bluuebunny/crossref_metadata_2025 huggingface dataset:
Human umbilical cord mesenchymal stem cell‐derived extracellular vesicles: A novel therapeutic paradigm
Authors: Abbaszadeh Hossein , Ghorbani Farzaneh , Derakhshani Mehdi , Movassaghpour Aliakbar , Yousefi Mehdi
Published: June 2019

Mesenchymal stem cells (MSCs) have been revealed to hold great potential for the development of new treatment approaches for various diseases. However, the clinical use of these cells is limited due to their tumorigenic effects. The therapeutic benefits of MSCs are largely dependent on paracrine factors including extracellular vesicles (EVs). EVs are nano‐sized bilayer membrane structures containing lipids, microRNAs and proteins which play key roles in cell‐to‐cell communications. Because of their lower immunogenicity, tumorigenicity, and easier management, EVs have emerged as a new promising alternative to whole‐cell therapy. Therefore, this paper reviews current preclinical studies on the use of EVs derived from human umbilical cord MSCs (hucMSCs) as a therapeutic approach in treatment of several diseases including neurological, cardiovascular, liver, kidney, and bone diseases as well as the cutaneous wound, inflammatory bowel disease, cancers, infertility, and other disorders.
Cyclic fatigue resistance of rotary NiTi instruments produced with four different manufacturing methods
Authors: Keskin Neslihan B. , Inan Uğur
Published: June 2019

The aim of this study was to compare the cyclic fatigue resistance of rotary NiTi files, produced with four different manufacturing methods on specially designed dynamic models that simulated clinical conditions. In this study, 120 files, consisting of 30 files for Typhoon, ProTaper Next, RaCe, and Twisted Files nickel titanium rotary systems were used. The 30 files of each group were divided into three subgroups to be used in artificial canals with a 60° angle of curvature and radii of curvature of 2, 5, and 8 mm (n = 10). All files were rotated in the artificial canals until fracture occurred and the number of cycles to fracture was calculated. The data were analyzed using one‐ and two‐way analyses of variance and Tamhane multiple comparison tests. In all three groups, Typhoon instruments had the highest number of cycles to failure than the RaCe, ProTaper Next, and Twisted Files instruments, and the difference statistically significant (p < .05). There were no significant differences between the RaCe, ProTaper Next, and Twisted Files groups (p > .05). The CM wire Typhoon system was significantly more resistant to cyclic fatigue compared to the other file systems in all three artificial canals. When the fracture resistance of an instrument in three different artificial canals was compared, the mean NCFs decreased as the radius of the curvature of the canal decreased from 8 to 2 mm. Manufacturing method is one of the most important factors on cyclic fatigue resistance, also the radius of curvature effects the cyclic fatigue.
Taxonomic significance of caryopsis in subfamily Panicoideae (Poaceae) using scanning electron microscopy and light microscopy
Authors: Usma Anwer , Ahmad Mushtaq , Zafar Muhammad , Ali Muhammad I. , Kilic Omer , Ozdemir Fethi A. , Sultana Shazia , Nazir Abdul , Anjum Farida , Kalsoom Nomana
Published: June 2019

In recent study, 13 taxa of subfamily Panicoideae were investigated for morphological characterization of caryopsis. Light microscope (LM) and scanning electron microscope (SEM) were utilized to study macro‐ and micro‐morphological caryopsis features respectively. Caryopsis size in studied taxa was recorded as 1.5–10 mm long and 1–4 mm wide. Caryopsis color was brown, green, yellow, and whitish‐brown. Caryopsis shape studied was obovate, elliptic, linear oblate, and round shallowly obtriangular. Hilum position is grooved and depressed. Caryopsis compression type was lateral and dorsiventral. Major variations among studied taxa were observed in terms of caryopsis surface pattern and epicuticular projection types. Six types of caryopsis surface pattern were observed viz. scabrate, rugose, striate, reticulate, papillate, and scabridulous. Structures such as silica cells, bulges, spines, prickles, granules, and bicellular microhair were studied as epicuticular projections. Major variations were observed among Cenchrus pennisetiformis and Cenchrus ciliaris as both has entirely two different types of surface patterns and epicuticular projections. Anticlinal wall thickness and pattern as well as periclinal wall texture and level were investigated. The present research work emphasized on caryopsis characterization of subfamily Panicoideae and it is recommended to establish phylogeny within subfamily Panicoideae and with other subfamilies of Poaceae.
The interplay between depression and tuberculosis
Authors: Zhang Kehong , Wang Xin , Tu Jie , Rong Han , Werz Oliver , Chen Xinchun
Published: June 2019

Depression is a major mental health condition and is expected be the most debilitating and widespread health disorder by 2030. Tuberculosis (TB) is also a leading cause of morbidity and mortality worldwide and interestingly, is a common comorbidity of depression. As such, much attention has been paid to the association between these 2 pathologies. Based on clinical reports, the association between TB and depression seems to be bidirectional, with a substantial overlap in symptoms between the 2 conditions. TB infection or reactivation may precipitate depression, likely as a consequence of the host's inflammatory response and/or dysregulation of the hypothalamic–pituitary–adrenal axis. Nevertheless, few studies have considered whether patients with depression are at a higher risk for TB. In this review, we discuss the hypotheses on the association between depression and TB, highlighting the immuno-inflammatory response and lipid metabolism as potential mechanisms. Improving our understanding of the interplay between these 2 disorders should help guide TB clinical care and prevention both in patients with comorbid depression and in the general population.
N‐carbamoylglutamate‐responsive carbamoyl phosphate synthetase 1 (CPS1) deficiency: A patient with a novel CPS1 mutation and an experimental study on the mutation's effects
Authors: Yap Sufin , Gougeard Nadine , Hart Anthony R. , Barcelona Belén , Rubio Vicente
Published: July 2019

