bluuebunny/crossref_metadata_2025 huggingface dataset:
Feasibility of sonographic access to the cricothyroid membrane in the presence of a rigid neck collar in healthy Chinese adults: A prospective cohort study
Authors: Wong Lok Yu , Yang Marc L. C. , Leung Hei Jim , Pak Chi Shing
Published: October 2019

Objectives

(1) To study the dimensions of cricothyroid membranes (CTMs) in healthy Chinese adults in two neck positions, one with rigid neck collar (RNC) and neck extended by ultrasonography (USG). (2) To evaluate how body habitus and neck positions may affect the access time of CTMs, and thus the feasibility for ultrasound‐guided cricothyroidotomy.

Methods

We scanned 39 adult staff of a local emergency department. Their CTMs were measured by two emergency physicians (EP) separately. The subjects' gender, weight, height, age, neck circumferences and BMI were collected. Image qualities (graded in ‘inadequate, adequate and good’) and image acquisition time of the CTMs were also recorded to ascertain proper CTM measurements.

Results

The mean depth of the CTM (neck extended) was 5.6 mm, and the standard deviation (SD) was 1.52. The mean depth (with RNC) was 5.97mm with SD 1.61. The mean length of the CTM (mm ± SD) with the neck extended and with the RNC was 10.5 ± 2.15 and 9.97 ± 2.24, respectively. The median image acquisition time for neck extended was 6.36s with interquartile range (IQR) of 2.32–8.4 s, while for RNC the median time was 5.60 s (IQR = 3.71–7.49; P = 0.539). Image acquisition time between the first and the second sonographers was similar. All subjects’ CTM could be identified readily by USG.

Conclusions

The CTM can be located quickly and reliably by bedside USG, even in overweight/obese persons with or without an RNC in place. We recommend that further study on the feasibility of bedside cricothyroidotomy with RNC kept on should be explored.
Chemoenzymatic Posttranslational Modification Reactions for the Synthesis of Ψ[CH2NH]‐Containing Peptides
Authors: Kato Yasuharu , Kuroda Tomohiro , Huang Yichao , Ohta Risa , Goto Yuki , Suga Hiroaki
Published: October 2019

The Ψ[CH2NH] reduced amide bond is a peptide isostere widely used in the development of bioactive pseudopeptides. Reported here is a method of chemoenzymatic posttranslational modification for the synthesis of Ψ[CH2NH]‐containing peptides converted from ribosomally expressed peptides. The posttranslational conversion composed of an enzymatic cyclodehydration and facile two‐step chemical reduction achieves deoxygenation of a specific amide bond present in a nonprotected peptide in water. This method generates the Ψ[CH2NH] bond in peptides and is applicable to various peptide sequences, potentially enabling the preparation of a library of Ψ[CH2NH]‐containing peptides.
High‐Entropy Layered Oxide Cathodes for Sodium‐Ion Batteries
Authors: Zhao Chenglong , Ding Feixiang , Lu Yaxiang , Chen Liquan , Hu Yong‐Sheng
Published: October 2019

Material innovation on high‐performance Na‐ion cathodes and the corresponding understanding of structural chemistry still remain a challenge. Herein, we report a new concept of high‐entropy strategy to design layered oxide cathodes for Na‐ion batteries. An example of layered O3‐type NaNi0.12Cu0.12Mg0.12Fe0.15Co0.15Mn0.1Ti0.1Sn0.1Sb0.04O2 has been demonstrated, which exhibits the longer cycling stability (ca. 83 % of capacity retention after 500 cycles) and the outstanding rate capability (ca. 80 % of capacity retention at the rate of 5.0 C). A highly reversible phase‐transition behavior between O3 and P3 structures occurs during the charge‐discharge process, and importantly, this behavior is delayed with more than 60 % of the total capacity being stored in O3‐type region. Possible mechanism can be attributed to the multiple transition‐metal components in this high‐entropy material which can accommodate the changes of local interactions during Na+ (de)intercalation. This strategy opens new insights into the development of advanced cathode materials.
Reaktionen des Bromylfluorids, BrO2F: Gemischtvalente Brom‐Sauerstoff‐Kationen, Br3O4+ und Br3O6+
Authors: Seppelt Konrad
Published: October 2019

Für das instabile und extrem reaktive BrO2F wird eine verlässliche Synthese beschrieben. Dieses wird in BrO2+ SbF6−, BrO2+ AsF6− und BrO2+ AsF6−⋅2 BrO2F umgewandelt. Letzteres zerfällt in Br3O4⋅Br2+ AsF6− mit fünf‐, drei‐ und einwertigem Brom. Mit HSO3CF3 bildet sich BrO2+H(SO3CF3)2−. Überschuss an BrO2F ergibt gemischtvalentes Br3O6+OSO3CF3− mit fünf‐ und dreiwertigem Brom. Reaktionen von BrO2F und MoF5 in SO2ClF oder CH2ClF ergeben Cl2BrO6+Mo3O3F13−. Die Reaktionen von BrO2F mit (CF3CO)2O und NO2 ergeben O2Br‐O‐CO‐CF3 und das bekannte NO2+Br(ONO2)2−. Alle diese Verbindungen sind thermodynamisch instabil.
Electrochemical evaluation of functionalized graphene oxide filled PVA‐chitosan biohybrid for supercapacitor applications
Authors: Shekhar Shashank , Sarkar Anjana , Sharma Bhasha , Jain Purnima
Published: October 2019

