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1.
Philos Trans A Math Phys Eng Sci ; 375(2100)2017 Aug 13.
Article in English | MEDLINE | ID: mdl-29052549

ABSTRACT

We present a methodology for assessing the economic impact of power storage technologies. The methodology is founded on classical approaches to the optimal stopping of stochastic processes but involves an innovation that circumvents the need to, ex ante, identify the form of a driving process and works directly on observed data, avoiding model risks. Power storage is regarded as a complement to the intermittent output of renewable energy generators and is therefore important in contributing to the reduction of carbon-intensive power generation. Our aim is to present a methodology suitable for use by policy makers that is simple to maintain, adaptable to different technologies and easy to interpret. The methodology has benefits over current techniques and is able to value, by identifying a viable optimal operational strategy, a conceived storage facility based on compressed air technology operating in the UK.This article is part of the themed issue 'Energy management: flexibility, risk and optimization'.

2.
Pest Manag Sci ; 73(10): 2138-2148, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28432725

ABSTRACT

BACKGROUND: An insecticide screening effort identified N-(4-bromophenyl)-4,6-bis(2,2,2-trifluoroethoxy)-1,3,5-triazine-2-amine as having weak potency against two lepidopteran species, Helicoverpa zea and Spodoptera exigua. A structure-activity relationship study about the trifluoroethoxy substituents and the aniline of this compound was carried out in an effort to improve insecticidal potency. RESULTS: Initially, a series of analogs bearing various substituents on the aniline were prepared, and the insecticidal potency was evaluated against H. zea and S. exigua in greenhouse diet feeding assays. The results showed that electron-withdrawing substituents, such as Cl, Br and CF3 , were preferred over electron-donating substituents, such as methoxy, and that potency was significantly better when the substituent was in the para-position. Additional investigations showed that bis(anilino)trifluoroethoxytriazines were more potent. Replacement of the remaining trifluoroethyl group in the bis(anilino)triazine series with an alkyl amine lead to compounds of equal or superior efficacy. CONCLUSION: The work presented showed that electron-withdrawing substituents in the para-position of the aniline ring of the initial hit delivered the best levels of insecticidal potency against the two insect species tested. Further investigations showed that potency could be improved by replacing one of the two trifluoroethoxy groups with additional 4-substituted aniline. This level of potency was maintained or further improved when the remaining trifluoroethoxy was replaced with a substituted amine. © 2017 Society of Chemical Industry.


Subject(s)
Amines/pharmacology , Insecticides/pharmacology , Moths/drug effects , Triazines/pharmacology , Animals , Larva/drug effects , Larva/growth & development , Moths/growth & development , Spodoptera/drug effects , Spodoptera/growth & development , Structure-Activity Relationship
3.
Bioorg Med Chem ; 24(3): 378-82, 2016 Feb 01.
Article in English | MEDLINE | ID: mdl-26706115

ABSTRACT

Sap-feeding insect pests constitute a major insect pest complex that includes a range of aphids, whiteflies, planthoppers and other insect species. Sulfoxaflor (Isoclast™ active), a new sulfoximine class insecticide, targets sap-feeding insect pests including those resistant to many other classes of insecticides. A structure activity relationship (SAR) investigation of the sulfoximine insecticides revealed the importance of a 3-pyridyl ring and a methyl substituent on the methylene bridge linking the pyridine and the sulfoximine moiety to achieving strong Myzus persicae activity. A more in depth QSAR investigation of pyridine ring substituents revealed a strong correlation with the calculated logoctanol/water partition coefficient (SlogP). Model development resulted in a highly predictive model for a set of 18 sulfoximines including sulfoxaflor. The model is consistent with and helps explain the highly optimized pyridine substitution pattern for sulfoxaflor.


