bluuebunny/crossref_metadata_2025_split huggingface dataset:
Generalized Regeneration Theory and its Energy Saving and Emission Reduction Effects on Coal-Fired Power Generation
Authors: Feng Weizhong 
Published: November 2016

Concerns related to global warming and environmental pollution concerns have pressured coal-fired power plants to improve efficiency and reduce emissions. However, the conventional efficiency improvement methods — increasing steam pressure and temperature and reducing condenser pressure are limited by material technology and the temperature of the available cooling medium. The next step for increasing efficiency would be to add additional reheat or regenerative cycles, but this is not feasible for existing plants.
In addition, as the share of renewable energy and the grid’s demands on the coal-fired power plants increases, China’s coal-fired units are faced with more and tougher challenges, including large peak-valley gaps, frequent startups and shutdowns and cost pressures. As a result, the boiler combustion efficiency decreases and incidents such as furnace explosions, aggravation and collapsing of slag and burning of facilities located downstream of the economizer become more frequent.
To address these problems, the generalized regeneration theory has been proposed and a series of related technologies have been developed, providing a new approach for not only improving the efficiency of coal-fired power plants, but also resulted in boiler operation that is cleaner and safer. These technologies which include anew boiler startup technology, the high efficiency combustion and low emission technology under low load and the low oxygen, and a low NOx and high efficiency combustion technology under high load have been implemented successfully in the Shanghai Waigaoqiao No. 3 power plant.
By improving the utilization of turbine extraction and reducing the exhaust loss, these innovative technologies greatly improve the environmental performance, efficiency and safety of the units in various operating conditions. In addition, improvements have been made in the boilers ability to adapt to changing coal supplies, particularly for coal with high slagging tendencies and high moisture content.
Wet Partial Oxidation of JP8 in a Well-Insulated Reactor
Authors: Scenna Richard , Gupta Ashwani K. 
Published: November 2016

This work investigates wet and dry non-catalytic partial oxidation of JP8 under distributed reaction regime condition. Previous works have demonstrated the potential of the distributed reaction regime to increase hydrogen and carbon monoxide production over conventional non-catalytic reforming and suppress soot formation inside the reactor. Jet propellant 8 (JP8) has a high sulfur content (up to 3000ppm) and a tendency to form coke, making it an ideal candidate for this non-catalytic approach. Experimental results are reported with the reactor operated at fixed oxygen to carbon ratio of 1.08 and steam to carbon ratios varied from 0.0 to 0.23. Numerical simulations were used to determine flame regime and extent of distribution.
Steam provided favorable effects even with trace amounts (S/C=0.01), but more pronounced effects were observed at steam to carbon ratio of 0.17. Syngas composed of 22.5–24.6% hydrogen and 20.1–23.3% carbon monoxide was evolved. Of the hydrocarbons detected, only methane was seen in finite amounts (0.17–0.29%). The increase in performance in terms of reforming efficiency and conversion exceeded what can be ascribed to steam reforming reactions alone. Additional enhancement is attributed to distributed reaction in the reactor. Reforming efficiency of approximately 68–80% is comparable to that from catalytic reforming. Low steam to carbon ratio offers higher sustainability in mobile power systems at reduced costs from direct use of water recovered from fuel cells.
Measurements of Hydrogen Enriched Combustion of Jet Fuel in Open Flame
Authors: Seibert Michael , Nieh Sen 
Published: November 2016

Jet fuel is a common logistics fuel, even for small, mobile systems. At low power output (<2 kWe), technologies such as Stirling engines, thermo electric and thermo-photovoltaic generators have the potential to compete with diesel engines, but require reliable jet fuel combustion. Hydrogen enrichment is presented as a control parameter to improve jet fuel combustion.
Research in fuel reforming gives an opportunity for hydrogen production at the point of use. Hydrogen enriched combustion of jet fuel seeks to take advantage of the energy density of jet fuel and the combustibility of hydrogen.
Experiments were conducted with atomized jet fuel in a 5 kWth open flame. Jet fuel is sprayed through an air atomizing nozzle. Hydrogen was added to either the atomizing air or to a concentric tube supplying the main combustion air. During hydrogen enrichment, jet fuel flow rate was reduced to maintain constant fuel energy input. Temperature is measured vertically and laterally through the flame. Gaseous emissions are measured above the visible flame.
In these experiments, hydrogen represented up to 26% of the fuel energy contribution. Substantial changes to the combustion profile occur with small amounts of hydrogen enrichment. The advantages it provides represent opportunities for reduced size, improved operational reliability and control and reduced pollutant emissions.
Revisiting Parabolic Trough Concentrators for Industrial Process Heat in the United States
Authors: Turchi Craig S. , Kurup Parthiv , Zhu Guangdong 
Published: November 2016