The evolution of eco‐friendly and cost efficient energy storage devices is eminent because of depletion of ozone layer and environmental issues. Biopolymer nanocomposites are the most auspicious aspirant to intercept hazardous situations. Chemical functionalization of graphene oxide (GO) is an essential component to avoid agglomeration of nanoparticles and it also helps in end‐use applications. Poly(vinyl alcohol) and chitosan biocomposite is prepared by magnetic stirring method followed by dispersion of nanofiller by ultrasonication process. The aim is to emphasize on usage of metal‐free material that is bionanocomposite, to exploit and enhance electrical properties of resultant product. The major drawback of chitosan is its low mechanical strength which can be overcome by employing GO and poly(vinyl alcohol). Scanning electron microscopy and transmission electron microscopy studies examined the uniform distribution of GO nanoparticles and functionalization improved the dispersion by creating nitrogen and hydroxyl moieties, this increases the intermolecular interactions between nanofiller and biopolymer matrix. The investigation of thermal analysis revealed the improved thermal stability and lower weight reduction on incorporation of GO and chemically functionalized GO. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48610.
A Diaminopropane Diolefin Ru(0) Complex Catalyzes Hydrogenation and Dehydrogenation Reactions
Authors: Casas Fernando , Trincado Monica , Rodriguez‐Lugo Rafael , Baneerje Dipshikha , Grützmacher Hansjörg
Published: October 2019

New ruthenium (0) complexes with a cooperative diolefin diaminopropane (DAP) or the dehydrogenated iminopropenamide ligand (IPA) were synthesized for comparison with their diaminoethane (DAE)/ diazadiene (DAD) ruthenium analogues. These DAP/IPA complexes are efficient catalysts in dehydrogenation reactions of alkaline aqueous methanol which proceeds under mild conditions (T=70 °C) and of higher alcohols, forming the corresponding carbonate and carboxylates, respectively. The scope of the reaction includes an example of a 1,2‐diol as model for biomass derived alcohols. Their catalytic applications are extended to the atom‐efficient dehydrogenative coupling of alcohols and amines to amides. The reaction proceeds without any additives and is applicable to the synthesis of formamides from methanol. Moreover, DAP/IPA complexes catalyze the hydrogenation of a series of esters, lactone, ketone, activated olefin, aldehyde and imine substrates. The diaminopropane Ru catalyst exhibits higher activity compared to the dehydrogenated β‐ketiminate (IPA) and previously studied DAD/DAE based catalysts. We present studies on their stoichiometric reactivity with relevance to their possible catalytic mechanisms and the isolation and full characterization of key reaction intermediates.
Physical Chemistry, a Discipline in Its Golden Age
Authors: Kuhn Alexander
Published: October 2019

Alexander Kuhn
is Full Professor at the Institute of Molecular Science (University Bordeaux, CNRS, Bordeaux INP) as well as Adjunct Professor at VISTEC (Thailand) and Henan University (China). He currently serves as a chair of the ChemPhysChem Editorial Board.
Optogenetic Modulation of a Catalytic Biofilm for the Biotransformation of Indole into Tryptophan
Authors: Hu Yidan , Liu Xiaobo , Ren Aloysius Teng Min , Gu Ji‐Dong , Cao Bin
Published: October 2019

In green chemical synthesis, biofilms as biocatalysts have shown great promise. Efficient biofilm‐mediated biocatalysis requires the modulation of biofilm formation. Optogenetic tools are ideal to control biofilms because light is noninvasive, easily controllable, and cost‐efficient. In this study, a gene circuit responsive to near‐infrared (NIR) light was used to modulate the cellular level of bis‐(3′‐5′) cyclic dimeric guanosine monophosphate (c‐di‐GMP), a central regulator of the prokaryote biofilm lifestyle, which allowed the regulation of biofilm formation by using NIR light. The engineered biofilm was applied to catalyze the biotransformation of indole into tryptophan in submerged biofilm reactors and NIR‐light‐enhanced biofilm formation resulted in an approximately 30 % increase in tryptophan yield, which demonstrates the feasibility of the application of light to modulate the formation and performance of catalytic biofilms for chemical production. The c‐di‐GMP‐targeted optogenetic approach to modulate catalytic biofilms showcases applications for biofilm‐mediated biocatalysis.
Decyanative Cross‐Coupling of Cyanopyrimidines with O‐, S‐, and N‐Nucleophiles: A Route to Alkoxylpyrimidines, Aminopyrimidines and Alkylthiopyrimidines
Authors: Wei Xiangyang , Zhang Caiyang , Wang Yifei , Zhan Qi , Qiu Guiying , Fan Ling , Yin Guodong
Published: October 2019

