bluuebunny/crossref_metadata_2025 huggingface dataset:
Timescales of secondary organic aerosols to reach equilibrium at various temperatures and relative humidities
Authors: Li Ying , Shiraiwa Manabu
Published: May 2019

Abstract. Secondary organic aerosols (SOA) account for a substantial fraction of air
particulate matter, and SOA formation is often modeled assuming rapid
establishment of gas–particle equilibrium. Here, we estimate the
characteristic timescale for SOA to achieve gas–particle equilibrium under
a wide range of temperatures and relative humidities using a
state-of-the-art kinetic flux model. Equilibration timescales were
calculated by varying particle phase state, size, mass loadings, and
volatility of organic compounds in open and closed systems. Model
simulations suggest that the equilibration timescale for semi-volatile
compounds is on the order of seconds or minutes for most conditions in the
planetary boundary layer, but it can be longer than 1 h if particles
adopt glassy or amorphous solid states with high glass transition
temperatures at low relative humidity. In the free troposphere with lower
temperatures, it can be longer than hours or days, even at moderate or
relatively high relative humidities due to kinetic limitations of bulk
diffusion in highly viscous particles. The timescale of partitioning of
low-volatile compounds into highly viscous particles is shorter compared to
semi-volatile compounds in the closed system, as it is largely determined by
condensation sink due to very slow re-evaporation with relatively quick
establishment of local equilibrium between the gas phase and the
near-surface bulk. The dependence of equilibration timescales on both
volatility and bulk diffusivity provides critical insights into
thermodynamic or kinetic treatments of SOA partitioning for accurate
predictions of gas- and particle-phase concentrations of semi-volatile
compounds in regional and global chemical transport models.
Mesospheric semidiurnal tides and near-12 h waves through jointly analyzing observations of five specular meteor radars from three longitudinal sectors at boreal midlatitudes
Authors: He Maosheng , Chau Jorge Luis
Published: May 2019

Abstract. In the last decades, mesospheric tides have been intensively investigated
with observations from both ground-based radars and satellites. Single-site
radar observations provide continuous measurements at fixed locations without
horizontal information, whereas single-spacecraft missions typically provide
global coverage with limited temporal coverage at a given location. In this
work, by combining 8 years (2009–2016) of mesospheric winds collected by
five specular meteor radars from three different longitudinal sectors at
boreal midlatitudes (49±8.5∘ N), we develop an approach to
investigate the most intense global-scale oscillation, namely at the period
T=12±0.5 h. Six waves are resolved: the semidiurnal westward-traveling
tidal modes with zonal wave numbers 1, 2, and 3 (SW1, SW2, SW3), the lunar
semidiurnal tide M2, and the upper and lower sidebands (USB and LSB) of the
16 d wave nonlinear modulation on SW2. The temporal variations of the waves
are studied statistically with a special focus on their responses to sudden
stratospheric warming events (SSWs) and on their climatological seasonal
variations. In response to SSWs, USB, LSB, and M2 enhance, while SW2
decreases. However, SW1 and SW3 do not respond noticeably to SSWs, contrary
to the broadly reported enhancements in the literature. The USB, LSB, and SW2
responses could be explained in terms of energy exchange through the
nonlinear modulation, while LSB and USB might previously have been
misinterpreted as SW1 and SW3, respectively. Besides, we find that LSB and M2
enhancements depend on the SSW classification with respect to the associated
split or displacement of the polar vortex. In the case of seasonal
variations, our results are qualitatively consistent with previous studies
and show a moderate correlation with an empirical tidal model derived from
satellite observations.
Employing correlation for wireless components and device characterization in reverberation chambers
Authors: Cammin Christoph , Krush Dmytro , Heynicke Ralf , Scholl Gerd
Published: May 2019

Abstract. Reverberation chambers are well-proven test environments for radio frequency (RF) measurements. Typically, mean values are taken from the measurements to characterize the equipment under test. In the novel approach presented in this paper, the correlation of measured sample sequences is utilized to detect deviations, in particular of the radiation characteristics, from reference equipment. This approach is exemplified by a measurement setup using several different antennas with the same housing. The complex correlation coefficient and the correlation coefficient with respect to the transferred power of two measured sample sequences are calculated and evaluated for a suitable frequency range to detect differences between the radiation characteristics.
Lyapunov analysis of multiscale dynamics: the slow bundle of the two-scale Lorenz 96 model
Authors: Carlu Mallory , Ginelli Francesco , Lucarini Valerio , Politi Antonio
Published: May 2019

Abstract. We investigate the geometrical structure of instabilities in the two-scale
Lorenz 96 model through the prism of Lyapunov analysis. Our detailed study of
the full spectrum of covariant Lyapunov vectors reveals the presence of a
slow bundle in tangent space, composed by a set of vectors with a
significant projection onto the slow degrees of freedom; they correspond
to the smallest (in absolute value) Lyapunov exponents and thereby to the
longer timescales. We show that the dimension of the slow bundle is extensive
in the number of both slow and fast degrees of freedom and discuss its
relationship with the results of a finite-size analysis of instabilities,
supporting the conjecture that the slow-variable behavior is effectively
determined by a nontrivial subset of degrees of freedom. More precisely, we
show that the slow bundle corresponds to the Lyapunov spectrum region where
fast and slow instability rates overlap, “mixing” their evolution into a
set of vectors which simultaneously carry information on both scales. We
suggest that these results may pave the way for future applications to
ensemble forecasting and data assimilations in weather and climate models.
Ascendants That Influence the Adoption of E-government Services among Citizen of Pakistan
Authors: Hammad Ali , Ahmad Intikhab , Sikander Syed Muhammad , Reyad Md Amjad Hossain , Kazmi Syed Mazahir
Published: May 2019