N‐carbamoyl‐l‐glutamate (NCG), the N‐acetyl‐l‐glutamate analogue used to treat N‐acetylglutamate synthase deficiency, has been proposed as potential therapy of carbamoyl phosphate synthetase 1 deficiency (CPS1D). Previous findings in five CPS1D patients suggest that NCG‐responsiveness could be mutation‐specific. We report on a patient with CPS1D, homozygous for the novel p.(Pro1211Arg) CPS1 mutation, who presented at 9 days of life with hyperammonemic coma which was successfully treated with emergency measures. He remained metabolically stable on merely oral NCG, arginine, and modest protein restriction. Ammonia scavengers were only added after poor dietary compliance following solid food intake at age 1 year. The patient received a liver transplantation at 3.9 years of age, having normal cognitive, motor, and quality of life scores despite repeated but successfully treated episodes of hyperammonemia. Studies using recombinantly produced mutant CPS1 confirmed the partial nature of the CPS1D triggered by the p.(Pro1211Arg) mutation. This mutation decreased the solubility and yield of CPS1 as expected for increased tendency to misfold, and reduced the thermal stability, maximum specific activity (Vmax; ~2‐fold reduction), and apparent affinity (~5‐fold reduction) for ATP of the purified enzyme. By increasing the saturation of the NAG site in vivo, NCG could stabilize CPS1 and minimize the decrease in the effective affinity of the enzyme for ATP. These observations, together with prior experience, support the ascertainment of clinical responsiveness to NCG in CPS1 deficient patients, particularly when decreased stability or lowered affinity for NAG of the mutant enzyme are suspected or proven.
Burden and trends of arrhythmias in hypertrophic cardiomyopathy and its impact of mortality and resource utilization
Authors: Tripathi Byomesh , Khan Safi , Arora Shilpkumar , Kumar Varun , Naraparaju Vamsidhar , Lahewala Sopan , Sharma Purnima , Atti Varunsiri , Jain Varun , Shah Mahek , Patel Brijesh , Ram Pradhum , Deshmukh Abhishek
Published: June 2019

Background

Hypertrophic cardiomyopathy (HCM) accounts for significant morbidity and mortality worldwide. Arrhythmias are considered the main cause of mortality, however, there is paucity of data relating to trends of arrhythmia and associated outcomes in HCM patients.

Methods

Nationwide Inpatient Sample from 2003 to 2014 was analyzed. HCM related hospitalizations were identified using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD9‐CM) code 425.1 and 425.11 in all diagnosis fields.

Results

Overall, there was an increase in number of hospitalizations related to arrhythmias among HCM patients from 7784 in 2003 to 8380 in 2014 (relative increase 10.5%, P < 0.001). The increase was most significant in patients ≥ 80 years and those with higher comorbidity burden. Atrial fibrillation (AF) was the most frequently occurring arrhythmia however atrial flutter (AFL) witnessed the highest rise during the study period. In general, there was a down trend in mortality with the greatest reduction occurring in patients with ventricular fibrillation/flutter (VF/VFL). The mean length of stay was higher if patients had arrhythmia, which led to increased cost of care from $16105 in 2003 to $19310 in 2014 (relative increase 22.9%, P < 0.001).

Conclusion

There is overall decline in HCM related hospitalizations but rise in hospitalization among HCM patients with arrhythmias. HCM with arrhythmia accounts for significant inpatient mortality coupled with prolonged hospital stay and increased cost of care. However, there is an encouraging downtrend in the mortality most likely because of improved clinical practice, cardiac screening and primary and secondary prevention strategies.
Serum Biomarkers Related to Glucocorticoid‐Induced Osteonecrosis of the Femoral Head: A Prospective Nested Case‐Control Study
Authors: Wang Xin‐Yuan , Hua Bing‐Xuan , Jiang Chang , Yuan Heng‐Feng , Zhu Liang , Fan Wen‐Shuai , Ji Zong‐Fei , Wang Zhe , Yan Zuo‐Qin
Published: June 2019

Early diagnosis and prevention of glucocorticoid (GC)‐induced osteonecrosis of the femoral head (ONFH) continues to be a challenging problem for clinicians and researchers. However, the role of circulating biomarkers for GC‐induced ONFH, which may reveal individual susceptibility and facilitate earlier diagnosis, remains to be determined. The aim of this study was to identify potential biomarkers that may predict early GC‐induced ONFH. A total of 123 patients scheduled for initial systemic GC therapy were enrolled in this prospective nested case–control study. The serum concentrations of 13 potential biomarkers were measured in seven patients with GC‐induced ONFH, diagnosed instantly after short‐term use of GCs and in 20 controls who did not develop osteonecrosis despite similar GC therapy. Biomarkers were measured both before and after taking GCs to identify any differences in marker levels and the changes during GC therapy between two groups. Type I collagen cross‐linked C‐telopeptide (β‐CTX; p = 0.000) was significantly lower, high‐density lipoprotein cholesterol (p = 0.092) and apolipoprotein (apo)‐B/apo‐A1 (p = 0.085) tended to be lower and higher, respectively, before GC treatment in osteonecrosis group. After GC therapy, β‐CTX (p = 0.014) was significantly lower and amino terminal telopeptide of procollagen type I (PINP; p = 0.068) tended to be lower in the osteonecrosis group. As secondary outcomes, we observed remarkable changes in nine potential biomarkers following short‐term GC therapy in both groups. In conclusion, we found that β‐CTX, could potentially be used to predict GC‐induced ONFH before GC therapy. Lower β‐CTX and PINP are promising biomarkers for the early diagnosis of GC‐induced ONFH. These findings need to be confirmed in large‐scale prospective studies. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:2348–2357, 2019
Effects of Substrate Stiffness on Morphology and MMP‐1 Gene Expression in Tenocytes Stimulated With Interleukin‐1β
Authors: Maeda Eijiro , Kuroyanagi Kaname , Ando Yoriko , Matsumoto Takeo
Published: June 2019

