Portable mass spectrometry for the direct analysis and quantification of volatile halogenated hydrocarbons in the gas phase

2017 ◽  
Vol 9 (6) ◽  
pp. 910-920 ◽  
Author(s):  
Stamatios Giannoukos ◽  
Mariya Juno Antony Joseph ◽  
Stephen Taylor
Keyword(s):  
Public Health ◽  
Mass Spectrometry ◽  
Gas Phase ◽  
Negative Impact ◽  
Stratospheric Ozone ◽  
Direct Analysis ◽  
Halogenated Hydrocarbons ◽  
Significant Negative Impact ◽  
Widespread Interest ◽  
Volatile Halogenated Hydrocarbons

Field chemical analysis (FCA) of volatile halogenated hydrocarbons is a highly debated topic of widespread interest due to the significant negative impact of these compounds on public health, on ecosystems and in the environment (e.g. destruction of the stratospheric ozone).

scholarly journals Formation of Highly Oxygenated Low-Volatility Products from Cresol Oxidation

2016 ◽  
Author(s):  
Rebecca H. Schwantes ◽  
Katherine A. Schilling ◽  
Renee C. McVay ◽  
Hanna Lignell ◽  
Matthew M. Coggon ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Gas Phase ◽  
Ring Opening ◽  
Chemical Ionization ◽  
First Generation ◽  
Direct Analysis ◽  
Organic Aerosol ◽  
Oxidation Products ◽  
Ionization Mass ◽  
Particle Phase

Abstract. Hydroxyl radical (OH) oxidation of toluene produces the ring-retaining products cresol and benzaldehyde, and the ring-opening products bicyclic intermediate compounds and epoxides. Here, first- and later-generation OH oxidation products from cresol and benzaldehyde are identified in laboratory chamber experiments. For benzaldehyde, first-generation ring-retaining products are identified, but later-generation products are not detected. For cresol, low-volatility (saturation mass concentration, C* ~ 3.5 × 104–7.7 × 10−3 μg m−3) first- and later-generation ring-retaining products are identified. Subsequent OH addition to the aromatic ring of o-cresol leads to compounds such as hydroxy, dihydroxy, and trihydroxy methyl benzoquinones and dihydroxy, trihydroxy, tetrahydroxy, and pentahydroxy toluenes. These products are detected in the gas phase by chemical ionization mass spectrometry (CIMS) and in the particle phase using offline direct analysis in real time mass spectrometry (DART-MS). Our data suggest that the yield of trihydroxy toluene from dihydroxy toluene is substantial. While an exact yield cannot be reported as authentic standards are unavailable, we find that a yield for trihydroxy toluene from dihydroxy toluene of ~ 0.7 (equal to the yield of dihydroxy toluene from o-cresol) is consistent with experimental results for o-cresol oxidation under low-NO conditions. These results suggest that even though the cresol pathway accounts for only ~ 20 % of the oxidation products of toluene, it is the source of a significant fraction (~ 20–40 %) of toluene secondary organic aerosol (SOA) due to the formation of low-volatility products.

Nonfinancial Information and Accounting: A Reconsideration of Benefits and Challenges

2009 ◽  
Vol 23 (3) ◽  
pp. 307-325 ◽  
Author(s):  
Joan Luft
Keyword(s):  
Measurement Error ◽  
Measurement Errors ◽  
Negative Impact ◽  
Firm Valuation ◽  
Nonfinancial Information ◽  
Nonfinancial Measures ◽  
Nonfinancial Performance ◽  
Significant Negative Impact ◽  
Portfolio Approach ◽  
Widespread Interest

SYNOPSIS: Recent years have seen widespread interest in supplementing or replacing accounting information with nonfinancial information (NFI) in a variety of uses such as incentive compensation, prediction of costs and profits, and firm valuation. The joint use of NFI and accounting has had mixed results, however. Research has documented benefits to such use but has also documented significant challenges. This commentary summarizes research that addresses two particularly important challenges in using combinations of accounting and NFI: measuring nonfinancial performance accurately and weighting measures appropriately when multiple accounting and nonfinancial measures are used together. These challenges are related, in that the nature and magnitude of measurement error helps to determine appropriate weights on multiple measures. Two common themes appear in strategies for dealing successfully with these challenges. The first is that matching information properties to decision types can limit the need for costly or infeasible improvements in measurement. Measurement errors that have significant negative impact on some decisions can be innocuous when the information is used for other decisions. The second theme is a portfolio approach to measurement error: the negative decision effects of error in individual measures can be significantly mitigated by well-chosen combinations of NFI and accounting measures.

