bluuebunny/crossref_metadata_2025 huggingface dataset:
Implementing and expanding safe abortion care: An international comparative case study of six countries
Authors: Chavkin Wendy , Stifani Bianca M. , Bridgman‐Packer David , Greenberg Jamie M.S. , Favier Mary
Published: October 2018

We conducted a comparative case study‐based investigation of health sector strategies that were useful in expanding or establishing new abortion services. We selected geographically diverse countries from across the human development index if they had implemented new abortion laws, or changed interpretations of existing laws or policies, within the past 15 years (Colombia, Ethiopia, Ghana, Portugal, South Africa, and Uruguay). Factors facilitating the expansion of services include use of a public health frame, situating abortion as one component of a comprehensive reproductive health package, and including country‐based health and women's rights organizations, medical and other professional societies, and international agencies and nongovernment organizations in the design and rollout of services. Task sharing and the use of techniques that do not require much infrastructure, such as manual vacuum aspiration and medical abortion, are important for rapid establishment of services, especially in low‐resource settings. Political will emerged as the key factor in establishing or expanding access to safe abortion services.
Searching for tryptase in the RBL‐2H3 mast cell model: Preparation for comparative mast cell toxicology studies with zebrafish
Authors: Shim Juyoung K. , Kennedy Rachel H. , Weatherly Lisa M. , Abovian Andrew V. , Hashmi Hina N. , Rajaei Atefeh , Gosse Julie A.
Published: October 2018

Mast cells comprise a physiologically and toxicologically important cell type that is ubiquitous among species and tissues. Mast cells undergo degranulation, in which characteristic intracellular granules fuse with the plasma membrane and release many bioactive substances, such as enzymes β‐hexosaminidase and tryptase. Activity of mast cells in the toxicology model organism, zebrafish, has been monitored via tryptase release and cleavage of substrate N‐α‐benzoyl‐dl‐Arg‐p‐nitroanilide (BAPNA). An extensively used in vitro mast cell model for studying toxicant mechanisms is the RBL‐2H3 cell line. However, instead of tryptase, granule contents such as β‐hexosaminidase have usually been employed as RBL‐2H3 degranulation markers. To align RBL‐2H3 cell toxicological studies to in vivo mast cell studies using zebrafish, we aimed to develop an RBL‐2H3 tryptase assay. Unexpectedly, we discovered that tryptase release from RBL‐2H3 cells is not detectable, using BAPNA substrate, despite optimized assay that can detect as little as 1 ng tryptase. Additional studies performed with another substrate, tosyl‐Gly‐Pro‐Lys‐pNA, and with an enzyme‐linked immunosorbent assay, revealed a lack of tryptase protein released from stimulated RBL‐2H3 cells. Furthermore, none of the eight rat tryptase genes (Tpsb2, Tpsab1, Tpsg1, Prss34, Gzmk, Gzma, Prss29, Prss41) is expressed in RBL‐2H3 cells, even though all are found in RBL‐2H3 genomic DNA and even though β‐hexosaminidase mRNA is constitutively expressed. Therefore, mast cell researchers should utilize β‐hexosaminidase or another reliable marker for RBL‐2H3 degranulation studies, not tryptase. Comparative toxicity testing in RBL‐2H3 cells in vitro and in zebrafish mast cells in vivo will require use of a degranulation reporter different from tryptase.
Chronic cadmium exposure induced hepatic cellular stress and inflammation in aged female mice
Authors: Zhang Jun , Wang Yan , Fu Lin , Wang Bo , Ji Yan‐Li , Wang Hua , Xu De‐Xiang
Published: October 2018

Previous studies have revealed that acute cadmium (Cd) exposure led to inflammation in different organs through an oxidative stress mechanism. However, whether chronic Cd exposure induces inflammation in liver and the mechanistic link between inflammation and cell stress remains unclear. In the present study, we investigated the effects of chronic Cd exposure on hepatic cellular stress and inflammatory responses. Female CD1 mice were administrated with CdCl2 (10 and 100 mg/L) in drinking water for 57 weeks. Our results showed that the mRNA levels of Inos and the protein content of HO‐1, markers of oxidative stress, were markedly increased in Cd‐treated mice. In addition, the protein level of GRP78, the chaperone of endoplasmic reticulum (ER) stress, was significantly increased in Cd‐treated mice. The expression of the proteins CHOP and peIF2α, two proteins downstream of ER stress, was also upregulated in the Cd‐100 mg/L and Cd‐10 mg/L group, respectively. Moreover, there were increased inflammatory cells existing in liver after Cd administration. Besides, there was a significant elevation in the mRNA level of Mip‐2, Il‐10 and Il‐12 in the Cd‐100 mg/L group. The mRNA level of Tgf‐β was also upregulated in Cd‐treated mice. Moreover, we also found that the number of Ki67‐positive hepatic cells was increased in the Cd‐10 mg/L group. Hence, our results indicated that chronic Cd exposure induced oxidative stress, ER stress, inflammatory responses and proliferation in the liver of aged female mice.
Fabrication, microstructure, and properties of a biodegradable Mg‐Zn‐Ca clip
Authors: Bai Hao , He Xianghui , Ding Pengfei , liu Debao , Chen Minfang
Published: October 2018