Tendon cells, tenocytes, are constantly subjected to mechanical stress in vivo, which maintains a level of cellular tension. When a tendon is subjected to overloading, local rupture of collagen fibers are induced, which deprives tenocytes of mechanical stress, lowers their cellular tension level and upregulates their catabolism. In addition, leukocytes are attracted to the rupture sites and produce interleukin‐1β (IL‐1β), and this exogenous IL‐1β also stimulates tenocyte catabolism. We tested a hypothesis that catabolic tenocytes with low cellular tension at the rupture sites excessively respond to the exogenous IL‐1β and further upregulate matrix metalloproteinase 1 (MMP‐1) gene expression. Tenocytes from rabbit Achilles tendon were cultured on the following substrates: glass or polydimethylsiloxane micropillar substrates with a height of 2, 4, or 8 µm. Following a 3‐day IL‐1β stimulation at a concentration of 0, 1, 10, or 100 pM, the effects of IL‐1β stimulation on cell morphology and MMP‐1 gene expression was analysed with fluorescent microscopy and fluorescence in situ hybridization, respectively. In addition, the effects of IL‐1β stimulation on cell membrane fluidity were examined. It was demonstrated that the cells on 8‐µm‐height micropillars exhibited a greater response than those on rigid substrates with flat (glass) and topologically the same surface (2‐µm‐height micropillars) to IL‐1β when supplied at the same concentration. Besides this, membrane fluidity was lower in the cells on micropillars. Therefore, it appears that cellular attachment to softer substrates lowers the cellular actin cortex tension, reducing the membrane fluidity and possibly elevating the sensitivity of IL‐1 receptors to ligand binding. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:150–159, 2020
Salinity and pH as factors affecting the passive sampling and extraction of pharmaceuticals from water
Authors: Lis Hanna , Stepnowski Piotr , Caban Magda
Published: July 2019

Passive sampling is an attractive technique for the long‐term monitoring of pharmaceuticals in the water environment. The reliability of the received results depends on the properly performed calibration, namely the determination of analyte sampling rates. This step can be the source of a systematic error, as the sampling rate values are dependent on the water donor phase parameters. This is especially important for pharmaceuticals, since their chemical characteristics and ionic form change with pH. In this study, the cross‐effect of pH (3, 7, and 9) and salinity (0, 7, and 35 practical salinity unit, using artificial sea water) on the passive sampling of 21 pharmaceuticals (antiparasitics, beta‐blockers, non‐steroidal anti‐inflammatory drugs, sulfonamides) was tested. The primarily determined parameter was the sampling rate. In addition, the extraction efficiency, partitioning coefficient, and the concentration of the analytes on the sorbent were calculated. Generally, for the non‐steroidal anti‐inflammatory drugs, beta‐blockers, and antiparasitics, the change both in pH and salinity had a negligible impact on the mentioned experimental parameters. In contrast, the extraction of sulfonamides was impacted by both pH and salinity, while lipophilicity was not a decisive parameter.
Imaging Features and Treatment Options for Breast Pseudoaneurysms After Biopsy: A Case‐Based Pictorial Review
Authors: Adler Kalie , Samreen Naziya , Glazebrook Katrina N. , Bhatt Asha A.
Published: June 2019

Pseudoaneurysm (PSA) formation is a potential complication of breast biopsies. Ultrasound is the most common imaging modality used for evaluation and treatment of a PSA. Color Doppler images show a cystic structure with swirling flow inside in a “to‐and‐fro” pattern. Treatment options for PSA include observation, ultrasound‐guided focused compression, thrombin injection, open surgical repair, and percutaneous embolization. The risks and benefits of these treatment options will be discussed in the following cases.
Changes in Carotid Duplex Ultrasound Velocities After Aortic Valve Replacement for Severe Aortic Stenosis
Authors: Shivapour Daniel M. , Javed Omair , Wu Yuping , Brinza Ellen , Hornacek Deborah , Conic Juliana , Gornik Heather L. , Kim Esther S. H.
Published: July 2019

Objectives

The peak systolic velocity (PSV) and end‐diastolic velocity (EDV) obtained by carotid duplex ultrasound (CDU) imaging of the internal carotid arteries (ICAs) are parameters used to determine the severity of ICA stenosis. Severe aortic stenosis (AS) results in a parvus‐et‐tardus pattern on spectral Doppler waveforms; however, the impact of severe AS on CDU velocities is unclear. The purpose of this study was to assess the impact of severe AS on CDU velocities by evaluating changes in CDU velocities before and after aortic valve replacement (AVR)

Methods

A single‐center retrospective review of patients with severe AS who underwent surgical AVR and who had preoperative and postoperative CDU examinations performed within 12 months of each other was conducted. Patients with any carotid intervention between the preoperative and postoperative CDU were excluded.

Results

We identified 92 patients who satisfied all inclusion criteria. The mean age was 72.2 years; 71.7% were men; the mean preoperative aortic valve area ± SD was 0.8 ± 0.2 cm2; and the mean time from preoperative to postoperative AVR CDU was 182.3 ± 98.4 days. The peak aortic valve gradient decreased from 62.5 to 22.0 mm Hg after AVR (P < .001); however, there were no significant changes in the PSV or EDV in either the right or left ICA.

