bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessing the variation in workload among general practitioners in urban and rural areas: An analysis based on SMS time sampling data
Authors: van Hassel Daniël , Verheij Robert , Batenburg Ronald
Published: September 2018

Objective

An important reason why general practitioners (GPs) are less inclined to work in rural areas is a perception of a higher workload. This study assesses the differences in the workloads of GPs in rural and urban areas. We used two definitions of rurality, one based on the number of addresses per square kilometre, and a second defined by the expected decline in population.

Methods

We collected time use data over 1 year by sending SMS text messages to Dutch GPs who each participated during a period of 1 week. This data was matched with those from GPs' registration and practice location. Data from 596 self‐employed GPs were analysed using descriptive statistics and multiple regression analyses.

Results

In group practices, the patient list size of rural GPs was, on average, 231 patients more than those of urban GPs. They worked 3.5 more hours per week, with 2.6 more hours directly related to patients. A small significant relation was found between degree of urbanisation and the dependent variables list size and working hours. Working in a depopulation area had no significant effect on the workload indicators. Furthermore, GPs in group practices worked significantly fewer hours, and had smaller list sizes, than GPs in single‐handed practices.

Conclusion

The results show that the assumption of a higher workload in rural practices does not completely match the objective workload of GPs in these areas. Rural GPs have a higher workload in certain cases, but the type of a practice seems a more important determinant.
Inequality trends in the demographic and geographic distribution of health care professionals in China: Data from 2002 to 2016
Authors: Wu Jingxian , Yang Yongmei
Published: September 2018

China has long been negatively affected by a shortage and maldistribution of health workers. This study aimed to examine the national and regional trends in the demographic and geographic distribution inequality of health care professionals in China from 2002 to 2016. Based on data from the China Health and Family Planning Statistical and China Statistical Yearbooks, we calculated the Gini coefficient and the Theil T and Theil L indices based on the number of health care professionals per capita and per geographic area to measure the inequalities in their demographic and geographic distribution, respectively. The contributions by intra‐regional and inter‐regional differences on total inequality were explored within and among East, Central, and West China via Theil index decomposition. We found that the national demographic distribution of health care professionals maintained in an absolute equality level, and the inequality indices decreased gradually, whereas the corresponding geographic inequalities were severe and presented a worsening trend. Compared with nurses, physicians not only maintained higher densities but also maintained a more equal distribution. Intra‐regional disparities within the east, central, and western regions were the main cause for overall demographic inequality, whereas both intra‐regional and inter‐regional disparities significantly contributed to overall geographic inequality. To conclude, the distribution equality of health care professionals by population was satisfactory, whereas the corresponding distribution inequality by area was severe. Different types of distribution inequality of health care professionals existed regionally and nationally despite their increasing quantities and densities. Factors beyond population size should be considered when the government introduces health workforce allocation policies.
Prioritizing countermeasures for reducing seawater‐intrusion area by considering regional characteristics using SEAWAT and a multicriteria decision‐making method
Authors: Kim Il Hwan , Yang Jeong‐Seok
Published: September 2018

Coastal areas are being increasingly damaged by the expansion of seawater‐intrusion areas. This study suggested a three‐step method to prioritize the countermeasures adopted to reduce the areas affected by seawater intrusion. First, the most vulnerable area to damage from seawater intrusion was selected among 25 areas on the western coast of the Republic of Korea using three multicriteria decision‐making (MCDM) methods. As a result, Taean‐gun was selected as the most vulnerable area for seawater intrusion. Second, a numerical model called SEAWAT was configured to predict the areas where seawater intrusion could potentially occur. For future scenarios, Representative Concentration Pathways (RCPs) 4.5 and 8.5 were used as the sea‐level rise scenarios. To predict the future use of groundwater, the future groundwater extraction rate was predicted using a linear regression of the groundwater‐use data over the past 10 years. As a result, it was predicted that 68.5% of the total Taean‐gun area would be affected by seawater intrusion for RCP 8.5 and current trends in groundwater use. Third, the effectiveness of the measures adopted for the reduction of seawater‐intrusion areas were analysed by considering the projected future scenario and the local characteristics (including the total population, population density, groundwater‐level distribution, salinity distribution, groundwater‐use characteristics, and ground‐elevation distribution) of the Taean‐gun district. After considering the effects of the countermeasures adopted for the different locations in Taean‐gun and the data related to seawater intrusion, the priority areas for applying countermeasures against seawater intrusion were determined using three MCDM methods. It was concluded that the Taean‐myeon is a priority area for applying countermeasures.
The two‐sample linear regression model with interval‐censored covariates
Authors: Pacini David
Published: September 2018

There are surveys that gather precise information on an outcome of interest, but measure continuous covariates by a discrete number of intervals, in which case the covariates are interval censored. For applications with a second independent dataset precisely measuring the covariates, but not the outcome, this paper introduces a semiparametrically efficient estimator for the coefficients in a linear regression model. The second sample serves to establish point identification. An empirical application investigating the relationship between income and body mass index illustrates the use of the estimator.
RAQET: Large‐scale two‐component relativistic quantum chemistry program package
Authors: Hayami Masao , Seino Junji , Nakajima Yuya , Nakano Masahiko , Ikabata Yasuhiro , Yoshikawa Takeshi , Oyama Takuro , Hiraga Kenta , Hirata So , Nakai Hiromi
Published: September 2018