An Mg‐Zn‐Ca alloy biodegradable clip was fabricated by combining hot extrusion and blanking processing. Microstructure evolution was investigated by optical microscopy and electron backscattering diffraction and the occlusion properties of Mg‐Zn‐Ca alloy clip were evaluated in vitro and in vivo. It was found that the as‐extruded Mg‐Zn‐Ca alloy exhibited a typical fiber microstructure. After blanking, the basal texture intensity increased because of the work hardening effect. Subsequent annealing treatment of the blanking clip can significantly weaken the texture while improving the ductility of the Mg‐Zn‐Ca alloy. It was found that Mg‐Zn‐Ca clips can maintain closure performance for 2 weeks in in vitro immersion tests while in vivo tests indicated that the Mg‐3Zn‐0.2Ca alloy clips fabricated by this preparation processing successfully occluded the blood vessels. These results suggest that the developed Mg‐3Zn‐0.2Ca alloy clip is a suitable candidate for biodegradable soft tissue fixation devices such as surgical clips. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 1741–1749, 2019.
Systematic review and meta‐analysis on non‐opioid analgesics in palliative medicine
Authors: Schüchen Robert H. , Mücke Martin , Marinova Milka , Kravchenko Dmitrij , Häuser Winfried , Radbruch Lukas , Conrad Rupert
Published: October 2018

Non‐opioid analgesics are widely used for pain relief in palliative medicine. However, there is a lack of evidence‐based recommendations addressing the efficacy, tolerability, and safety of non‐opioids in this field. A comprehensive systematic review and meta‐analysis on current evidence can provide a basis for sound recommendations in clinical practice. A database search for controlled trials on the use of non‐opioids in adult palliative patients was performed in Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, PsycINFO, and EMBASE from inception to 18 February 2018. Endpoints were pain intensity, opioid‐sparing effects, safety, and quality of life. Studies with similar patients, interventions, and outcomes were included in the meta‐analyses. Our systematic search was able to only identify studies dealing with cancer pain. Of 5991 retrieved studies, 43 could be included (n = 2925 patients). There was no convincing evidence for satisfactory pain relief by acetaminophen alone or in combination with strong opioids. We found substantial evidence of moderate quality for a satisfactory pain relief in cancer by non‐steroidal anti‐inflammatory drugs (NSAIDs), flupirtine, and dipyrone compared with placebo or other analgesics. There was no evidence for a superiority of one specific non‐opioid. There was moderate quality of evidence for a similar pain reduction by NSAIDs in the usual dosage range compared with up to 15 mg of morphine or opioids of equianalgesic potency. The combination of NSAID and step III opioids showed a beneficial effect, without a decreased tolerability. There is scarce evidence concerning the combination of NSAIDs with weak opioids. There are no randomized‐controlled studies on the use of non‐opioids in a wide range of end‐stage diseases except for cancer. Non‐steroidal anti‐inflammatory drugs, flupirtine, and dipyrone can be recommended for the treatment of cancer pain either alone or in combination with strong opioids. The use of acetaminophen in the palliative setting cannot be recommended. Studies are not available for long‐term use. There is a lack of evidence regarding pain treatment by non‐opioids in specific cancer entities.
Heparan sulfate as a regulator of inflammation and immunity
Authors: Collins Laura E , Troeberg Linda
Published: October 2018

Heparan sulfate is found on the surface of most cell types, as well as in basement membranes and extracellular matrices. Its strong anionic properties and highly variable structure enable this glycosaminoglycan to provide binding sites for numerous protein ligands, including many soluble mediators of the immune system, and may promote or inhibit their activity. The formation of ligand binding sites on heparan sulfate (HS) occurs in a tissue- and context-specific fashion through the action of several families of enzymes, most of which have multiple isoforms with subtly different specificities. Changes in the expression levels of these biosynthetic enzymes occur in response to inflammatory stimuli, resulting in structurally different HS and acquisition or loss of binding sites for immune mediators. In this review, we discuss the multiple roles for HS in regulating immune responses, and the evidence for inflammation-associated changes to HS structure.

Review of the established and emerging roles of heparan sulfate as an immune regulator through binding inflammatory ligands in the microenvironment and on cell surfaces.
Arsenic phytotoxicity and accumulation in rice seedlings grown in arsenic‐contaminated soils as influenced by the characteristics of organic matter amendments and soils
Authors: Syu Chien-Hui , Wu Pei-Rung , Lee Chia-Hsing , Juang Kai-Wei , Lee Dar-Yuan
Published: October 2018

Organic matter (OM) application into soils is a common agricultural practice. Previous studies have shown that in arsenic (As)‐contaminated paddy soils, OM has the potential to alter the behavior of As and affects the growth and As accumulation of rice plants. In this study, pot experiments were conducted to investigate the differences in the amounts of As released into soil solutions, its toxicity, and accumulation in rice seedlings caused by application of three different OM amendments [soybean meal (SB), sugarcane dreg compost (SC), and cattle‐dung compost (CD)]. These OM amendments were each applied to three As‐contaminated soils, Guandu (Gd), Pinchen (Pc), and Chengchung (Cf), which have different characteristics. The results indicate that after addition of two easily decomposable OMs (SB and SC), the As toxicity and concentrations increased in rice plants, especially in As‐spiked Cf soils which had low As retention capacity. This was the result of elevated As concentration in soil solutions due to a decrease in soil redox potential and competition between dissolved organic carbon (DOC) and As for sorption sites, as well as the formation of As–DOC complexes. However, there were no significant effects on plant growth and As accumulation in rice seedlings after treatments with CD (not easily decomposable OM). Another important finding was that the amount of iron plaque on the surface of rice roots increased with OM amendments in the Gd soils rich in iron oxides and hydroxides, thus reducing the As uptake by rice plants. These results suggest that the characteristics of OM and soils should be considered when OM amendments are applied to As‐contaminated soils.
Putting Foucault to work in tourism research
Authors: Wight A. Craig
Published: October 2018