Conclusions

Although severe AS may cause characteristic changes in the spectral Doppler waveform on CDU imaging, there is no significant effect on the ICA PSV or EDV. Adjustments in velocity criteria to determine the degree of carotid artery stenosis in patients with substantial AS may not be necessary.
The prognostic factors between different viral etiologies among advanced hepatocellular carcinoma patients receiving sorafenib treatment
Authors: Yeh Ming‐Lun , Huang Chung‐Feng , Huang Ching‐I , Hsieh Ming‐Yen , Hou Nei‐Jen , Lin I‐Hung , Liang Po‐Cheng , Tsai Yi‐Shan , Hsieh Meng‐Hsuan , Lin Zu‐Yau , Chen Shinn‐Chern , Dai Chia‐Yen , Huang Jee‐Fu , Yu Ming‐Lung , Chuang Wan‐Long
Published: June 2019

Sorafenib is currently the first‐line therapy for advanced hepatocellular carcinoma (aHCC) patients. However, the outcomes and prognostic factors of sorafenib therapy have not been well investigated. We aimed to investigate the pretreatment factors and outcomes among Taiwanese aHCC patients receiving sorafenib treatment. A total of 347 patients with aHCC and well‐compensated liver cirrhosis (Child‐Pugh A) status receiving sorafenib were consecutively enrolled from March 2013 through December 2016. Pre‐treatment clinical data and viral hepatitis markers were collected and analyzed with their outcomes. The primary endpoint of the study was overall survival. The factors associated with overall survival were also investigated. The median overall survival of all the patients was 238 days (range, 9‐1504 days) with a 1‐year overall survival of 43.2%. Positive hepatitis B surface antigen and absence of portal vein thrombosis (PVT) were independent factors associated with better overall survival. The median duration of sorafenib therapy was 93.0 days (range, 4‐1504 days). After stopping sorafenib, the median survival was 93.0 days (range, 1‐1254 days). The 1‐year survival after stopping sorafenib was 21.2%. In chronic hepatitis B patients, total bilirubin level was the only factor associated with overall survival. Hepatitis C antibody RNA negativity, tumor size, PVT, and white blood cell count were the independent factors associated with survival among those chronic hepatitis C patients. There were different prognostic factors stratified by viral etiologies in aHCC patients receiving sorafenib. Viral eradication increased survival in chronic hepatitis C patients.
Flood‐induced metal contamination in the topsoil of floodplain agricultural soils: A case‐study in Colombia
Authors: Marrugo‐Negrete José , Pinedo‐Hernández José , Combatt Enrique M. , Bravo Andrea G. , Díez Sergi
Published: June 2019

Anomalously cold conditions in the tropical Pacific, related to a strong La Niña event, affected numerous countries in 2010. Several areas in Colombia were severely impacted, including agricultural fields in La Mojana floodplain that were completely flooded for almost 2 years. This study assesses the effects of flooding on the levels, spatial distribution, and sources of trace metals in 222 agricultural topsoils of this floodplain. Our results show that mean concentrations of Cu 48.4 mg kg−1 (11–103 mg kg−1), Zn 79.2 mg kg−1 (6–207 mg kg−1), Ni 58.1 mg kg−1 (17–101 mg kg−1), Pb 3.2 mg kg−1 (0.13–14 mg kg−1), Cd 0.56 mg kg−1 (0.05–1.4 mg kg−1), Mn 411 mg kg−1 (55–1,277 mg kg−1), and Hg 0.10 mg kg−1 (0.05–0.22 mg kg−1) were higher than the world's averages. Topsoils revealed different degrees of pollution depending on the metal, of which Pb was the most problematic element, with 82% of the soil samples classified as heavily contaminated. Principal component analysis suggests that soil contamination was primarily derived from poor agricultural practices and contaminated river overflows from upstream mining areas. Our results show that an extreme flood event might increase the bioavailability of metals (especially Pb) for crops in most (66%) of the agricultural soils, posing a potential threat to human health.
A New Method for Percutaneous Drug Delivery by Thermo‐Mechanical Fractional Injury
Authors: Shavit Ronen , Dierickx Christine
Published: June 2019

Background and Objectives

Percutaneous drug delivery (PDD) is a means of increasing the uptake of topically applied agents into the skin. Successful delivery of a photosensitizer into the skin is an important factor for effective photodynamic therapy. To evaluate the efficacy of pretreatment by thermomechanical fractional injury (TMFI) (Tixel®, Novoxel®, Israel) at low‐energy settings in increasing the permeability of the skin to a known hydrophilic‐photosensitizer medication, 5‐amino‐levulinic‐acid hydrochloride (ALA) in compounded 20% ALA gel. To compare the effect of TMFI on ALA permeation into the skin in compounded gel to three commercial photosensitizing medications in different vehicles: ALA microemulsion gel, methyl‐amino‐levulinic‐acid hydrochloride (MAL) cream, and ALA hydroalcoholic solution.

Study Design/Materials and Methods

Five healthy subjects were treated in two separate experiments and on a total of 136 test sites, with four topical photosensitizer preparations as follows: compounded 20% ALA gel prepared in a good manufacturing practice (GMP)‐certified pharmacy (Super‐Pharm Professional, Israel), 10% ALA microemulsion gel (Ameluz®, Biofrontera Bioscience GmbH, Leverkusen, Germany), 16.8% MAL cream (Metvix®, Galderma, Lausanne, Switzerland), and 20% ALA hydroalcoholic solution (Levulan Kerastick®, DUSA Pharmaceuticals, Inc., Wilmington, MA, USA). The dermal sites were pretreated by Tixel® (Novoxel® Ltd., Israel) prior to topical drug application. One site was untreated to serve as control. Protoporphyrin IX (PpIX) fluorescence intensity readouts were taken immediately and 1, 2, 3, 4, and 5 hours posttreatment.