In this research study, the author seeks to discover the predecessors of e-government services adoption among the citizen of Pakistan. To study the e-government adoption, researcher integrates extended TAM and theory of planned behaviour. Cross-sectional research technique was used and in total data was collected from 240 citizens of Pakistan. Results depict that facilitating conditions, performance expectancy, effort expectancy positively impact the citizen attitude towards adoption of e-government facilities. As well as, facilitating conditions as a positive impact on society and individual computer self-efficacy which helps in building citizen attitude.Furthermore, the researcher studies the impact of government trust as a moderator to test the relationship between attitude and adoption of e-government services. Results show that government trust dampens down the relationship between attitude and e-government adoption. To the conclude results SEM technique was used using AMOS-21.
Study Factors Affecting the Level of Information Disclosure of Vietnamese Enterprises
Authors: Dang Hung Ngoc , Diep Pham Thi Hong , Binh Dang Thai
Published: May 2019

This study explores the status of information disclosure and the factors affecting the disclosure of information in the annual report of listed companies in the stock market of Vietnam This study uses a combination of weighting methods, assessing the level of published information of each criterion to measure the level of information disclosure both in terms of quantity and quality. The authors use a combined approach to measure the level of disclosure in the annual report of 289 enterprises in Vietnam. In which, the authors use to test the parameters and non-parametric testing of the level of disclosure of information under the industry and according to Big4 auditing firms. At the same time, in this research, the authors apply the OLS regression and quantile regression model to examine the effect of each factor on the level of information disclosure. Research shows that the level of disclosure in the annual report is 58.57%. The research has identified four factors that affect the level of disclosure: independent audit, enterprise size, profitability, financial leverage. However, there are two factors that do not affect the level of disclosure: the number of members of the board of directors and the Chairman & General Director. This result will suggest some recommendations to help businesses, agencies to improve the level of information disclosure.
Competing With Bitcoin - Some Policy Considerations for Issuing Digitalized Legal Tenders
Authors: Kovanen Arto
Published: May 2019

The proliferation of peer-to-peer virtual alternatives to traditional banknotes has raised concerns among policymakers about the future of traditional means of making payments and how it might affect monetary policy implementation and its effectiveness. This study provides a brief overview of the existing research in this area. It compares positions taken in the literature by authors on some of the key policy issues relevant for central banks when thinking about the issuance of digitalized legal tenders. We examine the implications of government issued digital alternatives to traditional currencies for monetary policy effectiveness, payments and settlements, and financial market stability. We also discuss recent advances in financial technology to improve the making of payments and settlements, which might help contribute to financial inclusion. At the same time, new technologies represent challenges for regulatory authorities, for instance related to efforts to contain anti-money laundering and prevent financing of terrorism. A number of authors argue that government issued digital currency is necessary to address the flaws in private crypto currencies, and to improve monetary policy effectiveness. Central banks have begun to analyze possible features of digitalized legal tenders, to better understand the policy considerations involved and effects these could have for interest rate transmission and financial markets, but there is no clear consensus on key modalities associated with digitalized legal tenders. Moreover, many central banks do not regard privately issued virtual currencies as a serious threat to traditional currencies. Given the ongoing debate, it is difficult to make firm predictions about the impact of central bank issued digital currencies on monetary policy transmission and financial markets at this point.
Effect of supplementation with Escherichia coli phytase for broilers on performance, nutrient digestibility, minerals in the tibia and diet cost
Authors: Dessimoni Gabriel Villela , Sakomura Nilva Kazue , Donato Daniella Carolina Zanardo , Goldflus Fábio , Ferreira Nayara Tavares , Dalólio Felipe Santos
Published: May 2019

