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Open AccessEditorial
Welcome to Chemistry—An International Open Access Journal
Chemistry 2019, 1(1), 2; https://doi.org/10.3390/chemistry1010002 (registering DOI) -
Abstract
It is a great pleasure to welcome you to Chemistry—An International Journal. [...] Full article
Open AccessEditorial
Publisher's Notice: Chemistry—An International Journal
Chemistry 2019, 1(1), 1; https://doi.org/10.3390/chemistry1010001 (registering DOI) -
Abstract
MDPI is launching Chemistry—An International Journal [...] Full article
Open AccessArticle
Photochemical Reactions in Dialdehyde Starch
Molecules 2018, 23(12), 3358; https://doi.org/10.3390/molecules23123358 (registering DOI) -
Abstract
In this study potato and corn starch were subjected to oxidation, using sodium periodate, to obtain dialdehyde starch (DAS) containing different amount of aldehyde groups. The obtained modified starch samples have been characterized with chemical analysis, scanning electron microscopy (SEM) and ATR-FTIR spectroscopy.
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In this study potato and corn starch were subjected to oxidation, using sodium periodate, to obtain dialdehyde starch (DAS) containing different amount of aldehyde groups. The obtained modified starch samples have been characterized with chemical analysis, scanning electron microscopy (SEM) and ATR-FTIR spectroscopy. Then, the samples were exposed to polychromatic UV radiation and the course of photochemical reaction has been monitored with ATR-FTIR spectroscopy. The surface properties of the native and dialdehyde starch before and after UV-irradiation have been determined by contact angle measurements and calculation of surface free energy. The crystallinity of the samples has been estimated with X-ray diffraction (XRD). It has been proved that the dialdehyded corn starch contained a higher amount of functional groups was more photostable than the oxidized potato starch. Sodium iodide(V), firmly bound to DAS macromolecules, has been found to have a significant effect on the photooxidative degradation of the tested systems. In addition, the mechanism of photoinduced reactions in the dialdehyde starch has been proposed. Full article
Open AccessArticle
Fragmented Nuclear DNA is the Predominant Genetic Material in Human Hair Shafts
Genes 2018, 9(12), 640; https://doi.org/10.3390/genes9120640 (registering DOI) -
Abstract
While shed hairs are one of the most commonly encountered evidence types, they are among the most limited in terms of DNA quantity and quality. As a result, nuclear DNA short tandem repeat (STR) profiling is generally unsuccessful and DNA testing of shed
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While shed hairs are one of the most commonly encountered evidence types, they are among the most limited in terms of DNA quantity and quality. As a result, nuclear DNA short tandem repeat (STR) profiling is generally unsuccessful and DNA testing of shed hair is instead performed by targeting the mitochondrial DNA control region. Although the high copy number of mitochondrial DNA relative to nuclear DNA routinely permits the recovery of mitochondrial DNA (mtDNA) data in these cases, mtDNA profiles do not offer the discriminatory power of nuclear DNA profiles. In order to better understand the total content and degradation state of DNA in single shed hairs and assess the feasibility of recovering highly discriminatory nuclear DNA data from this common evidence type, high throughput shotgun sequencing was performed on both recently collected and aged (approximately 50-year-old) hair samples. The data reflect trends that have been demonstrated previously with other technologies, namely that mtDNA quantity and quality decrease along the length of the hair shaft. In addition, the shotgun data reveal that nuclear DNA is present in shed hair and surprisingly abundant relative to mitochondrial DNA, even in the most distal fragments. Nuclear DNA comprised, at minimum, 88% of the total human reads in any given sample, and generally more than 95%. Here, we characterize both the nuclear and mitochondrial DNA content of shed hairs and discuss the implications of these data for forensic investigations. Full article
Open AccessArticle
Qualitative and Quantitative Analysis of C-glycosyl-flavones of Iris lactea Leaves by Liquid Chromatography/Tandem Mass Spectrometry
Molecules 2018, 23(12), 3359; https://doi.org/10.3390/molecules23123359 (registering DOI) -
Abstract
Iris lactea Pall. var. chinensis (Fisch.) Koidz. is a traditional medicinal plant resource. To make full use of the I. lactea plant resources, constituents of I. lactea leaves were determined by high performance liquid chromatography (HPLC)-quadrupole time-of-flight tandem mass spectrometry and 22 C
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Iris lactea Pall. var. chinensis (Fisch.) Koidz. is a traditional medicinal plant resource. To make full use of the I. lactea plant resources, constituents of I. lactea leaves were determined by high performance liquid chromatography (HPLC)-quadrupole time-of-flight tandem mass spectrometry and 22 C-glycosylflavones were identified or tentatively identified. Optimal extraction of I. lactea leaves was established via single factor investigations combined with response surface methodology. Then, HPLC coupled with a diode array detector was used to quantitatively analyze the six main components of 14 batches of I. lactea leaves grown in different areas. The results showed the C-glycosylflavones were the main components of I. lactea leaves, and the total contents of detected components were relatively stable for the majority of samples. These results provide a foundation for the development and utilization of I. lactea leaves. Full article
