bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of Acute Painful Episodes with Foetal Hemoglobin Level and Other Haematological Parameters in Sickle Cell Patients in Abuja Nigeria
Authors: Okeke O. Chinwe , Ukaejiofo O. Ernest , Obiageli E. Nnodu , Eyiuche D. Ezigbo , Chinedu C. Okeke
Published: August 2019

Introduction: Heterogeneity in sickle cell anaemia manifestations ranges from near asymptomatic cases to severe illness. 

Objective: This study determined the relationship between foetal haemoglobin F level, other haematological parameters and acute painful episode score of sickle cell disease patients in FCT Abuja Nigeria.

Methods: 60 Sickle cell patients were selected for the study. 20 severe crises, 20 non-severe crisis SS were enrolled in the study. Control group comprised 20 apparently healthy haemoglobin AA individuals. Data were analysed descriptively.

Results: Hb F level increased significantly in non-severe crisis sickle cell anaemia (7.12%± 3.6) and severe crisis (5.30%±2.3) groups, compared to the control group (0.32±1.8). This trend was also observed in RDW, MCHC and MCV. The mean Hb concentration and haematocrit (Hct) were significantly lower for both non- severe crisis and severe crisis SCA groups. There was no significant correlation between HbF and any of the haematological parameters in both non severe crisis and severe crisis groups. Patients with SCA had higher levels of HbF than matched controls. HbF had no correlation with any of the haematological parameters in both severe and non-severe SCA groups studied.

Conclusion: Further studies should focus on environmental factors contributing to this variability.
Physician’s Knowledge on X-ray Exposure from CT Scans in a Moroccan Hospital
Authors: Amaoui Bouchra , Kharras Abdennasser El , Semghouli Slimane
Published: August 2019

Background: Computed tomography (CT) is a major source of ionizing radiation exposure in medical diagnostic.  Patients more exposed related to radiation are supposed to be more susceptible to health risks.

Purpose: The aim of this study was to assess physician’s knowledge of radiation doses and potential health risks of radiation exposure from CT.

Materials and Methods: A standardized questionnaire was distributed to physicians. The questionnaire covered the demographic data of the prescriber, the frequency of referrals for CT scan examinations, the physicians’ knowledge of radiation doses, the potential health risks of radiation exposure from CT scan and training on patients’ radiation   protection. The data were analyzed using the Statistical Package for the Microsoft Office Excel 2007.

Results: A total of 72 physicians (55%) completed the questionnaire. Ninety nine percent of the practitioners’ prescribe CT examinations for patients during their exercises but only 10% of physicians use the guideline during CT prescriptions. Thirty eight percent of prescribers took into account the ratio benefit/risk related to x-rays during radiological exam prescription. While 4% of prescribers’ explained the risk related to x-rays to the patients during radiological exam prescription, 14% of physicians have correctly estimated the effective dose received during an abdomen pelvic scan compared to the dose of a standard chest x-ray radiograph in an adult.  Fifty four percent of doctors underestimated the lifetime risk of fatal cancer attributable to a single computed tomography scan of the abdomen pelvic and 8% of practitioners have received formal training on risks to patients from radiation exposure.

Conclusion: The present study showed the limited knowledge of radiation exposure for the Physicians. Recurrent training in advanced radiation protection of patients could lead to significant improvements in knowledge and practice of CT prescribers.
Knowledge, Attitude and Practice of Self-medication among Pharmacy Students in North Cyprus
Authors: Khamis Sarah , Sheqer Hasan , Arsoy Gunay
Published: August 2019

Aim: The aim of our study is to assess the attitude, knowledge and practice of self-medication among fifth year Pharmacy Students at Near East University in Northern Cyprus.

Study Design: A cross sectional study.

Place and Duration of Study: The study was conducted in faculty of pharmacy in Near East University in Northern Cyprus on 28 of December 2018.

Methodology: A 7- part self administered questionnaire was used among fifth year pharmacy students who were available during the study time.

Results: A total of 77 questionnaires were distributed to be filled by respondents, all of them were filled completely and collected. 88% of the participants in our study were in the prevalent age group of 22-26 years and most of these students were from Turkey (58.3%). 25.7% of students visited a physician when they had a disease, however 25% of them didn’t comply with physician’s prescription. Headache (16.8%) and common cold (14.0%) were the most frequently reported illness for which self-medication was taken. Analgesic medicines (37.4%), followed by vitamins (29.7%) and antibiotic (13.5%), were used commonly as self-medication. Nearly all of students 95.9% knew the meaning of OTC and prescription only drugs. About 30.7% of students medicated themselves because it isn’t a serious disease. The main source of information about self-medication for students was  the advice from pharmacist (29.7%). 26.8% of students  agreed that pharmacists are good source of information for minor medical problems, 18.2% agreed that self-medication is acceptable for pharmacy students however 4.1% accepted that self-medication is not acceptable at all and it would be harmful.