Results

The highest average PpIX fluorescence intensity measurements were obtained for the compounded 20% ALA gel following pre‐treatment by TMFI at 6 milliseconds pulse duration. After 2 and 3 hours, TMFI‐treated sites exhibited an increased hourly rate in readouts of FluoDerm units, which were 156–176% higher than the control rates (P ≤ 0.004). TMFI pre‐treatment did not enhance the percutaneous permeation of either ALA or MAL following the microemulsion gel, hydroalcoholic solution, and cream applications.

Conclusions

Pretreatment with low‐energy TMFI at a pulse duration of 6 milliseconds increased the percutaneous permeation of ALA linearly over the first 5 hours from application when the compounded 20% ALA gel was used. Formulation characteristics have substantial influence on the ability of TMFI pretreatment to significantly increase the percutaneous permeation of ALA and MAL. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.
Genetics and genetic counseling in psychiatry: Results from an opinion survey of professionals and users
Authors: Martorell Lourdes , Sanfeliu Annabel , Blázquez Ana , Lojo Elia , Cortés Maria José , de Pablo Joan , Vilella Elisabet
Published: June 2019

Background

The heritability of several psychiatric disorders is high, and specific at‐risk variants have been identified. Therefore, genetic counseling and genetic testing can be prescribed to some psychiatric patients, but these services are not standardized for most of the population. The aims of the study were to gather opinions from mental health professionals and users regarding (a) the genetics of psychiatric disorders and (b) the usefulness of a genetic counseling unit in psychiatry.

Methods

The survey was conducted in the province of Tarragona (Spain), and we analyzed 152 valid questionnaires from professionals and 959 from users.

Results

Sixty‐one percent of professionals strongly believed that psychiatric disorders have a genetic basis, and 59% rated a genetic counseling unit in psychiatry as very or extremely useful. However, only a few professionals reported that patients asked them about the genetics of their diseases (12%) or the possibility of transmitting the disease to offspring (19%). Forty‐seven percent of users strongly believed that psychiatric disorders have a genetic basis, 30% responded that they talked with their families about the genetics of their diseases, and 43% were worried about transmitting the disease to offspring; however, only 14% reported that their psychiatrist had talked to them about this topic. Remarkably, 80% of users would consider a genetic counseling unit very or extremely useful.

Conclusions

The present study showed that mental health professionals were more aware of the genetic basis of psychiatric disorders than users, and both considered the implementation of a genetic counseling service very useful.
Quantitative 1H NMR spectroscopy (qNMR) in the early process development of a new quorum sensing inhibitor
Authors: Cavalcante Robson A.F. , Silva Felipe L. , Favero Fernanda , Resck Inês S. , Pereira Alex L. , Machado Angelo H.L.
Published: June 2019

2‐methyl‐5,6,7,8‐tetrahydro‐2H‐chromen‐4(3H)‐one (called 6‐oxo) is presented as a new AI‐1 quorum sensing inhibitor for Vibrio harveyi. The development of a chemical process to afford traceable materials for new biological assays demands the development of analytical methods to ensure their purity and quality. This work describes the use of quantitative 1H nuclear magnetic resonance (NMR) spectroscopy (qNMR) to assess the purity of a sample of 6‐oxo (99.88%) and a sample of its major process impurity (E)‐1‐(2‐hydroxycyclohex‐2‐en‐1‐yl)but‐2‐en‐1‐one (called HCB; 98.28%). To explore the scope of the use of qNMR to quantify the amount of low‐content components in samples related to the chemical process for 6‐oxo synthesis, this work also determined the amount of 6‐oxo in two HCB samples: (a) the high‐purity HCB sample described above and (b) a crude HCB sample collected during the chemical process. Despite the complexity of the crude sample, the amount of 6‐oxo was readily assessed and could help to estimate the extent to which 6‐oxo was already formed during the HCB synthesis. This information can help the understanding of how the process parameters can be modified to improve the performance of the whole process, by controlling the reaction mechanisms working at each step of this chemical process. In this context, our results reinforce qNMR as a complementary analytical tool for the quantification of the main component found in a sample, contributing to the standardization of reference materials and thus allowing the development of analytical methods for process control and traceability of the samples used for biological assays.
Thermo‐/moisture‐responsive shape‐memory effect of poly(2‐ethyl‐2‐oxazoline) networks
Authors: Segiet Dominik , Raidt Thomas , Özdem Hatay , Weckes Sebastian , Tiller Joerg C. , Katzenberg Frank
Published: June 2019

In this work, poly(2‐ethyl‐2‐oxazoline) (PEtOx) is crosslinked to realize a moisture‐ and thermo‐responsive shape‐memory polymer. The obtained PEtOx networks exhibit excellent shape‐memory properties with storable strains of up to 650% and recovery values of 100% over at least 10 shape‐memory cycles. The trigger temperature (Ttrig) of 68 °C of a PEtOx network at a relative humidity (RH) of 0% decreases with increasing moisture and equals room temperature at an RH of 40%. Thus, programmed PEtOx networks trigger sensitively on a certain temperature/moisture combination and, further, can be programmed as well as triggered at room temperature exclusively by varying humidity. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019, 57, 1053–1061
Multimapping confounds ribosome profiling analysis: A case‐study of the Hsp90 molecular chaperone
Authors: Halpin Jackson C. , Jangi Radhika , Street Timothy O.
Published: June 2019