scholarly journals Formation of highly oxygenated low-volatility products from cresol oxidation

2017 ◽  
Vol 17 (5) ◽  
pp. 3453-3474 ◽  
Author(s):  
Rebecca H. Schwantes ◽  
Katherine A. Schilling ◽  
Renee C. McVay ◽  
Hanna Lignell ◽  
Matthew M. Coggon ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Gas Phase ◽  
Ring Opening ◽  
Chemical Ionization ◽  
First Generation ◽  
Direct Analysis ◽  
Organic Aerosol ◽  
Oxidation Products ◽  
Ionization Mass ◽  
Particle Phase

Abstract. Hydroxyl radical (OH) oxidation of toluene produces ring-retaining products: cresol and benzaldehyde, and ring-opening products: bicyclic intermediate compounds and epoxides. Here, first- and later-generation OH oxidation products from cresol and benzaldehyde are identified in laboratory chamber experiments. For benzaldehyde, first-generation ring-retaining products are identified, but later-generation products are not detected. For cresol, low-volatility (saturation mass concentration, C* ∼ 3.5  ×  104 − 7.7  ×  10−3 µg m−3), first- and later-generation ring-retaining products are identified. Subsequent OH addition to the aromatic ring of o-cresol leads to compounds such as hydroxy, dihydroxy, and trihydroxy methyl benzoquinones and dihydroxy, trihydroxy, tetrahydroxy, and pentahydroxy toluenes. These products are detected in the gas phase by chemical ionization mass spectrometry (CIMS) and in the particle phase using offline direct analysis in real-time mass spectrometry (DART-MS). Our data suggest that the yield of trihydroxy toluene from dihydroxy toluene is substantial. While an exact yield cannot be reported as authentic standards are unavailable, we find that a yield for trihydroxy toluene from dihydroxy toluene of ∼ 0.7 (equal to the reported yield of dihydroxy toluene from o-cresol; Olariu et al., 2002) is consistent with experimental results for o-cresol oxidation under low-NO conditions. These results suggest that even though the cresol pathway accounts for only ∼ 20 % of the oxidation products of toluene, it is the source of a significant fraction (∼ 20–40 %) of toluene secondary organic aerosol (SOA) due to the formation of low-volatility products.

scholarly journals The Impact of the Coronavirus Disease 2019 Pandemic on Investor Sentiment—Evidence From A-Share Listed Companies in China

2021 ◽  
Vol 12 ◽  
Author(s):  
Yuegang Song ◽  
Xiazhen Hao ◽  
Zhou Lu
Keyword(s):  
Public Health ◽  
Panel Data ◽  
Financial Market ◽  
Negative Impact ◽  
Positive Impact ◽  
Investor Sentiment ◽  
Public Health Emergencies ◽  
Significant Negative Impact ◽  
Heterogeneity Analysis ◽  
The Impact

In a DID model, this study examines the impact of the coronavirus disease 2019 (COVID-19) pandemic on the investor sentiment in the financial market of China using monthly panel data on newly listed Chinese companies between October 2019 and June 2020. The outbreak of the pandemic is shown to exert a significant negative impact on investor sentiment. A future industry heterogeneity analysis shows that the pandemic has driven up investor sentiment in the pharmaceutical sector while having a significantly negative impact on non-pharmaceutical sectors. The pandemic is shown to have a negative impact on the private sector and foreign-invested sector in China while a significantly positive impact on the state-owned sector. This study contributes to the existing literature on the investigation of how significant the impact of public health emergencies on investor sentiment is.

scholarly journals Impact of the COVID-19 Pandemic on Cancer Diagnoses in General and Specialized Practices in Germany

Cancers ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 408
Author(s):  
Louis Jacob ◽  
Sven H. Loosen ◽  
Matthias Kalder ◽  
Tom Luedde ◽  
Christoph Roderburg ◽  
...  
Keyword(s):  
Public Health ◽  
Cancer Diagnosis ◽  
Negative Impact ◽  
Age Groups ◽  
Newly Diagnosed ◽  
Health Measures ◽  
Significant Negative Impact ◽  
Almost All ◽  
The Impact ◽  
Nose And Throat

