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Hydrogels, typically favored for 3D printing due to their viscoelasticity, are now trending toward ecofriendly alternatives amid growing environmental concerns. In this study, we crafted cellulose-based hydrogels, specifically employing cellulose acetate sulfate (CAS). By keeping the acetyl group substitution degree (DSacetyl= 1.8) and CAS molecular weight constant, we varied rheological properties by adjusting sulfate group substitution (DSsulfate= 0.4, 0.7, and 1.0) and CAS concentration (2–5 wt %). Rheological characterizations, including shear-thinning, yield stress, and thixotropy, were performed to identify optimal conditions for formulating CAS hydrogel ink in direct ink writing for 3D printing under selected experimental conditions. Based on rheological findings, CAS hydrogels with DSsulfate0.7 and concentration of 4 wt % was used for 3D printing, with subsequent evaluation of printing metrics. Additionally, the effect of ionic cross-linking using Ca2+ions on the structural integrity of 3D-printed structures was evaluated, demonstrating effective preservation through reinforced polymer networks. The shrinking and swelling behaviors of the 3D-printed structures were also significantly affected by this ionic cross-linking. Building on these findings, this work could broaden the range of cellulose derivatives available for the preparation of cellulose-based hydrogels for 3D printing.

Solid-phase microextraction (SPME) coupled with gas chromatography–mass spectrometry (GC–MS) analysis was used for the at-line sampling of pyrolytic vapors produced during the fast pyrolysis of biomass. The pure and binary blends of switchgrass (SWG) and pine harvest residues (PT6) were used as biomass feedstocks. Sequential SPME sampling allowed for monitoring of changes in the pyrolysis vapors as char accumulated in the fluid bed. The relative concentration and composition of the pyrolysis vapors desorbed from the SPME fibers were investigated using GC–MS, and the resulting chromatograms were analyzed using principal component analysis (PCA) to compare the composition of the pyrolysis vapors over the course of the pyrolysis run. The chemical compositions of both carbohydrate and lignin fragments varied as the char builds up in the reactor bed. Fragments derived from cellulose and hemicelluloses included anhydrosugars, furans, and light-oxygenated compounds. Lignin fragments included methoxyphenols, phenolic ketones, aldehydes, and low-molecular-weight aromatics. The composition of the carbohydrate fragments changed more than those of the lignin fragments as the char built up in the fluid bed. This combination of SPME-GC/MS-PCA was a novel, easy, and effective method for measuring the composition and changes in the composition of pyrolysis vapors during the fast pyrolysis process. This work also highlighted the effect of char build-up on the composition of the overall pyrolysis vapors.

There is a significant need to not only understand how different industries contribute to overall wealth but how they affect certain segments of society. This study augments input-output social account matrix (SAM) modeling techniques with American Community Survey (ACS) Public Use Microdata Samples (PUMS) to better characterize North Carolina forest products industry earnings’ impact on low-, medium-, and high-income households. A 2014 North Carolina SAM was created using IMpact Analysis for PLANning (IMPLAN) and customized so that industry-specific earnings were allocated to household income classes according to the distributions contained within the ACS-PUMS data set. Multipliers were determined to describe earnings distributions per dollar change of final demand. These multipliers were then contextualized by perturbing the SAM model with a 10% change in final demand for relevant forest product industries. The results of the analysis indicate that SAM analysis methods based on unmodified IMPLAN models underestimate earnings paid to low-income and overestimate earnings paid to high-income households resulting from economic growth in the study area. Scenario results obtained using our updated SAM model highlight the improved analytical capabilities of this approach for measuring impacts across income class.

AbstractDeveloping tools and methodologies for the evaluation of sustainable buildings is essential to promote transparency in the building design community. Building sustainability includes attributes from the built, natural, and social systems and inherently requires a series of trade-offs. These complex and often competing priorities require consideration at each stage of a building's life cycle.A total of 24 environmental, social, and economic indicators were developed and applied to three alternative building systems: cross-laminated timber (CLT), steel and glass, and reinforced concrete.The goal of this study was to demonstrate the use of a multi-attribute decision support system (MADSS) that uses a series of indicators, assigns numerical values to these indicators, and then allows for systematic evaluation and ranking of alternatives. A case study approach was used to demonstrate the utility of the MADSS approach in identifying “hot spots” and trade-offs for the three building systems. Portland, Oregon, was selected as the location for the alternative buildings. The functional unit for this study was a mixed-use nine-story building with an area of 19,000 ft2. All processes from extraction of raw materials to end-of-life operations were considered in this study. The CLT building was found to have a higher rank compared with concrete and steel in all three attributes of environmental, economic, and social sustainability.The results of this study are intended to serve as a demonstration of the MADSS tool for building systems and to identify hot spots in the various indicators utilized for sustainability evaluation. The ranking of environmental, social, and economic attributes of building materials on specific indicators will vary with the interests of stakeholders and the building's location, type, design, and other factors.