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Open AccessArticle
Open Innovation Session as a Tool Supporting Innovativeness in Strategies for High-Tech Companies in the Czech Republic
Economies 2018, 6(4), 69; https://doi.org/10.3390/economies6040069 (registering DOI) -
Abstract
Open innovation has developed over several decades from a small pool of innovation pioneers, mostly active in high-tech industries, to be widely discussed and implemented in innovation strategy. The primary objective of the Open Innovation Session (OIS) is to create a platform where
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Open innovation has developed over several decades from a small pool of innovation pioneers, mostly active in high-tech industries, to be widely discussed and implemented in innovation strategy. The primary objective of the Open Innovation Session (OIS) is to create a platform where firms are able to facilitate knowledge transfer. This paper focuses on the contribution of OIS, implemented by regional government, in formulating companies’ strategic management and to overcome barriers to innovation for high-tech companies in the South Moravian region of the Czech Republic. The methodology adopted for this paper includes monitoring and analysing the activities of this programme over seven years, followed by a quantitative study using both primary and secondary data. The primary data for the research were gathered through questionnaires, where the respondents were general managers of companies that had at least some experience of an innovation process. Secondary data were taken from the Czech Statistical Office. This paper has found that the association between an aspiration for innovation leadership and expenditure for research and development is high, further that participation in OIS led to a shift in the perception of the objectives, needs and conditions of the business and finally the major barriers to the innovation process are a lack of highly motivated people with the necessary technical and business experience. Full article
Open AccessArticle
The Mediating Roles of Happiness and Cohesion in the Relationship between Employee Volunteerism and Job Performance
Int. J. Environ. Res. Public Health 2018, 15(12), 2903; https://doi.org/10.3390/ijerph15122903 (registering DOI) -
Abstract
This study investigated the mediating effects of happiness and cohesion in the relationship between employee volunteerism, in-role behavior, and helping behavior. The study surveyed 312 full-time employees in South Korea, and regression analyses and the bootstrapping method were used to test the hypotheses.
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This study investigated the mediating effects of happiness and cohesion in the relationship between employee volunteerism, in-role behavior, and helping behavior. The study surveyed 312 full-time employees in South Korea, and regression analyses and the bootstrapping method were used to test the hypotheses. The study found happiness and cohesion to mediate the relationships between employee volunteerism and in-role and helping behavior. The findings suggest that employee volunteerism can promote a healthy working environment through increased feelings of happiness and cohesion as well as by improving performance behaviors. Full article
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Open AccessArticle
Activation of Polyamine Catabolism by N1,N11-Diethylnorspermine in Hepatic HepaRG Cells Induces Dedifferentiation and Mesenchymal-Like Phenotype
Cells 2018, 7(12), 275; https://doi.org/10.3390/cells7120275 (registering DOI) -
Abstract
Tumorigenesis is accompanied by the metabolic adaptation of cells to support enhanced proliferation rates and to optimize tumor persistence and amplification within the local microenvironment. In particular, cancer cells exhibit elevated levels of biogenic polyamines. Inhibitors of polyamine biosynthesis and inducers of their
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Tumorigenesis is accompanied by the metabolic adaptation of cells to support enhanced proliferation rates and to optimize tumor persistence and amplification within the local microenvironment. In particular, cancer cells exhibit elevated levels of biogenic polyamines. Inhibitors of polyamine biosynthesis and inducers of their catabolism have been evaluated as antitumor drugs, however, their efficacy and safety remain controversial. Our goal was to investigate if drug-induced modulation of polyamine metabolism plays a role in dedifferentiation using differentiated human hepatocyte-like HepaRG cell cultures. N1,N11-diethylnorspermine (DENSpm), a potent inducer of polyamine catabolism, triggered an epithelial-mesenchymal transition (EMT)-like dedifferentiation in HepaRG cultures, as shown by down-regulation of mature hepatocytes markers and upregulation of classical EMT markers. Albeit the fact that polyamine catabolism produces H2O2, DENSpm-induced de-differentiation was not affected by antioxidants. Use of a metabolically stable spermidine analogue showed furthermore, that spermidine is a key regulator of hepatocyte differentiation. Comparative transcriptome analyses revealed, that the DENSpm-triggered dedifferentiation of HepaRG cells was accompanied by dramatic metabolic adaptations, exemplified by down-regulation of the genes of various metabolic pathways and up-regulation of the genes involved in signal transduction pathways. These results demonstrate that polyamine metabolism is tightly linked to EMT and differentiation of liver epithelial cells. Full article