After significant interest in the 1970s, but relatively few deployments, the use of concentrating solar collectors for thermal applications, including enhanced oil recovery, desalination, and industrial process heat (IPH), is again increasing in global interest. In particular, recent advances in collector design and manufacturing have led to reduced cost per square meter of aperture area. In this study, analysis of a modern parabolic trough that is suited for use in small solar IPH (SIPH) applications predicts that the installed solar field cost can be as low as $170/m2. A slightly higher cost of $200/m2 is estimated for facilities typical of a SIPH plant size. Full project costs will include additional costs for contingency, piping and heat exchanger interface, and project indirect costs.
The cost for solar-generated heat by SIPH is quantified by defining the levelized cost of heat (LCOH). California offers a favorable environment for SIPH given its good insolation, gas prices typically higher than the national average, and policies promoting solar-thermal deployment. Given historically low gas prices, competing with natural gas remains the primary challenge to deployment. However, this study finds that the solar LCOH for many regions in California is lower than the LCOH from natural gas, using a representative installed solar hardware price and the average price for industrial natural gas in California.
Lastly, modification are in progress to the parabolic trough model within NREL’s System Advisor Model (SAM) to allow users to more easily predict performance for these steam-generation applications.
Selection of Resistance to Clarithromycin in Mycobacterium abscessus Subspecies
Authors: Mougari Faiza , Bouziane Feriel , Crockett Flora , Nessar Rachid , Chau Françoise , Veziris Nicolas , Sapriel Guillaume , Raskine Laurent , Cambau Emmanuelle 
Published: November 2016

ABSTRACT

Mycobacterium abscessus
is an emerging pathogen against which clarithromycin is the main drug used. Clinical failures are commonly observed and were first attributed to acquired mutations in
rrl
encoding 23S rRNA but were then attributed to the intrinsic production of the
erm
(41) 23S RNA methylase. Since strains of
M. abscessus
were recently distributed into subspecies and
erm
(41) sequevars, we investigated acquired clarithromycin resistance mechanisms in mutants selected
in vitro
from four representative strains. Mutants were sequenced for
rrl
,
erm
(41),
whiB
,
rpIV
, and
rplD
and studied for seven antibiotic MICs. For mutants obtained from strain
M. abscessus
subsp.
abscessus
erm
(41) T28 sequevar and strain
M. abscessus
subsp.
bolletii
, which are both known to produce effective methylase,
rrl
was mutated in only 19% (4/21) and 32.5% (13/40) of mutants, respectively, at position 2058 (A2058C, A2058G) or position 2059 (A2059C, A2059G). No mutations were observed in any of the other genes studied, and resistance to other antibiotics (amikacin, cefoxitin, imipenem, tigecycline, linezolid, and ciprofloxacin) was mainly unchanged. For
M. abscessus
subsp.
abscessus
erm
(41) C28 sequevar and
M. abscessus
subsp.
massiliense
, not producing effective methylase, 100% (26/26) and 97.5% (39/40) of mutants had
rrl
mutations at position 2058 (A2058C, A2058G, A2058T) or position 2059 (A2059C, A2059G). The remaining
M. abscessus
subsp.
massiliense
mutant showed an 18-bp repeat insertion in
rpIV
, encoding the L22 protein. Our results showed that acquisition of clarithromycin resistance is 100% mediated by structural 50S ribosomal subunit mutations for
M. abscessus
subsp.
abscessus
erm
(41) C28 and
M. abscessus
subsp.
massiliense
, whereas it is less common for
M. abscessus
subsp.
abscessus
erm
(41) T28 sequevar and
M. abscessus
subsp.
bolletii
, where other mechanisms may be responsible for failure.
Mechanisms of Increased Resistance to Chlorhexidine and Cross-Resistance to Colistin following Exposure of Klebsiella pneumoniae Clinical Isolates to Chlorhexidine
Authors: Wand Matthew E. , Bock Lucy J. , Bonney Laura C. , Sutton J. Mark 
Published: November 2016