The transition metal‐free cross‐coupling reactions of cyanopyrimidines with aliphatic alcohols, thiols (or S‐alkylisothiourea salts) and amines, giving the corresponding alkoxylpyrimidines, aminopyrimidines, and alkylthiopyrimidines, are reported. Preliminary mechanistic studies reveal that it probably involves a sequential nucleophilic addition‐intramolecular rearrangement process, which is promoted by an intramolecular N–H···N five‐membered hydrogen bonding interaction. The presence of a nitrogen atom next to the cyano group is indispensable. The wide substrate scope with excellent yields makes cyanopyrimidines a promising alternative substrate class to the frequently used pyrimidines halides for the formation of C–O, C–S, and C–N bonds through the decyanative cross‐coupling reaction.
Closure of radial forearm free flap donor site: A comparative study between keystone flap and skin graft
Authors: Potet Pauline , De Bonnecaze Guillaune , Chabrillac Emilien , Dupret‐Bories Agnès , Vergez Sébastien , Chaput Benoit
Published: October 2019

Background

The aim was to investigate the feasibility of radial forearm free flap (RFFF) donor site closure by keystone flap (KF) and compare its outcomes to those of skin graft (SG) closure.

Methods

One hundred and one patients who underwent RFFF for head and neck reconstruction were included (35 KF closure and 65 SG closure). Duration of wound healing and donor site complications was collected. After a minimal follow‐up of 1 year, patients were questioned about functional and esthetic impairment.

Results

Coverage of donor site by KF was successful in all cases. The duration of wound healing was longer after SG than after KF (32 days vs 18 days, P < .001). Healing complications, esthetic and functional results were not statistically different.

Conclusion

Forearm donor site closure by KF is a feasible alternative to the traditional SG. Its main advantages are the reduced wound healing time and the avoidance of a second donor site.
Emotion regulation in posttraumatic stress disorder (PTSD): Rumination accounts for the association between emotion regulation difficulties and PTSD severity
Authors: Pugach Cameron P. , Campbell Allison A. , Wisco Blair E.
Published: October 2019

Objective

The current study investigated whether rumination accounts for the relationship between multiple aspects of emotion regulation (ER) difficulties and posttraumatic stress disorder (PTSD) severity.

Method

Participants were 90 community members (43% diagnosed with PTSD; Mage = 26.7, 86% female) who were interviewed using the Clinician‐Administered PTSD Scale‐5 and completed self‐reported measures of ER and rumination.

Results

The indirect effect of rumination completely accounted for the relationship between overall ER difficulties and PTSD severity. This finding was replicated for three unique aspects of ER (i.e., nonacceptance of negative emotions, impulse control difficulties under emotional distress, and the ability to maintain goal‐oriented behavior under emotional distress). Reverse models testing the indirect effect of ER on the link between rumination and PTSD were nonsignificant.

Conclusions

Rumination is an important cognitive process linking specific aspects of ER difficulties to PTSD. Clinical interventions focused on improving ER abilities among those with PTSD may benefit from targeting rumination.
microRNA‐132 inhibits cardiomyocyte apoptosis and myocardial remodeling in myocardial infarction by targeting IL‐1β
Authors: Zhao Zonglei , Du Song , Shen Shuxin , Wang Lixia
Published: October 2019

The patients suffering from myocardial infarction (MI) undergo cardiac remodeling with the features of expanded myocardial infarct size and dilated left ventricle. Multiple microRNAs (miRNAs) are emerged as crucial modulators to participate in the remodeling process. This study is mainly intended to clarify the regulatory mechanism of miR‐132 in the MI‐induced myocardial remodeling. miR‐132 low expression, while interleukin‐1β (IL‐1β) high expression was determined in MI by reverse‐transcription quantitative polymerase chain reaction and ELISA assays. MI rats showed decreased cardiac function and increased cardiomyocyte apoptosis. Moreover, miR‐132 and IL‐1β levels were altered in cardiomyocytes to explore their role in MI, with levels of proapoptotic or antiapoptotic proteins in MI together with cardiac function indexes observed. In addition, upregulation of miR‐132, decreased levels of Bax and Cleaved Caspase‐3, increased left ventricular ejection fraction, left ventricular fractional shortening, the maximum rate of rise or decrease of left ventricular pressure (±dp/dtmax), and Bcl‐2 level, which could be reversed by overexpressing IL‐1β. All in all, miR‐132 inhibits cardiomyocyte apoptosis so as to ameliorate myocardial remodeling in rats with MI through IL‐1β downregulation. Thus, miR‐132 is a potential candidate for the MI treatment.
AMPK‐mTOR‐ULK1 axis activation‐dependent autophagy promotes hydroxycamptothecin‐induced apoptosis in human bladder cancer cells
Authors: Wang Feifan , Cao Min , Fan Mengjing , Wu Hongshen , Huang Wei , Zhang Yan , Hu Zhenghui , Jin Xiaodong
Published: October 2019