The Relativistic And Quantum Electronic Theory (RAQET) program is a new software package, which is designed for large‐scale two‐component relativistic quantum chemical (QC) calculations. The package includes several efficient schemes and algorithms for calculations involving large molecules which contain heavy elements in accurate relativistic formalisms. These calculations can be carried out in terms of the two‐component relativistic Hamiltonian, wavefunction theory, density functional theory, core potential scheme, and evaluation of electron repulsion integrals. Furthermore, several techniques, which have frequently been used in non‐relativistic QC calculations, have been customized for relativistic calculations. This article introduces the brief theories and capabilities of RAQET with several calculation examples. © 2018 The Authors Journal of Computational Chemistry Published by Wiley Periodicals, Inc.
Prion protein conversion triggered by acidic condition: a molecular dynamics study through different force fields
Authors: Thompson Helen Nathalia , Thompson Claudia Elizabeth , Andrade Caceres Rafael , Dardenne Laurent Emmanuel , Netz Paulo Augusto , Stassen Hubert
Published: September 2018

Prions are proteins that cause a group of invariably fatal neurodegenerative diseases, one of the most known being bovine spongiform encephalopathy. The three‐dimensional structure of PrPSc, the altered isoform of the prion protein, has not been fully elucidated yet, and studies on prion conversion mechanisms must rely on hypothetical β‐rich structures. Experimental and computational studies indicate that the use of low pH is capable to produce a gain of β‐structure content in the otherwise unstructured N‐terminal region. These in silico studies have used different PrP fragments from distinct organisms, and with different lengths and simulation protocols, making it difficult to identify the influence of the force fields on the formation of such structures. Here, we performed a systematic study of the influence of six well‐established force fields (GROMOS96 53a6, GROMOS96 43a1, AMBER99SB, AMBER99SB‐ILDN, CHARMM27, and OPLS‐AA/L) on the process of structural conversion of the Syrian hamster cellular prion protein simulated at acidic and neutral pH. From our analysis, we observe a strong dependence of the results with the different force fields employed. Additionally, only GROMOS96 53A6 and AMBER99SB force fields are capable to capture a high β‐sheet formation at acidic pH and adequately reproduce the neutral pH. In both cases, the β‐sheet elongation seems to be guided by the movement of the N‐terminal tail toward the N‐terminal of α‐helix HB under acidic condition. These results comprise the most wide‐ranging study to date correlating force fields to structural changes in the cellular prion protein. © 2018 Wiley Periodicals, Inc.
Methods for the Simulation of the Slowing of Low‐Energy Electrons in Water
Authors: Smith Marisa E. , Green N. J. B. , Pimblott S. M.
Published: September 2018

A computational Monte Carlo simulation approach for modeling the thermalization of low‐energy electrons is presented. The simulation methods rely on, and use, experimentally based cross sections for elastic and inelastic collisions. To demonstrate the different simulation options, average numbers of interactions and the range of low‐energy electrons with initial energies ranging from 1 to 20 eV are calculated for density normalized gaseous water. Experimental gas‐phase cross sections for (subexcitation) electrons of energies in the range of 1–20 eV were taken from the compilation of Hayashi. The ballistic collision‐by‐collision simulations provide information on the intricacies of the thermalization processes not available experimentally. © 2018 Wiley Periodicals, Inc.
Mechanistic insights into N‐Bromosuccinimide‐promoted synthesis of imidazo[1,2‐a]pyridine in water: Reactivity mediated by substrates and solvent
Authors: Qian Min , Qin Bowen , Yuan Haiyan , Li Wenliang , Zhang Jingping
Published: September 2018

The mechanism of N‐Bromosuccinimide (NBS) promoted synthesis of imidazo[1,2‐a]pyridine in water as well as the effective activation modes of NBS was investigated by Density Functional Theory (DFT) calculations. Two main mechanisms that differ in the reaction sequence of substrate were explored: styrene with NBS then followed by 2‐aminopyridine (M1) or simultaneously with NBS and 2‐aminopyridine (M2), and water‐assisted M2 is the more favored one. We found that the adding sequence of 2‐aminopyridine affects profoundly on the title reaction. Moreover, upon the assistance of water and NBS, the preferential mechanistic scenario involves three major processes: nucleophilic addition, stepwise H‐shift and intramolecular cyclization, three‐step deprotonation, rather than a classical bromonium ion species. Specifically, the cooperative interaction of NBS and water plays a critical role in the title reaction. Water acts as solvent, reactant, anchoring, stabilizer, and catalyst. NBS promotes the above three processes by the effective forms of Br+/Br−, succinimide, and its ethanol isomer. Furthermore, noncovalent interactions between catalysts and substrates are responsible for the different reactive activities of M1 and M2. Our results indicate that simultaneous adding of all reactants is recommended toward economical synthesis. © 2018 Wiley Periodicals, Inc.
“We make a direct impact on people's lives”: Youth empowerment in the context of a youth‐led participatory budgeting project
Authors: Augsberger Astraea , Gecker Whitney , Collins Mary Elizabeth
Published: September 2018