Conclusion: The practice of self-medication is prevalent amongst fifth year pharmacy students even with adequate knowledge and awareness about the consequences. Proactive pharmacist may contribute in management of minor illness and rationalized self-medication.
Localization and ER membrane insertion of parathyroid hormone‐related protein analyzed without effects of reporter proteins
Authors: Amaya Yoshihiro , Nakai Toshiki
Published: August 2019

Parathyroid hormone‐related protein (PTHrP) is transported to both the secretory pathway and the nucleus/nucleolus by its dual targeting signals, that is, an N‐terminal signal peptide and nuclear targeting signal. Curiously, reporter proteins such as enhanced green fluorescent protein strongly affect the localization of the fusion protein. Here, we report a novel methionine tag for 35S‐labelling added to the C‐terminus of its prepro‐form, which has no methionine and cysteine residue other than the initiation methionine that enables analyses of the molecular mechanism of its dual localization without the effects of the reporter proteins. Mutational analyses including insertion of a glycosylation site for the tagged PTHrP revealed that the evolutionarily conserved regions in the signal peptide and the pro‐region facilitate the redirection of ppPTHrP from the secretory pathway to the nuclear targeting pathway.
Modeling Elekta VersaHD using the Varian Eclipse treatment planning system for photon beams: A single‐institution experience
Authors: Zhang You , Le Anh H. , Tian Zhen , Iqbal Zohaib , Chiu Tsuicheng , Gu Xuejun , Pugachev Andrei , Reynolds Robert , Park Yang K. , Lin Mu‐Han , Stojadinovic Strahinja
Published: August 2019

The aim of this study was to report a single‐institution experience and commissioning data for Elekta VersaHD linear accelerators (LINACs) for photon beams in the Eclipse treatment planning system (TPS). Two VersaHD LINACs equipped with 160‐leaf collimators were commissioned. For each energy, the percent‐depth‐dose (PDD) curves, beam profiles, output factors, leaf transmission factors and dosimetric leaf gaps (DLGs) were acquired in accordance with the AAPM task group reports No. 45 and No. 106 and the vendor‐supplied documents. The measured data were imported into Eclipse TPS to build a VersaHD beam model. The model was validated by creating treatment plans spanning over the full‐spectrum of treatment sites and techniques used in our clinic. The quality assurance measurements were performed using MatriXX, ionization chamber, and radiochromic film. The DLG values were iteratively adjusted to optimize the agreement between planned and measured doses. Mobius, an independent LINAC logfile‐based quality assurance tool, was also commissioned both for routine intensity‐modulated radiation therapy (IMRT) QA and as a secondary check for the Eclipse VersaHD model. The Eclipse‐generated VersaHD model was in excellent agreement with the measured PDD curves and beam profiles. The measured leaf transmission factors were less than 0.5% for all energies. The model validation study yielded absolute point dose agreement between ionization chamber measurements and Eclipse within ±4% for all cases. The comparison between Mobius and Eclipse, and between Mobius and ionization chamber measurements lead to absolute point dose agreement within ±5%. The corresponding 3D dose distributions evaluated with 3%global/2mm gamma criteria resulted in larger than 90% passing rates for all plans. The Eclipse TPS can model VersaHD LINACs with clinically acceptable accuracy. The model validation study and comparisons with Mobius demonstrated that the modeling of VersaHD in Eclipse necessitates further improvement to provide dosimetric accuracy on par with Varian LINACs.
Numerical Simulation of an Industrial‐Scale Prototypical Steel Melt Tundish Considering Flow Control and Cleaning Strategies
Authors: Neumann Sebastian , Asad Amjad , Schwarze Rüdiger
Published: August 2019

Herein, the increase in the cleanliness of steel melt is researched using an industrial‐scale prototypical tundish. State‐of‐the‐art alumina‐coated, carbon‐bonded ceramic foam hybrid filters are used, which combine different filtration strategies for the removal of nonmetallic inclusions (NMI) in steel melts. Reactive cleaning reduces a high amount of inclusions by means of flotation because of carbon monoxide bubbles. Their formation is based on a reaction between the dissolved carbon from the filter and the oxygen of the steel melt. The direct deposition of NMI at the filter surfaces is called active filtration. Numerical simulations are performed to compare the performance of flow‐controlling applications inside the tundish and different filter developments (shape and position) to increase the cleanliness of steel melt. The continuous steel melt, the dispersed NMI as well as the carbon monoxide bubbles are calculated with an Eulerian–Lagrangian approach focusing on the inclusion removal by active filtration and reactive cleaning.
Substrate‐Controlled Divergent Synthesis of Enaminones and Pyrroles from Indolizines and Nitroso Compounds
Authors: González‐Soria María José , Alonso Francisco
Published: August 2019

It is imperative to learn new synthetic transformations to succeed in drug discovery and development. We report the substrate‐driven synthesis of β‐enaminones and N‐aryl pyrroles from indolizines and nitrosoarenes; aryl‐substituted indolizines lead to β‐enaminones in a regio‐ and diastereoselective manner, whereas alkyl‐substituted indolizines produce tetrasubstituted pyrroles. All products contain a pyridine unit, the second most abundant ring (after phenyl) in the FDA Orange Book. In both cases, the reactions proceed at room temperature without any catalyst. Moreover, both types of products can be obtained in one pot from commercial materials as well as at a gram scale. It is worthy of note that the regioselectivity of the β‐enaminones is inaccessible by the standard literature methods and their utility has been exemplified in the synthesis of diverse heterocycles. We have made every endeavor to put forward the corresponding reaction mechanisms based on thorough experimental work.