10‐hydroxycamptothecin (HCPT), a natural plant extract, exerts anticancer capacity. HCPT has been reported to induce apoptosis and autophagy in human cancer cells. The interaction between autophagy and apoptosis induced by HCPT and the molecular mechanism in bladder cancer cells were investigated in this study. Our results confirmed that HCPT suppressed cell viability and migration and caused cell‐cycle arrest in T24 and 5637. Then, we used Z‐VAD(OMe)‐FMK to clarify that apoptosis induced by HCPT was mediated by caspase. Moreover, HCPT boosted autophagy through activating the AMPK/mTOR/ULK1 pathway. Blocking autophagy by 3‐methyladenine, the adenosine monophosphate‐activated protein kinase (AMPK) inhibitor dorsomorphin and siATG7 reversed HCPT‐induced cytotoxicity. Conversely, rapamycin and the AMPK activator AICAR enhanced growth inhibition and cell apoptosis, suggesting that autophagy played a proapoptosis role. Taken together, our findings showed that HCPT‐induced autophagy mediated by the AMPK pathway in T24 and 5637 cell lines, which reinforced the apoptosis, indicating that HCPT together with autophagy activator would be a novel strategy for clinical treatment in bladder cancer.
miR‐298 plays a pivotal role in colon cancer invasiveness by targeting PTEN
Authors: Arabsorkhi Zahra , Gharib Ehsan , Yaghmoorian Khojini Javad , Farhadieh Mohammad‐Erfan , Nazemalhosseini‐Mojarad Ehsan , Zali Mohammad Reza
Published: October 2019

Evidence indicate that the miR‐298 dysregulation might associate with colorectal cancer (CRC) development. Herein, we evaluated the effect of miR‐298 dysregulation on colon cancer invasiveness. First, metabolic activity, cell cycle progression, apoptosis, and invasion of miR‐298 overexpressed/knocked out colon cancer cells were examined and combined with their transcriptome analysis data for better visualization of miR‐298 intracellular signaling networks. Interaction between miR‐298 and its target was evaluated with luciferase assay and validated using western blot analysis. The proportion of abnormal miR‐298 level was investigated in tumor samples, matched normal adjacent tissues, and plasmas of 100 CRC patients, and also compared with 100 normal plasma samples. The Mann–Whitney U test was performed to assess miR‐298 differences among the studied groups, and the correlation between miR‐298 and the risk of CRC was shown by univariate and multivariate logistic regression. The data indicate that miR‐298 overexpression promoted proliferation and metastasis in CRC cells via targeting phosphatase and tensin homolog. Comparative analysis of CRC tumors, normal adjacent tissues, and plasmas indicated a significant miR‐298 upregulation in tumors and plasmas (1.72‐fold and 1.65‐fold, respectively; p < .001). Also, the aberrant level of miR‐298 contributed with CRC tumor differentiation, TNM stage and lymph node metastasis (p < .001), and independently associated with poor survival of CRC patients (p < .029; hazard ratio: 1.292; 95% confidence interval: 0.339–2.184). Collectively, these data showed that abnormal level of miR‐298 correlated with cancer development and through that lowered the overall survival rate of CRC patients. Therefore, miR‐298 could be considered as a therapeutic target for CRC.
One‐step synthesis of a WO3‐CuS nanosheet heterojunction with enhanced photocatalytic performance for methylene blue degradation and Cr(VI) reduction
Authors: Liu Yating , Li Ming , Zhang Qingyan , Qin Picai , Wang Xiandong , He Guannan , Li Ling
Published: October 2019

BACKGROUND

The photocatalytic activity of a pristine semiconductor is unsatisfactory due to the rapid recombination of photogenerated electrons and holes. Constructing composite photocatalysts has proven to be an effective method to suppress electron–hole recombination. The composites composed of two materials usually are synthesized through a two‐step process. However, in this work, a simple one‐step solvothermal method employing an homogeneous reaction system was adopted to synthesize a tungsten trioxide (WO3)‐copper sulfide (CuS) nanosheet heterojunction with enhanced photocatalytic properties.

RESULTS

The formation of the WO3‐CuS heterojunction was confirmed by X‐ray diffraction, transmission electron microscopy, energy‐dispersive X‐ray and X‐ray photoelectron spectroscopy analysis. The composites showed improved visible light harvesting ability, and enhanced photoelectric and photocatalytic properties compared with pure WO3. The optimized composite displayed a photocurrent almost five‐fold greater than the sum of the photocurrents of WO3 and CuS, and had superior performance for methylene blue (MB) degradation and hexavalent chromium [Cr(VI)] reduction. The MB degradation and Cr(VI) reduction efficiencies were both improved when they co‐existed in the photocatalytic system. Interferential ions Cl− and NO3− were much less effective in the degradation of MB than in the reduction of Cr(VI).