Ribosome profiling (Ribo‐seq) can potentially provide detailed information about ribosome position on transcripts and estimates of protein translation levels in vivo. Hsp90 chaperones, which play a critical role in stress tolerance, have characteristic patterns of differential expression under nonstressed and heat shock conditions. By analyzing published Ribo‐seq data for the Hsp90 chaperones in S. cerevisiae, we find wide‐ranging artifacts originating from “multimapping” reads (reads that cannot be uniquely assigned to one position), which constitute ~25% of typical S. cerevisiae Ribo‐seq datasets and ~80% of the reads from HEK293 cells. Estimates of Hsp90 protein production as determined by Ribo‐seq are reproducible but not robust, with inferred expression levels that can change 10‐fold depending on how multimapping reads are processed. The differential expression of Hsp90 chaperones under nonstressed and heat shock conditions creates artificial peaks and valleys in their ribosome profiles that give a false impression of regulated translational pausing. Indeed, we find that multimapping can even create an appearance of reproducibility to the shape of the Hsp90 ribosome profiles from biological replicates. Adding further complexity, this artificial reproducibility is dependent on the computational method used to construct the ribosome profile. Given the ubiquity of multimapping reads in Ribo‐seq experiments and the complexity of artifacts associated with multimapping, we developed a publicly available computational tool to identify transcripts most at risk for multimapping artifacts. In doing so, we identify biological pathways that are enriched in multimapping transcripts, meaning that particular biological pathways will be highly susceptible to multimapping artifacts.
Confirming the safety instrumented system layer of protection
Authors: Chastain‐Knight Denise
Published: June 2019

The safety instrumented system (SIS) is a complex protection layer with high reliability requirements. Assuring the effectiveness of the SIS requires monitoring the effectiveness of the safety instrumented functions (SIFs) as well as the independent protection layer(s) (IPL) that reduce demand on the SIF(s). An SIF tripping more frequently than anticipated may be due to flaws in IPLs intended to reduce demand on the SIF. A slower than expected or failed SIF trip may be due to flaws in the SIF components, the proof testing program, the maintenance program, or inadequate SIF design. This article will identify parameters that should be routinely monitored, illustrate how data can be captured and analyzed, detect weaknesses in the SIS IPL, and provide recommendations for routine monitoring and audit activities.
Computing weighted Szeged and PI indices from quotient graphs
Authors: Tratnik Niko
Published: June 2019

The weighted (edge‐)Szeged index and the weighted (vertex‐)PI index are modifications of the (edge‐)Szeged index and the (vertex‐)PI index, respectively, because they take into account also the vertex degrees. As the main result of this article, we prove that if G is a connected graph, then all these indices can be computed in terms of the corresponding indices of weighted quotient graphs with respect to a partition of the edge set that is coarser than the Θ*‐partition. If G is a benzenoid system or a phenylene, then it is possible to choose a partition of the edge set in such a way that the quotient graphs are trees. As a consequence, it is shown that for a benzenoid system, the mentioned indices can be computed in sublinear time with respect to the number of vertices. Moreover, closed formulas for linear phenylenes are also deduced.
A new approach to predict the formation of 3D hybrid organic‐inorganic perovskites
Authors: Kumar Aditya , Singh Ajeet , Ojha Animesh K.
Published: June 2019

Recently, hybrid organic‐inorganic perovskite (HOIPs) materials are used to enhance the power conversion efficiency of the solar cells. The tolerance factor (TF) and octahedral factor (μ) are widely used to predict the formation of three‐dimensional (3D) HOIPs structures. However, in some of the cases (e.g. CH3NH3GeI3 (MAGeI3) [TF = 1.06, μ = 0.33] NH2CHNH2GeI3 (FAGeI3) [TF = 1.14, μ = 0.33] and CH3C(NH2)2GeI3 (ACGeI3) [TF = 1.17, μ = 0.33]), these factors could not predict the formation of HOIPs structures. Thus, we have introduced a new factor based on the HOMO‐LUMO energy gap of the organic cations, metal cations, anions, and volume of the organic cations. We have tested and utilized the HOMO‐LUMO energy gap factor (β) on 403 ABX3 combinations. The factor β successfully predicts and differentiate the perovskite and non‐perovskite materials. Further, we also observed that for the formation of HOIPs structure, volume of the organic cation should also be in the range of 20 to 46 cm3/mol. Based on the newly reported factor, we have also designed some new organic cations which may form a 3D HOIPs structure.
Effect of project‐based learning on high school students' state‐mandated, standardized math and science exam performance
Authors: Craig Tara T. , Marshall Jill
Published: June 2019