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One‐pot synthesis of octablock copolymers of high‐molecular weight via RAFT emulsion polymerization
Authors: Fang Jinwei , Wang Shengpeng , Luo Yingwu
Published: August 2019

Multiblock copolymers (mBCPs) could offer new opportunities to design new nanomaterials with multifunctions or enhanced properties in a cost‐effective way. However, it is still very challenging to obtain high degree of polymerization in each block of mBCPs with large block number using one‐pot synthesis via controlled radical polymerizations. This is due to the accumulation of the dead chains throughout the many step polymerization. In this work, we developed a new highly efficient strategy for preparing mBCPs with large block number using one‐pot reversible addition–fragmentation chain transfer (RAFT) emulsion polymerization, where every polymer block was formed by sequential addition of monomers. We achieved high block degree of polymerizations (~100 per block) for a model system of “octablock” polystyrene (PS) in just 2 hr per block. Experimentally measured molecular weights are in excellent agreement with theoretical predictions. The dead chains generated through the polymerization are negligible due to the low initiator concentration. Yet the polymerization rates are still very fast due to the heterogeneous advantages of emulsion polymerization. We have also applied this strategy to a series of mBCPs from diblock (PS176‐PnBA286)1 to octablock (PS176‐PnBA286)4 (PnBA for poly(n‐butyl acrylate)). The high degree of polymerization in our mBCPs ensures microphase separation even though PS/PnBA system is known for small
χ values. We have also found that the tensile properties of our mBCPs increase significantly with increased number of blocks. Our work reveals that the number of blocks is an important molecular variable for tuning the mechanical properties of block copolymers.
An AIEgen‐Peptide Conjugate as a Phototheranostic Agent for Phagosome‐Entrapped Bacteria
Authors: Qi Guobin , Hu Fang , Kenry  , Shi Leilei , Wu Min , Liu Bin
Published: August 2019

The detection and elimination of intracellular bacteria remain a major challenge. In this work, we report an aggregation‐induced emission (AIE) bioprobe that can detect bacterial infection and kill bacteria surviving inside macrophages through a dynamic process, notably specific molecular tailoring of the probe by caspase‐1 activation in infected macrophages and accumulation of the residue on phagosomes containing bacteria, leading to light‐up fluorescent signals. Moreover, the AIEgen can serve as a photosensitizer for generation of reactive oxygen species (ROS); and the average ROS indicator fluorescent signal intensity per unit area in the bacterial phagosomes is approximately 2.7‐fold higher than that in the cytoplasm. This, in turn, induces bacteria killing with high efficiency and minimal cytotoxicity towards macrophages. We envision that this specific light‐up bioprobe may provide a new approach for selective and sensitive detection and eradication of intracellular bacterial infections.
Surface modification of MWCNT and its influence on properties of paraffin/MWCNT nanocomposites as phase change material
Authors: Avid Arezoo , Jafari Seyed Hassan , Khonakdar Hossein Ali , Ghaffari Mehdi , Krause Beate , Pötschke Petra
Published: August 2019

Multiwalled carbon nanotubes (MWCNTs) were modified by an organo‐silane in order to improve their dispersion state and stability in paraffin wax. A family of paraffin‐based phase change material (PCM) composites filled with MWCNTs was prepared with different loadings (0, 0.1, 0.5, and 1 wt%) of pristine MWCNTs and organo‐silane modified MWCNTs (Si‐MWCNT). Structural analyses were performed by means of Fourier transform infrared (FTIR), scanning electron microscopy (SEM), and rheological studies using temperature sweeps. Moreover, phase change transition temperatures and heat of fusion as well as thermal and electrical conductivities of the developed PCM nanocomposites were determined. The SEM micrographs and FTIR absorption bands appearing at approximately 1038 and 1112 cm−1 confirmed the silane modification. Differential scanning calorimetery (DSC) results indicate that the presence of Si‐MWCNTs leads to slightly favorable enhancement in the energy storage capacity at the maximum loading. It was also shown that the thermal conductivity of the PCM nanocomposites, in both solid and liquid phases, increased with increasing the MWCNT content independent of the kind of MWCNTs by up to about 30% at the maximum loading of MWCNTs. In addition, the modification of MWCNTs made the samples completely electrically nonconductive, and the electrical surface resistivity of the PCMs containing pristine MWCNTs decreased with increasing MWCNTs loading. Furthermore, the rheological assessment under consecutive cyclic phase change demonstrated that the samples containing modified MWCNTs are more stable compared to the PCM containing pristine MWCNTs. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48428.
Developing conductive immiscible polystyrene/polypropylene blends with a percolated conducting polyaniline/polyamide filler by tuning its specific interactions with the styrene‐based triblock compatibilizer grafted with maleic anhydride
Authors: Bharati Avanish , Hejmady Prakhyat , Van der Donck Tom , Seo Jin Won , Cardinaels Ruth , Moldenaers Paula
Published: August 2019

An approach to induce conductivity in immiscible polystyrene/polypropylene (PS/PP) blends is described using a percolated conducting polyaniline/polyamide (PANI/PA) filler combined with a polystyrene‐block‐poly(ethylene‐ran‐butylene)‐block‐polystyrene‐graft‐maleic anhydride compatibilizer. The approach is based on the ability of the compatibilizer to concomitantly stabilize the cocontinuous morphology and to improve the state of dispersion of the PANI/PA filler. Selective localization of PANI/PA in the PS phase with improved filler dispersion is achieved with the optimal master batch (MB) preparation technique followed by its optimized sequence addition to the blend components. This results in an increase in the dc conductivity by six decades as compared with that of the neat compatibilized blend at an effective 4.8‐wt % PANI concentration. An investigation of the effect of functionality and concentration of the filler and the compatibilizer on the filler connectivity in the blend is performed. The prevailing specific interactions are analyzed by Fourier transform infrared spectroscopy and thermogravimetric analysis of the MBs. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48433.
Effect of ionic liquid on the structure and desalination performance of PVDF‐PTFE electrospun membrane
Authors: Li Jun , Ren Long‐Fei , Shao Jiahui , Adeel Mister , Tu Yonghui , Ma Zhongbao , He Yiliang
Published: August 2019