Although phytase has been researched, new enzymes have been produced, leading to different animal responses. In this scenario, the present study proposes to evaluate the inclusion of a bacterial phytase produced by Escherichia coli in broiler diets based on corn and soybean meal, with or without nutrient reductions, on the performance, nutrient digestibility, phosphorus bioavailability, and bone minerals of those animals and on the economic viability of this practice. A total of 896 male broiler chickens were distributed into 32 experimental units, each housing 28 broilers. The experiment was set up as a completely randomized design with four treatments (Positive Control (PC)- diet meeting the nutritional requirements of the broiler chickens; Negative Control (NC) with reductions of 100kcal/kg of ME, 0.14% avP and 0.11% tCa; NC + phytase (500 FTU/kg); PC + phytase (500FTU/kg)) and 8 replicates. Phytase increased (p < 0.05) feed intake and body weight gain and improved feed conversion ratio in starter (1 to 21 days) and total (1 to 42 days) phases, respectively, compared with Negative Control diet without supplementation. The Negative Control + phytase diet also led to a feed intake similar to Positive Control in the starter and total phases. The inclusion of phytase without nutrient reductions improved (p < 0.05) feed conversion ratio in the starter phase, compared to Positive Control diet. There was an increase (p < 0.05) in the digestibility of dry matter, crude protein and phosphorus and in apparent digestible energy in the Negative Control + phytase diet compared to the Negative Control diet. Phytase supplementation increased (p < 0.05) the digestibility of crude protein, calcium and phosphorus, and apparent digestible energy compared to Positive Control diet. Ash, phosphorus, and calcium contents were higher in the Negative Control + phytase diet compared with those observed in the Negative Control diet without enzyme (p < 0.05). The Positive Control + phytase diet provided higher ash contents (p < 0.05), but calcium and phosphorus deposition was similar to those obtained with Positive Control diet. Phytase inclusion allows for a reduction in the diet cost per ton of produced feed. In conclusion, dietary supplementation with bacterial phytase produced from Escherichia coli for broiler chickens is recommended, as it provided increases in production performance, nutrient digestibility, and energy metabolizability and a reduction in the diet cost.
Investigating Students’ and Staff Members’ Attitudes Toward the Efficiency of the Language Skills Modules Offered During the Foundation Year
Authors: Dashti Abdulmohsen A.
Published: May 2019

In the scope of teaching English as a foreign language, and more specifically teaching speaking, reading, and writing, this study investigated the attitudes English language teachers-to-be have towards the three language skills modules, namely, Conversation, Reading, and Basic writing, offered by the College of Basic Education (hereafter CBE) in Kuwait. It also investigated the concerns of staff members at the English department in CBE with regards to the matter. The study utilized two questionnaires, one distributed to the students’ population, i.e., English major students (the sample received was (N 385), and the other one distributed to all staff members in the English department in CBE (N 27). In addition, 20 students were randomly selected and interviewed to verify the questionnaires’ results. The data, then, were analysed both quantitatively and qualitatively. Percentages, means and standard deviations were calculated together with t test and ANOVA. Results showed that even though most students and staff members showed positive attitudes towards most of the questionnaires’ items, others were concerned about a few items.
Evaluating the Financial Soundness of Small and Medium-Sized Commercial Banks in Kenya: An Application of the Bankometer Model
Authors: Ouma Moses O. , Kirori Gabriel N.
Published: May 2019

The study investigated the financial soundness of small and medium-sized commercial banks in Kenya over the four-year period, 2014 to 2017, using the bankometer model and further compared the financial health of the two bank categories. The study employed secondary data from a census of Twelve (12) medium-sized and Sixteen (16) small banks, with the financial soundness being proxied by the overall solvency score (S-Score) in order to achieve its objective. A total of six (6) different financial ratios namely, Capital to Assets ratio, Equity to Assets ratio, Capital Adequacy Ratio, Non-Performing Loans ratio, Operating Cost to Operating Income ratio and the ratio of Loans to Assets were used in the study to measure the degree of financial health of the banks. One of the key findings of the study was that both the small and medium-sized commercial banks in Kenya were financially sound during each of the four (4) years studied, with no significant difference in the financial soundness of the two bank categories. Other findings were that all the banks studied experienced poor performance in loans and operations while two banks had below the benchmark capital adequacy ratio. The findings of the study are important in that, they can be used to formulate policies and strategies for promoting improvement in the financial performance of the banking sector in particular and the business sector at large in the country.
PARLIAMENTARY MUSEUM: HISTORICAL
CONTEXTS AS WELL AS CULTURAL
AND POLITICAL ENTANGLEMENTS
Authors: Popławski Błażej
Published: May 2019

The goal of the article is to present
parliamentary museum as an institution. In the
introduction parliamentary museum is characterized
as a peculiar type of historical museum. Subsequently,
selected institutions of the kind in India, Japan, Jordan,
and Belgium are discussed. Moreover, the political context
for founding the Museum of the Polish Sejm [Parliament]
is described. This covers the time spanning from the late
1970s to 1989, as well as the operations of the Museum
Content Department at the Sejm Library. To conclude,
challenges and prospects for the planned Museum of
Polish Parliamentarism are presented.
Designing Student Reflections to Enable Transformative Learning Experiences
Authors: Flierl Michael , Hamer Russ ,   Philosophy Documentation Center
Published: May 2019

Many philosophy instructors want their students to change the way they think about and act in the world. Reflection can be one way to bring this about, yet it is common for student reflections to fail to enable this desired transformative learning experience. Our research investigated how instructors can design better reflective assignments to cultivate a more transformative learning experience for students. Using thematic analysis, a qualitative research method, we analyzed student reflection data to identify themes and patterns of student work. Findings include concrete guidelines for cultivating better student reflections, including: designing for reflection, explicitly limiting summary, and incentivizing students to make specific claims while bringing personal experience to bear.
Values of circulating molecular biomarkers (microRNAs) for the evaluation of renal failure during urgent abdominal sepsis anaesthesia
Authors: Bukauskas Tomas , Kairytė Monika , Mickus Rytis , Puleikytė Loreta , Macas Andrius
Published: May 2019

