Cellular Neuroscience; Components of the Immune System; Neuroscience

Human immunodeficiency virus (HIV) mutagenesis is driven by a variety of internal and external sources, including the host APOBEC3 (apolipoprotein B mRNA editing enzyme catalytic polypetide-like 3; A3) family of restriction factors, which catalyze G-to-A transition mutations during virus replication. HIV-2 replication is characterized by a relative lack of G-to-A mutations, suggesting infrequent restriction by A3 proteins. To date, the activity of the A3 repertoire against HIV-2 has remained largely uncharacterized, and the mutagenic activity of these proteins against HIV-2 remains to be elucidated. In this study, we provide the first comprehensive characterization of the restrictive capacity of A3 proteins against HIV-2 in cell culture using a dual fluorescent reporter HIV-2 vector virus. We found that A3F, A3G, and A3H restricted HIV-2 infectivity in the absence of Vif and were associated with significant increases in the frequency of viral mutants. These proteins increased the frequency of G-to-A mutations within the proviruses of infected cells as well. A3G and A3H also reduced HIV-2 infectivity via inhibition of reverse transcription and the accumulation of DNA products during replication. In contrast, A3D, did not exhibit any restrictive activity against HIV-2, even at higher expression levels. Taken together, these results provide evidence that A3F, A3G, and A3H, but not A3D, are capable of HIV-2 restriction. Differences in A3-mediated restriction of HIV-1 and HIV-2 may serve to provide new insights in the observed mutation profiles of these viruses.

One of the requirements for the functionality of the AlGaN/GaN high-electron mobility transistors is the presence of a specific residual lattice strain in their active region. This lattice strain can be adjusted by depositing a multilayer stack that consists of individual Al x Ga 1 − x N layers with harmonized [Al]/[Ga] ratio, which produces a controlled depth gradient of the lattice misfit and consequently a controlled gradient of the residual lattice strain. However, the lattice misfit at the interfaces between adjacent layers is partially compensated by misfit dislocations and other microstructure features, e.g., V-shaped interfacial pyramids. In this contribution, a non-destructive method for simultaneous quantitative analysis of remaining lattice strains and density of microstructure defects compensating the lattice misfit is presented and illustrated on the example of AlGaN stacks with different composition profiles, which were deposited using metalorganic chemical vapor phase epitaxy on (111)-oriented Si wafers. This technique is based on the mapping of selected reciprocal lattice points using X-ray diffraction. The lattice strains obtained from the reciprocal space mapping were verified by confocal micro-Raman spectroscopy. The presence of the microstructure defects and the depth gradient of their density were confirmed by transmission electron microscopy. The interplay of the composition profile and the thickness of individual layers on the lattice strain is described by a micromechanical model. From the comparison of the experimental results with the lattice strains, which were predicted for a defect-free multilayer stack, the main strain relaxation mechanisms are concluded, and their impact on the strain relaxation is quantified.

A long-standing question of human immunodeficiency virus (HIV) genetic variation and evolution has been whether differences exist in mutation rate and/or mutation spectra among HIV types (i.e., HIV-1 versus HIV-2) and among HIV groups (i.e., HIV-1 groups M–P and HIV-2 groups A–H) and HIV-1 Group M subtypes (i.e., subtypes A–D, F–H, and J–K). To address this, we developed a new single-strand consensus sequencing assay for the determination of HIV mutation frequencies and spectra using the Illumina sequencing platform. This assay enables parallel and standardized comparison of HIV mutagenesis among various viral vectors with lower background error than traditional methods of Illumina library preparation. We found significant differences in viral mutagenesis between HIV types but intriguingly no significant differences among HIV-1 Group M subtypes. More specifically, HIV-1 exhibited higher transition frequencies than HIV-2, due mostly to single G-to-A mutations and (to a lesser extent) G-to-A hypermutation. These data suggest that HIV-2 RT exhibits higher fidelity during viral replication, and taken together, these findings demonstrate that HIV type but not subtype significantly affects viral mutation frequencies and spectra. These differences may inform antiviral and vaccine strategies.

Optical spectroscopic imaging of biological systems has important applications in medical diagnosis, biochemistry, and image-guided surgery. Vibrational spectroscopy, such as Raman scattering, provides high chemical selectivity but is limited by weak signals and a large fluorescence background. Fluorescence imaging is often used by introducing specific dyes in biological systems to label different system parts and to increase the image contrast. However, the extrinsic fluorescence of the staining molecules often masks the intrinsic vibrational signals of biomolecules, which could also be simultaneously detected using the same excitation laser source. Therefore, fluorescence staining is often accompanied by the loss of other important complimentary information. For example, the high laser power often used for the rapid, high-quality imaging could lead to photo-induced suppression or bleaching of the fluorescence and Raman signals resulting in sample photodamage. Therefore, simultaneous imaging and photodamage analysis need to be performed in a controlled bioimaging experiment. Here we perform simultaneous spectroscopic bioimaging and photostability analysis of rhodamine 6G (R6G) stained red blood cells (RBCs) using both fluorescence and resonance Raman imaging in a single 532 nm laser excitation experiment. We develop a corresponding data processing algorithm which allows separation of the two spectroscopic signals. We control the relative intensity of the R6G and RBC signals by varying the excitation laser power and simultaneously monitor the photostability of RBCs. We observe no significant photodamage of RBCs through the absence of changes in the relative Raman peak intensities. Conversely, the R6G molecules show bleaching with the suppression of both the fluorescence and resonance Raman signals. Our approach may be generalized to other types of stained cells with the appropriate selection of fluorescent dyes and excitation sources.