CONCLUSIONS

Improved photocatalytic activity was achieved after coupling CuS with WO3, due to the enhanced visible light absorption and efficient electron–hole separation. Photogenerated holes were found to be the dominant reactive species in the MB photodegradation process. A synergistic effect existed between MB degradation and Cr(VI) reduction. Interferential ions Cl− and NO3− had much greater effect on Cr(VI) reduction than MB degradation. © 2019 Society of Chemical Industry
Novel nomogram with microvascular density in the surgical margins can accurately predict the risk for anastomotic leakage after anterior resection for rectal cancer
Authors: Xiao Chanchan , Zhou Meihua , Yang Xihua , Xiao Fangtao , Liu Xiaofei , Guo Yi , Li Xiaojie , Cao Huiqiu , Luo Jihui
Published: October 2019

Abstracts

Background

Anastomotic leakage (AL) is a serious complication after anterior resection. The purpose of this study was to determine the role of microvascular density (MVD) in AL and to develop a nomogram to accurately predict AL.

Methods

This study retrospectively enrolled 477 consecutive patients who underwent anterior resection for rectal cancer from January 2011 to January 2019. Tissue samples of the resection margins were assessed for MVD. Univariate and multivariate regression analyses were used to identify the risk factors for AL.

Results

The incidence of clinical AL was 6.7%. MVD in the distal margin was associated with AL (P < .001). Univariate and multivariate regression analysis identified the following variables as independent risk factors for AL: preoperative albumin ≤35 g/L (odds ratio [OR] = 2.511), neoadjuvant treatment (OR = 3.560), location of tumor ≤7 cm (OR = 3.381), blood loss ≥100 mL (OR = 2.717), and MVD in the distal margin ≤20 (OR = 4.265). Then, a nomogram including these predictors was developed. The nomogram showed good discrimination (AUC = 0.816) and calibration (concordance index = 0.816). The decision curve analysis demonstrated that the nomogram was clinically useful.

Conclusions

MVD in the distal margin is closely associated with AL. The nomogram can be used for individualized prediction of AL after anterior resection for patients with rectal cancer.
Duodenal neuroendocrine tumors: Somewhere between the pancreas and small bowel?
Authors: Gamboa Adriana C. , Liu Yuan , Lee Rachel M. , Zaidi Mohammad Y. , Staley Charles A. , Kooby David A. , Winer Joshua H. , Shah Mihir M. , Russell Maria C. , Cardona Kenneth , Maithel Shishir K.
Published: October 2019

Background

While sub‐2 cm pancreatic neuroendocrine tumors (NETs) are often observed, small bowel‐NETs undergo resection and lymphadenectomy regardless of size. Aim was to define the natural history of duodenal (D‐NETs), determine the role of resection, and define the factors associated with overall survival (OS) after resection.

Methods

National Cancer Database (2004‐2014) was queried for the patients with nonmetastatic/nonfunctional D‐NETs. Local resection (LR): local excision/polypectomy/excisional biopsy. Anatomic resection (AR): radical surgery. Tumor size was divided into less than 1 cm, 1 to 2 cm, and ≥2 cm. Propensity score weighting was used to create balanced resection and no‐resection cohorts. The primary endpoint was OS.

Results

Among 5502 patient, the median age was 65 years. The median follow‐up was 49 months. The median tumor size was 0.8 cm. Resection was performed in 72% (n = 3954; LR: 61%, AR: 39%). Lymph node (LN) resection was performed in 26% (43% had metastasis). A total of 74% had negative margins. Resection and no‐resection cohorts were propensity score weighted for age/sex/race/Charlson‐Deyo score/tumor grade (all independently associated with OS on multivariable analysis). Resection was associated with improved median OS compared to no resection in all sizes (<1 cm: median not reached vs 194 months; 1‐2 cm: median not reached vs 56 months; >2 cm: median not reached vs 90 months; all P < .01). Subset analysis of each resection size cohort demonstrated that neither type of resection, LN retrieval, LN positivity, or margin status was associated with OS (all P > .05).

Conclusion

Patients with nonmetastatic and nonfunctional D‐NETS should be considered for resection regardless of tumor size. Given the lack of prognostic value, the resection type and extent of LN retrieval should be tailored to each patient's clinical picture and safety profile.
Microstrip antenna with high self‐interference cancellation using phase reconfigurable feeding network for in‐band full duplex communication
Authors: Chaudhary Girdhari , Jeong Junhyung , Jeong Yongchae , Ham Woonchul
Published: October 2019

This article presents a bistatic microstrip circular patch antenna with high self‐interference cancellation (SIC) through phase reconfigurable differential feeding network. The proposed microstrip antenna consists of closely spaced transmitter and receiver patches having orthogonal polarization with respect to each other. To achieve high SIC, the phase reconfigurable of feeding network can assist in tracking the phase offsets of self‐interference signal caused by fabrication error or scattering nearby objects. From the experiment, the proposed antenna provided higher than 75 dB (65 dB) SIC bandwidth for 36 MHz (50 MHz) at the center frequency of 2.50 GHz. The proposed antenna is a good candidate for in‐band full duplex communication system because of its simple design.
In vitro culture of secondary follicles and prematuration of cumulus–oocyte complexes from antral follicles increase the levels of maturation‐related transcripts in bovine oocytes
Authors: Bezerra Francisco Taiã G. , Lima Francisco Edilcarlos O. , Paulino Laís Rayani F. M. , Silva Bianca R. , Silva Anderson W. B. , Souza Ana Liza P. , van den Hurk Robert , Silva José Roberto V.
Published: October 2019