ABSTRACT

Klebsiella pneumoniae
is an opportunistic pathogen that is often difficult to treat due to its multidrug resistance (MDR). We have previously shown that
K. pneumoniae
strains are able to “adapt” (become more resistant) to the widely used bisbiguanide antiseptic chlorhexidine. Here, we investigated the mechanisms responsible for and the phenotypic consequences of chlorhexidine adaptation, with particular reference to antibiotic cross-resistance. In five of six strains, adaptation to chlorhexidine also led to resistance to the last-resort antibiotic colistin. Here, we show that chlorhexidine adaptation is associated with mutations in the two-component regulator
phoPQ
and a putative Tet repressor gene (
smvR
) adjacent to the major facilitator superfamily (MFS) efflux pump gene,
smvA
. Upregulation of
smvA
(10- to 27-fold) was confirmed in
smvR
mutant strains, and this effect and the associated phenotype were suppressed when a wild-type copy of
smvR
was introduced on plasmid pACYC. Upregulation of
phoPQ
(5- to 15-fold) and
phoPQ
-regulated genes,
pmrD
(6- to 19-fold) and
pmrK
(18- to 64-fold), was confirmed in
phoPQ
mutant strains. In contrast, adaptation of
K. pneumoniae
to colistin did not result in increased chlorhexidine resistance despite the presence of mutations in
phoQ
and elevated
phoPQ
,
pmrD
, and
pmrK
transcript levels. Insertion of a plasmid containing
phoPQ
from chlorhexidine-adapted strains into wild-type
K. pneumoniae
resulted in elevated expression levels of
phoPQ
,
pmrD
, and
pmrK
and increased resistance to colistin, but not chlorhexidine. The potential risk of colistin resistance emerging in
K. pneumoniae
as a consequence of exposure to chlorhexidine has important clinical implications for infection prevention procedures.
In Vitro
-
In Vivo
Discordance with Humanized Piperacillin-Tazobactam Exposures against Piperacillin-Tazobactam-Resistant/Pan-β-Lactam-Susceptible Escherichia coli
Authors: Monogue M. L. , Nicolau D. P. 
Published: November 2016

ABSTRACT

Recent findings have identified
Escherichia coli
strains that are pan-β-lactam susceptible (PBL-S) but piperacillin-tazobactam resistant (TZP-R)
in vitro
. We assessed the
in vivo
significance of this resistance profile in a neutropenic murine pneumonia model using humanized exposures of TZP with 18 clinical
E. coli
isolates, 8 TZP-S/PBL-S and 10 genotypically confirmed TZP-R/PBL-S. Despite phenotypically and genotypically defined resistance, TZP displayed efficacy against these isolates. Additional studies are required to define the clinical implications of these TZP-R/PBL-S strains.
Caged Garcinia Xanthones, a Novel Chemical Scaffold with Potent Antimalarial Activity
Authors: Ke Hangjun , Morrisey Joanne M. , Qu Shiwei , Chantarasriwong Oraphin , Mather Michael W. , Theodorakis Emmanuel A. , Vaidya Akhil B. 
Published: November 2016

ABSTRACTCagedGarciniaxanthones (CGXs) constitute a family of natural products that are produced by tropical/subtropical trees of the genusGarcinia. CGXs have a unique chemical architecture, defined by the presence of a caged scaffold at the C ring of a xanthone moiety, and exhibit a broad range of biological activities. Here we show that synthetic CGXs exhibit antimalarial activity againstPlasmodium falciparum, the causative parasite of human malaria, at the intraerythrocytic stages. Their activity can be substantially improved by attaching a triphenylphosphonium group at the A ring of the caged xanthone. Specifically, CR135 and CR142 were found to be highly effective antimalarial inhibitors, with 50% effective concentrations as low as ∼10 nM. CGXs affect malaria parasites at multiple intraerythrocytic stages, with mature stages (trophozoites and schizonts) being more vulnerable than immature rings. Within hours of CGX treatment, malaria parasites display distinct morphological changes, significant reduction of parasitemia (the percentage of infected red blood cells), and aberrant mitochondrial fragmentation. CGXs do not, however, target the mitochondrial electron transport chain, the target of the drug atovaquone and several preclinical candidates. CGXs are cytotoxic to human HEK293 cells at the low micromolar level, which results in a therapeutic window of around 150-fold for the lead compounds. In summary, we show that CGXs are potent antimalarial compounds with structures distinct from those of previously reported antimalarial inhibitors. Our results highlight the potential to further developGarcinianatural product derivatives as novel antimalarial agents.
Evaluation of MIC Strip Isavuconazole Test for Susceptibility Testing of Wild-Type and Non-Wild-Type Aspergillus fumigatus Isolates
Authors: Arendrup Maiken Cavling , Verweij Paul , Nielsen Henrik Vedel 
Published: November 2016