Feasibility of district heating networks for areas with low heat demand of passive and low energy houses implies the development of innovative concepts for the production, storage, distribution and supply of thermal energy. Low supply temperatures enables the use of heat from renewable and alternative sources, currently been neglected due to the usually high supply temperatures used in conventional district heating systems. Further on, low network temperatures are supporting the reduction of operational and investment costs. The paper describes the development of economically and ecologically optimized concepts for low temperature district heating networks using four representative case studies in Austria: Aktivpark Gussing, Seestadt Aspern, Winklweg Siedlung and Hummel Kaserne. The four case studies offered the possibility to investigate different supply and demand connection schemes and consequently deriving optimized scenarios taking into account local framework conditions, such as consumption and production settings and the related control strategies. The scenarios analysis is performed considering both economic and ecological issues. The results of the study show that the availability and economic conditions of low temperature heat sources is a key factor for facilitating LTDH networks. In rural areas, lower heat losses due to lower network temperatures are beneficiary for the LTDH network performance.

This article focuses on implementing multivariate analysis to evaluate biochar-derived carbonaceous nanomaterials (BCN) from three different feedstocks for the detection and differentiation of heavy metal ions in aqueous systems. The BCN were produced from dairy manure, rice straw and sorghum straw biochar using our NanoRefinery process. The NanoRefinery process transforms biochar into advanced nanomaterials using depolymerisation/chemical oxidation and purification of nanomaterials using solvent extraction. Dairy manure biochar-derived carbonaceous nanomaterials (DMB-CN), rice straw biochar-derived carbonaceous nanomaterials (RSB-CN) and sorghum straw biochar-derived carbonaceous nanomaterials (SSB-CN) were utilised as probes for the evaluation of their fluorescent properties and the detection of heavy metal ions. The BCN fluorescence quenching and fluorescence recovery was tested with lead (Pb2+), nickel (Ni2+), copper (Cu2+) and mercury (Hg2+). Principal component analysis (PCA) and discriminant analysis were used to differentiate among heavy metal ions in water samples. The BCN from different feedstocks had different characteristics and produced different interactions with heavy metal ions. DMB-CN had the highest quenching for Hg2+ and Ni2+ while SSB-CN and RSB-CN responded best to Cu2+ and Pb2+, respectively. The fluorescence quenching was modelled using linear and empirical functions. PCA and discriminant analysis used the quenching measurements to differentiate heavy metal ions in aqueous system. A key result was that the discriminant analysis had a 100% accuracy to detect Pb2+, 66% for Ni2+ and Cu2+, and 33% for Hg2+. This study has shown that biochar-derived carbonaceous nanomaterials could be used in heavy metal ions sensing applications. This is the first step in the development of a fast and accurate method for the detection of heavy metal ions in waters using environmentally friendly BCN.

This research seeks a coupled solution for managing the large amounts of biochar produced by microalgae biofuel production, and the necessity for novel, economic and accurate heavy metal sensing methods. Therefore, this study evaluated the transformation of microalgae biochar (MAB) into carbon dots (Cdots) and their subsequent application as heavy metal ion sensors in aqueous systems. The experimental phase included the transformation of MAB into microalgae biochar-derived carbon dots (MAB–Cdots), MAB–Cdot characterisation and the evaluation of the MAB–Cdots as transducers for the detection of four heavy metal ions (Pb2+, Cu2+, Cd2+, and Ni2+). MAB–Cdot fluorescence was stable over a wide range of pH and resistant to photo-bleaching, making them suitable as fluorescence probes. The MAB–Cdot fluorescence was quenched by all of the metal ions and displayed different quenching levels. Depending upon the ions involved, MAB–Cdots were used to detect the presence of heavy metal ions from concentrations of 0.012 μM up to 2 mM by measuring the reduction in fluorescence intensity. Neutral and slightly alkaline pHs were optimal for Cu2+ Ni2+ and Pb2+ heavy metal quenching. To quantify the concentration of the heavy metal ions, linear and logarithmic functions were used to model the MAB–Cdot fluorescence quenching. The sensing mechanism was determined to be reversible and purely collisional with some fluorophores less accessible than the others. This work demonstrated the ability to produce Cdots from microalgae biochar, examined their application as a transducer for detecting heavy metal ions in aqueous systems and paves the way for novel sensing systems using MAB-Cdots.

