Small business finance in two Chicago minority neighborhoods

The authors use survey data to measure the use of formal and informal sources of financing by owners of small businesses in two ethnic neighborhoods. The authors find substantial differences across ethnic groups in the amount of start-up funding obtained and in the use of trade credit.Small business ; Chicago (Ill.)

Use of SWATH mass spectrometry for quantitative proteomic investigation of Shewanella oneidensis MR-1 biofilms grown on graphite cloth electrodes

Quantitative proteomics from low biomass, biofilm samples is not well documented. In this study we show successful use of SWATH-MS for quantitative proteomic analysis of a microbial electrochemically active biofilm. Shewanella oneidensis MR-1 was grown on carbon cloth electrodes under continuous anodic electrochemical polarizations in a bioelectrochemical system (BES). Using lactate as the electron donor, anodes serving as terminal microbial electron acceptors were operated at three different electrode potentials (+0.71 V, +0.21 V & -0.19V vs. SHE) and the development of catalytic activity was monitored by measuring the current traces over time. Once maximum current was reached (usually within 21-29 h) the electrochemical systems were shut off and biofilm proteins were extracted from the electrodes for proteomic assessment. SWATH-MS analysis identified 704 proteins, and quantitative comparison was made of those associated with tricarboxcylic acid (TCA) cycle. Metabolic differences detected between the biofilms suggested a branching of the S. oneidensis TCA cycle when grown at the different electrode potentials. In addition, the higher abundance of enzymes involved in the TCA cycle at higher potential indicates an increase in metabolic activity, which is expected given the assumed higher energy gains. This study demonstrates high numbers of identifications on BES biofilm samples can be achieved in comparison to what is currently reported. This is most likely due to the minimal preparation steps required for SWATH-MS. (C) 2014 Elsevier GmbH. All rights reserved

Antimicrobial effects of free nitrous acid on Desulfovibrio vulgaris: Implications for sulfide-induced corrosion of concrete

Hydrogen sulfide produced by sulfate reducing bacteria (SRB) in sewers causes odor problems and asset deterioration due to the sulfide induced concrete corrosion. Free nitrous acid (FNA) was recently demonstrated as a promising antimicrobial agent to alleviate hydrogen sulfide production in sewers. However, knowledge of the antimicrobial mechanisms of FNA is largely unknown. Here we report the multiple-targeted antimicrobial effects of FNA on the SRB Desulfovibrio vulgaris Hildenborough by determining growth, physiological and gene expression responses to FNA exposure. The activities of growth, respiration and ATP generation were inhibited when exposed to FNA. These changes were reflected in transcript levels detected during exposure. Removal of FNA was evident by nitrite reduction that likely involved nitrite reductase and the poorly characterised hybrid cluster protein, and the genes coding for these proteins were highly expressed. During FNA exposure lowered ribosome activity and protein production were detected. Additionally, conditions within the cells were more oxidising and there was evidence of oxidative stress. Based on interpretation of the measured responses we present a model depicting the antimicrobial effects of FNA on D. vulgaris. These findings provide new insight for understanding the responses of D. vulgaris to FNA and will provide foundation for optimal application of this antimicrobial agent for improved control of sewer corrosion and odor management

Impact of fluctuations in gaseous H2S concentrations on sulfide uptake by sewer concrete: The effect of high H2S loads

The acid production from the oxidation of hydrogen sulfide (H2S) in sewer air results in serious corrosion of exposed concrete surfaces in sewers. Large fluctuations of gaseous H2S concentrations occur in sewers due to the diurnal profiles of sewage flow and retention times and the necessity of intermittent pumping of sewage from pressure pipes into gravity pipes. How the high concentrations of H2S due to these events may affect H2S uptake and subsequent corrosion by concrete sewers is largely unknown. This study determined the effect of short- and long-term increases in H2S levels on the sulfide uptake rate (SUR) of concrete surfaces with an active corrosion layer. The results showed that during the high load situation the SUR increased significantly but then decreased (compared to the baseline SUR) by about 7-14% and 41-50% immediately after short- and long-term H2S high-load periods, respectively. For both exposure conditions, the SUR gradually (over several hours) recovered to approximately 90% of the baseline SUR. Further tests suggest multiple factors may contribute to the observed decrease of SUR directly after the high H2S load. This includes the temporary storage of elemental sulfur in the corrosion layer and inhibition of sulfide oxidizing bacteria (SOB) due to high H2S level and temporary acid surge. Additionally, the delay of the corrosion layer to fully recover the SUR after the high H2S load suggests that there is a longer-term inhibitive effect of the high H2S levels on the activity of the SOB in the corrosion layer. Due to the observed activity reductions, concrete exposed to occasional short-term high H2S load periods had an overall lower H2S uptake compared to concrete exposed to constant H2S levels at the same average concentration. To accurately predict H2S uptake by sewer concrete and hence the likely maximum corrosion rates, a correction factor should be adopted for the H2S fluctuations when average H2S levels are used in the prediction. (C) 2015 Elsevier Ltd. All rights reserved