Overactive Bladder (OAB) is an idiopathic condition, characterized by urgency, urinary frequency, and urgency incontinence, in the absence of routinely traceable urinary infection. We have described microscopic pyuria (≥10 wbc/μl) in patients suffering from the worst symptoms. It is established that inflammation is associated with increased ATP release from epithelial cells, and extracellular ATP originating from the urothelium following increased hydrostatic pressure is a mediator of bladder sensation. Here, using bladder biopsy samples, we have investigated urothelial ATP signaling in OAB patients with microscopic pyuria. Basal, but not stretch-evoked, release of ATP was significantly greater from the urothelium of OAB patients with pyuria than from non-OAB patients or OAB patients without pyuria (<10 wbc/μl). Basal ATP release from the urothelium of OAB patients with pyuria was inhibited by the P2 receptor antagonist suramin and abolished by the hemichannel blocker carbenoxolone, which differed from stretch-activated ATP release. Altered P2 receptor expression was evident in the urothelium from pyuric OAB patients. Furthermore, intracellular bacteria were visualized in shed urothelial cells from ∼80% of OAB patients with pyuria. These data suggest that increased ATP release from the urothelium, involving bacterial colonization, may play a role in the heightened symptoms associated with pyuric OAB patients.

MOMs the word!In a two‐step process, first a trigonal‐prismatic Primary Molecular Building Block ([Cr3O(isonic)6]+, tp‐PMBB‐1) was formed and then it was connected to linear linkers or square‐planar nodes to afford three novel highly charged cationic metal–organic materials (MOMs) with snx, snw, and stptopologies.

In einem zweistufigen Prozesswurden zuerst trigonal‐prismatische molekulare Primärbausteine [Cr3O(isonic)6]+(tp‐PMBB‐1) aufgebaut, die dann durch lineare Brücken oder quadratisch‐planare Knoten zu drei neuartigen, hoch geladenen kationischen Metall‐organischen Materialien (MOMs) mit snx‐, snw‐ und stp‐Topologie verknüpft wurden.

Traditionally, methods to identify community structure in networks have focused on partitioning the vertex set into a number of disjoint groups. However, recently proposed methods have included mechanisms to account for possible overlap between communities. These approaches have taken a wide variety of forms, resulting in a lack of consensus as to what characteristics overlapping communities should have. Additionally, the application of algorithms which account for community overlap are often justified via intuitive rather than empirical arguments. In this text, each of the issues mentioned above is examined. From previous literature, a minimal set of axioms which overlapping communities should satisfy is presented. Additionally, a modification of a previously published algorithm, iterative scan, is introduced to ensure that these properties are met. Finally, the overlap between communities discovered in a large, real world communication network is examined. The analysis offers empirical justification that the application of overlapping community detection methods capture relationships which cannot be identified via traditional disjoint methods.

Background: Protein kinase C (PKC) is a family of isoenzymes that regulate a variety of functions in the central nervous system including neurotransmitter release, ion channel activity, and cell differentiation. Growing evidence suggests that specific isoforms of PKC influence a variety of behavioral, biochemical, and physiological effects of ethanol in mammals. The purpose of this study was to determine whether acute ethanol exposure alters phosphorylation of conventional PKC isoforms at a threonine 674 (p‐cPKC) site in the hydrophobic domain of the kinase, which is required for its catalytic activity.

ABSTRACTPig-tailed macaques (Macaca nemestrina) naturally infected with West Nile virus were monitored from 1999 to 2005 to determine virus-specific antibody seroconversion, prevalence, and persistence. Antibodies persisted for up to 36 months, as detected by epitope-blocking enzyme-linked immunosorbent and hemagglutination inhibition assays. Exposure to cocirculating St. Louis encephalitis virus was evaluated by Western blotting and immunofluorescence assays.