This study evaluates the levels of messenger RNA (mRNA) for eIF4E, PARN, H1FOO, cMOS, GDF9, and CCNB1 in oocytes from secondary and antral follicles at different stages of development. The effects of in vitro culture, in vitro prematuration, and in vitro maturation on the expression of these genes on oocytes were also analyzed. The results showed that mRNA levels for H1FOO, GDF9, and PARN were higher in oocytes from small, medium, and large antral follicles, respectively, than those seen in secondary follicles. Oocytes from small, medium, and large antral follicles had higher levels of CCNB1 than oocytes from secondary follicles. Oocytes from cultured secondary follicles had higher levels of GDF9, CMOS, PARN, eIF4E, CCNB1, and H1FOO than before culture. Prematured oocytes from small antral follicles had higher levels of mRNA for GDF9, PARN, and eIF4E than before culture. In addition, higher levels of cMOS and H1FOO were identified in prematured oocytes from medium antral follicles. In conclusion, follicular growth is associated with an increase in the expression of H1FOO, GDF9, CCNB1, and PARN. The culture of secondary follicles, prematuration, and maturation of oocytes from antral follicles increase the expression of eIF4E, PARN, H1FOO, cMOS, GDF9, and CCNB1.
Novel Conjugated Side Chain Fluorinated Polymers Based on Fluorene for Light‐Emitting and Ternary Flash Memory Devices
Authors: Zhang Qian , Ma Dongge , Wen Dianzhong , Wang Cheng , Bai Xuduo , Wang Shuhong
Published: October 2019

Three novel conjugated polymers based on 9,9′‐dioctylfluorene unit and isoindolo[2,1‐a]benzimidazol‐11‐one with different fluorine substituents (0, 2 and 4) were synthesized. PLED and resistive memory devices based on these polymers were prepared consequently. PLED based on four‐fluorinated polymer showed the highest maximum brightness of 3192 cd m−2 with almost 5‐fold increase of current efficiency 8‐fold increase of external quantum efficiency compared to that of the other two, and all the PLEDs exhibited good emission stability with no noticeable change of electroluminescence even under high voltage of 10 V. The memory device of doubly‐fluorinated polymer exhibited ternary flash behavior with threshold voltages below −2.5 V, while device of four‐fluorinated polymer possessed ON/OFF current ratio above 104. Impact of fluorine substitutions on the performance of devices were briefly investigated. The results revealed that the improvement of device performance might not scale with the increasing number of fluorine substitutions, and the four‐fluorine‐substituted polymer and doubly‐fluorinated polymer could be encouraging materials for applications of PLED and resistive memory device and worth of further design of other new polymer systems.
Influence of Calcination Conditions on Structural and Solid‐State Kinetic Properties of Iron Oxidic Species Supported on SBA‐15
Authors: Genz Nina Sharmen , Ressler Thorsten
Published: October 2019

Iron oxidic species supported on silica SBA‐15 were synthesized with various iron loadings using two different FeIII precursors. The effect of varying powder layer thickness during calcination on structural and solid‐state kinetic properties of FexOy/SBA‐15 samples was investigated. Calcination was conducted in thin (0.3 cm) or thick (1.3 cm) powder layer. Structural characterization of resulting FexOy/SBA‐15 samples was performed by nitrogen physisorption, X‐ray diffraction, and DR‐UV/Vis spectroscopy. Thick powder layer during calcination induced an increased species size independent of the precursor. However, a significantly more pronounced influence of calcination mode on species size was observed for the FeIII nitrate precursor compared to the FeIII citrate precursor. Temperature‐programmed reduction (TPR) experiments revealed distinct differences in reducibility and reduction mechanism dependent on calcination mode. Thick layer calcination of the samples obtained from FeIII nitrate precursor resulted in more pronounced changes in TPR profiles compared to samples obtained from FeIII citrate precursor. TPR traces were analyzed by model‐dependent Coats‐Redfern method and model‐independent Kissinger method. Differences in solid‐state kinetic properties of FexOy/SBA‐15 samples dependent on powder layer thickness during calcination correlated with differences in iron oxidic species size.
Characterization of a microwave plasma jet (TIAGO) in‐contact with water: Application in degradation of methylene blue dye
Authors: Hamdan Ahmad , Gagnon Clara , Aykul Melisa , Profili Jacopo
Published: October 2019