Identification of controlling factors for the initiation of corrosion of fresh concrete sewers

The development of concrete corrosion in new sewer pipes undergoes an initiation process before reaching an active corrosion stage. This initiation period is assumed to last several months to years but the key factors affecting the process, and its duration, are not well understood. This study is therefore focused on this initial stage of the corrosion process and the effect of key environmental factors. Such knowledge is important for the effective management of corrosion in new sewers, as every year of life extension of such systems has a very high financial benefit. This long-term (4.5 year) study has been conducted in purpose-built corrosion chambers that closely simulated the sewer environment, but with control of three key environmental factors being hydrogen sulfide (H2S) gas phase concentration, relative humidity and air temperature. Fresh concrete coupons, cut from an industry-standard sewer pipe, were exposed to the corrosive conditions in the chambers, both in the gas phase and partially submerged in wastewater. A total of 36 exposure conditions were investigated to determine the controlling factors by regular retrieval of concrete coupons for detailed analysis of surface pH, sulfur compounds (elemental sulfur and sulfate) and concrete mass loss. Corrosion initiation times were thus determined for different exposure conditions. It was found that the corrosion initiation time of both gas-phase and partially-submerged coupons was positively correlated with the gas phase H2S concentration, but only at levels of 10 ppm or below, indicating that sulfide oxidation rate rather than the H2S concentration was the limiting factor during the initiation stage. Relative humidity also played a role for the corrosion initiation of the gas-phase coupons. However, the partially-submerged coupons were not affected by humidity as these coupons were in direct contact with the sewage and hence did have sufficient moisture to enable the microbial processes to proceed. The corrosion initiation time was also shortened by higher gas temperature due to its positive impact on reaction kinetics. These findings provide real opportunities for pro-active sewer asset management with the aim to delay the on-set of the corrosion processes, and hence extend the service life of sewers, through improved prediction and optimization capacity. (C) 2015 Elsevier Ltd. All rights reserved

Evidence of differential adaptation to decreased temperature by anammox bacteria

Low temperature is recognized as one of the major barriers for the application of the anaerobic ammonium oxidation (anammox) process to treat mainstream wastewater. Studies are yet to reveal the underlying biological limitations and molecular mechanisms associated with the inhibition of low temperature on the anammox process. In this study, metaproteomics was used to examine proteome modulation patterns of the anammox community occurring at different temperatures. The anammox community remarkably altered their proteomes when the temperature decreased from 35 to 20°C. This was especially for proteins involved in energy conversion, transcription and translation, and inorganic ion transport. However, at 15 C the anammox activities became distinctly inhibited, and there was evidence of energy limitations and severe stress in Candidatus Kuenenia and to a lesser degree in Candidatus Brocadia. Candidatus Jettenia exhibited more changes in its proteome at 15°C. From the proteomes, at the lower temperatures there was evidence of stress caused by toxic nitrogen compounds or reactive oxygen species in the anammox bacteria. Hydroxylamine oxidoreductase (HAO)-like proteins and an oxidative stress response protein (a catalase) were in high abundance to potentially ameliorate these inhibitory effects. This study offers metaproteomic insight into the anammox community-based physiological response to decreasing temperatures. This article is protected by copyright. All rights reserved

Noise Properties of the BOOMERANG Instrument

In this paper we report a short description of the BOOMERANG experiment explaining his scientific goal and the technologies implied. We concentrate then on the analysis of the noise properties discussing in particular the scan synchronous noise. Finally we present the calibration technique and the sensitivity of all the channels

Human umbilical cord perivascular cells improve human pancreatic islet transplant function by increasing vascularization