The relatively large pore size of electrospun membranes might limit their application for direct contact membrane distillation (DCMD). Incorporation of ionic liquid is a potential approach to decrease the pore size of electrospun membranes, which was attributed to the increased conductivity of electrospinning solution. In this study, a novel nanofibrous membrane based on the blends of poly(vinylidene fluoride) (PVDF), polytetrafluoroethylene (PTFE) and ionic liquid (BMIMPF6) was fabricated and applied for the DCMD. The effects of the BMIMPF6 on the morphology, pore size and DCMD performance of the PVDF‐PTFE nanofibrous membrane were investigated. Compared with neat (PVDF‐PTFE) membranes (average pore size: 0.93 μm), the incorporation of BMIMPF6 resulted in a smaller mean pore diameter (0.58 μm). The liquid entry pressure value of the modified composite membrane also increased from 62.75 kPa (neat) to 83 kPa, due to the decreased pore size. The composite membrane exhibited a longer lifespan (about 26 h) than neat membrane during long‐term DCMD process, which makes this composite membrane a promising candidate for DCMD application. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48467.
Structural diversity of adipokinetic hormones in the hyperdiverse coleopteran Cucujiformia
Authors: Gäde Gerd , Šimek Petr , Marco Heather G.
Published: August 2019

Seventeen species of the coleopteran series Cucujiformia are investigated for the presence and sequence of putative adipokinetic hormones (AKHs). Cucujiformia includes species from the major superfamilies, that is, Chrysomeloidea, Curculionoidea, Cucujoidea, and Tenebrionoidea. The clade Phytophaga in which the Chrysomeloidea and Curculionoidea reside, harbor very detrimental species for agriculture and forestry. Thus, this study aims not only to demonstrate the structural biodiversity of AKHs in these beetle species and possible evolutionary trends but also to determine whether the AKHs from harmful pest species can be used as lead substances for a future putative insecticide that is harmless to beneficial insects. Sequence analysis of AKHs is achieved by liquid chromatography coupled to mass spectrometry. Most of the investigated species contain AKH octapeptides in their corpora cardiaca, although previously published work also found a few decapeptides, which we comment on. The signature and sole AKH in cerambycidae Chrysomeloidea and Curculionoidea is Peram‐CAH‐I (pEVNFSPNW amide), which is also found in the majority of chrysomelidae Chrysomeloidea and in the one investigated species of Cucujoidea albeit in a few cases associated with a second AKH which can be either Peram‐CAH‐II (pELTFTPNW amide), Emppe‐AKH (pEVNFTPNW amide), or Micvi‐CC (pEINFTPNW amide). The most often encountered AKH in Tenebrionoidea, family Meloidae as well as family Tenebrionidae, is Tenmo‐HrTH (pELNFSPNW amide) followed by Pyrap‐AKH (pELNFTPNW amide) and a Tenmo‐HrTH extended decapeptide (in Meloidae). Finally, we examine AKH sequences from 43 species of cucujiform beetles, including the superfamily Coccinelloidea for a possible lead compound for producing a cucujiform‐specific pesticide.
Stability and change in social interaction style of children with autism spectrum disorder: A 4‐year follow‐up study
Authors: Scheeren Anke M. , Koot Hans M. , Begeer Sander
Published: August 2019

Children with autism spectrum disorder (ASD) show atypical social behavior but vary in their social interaction style (SIS), ranging from social aloofness to awkward social approaches. In a 4‐year follow‐up study, we examined longitudinal stability and change of SIS in children and adolescents with ASD and a normal intellectual ability (n = 55; mean age Time 1: 13 years; mean age Time 2: 17 years). Children's SIS was assessed with a parent questionnaire, the Wing Subtypes Questionnaire. As expected, most participants (69%) showed SIS stability across the 4‐year interval. Some participants (18%) shifted to a more typical or more active (but odd) SIS, while others (13%) shifted to a less typical or less active (but odd) SIS. A decrease in ASD symptoms predicted a shift toward a more typical or active SIS, but children's age and receptive verbal ability did not. SISs may be a meaningful way to create ASD subgroups and thus offer a promising research venue to further disentangle the heterogeneous autism spectrum. Autism Res 2020, 13: 74–81. © 2019 The Authors. Autism Research published by International Society for Autism Research published by Wiley Periodicals, Inc.