Subject(s)
Aphids/drug effects , Insecticides/chemistry , Insecticides/pharmacology , Pyridines/chemistry , Pyridines/pharmacology , Sulfur Compounds/chemistry , Sulfur Compounds/pharmacology , Animals , Dose-Response Relationship, Drug , Molecular Structure , Structure-Activity Relationship
4.
J Bus Ethics ; 131(1): 43-67, 2015.
Article in English | MEDLINE | ID: mdl-26430288

ABSTRACT

This paper argues that the subsistence of the fundamental theorem of contemporary financial mathematics is the ethical concept 'reciprocity'. The argument is based on identifying an equivalence between the contemporary, and ostensibly 'value neutral', Fundamental Theory of Asset Pricing with theories of mathematical probability that emerged in the seventeenth century in the context of the ethical assessment of commercial contracts in a framework of Aristotelian ethics. This observation, the main claim of the paper, is justified on the basis of results from the Ultimatum Game and is analysed within a framework of Pragmatic philosophy. The analysis leads to the explanatory hypothesis that markets are centres of communicative action with reciprocity as a rule of discourse. The purpose of the paper is to reorientate financial economics to emphasise the objectives of cooperation and social cohesion and to this end, we offer specific policy advice.

5.
Ground Water ; 53(6): 920-32, 2015.
Article in English | MEDLINE | ID: mdl-25457440

ABSTRACT

Biostimulation is increasingly used to accelerate microbial remediation of recalcitrant groundwater contaminants. Effective application of biostimulation requires successful emplacement of amendment in the contaminant target zone. Verification of remediation performance requires postemplacement assessment and contaminant monitoring. Sampling-based approaches are expensive and provide low-density spatial and temporal information. Time-lapse electrical resistivity tomography (ERT) is an effective geophysical method for determining temporal changes in subsurface electrical conductivity. Because remedial amendments and biostimulation-related biogeochemical processes often change subsurface electrical conductivity, ERT can complement and enhance sampling-based approaches for assessing emplacement and monitoring biostimulation-based remediation. Field studies demonstrating the ability of time-lapse ERT to monitor amendment emplacement and behavior were performed during a biostimulation remediation effort conducted at the Department of Defense Reutilization and Marketing Office (DRMO) Yard, in Brandywine, Maryland, United States. Geochemical fluid sampling was used to calibrate a petrophysical relation in order to predict groundwater indicators of amendment distribution. The petrophysical relations were field validated by comparing predictions to sequestered fluid sample results, thus demonstrating the potential of electrical geophysics for quantitative assessment of amendment-related geochemical properties. Crosshole radar zero-offset profile and borehole geophysical logging were also performed to augment the data set and validate interpretation. In addition to delineating amendment transport in the first 10 months after emplacement, the time-lapse ERT results show later changes in bulk electrical properties interpreted as mineral precipitation. Results support the use of more cost-effective surface-based ERT in conjunction with limited field sampling to improve spatial and temporal monitoring of amendment emplacement and remediation performance.


Subject(s)
Electric Conductivity , Environmental Monitoring/methods , Environmental Restoration and Remediation , Groundwater/chemistry , Maryland , Water Pollutants, Chemical/analysis
6.
Pest Manag Sci ; 71(7): 928-36, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25067823

ABSTRACT

BACKGROUND: Sulfoxaflor, a new insect control agent developed by Dow AgroSciences, exhibits broad-spectrum control of many sap-feeding insect pests, including aphids, whiteflies, leafhoppers, planthoppers and lygus bugs. During the development of sulfoxaflor, structure-activity relationship (SAR) exploration of the sulfoximine functional group revealed that the nature of the sulfoximine nitrogen substituent significantly affects insecticidal acitivity. As part of the investigation to probe the various electronic, steric and lipophilic parameters at this position, a series of N-heterocyclic sulfoximines were synthesized and tested for bioactivity against green peach aphid. RESULTS: Using a variety of chemistries, the nitrile substituent was replaced with different substituted five- and six-membered heterocycles. The compounds in the series were then tested for insecticidal acitivty against green peach aphid in foliar spray assays. In spite of the larger steric demand of these substituents, the resulting N-heterocyclic sulfoximine analogs displayed good levels of efficacy. In particular, the N-thiazolyl sulfoximines exhibited the greatest activity, with LC50 values as low as 1 ppm. CONCLUSIONS: The novel series of N-heterocyclic sulfoximines helped to advance the current knowledge of the sulfoxaflor SAR, and demonstrated that the structural requirement for the sulfoximine nitrogen position was not limited to small, electron-deficient moeities, but rather was tolerant of larger functionality.