Background. Micro-ribonucleic acids (miRNAs) are small non-coding molecules important for gene regulation and management of physiological processes (1). Alterations in the expression of miRNAs are potential novel biomarkers for many diseases (2). Materials and methods. Random patients who underwent emergency surgery for abdominal sepsis were enrolled into the study (N = 27). Patients were divided into three groups according to the renal function and into two groups depending on the presence or the absence of lethal outcomes during the hospitalization period. Relative expression levels of circulating serum miR-30d-5p, miR-23a-3p, miR-146a-5p were assessed with real-time quantitative polymerase chain reaction using the 2–ΔΔCt method and compared between the groups. Results. Expression levels of all three miRNAs did not differ significantly between patients with acute renal failure (ARF) (n = 8), chronic renal failure (CRF) (n = 8), and with a normal renal function (NRF) (n = 11). Estimated glomerular filtration rates (eGFR) were significantly lower (p = 0.016), the values of urea (p = 0.007) and red blood cell distribution width (RDW) (p = 0.001) were significantly higher in septic patients who died, but no significant correlation between RDW values and expression of miRNAs was found. Conclusions. The expression levels of serum miR-30d-5p, miR-23a-3p, miR-146-5p did not significantly differ between three groups of patients who developed ARF, had CRF, or retained NRF. No significant association between the RDW value and expression of miRNAs was noted.
Development of an Efficient Extraction Method for Separating Solasodine, an Steroidal Alkaloid, From an Oily Matrix: A Comparison Between LLE and SPE
Authors: Khandani Shahram Kalantari , Mehrabani Mitra , Sharififar Fariba , Pardakhty Abbas , Pournamdari Mostafa
Published: May 2019

Aims: In many references of Traditional Iranian Medicine (TIM), there are methods to produce medicinal products from plant fruit based on extraction of active substances into oils. One of these recommendations is to import cucurbit or pumpkin seed oil into an entirely ripe fruit of Solanum melongena plant. In this study for the first time, the extraction of solasodine from the oily matrix has been investigated to find a precise method with suitable extraction recovery.

Study Design:  Original Research Article.

Place and Duration of Study: The study took place in herbal and traditional medicines research center of Kerman, Iran from February 2015 to November 2017.

Methodology: Solasodine, an active steroidal alkaloid metabolite of the plant, was used for standardization of the product. Two methods of (Liquid-liquid extraction) LLE and (Solid phase extraction) SPE were evaluated and their conditions were optimized by assessment of seven effective factors at five levels using HPLC as the method of choice for solasodine determination.

Results: Results showed that LLE and SPE in optimized conditions had recoveries of about 76.5 and 94.7%, respectively. For the extraction of low concentrations of the analyte, the SPE method had better accuracies (88 to 105%), but its precision was less than that of LLE method. In contrast, the LLE method had a higher precision in the whole range while its relevant accuracy was lower. The LOD and LOQ of SPE-HPLC method were 0.2 and 0.6 μg/ml and those of the LLE-HPLC method were 0.2 and 0.7 μg/ml, respectively.

Conclusion: In general, both methods of LLE-HPLC and SPE-HPLC showed acceptable validation parameters including linearity, precision, accuracy, LOD, and LOQ; and they can be used for routine extraction and determination of solasodine in traditional medicine products.
RNase L facilitates the repair of DNA double‐strand breaks through the nonhomologous end‐joining pathway
Authors: Zhong Yiran , Pan Bingxin , Zhu Jie , Fu Hanjiang , Zheng Xiaofei
Published: May 2019

RNA molecules have been found to play important roles in DNA double‐strand break (DSB) repair, but the exact underlying mechanism remains unclear. Here, we aimed to clarify the function of RNase L, an important ribonuclease in the immune system of vertebrates, in DSB repair. Knockdown of RNase L reduces cell survival after induction of DSBs by ionizing radiation or camptothecin and causes a significant decrease in DSB repair, as evidenced by an increase in the extent of phosphorylation of histone H2AX on Ser139 (γH2AX) and γH2AX nuclear foci formation. Thus, our findings indicate that RNase L interacts with the core factors involved in DNA end joining, such as XRCC4 and Lig4, and facilitates DSB repair through the nonhomologous end‐joining pathway.
Stretch Induces Invasive Phenotypes in Breast Cells Due to Activation of Aerobic‐Glycolysis‐Related Pathways
Authors: Ansaryan Saeid , Khayamian Mohammad Ali , Saghafi Mohammad , Shalileh Shahriar , Nikshoar Mohammad Saied , Abbasvandi Fereshteh , Mahmoudi Morteza , Bahrami Farideh , Abdolahad Mohammad
Published: May 2019