Lay Summary

People with autism spectrum disorder (ASD) demonstrate different social interaction styles (SIS), ranging from social aloofness to awkward social approaches. We examined if and how SIS changes across a 4‐year period in 55 children and adolescents with ASD (mean age Time 1 = 13 years; mean age Time 2 = 17 years). Most children (69%) showed the same SIS at both time points, indicating that SIS might be a relatively stable trait across adolescence.
Molecular Structure of Binary Chromium(III)–DNA Adducts
Authors: Brown Silas , Lockart Molly M. , Thomas C. Sumner , Bowman Michael K. , Woski Stephen A. , Vincent John B.
Published: August 2019

Chromium(VI) is a carcinogen and mutagen, and its mechanisms of action are proposed to involve binding of its reduction product, chromium(III), to DNA. The manner in which chromium(III) binds DNA has not been established, particularly at a molecular level. Analysis of oligonucleotide duplex DNAs by NMR, EPR, and IR spectroscopies in the presence of chromium(III) allows the elucidation of the Cr binding site. The metal centers were found to interact exclusively with guanine N7 positions. No evidence of chromium interactions with other bases or backbone phosphates nor of Cr forming intra‐strand crosslinks between neighboring guanine residues was observed.
Risk factors for infective endocarditis following transcatheter pulmonary valve replacement in patients with congenital heart disease
Authors: Sadeghi Soraya , Wadia Subeer , Lluri Gentian , Tarabay Jana , Fernando Anisha , Salem Morris , Sinha Sanjay , Levi Daniel S. , Aboulhosn Jamil
Published: August 2019

Objectives

We sought to delineate the risk factors for infective endocarditis (IE) in patients undergoing transcatheter pulmonary valve replacement (TCPVR).

Background

Despite the therapeutic benefits of TCPVR for treatment of dysfunctional right ventricular outflow tracts, IE is a major complication of the approach. Specific hemodynamic gradients and patient immune status as predisposing factors for IE are largely unexplored.

Methods

We performed a retrospective review of patients who had undergone TCPVR at UCLA between October 2010 and October 2017. Cases of IE were diagnosed based on the modified Duke criteria.

Results

Two hundred and thirty‐five cases of TCPVR were performed with a mean follow‐up of 2.6 years (range 0.0–8.0 years). Sixteen distinct IE events developed in 13 patients (Melody™ n = 12, SAPIEN n = 1), with a median time from implant to IE of 3.3 years (range 2.0–7.2 years). Univariate Cox regression showed that immunocompromised status was significantly associated with the development of IE hazard ratios (HR 5.43 [1.80–16.4], p = .003). Kaplan–Meier curves show that the 5‐year freedom from IE among immunocompetent patients was 87% (95% CI 78–96%) versus 64% (95% CI 39–89%) among immunocompromised patients (log‐rank p = .02). Postimplant right ventricular systolic pressure was higher among immunocompromised patients (p = .03). The risk of IE post‐TCPVR in immunocompromised patients with residual pulmonary stenosis was 43%.

Conclusions

Among the risk factors examined in this study, immunocompromised status was the most significant predictor of IE development post‐TCPVR. Patients with the lowest risk of IE are those with competent immune systems, without a history of IE, and with minimal residual pulmonary valve gradients post‐TCPVR.
Initial experience with vascular plug devices for mechanical thrombectomy in symptomatic neonates and infants
Authors: McGovern Eimear , Qureshi Athar M. , Goldstein Bryan H.
Published: August 2019

Objectives

To describe a novel technique for mechanical thrombectomy (MT) in young children.

Background

Acute thrombosis in children may be a cause of significant morbidity or mortality. MT options in children are limited due to patient and vessel size, prompting consideration of innovative approaches.

Methods

Two‐center review of children with symptomatic non‐cerebral thrombotic vessel occlusion. A novel approach to MT was performed using a deployed but unreleased amplatzer vascular plug (AVP) to “scrape” the target vessel in retrograde fashion, thereby harvesting the thrombus via the access sheath.

Results

AVP‐MT was performed in four patients at a median age of 2 months (range: 1 day‐11 months) and median weight of 5.6 kg (1.8–10.9). In two cases, AVP‐MT was performed in isolation in neonates on cervical extracorporeal membrane oxygenation (ECMO) support with cannula‐associated obstructive aortic and brachiocephalic thrombus. AVP‐MT was also performed as adjunctive therapy in a patient with single ventricle physiology and pulmonary artery thrombosis and in an infant with mitral valve endocarditis and femoral arterial thromboembolism. In all cases, AVP‐MT was used to successfully remove thrombus from the target vessel and restore arterial flow, without procedural complications. Recurrent thrombosis occurred in both neonates, due to persistence of the ECMO cannula, with subsequent mortality. The other children were free of recurrent thrombus at 2 and 34 months.

Conclusions

Acute relief of symptomatic thrombosis may be achieved using AVP‐MT in small children, although thrombosis frequently recurs, and clinical prognosis may remain poor. This strategy should be considered when alternative MT treatment options are not applicable.
N‐Heterocyclic Olefins as Electron Donors in Combination with Triarylborane Acceptors: Synthesis, Optical and Electronic Properties of D–π–A Compounds
Authors: He Jiang , Rauch Florian , Friedrich Alexandra , Sieh Daniel , Ribbeck Tatjana , Krummenacher Ivo , Braunschweig Holger , Finze Maik , Marder Todd B.
Published: August 2019