This paper reflects on Foucault's Archaeology of Knowledge as a methodological approach in tourism research. It offers lessons from recent research focused on critiquing heritage sites and museums as examples of destination discourse. The aim is to tackle an increasingly acknowledged reluctance to declare method when carrying out Foucauldian analysis. The paper reflects on the role of discourse analysis as a methodology in tourism research before considering Foucault's specific contribution. It then offers a synthesis of Foucault's methodological ideas and presents these as an adaptable discursive analytic that can be applied to a range of tourism research contexts. It considers the methodological limits that are associated with the deployment of Foucault before a conclusion considers the novel contribution of the paper, which is an adaptable discursive analytic for tourism researchers to contemplate when thinking about how to “do” Foucauldian discourse analysis.
Technologically achievable soil organic carbon sequestration in world croplands and grasslands
Authors: Batjes Niels H.
Published: October 2018

Reported potentials for sequestration of carbon in soils of agricultural lands are overly optimistic because they assume that all degraded cropland and grassland can be subjected to best management practices. Two approaches for estimating this potential are presented. Method 1 (M1) considers literature‐derived best estimates for annual soil organic carbon (SOC) gains (Mg C ha−1) by bioclimatic zone; Method 2 (M2) assumes an annual C increase of 3 to 5 promille with respect to present SOC mass (similar to the French ‘4 pour mille’ initiative). Four management scenarios are considered, capturing the varying level of plausibility of meeting the full technological potential. According to M1, achievable gains range from 0.05–0.12 Pg C yr−1 to 0.14–0.37 Pg C yr−1, with a technological potential of 0.32–0.86 Pg C yr−1. For M2, these are 0.07–0.12 Pg C yr−1, 0.21–0.35 Pg C yr−1, and 0.60–1.01 Pg C yr−1. Consideration of the technological potential only and use of a proportional annual increase in SOC (M2), rather than using best estimates for soil carbon gains by bioclimatic zone (M1), will provide too ‘bright a picture’ in the context of rehabilitating degraded lands and mitigating/adapting to climate change. Further, M2 assumes that possible C gains will be greatest where present SOC stocks are highest, which is counter‐intuitive. Although all measures aimed at increasing SOC content should be encouraged due to the creation of win‐win situations, it is important to create a realistic picture of the amount of SOC gains that are feasible based on bioclimatic and management implementation constraints.
Hydrologic controls on pCO2 and CO2 efflux in US streams and rivers
Authors: Liu Shaoda , Raymond Peter A.
Published: October 2018

Streams and rivers emit petagrams of CO2, yet there is little known about how discharge variability impacts stream CO2 at broad scales. This article analyzed changes of pCO2 and CO2 efflux with discharge in 813 conterminous US streams and rivers. Half of the streams and rivers (49%) showed positive pCO2–discharge responses, while significantly more (80%) showed positive CO2 efflux–discharge responses. More CO2 efflux therefore occurred at higher discharge. While CO2 efflux tended to increase with discharge at all stream orders, pCO2 tended to decrease with discharge in small rivers (stream order 1–6) and increase in large rivers (stream order 7–10). Small streams and rivers tended to release more CO2 at higher discharge due to highly responsive gas transfer velocity. While high CO2 efflux in small streams (stream order 1–3) pointed to strong terrestrial input, high CO2 responsiveness in large rivers was likely due to increased riverine metabolism and river–corridor exchanges.
Setting appropriate pain expectations: Lessons learned from a clinical trial
Authors: Bonati Lauren M. , Quatrano Nicola A. , Sadeghpour Mona , Arndt Kenneth A. , Dover Jeffrey S.
Published: October 2018

Objective

This retrospective study compares subject‐reported pain levels and expectations set forth by industry and treating physicians during a clinical trial of an energy based device. The physiologic and emotional aspects of pain expectations are discussed and recommendations are made for strategic patient counseling.

Materials and Methods

Average and mode pain scores were collected from the records of a previously conducted clinical trial investigating a radiofrequency microneedling device at three different settings. The trial protocol and device manual were reviewed to ascertain language regarding procedural pain. Treating physicians were asked how they learned about procedural pain and how they described it to subjects. Subject‐reported pain scores and verbal pain descriptors from the device manual and trial protocol were translated onto validated pain scales, the Numerical Rating Scale (NRS), and the Verbal Rating Scale (VRS), for comparison.

Results

A total of 90 procedural pain scores were collected from 30 subject charts. The average procedural pain scores for three different device settings were 5.3, 6.7, and 4.6 out of 10 and the mode pain score was 6 out of 10. This translated to a 5–6 and 7–8 on the NRS, respectively and classification as “painful but bearable” and “considerable pain” on the VRS. Industry sourced pain levels translated to a 2–4 on the NRS and classification as “little pain” on the VRS.