This article describes an efficient method, combining chemical oxidation and acetone extraction, to produce carbonaceous nanomaterials from dairy manure biochar. The optical and mechanical properties are similar to methods previously reported carbonaceous nanomaterials from biomass. Our novel process cuts the processing time in half and drastically reduces the energy input required. The acetone extraction produced 10 fractions with dairy manure biochar-derived carbonaceous nanomaterials (DMB–CNs). The fraction with the carbonaceous nanomaterials, DMB–CN-E1, with highest fluorescence was selected for in-depth characterisation and for initial testing across a range of applications. DMB–CN-E1 was characterised using atomic force microscope, electrophoresis, and spectrophotometric methods. DMB–CN-E1 exhibited a lateral dimension between 11 and 28 nm, a negative charge, and excitation/emission maxima at 337/410 nm, respectively. The bioimaging potential of DMB–CN-E1 evidenced different locations and different interactions with the cellular models evaluated. DMB–CN-E1 was quenched by several heavy metal ions showing a future application of these materials in heavy metal ion detection and/or removal. The demonstrated capabilities in bioimaging and environmental sensing create the opportunity for generating added-value nanomaterials (NanoRefinery) from dairy manure biochar gasification and, thus, increasing the economic viability of gasification plants.

It is demonstrated that hexagonal GaN can be obtained under ammonothermal conditions (125 MPa and 723 K) using Ba(NH2)2 as mineralizer. The hexagonal wurtzite-type GaN crystallites are several µm in diameter, as examined by scanning electron microscopy. This is to our knowledge the first successful ammonothermal GaN synthesis using an alkaline-earth metal as mineralizer. Ba[Ga(NH2)4]2 was identified as intermediate species in the ammonothermal synthesis process. The formation of h-GaN using Sr(NH2)2 as mineralizer was indicated only at higher temperatures above 1000 K.

Understanding the delivered cellular dose of nanoparticles is imperative in nanomedicine and nanosafety, yet is known to be extremely complex because of multiple interactions between nanoparticles, their environment, and the cells. Here, we use 3-D reconstruction of agglomerates preserved by cryogenic snapshot sampling and imaged by electron microscopy to quantify the "bioavailable dose" that is presented at the cell surface and formed by the process of individual nanoparticle sequestration into agglomerates in the exposure media. Critically, using 20 and 40 nm carboxylated polystyrene-latex and 16 and 85 nm silicon dioxide nanoparticles, we show that abrupt, dose-dependent "tipping points" in agglomeration state can arise, subsequently affecting cellular delivery and increasing toxicity. These changes are triggered by shifts in the ratio of the total nanoparticle surface area to biomolecule abundance, with the switch to a highly agglomerated state effectively changing the test article midassay, challenging the dose-response paradigm for nanosafety experiments. By characterizing nanoparticle numbers per agglomerate, we show these tipping points can lead to the formation of extreme agglomeration states whereby 90% of an administered dose is contained and delivered to the cells by just the top 2% of the largest agglomerates. We thus demonstrate precise definition, description, and comparison of the nanoparticle dose formed in different experimental environments and show that this description is critical to understanding cellular delivery and toxicity. We further empirically "stress-test" the commonly used dynamic light scattering approach, establishing its limitations to present an analysis strategy that significantly improves the usefulness of this popular nanoparticle characterization technique.

Alterations in ocular blood flow have been implicated in mechanisms that lead to vision loss in patients with various ocular disorders such as diabetic retinopathy, glaucoma, and age-related macular degeneration. Assessment of retinal and choroidal blood flow is also a window to evaluate systemic diseases that affect microvasculature. Quantification and qualification of the blood flow in the retina and choroid help us understand pathophysiology, stratify disease risk, and monitor disease progression in these disorders. Multiple methods are used by researchers for assessment of blood flow, but a gold standard is lacking. We review commonly used methods, both invasive and noninvasive, for evaluation of blood flow, including intravital microscopy, laser Doppler velocimetry, laser Doppler flowmetry, laser interferometry, confocal scanning laser Doppler flowmetry, laser speckle flowgraphy, Doppler optical coherence tomography, blue-field entoptic simulation, retinal vessel caliber assessment, optical coherence tomography angiography, retinal function imaging, color Doppler imaging, and scanning laser ophthalmoscope angiogram. As technology evolves, better evaluation of blood flow in various ocular and systemic diseases will likely bring new perspectives into clinical practice and translate to better diagnosis and treatment.

Human T-cell leukemia virus type 1 (HTLV-1) is the etiological agent of adult T-cell leukemia (ATL) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). HTLV-1 cell-to-cell transmission is dependent on the release of infectious virus particles into the virological synapse. The HTLV-1 particle structure is still poorly understood, and previous studies analyzed viruses produced by transformed lymphocytic cell lines chronically infected with HTLV-1, particularly the MT-2 cell line, which harbors truncated proviruses and expresses aberrant forms of the Gag protein. In this study, we demonstrate that the chronically infected SP cell line harbors a relatively low number of proviruses, making it a more promising experimental system for the study of the HTLV-1 particle structure. We first identified the genomic sites of integration and characterized the genetic structure of the gag region in each provirus. We also determined that despite encoding a truncated Gag protein, only the full-length Gag protein was incorporated into virus particles. Cryo-transmission electron microscopy analyses of the purified virus particles revealed three classes of particles based upon capsid core morphology: complete cores, incomplete cores, and particles without distinct electron densities that would correlate with the capsid region of a core structure. Observed cores were generally polygonal, and virus particles were on average 115 nm in diameter. These data corroborate particle morphologies previously observed for MT-2 cells and provide evidence that the known poor infectivity of HTLV-1 particles may correlate with HTLV-1 particle populations containing few virus particles possessing a complete capsid core structure. IMPORTANCE Studies of retroviral particle core morphology have demonstrated a correlation between capsid core stability and the relative infectivity of the virus. In this study, we used cryo-transmission electron microscopy to demonstrate that HTLV-1 particles produced from a distinct chronically infected cell line are polymorphic in nature, with many particles lacking organized electron densities that would correlate with a complete core structure. These findings have important implications for infectious HTLV-1 spread, particularly in the context of cell-to-cell transmission, a critical step in HTLV-1 transmission and pathogenesis.