Participatory budgeting [PB] is a democratic process whereby community members determine how to spend governmental funds. Youth‐led PB is relatively new, occurring in select U.S. cities. During youth‐led PB, youth collect ideas, develop proposals, and advertise community improvement projects for which they, citywide, cast deciding votes. The study examined opportunities for the empowerment youth at each stage of a youth‐led PB project. Data collection included individual interviews with 31 youths and adult stakeholders, 3 focus groups with youths, and 7 observations of meetings. The data were analyzed using consensual qualitative research methods. Findings align well with the psychological empowerment literature and demonstrate several opportunities for empowerment throughout the PB project, including feeling in charge of the process, understanding and allocating resources, and influencing positive community change. Findings also demonstrate potential barriers to empowerment, including understanding bureaucratic decision making, and influencing policy. PB is relevant to furthering our understanding of the empowerment of youth. The youths who participated in the present study expressed feelings of competence, purpose, and an ability to use the skills learned to engage fellow youths in the PB process. Additional empirical research is needed to examine the dimensions of empowerment at each stage of the PB process.
The configuration of DMD and the maximum intensity projection method for improving contrast in DMD‐based confocal microscope
Authors: Chang Min , Zhang Zhiqiang , Zhang Xuedian , He Menghui , Qiu Zhijie , Xu Jian
Published: September 2018

In this article, an operation strategy of digital micromirror device (DMD) and the maximum intensity projection (MIP) image processing method are proposed to improve the contrast of images in confocal microscopy. First, the configuration of DMD is demonstrated and the effect of scanning unit size on image performance is analyzed. Then, the image processing method MIP is applied. According to the MIP method, only the maximum intensity projection point of the same pixel is chosen from every image, and the maximum intensity projection point exactly corresponds to the positon where mirror is at “on” position during the scanning process in DMD‐based confocal microscope system,. Thus, high contrast of images can be achieved by using MIP. Finally, experiments are conducted to verify imaging performance by changing the parameter of scanning unit size and applying a MIP image processing technique. The results show that DMD scanning unit size and MIP image processing techniques play important roles in improving image contrast. Smaller scanning unit size of DMD improves axial contrast but greatly decreases the signal to noise ratio, which thus leads to reduced image contrast. Larger scanning unit size produces a better signal to noise ratio, thus better image contrast. However, a large S will sacrifice the processing time. Therefore, DMD scanning unit size should be smaller on the premise that image contrast can be satisfied.

Research Highlights

Effect of DMD scanning unit size setting on image contrast is analyzed and verified.

The maximum intensity projection (MIP) is investigated to improve the image contrast.

Experiments are conducted to verify the enhancement of the image contrast.
Microstructure characteristics and mechanical properties of Meretrix lusoria shell
Authors: Zhao Qian , Lin Zhaohua , Liang Yunhong , Liu Chunbao , Zhang Zhihui , Yu Zhenglei , Ren Luquan
Published: September 2018

The microstructure and mechanical properties of Meretrix lusoria shell were investigated. M. lusoria shell was comprised of three layers (outer layer, middle layer and inner layer). Outer layer with serried mastoid structure enhanced the connection strength with middle layer. The middle layer consisted of blocky pattern structure with porosity and crossed‐lamellar structure. The inner layer exhibited the typical crossed‐lamellar structure. Combined with structure characteristic, phase of aragonite confirmed the crossed‐lamellar structure further, building material base for mechanical properties including flexure strength (296.26 MPa), compression strength (6.71 MPa) and crack arrest ability. Microstructure of the shell was the function base of crack deflection phenomenon, which dispersed and defused the applied load via the change of crack extension direction. The investigation of M. lusoria shell provided bionic models for the design and fabrication of bioinspired composites in engineering fields.

Research Highlights

Microstructure and mechanical properties of Meretrix lusoria shell were investigated.

Crossed‐lamellar structure was the microstructure characterization.

M. lusoria shell owned high flexure strength and crack arrest property.
Synthesis of Novel Anti‐inflammatory Psoralen Derivatives ‐ Structures with Distinct Anti‐Inflammatory Activities
Authors: Timonen Juri M. , Vuolteenaho Katriina , Leppänen Tiina , Nieminen Riina M. , Aulaskari Paula , Jänis Janne , Vainiotalo Pirjo , Moilanen Eeva
Published: September 2018

As a continuum to our work with coumarins, 12 psoralens were synthesized and evaluated for their anti‐inflammatory activity. Psoralens were prepared in three steps; at first, 7‐hydroxycoumarins were synthesized by von Pechmann condensation and then converted to 7‐(2‐oxopropoxy)coumarins. In the final step, a fused furan ring was introduced in an intramolecular ring‐formation reaction. Based on a SciFinder search, two out of the 12 synthesized psoralen derivatives (compounds 9 and 12) were found to be novel. The derivatives displayed anti‐inflammatory activity by suppressing iNOS and IL‐6 expression, but their mechanism of action seemed to be dependent on the substitution. Compound 6 with propyl side chain inhibited NF‐κB mediated transcription, while compound 10 with a phenyl substituent down‐regulated iNOS expression in a posttranscriptional manner. The results introduce psoralen derivatives as promising anti‐inflammatory compounds with potential for treatment of conditions involving iNOS and/or IL‐6‐mediated adverse responses.
Comparison of actinomycin peptide synthetase formation in Streptomyces chrysomallus and Streptomyces antibioticus
Authors: Crnovčić Ivana , Lang Manuel , Ortel Ingo , Süssmuth Roderich D. , Keller Ullrich
Published: September 2018