Conclusion

Subject‐reported pain scores were higher than those set forth by industry materials and personnel. Physicians should be wary of manufacturer materials or anecdotal evidence that might mislead patients and cause undue physiological or emotional stress. Lasers Surg. Med. 9999:XX–XX, 2018. © 2018 Wiley Periodicals, Inc.
High frequency somatosensory stimulation in dystonia: Evidence fordefective inhibitory plasticity
Authors: Erro Roberto , Rocchi Lorenzo , Antelmi Elena , Liguori Rocco , Tinazzi Michele , Berardelli Alfredo , Rothwell John , Bhatia Kailash P.
Published: October 2018

Background

Apart from motor symptoms, multiple deficits of sensory processing have been demonstrated in dystonia. The most consistent behavioural measure of this is abnormal somatosensory temporal discrimination threshold, which has recently been associated with physiological measures of reduced inhibition within the primary somatosensory area. High‐frequency repetitive sensory stimulation is a patterned electric stimulation applied to the skin through surface electrodes that has been recently reported to shorten somatosensory temporal discrimination in healthy subjects and to increase the resting level of excitability in several different types of inhibitory interaction in the somatosensory and even motor areas.

Objectives

We tested whether high‐frequency repetitive sensory stimulation could augment cortical inhibition and, in turn, ameliorate somatosensory temporal discrimination in cervical dystonia.

Methods

Somatosensory temporal discrimination and a number of electrophysiological measures of sensorimotor inhibition and facilitation were measured before and after 45 minutes of high‐frequency repetitive sensory stimulation.

Results

As compared with a group of healthy volunteers of similar age, in whom high‐frequency repetitive sensory stimulation increased inhibition and shortened somatosensory temporal discrimination, patients with cervical dystonia showed a consistent, paradoxical response: they had reduced suppression of paired‐pulse somatosensory evoked potentials, as well as reduced high‐frequency oscillations, lateral inhibition, and short interval intracortical inhibition. Somatosensory temporal discrimination deteriorated after the stimulation protocol, and correlated with reduced measures of inhibition within the primary somatosensory cortex.

Conclusions

We suggest that patients with dystonia have abnormal homeostatic inhibitory plasticity within the sensorimotor cortex and that this is responsible for their paradoxical response to high‐frequency repetitive sensory stimulation. © 2018 International Parkinson and Movement Disorder Society
On the local and global asymptotic stability of the Degn‐Harrison reaction‐diffusion model
Authors: Abbad Abir , Bendoukha Samir , Abdelmalek Salem
Published: October 2018

In this paper, we study the well‐known Degn‐Harrison reaction diffusion model. We are concerned with the local and global asymptotic stability of the system. Weaker conditions than those of previous studies are derived and validated using Matlab computer simulations.
The effects of augmentation cystoplasty and botulinum toxin injection on patient‐reported bladder function and quality of life among individuals with spinal cord injury performing clean intermittent catheterization
Authors: Myers Jeremy B. , Lenherr Sara M. , Stoffel John T. , Elliott Sean P. , Presson Angela P. , Zhang Chong , Rosenbluth Jeffery , Jha Amitabh , Patel DarshanP , Welk Blayne ,   for the Neurogenic Bladder Research Group (NBRG. org)
Published: October 2018

Aims

Clean intermittent catheterization (CIC) is recommended after spinal cord injury (SCI) because it has the least complications, however, CIC has a high discontinuation rate. We hypothesized that bladder botulinum toxin injection or augmentation cystoplasty may improve satisfaction with CIC.

Methods

The NBRG registry is a multicenter, prospective, observational study asking SCI participants about neurogenic bladder (NGB) related quality of life (QoL). In this study, participants performing CIC as primary bladder management were categorized into 3 groups: (1) CIC alone (CIC); (2) CIC with botulinum toxin (CIC‐BTX); and (3) CIC with augmentation cystoplasty (CIC‐AUG). Outcomes included primary: Neurogenic Bladder Symptom Score (NBSS) and SCI‐QoL Bladder Management Difficulties, and secondary: NBSS subdomains (Incontinence, Storage & Voiding, Consequences) and the NBSS final question (satisfaction with urinary function). Multivariable regression, controlling for multiple factors was used to establish differences between the three groups.

Results

Eight hundred seventy‐nine participants performed CIC as primary bladder management and had the following characteristics: mean age 43.4 (±12.9) and years from injury 13.7 (±10.7), tetraplegia in 284 (32%), and 543 (62%) were men. Bladder management was CIC in 593 (67%), CIC‐BTX in 161 (19%), and CIC‐AUG in 125(15%). Primary outcomes: CIC‐AUG had associated improved total NBSS versus CIC(−3.2(−5.2 to −1.2), P = 0.001 and CIC‐BTX(−3.9(−6.3 to −1.6), P = 0.001), CIC‐AUG also had better SCI‐QoL Difficulties scores versus CIC(−4(−5.48 to −2.53, P < 0.001) and CIC‐BTX(−4.4(−6.15 to −2.65, P < 0.001). Secondary outcomes: CIC‐AUG had associated improved Incontinence and Satisfaction scores versus CIC and CIC‐BTX.