Open AccessFeature PaperArticle
Application of Palm Oil Biodiesel Blends under Idle Operating Conditions in a Common-Rail Direct-Injection Diesel Engine
Appl. Sci. 2018, 8(12), 2665; https://doi.org/10.3390/app8122665 (registering DOI) -
Abstract
This study describes the effects of palm oil biodiesel blended with diesel on the combustion performance, emission characteristics, and soot morphology in a 4-cylinder common-rail direct-injection (CRDI) diesel engine. The operational condition is idle speed, 750 rpm (the lowest speed of the test
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This study describes the effects of palm oil biodiesel blended with diesel on the combustion performance, emission characteristics, and soot morphology in a 4-cylinder common-rail direct-injection (CRDI) diesel engine. The operational condition is idle speed, 750 rpm (the lowest speed of the test engine without any operation by driver), and the load conditions of the engine are 0 Nm and 40 Nm. Five kinds of biodiesel fuels are blended with diesel in 0%, 10%, 20%, 30%, and 100% proportions by volume. A pilot injection was applied at BTDC 15 °CA and 20 °CA. Part of the pilot injection affects the combustion of the main injection due to the deterioration of the spray because of the high viscosity of palm oil biodiesel. Palm oil biodiesel is sufficient to keep the engine stable in an idling state, but the fuel economy deteriorated. The deterioration of the spray due to the high viscosity of palm oil biodiesel is offset by the effect of oxygen content and high cetane number, resulting in a constant nitric oxide (NOx) emission. However, particulate matter (PM) is reduced. When the engine load is increased, the carbon monoxide (CO) emission amount increased because of the insufficient intake air and oxygen content to reduce the fuel-rich areas. However, when the palm oil biodiesel blend ratio was above a certain level, the influence of oxygen content in the palm oil biodiesel increased, resulting in reduced CO emission levels. Hydrocarbon (HC) was reduced by oxygen atoms in palm oil biodiesel. The sizes of particulates emitted from diesel engine using palm oil biodiesel decreased with an increased blend ratio because of oxidization of hydrocarbons absorbed on PM. Full article
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Open AccessFeature PaperArticle
A General Model for Estimating Emissions from Integrated Power Generation and Energy Storage. Case Study: Integration of Solar Photovoltaic Power and Wind Power with Batteries
Processes 2018, 6(12), 267; https://doi.org/10.3390/pr6120267 (registering DOI) -
Abstract
The penetration of renewable power generation is increasing at an unprecedented pace. While the operating greenhouse gas (GHG) emissions of photovoltaic (PV) and wind power are negligible, their upstream emissions are not. The great challenge with the deployment of renewable power generators is
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The penetration of renewable power generation is increasing at an unprecedented pace. While the operating greenhouse gas (GHG) emissions of photovoltaic (PV) and wind power are negligible, their upstream emissions are not. The great challenge with the deployment of renewable power generators is their intermittent and variable nature. Current electric power systems balance these fluctuations primarily using natural gas fired power plants. Alternatively, these dynamics could be handled by the integration of energy storage technologies to store energy during renewable energy availability and discharge when needed. In this paper, we present a model for estimating emissions from integrated power generation and energy storage. The model applies to emissions of all pollutants, including greenhouse gases (GHGs), and to all storage technologies, including pumped hydroelectric and electrochemical storage. As a case study, the model is used to estimate the GHG emissions of electricity from systems that couple photovoltaic and wind generation with lithium-ion batteries (LBs) and vanadium redox flow batteries (VFBs). To facilitate the case study, we conducted a life cycle assessment (LCA) of photovoltaic (PV) power, as well as a synthesis of existing wind power LCAs. The PV LCA is also used to estimate the emissions impact of a common PV practice that has not been comprehensively analyzed by LCA—solar tracking. The case study of renewables and battery storage indicates that PV and wind power remain much less carbon intensive than fossil-based generation, even when coupled with large amounts of LBs or VFBs. Even the most carbon intensive renewable power analyzed still emits only ~25% of the GHGs of the least carbon intensive mainstream fossil power. Lastly, we find that the pathway to minimize the GHG emissions of power from a coupled system depends upon the generator. Given low-emission generation (<50 gCO2e/kWh), the minimizing pathway is the storage technology with lowest production emissions (VFBs over LBs for our case study). Given high-emission generation (>200 gCO2e/kWh), the minimizing pathway is the storage technology with highest round-trip efficiency (LBs over VFBs). Full article
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