Subject(s)
Aphids/drug effects , Insecticides/chemical synthesis , Pyridines/chemical synthesis , Sulfur Compounds/chemical synthesis , Animals , Insecticides/pharmacology , Pyridines/pharmacology , Structure-Activity Relationship , Sulfur Compounds/pharmacology
7.
Bioorg Med Chem ; 17(12): 4230-40, 2009 Jun 15.
Article in English | MEDLINE | ID: mdl-19464188

ABSTRACT

The discovery of the sulfonamide herbicides, which inhibit the enzyme acetolactate synthase (ALS), has resulted in many investigations to exploit their herbicidal activity. One area which proved particularly productive was the N-aryltriazolo[1,5-c]pyrimidine sulfonamides, providing three commercial herbicides, cloransulam-methyl, diclosulam and florasulam. Additional structure-activity investigations by reversing the sulfonamide linkage resulted in the discovery of triazolopyrimidine sulfonamides with cereal crop selectivity and high levels of grass and broadleaf weed control. Research efforts to exploit these high levels of weed activity ultimately led to the discovery of penoxsulam, a new herbicide developed for grass, sedge and broadleaf weed control in rice. Synthetic efforts and structure-activity relationships leading to the discovery of penoxsulam will be discussed.


Subject(s)
Herbicides/chemistry , Pyrimidines/chemistry , Sulfonamides/chemistry , Uridine/analogs & derivatives , Acetolactate Synthase/antagonists & inhibitors , Acetolactate Synthase/metabolism , Crops, Agricultural , Drug Discovery , Herbicides/chemical synthesis , Herbicides/pharmacology , Pyrimidines/chemical synthesis , Pyrimidines/pharmacology , Structure-Activity Relationship , Sulfonamides/chemical synthesis , Sulfonamides/pharmacology , Uridine/chemical synthesis , Uridine/chemistry , Uridine/pharmacology
8.
Ground Water ; 47(4): 515-25, 2009.
Article in English | MEDLINE | ID: mdl-19341370

ABSTRACT

This paper describes a combined field, laboratory, and numerical study of electromagnetic borehole flowmeter measurements acquired without the use of a packer or skirt to block bypass flow around the flowmeter. The most significant finding is that inflow through the wellbore screen changes the ratio of flow through the flowmeter to wellbore flow. Experiments reveal up to a factor of two differences in this ratio for conditions with and without inflow through the wellbore screen. Standard practice is to assume the ratio is constant. A numerical model has been developed to simulate the effect of inflow on the flowmeter. The model is formulated using momentum conservation within the borehole and around the flowmeter. The model is embedded in the MODFLOW-2000 ground water flow code.


Subject(s)
Environmental Monitoring/methods , Water Movements
9.
Dig Dis Sci ; 53(1): 256-61, 2008 Jan.
Article in English | MEDLINE | ID: mdl-17549632

ABSTRACT

Celiac disease (CD) has been epidemiologically associated with chronic hepatitis C (HCV), and CD activation after the initiation of interferon (IFN-alpha) in patients with HCV is documented. However, clear association of CD and HCV is lacking. A prospectively maintained database of 878 CD patients showed a prevalence of 0.68% (six patients). Symptoms of diarrhea, weight loss, and depression prompted the diagnosis of CD during or after IFN-alpha therapy in four cases. Also, 294 subjects with liver disease (195 with HCV, 80 normal controls and 19 disease controls) were prospectively screened for CD. The mean age of the subjects was 50.1 years (SD 12.3), 58% males:42% females. A total of 30% received IFN-alpha therapy (16% at the time of testing for CD). Two HCV patients (1%) had positive tTG-IgA but these had negative endomysial antibody (EMA) and normal duodenal biopsies. CD prevalence is not increased in patients with HCV. Routine screening of CD in HCV patients is not warranted, however, the presence of CD should be considered in the setting of clinical deterioration during or after IFN-alpha therapy.


Subject(s)
Celiac Disease/etiology , Hepacivirus/immunology , Hepatitis C Antibodies/immunology , Hepatitis C, Chronic/complications , Adult , Antiviral Agents/therapeutic use , Celiac Disease/epidemiology , Cross-Sectional Studies , Female , Hepatitis C, Chronic/drug therapy , Hepatitis C, Chronic/epidemiology , Humans , Interferon-alpha/therapeutic use , Male , Middle Aged , New York/epidemiology , Prevalence , Prognosis , Prospective Studies , Risk Factors
10.
Hepatology ; 44(2): 335-40, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16871569