N‐heterocyclic olefins (NHOs), relatives of N‐heterocyclic carbenes (NHCs), exhibit high nucleophilicity and soft Lewis basic character. To investigate their π‐electron donating ability, NHOs were attached to triarylborane π‐acceptors (A) giving donor (D)–π–A compounds 1–3. In addition, an enamine π‐donor analogue (4) was synthesized for comparison. UV–visible absorption studies show a larger red shift for the NHO‐containing boranes than for the enamine analogue, a relative of cyclic (alkyl)(amino) carbenes (CAACs). Solvent‐dependent emission studies indicate that 1–4 have moderate intramolecular charge‐transfer (ICT) behavior. Electrochemical investigations reveal that the NHO‐containing boranes have extremely low reversible oxidation potentials (e.g., for 3,
=−0.40 V vs. ferrocene/ferrocenium, Fc/Fc+, in THF). Time‐dependent (TD) DFT calculations show that the HOMOs of 1–3 are much more destabilized than that of the enamine‐containing 4, which confirms the stronger donating ability of NHOs.
Reversible Wide‐Range Tuneable Luminescence of a Dual‐Stimuli‐ Responsive Silver Cluster‐Assembled Material
Authors: Ma Xiao‐Hong , Wang Jia‐Yin , Guo Jun‐Jie , Wang Zhao‐Yang , Zang Shuang‐Quan
Published: August 2019

Summary of main observation and conclusion

Silver cluster‐assembled materials (SCAMs) are emerging multi‐functional materials and have attracted great attention recently. In this work, we have prepared a new SCAM of {[Ag18(StBu)10(CF3COO)2(PhPO3)(PhPO3H)4(bpy‐NH2)2]∙(PhPO3H2)}n (denoted as Ag18bpy‐NH2), by a facile one‐pot method. Ag18bpy‐NH2 adopts a chain‐like structure made of Ag18 clusters bridged by bipyridyl linkers. Ag18bpy‐NH2 exhibits reversible luminescent mechanochromism upon mechanical stimulation and solvent treatment. Moreover, it also displays luminescent thermochromism with a linear relationship of the temperature to the intensity ratio of the dual emissions over a wide temperature range of 83 to 303 K. This work might provide new insights into the assembly of multifunctional stimuli‐responsive SCAMs.
Combining Zinc Phthalocyanines, Oligo(p‐Phenylenevinylenes), and Fullerenes to Impact Reorganization Energies and Attenuation Factors
Authors: Krug Marcel , Stangel Christina , Zieleniewska Anna , Clark Timothy , Torres Tomás , Coutsolelos Athanassios G. , Guldi Dirk M.
Published: August 2019

A study on electron transfer in three electron donor‐acceptor complexes is reported. These architectures consist of a zinc phthalocyanine (ZnPc) as the excited‐state electron donor and a fullerene (C60) as the ground‐state electron acceptor. These complexes are brought together by axial coordination at ZnPc. The key variable in our design is the length of the molecular spacer, namely, oligo‐p‐phenylenevinylenes. The lack of appreciable ground‐state interactions is in accordance with strong excited‐state interactions, as inferred from the quenching of ZnPc centered fluorescence and the presence of a short‐lived fluorescence component. Full‐fledged femtosecond and nanosecond transient absorption spectroscopy assays corroborated that the ZnPc ⋅ +‐C60 ⋅ − charge‐separated state formation comes at the expense of excited‐state interactions following ZnPc photoexcitation. At a first glance, the ZnPc ⋅ +‐C60 ⋅ − charge‐separated state lifetime increased from 0.4 to 86.6 ns as the electron donor‐acceptor separation increased from 8.8 to 29.1 Å. A closer look at the kinetics revealed that the changes in charge‐separated state lifetime are tied to a decrease in the electronic coupling element from 132 to 1.2 cm−1, an increase in the reorganization energy of charge transfer from 0.43 to 0.63 eV, and a large attenuation factor of 0.27 Å−1.
Analysis of Drosophila nervous system development following an early, brief exposure to ethanol
Authors: Scepanovic Gordana , Stewart Bryan A.
Published: August 2019

The effects of ethanol on neural function and development have been studied extensively, motivated in part by the addictive properties of alcohol and the neurodevelopmental deficits that arise in children with fetal alcohol spectrum disorder (FASD). Absent from this research area is a genetically tractable system to study the effects of early ethanol exposure on later neurodevelopmental and behavioral phenotypes. Here, we used embryos of the fruit fly, Drosophila melanogaster, as a model system to investigate the neuronal defects that arise after an early exposure to ethanol. We found several disruptions of neural development and morphology following a brief ethanol exposure during embryogenesis and subsequent changes in larval behavior. Altogether, this study establishes a new system to examine the effects of alcohol exposure in embryos and the potential to conduct large‐scale genetics screens to uncover novel factors that sensitize or protect neurons to the effects of alcohol.
Identification of specific markers for amphetamines synthesized from glycidic acid pre‐precursors and retrospective search in German profiling database
Authors: Hauser Frank M. , Pütz Michael , Rößler Thorsten , Hulshof Janneke W.
Published: August 2019

The pre‐precursor market and the clandestine production of amphetamine‐type stimulants (ATS) has become more diverse in recent years. Besides α‐phenylacetoacetonitrile (APAAN) and α‐phenylacetoacetamide (APAA), glycidic acid derivatives and methyl α‐phenylacetoacetate (MAPA) are gaining importance. This conclusion is based on seizure data of police and customs. However, analytical data are needed to confirm and quantify the actual prevalence of new pre‐precursors by elucidating the percentage of seized ATS that have been produced from them. A recent study showed that APAAN use is currently declining, which supports the view that new pre‐precursors are being used. In this study, several conversion procedures using different batches of glycidic acid derivatives and a complete Leuckart reaction to produce amphetamine were carried out. The resulting organic phases were analyzed using gas chromatography − mass spectrometry to identify possible marker compounds. Three marker compounds were discovered and characterized using mass spectra and nuclear magnetic resonance spectroscopy. They were identified as phenyl‐1‐propanone, N‐(1‐phenylpropyl)formamide and 1‐phenylpropan‐1‐amine. Their prevalence was investigated by searching the markers in an amphetamine impurity profiling database to determine to what extent they occurred in amphetamine samples from recent years. Data from the central German amphetamine profiling database of more than 250 cases were used for this purpose. The yearly occurrence of the three glycidate marker compounds was determined going back as far as 2009, revealing an increasing trend from 2016 on. This article presents experimental proof that APAAN is currently being replaced by other pre‐precursors, such as glycidic acid derivatives.
Joint estimation of growth and survival from mark–recapture data to improve estimates of senescence in wild populations
Authors: Reinke Beth A. , Hoekstra Luke , Bronikowski Anne M. , Janzen Fredric J. , Miller David
Published: August 2019