Abstract Fourier transform infrared (FT-IR) microimaging spectroscopy and pyrolysis molecular beam mass spectrometry (py-MBMS) were used as rapid analysis tools to evaluate differences in the chemical composition of 1-year-old transgenic aspens. Multivariate analysis of the spectroscopic data sets was used to compare the cell wall composition of nontransformed control to transgenic aspen plants with GRP-iaaM gene and with GRP-iaaM/35S-ACCase gene. Principal component analysis (PCA) was applied to both the FT-IR and py-MBMS spectra, which revealed sample groupings due to differences in chemical composition. Evaluating the PCA loadings allows determination of the chemical features responsible for the groupings. The FT-IR microimaging data was also used to monitor changes in the chemical composition as a function of the distance from the pith to the bark using partial least squares (PLS) analysis. The analysis shows that the changes in the composition of the xylem that occur over one annual growth ring can be monitored with FT-IR microimaging.

Near infrared (NIR) spectroscopy (500 nm–2400 nm), coupled with multivariate analytic (MVA) statistical techniques, have been used to predict the chemical and mechanical properties of solid loblolly pine wood. The samples were selected from different radial locations and heights of three loblolly pine trees grown in Arkansas. The chemical composition and mechanical properties were measured with traditional wet chemical techniques and three point bending tests, respectively. The microfibril angle was measured with x-ray scattering. These chemical and mechanical properties were correlated with the NIR spectra using projection to latent structures (PLS) models. The correlations were very strong, with the correlation coefficients generally above 0.80. The mechanical properties could also be predicted using a reduced spectral range (650 nm–1150 nm) that should allow for field measurements of these properties using handheld NIR spectrometers.

A series of miscible cellulose ester/poly (vinyl phenol) (CE/PVP) blends containing a latent formaldehyde source were prepared. Due to the low molecular weight of the PVP, the maximum PVP content ID the films was 50 wt %. The blends were then thermally cross-linked ID an attempt to create semi-interpenetrating polymer networks (semi-IPN). The blends were characterized with differential scanning calorimetry, swelling experiments, pyrolysis molecular beam mass spectrometry (py-MBMS), and Fourier transform infrared (FTIR) spectroscopy. The results from the swelling experiments, py-MBMS and FTIR showed that the PVP component did react with the formation of methylene bridges. Blends that contained 50% PVP and high levels of formaldehyde formed semi-IPN structures.

Background: The discriminative stimulus effects of ethanol are mediated in part by the γ‐aminobutyric acid type A (GABAA) receptor system. We have previously shown that microinjections of the competitive GABAAagonist muscimol in the nucleus accumbens and amygdala fully substitute for the discriminative stimulus effects of systemic ethanol. However, it is not known whether allosteric binding sites on GABAAreceptors located within specific limbic brain regions contribute to the discriminative stimulus effects of ethanol.

The performance of phenol-formaldehyde (PF) resins, formulated with lignin derivatives previously synthesized as phenolic resin prepolymers, was evaluated by thermal analysis of the curing process, and by a hard maple shear block test. At 54 and 60% phenol replacement levels, respectively, kraft (KL) and steam explosion lignin (SEL)-based resoles exhibited cure behavior very similar to a standard PF resin. Acid hydrolysis lignin gelled prematurely, and was found to be incompatible with the normal synthesis procedure. Differential scanning calorimetry (DSC) was used to compare kinetic parameters for the curing process of neat and lignin derived phenolic resins. Activation energies and cure rates determined by DSC showed no difference between adhesives. High lignin contents had no inhibitory effect on resin cure. Shear strength properties were evaluated in a compression test, and results illustrate that both lignin-based resins have acceptable strength properties, both in a dry and accelerated aging test. Of the lignins tested, kraft lignin consistently demonstrated superior performance as a pre-polymer in phenolic adhesives. This was attributed to differences in the chemical structure of the two lignins, which had been found to vary in terms of their reactivity with formaldehyde and phenol. KL had been noted to be more amenable to derivatization with formaldehyde and phenol, hence its ability to crosslink with a phenol-formaldehyde fraction during resin synthesis was increased. Positive structural features in KL are a high phenolic guaiacyl (3-methoxy, 4-hydroxy phenyl) content, low carbon-to-carbon bonding between aromatic rings, high solubility in alkali, and a higher number average molecular weight than SEL.