Conclusions

Compared to patients performing CIC with or without botulinum toxin treatment, those with augmentation cystoplasty had associated better urinary function and satisfaction with their urinary symptoms.
Sloshing effects on supersonic flutter characteristics of a circular cylindrical shell partially filled with liquid
Authors: Zarifian Pourya , Ovesy Hamid Reza , Firouz‐Abadi Rouhollah Dehghani
Published: October 2018

This paper aims to revisit the effect of sloshing on the flutter characteristics of a partially liquid‐filled cylinder. A computational fluid‐structure interaction model within the framework of the finite element method is developed to capture fluid‐structure interactions arising from the sloshing of the internal fluid and the flexibility of its containing structure exposed to an external supersonic airflow. The internal liquid sloshing is represented by a more sophisticated model, referred to as the liquid sloshing model, and the shell structure is modeled by Sanders' shell theory. The aerodynamic pressure loading is approximated by the first‐order piston theory. The initial geometric stiffness due to prestresses in the initial configuration stemming from the fluid hydrostatic pressure, internal pressure, and axial compression load is also considered. The obtained results reveal that the sloshing of the internal fluid has little influence on the supersonic flutter boundary of a cylinder partially filled with liquid, at least for the case considered here. It is also shown that the critical freestream static pressure predicted by the sloshing model is negligibly larger than that calculated by the hydroelastic model of the internal fluid, which means that the sloshing of the internal fluid slightly overestimates the flutter boundary.
Stakeholder model for community economic development in alleviating poverty in municipalities in South Africa
Authors: Ndaguba Emeka Austin , Hanyane Barry
Published: October 2018

Governments globally have several responsibilities to its citizen, and one of these responsibilities is the improvement in the living standard and to stimulate social well‐being and sustainability in communities. A meta‐review of over a 100 article was conducted of both the qualitative and quantitative method related to the antecedents to business models, community economic development, and poverty alleviation. The basis for the paper is the proposition of the stakeholder model for implementing Community Economic Development in municipalities for alleviating poverty in South Africa.
The rise of the shadow economy: An Indian perspective
Authors: Menon Priyanka
Published: October 2018

This study was undertaken to understand the importance of the shadow economy, which is often misunderstood and misquoted. We come to an understanding of why this is an uproar regarding black money generation in India. This paper is an attempt to bring forward past evidences and current situation to understand the system through discussing various points of views in the literature. The paper concludes with bringing out the difference in black wealth and black money and the impact of both on the economy and answers the question—Is black money really bad for the economy? It is a hope that these results will be useful to policymakers and stakeholder to make policies that cater to all.
Decoding transcriptomic intra‐tumour heterogeneity to guide personalised medicine in ovarian cancer
Authors: Tan Tuan Zea , Heong Valerie , Ye Jieru , Lim Diana , Low Jeffrey , Choolani Mahesh , Scott Clare , Tan David Shao Peng , Huang Ruby Yun‐Ju
Published: October 2018

The evaluation of intra‐tumour heterogeneity (ITH) from a transcriptomic point of view is limited. Single‐cell cancer studies reveal significant genomic and transcriptomic ITH within a tumour and it is no longer adequate to employ single‐subtype assignment as this does not acknowledge the ITH that exists. Molecular assessment of subtype heterogeneity (MASH) was developed to comprehensively report on the composition of all transcriptomic subtypes within a tumour lesion. Using MASH on 3431 ovarian cancer samples, correlation and association analyses with survival, metastasis and clinical outcomes were performed to assess the impact of subtype composition as a surrogate for ITH. The association was validated on two independent cohorts. We identified that 30% of ovarian tumours consist of two or more subtypes. When biological features of the subtype constituents were examined, we identified significant impact on clinical outcomes with the presence of poor prognostic subtypes (Mes or Stem‐A). Poorer outcomes correlated with having higher degrees of poor prognostic subtype populations within the tumour. Subtype prediction in several independent datasets reflected a similar prognostic trend. In addition, paired analysis of primary and recurrent/metastatic tumours demonstrated Mes and/or Stem‐A subtypes predominated in recurrent and metastatic tumours regardless of the original primary subtype. Given the biological and prognostic value in delineating individual subtypes within a tumour, a clinically applicable MASH assay using NanoString® technology was developed as a classification tool to comprehensively describe constituents of molecular subtypes. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Fabrication and characterization of eco‐friendly human‐hair derived porous carbon‐filled carbon fabric‐reinforced polymer composites
Authors: Kumar Ravindra , Varshney Suyash , Kar Kamal K. , Dasgupta Kinshuk
Published: October 2018

The effects of human hair‐derived porous carbon (HHC) as an eco‐friendly reinforcing filler in the carbon fabric‐reinforced phenolic matrix composites (CPCs) are evaluated through micro‐structural characterization studies, tensile, and flexural tests, dynamic mechanical analysis, density and electrical conductivity measurements. Various interfacial interaction parameters like reinforcement efficiency, C‐factor, adhesion factor, and so on are also calculated and compared for understanding the effects of HHC in composites. Conventional hand‐layup technique is used for impregnation of slurry made of phenolic resin and 0–50 wt% HHC on carbon fabric followed by stacking and curing through hot pressing to get laminates of CPCs. Significant improvement in mechanical, viscoelastic and electrical properties are observed over unfilled composite for all investigated HHC loadings. However, 30–40 wt% filler loading gives the optimum balance of properties. The results show ∼15, 93, 50, 85, and 132% increase in tensile strength, Young's modulus, flexural strength, flexural modulus, and storage modulus, respectively. Moreover drastic gain (1,500%) in electrical conductivity and substantial enhancement in thermal stability of CPCs make HHC as a cheap alternative reinforcing filler for structural composite applications working under thermo‐mechanical loads. POLYM. COMPOS., 40:E1573–E1587, 2019. © 2018 Society of Plastics Engineers
Wall Slip of Linear Polymer Melts During Ultrasonic‐assisted Micro‐injection Molding
Authors: Gao Shan , Qiu Zhongjun , Ouyang Junhao , Yang Yujun
Published: October 2018