It is increasingly being accepted that cells' physiological functions are substantially dependent on the mechanical characteristics of their surrounding tissue. This is mainly due to the key role of biomechanical forces on cells and their nucleus' shapes, which have the capacity to regulate chromatin conformation and thus gene regulations. Therefore, it is reasonable to postulate that altering the biomechanical properties of tissue may have the capacity to change cell functions. Here, the role of cell stretching (as a model of biomechanical variations) is probed in cell migration and invasion capacity using human normal and cancerous breast cells. By several analyses (i.e., scratch assay, invasion to endothelial barrier, real‐time RNA sequencing, confocal imaging, patch clamp, etc.), it is revealed that the cell‐stretching process could increase the migration and invasion capabilities of normal and cancerous cells, respectively. More specifically, it is found that poststretched breast cancer cells are found in low grades of invasion; they substantially upregulate the expression of manganese‐dependent superoxide dismutase (MnSOD) through activation of H‐Ras proteins, which subsequently induce aerobic glycolysis followed by an overproduction of matrix metalloproteinases (MMP)‐reinforced filopodias. Presence of such invadopodias facilitates targeting of the endothelial layer, and increased invasive behaviors in breast cells are observed.
Guided Assembly of Microporous/Mesoporous Manganese Phosphates by Bifunctional Organophosphonic Acid Etching and Templating
Authors: Hu Yating , Zhang Yu , Li Changjian , Wang Ling , Du Yonghua , Mo Guang , Li Xu , Cheetham Anthony K. , Wang John
Published: May 2019

Manganese (Mn)‐based compounds are important materials for both energy conversion and energy storage. Unfortunately, it has been a significant challenge to develop highly ordered microporous/mesoporous structures for them to provide more active sites for these applications. In order to do so using the soft‐templating method, three conditions have to be met, namely, a strong interaction between the inorganic precursor and the organic templates; eliminating the formation of bulk manganese phosphate; and the preservation of the manganese phosphate framework without it collapsing upon template removal. Herein, a soft‐templating approach is reported using an organophosphonic acid (n‐hexylphosphonic acid) as both the etching and the templating agent, followed by high‐vacuum‐assisted annealing. This approach simultaneously satisfies the above conditions. Both microporous and mesoporous manganese phosphates with uniform pore sizes and well‐defined pore structures are obtained. The utilization of the organophosphonic acid is shown to be the key in the transformation from bulk manganese oxide into a highly ordered microporous phosphate. A very high surface area of 304.1 m2 g−1 is obtained for the microporous manganese phosphate, which is the highest among the reported values for Mn‐based compounds. The ultrafine micropores and high specific surface area of our manganese phosphate promote electrocatalytic activity for the oxygen evolution reaction.
Analysis of the Emergency Medicine Clinical Learning Environment
Authors: Ramana Feeser V. , Zemore Zachary , Appelbaum Nital , Santen Sally A. , Moll Joel , Aboff Brian , Hemphill Robin R.
Published: May 2019

Background

Residencies are grappling with ways to identify methods to internally monitor and improve their learning environments. Building on prior work, the objective of this study was to determine emergency medicine (EM) internal evaluations of perceived organizational support and psychological safety and compare to the results from the Accreditation Council for Graduate Medical Education (ACGME) Resident Survey for the purpose of program improvement and to explore factors affecting residents’ perception of their learning environment.

Methods

In 2017, the Virginia Commonwealth University School of Medicine Office of Graduate Medical Education and Office of Quality and Safety conducted an in‐person, anonymous safety survey of the residents across 19 residency programs on the Short Survey of Perceived Organizational Support (SPOS) and Psychological Safety Scale (PSS). These were compared to the ACGME Resident Survey for 19 programs. Resident interviews and open response evaluation data informed content analysis on program experiences.

Results

Institutional response rates were 63% for the internal learning environment survey and 96% for ACGME Resident Safety Survey. EM residents responded positively on the SPOS and PSS compared to other programs (ranked second highest scores on both scales). One‐hundred percent of respondents agreed or strongly agreed on SPOS items: “Help is available from my department when I have a problem.” “My department really cares about my well‐being.” “My department values my contribution to its well‐being.” Furthermore, EM had the highest overall training experience score (mean = 4.83) on the ACGME survey compared to the 18 other training programs. Qualitative responses suggest program strengths included supportive program leadership, positive working relationships with faculty, and emphasis on trainee wellness.

Conclusions

Compared to other programs, EM has created a positive environment of safety and support as perceived by their residents. Internal surveys of the learning environment can help programs understand their culture for purposes of improvement and align with the ACGME survey.
Multiproxy isotopic analyses of human skeletal material from Rapa Nui: Evaluating the evidence from carbonates, bulk collagen, and amino acids
Authors: Commendador Amy S. , Finney Bruce P. , Fuller Benjamin T. , Tromp Monica , Dudgeon John V.
Published: May 2019

Objectives

Stable isotope ratio analysis of bulk bone collagen dominates research into past diet; however, bone carbonate and compound specific isotope analyses (CSIA) of amino acids provide alternative, yet complementary, lines of evidence toward that same research goal. Together they inform on different aspects of diet, allowing greater certainty in reconstructions. Here we present new data on carbonate isotopes for Rapa Nui and reevaluate prehistoric diet in the context of these new and previously published bulk collagen and CSIA data.

Materials and methods

We analyzed carbon isotopes in bone carbonate from 28 prehistoric human teeth from Rapa Nui. These represent a subset of material examined previously for carbon and nitrogen isotope ratios in bulk collagen. We then reevaluate prehistoric diet in light of these and other published data. In addition, we analyzed carbon and nitrogen isotope ratios in 28 modern plant specimens from Rapa Nui to better approximate the isotopic value of the terrestrial endmember.