The recombinant protein Ultrabithorax (Ubx), a Drosophila melanogaster Hox transcription factor, self-assembles into biocompatible materials in vitro that are remarkably extensible and strong. Here, we demonstrate that the strength of Ubx materials is due to intermolecular dityrosine bonds. Ubx materials auto-fluoresce blue, a characteristic of dityrosine, and bind dityrosine-specific antibodies. Monitoring the fluorescence of reduced Ubx fibers upon oxygen exposure reveals biphasic bond formation kinetics. Two dityrosine bonds in Ubx were identified by site-directed mutagenesis followed by measurements of fiber fluorescent intensity. One bond is located between the N-terminus and the homeodomain (Y4/Y296 or Y12/Y293), and another bond is formed by Y167 and Y240. Fiber fluorescence closely correlates with fiber strength, demonstrating that these bonds are intermolecular. To our knowledge, this is the first identification of specific residues that participate in dityrosine bonds in protein-based materials. The percentage of Ubx molecules harboring both bonds can be decreased or increased by mutagenesis, providing an additional mechanism to control the mechanical properties of Ubx materials. Duplication of tyrosine-containing motifs in Ubx increases dityrosine content in Ubx fibers, suggesting these motifs could be inserted in other self-assembling proteins to strengthen the corresponding materials.

The Pale di San Martino and Pale di San Lucano (referred to together as the “Pale”) are remnants of an originally more extensive carbonate platform in the Dolomite Mountains of northern Italy. The platforms are composed of Middle Triassic dolomites and limestones up to 1.6km thick. Limestones comprise 2–3% of the platform carbonates and are restricted to narrow corridors (tens to a few hundred metres wide, hundreds of metres long and high) within the dolomite. The mainly sucrosic dolomites of the Pale are interpreted as the result of recrystallization of a depositional, nearly stoichiometric Mg calcite under burial temperatures of ca. 40–70°C. The principal arguments are: The quantitative composition indicates that all platform carbonates are composed mainly of micritic crusts (45%; boundstone fabric prevails) and early cement (35%; microcrystalline, fibrous). The platform carbonates were probably mainly bacterial precipitates and tight at the sediment-water interface (porosities