Plasma in or in‐contact with liquids is a research field that has great potential in the treatment of wastewater. Today, efforts are focused on finding a plasma source that can efficiently remove persistent pollutants from water. In this study, we evaluate the effectiveness of a microwave plasma jet, in TIAGO (Torche à Injection Axiale sur Guide d'Ondes) configuration, using methylene blue (MB) as a model organic contaminant. The assessments conducted herein show that MB degradation is promoted at short nozzle–water distance, high gas flow rate, elevated microwave power, and excessive initial water conductivity (up to 10,000 µS/cm). The plasma characteristics, namely composition, electron density, and OH rotational temperature, as well as water acidity and conductivity are also evaluated.
Peppy: A virtual reality environment for exploring the principles of polypeptide structure
Authors: Doak David G. , Denyer Gareth S. , Gerrard Juliet A. , Mackay Joel P. , Allison Jane R.
Published: October 2019

A key learning outcome for undergraduate biochemistry classes is a thorough understanding of the principles of protein structure. Traditional approaches to teaching this material, which include two‐dimensional (2D) images on paper, physical molecular modeling kits, and projections of 3D structures into 2D, are unable to fully capture the dynamic 3D nature of proteins. We have built a virtual reality application, Peppy, aimed at facilitating teaching of the principles of protein secondary structure. Rather than attempt to model molecules with the same fidelity to the underlying physical chemistry as existing, research‐oriented molecular modelling approaches, we took the more straightforward approach of harnessing the Unity video game physics engine. Indeed, the simplicity and limitations of our model are strengths in a teaching context, provoking questions and thus deeper understanding. Peppy allows exploration of the relative effects of hydrogen bonding (and electrostatic interactions more generally), backbone φ/ψ angles, basic chemical structure, and steric effects on a polypeptide structure in an accessible format that is novel, dynamic, and fun to use. Apart from describing the implementation and use of Peppy, we discuss the outcomes of deploying Peppy in undergraduate biochemistry courses.
Assessing the ratio of means as a causal estimand in clinical endpoint bioequivalence studies in the presence of intercurrent events
Authors: Lou Yiyue , Jones Michael P. , Sun Wanjie
Published: October 2019

In clinical endpoint bioequivalence studies, the observed per‐protocol (PP) population (compliers and completers in general) is usually used in the primary analysis for equivalence assessment. However, intercurrent events, ie, missingness and noncompliance, are not properly handled. The resulting estimand is not causal. Previously, we proposed the first causal framework to assess equivalence in the presence of missing data and noncompliance. We proposed a causal survivor average causal effect (SACE) estimand for the difference of means (DOM). In equivalence assessment, DOM is not as widely used as the ratio of means (ROM). However, no existing formula links the observed PP estimand to the SACE estimand for ROM as exists for DOM. Herein, we propose a similar causal framework for ROM using the principal stratification approach, one of the strategies recommended by the International Conference on Harmonisation (ICH) E9 R1 addendum. We quantify the bias of the observed ROM PP estimand for the SACE estimand, which provides a basis to identify three conditions under which the two estimands are equal. We propose a sensitivity analysis method to evaluate the robustness of the current PP estimator to estimate the SACE estimand. We extend Fieller's confidence interval for the SACE estimand using ROM, which can be applied to many settings. Simulation demonstrates that the PP estimator is biased in either directions and may inflate type 1 error and/or change power when the three identified conditions are violated. Our work can be applied to comparative clinical biosimilar studies.
Enhancing Photovoltaic Performance of Aromatic Ammonium‐based Two‐Dimensional Organic‐Inorganic Hybrid Perovskites via Tuning CH···π Interaction
Authors: Yan Liang , Hu Jun , Zhou Ninghao , Moran Andrew M. , You Wei
Published: October 2019

Phenethylammonium (PEA)‐based 2D perovskite is an interesting example of 2D perovskites, serving as the gateway for further introduction of functional conjugated organic cations into 2D perovskites for a variety of applications, for example, photovoltaics. However, the efficiency of photovoltaic devices based on PEA 2D perovskites only achieved ≈7% for  = 3, which was significantly lower than that achieved for other cation‐based 2D perovskites. Here, by introducing propyl ammonium (C3A) into the PEA‐based 2D perovskites, the device efficiency is improved to ≈10% for 1:1 C3A:PEA‐based 2D perovskites ( = 3). Further investigation reveals that tuning the CH···π interaction (between C3A and PEA or between two PEA molecules) can have multiple beneficial impacts on such modified 2D perovskites, including a) removal of undesirable n = 1 phase, b) lowering the density of trap states, and c) achieving larger crystalline grains. Additionally, after substitution with 50% C3A, other aromatic ammonium cation‐based 2D perovskites ( = 3) also show similar efficiency enhancement in their photovoltaic devices, thus exhibiting the general applicability of this method. The results of this study highlight that the strategic tuning of non‐covalent interactions (such as CH···π interaction) is a viable and important method to further develop 2D perovskites for photovoltaics.
Regioisomer‐Free Chlorinated Thiophene‐Based Ending Group for Thieno[3,2‐b]thiophene Central Unit‐Based Acceptor Enabling Highly Efficient Nonfullerene Polymer Solar Cells with High Voc Simultaneously
Authors: Ni Shan-Shan , Xu Xiaopeng , Wang Jin-Liang , Wan Shi-Sheng , Liu Kai-Kai , Bai Hai-Rui , Yang Can , Lv Guiqin , Peng Qiang
Published: October 2019