ABSTRACT

We evaluated the MIC Strip Isavuconazole test against EUCAST E.Def 9.3 by using 40 wild-type and 39
CYP51A
mutant
Aspergillus fumigatus
strains. The strip full inhibition endpoint (FIE) and 80% growth inhibition endpoint were determined by two independent readers, reader 1 (R1) and R2. The essential (within ±0, ±1, and ±2 twofold dilutions) and categorical agreements were best with the FIE (for R1/R2, 42%/41%, 75%/73%, and 90%/89% for essential agreement, and 91.1%/92.4% categorical agreement, with 6.3/8.9% very major errors and 0/1.3% major errors, respectively). The MIC Strip Isavuconazole test with the FIE appears to be useful.
Population Pharmacokinetic Modeling To Estimate the Contributions of Genetic and Nongenetic Factors to Efavirenz Disposition
Authors: Robarge Jason D. , Metzger Ingrid F. , Lu Jessica , Thong Nancy , Skaar Todd C. , Desta Zeruesenay , Bies Robert R. 
Published: November 2016

ABSTRACTEfavirenz pharmacokinetics is characterized by large between-subject variability, which determines both therapeutic response and adverse effects. Some of the variability in efavirenz pharmacokinetics has been attributed to genetic variability in cytochrome P450 genes that alter efavirenz metabolism, such asCYP2B6andCYP2A6. While the effects of additional patient factors have been studied, such as sex, weight, and body mass index, the extent to which they contribute to variability in efavirenz exposure is inconsistently reported. The aim of this analysis was to develop a pharmacometric model to quantify the contribution of genetic and nongenetic factors to efavirenz pharmacokinetics. A population-based pharmacokinetic model was developed using 1,132 plasma efavirenz concentrations obtained from 73 HIV-seronegative volunteers administered a single oral dose of 600 mg efavirenz. A two-compartment structural model with absorption occurring by zero- and first-order processes described the data. Allometric scaling adequately described the relationship between fat-free mass and apparent oral clearance, as well as fat mass and apparent peripheral volume of distribution. Inclusion of fat-free mass and fat mass in the model mechanistically accounted for correlation between these disposition parameters and sex, weight, and body mass index. Apparent oral clearance of efavirenz was reduced by 25% and 51% in subjects predicted to have intermediate and slow CYP2B6 metabolizer status, respectively. The final pharmacokinetic model accounting for fat-free mass, fat mass, and CYP2B6 metabolizer status was consistent with known mechanisms of efavirenz disposition, efavirenz physiochemical properties, and pharmacokinetic theory. (This study has been registered at ClinicalTrials.gov under identifier NCT00668395.)
MicroRNAs Modulate Pathogenesis Resulting from Chlamydial Infection in Mice
Authors: Yeruva Laxmi , Pouncey Dakota L. , Eledge Michael R. , Bhattacharya Sudeepa , Luo Chunqiao , Weatherford Erin W. , Ojcius David M. , Rank Roger G. 
Published: November 2016

ABSTRACT

Not all women infected with chlamydiae develop upper genital tract disease, but the reason(s) for this remains undefined. Host genetics and hormonal changes associated with the menstrual cycle are possible explanations for variable infection outcomes. It is also possible that disease severity depends on the virulence of the chlamydial inoculum. It is likely that the inoculum contains multiple genetic variants, differing in virulence. If the virulent variants dominate, then the individual is more likely to develop severe disease. Based on our previous studies, we hypothesized that the relative degree of virulence of a chlamydial population dictates the microRNA (miRNA) expression profile of the host, which, in turn, through regulation of the host inflammatory response, determines disease severity. Thus, we infected C57BL/6 mice with two populations of
Chlamydia muridarum
, each comprised of multiple genetic variants and differing in virulence: an attenuated strain (Nigg
A
) and a virulent strain (Nigg
V
). Nigg
A
and Nigg
V
elicited upper tract pathology in 54% and 91% of mice, respectively. miRNA expression analysis in Nigg
V
-infected mice showed significant downregulation of miRNAs involved in dampening fibrosis (miR-200b, miR-200b-5p, and 200b-3p miR-200a-3p) and in transcriptional regulation of cytokine responses (miR-148a-3p, miR-152-3p, miR-132, and miR-212) and upregulation of profibrotic miRNAs (miR-142, and miR-147). Downregulated miRNAs were associated with increased expression of interleukin 8 (IL-8), CXCL2, IL-1β, tumor necrosis factor alpha (TNF-α), and IL-6. Infection with Nigg
V
but not Nigg
A
led to decreased expression of Dicer and Ago 2, suggesting that Nigg
V
interaction with host cells inhibits expression of the miRNA biogenesis machinery, leading to increased cytokine expression and pathology.
Specific Human and Candida Cellular Interactions Lead to Controlled or Persistent Infection Outcomes during Granuloma-Like Formation
Authors: Misme-Aucouturier Barbara , Albassier Marjorie , Alvarez-Rueda Nidia , Le Pape Patrice 
Published: November 2016