The wall slip of linear polymer melts under ultrasonic vibration is investigated by correcting the slip mechanism, and melt flow behaviors in ultrasonic‐assisted micro‐injection molding (UμIM) method are discussed. Based on the effect mechanism of ultrasonic vibration on the melt, theoretical models of the critical shear stresses for the onset of weak and strong wall slip during UμIM are established, and the change in rheological properties due to the onset of wall slip under ultrasonic vibration is experimental investigated by a built measurement system. The results show that the onset of weak and strong wall slip of the melt in micro cavity are promoted by ultrasonic vibration, which agree with the built theoretical models, and the melt filling capability in micro cavity is enhanced by reducing apparent viscosity and releasing shear stress of the polymer melt, which improves the molding quality of micro polymer parts via UμIM method. POLYM. ENG. SCI., 59:E7–E13, 2019. © 2018 Society of Plastics Engineers
In silico investigation of the coumarin‐based organic semiconductors for the possible use in organic electronic devices
Authors: Siddiqui Shamoon Ahmad
Published: October 2018

First principle calculations were carried out to investigate the electron injection, electron coupling, electronic, and photophysical properties of two coumarin derivatives coumarin 102 and coumarin 153. The initial molecular geometries of both derivatives were optimized in the ground state using density functional theory in conjugation with B3LYP functional and 6‐31G(d,p) basis set. The highest occupied molecular orbital (HOMO) of coumarin 102 and coumarin 153 were observed beneath the redox couple, whereas the lowest unoccupied molecular orbital (LUMO) of both coumarin derivatives were observed above the conduction band of TiO2. The time‐dependent density functional theory has been used to calculate the excitation energies at PCM‐CAM‐B3LYP/6‐31G(d,p) level. Based upon the calculation of hole reorganization energy λh and electron reorganization energy λe, it has been observed that both coumarin 102 and coumarin 153 are hole transport materials. The electronic coupling constant, electron injection, and light harvesting efficiencies of these coumarin derivatives are higher than coumarin. This clearly indicates that these derivatives would be excellent photosensitizers. Finally, the effect of electric field on the dipole moment, HOMO, LUMO, and HOMO‐LUMO gap has been thoroughly observed to check the competency of these derivatives for the possible use in organic field effect transistors.
Photocrosslinked methacrylated poly(vinyl alcohol)/hydroxyapatite nanocomposite hydrogels with enhanced mechanical strength and cell adhesion
Authors: Zhou Ding , Dong Qi , Liang Kaili , Xu Weilin , Zhou Yingshan , Xiao Pu
Published: October 2018

Poly(vinyl alcohol) (PVA) hydrogels with high water content, good load‐bearing property, low frictional behavior as well as excellent biocompatibility have been considered as promising cartilage replacement materials. However, the lack of sufficient mechanical properties and cell adhesion are two critical barriers for their application as cartilage substitutes. To address these problems, herein, methacrylated PVA with low degree of substitution of methacryloyl group has been synthesized first. Then, methacrylated PVA‐glycidyl methacrylate/hydroxyapatite (PVA‐GMA/Hap) nanocomposite hydrogels have been developed by the photopolymerization approach subsequently. Markedly, both pure PVA‐GMA hydrogel and PVA‐GMA/Hap nanocomposite hydrogels exhibit excellent performance in compressive tests, and they are undamaged during compressive stress–strain tests. Moreover, compared to pure PVA‐GMA hydrogels, 8.5‐fold, 7.4‐fold, and 14.2‐fold increase in fracture stress, Young's modulus and toughness, respectively, can be obtained for PVA‐GMA/Hap nanocomposite hydrogels with 10 wt % Hap nanoparticles. These enhancements can be ascribed to the intrinsic property of PVA‐GMA and strong hydrogen bonding interactions between PVA‐GMA chain and Hap nanoparticles. More interestingly, significant improvement in the cell adhesion can also be successfully achieved by incorporation of Hap nanoparticles. These biocompatible nanocomposite hydrogels have great potential to be used as cartilage substitutes. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1882–1889
Modifying the morphology via employing rigid phenyl side chains achieves efficient nonfullerene polymer solar cells
Authors: Zhong Yaqian , Liu Deyu , Zhang Kaili , Li Yonghai , Sun Mingliang , Yu Liangmin , Li Feng , Liu Huizhou , Yang Renqiang
Published: October 2018

As a promising electron‐deficient (acceptor) unit, fluorinated benzotriazole (TAZ) was used widely to construct wide bandgap polymers for nonfullerene polymer solar cells (NF‐PSCs). However, due to the S…F noncovalent interaction, the unit show good planarity and strong aggregation, which was not beneficial for the blend with the elongated nonfullerene acceptors. Here, we tried to choose new donor polymers to match with TAZ unit, which was expected to destroy the interchain aggregation of polymer and form favorable morphology of blends. Two new wide‐bandgap polymers PBDTsPhPh‐T1 and PBDTsThPh‐T1 based on the unsymmetrical benzodithiophene (BDT) units with a benzene ring as lever arms were synthesized. As a result, these two polymers blend well with nonfullerene acceptor (ITIC). And then, PBDTsPhPh‐T1 and PBDTsThPh‐T1‐based devices exhibit the decent photovoltaic properties with high power conversion efficiencies of 8.85 and 9.34%, respectively. The work demonstrates that the unsymmetrical BDT units could be outstanding for building donor materials toward high‐performance NF‐PSCs. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 2762–2770
The energy cascade associated with daily variability of the North Atlantic Oscillation
Authors: Castanheira José M. , Marques Carlos A. F.
Published: October 2018