Actinomycin peptide synthetase genes constitute two oppositely oriented transcriptional units, acmADR, and acmBC, separated by a non‐coding intergenic region. Gene constructs of the intergenic region together with its adjoining gene acmA or acmB from the actinomycin biosynthetic gene cluster of Streptomyces chrysomallus were transferred into Streptomyces lividans TK64. Each construct expressed the respective synthetase indicating divergent promoters. Primer extension revealed for both directions −10 and −35 boxes similar to σ70‐dependent promoters from Streptomyces and E. coli. No conspicuous regulatory sequences were detected. Accordingly, S. chrysomallus—grown in glucose‐containing medium—produced the peptide synthetases AcmA and AcmB/C as well as actinomycin during logarithmic growth phase. Alignments with the corresponding intergenic region of the actinomycin biosynthetic gene cluster in Streptomyces antibioticus identified analogous −10 and −35 boxes of σ70 consensus sequence. However, in S. antibioticus—cultivated in the same conditions—AcmA and AcmB/C were at maximum activity in late log phase and actinomycin formation peaked in stationary phase. The different patterns of formation of actinomycin and its peptide synthetases encoded by the highly homologous actinomycin biosynthetic gene clusters in S. chrysomallus and S. antibioticus suggest strain‐specific control of biosynthesis in agreement with absence of pathway‐specific regulatory genes.
Facile synthesis of titanium(IV) ion‐immobilized poly‐glycidyl methacrylate microparticles functionalized with polyethylenimine and adenosine triphosphate for highly specific enrichment of intact phosphoproteins
Authors: Wang Hao , Tian Zhixin
Published: September 2018

In this study, a facile synthesis of the titanium(IV) ion‐immobilized poly‐glycidyl methacrylate microparticles functionalized with polyethylenimine and adenosine triphosphate was developed for efficient enrichment of intact phosphoproteins. The titanium(IV) ion‐immobilized microparticles had higher saturated adsorption capacity for phosphoproteins (1217.6 mg/g for β‐casein) than nonphosphoproteins (97.1 mg/g for bovine serum albumin) and the average particle diameter was about 1.4 μm with good dispersibility. In application, as demonstrated by SDS‐PAGE, titanium(IV) ion‐immobilized microparticles exhibited good performance in enriching intact phosphoproteins from standard protein mixtures of β‐casein and bovine serum albumin with high specificity and selectivity. In addition, titanium(IV) ion‐immobilized microparticles were also successfully applied in intact phosphoprotein enrichment from complex biological samples including nonfat milk, chicken egg white, and mouse heart tissue extract.
Coupling of CE‐MS for protein and peptide analysis
Authors: Mikšík Ivan
Published: September 2018

The review is focused on the latest developments in the analysis of proteins and peptides by capillary electrophoresis techniques coupled to mass spectrometry. First, the methodology and instrumentation are overviewed. In this section, recent progress in capillary electrophoresis with mass spectrometry interfaces and capillary electrophoresis with matrix‐assisted laser desorption/ionization is mentioned, as well as separation tasks. The second part is devoted to applications—mainly bottom‐up and top‐down proteomics. It is obvious that capillary electrophoresis with mass spectrometry methods are well suited for peptide and protein analysis (proteomic research) and it is described how these techniques are complementary and not competitive with the often used liquid chromatography with mass spectrometry methods.
Stratifying Minimal Versus Severe Pain in Knee Osteoarthritis Using a Musculoskeletal Ultrasound Protocol
Authors: Bernardo‐Bueno Mary Monica , Gonzalez‐Suarez Consuelo B. , Malvar Andrea Kristina , Cua Ronald , Feliciano Daniel , Tan‐Sales Bee Giok , Aycardo Svetlana Maris O. , Tan‐Ong Millicent , Chan Robert , De Los Reyes Francisco
Published: September 2018

Objective

The aim of this cross‐sectional correlational study was to determine the association of pain with morphologic and inflammatory sonographic findings in patients with knee osteoarthritis.

Methods

A total of 113 participants with knee osteoarthritis were assessed using visual analog scale pain score and sonography. Ultrasound evaluation included morphologic changes (ie, articular cartilage degeneration, medial and lateral meniscal protrusion, and presence of osteophytes on the joint margins) and inflammatory changes (ie suprapatellar effusion and/or synovitis, Baker cyst, superficial and deep infrapatellar effusion, pes anserine tendinopathy, and Hoffa panniculitis).

Results

Cluster analysis via Ward's method grouped patients with minimal pain (visual analog scale score, 0–4) and with substantial pain (visual analog scale score, 5–10). Stepwise logistic regression yielded 5 variables that significantly explained the variation in the probability of perceived substantial pain at 10% level of significance: lateral cartilage clarity (LCC; P = .025), medial cartilage clarity (MCC; P = .20), medial cartilage thickness (MCT; P = .041), medial meniscus protrusion (MMP) (P = .029), and osteophytes at medial femoral margin (P = .082), with 63% overall prediction accuracy. When age and sex were added, 4 variables remained significant at a 10% level of significance: LCC, MCC, MCT, and MMP, with 65% overall prediction accuracy. The receiver operating characteristic curve of this model was 0.667.