Three series of chain-extended hydroxypropyl lignins (CEEQLs), prepared fran oqanosolv and kraft lignin, were examined regarding their chemical, molecular weight and them1 characteristics. Results showed that the molar substitution (MS) of propylene oxide, which was defined as the number of propoxy repeat units which comprise the chain attached to a single reactive site on lignin, varied and affected copolymer properties. As the MS increased from 1 to 7.2, the number average molecular weight (Mg) increased while the glass transition temperature (Tg) decreased. The actual Mg observed by GPC exceeded however that expected on the basis of mass gain by derivatization. This was attributed to changes in the apparent hydrodynamic volume in relation to MS. The change in Tg with increasing MS followed the Gordon-Taylor relationship. Differences in the chemical composition of the original lignin (organosolv or Kraft) were not obvious as the lignin content of the copolymer decreased below 50%.

Wood fiber-reinforced composites were prepared from poly(hydroxybutyrate) (PHB) and poly(hydroxybutyrate-co-hydroxyvalerate) (PHB/HV) copolymers containing 9 and 24% valerate. The effects of fibers on crystallization were investigated. Thermomechanical pulp, bleached Kraft fibers, and microcrystalline cellulose filler were used as the reinforcing phase. The crystallization of PHB/HV in composite materials was examined using Modulated Differential Scanning Calorimetry (MDSC) and hot-stage microscopy. Hot-stage microscopy showed that polymer crystallites are nucleated on the fiber surface and that the density of nuclei was greater in fiber-reinforced composites than in unfilled material. Dynamic crystallization experiments showed that bleached Kraft, thermomechanical pulp, and microcrystalline cellulose increased the crystallization rate of PHB and PHB/HV both from the glass and melt. However, ultimate crystallinity determined from the heat of crystallization was the same in unreinforced and reinforced materials. The kinetics of PHB/HV crystallization were examined using nonisothermal Avrami-type analysis. Unreinforced and Kraft-reinforced PHB were characterized and compared with unreinforced PHB/9%HV. The Avrami exponent of crystallization, related to nucleation mechanism and growth morphology, is 2.0 for unreinforced PHB, 2.8 for kraft-reinforced PHB, and 3.0 for unreinforced PHB/9%HV. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 64: 1785–1796, 1997

Abstract: The use of membrane processes for the recovery of fermentation products has been gaining increased acceptance in recent years. Pervaporation has been studied in the past as a process for simultaneous fermentation and recovery of volatile products such as ethanol and butanol. However, membrane fouling and low permeate fluxes have imposed limitations on the effectiveness of the process. In this study, we characterize the performance of a substituted polyacetylene membrane, poly[(l-trimethylsilyl)-l-propyne] (PTMSP), in the recovery of ethanol from aqueous mixtures and fermentation broths. Pervaporation using PTMSP membranes shows a distinct advantage over conventional poly(dimethyl siloxane) (PDMS) membranes in ethanol removal. The flux with PTMSP is about threefold higher and the concentration factor is about twofold higher than the corresponding performance achieved with PDMS under similar conditions. The performance of PTMSP with fermentation broths shows a reduction in both flux and concentration factor relative to ethanol-water mixtures. However, the PTMSP membranes indicate initial promise of increased fouling resistance in operation with cell-containing fermentation broths.

The pyran ring proton coupling constants for (+)-catechin have been experimentally determined in deuterated methanol over a temperature range of 213 K to 313 K. The experimental coupling constants were simulated to 0.04 Hz on the average at a 90% confidence limit using a LAOCOON method. The temperature dependence of the coupling constants was reproduced from the Boltzmann distribution of the conformational ensemble generated by the GMMX searching program.

Infant rat hearts from donors weighing approximately 50 g were transplanted to the abdomens of adult mice by primary vascular union. All transplants began to beat within a few minutes after the vascular occluding ties were released, permitting perfusion of the coronary vessels with mouse arterial blood. Rejection of the xenotransplant, as determined by an abrupt decline or cessation of a palpable impulse, occurred between 4 and 5 days in all animals that received no immunosuppression. The administration of mouse antirat serum (eytotoxie titer 1:256) within the first few hours after transplantation resulted in hyperacute rejection of the rat heart as judged by a rapid cessation of the heartbeat. However, as the dilution of heteroantiserum administered to the mouse was progressively increased, a greater percentage of heart grafts in each group did not reject in a hyperacute fashion, and in fact their survival was prolonged. At a dilution of the original heteroantiserum of 1:32, only 2 of 11 rat hearts were hyperacutely rejected, while 9 hearts survived twice as long as grafts in the group that did not receive heteroantiserum. It is suggested that the enhancing ability of heteroantiserum occurs only when its destructive components are in too low a concentration to produce hyperacute rejection.