Wood packaging material (WPM) is an important pathway for the spread of non-native plant pests. To reduce the likelihood of plant pest movement with WPM, the International Standard for Phytosanitary Measures No. 15: “Regulation of Wood Packaging Material in International Trade” (ISPM 15) was developed in the framework of the International Plant Protection Convention. To be compliant with this Standard, WPM shipped internationally must be either heat-treated or fumigated, regardless of any specific characteristics of the WPM. The objective of this survey was to determine if Bursaphelenchus xylophilus (Nematoda: Parasitaphelenchidae) or insects, especially Monochamus spp. (Coleoptera: Cerambycidae), were present in a specific subset of softwood boxes. While not compliant with ISPM 15, these boxes had been treated with wood preservatives, stored indoors for over five years, and, in addition to meeting various quality standards, almost all had a moisture content below 20 percent. United States Department of Agriculture staff inspected a sample of 630 softwood boxes, focusing on those showing signs of possible pest infestation. Based on a binomial distribution with an efficacy of detection equal to 0.95, a sample size of 630 provides a 95 percent confidence of detecting pests if >0.5 % of boxes are infested. No B. xylophilus or insect pests were found in the boxes, though other nematode genera (Aphelenchoides, Aphelenchus, and Filenchus), which feed on decomposing fungi in wood and do not damage trees, were found in 21 boxes. This study demonstrates that not all types of WPM present a high phytosanitary risk. It may be worthwhile to consider an amendment to ISPM 15 to differentiate between various risk categories of WPM in order to minimize costs and environmental impacts associated with treatments currently prescribed in ISPM 15. Prospection phytosanitaire de boites en bois de coniferes, en particulier pour le nematode du pin, Bursaphelenchus xylophilus (Nematoda: Parasitaphelenchidae) Le bois d'emballage est une filiere importante de dissemination des organismes nuisibles exotiques. Pour reduire le risque de presence d'organismes nuisibles aux vegetaux dans le bois d'emballage, la Norme Internationale pour les Mesures Phytosanitaires N°15: « Reglementation des materiaux d'emballage en bois utilises dans le commerce international » (NIMP 15) a ete developpee dans le cadre de la Convention Internationale pour la Protection des Vegetaux (CIPV). Pour etre en conformite avec cette norme, le bois d'emballage utilise dans les echanges internationaux doit obligatoirement etre traite par chauffage ou par fumigation, quelles que soient les caracteristiques de ce bois. L'objectif de cette etude etait de determiner si Bursaphelenchus xylophilus (Nematoda: Parasitaphelenchidae) ou des insectes, en particulier des Monochamus spp. (Coleoptera: Cerambycidae), etaient presents dans un lot precis de boites en bois de coniferes. Bien que n'etant pas conformes a la NIMP 15, ces boites avaient ete traitees avec des produits de conservation du bois, stockees en interieur pendant cinq ans, et avaient presque toutes une humidite relative inferieure a 20 pourcent, en plus de satisfaire plusieurs normes de qualite. Les inspecteurs de l'USDA ont controle un echantillon de 630 boites, en apportant une attention particuliere a celles qui presentaient les signes d'une infestation possible. En se basant sur une distribution binomiale avec une efficacite de la detection egale a 0,95, un echantillon de 630 boites permet de detecter une proportion de boites infestees ≥ a 0,5% avec un intervalle de confiance de 95%. Aucun B. xylophilus ou autres insectes nuisibles n'ont ete identifies dans les boites, bien que d'autres genres de nematodes (Aphelenchoides, Aphelenchus, et Filenchus) qui se nourrissent de champignon de decomposition du bois et ne nuisent pas aux arbres, ont ete trouves dans 21 boites. Cette etude demontre que tous les types de bois d'emballage ne presentent pas un risque phytosanitaire eleve. Il pourrait etre opportun d'envisager une modification de la NIMP 15 pour differencier les bois d'emballage selon des categories de risque different, afin de minimiser les couts et l'impact environnemental associe aux traitements actuellement requis par la NIMP 15. Oбcлeдoвaниe yпaкoвoчныx ящикoв из xвoйнoй дpeвecины нa нaличиe вpeдныx opгaнизмoв, в пepвyю oчepeдь cocнoвoй cтвoлoвoй нeмaтoды Bursaphelenchus xylophilus (Nematoda: Parasitaphelenchidae) Дpeвecный yпaкoвoчный мaтepиaл (ДУM) cлyжит вaжным пyтeм pacпpocтpaнeния чyжepoдныx вpeдныx для pacтeний opгaнизмoв. Для yмeньшeния вepoятнocти пepeнoca вpeдныx для pacтeний opгaнизмoв c ДУM, Meждyнapoдный cтaндapт пo фитocaнитapным мepaм № 15 «Peгyлиpoвaниe дpeвecнoгo yпaкoвoчнoгo мaтepиaлa в мeждyнapoднoй тopгoвлe» (MCФM 15) был paзpaбoтaн в paмкax Meждyнapoднoй Кoнвeнции пo кapaнтинy и зaщитe pacтeний. Для cooтвeтcтвия этoмy cтaндapтy пepeмeщaeмый мeждy cтpaнaми ДУM дoлжeн либo пpoйти тeплoвyю oбpaбoткy, либo быть пpoфyмигиpoвaнным, нeзaвиcимo oт eгo xapaктepиcтик. Цeлью нacтoящeгo иccлeдoвaния былo выяcнить, пpиcyтcтвyют ли Bursaphelenchus xylophilus (Nematoda: Parasitaphelenchidae) или нaceкoмыe, в ocoбeннocти Monochamus spp. (Coleoptera: Cerambycidae), в ocoбoй гpyппe ящикoв из xвoйнoй дpeвecины. Hecмoтpя нa тo, чтo oни нe cooтвeтcтвoвaли тpeбoвaниям MCФM 15, эти ящики были oбpaбoтaны кoнcepвaнтaми дpeвecины, xpaнилиcь в пoмeщeнии нa пpoтяжeнии бoлee пяти лeт, и, пoмимo cooтвeтcтвия paзличным cтaндapтaм кaчecтвa, пoчти вce имeли coдepжaниe влaги мeнee 20%. Пepcoнaл Дeпapтaмeнтa ceльcкoгo xoзяйcтвa Coeдинённыx Штaтoв дocмoтpeл oбpaзeц в 630 ящикoв из xвoйнoй дpeвecины, кoнцeнтpиpyяcь нa тex, кoтopыe имeли пpизнaки вoзмoжнoгo зapaжeния. Ocнoвывaяcь нa бинoмиaльнoм pacпpeдeлeнии c выявляeмocтью, paвнoй 0.95, paзмep oбpaзцa в 630 oбecпeчивaeт 95%-ный ypoвeнь эффeктивнocти выявлeния вpeдныx opгaнизмoв, ecли бoлee 0.5% ящикoв зapaжeны. Hи B. xylophilus, ни вpeдныe нaceкoмыe нe были нaйдeны в ящикax, xoтя дpyгиe poды нeмaтoд (Aphelenchoides, Aphelenchus и Filenchus), питaющиecя нa дepeвopaзpyшaющиx гpибax и нe вpeдящиe дepeвьям, были oбнapyжeны в 21 ящикe. Этo иccлeдoвaниe пoкaзывaeт, чтo нe вce типы ДУM пpeдcтaвляют выcoкий фитocaнитapный pиcк. Быть мoжeт, cлeдyeт cмoтpeть вoзмoжнocть cocтaвлeния пoпpaвки к MCФM 15, c тeм чтoбы диффepeнциpoвaть ДУM paзличныx кaтeгopий pиcкa c цeлью минимизиpoвaть зaтpaты и вoздeйcтвиe нa oкpyжaющyю cpeдy, oкaзывaeмoe тeми oбpaбoткaми, кoтopыe в нacтoящee вpeмя пpeдпиcывaютcя coглacнo MCФM 15.