Conclusion

The study was able to demonstrate that morphologic abnormalities in the ultrasound parameters for LCC, MCC, MCT, and MMP were able to predict significant joint pain in knee osteoarthritis. There were no inflammatory changes that contributed to significant joint pain in this study.
Association of moose parturition and post‐parturition habitat with calf survival
Authors: Severud William J. , DelGiudice Glenn D. , Obermoller Tyler R.
Published: September 2018

Habitat use during calving and the energetically demanding post‐parturition period can be an important determinant of neonatal survival. The moose (Alces alces) population in northeastern Minnesota, USA declined 65% from 2006 to 2018. During 2013–2015, annual survival of calves was estimated as low as 28%. We remotely monitored global positioning system (GPS)‐collared adult female moose and their neonates during the calving and post‐parturition seasons to examine calving movements, birth‐sites, habitat use, survival, and cause‐specific mortality of neonates. Identifying the association of specific landscape characteristics with neonate survival should yield insight into mechanisms contributing to the declining moose population and serve as a basis for an ecologically sound management response. We compared habitat characteristics of pre‐calving, calving, peak‐lactation, and mortality sites at a fine and broad scale. We also compared calving sites of females that successfully reared a calf to winter to those that did not. In general, females tended to move to areas of more conifer cover to calve. During peak‐lactation, females and their calves used steeper areas with abundant forage and high concealment but less conifer cover. Mortalities occurred at sites that were more level than other site types. Females that successfully reared a calf to 1 February typically calved in areas with more deciduous forest and less forested wetland cover than females whose calves died before 9 months of age. Habitat improvement projects for moose should consider forage requirements and placement on the landscape in relation to cover and slope. © 2018 The Wildlife Society.
Sensitivity of Antibacterial Activity to Backbone Sequence in Constitutionally Isomeric OligoTEAs
Authors: Hoff Emily A. , Artim Christine M. , Brown Joseph S. , Alabi Christopher A.
Published: September 2018

Antimicrobial peptides are promising alternatives to traditional antibiotics but their translational potential is limited due to rapid degradation by serum proteases. Recently, a number of peptidomimetics with backbones resistant to proteolysis have been synthesized and their antimicrobial potential evaluated as a function of their hydrophobic to cationic ratio. However, these mimetics also have a fixed backbone thus making it difficult to isolate the effect of backbone hydrophobic composition and sequence. In this work, advantage is taken of the oligothioetheramide (oligoTEA) synthetic strategy that allows for precise control over backbone and pendant group placement to systematically study the effect of backbone hydrophobic sequence while keeping pendant group constant. Biophysical data acquired with a set of constitutional oligoTEA isomers show that backbone hydrophobic sequence, that is, local hydrophobicity, affects the mode of oligoTEA interaction with lipid bilayers. This differential interaction among the constitutionally isomeric oligoTEAs is manifested in their antibacterial activities and points to the possibility of using backbone hydrophobic sequence to tune antibacterial potency and selectivity.
High‐Performance Polybenzoxazine Derived from Polyfunctional Benzoxazine Composed of an Oligonuclear Phenolic Compound Having a 4,4′‐Dimethylenebiphenyl Linker
Authors: Kawauchi Takehiro , Osawa Tsubasa , Matsumura Shunichiro , Mori Takuto , Furukawa Nobuyuki , Ishikawa Kazunori , Iwasaki Koju , Takeichi Tsutomu
Published: September 2018

A novel polyfunctional benzoxazine monomer, OP‐a, is synthesized from aniline, formaldehyde, and an oligonuclear phenolic compound (OP) with a 4,4′‐dimethylenebiphenyl group as the phenol linker. After thermal curing of OP‐a up to 240 °C, a brown‐colored, transparent polybenzoxazine (POP‐a) film is obtained. The mechanical and thermal properties of the POP‐a film are investigated by tensile test, dynamic mechanical analysis (DMA), and thermogravimetric analysis (TGA). The POP‐a film is extremely tough compared with a typical polybenzoxazine (PB‐a) film. The elongation at break of the POP‐a film is 7.6%, which is surprisingly large for the highly cross‐linked thermoset. The high cross‐link density is suggested from the very high storage modulus (over 1 GPa) above the glass transition temperature (T
g) observed by DMA. The T
g of POP‐a is also improved significantly to T
g = 223 °C, which is approximately 50 °C higher than that of PB‐a. Moreover, TGA reveals that the thermal stability of POP‐a is also enhanced.
Solution Processed Coating of Polyolefin on Melamine Foams to Fabricate Tough Oil Superabsorbents
Authors: Ren Qiang , Dai Tian , Jin Xuanyi , Wu Dun , Wang Chenyi , Li Jian , Zhu Shiping
Published: September 2018