An analysis of anomalies of the energy cascade associated with daily fluctuations of the North Atlantic Oscillation (NAO) is presented here. The analysis consists of a detailed version of the Lorenz energy cycle, which decomposes the energy flows into baroclinic and barotropic terms and into zonal mean and eddy components, and was applied to the 6‐hourly ERA‐Interim reanalysis for the period of 1979–2016. The obtained results show that the positive NAO phase is preceded by a significant increase of synoptic baroclinic eddy activity. The eddy available potential energy is converted into kinetic energy and transferred to barotropic synoptic eddies. Then, the kinetic energy is transferred upscale into the barotropic planetary waves, which produce the NAO pattern. Immediately after the positive NAO peak, there is a significant reduction of baroclinic activity, and no indication of an anomalous increase of the global‐mean baroclinic eddy activity in the 10‐day period after the peak was found. At longer lags, between 10 and 20 days, the kinetic energy of barotropic eddies shows positive anomalies consistent with the eddy–zonal mean flow feedback. We conclude that the synoptic baroclinic eddy activity forces the NAO variability, and no modulating role of the NAO in the global‐mean baroclinic eddy activity (storminess) occurs.
Preventive maintenance policy of single‐unit systems based on shot‐noise process
Authors: Qiu Qingan , Cui Lirong , Dong Qinglai
Published: October 2018

This paper develops reliability and maintenance models for a single‐unit system subject to hard failures under random environment of external shocks. Motivated by the observations of shot‐noise process in practice, the impact of shock damage on system failure behavior is characterized by random hazard rate increments. To remove such negative impact, imperfect preventive repair is performed periodically, and preventive replacement is performed after several repairs. Considering the joint effects of both random shocks and imperfect repair on the system hazard rate, we derive recursive equations for the system reliability function. Furthermore, we investigate the optimal maintenance policy that minimizes the expected cost per unit time of the system. The applicability of the reliability and maintenance model is validated by a case study on a wind turbine system.
Star‐Shaped CuS Flat Nanoflakes Reinforced Ni(OH)2 Nanosheets for Enhanced Capacitance
Authors: Reddy B. Narsimha , Gupta Govind , Ingole Pravin P.
Published: October 2018

Enhanced electrochemical capacitance of 2D‐nanosheets of Ni(OH)2 via reinforcement of star‐shaped CuS flat nanoflakes synthesized using in‐situ hydrothermal root is presented. Microscopic and structural characterization suggest the inclusion of CuS nanoflakes in the films. Reinforced CuS nanoflakes offer high surface area resulting into open‐sheet morphologies for Ni(OH)2@CuS films; contrasting with the folded sheet structures attained for the neat Ni(OH)2 films. The remarkably high bulk (10−3 S cm−1) conductivity of CuS enhances the conductivity and enable facile electron transport in the composites. Asymmetric supercapacitors constructed using Ni(OH)2@CuS and graphite as the electrodes is noted to show specific capacitances of 642 Fg−1 at current density of 1 Ag−1, good rate capability and excellent cycling stability (86% capacitance retention at the end of 1000 cycles) relative to the neat Ni(OH)2 based supercapacitor cells that shows specific capacitance of 142 Fg−1 at the same current density. The direct contact of Ni(OH)2 with the conductive CuS nanoflakes and highly porous structures of Ni(OH)2@CuS electrodes doubles the power densities of the Ni(OH)2@CuS supercapacitors than Ni(OH)2 cells due to the low ion‐diffusion resistances for charging by ions from the electrolyte, afforded by the short diffusion pathways in the composites.
Detailed Mechanistic Study of Radical Mediated Chemoselective Phosphination of Aryl Halide
Authors: Kosar Naveen , Mahmood Tariq , Hafeez Farhan , Ayub Khurshid
Published: October 2018

Phosphines play important role in organic synthesis, since they are important ligands for transition metals catalysis. Moreover, phosphines are important building blocks of supramolecular architectures, and are used in advanced material sciences. An important reaction to make phosphines is the phosphination of organic halides. In this report, the mechanistic details of radical initiated phosphination of organic halides are studied theoretically for complete reaction cycle. The mechanistic studies are performed with an accurate method (ωB97XD), which we established for similar reactions through a benchmark study. The mechanistic studies are performed with aryl bromide and aryl iodide. The results show that overall reaction follows SH2 pathway, and all steps are thermodynamically and kinetically favorable. The mechanistic outcomes of the research are in nice agreement with the recent experimental observations.
Theoretical Investigation of Difluoroboron Complex of Curcuminoid Derivatives with and without Phenyl Substituent (at Meso Position): Linear and Non‐Linear Optical Study
Authors: Raikwar Manish M. , Rhyman Lydia , Ramasami Ponnadurai , Sekar Nagaiyan
Published: October 2018