Understanding age‐dependent patterns of survival is fundamental to predicting population dynamics, understanding selective pressures, and estimating rates of senescence. However, quantifying age‐specific survival in wild populations poses significant logistical and statistical challenges. Recent work has helped to alleviate these constraints by demonstrating that age‐specific survival can be estimated using mark–recapture data even when age is unknown for all or some individuals. However, previous approaches do not incorporate auxiliary information that can improve age estimates of individuals. We introduce a survival estimator that combines a von Bertalanffy growth model, age‐specific hazard functions, and a Cormack‐Jolly‐Seber mark–recapture model into a single hierarchical framework. This approach allows us to obtain information about age and its uncertainty based on size and growth for individuals of unknown age when estimating age‐specific survival. Using both simulated and real‐world data for two painted turtle (Chrysemys picta) populations, we demonstrate that this additional information substantially reduces the bias of age‐specific hazard rates, which allows for the testing of hypotheses related to aging. Estimating patterns of senescence is just one practical application of jointly estimating survival and growth; other applications include obtaining better estimates of the timing of recruitment and improved understanding of life‐history trade‐offs between growth and survival.
A Return to the Origin of the EMGS: Rejuvenating the Quest for Human Germ Cell Mutagens and Determining the Risk to Future Generations
Authors: Marchetti Francesco , Douglas George R. , Yauk Carole L.
Published: August 2019

Fifty years ago, the Environmental Mutagen Society (now Environmental Mutagenesis and Genomics Society) was founded with a laser‐focus on germ cell mutagenesis and the protection of “our most vital assets”—the sperm and egg genomes. Yet, five decades on, despite the fact that many agents have been demonstrated to induce inherited changes in the offspring of exposed laboratory rodents, there is no consensus on whether human germ cell mutagens exist. We argue that it is time to reevaluate the available data and conclude that we already have evidence for the existence of environmental exposures that impact human germ cells. What is missing are definite data to demonstrate a significant increase in de novo mutations in the offspring of exposed parents. We believe that with over two decades of research advancing knowledge and technologies in genomics, we are at the cusp of generating data to conclusively show that environmental exposures cause heritable de novo changes in the human offspring. We call on the research community to harness our technologies, synergize our efforts, and return to our Founders' original focus. The next 50 years must involve collaborative work between clinicians, epidemiologists, genetic toxicologists, genomics experts and bioinformaticians to precisely define how environmental exposures impact germ cell genomes. It is time for the research and regulatory communities to prepare to interpret the coming outpouring of data and develop a framework for managing, communicating and mitigating the risk of exposure to human germ cell mutagens. Environ. Mol. Mutagen. 61:42–54, 2020. © 2019 Her Majesty the Queen in Right of Canada
The Synergy of Dilute Pd and Surface Oxygen Species for Methane Upgrading on Au3Pd(111)
Authors: Do Quan K. , Tran Hung-Vu , Wang Shengguang , Grabow Lars C.
Published: August 2019

The grandest challenge in the direct upgrade of methane to useful chemicals is finding a catalyst that is active for the difficult C—H bond scission yet selective such that not all of the C—H bonds break to form coke or CO2. The Au3Pd(111) surface is studied for methane activation, particularly due to its surface geometry containing a single Pd atom fully surrounded by Au atoms. Through density functional theory (DFT) calculations, the nonoxidative and oxidative mechanisms for methane activation are examined. In the nonoxidative mechanism, the initial C—H bond scission on Au3Pd(111) resembles that of Pd(111), but the subsequent dehydrogenation steps are more difficult than the first, mimicking pure Au(111). In the oxidative mechanism, the dilute Pd atom in Au3Pd(111) draws oxygenated adsorbates to the weakly binding Au surface to assist in the activation of methane. In both cases, Au3Pd(111) merges the activity of pure Pd(111) and the selectivity of pure Au(111), indicating the promise of isolated reactive metals as a potential catalyst for the upgrade of methane and other dehydrogenation processes.
Estimating the period prevalence of non‐convulsive status epilepticus among comatose adults at the University Teaching Hospital in Lusaka, Zambia
Authors: Buback Clayton T. , Siddiqi Omar K. , Titima Innocent , Selioutski Olga , Birbeck Gretchen L.
Published: August 2019

Objective

In Western settings, non‐convulsive status epilepticus (NCSE) and non‐convulsive seizures (NCSz) are associated with high mortality. In comatose patients, interictal epileptiform discharges (IEDs) identified on routine electroencephalogram (EEG) are predictive of NCSE/NCS. Little is known regarding the prevalence, causes, or outcomes of NCSE/NCSz in sub‐Saharan Africa (SSA). We sought to investigate the prevalence of IEDs and NCSE/NCSz at a single teaching institution in SSA.