ABSTRACTA delayed type of multicellular process could be crucial during chronic candidiasis in determining the course of infection. This reaction, consisting of organized immune cells surrounding the pathogen, initiates an inflammatory response to avoid fungal dissemination. The goal of the present study was to examine, at anin vitrocellular scale,Candidaand human immune cell interaction dynamics during a long-term period. By challenging human peripheral blood immune cells from 10 healthy donors with 32Candida albicansand non-albicans(C. glabrata,C. tropicalis,C. parapsilosis,C. dubliniensis,C. lusitaniae,C. krusei, andC. kefyr) clinical isolates, we showed thatCandidaspp. induced the formation of granuloma-like structures within 6 days after challenge, but their sizes and the respective fungal burdens differed according to theCandidaspecies. These two parameters are positively correlated. Phenotypic characteristics, such as hypha formation and higher axenic growth rate, seem to contribute to yeast persistence within granuloma-like structures. We showed an interindividual variability of the human response againstCandidaspp. Higher proportions of neutrophils and elevated CD4+/CD8+T cell ratios during the first days after challenge were correlated with early production of gamma interferon (IFN-γ) and associated with controlled infection. In contrast, the persistence ofCandidacould result from upregulation of proinflammatory cytokines such as interleukin-6 (IL-6), IFN-γ, and tumor necrosis factor alpha (TNF-α) and a poor anti-inflammatory negative feedback (IL-10). Importantly, regulatory subsets of NK cells and CD4loCD8hidoubly positive (DP) lymphocytes at late stage infiltrate granuloma-like structures and could correlate with the IL-10 and TNF-α production. These data offer a base frame to explain cellular events that guide infection control or fungal persistence.
Functional Impairment of Murine Dendritic Cell Subsets following Infection with Infective Larval Stage 3 of Brugia malayi
Authors: Sharma Aditi , Sharma Pankaj , Vishwakarma Achchhe Lal , Srivastava Mrigank 
Published: November 2016

ABSTRACT

Filarial parasites cause functional impairment of host dendritic cells (DCs). However, the effects of early infection on individual DC subsets are not known. In this study, we infected BALB/c mice with infective stage 3 larvae of the lymphatic filarial parasite
Brugia malayi
(Bm-L3) and studied the effect on fluorescence-activated cell sorter (FACS)-sorted DC subsets. While myeloid DCs (mDCs) accumulated by day 3 postinfection (p.i.), lymphoid DCs (LDCs) and CD8
+
plasmacytoid DCs (pDCs) peaked at day 7 p.i. in the spleens and mesenteric lymph nodes (mLNs) of infected mice. Increased tumor necrosis factor alpha (TNF-α) but reduced interleukin 12 (IL-12) and Toll-like receptor 4 (TLR4), -6, and -9 and reciprocal secretion of IL-4 and IL-10 were also observed across all DC subsets. Interestingly, Bm-L3 increased the expression of CD80 and CD86 across all DC subsets but decreased that of major histocompatibility complex class II (MHC-II) on mDCs and pDCs, resulting in their impaired antigen uptake and presentation capacities, but maximally attenuated the T-cell proliferation capacity of only mDCs. Furthermore, Bm-L3 increased phosphorylated p38 (p-p38), but not p-ERK, in mDCs and LDCs but downregulated them in pDCs, along with differential modulation of protein tyrosine phosphatases SHP-1, TCPTP, PTEN, and PTP1B across all DC subsets. Taken together, we report hitherto undocumented effects of early Bm-L3 infection on purified host DC subsets that lead to their functional impairment and attenuated host T-cell response.