Quantum Dots (QDs) stabilized with dihydrolipoic acid (DHLA) were used as a template for layer-by-layer (LbL) modification to study the effect on the QD optical properties. We studied several different polyelectrolytes to determine that large quantities of monodisperse DHLA-QDs could only be obtained with the weak polyelectrolyte pair of poly(allylamine hydrochloride) (PAH) and poly(acrylic acid) (PAA). The key to this success was the development of a two-step method to split the LbL process into adsorption and centrifugation phases, which require different pH solutions for optimum success. Solution pH is highlighted as an important factor to achieve sufficient QD surface coverage and QD recovery during wash cycles. We optimized the process to scale up synthesis by introducing a solvent precipitation step before ultracentrifugation that, when coupled with the correct pH conditions, results in a mean QD recovery of 86-90% after three wash cycles. We found that adsorption of PAH had a negligible effect on the quantum yield and lifetime but an additional layer of PAA resulted in a substantial decrease in both quantum yield and lifetime that could not be recovered by the addition of more layers. The PAH coating provides a protective coating that extends DHLA-QDs stability, prevents photo-oxidation mediated aggregation, alleviates concerns over batch variability, and results in pH-dependent emission.

For many years, valve-regulated lead–acid batteries with absorptive glass-mat (AGM) separator technology have been widely used in vehicles. Whereas the batteries were first fitted to luxury cars and special vehicles such as ambulances and taxis, the introduction of start–stop cars in Europe has opened the door for the global use of AGM batteries. The main advantage of the batteries is their excellent cycling performance at high depths-of-discharge due to a design that prevents acid stratification. On the road, a higher lifetime compared with conventional flooded batteries has been found. This feature, as predicted by laboratory tests, was successfully verified in early field trials with taxi fleets, even under elevated temperature conditions. AGM batteries are able to cope with the more demanding requirements of future vehicle applications, such as autonomous driving, due to their high reliability.

A half-scale three-bay by three-bay steel-concrete composite floor system, which represented gravity framing for a typical commercial building, was studied experimentally to evaluate its structural integrity under four separate column removal scenarios: a corner column, two edge columns, and an interior column. In each test, the load was incrementally applied in the bays that were tributary to the removed column using water in containers that were placed on top of the slab. The tests demonstrated that gravity systems for commercial buildings have a significant level of structural integrity—compared to the load redistribution capability expected for steel framing with simple shear connections—even without specific design against progressive collapse. In the corner and edge column removal scenarios, 2.9 kPa (60 psf) and 4.0 kPa (83 psf) were sustained, respectively, and these loads represent a range of 50–75% of the expected floor load. The interior column removal scenario had an unexpectedly low ca...

The pyrolytic decomposition of layered basic zinc acetate (LBZA) nanobelts (NBs) into nanocrystalline ZnO NBs is investigated using scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and photoluminescence (PL). We also report on the gas sensing response of the resulting ZnO nanomaterial to CO. The LBZA NBs are grown at 65 °C in an aqueous solution of zinc acetate dihydrate. AFM and SEM results show as-grown products possess the characteristic layered structure of the LBZA crystals. XRD and XPS results show that annealing as-grown products at 210 °C in air causes a transformation from zinc acetate to nanocrystalline ZnO NBs via thermal decomposition. The ZnO crystalline domain size increases with temperature from 9.2 nm at 200 °C to 94 nm at 1000 °C, as measured from XRD. SEM shows evidence of sintering at 600 °C. The thickness of the NBs, determined via AFM, ranges from 10 to 50 nm and remains approximately constant with annealing temperature. XPS confirmed the chemical transformation from zinc acetate to ZnO and showed a significant remaining zinc hydroxide component for the ZnO NBs consistent with published results. PL measurements at room temperature show a blue shift in peak emission as the nanobelts change from LBZA to ZnO at 200 °C. Above this transition temperature, the ZnO nanobelts possess strong band edge emission at 390 nm and little broad band emission in the visible region. The AFM and SEM images reveal that the crystallites within the nanobelts orientate in rows along the long axis during annealing. This structure provides a high surface area to volume ratio of aligned nanoparticles which is beneficial for gas sensing applications. Gas sensors fabricated from 400 °C annealed nanobelts showed a response of 1.62 when exposed to 200 ppm of CO in dry air at 400 °C, as defined by the ratio of resistance before and during exposure. This indicates that ZnO nanostructures obtained by thermal decomposition of LBZA NBs could provide a cost effective route to high sensitivity gas sensors.

Optical signals were used to modulate the resistance of single-walled carbon nanotube–polymer composite films for development of optical switching devices. Films were fabricated from nanotubes dispersed in poly(2-methoxy-5-(2′-ethylhexyloxy)-1,4-phenylenevinylene) (MEH-PPV) solutions in either tetrahydrofuran (THF) or toluene. MEH-PPV was affected by the solvent choice, with THF causing an absorbance shift to shorter wavelengths. Composite films formed from THF dispersions showed 1–4% resistance decreases when illuminated with a green diode laser. Illumination of toluene-based films showed up to 5.4% resistance decreases, smaller than expected based on the polymer solution absorbance. Fluorescent emission from the polymer in toluene appears to inhibit charge transfer from the polymer to the nanotubes. THF films were unaffected by illumination with a red diode laser, while toluene dispersion films showed resistance decreases up to 1%. Nanotube dispersion and film formation reproducibility, evaluated for both the solvents, showed that the solvent affected film resistance and dispersion stability.