Methods

From October 3, 2017, to May 21, 2018, adult inpatients on the internal medicine service at Zambia's University Teaching Hospital (UTH) with a Glasgow Coma Score (GCS) of ≤10 were identified, excluding patients with mechanical ventilation or open head wounds. Signed consent by a proxy was required for enrollment and 30‐minute EEG. Chart abstractions provided coma duration, presence/absence of clinical seizures during/prior to admission, history of epilepsy, and presumed coma etiology. A structured neurological examination was completed. Patients were followed to discharge or death. Risk factors for IEDs were evaluated.

Results

Of 392 eligible patients, 250 had EEGs. EEGs were not completed on eligible patients due to death (74), improved GCS (37), transfer within UTH (25), or lack of proxy (6). NCSE occurred in 22 of 250 (8.8%), NCSz in 3 of 250 (1.2%), and IEDs in 46 of 250 (18.4%) patients. Of the 250, 197 (78.8%) died. No specific risk factors for IEDs were identified.

Significance

If the association between IEDs and NCSE among monitored populations in developed settings holds true for SSA, a projected 17%‐21% of comatose African adults have NCSE. No clinical characteristics identified those at risk.
Effects of long soil surface residence times on apparent cosmogenic nuclide denudation rates and burial ages in the Cradle of Humankind, South Africa
Authors: Makhubela T.V. , Kramers J.D. , Scherler D. , Wittmann H. , Dirks P.H.G.M. , Winkler S.R.
Published: August 2019

In situ cosmogenic nuclides are an important tool for quantifying landscape evolution and dating fossil‐bearing deposits in the Cradle of Humankind (CoH), South Africa. This technique mainly employs cosmogenic 10‐Beryllium (10Be) in river sediments to estimate denudation rates and the ratio of 26‐Aluminium (26Al) to 10Be (26Al/10Be), to constrain ages of sediment burial. Here, we use 10Be and 26Al concentrations in bedrock and soil above the Rising Star Cave (the discovery site of Homo naledi) to constrain the denudation rate and the exposure history of soil on the surface. Apparent 10Be‐derived denudation rates obtained from pebble‐ to cobble‐sized clasts and coarse‐sand in soil (on average 3.59 ± 0.27 m/Ma and 3.05 ± 0.25 m/Ma, respectively) are 2‐3 times lower than the bedrock denudation rates (on average 9.46 ± 0.68 m/Ma). In addition, soil samples yield an average 26Al/10Be ratio (5.12 ± 0.27) that is significantly lower than the surface production ratio of 6.75, which suggests complex exposure histories. These results are consistent with prolonged surface residence of up to 1.5 Ma in vertically mixed soils that are up to 3 m thick. We conclude that the 10Be concentrations accumulated in soils during the long near‐surface residence times can potentially cause underestimation of single‐nuclide (10Be) catchment‐wide denudation rates in the CoH. Further, burial ages of cave sediment samples that consist of an amalgamation of sand‐size quartz grains could be overestimated if a pre‐burial 26Al/10Be ratio calculated from the surface production is assumed. © 2019 John Wiley & Sons, Ltd.
A novel high temperature electrical storage heater using an inorganic salt based composite phase change material
Authors: Li Chuan , Li Qi , Zhao Yanqi , Jia Yixuan , Ding Yufeng , Jin Yi , Weng Likui , Ding Yulong
Published: August 2019

We have studied a high temperature storage heater containing an inorganic salt based composite phase change material (CPCM) for electrical load shift and operation cost reduction. The storage heater consists of CPCM modules with embedded electrical elements for charging at off‐peak hours and flow channels for discharging the stored heat in a controlled manner when needed. The flow channels are for heat transfer fluid (HTF, air in this work) to exchange heat with the CPCM modules and transport the heat to the heating space. A series of experiments are carried out to study the charging and discharging behavior of the storage heater. The effects of the flow channel arrangements between the CPCM modules, and the heating element arrangements inside the heater are studied. A mathematical model is also developed to investigate the performance of the storage heater with a focus on the performance comparison of the storage heater filled with the CPCM and that with the ferric oxide bricks (the conventional sensible heat storage material), and the evaluation of temperature control strategy for the CPCM based storage heater. The results show that a charge of 8 hours of the storage heater during the off‐peak period is sufficient to supply heat for the whole day under the conditions of this work. The flow channel arrangements have significant influences on the storage heater performance in terms of temperature distribution of the CPCM modules and HTF outlet temperature, and the efficiencies of the charging and discharging processes. An interlaced arrangement of CPCM modules in the heater can effectively reduce the temperature swing (eg, between 21.7°C and 22.5°C over a day) and hence improve the room thermal comfort level. The results also show that the CPCM based storage heater gives a superior performance than the ferric oxide based storage heater. Given the storage volume, the power rating, and the amount of stored heat, the mass of the ferric oxide based storage heater is more than 1.6 times that of the CPCM based storage heater. Given the mass and power rating, the heat storage capacity of the CPCM based heater is nearly 68% higher than that of the ferric oxide based storage heater. It is also found that the heat storage performance could be enhanced through a temperature control strategy with the temperature measurement located 15 mm away from the heating elements, for which the heating elements only need two start‐stops over the 8‐hour charging period.