ABSTRACT

The low-density lipoprotein receptor (LDLR) has been proposed as a candidate receptor for the hepatitis C virus (HCV). Competitive inhibition of HCV binding to the LDLR by low-density lipoprotein (LDL) has been shown in vitro. If similar inhibition occurs in vivo, an elevated serum concentration of beta-lipoproteins may reduce the efficiency of infecting hepatocytes with HCV by competitively inhibiting HCV viral receptor binding. We investigated the role of baseline lipid values in influencing the outcome of HCV treatment. We conducted a retrospective chart review of patients treated with an interferon-based regimen at our liver and gastroenterology clinics between 1998 and 2004. Of 99 patients enrolled in the study, 49 (49.5%) had HCV genotype 1 (LDL 100.2 +/- 30.2 mg/dL [mean +/- SD]), and 50 patients (50.5%) had genotype 2 or 3 (LDL 110.1 +/- 40 mg/dL) infection. Early viral response (EVR), end-of-treatment response (ETR), and sustained viral response (SVR) were documented in 99, 88, and 77 patients, respectively. LDL and cholesterol levels prior to treatment were found to be higher in patients with positive EVR, ETR, and SVR. This difference remained significant independent of age. Multivariate analysis controlling for genotype and age showed that the higher the cholesterol and LDL levels prior to treatment, the greater the odds of responding to treatment. In conclusion, having higher serum LDL and cholesterol levels before treatment may be significant prognostic indicators for treatment outcome of those with chronic hepatitis C infection, particularly in genotypes 1 and 2.


Subject(s)
Antiviral Agents/therapeutic use , Hepatitis C, Chronic/blood , Interferons/therapeutic use , Lipoproteins, LDL/blood , Ribavirin/therapeutic use , Biomarkers/blood , DNA, Viral/genetics , Drug Therapy, Combination , Female , Follow-Up Studies , Genotype , Hepacivirus/drug effects , Hepacivirus/genetics , Hepatitis C, Chronic/drug therapy , Hepatitis C, Chronic/virology , Humans , Male , Middle Aged , Retrospective Studies , Treatment Outcome
11.
Clin Gastroenterol Hepatol ; 2(10): 888-94, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15476152

ABSTRACT

BACKGROUND & AIMS: Celiac disease is a polygenic disorder associated with HLA-DQ2 or HLA-DQ8, which are present in greater than 90% of patients. The disease is considered milder in the United States compared with Europe. We assessed whether differences in the frequency of HLA type may account for differences in severity of the disease by using cohorts of patients from New York and Paris. METHODS: HLA-DQ typing was performed on patients with celiac disease in New York and Paris. Clinical and pathologic data were compared between the New York and Parisian cohorts and also correlated with the different HLA types (HLA-DQ2, HLA-DQ2/-DQ8, HLA-DQ8). RESULTS: Among these patients, the disease was milder in the New York cohort compared with the Parisian cohort. There were fewer patients with a classical presentation (45% and 89%, respectively; P < 0.001) and less severe pathology (total villous atrophy, 64% and 89%, respectively; P < 0.05), and less marked intraepithelial lymphocytosis (intraepithelial leukocytes [IELs]/100 enterocytes, 48.1 and 82.5, respectively; P < 0.0001). HLA-DQ2 homozygotes were less prevalent in the New York cohort compared with the Parisian cohort (59% and 79%, respectively; P = 0.08). HLA-DQ8 alleles were more prevalent in the New York cohort compared with the Parisian cohort (41% and 21%, respectively; P = 0.026). There was, however, no difference in the clinical or pathologic parameters of severity when we compared the groups based on HLA type. CONCLUSIONS: HLA-DQ8 alleles were increased in the New York cohort of patients with celiac disease; however, this did not account for less severe manifestations of the disease.


Subject(s)
Celiac Disease/genetics , Celiac Disease/immunology , HLA-DQ Antigens/genetics , Severity of Illness Index , Adult , Atrophy/pathology , Case-Control Studies , Celiac Disease/pathology , Diarrhea/epidemiology , Diarrhea/etiology , Ethnicity , Female , Homozygote , Humans , Intestinal Mucosa/cytology , Intestine, Small/pathology , Lymphocytes/metabolism , Male , Microvilli/pathology , Middle Aged , Mitosis , New York City/epidemiology , Paris/epidemiology , Prospective Studies
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