Islet transplantation is an efficacious therapy for type 1 diabetes; however, islets from multiple donor pancreata are required, and a gradual attrition in transplant function is seen. Here, we manufactured human umbilical cord perivascular mesenchymal stromal cells (HUCPVCs) to Good Manufacturing Practice (GMP) standards. HUCPVCs showed a stable phenotype while undergoing rapid ex vivo expansion at passage 2 (p2) to passage 4 (p4) and produced proregenerative factors, strongly suppressing T cell responses in the resting state and in response to inflammation. Transplanting an islet equivalent (IEQ):HUCPVC ratio of 1:30 under the kidney capsule in diabetic NSG mice demonstrated the fastest return to normoglycemia by 3 days after transplant: Superior glycemic control was seen at both early (2.7 weeks) and later stages (7, 12, and 16 weeks) versus ratios of 1:0, 1:10, and 1:50, respectively. Syngeneic islet transplantation in immunocompetent mice using the clinically relevant hepatic portal route with a marginal islet mass showed that mice transplanted with an IEQ:HUCPVC ratio of 1:150 had superior glycemic control versus ratios of 1:0, 1:90, and 1:210 up to 6 weeks after transplant. Immunodeficient mice transplanted with human islets (IEQ:HUCPVC ratio of 1:150) exhibited better glycemic control for 7 weeks after transplant versus islet transplant alone, and islets transplanted via the hepatic portal vein in an allogeneic mouse model using a curative islet mass demonstrated delayed rejection of islets when cotransplanted with HUCPVCs (IEQ:HUCPVC ratio of 1:150). The immunosuppressive and proregenerative properties of HUCPVCs demonstrated long-term positive effects on graft function in vivo, indicating that they may improve long-term human islet allotransplantation outcomes

Free sulfurous acid (FSA) inhibition of biological thiosulfate reduction (BTR) in the sulfur cycle-driven wastewater treatment process

A sulfur cycle-based bioprocess for co-treatment of wet flue gas desulfurization (WFGD) wastes with freshwater sewage has been developed. In this process the removal of organic carbon is mainly associated with biological sulfate or sulfite reduction. Thiosulfate is a major intermediate during biological sulfate/sulfite reduction, and its reduction to sulfide is the rate-limiting step. In this study, the impacts of saline sulfite (the ionized form: HSO + SO ) and free sulfurous acid (FSA, the unionized form: HSO) sourced from WGFD wastes on the biological thiosulfate reduction (BTR) activities were thoroughly investigated. The BTR activity and sulfate/sulfite-reducing bacteria (SRB) populations in the thiosulfate-reducing up-flow anaerobic sludge bed (UASB) reactor decreased when the FSA was added to the UASB influent. Batch experiment results confirmed that FSA, instead of saline sulfite, was the true inhibitor of BTR. And BTR activities dropped by 50% as the FSA concentrations were increased from 8.0 × 10to 2.0 × 10mg HSO-S/L. From an engineering perspective, the findings of this study provide some hints on how to ensure effective thiosulfate accumulation in biological sulfate/sulfite reduction for the subsequent denitrification/denitritation. Such manipulation would result in higher nitrogen removal rates in this co-treatment process of WFGD wastes with municipal sewage

LSST: from Science Drivers to Reference Design and Anticipated Data Products

(Abridged) We describe here the most ambitious survey currently planned in the optical, the Large Synoptic Survey Telescope (LSST). A vast array of science will be enabled by a single wide-deep-fast sky survey, and LSST will have unique survey capability in the faint time domain. The LSST design is driven by four main science themes: probing dark energy and dark matter, taking an inventory of the Solar System, exploring the transient optical sky, and mapping the Milky Way. LSST will be a wide-field ground-based system sited at Cerro Pach\'{o}n in northern Chile. The telescope will have an 8.4 m (6.5 m effective) primary mirror, a 9.6 deg$^2$ field of view, and a 3.2 Gigapixel camera. The standard observing sequence will consist of pairs of 15-second exposures in a given field, with two such visits in each pointing in a given night. With these repeats, the LSST system is capable of imaging about 10,000 square degrees of sky in a single filter in three nights. The typical 5$\sigma$ point-source depth in a single visit in $r$ will be $\sim 24.5$ (AB). The project is in the construction phase and will begin regular survey operations by 2022. The survey area will be contained within 30,000 deg$^2$ with $\delta<+34.5^\circ$, and will be imaged multiple times in six bands, $ugrizy$, covering the wavelength range 320--1050 nm. About 90\% of the observing time will be devoted to a deep-wide-fast survey mode which will uniformly observe a 18,000 deg$^2$ region about 800 times (summed over all six bands) during the anticipated 10 years of operations, and yield a coadded map to $r\sim27.5$. The remaining 10\% of the observing time will be allocated to projects such as a Very Deep and Fast time domain survey. The goal is to make LSST data products, including a relational database of about 32 trillion observations of 40 billion objects, available to the public and scientists around the world.Comment: 57 pages, 32 color figures, version with high-resolution figures available from https://www.lsst.org/overvie