Results

Bulk data suggest a predominantly terrestrial diet, with the amount of marine sources incorporated varying though time. While previously argued to reveal greater amounts of marine consumption, reanalysis of recently published CSIA data suggests this result may relate to the proportion of carbon assimilated rather than consumed. Utilizing models incorporating concentration dependence for estimating dietary proportions results in much lower estimates of marine consumption, in line with findings of the bulk data.

Discussion

While these data indicate a larger focus on terrestrial resources, limitations in all forms of analysis make it difficult to determine exact dietary contributions in this mixed system. Better understanding of the complex physiological processes governing isotopic routing and fractionation, and knowledge of appropriate isotopic endmember values are needed to advance this research.
Highly Crystalline Mesoporous Phosphotungstic Acid: A High‐Performance Electrode Material for Energy‐Storage Applications
Authors: Ilbeygi Hamid , Kim In Young , Kim Min Gyu , Cha Wangsoo , Kumar Paskalis Sahaya Murphin , Park Dae‐Hwan , Vinu Ajayan
Published: May 2019

Heteropoly acids (HPAs) are unique materials with interesting properties, including high acidity and proton conductivity. However, their low specific surface area and high solubility in polar solvents make them unattractive for catalytic or energy applications. This obstacle can be overcome by creating nanoporosity within the HPA. We synthesized mesoporous phosphotungstic acid (mPTA) with a spherical morphology through the self‐assembly of phosphotungstic acid (PTA) with a polymeric surfactant as stabilized by KCl and hydrothermal treatment. The mPTA nanostructures had a surface area of 93 m2 g−1 and a pore size of 4 nm. Their high thermal stability (ca. 450 °C) and lack of solubility in ethylene carbonate/diethyl carbonate (EC/DEC) electrolyte are beneficial for lithium‐ion batteries (LIBs). Optimized mPTA showed a reversible capacity of 872 mAh g−1 at 0.1 A g−1 even after 100 cycles for LIBs, as attributed to a super‐reduced state of HPA and the storage of Li ions within the mesochannels of mPTA.
De Novo Synthesis of Highly Functionalized Benzimidazolones and Benzoxazolones through an Electrochemical Dehydrogenative Cyclization Cascade
Authors: Xu Fan , Long Hao , Song Jinshuai , Xu Hai‐Chao
Published: May 2019

Benzimidazolone and benzoxazolone moieties are important scaffolds in a variety of pharmaceutical molecules. These bicyclic heterocycles are usually prepared from a benzene derivative through the construction of an additional five‐membered heterocyclic ring. We report herein a method that enables the efficient synthesis of highly substituted benzimidazolone and benzoxazolone derivatives by building both the benzene and the heterocyclic rings through a dehydrogenative cyclization cascade. Readily available arylamine‐tethered 1,5‐enynes undergo a biscyclization/dehydrogenation cascade to afford functionalized benzanellated heterocycles in a single step with complete control of regioselectivity. These electricity‐powered oxidative transformations proceed with H2 evolution, thus obviating the need for transition‐metal‐based catalysts and oxidizing reagents.
Asymmetric Allylic Alkylation with Deconjugated Carbonyl Compounds: Direct Vinylogous Umpolung Strategy
Authors: Ran Guang‐Yao , Yang Xing‐Xing , Yue Jing‐Fei , Du Wei , Chen Ying‐Chun
Published: May 2019

An atom‐economic and highly efficient vinylogous umpolung strategy is developed for deconjugated carbonyl compounds, which generate electron‐deficient π‐allylpalladium complexes with Pd(OAc)2 under ligand‐free conditions. In cooperation with a chiral‐phosphonium‐based phase‐transfer catalyst, the asymmetric direct oxidative allylic alkylations of 3‐substituted oxindoles are furnished under O2 atmosphere. The γ‐ or even remote ϵ‐regioselective alkylation products, with substantial substituents, are delivered with excellent enantioselectivity, and can be further used to access diverse chiral spirocyclic architectures effectively. The Mukaiyama dienol silyl ether can be utilized similarly, indicating that the current active π‐allylpalladium species results from tautomerization of the PdII‐dienolate intermediate.
Reactions of Fe2(μ‐odt)(CO)6 (odt = 1, 3‐oxadithiolate) with small bite‐angle diphosphines to afford the monodentate, chelate, and bridge diiron complexes: Selective substitution, structures, protonation, and electrocatalytic proton reduction
Authors: Hu Meng‐Yuan , Yan Lin , Li Jian‐Rong , Wang Yan‐Hong , Zhao Pei‐Hua , Liu Xu‐Feng
Published: May 2019