The development and fielding of the Converter M-228 (SIGCUM) teletypewriter cipher device by the U. S. Army during World War II is described, as is the machine's subsequent failure and removal from service. The cryptologic principles involved in the M-228 axe explained, as well as the method by which the system was solved.

Objectives. We studied the hypothesis that in the absence of vascular pathology, coronary artery vasospasm occurs as a result of local regions of vascular muscle hyperreactivity. We aimed to explore the basis for a functional etiology of those vasospasms not explained on a structural basis.

The viscoelastic properties of mod were investigated using dynamic mechanical thermal analysis and differential scanning calorimetry. Under a limited set of conditions, two separate glass transitions (Tg) could be identified with both techniques. These two transitions were identified as arising from the amorphous lignin and hernicellulose matrix in the wood cell wall. Moisture dramatically affected the temperature at which the two dispersions occurred and, consequently, the ability to resolve their independent responses. The relationship betweenTgand moisture for both components could be modelled with the Kwei equation, which accounts for the presence of secondary interactions. Annealing and specific interactions of a series of organic diluents were wed in an attempt to enhance the resolution of the two components values ofTg. Time-temperature superposition was shown to be applicable to wood plasticized with ethyl formamide, following Williams-Landel-Ferry behaviour over the temperature rangeTgtoTg+ 85° C. These observations allow certain conclusions to be drawn concerning the applicability of existing models of the wood cell wall's supermolecular morphology. Most notably, models of thein situmorphology of the three wood components can be limited to those which consider the amorphous matrix of lignin and hemicellulose to be immiscible.

Blending biomass feedstock is a promising approach to mitigate supply chain risks that are common challenges for large‐scale biomass utilization. Understanding the potential environmental benefits of biofuels produced from blended biomass and identifying driving parameters are critical for the supply chain design. Herein, a cradle‐to‐gate life cycle analysis model for fast pyrolysis biorefineries converting blended feedstocks (pine residues and switchgrass) with traditional centralized and alternative decentralized preprocessing sites, so‐called depots, is explained. Different scenarios are developed to investigate the impacts of parameters such as feedstock blending ratios, biorefinery and depot capacities, preprocessing technologies, and allocation methods. The life‐cycle energy consumption and global warming potential (GWP) of biofuel production with depots vary between 0.7–1.1 MJ MJ−1and 43.2–76.6 g CO2eq. MJ−1, respectively. The results are driven by biorefinery processes and depot preprocesses. A decentralized design reduces the energy consumption of the biorefinery but increases the overall life‐cycle energy and GWP. Such increases can be significantly mitigated by increasing switchgrass content as the energy consumption at the depot is driven largely by the higher moisture content of pine feedstocks. Allocation methods also have a large impact on the results but do not change the major trends and overall conclusions. This study conducts a cradle‐to‐gate life cycle analysis (LCA) on fast pyrolysis biofuel production with decentralized preprocessing sites and blended biomass feedstocks, pine residues and switchgrass. The results are compared with a traditional centralized biorefinery design and the key driving factors are identified.

Rat hearts were transplanted to the abdomens of mice by primary vascular union, and sinus rhythm occurred a few minutes after perfusion of the rat coronary vessels with mouse arterial blood. Five groups of mice with rat heart transplants were studied to evaluate the effect of mouse antirat serum (MARS) and antithymocyte serum (ATS) on the survival of the xenografted hearts. When high-dose MARS was administered, hyperacute rejection occurred, while the administration of low-dose MARS doubled the survival time of the xenotransplant. Antithymocyte serum greatly prolonged the function and survival of the hearts, while the addition of "enhancing serum" to the ATS regimen did not procure longer survival over that achieved by ATS alone.

The article examines several brick designs created by various landscape architectural firms that received the 2006 Brick in Architecture Awards in the U.S. in 2006. The award-winning brick designs were created by Mahan Rykiel Associates Inc. for the Legacy Village in Lyndhurst, Ohio and by Carol R. Johnson Associates for the Beck Cultural Center in Knoxville, Tennessee.

Features playground equipment. Slide/fort and swing set; Wooden galleon, a sandy beach cove, a crocodile made of stones, and totem poles; Use of tires as a playground equipment.

Discusses urban development in Orange County, California. California Coastal Commission's approval of the development of the Dana Point Headlands Conservation Park; Regional parks and conservancies in Orange County; San Francisco Estuary Institute's BayBoards, a project that employs billboards and bus-shelters as signposts for images of the area's forgotten landscape.