In a technologically driven society, math and science students in the United States are falling further and further behind their international counterparts, resulting in an influx of STEM focused, reformed K‐12 schools, including schools focused on project‐based learning (PBL). This article reports a study of the effectiveness of PBL on high school students' performance on state mandated standardized mathematics and science achievement measures. Manor New Tech High School is a nationally recognized model STEM school, with a diverse student population, where all instruction is delivered through PBL. Although there is ample research suggesting that PBL is advantageous for increasing STEM learning compared to conventional teaching approaches, there is a lack of studies randomly assigning students to receive PBL. Further, some of the effects observed for students attending project‐based schools could be due to a self‐selection bias for students or parents that choose such an alternative learning environment. This study addresses both of these concerns and found that students taught through PBL, as a group, matched performance of conventionally taught students on all science 11th grade and mathematics 9th, 10th, and 11th grade TAKS achievement measures and exceeded performance by a scale score increase of 133 for the 10th grade science TAKS measure by (B = 133.082, t = 3.102, p < .05). One possible explanation of the differences observed in this study could be the TAKS instrument used to capture student math and science achievement that interprets “real‐life applications” of content differently between math and science questions. These results align with literature on the effects of PBL and deepen our understanding of these effects by providing a controlled study with random assignments to the PBL experience. Future research looking at the effect of PBL on achievement on the PISA could be beneficial in identifying benefits of PBL implementation in schools.
Effects of litter and additional enrichment elements on the occurrence of feather pecking in pullets and laying hens – A focused review
Authors: Schreiter Ruben , Damme Klaus , von Borell Eberhard , Vogt Isabelle , Klunker Michael , Freick Markus
Published: July 2019

Severe feather pecking (SFP) is a serious problem in the egg production industry with regard to animal welfare and performance. The multifactorial causes of SFP are discussed in the areas of genetics, feeding, husbandry, stable climate and management. Several studies on the influence of manipulable material on the incidence of SFP in different environments and housing systems have been performed. This review presents current knowledge on the effects of litter and additional enrichment elements on the occurrence of SFP in pullets and laying hens. Because SFP is associated with foraging and feed intake behaviour, the provision of manipulable material in the husbandry environment is an approach that is intended to reduce the occurrence of SFP by adequate exercise of these behaviours. As shown in the literature, the positive effect of enrichment and litter substrate on SFP in a low‐complexity cage environment is evident. On the other hand, consistent results have not been reported on the influence of additional enrichment material in housing systems with litter substrate, which represent the most common type of husbandry in Northwestern Europe. Thus, further research is recommended.
Fire Behavior of Natural Rubber Filled with Intumescent Flame Retardant Containing Graphite
Authors: Abdelkhalik Aksam , Makhlouf Ghada , Abdel‐Hakim Ahmed
Published: June 2019

Melamine salt of pentaerythritol phosphate/graphite (MPP‐G) mixture was prepared by dispersing graphite flakes in MPP during its synthesis. The chemical structure of MPP‐G was characterized by proton nuclear magnetic resonance, fourier‐transform infrared spectroscopy (FTIR), X‐ray diffraction (XRD), and scanning electron microscope. MPP‐G was blended with natural rubber (NR) at different loading levels and its effect on the thermal stability and flammability properties of NR was studied. The cone calorimeter results exhibited that the addition of MPP‐G to NR decreased the peak of heat release rate, mean heat release rate, total heat release, mean mass loss rate, mean effective heat of combustion, and maximum average rate of heat emission. Moreover, fire growth rate index and fire performance index values showed that NR/MPP‐G composites are safer than NR. The digital photographs of char formed after cone calorimeter test indicated the formation of a coherent char. The mechanism of flame retardation was studied based on FTIR, energy‐dispersive X‐ray spectrometry, and XRD analysis of char residue. J. VINYL ADDIT. TECHNOL., 26:155–164, 2020. © 2019 Society of Plastics Engineers
d‐Xylose consumption by nonrecombinant Saccharomyces cerevisiae: A review
Authors: Patiño Margareth Andrea , Ortiz Juan Pablo , Velásquez Mario , Stambuk Boris U.
Published: June 2019

Xylose is the second most abundant sugar in nature. Its efficient fermentation has been considered as a critical factor for a feasible conversion of renewable biomass resources into biofuels and other chemicals. The yeast Saccharomyces cerevisiae is of exceptional industrial importance due to its excellent capability to ferment sugars. However, although S. cerevisiae is able to ferment xylulose, it is considered unable to metabolize xylose, and thus, a lot of research has been directed to engineer this yeast with heterologous genes to allow xylose consumption and fermentation. The analysis of the natural genetic diversity of this yeast has also revealed some nonrecombinant S. cerevisiae strains that consume or even grow (modestly) on xylose. The genome of this yeast has all the genes required for xylose transport and metabolism through the xylose reductase, xylitol dehydrogenase, and xylulokinase pathway, but there seems to be problems in their kinetic properties and/or required expression. Self‐cloning industrial S. cerevisiae strains overexpressing some of the endogenous genes have shown interesting results, and new strategies and approaches designed to improve these S. cerevisiae strains for ethanol production from xylose will also be presented in this review.
Children’s Magical Realism for New Spatial Interactions: Augmented Reality and the David Almond Archives
Authors: Reynolds Kimberley , Schofield Tom , Trujillo-Pisanty Diego
Published: June 2019

This article draws on a multi-disciplinary project based on the David Almond archives at Seven Stories, the National Centre for Children’s Books in Newcastle upon Tyne, UK. The project combined archival research, augmented reality (AR) technology, Almond’s magical realist writing and experimental workshops to explore whether AR can enhance young people’s engagement with archives and literature. In the process it highlighted the extent to which Almond’s fiction is itself a form of augmentation that represents a particular geographical location—the North East of England—in ways that challenge official accounts of that place. This aspect of Almond’s writing corresponds to what Michel de Certeau describes as tactical spatial practice and is closely associated with some forms of AR.
Evolution of Fine‐Scale Segmentation at Intermediate‐Spreading Rate Ridges
Authors: Le Saout M. , Clague D.A. , Paduan J.B.
Published: July 2019