Oil superabsorbent porous materials having rapid oil/water separation, high oil absorption capacity, good mechanical strength, superior recyclability, low costs, and manufacture scalability are still highly desired for oil spill cleanup applications. In this work, commercially available melamine foams are modified through dip‐coating by polyolefin/toluene solution. All characterizations confirm that polyolefin is successfully coated on surfaces of the melamine foam skeleton, giving a micro‐nano scale hierarchical architecture. The modified foams absorb oil and repel water with a water contact angle higher than 130°. The absorption capacities of the modified foams for various oil and solvents are in the range of 42.6–116.5 g g−1. The retention of sorption capacity remains above 95% after 100 cycles of sorption–squeezing. Mechanical testing reveals that the compressive‐recovery property is kept and the tensile strains at break of the modified foams are improved compared to their original counterparts. This method is facile, inexpensive, and can be easily scaled‐up.
Cox rings and algebraic maps
Authors: Mańdziuk Tomasz
Published: September 2018

Given a morphism from a Mori Dream Space X to a smooth Mori Dream Space Y and quasicoherent sheaves on X and on Y, we describe the inverse image of by F and the direct image of by F in terms of the corresponding modules over the Cox rings graded in the class groups.
Polymer Synthesis with More Than One Form of Living Polymerization Method
Authors: Guo Xiaofeng , Choi Bonnie , Feng Anchao , Thang San H.
Published: September 2018

Controlled radical polymerization (CRP) or controlled/living radical polymerization has revolutionized the polymer industry as a tool for the preparation of a wide variety of polymers. This process enables the preparation of polymers with good control of molecular weight, narrow polydispersity, and a range of architectures including block and graft copolymers, star polymers, and other functional polymers. The mechanistic transformation reaction provides a great opportunity to tune chemical and physical properties of copolymers. It can be applied to combine different homopolymers using post‐modification techniques or by the use of a dual initiator, allowing the combination of mechanistically distinct polymerization reactions. This review will cover CRP transformations including the synthesis of block copolymers with both linear structures (AB, ABA, (AB)
n
, multiblocks, etc.) and branched macromolecular architectures (graft, miktoarm star, and dendritic‐like), which are obtained by a combination of more than one form of living polymerization reaction.
Effects of temperature on bacterial microbiome composition in Ixodes scapularis ticks
Authors: Thapa Santosh , Zhang Yan , Allen Michael S.
Published: September 2018

Ixodes scapularis, the blacklegged deer tick, is the principal vector of Lyme disease in North America. Environmental factors are known to influence regional and seasonal incidence of Lyme disease and possibly the endemicity of the disease to the northeastern and upper mid‐western regions of the United States. With a goal to understand the impact of environmental temperature on microbial communities within the tick, we investigated the bacterial microbiome of colony‐reared I. scapularis ticks statically incubated at different temperatures (4, 20, 30, and 37°C) at a constant humidity in a controlled laboratory setting by comparison of sequenced amplicons of the bacterial 16S V4 rRNA gene to that of the untreated baseline controls. The microbiomes of colony‐reared I. scapularis males were distinct than that of females, which were entirely dominated by Rickettsia. In silico removal of Rickettsia sequences from female data revealed the underlying bacterial community, which is consistent in complexity with those seen among male ticks. The bacterial community composition of these ticks changes upon incubation at 30°C for a week and 37°C for more than 5 days. Moreover, the male ticks incubated at 30 and 37°C exhibited significantly different bacterial diversity compared to the initial baseline microbiome, and the change in bacterial diversity was dependent upon duration of exposure. Rickettsia‐free data revealed a significantly different bacterial diversity in female ticks incubated at 37°C compared to that of 4 and 20°C treatments. These results provide experimental evidence that environmental temperature can impact the tick bacterial microbiome in a laboratory setting.
Partial inverse problems for the Sturm‐Liouville equation with deviating argument
Authors: Bondarenko Natalia P. , Yurko Vjacheslav A.
Published: September 2018

Several partial inverse problems for the Sturm‐Liouville equation with a constant delay are studied. We suppose that the potential is known a priori on an interior part of the interval and recover the potential on the remaining subintervals from fractional parts of two spectra. Uniqueness theorems are proved, and a constructive procedure is provided for the solution of the considered inverse problems.
Asymmetric cell division with stochastic growth rate. Dedicated to the memory of the late Spartak Agamirzayev
Authors: Efendiev Messoud , van Brunt Bruce , Zaidi Ali A. , Shah Touqeer H.
Published: September 2018

A cell growth model for a size‐structured cell population with a stochastic growth rate for size and division into two daughter cells of unequal size is studied in this paper. The model entails an initial boundary value problem that involves a second‐order parabolic partial differential equation with two nonlocal terms, the presence of which is a consequence of asymmetry in the cell division. The solution techniques for solving such problems are rare due to the nonlocal terms. In this paper, we solve the initial boundary value problem for arbitrary initial distributions. We obtain a separable solution, as well as the general solution to the partial differential equation, and show that the solutions converge to the separable solution for large time. As in the symmetric division case, the dispersion term does not affect the rate of convergence to the separable solution.
Structure equations and constraint manifolds on Lorentz plane
Authors: Durmaz Olgun , Aktaş Buşra , Gündoğan Halit
Published: September 2018