Selective substitutions of Fe2(μ‐odt)(CO)6 (odt = 1,3‐oxadithiolate, A) and small bite‐angle diphosphines (Ph2P)2X [X = CH2 (dppm) or N (CH2CHMe2) (dppa)] have been well investigated in this study. With Me3NO·2H2O in MeCN at room temperature, the reaction of A and dppm produced the monodentate complex [Fe2(μ‐odt)(CO)5(κ1‐dppm)] (1), whereas the similar reaction with dppa afforded the chelate complex [Fe2(μ‐odt)(CO)4(κ2‐dppa)] (2). Using UV irradiation in toluene emitting at 365 nm, the treatment of A and dppm rarely resulted in the formation of the bridge complex [Fe2(μ‐odt)(CO)4(μ‐dppm)] (3), whereas the similar treatment with dppa formed the chelate complex 2. Under thermolysis condition, refluxing solution of A with dppm or dppa gave the bridge complex 3 and [Fe2(μ‐odt)(CO)4(μ‐dppa)] (4), respectively, in which the former was formed in toluene (110 °C) but the latter was produced in xylene (138 °C). All the new complexes 1–4 obtained above were characterized by element analysis, FT‐IR, NMR (1H, 31P) spectroscopies, and particularly for 1–3 by X‐ray crystallography. Furthermore, the in situ protonations of 2 with a weak acid HOAc (acetic acid) and a strong acid TFA (trifluoroacetic acid) are explored by means of FT‐IR and NMR (1H, 31P) spectra. In addition, the electrochemical behaviors of 2–4 are studied and compared through cyclic voltammetry (CV) in the absence and presence of a strong acid (TFA) as a proton source, indicating that they all are active for electrocatalytic proton reduction to hydrogen (H2).
1,3‐Diamino‐2‐propanol or 2‐aminoethanethiol modified active layer of thin‐film composite forward osmosis membrane
Authors: Sun Jiajin , Hu Xuhui , Huang Yangbo , Peng Ruichao , Luo Yunbai , Yu Ping
Published: May 2019

This work proposes three easy and effective methods to improve the density of the active layer of the thin‐film composite (TFC) forward osmosis (FO) membrane. Amino groups are introduced to the polyamide layer to react with the exposed acid chloride groups after a small molecule of 1,3‐diamino‐2‐propanol (DH) or 2‐aminoethanethiol (AE) or DH–AE being introduced. This may lead to a higher degree of crosslinking and form a more complex and networked aggregate structure. In this work, three modified membranes are successfully prepared, and a series of characterizations are carried out. The result is that all methods can improve the density of the active layer and increase the salt rejection without adversely affecting the selectivity. The hydrophilicity of the TFC‐DH film is significantly improved, the reverse salt flux of the TFC‐AE film is remarkably improved, and the effect of the TFC‐DH–AE film is between the TFC‐DH film and the TFC‐AE film. Therefore, the method of adding a small molecular material can increase the degree of polymerization. The method of introducing an inorganic element provides a valuable solution for designing and developing a novel and efficient FO film, which is simple and easy to be operated. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47923.
Preparation of Composite Filters Based on Porous Coordination Polymers by Using a Vacuum Filtration Method for Highly Efficient Removal of Particulate Matters
Authors: Gai Shuang , Fan Ruiqing , Xing Kai , Wang Ani , Zheng Xubin , Zhou Xuesong , Wang Ping , Yang Yulin
Published: May 2019

In this study, two novel crystal materials pcp1 and pcp1‐L have been synthesized successfully. The different conformations of the two crystals are mainly attributed to the introduction of the Schiff‐base ligand L (L=(E)‐4‐methyl‐N‐((6‐methoxypyridin‐2‐yl)methylene)aniline). Subsequently, pcp1 and pcp1‐L composites have been firstly produced by a vacuum filtration method on various substrates (i.e., melamine foam, plastic mesh, carbon fiber cloth and glass cloth). The obtained robust composites show excellent performance in removing PMs owing to high ζ potential, microporous structure, large conjugation system and electron cloud‐exposed metal center (DFT calculations) of pcp1 and pcp1‐L. Particularly, pcp1‐L@glass cloth with low pressure drop exhibits high thermal stability and high long‐term reproducibility. Additionally, the high removal efficiency of pcp1‐L@glass cloth towards particulate matters could also be maintained, even achieving >99.9 % in the car exhaust gas field test.
Determination of nikethamide by micellar electrokinetic chromatography
Authors: Purgat Krystian , Borowczyk Kamila , Zakrzewski Robert , Głowacki Rafał , Kubalczyk Paweł
Published: May 2019

A simple, fast, sensitive and reproducible micellar electrokinetic chromatography (MEKC)–UV method for the determination of nikethamide (NKD) in human urine and pharmaceutical formulation has been developed and validated. The method exhibits high trueness, good precision, short analysis time and low reagent consumption. NKD is an organic compound belonging to the psychoactive stimulants used as an analeptic drugs. The proposed analytical procedure consists of few steps: dilution of urine or drug in distilled water, centrifugation for 2 min (12,000g), separation by MEKC and ultraviolet‐absorbance detection of NKD at 260 nm. The background electrolyte used was 0.035 mol/L pH 9 borate buffer with the addition of 0.05 mol/L sodium dodecyl sulfate and 6.5% ACN. Effective separation was achieved within 5.5 min under a voltage of 21 kV (~90 μA) using a standard fused‐silica capillary (effective length 51 cm, 75 μm i.d.). The determined limit of detection for NKD in urine was 1 μmol/L (0.18 μg/mL). The calibration curve obtained for NKD in urine showed linearity in the range 4–280 μmol/L (0.71–49.90 μg/mL), with R2 0.9998. The RSD of the points of the calibration curve varied from 5.4 to 9.5%. The analytical procedure was successfully applied to analysis of pharmaceutical formulation and spiked urine samples from healthy volunteers.
Studies on oral bioavailability and first‐pass metabolism of withaferin A in rats using LC–MS/MS and Q‐TRAP
Authors: Dai Tianming , Jiang Weifan , Guo Zizheng , Wang Zhenyu , Huang Mingping , Zhong Guorui , Liang Chuxin , Pei Xuzhe , Dai Renke
Published: May 2019