We report a novel technique of directly coating colloidal CdSe/ZnS core/shell quantum dots (QDs) with silk fibroin (SF), a protein derived from the Bombyx mori silk worm. The approach results in protein-modified QDs with little or no particle aggregation, and mitigates the issue of biocompatibility. QDs have desirable optical properties, such as narrow-band emission, broadband absorption, high quantum yield, and high resistance to photobleaching. SF is a fibrous protein polymer with a biomimetic peptide sequence, water and oxygen permeability, low inflammatory response, no thrombogenecity, and cellular biocompatibility, which are desirable properties for in vivo delivery. Combining the unique properties of QDs with the biocompatibility profile of SF, the approach produces particles representing a powerful tool for numerous in vivo and in vitro applications. The design and preparation of these protein-modified QDs conjugates is reported along with functional characterization using luminescence, transmission electron microscope (TEM), and atomic force microscope (AFM). Additionally, we report results obtained using the QDs conjugates as a fluorescent label for bioimaging HEYA8 ovarian cancer cells.

Measurements and predictions are reported to understand large variations in evanescent wave (EW) scattering intensities between different particles from the same batch of single mode, polydisperse colloids. Measured EW scattering intensity distributions are obtained for three different micrometer sized latex particles irreversibly deposited onto glass surfaces. Predicted EW scattering intensity distributions are obtained using measured particle size distributions as input in a Mie theory for the three-dimensional scattering of a sphere under EW illumination. Good agreement is observed between measured and predicted EW scattering intensity distributions using no adjustable parameters. Our results indicate how finite polydispersity together with resonant effects produce large, nonlinear intensity variations between particles that appear to be physically and chemically uniform. Our findings allow such resonant effects to be understood and exploited in EW based particle-surface characterization techniques (e.g., using total internal reflections, surface plasmons) and chemical and biomolecular sensing applications (e.g., using whispering gallery modes).

To investigate the mechanism of interaction of gramicidin S-like antimicrobial peptides with biological membranes, a series of five decameric cyclic cationic beta-sheet-beta-turn peptides with all possible combinations of aromatic D-amino acids, Cyclo(Val-Lys-Leu-D-Ar1-Pro-Val-Lys-Leu-D-Ar2-Pro) (Ar identical with Phe, Tyr, Trp), were synthesized. Conformations of these cyclic peptides were comparable in aqueous solutions and lipid vesicles. Isothermal titration calorimetry measurements revealed entropy-driven binding of cyclic peptides to POPC and POPE/POPG lipid vesicles. Binding of peptides to both vesicle systems was endothermic-exceptions were peptides containing the Trp-Trp and Tyr-Trp pairs with exothermic binding to POPC vesicles. Application of one- and two-site binding (partitioning) models to binding isotherms of exothermic and endothermic binding processes, respectively, resulted in determination of peptide-lipid membrane binding constants (K(b)). The K(b1) and K(b2) values for endothermic two-step binding processes corresponded to high and low binding affinities (K(b1) >or= 100 K(b2)). Conformational change of cyclic peptides in transferring from buffer to lipid bilayer surfaces was estimated using fluorescence resonance energy transfer between the Tyr-Trp pair in one of the peptide constructs. The cyclic peptide conformation expands upon adsorption on lipid bilayer surface and interacts more deeply with the outer monolayer causing bilayer deformation, which may lead to formation of nonspecific transient peptide-lipid porelike zones causing membrane lysis.

Keys to successful treatment of disease include early diagnosis and timely treatment. It is hypothesized that early clotting events may contribute to a pro-thrombotic state that exacerbates atherothrombotic vascular disease. Brillouin spectroscopy involves inelastic coupling of light with phonons and enables viscoelastic characterization of samples at the microscale. In this work, we apply Brillouin spectroscopy to a model fibrinogen-thrombin clotting system with the goal of measuring clotting dynamics at the microscale and providing characterization that is not possible with standard rheometric techniques. Here, the clotting dynamics of the model clotting system are measured at various fibrinogen and thrombin concentrations.

Cross-system comparisons of drug delivery vectors are essential to ensure optimal design. An in-vitro experimental protocol is presented that separates the role of the delivery vector from that of its cargo in determining the cell response, thus allowing quantitative comparison of different systems. The technique is validated through benchmarking of the dose–response of human fibroblast cells exposed to the cationic molecule, polyethylene imine (PEI); delivered as a free molecule and as a cargo on the surface of CdSe nanoparticles and Silica microparticles. The exposure metrics are converted to a delivered dose with the transport properties of the different scale systems characterized by a delivery time, τ. The benchmarking highlights an agglomeration of the free PEI molecules into micron sized clusters and identifies the metric determining cell death as the total number of PEI molecules presented to cells, determined by the delivery vector dose and the surface density of the cargo.