Two difluoroboron curcumin analogs and their phenylated versions were studied for their photophysical and non‐linear optical properties based on comprehensive density functional theory approach. The ground state geometry optimization, vertical excitation, and the first excited state optimization were carried out using B3LYP and CAM−B3LYP functionals with 6–31G(d) basis set. The geometry of the difluoroboron curcumin analogs was found to remain planar in both the ground and excited states. The computed vertical excitation and emission values obtained with global hybrid functional are in good correlation with the observed values. The phenylated analogs show enhancement in the photophysical properties. The linear and non‐linear optical properties were computed using two global hybrids functionals (B3LYP and BHHLYP) and a range separated hybrid functional (CAM−B3LYP) with 6–31+G(d,p) basis set. The difluoroboron curcumin analogs without the phenyl substituent have larger polarizability and hyperpolarizabiliy parameters than the phenylated analogs. The polarizability and hyperpolarizabiliy were found to be comparable with the BHHLYP and CAM−B3LYP functionals.
Copper Catalyzed C−H Activation
Authors: Kantam M. Lakshmi , Gadipelly Chandrakanth , Deshmukh Gunjan , Reddy K. Rajender , Bhargava Suresh
Published: October 2018

Activation of C−H bonds and their application in cross coupling chemistry has received a wider interest in recent years. The conventional strategy in cross coupling reaction involves the pre‐functionalization step of coupling reactants such as organic halides, pseudo‐halides and organometallic reagents. The C−H activation facilitates a simple and straight forward approach devoid of pre‐functionalization step. This approach also addresses the environmental and economical issues involved in several chemical reactions. In this account, we have reported C−H bond activation of small organic molecules, for example, formamide C−H bond can be activated and coupled with β‐dicarbonyl or 2‐carbonyl substituted phenols under oxidative conditions to yield carbamates using inexpensive copper catalysts. Phenyl carbamates were successfully synthesized in moderate to good yields by cross dehydrogenative coupling (CDC) of phenols with formamides using copper catalysts in presence of a ligand. We have also prepared unsymmetrical urea derivatives by oxidative cross coupling of formamides with amines using copper catalysts. Synthesis of N,N‐dimethyl substituted amides, 5‐substituted‐γ‐lactams and α‐acyloxy ethers was carried out from carboxylic acids using recyclable CuO nanoparticles. Copper nanoparticles afforded N‐aryl‐γ‐amino‐γ‐lactams by oxidative coupling of aromatic amines with 2‐pyrrolidinone. Reusable transition metal HT‐derived oxide catalyst was used for the synthesis of N,N‐dimethyl substituted amides by the oxidative cross‐coupling of carboxylic acids and substituted benzaldehydes. Overview of our work in this area is summarized.
Sarcomania? The Inapplicability of Sarcopenia Measurement in Predicting Incisional Hernia Development
Authors: van Rooijen M. M. J. , Kroese L. F. , van Vugt J. L. A. , Lange J. F.
Published: October 2018

Background

Incisional hernia is a frequent complication after abdominal surgery. A risk factor for incisional hernia, related to body composition, is obesity. Poor skeletal muscle mass might also be a risk factor, as it may result in weakness of the abdominal wall. However, it remains unknown if sarcopenia (i.e. low skeletal muscle mass) is a risk factor for incisional hernia. Therefore, this study aims to investigate whether a relation between sarcopenia and incisional hernia exists.

Methods

Patients from the STITCH trial, who underwent elective midline laparotomy, were included. Computed tomography examinations performed within 3 months preoperatively were used to measure the skeletal muscle index (SMI; cm2/m2). Primarily, SMI measured continuously, sarcopenia based on previously described cut‐off values for the SMI, and sarcopenia as the lowest gender‐specific SMI quartile were assessed as measures to predict incisional hernia occurrence. Secondary, the association between these three measures and post‐operative complications was investigated.

Results

In total, 283 patients (45.2% male; mean age 63.7 years; mean BMI 25.36 kg/m2) were included, of whom 52 (18%) developed an incisional hernia. Mean SMI was 44.23 cm2/m2 (SD 7.77). The Nagelkerke value for the three measures of sarcopenia was about 0.020 (2.0%) for incisional hernia development. Logistic regressions with the three measures of sarcopenia did not show any predictive value of the model (area under the curve (AUC) of 0.67 for incisional hernia; 0.69 for post‐operative complications).

Discussion

In this study, sarcopenia does not seem to be a risk factor for the development of an incisional hernia.
Paenibacillus amylolyticus 27C64 has a diverse set of carbohydrate-active enzymes and complete pectin deconstruction system
Authors: Keggi Christian , Doran-Peterson Joy
Published: October 2018

A draft genome of Paenibacillus amylolyticus 27C64 was assembled and a total of 314 putative CAZymes in 108 different families were identified. Comparison to well-studied polysaccharide-degrading organisms revealed that P. amylolyticus 27C64 has as many or more putative CAZymes than most of these organisms. Four different pectic substrates and xylan supported growth but cellulose was not utilized. Measurement of enzyme activities in culture supernatants revealed low levels of cellulase activity, high levels of xylanase activity, and pectinase activities that adapted to the specific polysaccharides provided. Relative expression levels of each putative pectinase in cells grown with and without three different pectic substrates were evaluated with RT-qPCR and distinct sets of genes upregulated in response to homogalacturonan, methylated homogalacturonan, and rhamnogalacturonan I were identified. It is also noted that this organism’s pectinolytic system differs from other well-studied systems and contains enzymes which are of value for further study.