Withaferin A (WA) is one of the major bioactive steroidal lactones with extensive pharmacological activities present in the plant Withania somnifera. The absolute oral bioavailability of WA remains unknown and human‐related in vitro data are not available. Therefore, in the present study, the absolute oral bioavailability of WA in male rats and the in vitro screening of absorption factors by Q‐trap and LC–MS/MS analysis were conducted to explore possible clinical properties of WA. The developed and validated analytical methods were successfully applied to the pharmacokinetic studies and in vitro measurement of WA. The oral bioavailability was determined to be 32.4 ± 4.8% based on intravenous (5 mg/kg) and oral (10 mg/kg) administrations of WA in male rats. The in vitro results showed that WA could be easily transported across Caco‐2 cells and WA did not show as a substrate for P‐glycoprotein. Moreover, the stability of WA was similar between male rat and human in simulated gastric fluid (stable), in intestinal microflora solution (slow decrease) and in liver microsomes (rapid depletion, with a half‐life of 5.6 min). As such, the first‐pass metabolism of WA was further verified by rat intestine‐liver in situ perfusion, revealing that WA rapidly decreased and 27.1% remained within 1 h, while the content of three major metabolites (M1, M4, M5) identified by Q‐trap increased. This perfusion result is consistent with the oral bioavailability results in vivo. The first‐pass metabolism of WA might be the main barrier in achieving good oral bioavailability in male rats and it is predicted to be similar in humans. This study may hold clinical significance.
An efficient high‐speed countercurrent chromatography method for preparative separation of javanicin from Fusarium solani, a fungus isolated from the fruiting body of the mushroom Trametes trogii
Authors: Guo Ruyi , Cai Xu , Li Qian , Huang Yun , Chen Benke , Guan Ping , Tang Jintian , Zou Xianwei
Published: May 2019

To develop an efficient method for large preparation of javanicin from Fusarium solani, a rapid and simple method by high‐speed countercurrent chromatography was established based on average polarity (P′ values) and partition coefficients (K values) of crude samples. A suitable solvent system for high‐speed countercurrent chromatography was selected from many possible biphasic solvent systems. HSCCC was successfully applied to separate and purify javanicin, the main bioactive component of solid cultures of the fungus F. solani isolated from the fruiting body of Trametes trogii, with petroleum ether–ethyl acetate–methanol–water (4:3:2:1, v/v) as solvent system. A total amount of 40.6 mg of javanicin was obtained from 100 mg crude sample. The purity of javanicin was 92.2% with a recovery of 95.1%, as determined by high‐performance liquid chromatrography. The molecular structure was identified primarily by NMR and MS methods. The results indicated that high‐speed countercurrent chromatography could be a powerful technology for separating naphthoquinones from the solid cultures of the fungus F. solani. It is also of significance that the separation of javanicin from natural source was carried out for the first time utilizing high‐speed countercurrent chromatography.
Direct costs of both inpatient and outpatient care for all type cancers: The evidence from Beijing, China
Authors: Yin Xuejun , Xu Yue , Man Xiaowei , Liu Liming , Jiang Yan , Zhao Liying , Cheng Wei
Published: May 2019

Background

Cancer is a major public health issue worldwide. The cost of cancer care imposes a substantial economic burden on society and patient, but it has not been thoroughly studied in China. This study aimed to describe direct cost and cost elements of all cancer types by different beneficial characteristics.

Methods

The research was a retrospective observational study based on inpatient and outpatient records with a primary diagnosis of cancer from 31 hospitals in 2016. Total cost and cost per time were analyzed by cancer type, sources (prescription medicines, consumables fee for diagnosis and surgery, and other health services), and beneficial characteristics (gender and age).

Results

A total of 30 224 eligible inpatient admissions and 485 391 outpatient visits were identified during the study period. Inpatient care costs account for 58.6% cancer treatment costs. Nearly 70% of the total expenditure is spent on patients aged 50‐79 years. Lung cancer had the highest economic cost (15% of overall cancer costs), followed by breast cancer (12%), and colorectal cancer (10%). Anticancer drug cost accounted a large proportion in both inpatient (37.7%) and outpatient care (64.6%). The average cost per inpatient admission was estimated to be $4590.1 (5621.9), ranging from $1157.7 (1349.8) for testis cancer to $7975 (7343.9) for stomach cancer. The regression analyses revealed that length of hospital stay, cancer type, age, payment type, and hospital level were highly correlated with the expenditure per admission (P < 0.001).

Conclusions

The cancer care cost is substantial and varies with cancer type. Our findings provide important information for health service planning, allowing more efficient allocation of health resources for the care of people with cancer.