Calculating the structure equation of a chain is important to represent the position of the end link on the chain. Furthermore, the structure equation helps to determine the constraint manifold of the chain. The constraint manifold satisfies to make geometric interpretations about the form that is obtained. What is more, the constraint forced on the positions of the end link by the rest of the chain is represented by the manifold. In Lorentz space, the structure equations change according to the causal characters of the first link. In this paper, we attain the structure equations of a planar open chain in terms of the causal character of the first link in this space. Later, the constraint manifolds of the chain by using these equations are given. Some geometric comments about these manifolds are explained.
The accuracy of an HDG method for conservative fractional diffusion equations
Authors: Karaaslan Mehmet Fatih
Published: September 2018

In this paper, we introduce and investigate the performance of a hybridizable discontinuous Galerkin (HDG) method for approximating the solution of conservative fractional diffusion equations (CFDE). The main attractive feature of these methods is the fact that the only globally coupled unknowns are those at the element boundaries. We first introduce the HDG method for the CFDE and prove the existence and uniqueness of the numerical solution provided that the stabilization parameter is strictly positive. We provide extensive numerical results to test the convergence behavior of the HDG approximation.
CT sinogram‐consistency learning for metal‐induced beam hardening correction
Authors: Park Hyoung Suk , Lee Sung Min , Kim Hwa Pyung , Seo Jin Keun , Chung Yong Eun
Published: September 2018

Purpose

This paper proposes a sinogram‐consistency learning method to deal with beam hardening‐related artifacts in polychromatic computerized tomography (CT). The presence of highly attenuating materials in the scan field causes an inconsistent sinogram that does not match the range space of the Radon transform. When the mismatched data are entered into the range space during CT reconstruction, streaking and shading artifacts are generated owing to the inherent nature of the inverse Radon transform

Methods

The proposed learning method aims to repair inconsistent sinogram by removing the primary metal‐induced beam hardening factors along the metal trace in the sinogram. Taking account of the fundamental difficulty in obtaining sufficient training data in a medical environment, the learning method is designed to use simulated training data and a patient’s implant type‐specific learning model is used to simplify the learning process.

Results

The feasibility of the proposed method is investigated using a dataset, consisting of real CT scans of pelvises containing simulated hip prostheses. The anatomical areas in training and test data are different, in order to demonstrate that the proposed method extracts the beam hardening features, selectively. The results show that our method successfully corrects sinogram inconsistency by extracting beam hardening sources by means of deep learning.

Conclusion

This paper proposed a deep learning method of sinogram correction for beam hardening reduction in CT for the first time. Conventional methods for beam hardening reduction are based on regularizations, and have the fundamental drawback of being not easily able to use manifold CT images, while a deep learning approach has the potential to do so.
Measurements of self‐efficacy in musculoskeletal rehabilitation: A systematic review
Authors: Picha Kelsey J. , Jochimsen Kate N. , Heebner Nicholas R. , Abt John P. , Usher Ellen L. , Capilouto Gilson , Uhl Tim L.
Published: September 2018

Objectives

Low self‐efficacy is a barrier to rehabilitation adherence. Before an intervention can be implemented to improve self‐efficacy, assessment is required. It is currently unknown if a standard measure of self‐efficacy has been used to assess this in patients with musculoskeletal conditions, specifically for home exercise programmes (HEPs). The aim of the present study was to determine which self‐efficacy scales are being used in conjunction with exercise adherence, identify if any scale has been developed to evaluate self‐efficacy for HEPs and evaluate their psychometric properties.

Methods

Data sources included CINAHL, MEDLINE, Pubmed, PsycInfo, and Sport Discus. Studies had to include patients suffering from a musculoskeletal injury, pain or disorder; a measure of rehabilitation adherence; and patient's self‐efficacy. The study population, self‐efficacy measurement used, study quality as identified with the Modified Downs and Black checklist, results pertaining to self‐efficacy, and level of evidence were extracted. The Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA) guidelines were followed and 29 articles were included.

Results

A total of 14 scales assessing self‐efficacy were identified but no scale to assess self‐efficacy for HEPs was found. Many scales report internal consistency but lack test–retest reliability and validity.

Conclusions

The scales identified were specific to condition or tasks, and not applicable for all musculoskeletal patient populations. It is important, both for use in the clinic and for research, that outcome measures used are reliable and valid. Unfortunately, no scale was found to assess self‐efficacy for HEPs, which is problematic as self‐efficacy is task specific. As HEPs are essential to rehabilitation, there should be a scale designed specifically to assess self‐efficacy for this task.
Improving the estimation of prognosis for glioblastoma patients by MR based hemodynamic tissue signatures
Authors: Fuster‐Garcia Elies , Juan‐Albarracín Javier , García‐Ferrando Germán A. , Martí‐Bonmatí Luis , Aparici‐Robles Fernando , García‐Gómez Juan M.
Published: September 2018