Mid‐ocean ridge axes are marked by segmentation of the axes and underlying magmatic systems. Fine‐scale segmentation has mainly been studied along fast‐spreading ridges. Here we offer insight into the third‐ and fourth‐order segmentation of intermediate‐spreading ridges and their temporal evolution. The Alarcón Rise and the Endeavour Segment have similar spreading rates (49 and 52.5 mm/year, respectively) but contrasting morphologies that vary from an axial high with a relatively narrow axial summit trough to an axial valley. One‐meter resolution bathymetry acquired by autonomous underwater vehicles, lava geochemistry, and ages from sediment cores is combined with available seismic reflection profiles to analyze variations in (1) geometry and orientation of the axial summit trough or valley, (2) seafloor depth near the axis, and (3) distribution of hydrothermal vents, (4) lava chemistry, and (5) flow ages between contiguous axes. Along both intermediate‐spreading segments, third‐ and fourth‐order discontinuities and associated segments are similar in dimension to what has been observed along fast‐spreading ridges. The Alarcón Rise and the Endeavour Segment also allow the study of the evolution of fine‐scale segmentation over periods of 300 to 4,000 years. Comparison between old and young axes reveals that the evolution of fine‐scale segmentation depends on the intensity of the magmatic activity. High magmatic periods are associated with rapid evolution of third‐order segments, while low magmatic activity periods, dominated by tectonic deformation and/or hydrothermal activity, are associated with little to no change in segmentation.
Characterization of Submesoscale Turbulence in the East/Japan Sea Using Geostationary Ocean Color Satellite Images
Authors: Choi J. , Park Y.‐G. , Kim W. , Kim Y. H.
Published: July 2019

Submesoscale processes are key in understanding physical and biological phenomena near the surface, but there remains a lack of observational evidence over large areas. We used hourly images from a geostationary satellite that can resolve variation in surface ocean color over an area of few hundred kilometers. The temporal variation in the surface chlorophyll a distribution captured by the satellite images was first used to generate a submesoscale‐permitting velocity field, from which we calculated the turbulence statistics such as kinetic energy spectra, velocity structure functions, and energy flux. Application to the April scenes in the East/Japan Sea showed that the kinetic energy spectra had a transition scale at 50 km that suggested two spectral regimes following k−3 and k−5/3, implying the coexistence of quasi‐geostrophic turbulence and surface quasi‐geostrophic turbulence. The chlorophyll a scalar spectrum suggested two spectral regimes of k−5/3 and k−1 with a transition at 3 km.
Laser-induced oxygen vacancies in FeCo2O4 nanoparticles for boosting oxygen evolution and reduction
Authors: Kang-Wen Qiu , Xi Cong , Zhang Yan , Zhang Rui , Li Zhe , Sheng Gu-Rong , Liu Hui , Dong Cun-Ku , Chen Yong-Jun , Du Xi-Wen
Published: June 2019

Abundant oxygen vacancies are successfully introduced into NiFe2O4 nanoparticles by laser fragmentation, resulting in dramatic improvement of catalytic activities for oxygen evolution and reduction.
Growth and theoretical study on the deep-ultraviolet transparent β-CsBa2(PO3)5 nonlinear optical crystal
Authors: Zhong Yang , Shan Pai , Sun Tongqing , Hu Zhenpeng , Liu Hongde , Liu Shiguo , Kong Yongfa , Xu Jingjun
Published: June 2019

A single crystal of β-CsBa2(PO3)5 has been successfully grown, and it exhibits a remarkable deep-UV cutoff edge of 168 nm.
Morphological evolution process of δ-MnO2 from 2-D to 1-D without phase transition
Authors: Fu Xin , Huo Wangchen , Liu Xiaoying , Shan Qianyuan , Guo Ziyang , Jing Chuan , Dong Fan , Yao Hong-Chang , Zhang Yuxin , Chen Ke
Published: June 2019

Morphological evolution of δ-MnO2 from nanosheets to nanofibers with direct pathways for electron transport.
Tunable pH-dependent oxygen evolution activity of strontium cobaltite thin films for electrochemical water splitting
Authors: Shi Yanuo , Xie Renjie , Liu Xuetao , Zhang Nian , Aruta Carmela , Yang Nan
Published: June 2019

Understanding the oxygen evolution reaction (OER) dependence on the reaction environment pH is important to find alternative strategies to define an optimal pH value for high electrocatalytic activity.
A palladium-catalyzed three-component cascade S-transfer reaction in ionic liquids
Authors: Li Jianxiao , Wu Yaodan , Hu Miao , Li Can , Li Meng , He Dandan , Jiang Huanfeng
Published: June 2019

A palladium-catalyzed three component cascade S-transfer reaction for the assembly of functionalized 4-sulfenylisoxazoles in ionic liquids was described.
Investigation of pre-service chemistry teachers’ understanding of radioactive decay: a laboratory modelling activity
Authors: Yeşiloğlu Sevinç Nihal
Published: June 2019

The first purpose of this study was to introduce a laboratory modelling activity focusing on teaching the concepts of radioactive elements/atoms, radioactive decay, and half-life. The second was to investigate pre-service chemistry teachers’ understanding of these concepts. Fifteen pre-service chemistry teachers who had enrolled in a Physical Chemistry Laboratory course participated in the study. The participants simulated the radioactive decay process of an imaginary radioactive element called Cornium during the laboratory modelling activity. In this way, pre-service chemistry teachers were able to visualize and model what is meant by radioactive decay and half-life. Data sources included responses given to open-response conceptual questions, participants’ drawings about radioactive decay and half-life, semi-structured interviews, activity worksheets, and observation notes. Qualitative analysis of data revealed that the pre-service chemistry teachers had misconceptions about the definition of radioactive elements/atoms, radioactive decay, and the half-life process before the activity. The role of the modelling activity in exposing and eliminating these misconceptions was discussed.