The aim of this retrospective study was to investigate the impact of the coronavirus disease 2019 (COVID-19) pandemic on cancer diagnosis in general and specialized practices in Germany. This study included a total of 102,009 patients aged ≥18 years newly diagnosed with cancer in 1660 practices in Germany from January to May 2019 and from January to May 2020. Practices included general, gynecology, ear, nose, and throat (ENT), dermatology, and urology practices. New cancer diagnoses included all types of cancer and corresponded to cancers not previously documented in the database for a given patient. The number of new cancer diagnoses per general practice decreased significantly between March and May 2020 compared with the same period in 2019 (March: −12.0%, April: −27.6%, and May: −23.4%). A similar trend was observed in specialized practices, and this trend was more pronounced in April 2020 (dermatology: −44.4%, gynecology: −32.0%, and ENT: −28.2%). In addition, there was a significant decrease in almost all sex and age groups in April and May 2020 compared with the same period in 2019. Finally, the decrease in the number of new cancer diagnoses was particularly pronounced among cancers of the skin and the respiratory and intrathoracic organs. Together, these data show that the COVID-19 pandemic had a significant negative impact on cancer diagnosis in Germany, highlighting the need for public health measures improving the management of cancer in this country during this ongoing pandemic.

Comparison of Time spent between an electronic and a paper-based laboratory information system by laboratorians at a polyclinic in Greater Accra, Ghana: A time-motion study

2020 ◽  
Author(s):  
Philip Boakye
Keyword(s):  
Information System ◽  
Negative Impact ◽  
Laboratory Information System ◽  
Time Motion ◽  
Accessible Information ◽  
Motion Study ◽  
Significant Difference ◽  
Significant Negative Impact ◽  
Key Issues ◽  
Motion Studies

The acceptance of electronic laboratory information system (LIS) is gradually increasing in developing countries. However, the issue of time effectiveness due to computerization is less clear as there is fewer accessible information. One of the key issues for laboratorians is their indecision with LISs’ would-be effect of time on their work. A polyclinic in Ghana was in the process of implementing electronic LIS. Several of the laboratorians did not have knowledge and skill in computing and there were disagreeing views on the time effectiveness of the LIS after implementation. The management of the polyclinic laboratory was concerned to assess time advantageousness of recording data when using the electronic LIS compared with paper-based LIS. <div><br></div><div>Five randomly selected laboratorians were provided two sheets of paper with tables to document the time they spent for both paper-based and electronic LIS. Data were collected for a total of 230 records,115 electronic LIS and 115 paper-based LIS. The t-test (mean-comparison test) was computed to compare the means of both electronic and paperbased LIS times. </div><div><br></div><div>There was a statistical significant difference in the time spent between electronic and paper-based LIS. The time spent between paper-based and electronic LIS was 0.41 minutes (95% CI 0.15 to 0.66) longer than in electronic LIS. </div><div><br></div><div>LIS can be adopted in polyclinics without having significant negative impact on time spent between electronic and paper-based LIS. More time–motion studies that include laboratorians are however necessary in order to get a more complete picture of time spent between electronic and paper-based LIS. </div>

ASSESSMENT OF THE SPATIOTEMPORAL DYNAMICS OF THE MACROPHYTE THICKET ECOSYSTEMS IN THE NEVA BAY AND THE ADJACENT WATERS OF THE EASTERN GULF OF FINLAND

2017 ◽  
Author(s):  
Ekaterina Maksimova ◽  
Ekaterina Maksimova ◽  
Vladimir Zhigulsky ◽  
Vladimir Zhigulsky ◽  
Vladimir Shuisky ◽  
...  
Keyword(s):  
Aquatic Vegetation ◽  
Temporal Dynamics ◽  
Negative Impact ◽  
Spatiotemporal Dynamics ◽  
Gulf Of Finland ◽  
Active Growth ◽  
Nesting Sites ◽  
Significant Negative Impact ◽  
And Migration ◽  
Neva Bay

The macrophyte thicket ecosystems of higher aquatic vegetation in the Neva Bay (NB) and Eastern Gulf of Finland (EGoF) perform many important roles, including acting as the habitats, nesting sites and migration sites for aquatic and semi-aquatic birds, creating the specific conditions necessary for the spawning and growth of many species of fish, and taking part in the self-purification of the aquatic ecosystems. Many anthropogenic disturbances, hydraulic works in particular, have a significant negative impact on these macrophyte thicket ecosystems. In recent years, the active growth of a new type of macrophyte thicket has been observed in the NB. This is due to the aftereffects of the construction of the Saint Petersburg Flood Prevention Facility Complex (FPFC). It is quite likely that the total macrophyte thicket area in these waters is currently increasing. In the future, it will be necessary to assess the environmental impacts of the hydraulic works on the macrophyte thicket of the NB and EGoF, taking into account the background processes of the spatiotemporal dynamics of the reed beds in the waters in question. To do this, it will be necessary to carry out a comprehensive study of these ecosystems and identify patterns in their spatial and temporal dynamics. The program of the study has been developed and is currently being implemented by Eco-Express-Service, a St. Petersburg eco-design company.

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