Advanced MRI and molecular markers have been raised as crucial to improve prognostic models for patients having glioblastoma (GBM) lesions. In particular, different MR perfusion based markers describing vascular intrapatient heterogeneity have been correlated with tumor aggressiveness, and represent key information to understand tumor resistance against effective therapies of these neoplasms. Recently, hemodynamic tissue signature (HTS) markers based on MR perfusion images have been demonstrated to be useful for describing the heterogeneity of GBM at the voxel level, as well as demonstrating significant correlations with the patient's overall survival. In this work, we analyze the abilities of these markers to improve the conventional prognostic models based on clinical, morphological, and demographic features. Our results, in both the regression and classification tests, show that inclusion of the HTS markers improves the reliability of prognostic models. The HTS method is fully automatic and it is available for research use at http://www.oncohabitats.upv.es.
Partial amniotic carbon dioxide insufflation for fetal surgery
Authors: Skinner Sasha , DeKoninck Philip , Crossley Kelly , Amberg Benjamin , Deprest Jan , Hooper Stuart , Hodges Ryan
Published: September 2018

Partial amniotic carbon dioxide insufflation (PACI) involves insufflating the amniotic sac with carbon dioxide (CO2) and, in some cases, draining some of the amniotic fluid. The creation of a gaseous intra‐amniotic compartment improves visualization, even in the presence of limited bleeding, and creates the work space required for complex fetoscopic procedures. Clinically, PACI is mostly used to perform fetoscopic myelomeningocele (MMC) repair, enabling a minimally invasive alternative to open fetal surgery. However, evidence of the fetal safety of PACI is limited. Previous animal experiments in sheep demonstrate that PACI induces fetal hypercapnia and acidosis with largely unknown short and longer term implications. In this review, we examine the literature for the physiological effects of intrauterine insufflation pressure, duration, humidity, and the role of maternal hyperventilation on fetal physiology and well‐being.
Crystallisation and spherulite morphology of polylactide stereocomplex
Authors: Shyr Tien‐Wei , Ko Huan‐Chieh , Wu Tzu‐Ming , Wu Tzong‐Ming
Published: September 2018

In this study we investigated the crystallisation behaviours of stereocomplex crystals in poly(l‐lactic acid)/poly(d‐lactic acid) (PLLA/PDLA) blends (LD blends) of various weight ratios. The crystallisation and melting behaviours were studied using DSC, and the crystal structure was analysed through wide‐angle X‐ray diffraction. The morphology of homocrystals and stereocomplex crystals in the blends was examined using a hot‐stage polarising microscope and a scanning electron microscope. The DSC results showed that homocrystals and stereocomplex crystals were present in all LD blends except that with 50 wt% PLLA/50 wt% PDLA; in this blend, only stereocomplex crystals were present. The regime II → III transition temperature of stereocomplex crystals in a Lauritzen–Hoffman plot of the LD blends was determined to be 165 °C. A concentric spherulite consisting of stereocomplex crystals and homocrystals formed under two‐step isothermal crystallisation conditions with three growth stages was observed. The confined spherulitic growth rate in the concentric spherulite and the unrestricted spherulitic growth rate in individual spherulites were also analysed. © 2018 Society of Chemical Industry
Dynamic supramolecular polymers built from cucurbit[n]urils and viologens
Authors: Correia Henrique Dias , Chowdhury Shagor , Ramos Ana Paula , Guy Laure , Demets Grégoire Jean‐François , Bucher Christophe
Published: September 2018

This review article focuses on supramolecular assemblies involving cucurbit[n]uril‐based containers and viologen guests as key building elements. Cucurbit[n]urils (CB[n], n = 5–8,10) are fascinating hosts forming a wide range of inclusion complexes (caviplexes) with 4,4′‐bipyridinium salts, known as viologens, either as discrete 1:1 inclusion compounds with CB[7] or as ternary inclusion compounds involving two hosts or two guests (2:1 with CB[7] and 1:2 or 1:1:1 with CB[8]). This property is currently being actively exploited to design and prepare self‐assembled dynamic stimuli‐responsive supramolecular polymers including gels, vesicles, films and organized arrays of polymeric microspheres or nanoparticles. This review highlights the main benefits of such polymers and gives an overview of the achievements and progress made in this field over the past decades. © 2018 Society of Chemical Industry
Employing (half‐)titanocene complexes as initiators for the synthesis of end‐functionalized polylactides by coordination polymerization
Authors: Patias Georgios , Choinopoulos Ioannis , Koinis Spyros , Pitsikalis Marinos
Published: September 2018

Seven (half‐)titanocene alkoxide complexes, [Cp2TiCl(OEt)], [Cp2TiCl(O‐2‐Bu)], [Cp2TiCl(OCH2CF2CF2H)], [CpTiCl2(OEt)], [CpTiCl2(O‐(S)‐2‐Bu)], [CpTiCl2(OCH2CF3)], and [Cp2TiCl(OCH2CF3)], were synthesized and employed in lactide coordination polymerization. These organotitanium (IV) compounds proved to be very efficient initiators for the ring‐opening polymerization of enantiomeric l‐lactide and racemic mixture of rac‐lactide, leading to end‐functionalized polymers. Kinetic studies illustrated that these compounds produce well‐defined polymers in a controlled manner. This was further demonstrated by synthesizing poly(l‐lactide‐b‐hexyl isocyanate) diblock copolymer. The effect of the alkoxy end groups on the thermal behavior of the polymers was also studied by thermogravimetric analysis and differential scanning calorimetry. The polymers were characterized using size exclusion chromatography and proton nuclear magnetic resonance spectroscopy. The optical properties of the diblock copolymer were also investigated. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 2192–2202