The layer-by-layer modification of ≈5 nm mercaptocarboxylic acid stabilized gold nanoparticles was studied in an effort to illustrate effective means to overcome practical issues in handling and performing surface modification of such extremely small materials. To accomplish this, each layer deposition cycle was separated into a multi-step process wherein solution pH was controlled in two distinct phases of polyelectrolyte adsorption and centrifugation. Additionally, a solvent precipitation step was introduced to make processing more amenable by concentrating the sample and exchanging solution pH before ultracentrifugation. The pH-dependent assembly on gold nanoparticles was assessed after each layer deposition cycle by monitoring the plasmon peak absorbance location, surface charge, and the percentage of nanoparticles recovered. The selection of solution pH during the adsorption phase was found to be a critical parameter to enhance particle recovery and maximize surface charge when coating with weak polyelectrolytes. One bilayer was deposited with a high yield and the modified particles exhibited enhanced colloidal stability across a broad pH range and increased ionic strength. These findings support the adoption of this multi-step processing approach as an effective and generalizable approach to improve stability of high surface curvature particles.

Evanescent wave excited luminescence of quantum dot modified polystyrene (QDPS) colloids is investigated to measure potential energy profiles of QDPS colloids electrostatically levitated above a planar glass surface. Luminescence is characterized for three different-sized PS colloids modified with three different-sized QDs using confocal microscopy, emission spectra, flow cytometry, and temporal measurements of levitated and deposited colloids. Colloid-surface potential energy profiles constructed from scattering and luminescence intensity data display excellent agreement with each other, theoretical predictions, and independently measured parameters. QDPS luminescence intensity is indirectly confirmed to have an exponential dependence on height similar to conventional colloidal evanescent wave scattering. Our findings indicate that evanescent wave excited QDPS luminescence could enable total internal reflection microscopy measurements of index-matched hard spheres, multiple specific biomolecular interactions via spectral multiplexing, enhanced morphology-dependent resonance modes, and integrated evanescent wave-video-confocal microscopy experiments not possible with scattering.

the decentralised infiltration of rain water, which accumulates on sealed surfaces in urban areas, causes a change of the water balance parameters (evapotranspiration, surface run-off including sewage water and groundwater recharge) which in consequence leads to a rise of the groundwater level, in particular in areas with an increasing degree of surface sealing and low soil permeability. through adapted infiltration of rain water in combination with green roofs and rain water use systems, the impacts in new housing development areas can be controlled in such a way that the water balance – in particular the groundwater recharge – reaches its initial, pre-development level or that the groundwater returns to its natural level. the quantitative figures necessary for these control measures are provided by an area-differentiated water balance program whose input data can be determined by coupling various analytical and numerical simulation models. Due to proposed control measures in one urban housing development area, for example, Einfluss von Grundachern und Regenwassernutzungen auf Wasserhaushalt und Grundwasserstand in Siedlungen Patricia Gobel · Carsten Dierkes · Holger Kories · Johannes Meser · Erhard Meisner · Wilhelm G. Coldewey eingang des beitrages 26. 2. 2007 /eingang des uberarbeiteten beitrages: 8. 5. 2007 / Online veroffentlicht: 4. 7. 2007 10.1007/s00767-007-0032-y Dr. P. Gobel, Prof. Dr. W.G. coldewey Westfalische Wilhelms-Universitat Munster, Geologisch-Palaontologisches institut, Lehrstuhl fur angewandte Geologie corrensstr. 24, 48149 Munster e-Mail: pgoebel@uni-muenster.de, coldewey@uni-muenster.de Dr.-ing. c. Dierkes Hydrocon GmbH Mendelstr. 11, 48149 Munster e-Mail: dierkes@hydrocon.de Dipl.-Math. H. Kories DMt GmbH, bau consulting am technologiepark 1, 45307 essen e-Mail: holger.kories@dmt.de Dr. J. Meser Lippe Gesellschaft fur Wassertechnik mbH Hohenzollernstr. 50, 45128 essen e-Mail: messer@ewlw.de Dr.-ing. e. Meisner bayerisches Landesamt fur Umwelt burgermeister-Ulrich-Str. 160, 86179 augsburg e-Mail: erhard.meissner@lfu.bayern.de

Pyloromyotomy as described by Weber and Ramstedt has been the standard therapy for infantile hypertrophic pyloric stenosis since the 1960's and conservative therapy has been abandoned. The objective of this study was to test the effectiveness of systemic atropine applied intravenously for 7 days as a conservative therapeutic strategy and as an alternative to primary operation. Forty-two consecutive term infants with infantile hypertrophic pyloric stenosis were enrolled in the study over a period of 5 years. After confirmation of the diagnosis they all received intravenous atropine at a dose of 0.04 mg/(kg day) and increased by 0.01 mg/(kg day) up to 0.12 mg/(kg day), given as 6-8 single doses per/day. Nine pairs of parents requested that their child should be operated before completing the 7 days of medical therapy. Surgery was necessary in 8 of the remaining 33 infants (24,.2%) who did not improve after 7 days of conservative treatment. Successful treatment with i.v. atropine sulfate was achieved only in 25/33 term infants at an average maximal dose of 0.11 mg/(kg day), without any major side effects. Intravenous atropine sulfate has been considered as a potential alternative therapeutic strategy in the treatment of infantile hypertrophic pyloric stenosis. Clinical improvement however was often not seen before the 6th or 7th day of intravenous treatment. A success rate for the conservative approach of only 75% at day 7 in our study does not favour atropine therapy, in view of success rates above 95% with surgical repair.