A pair of pure regioisomeric acceptor–donor–acceptor (A–D–A) typed nonfullerene small molecule acceptors (NF‐SMAs) (4TTIC and 4TTIC‐Cl), containing a central thieno[3,2‐b]thiophene‐sp3 hybridized “carbon‐bridge”‐based fused ring core unit and thiophene‐based IC or chlorinated thiophene‐based IC are synthesized for polymer solar cells (PSCs). Compared with 4TTIC, 4TTIC‐Cl not only achieves a red‐shifted absorption spectra and lower energy levels but also enhancement of molecular packing and crystallinity. The 4TTIC‐Cl‐based blend films display higher and more balanced charge carrier mobilities, more favorable morphology, and more efficient exciton dissociation in comparison with the 4TTIC‐based blend film. The optimized devices based on PBDB‐ST:4TTIC‐Cl deliver an impressively high power conversion efficiency (PCE) of 13.11% and fill factor of 74%, much higher than that of the PBDB‐ST:4TTIC‐based devices. Moreover, a small energy loss of ≈0.54 eV and a decent Voc of 0.88 V are simultaneously achieved for PBDB‐ST:4TTIC‐Cl‐based devices. Noticeably, the PCE of 13.11% is the highest reported value for NF‐SMAs containing the central thieno[3,2‐b]thiophene unit with sp3 hybridized carbon‐bridged cyclopentadiene fragments in binary PSCs. This study proves that introduction of less electron‐deficient thiophene‐based IC terminal group into thieno[3,2‐b]thiophene central core‐based SMAs is a very effective method for making high Voc and excellent PCE simultaneously.
Prediction of Inclusion State in Molten Steel by Morphology and Appearance of Inclusions in Liquid Steel Samples
Authors: Alatarvas Tuomas , Vuolio Tero , Heikkinen Eetu-Pekka , Shu Qifeng , Fabritius Timo
Published: October 2019

Inclusions are unwanted but to some extent inevitable in molten and solid steel. Usually solid inclusions are considered to be the most harmful. Inclusions can be converted into a less detrimental form with calcium treatment. The success of calcium treatment can be evaluated by analyzing the state of the inclusion population. The state of inclusions is usually determined by computational thermodynamics making use of the chemical composition of inclusions and system conditions. In this process, liquid and solid inclusions are usually distinguished. Herein, a classification procedure which combines computational thermodynamics and data‐driven reasoning is presented. The objective of this work is to study the predictability of the inclusion state based on its appearance and morphological properties. As a result, Al2O3–CaO–MgO–CaS inclusions are classified as liquid and solid ones based on their aspect ratio, equivalent circle diameter, and mean gray value with a recall of 82.7% and precision of 84.9%, by making use of a logistic regression‐based classifier.
Corrosion Mechanism of MgO–CMA–C Ladle Brick with High Service Life
Authors: Wöhrmeyer Christoph , Gao Simon , Ping Zhenfeng , Parr Christopher , Aneziris Christos G. , Gehre Patrick
Published: October 2019

Carbon‐bonded magnesia and magnesia alumina carbon (MAC) bricks have been used in the sidewalls and bottom of steel ladles for over 20 years. Due to the increasing ratio of scrap to steel, higher working temperature, and prolonged refining time, steel producers seek refractories with enhanced service lifetime. Therefore, a new generation of MgO–C bricks with addition of calcium magnesium aluminate (CMA) aggregates is tested in a ladle lining of an integrated steel shop for 138 cycles. The corrosion mechanisms are evaluated by digital light microscopy and with scanning electron microscopy (SEM) equipped with energy‐dispersive X‐ray spectroscopy (EDS). The industrial trial tests reveal the formation of a slag coating at the hot face, leading to a much slower corrosion rate compared with a common MgO–C lining. The dissolution of the CMA aggregates and MgO grains results in a significant change of the slag chemistry and viscosity causing a reduced infiltration and corrosion behavior of the ladle slag. Also, the ability of bonding iron plays a major role, leading to the formation of brownmillerite phase in the protective slag coating on top of the bricks.
Induced pluripotent stem cells reprogrammed from primary dendritic cells provide an abundant source of immunostimulatory dendritic cells for use in immunotherapy
Authors: Horton Christopher , Davies Timothy J. , Lahiri Priyoshi , Sachamitr Patty , Fairchild Paul J.
Published: October 2019

Cell types differentiated from induced pluripotent stem cells (iPSCs) are frequently arrested in their development program, more closely resembling a fetal rather than an adult phenotype, potentially limiting their utility for downstream clinical applications. The fetal phenotype of iPSC-derived dendritic cells (ipDCs) is evidenced by their low expression of MHC class II and costimulatory molecules, impaired secretion of IL-12, and poor responsiveness to conventional maturation stimuli, undermining their use for applications such as immune-oncology. Given that iPSCs display an epigenetic memory of the cell type from which they were originally derived, we investigated the feasibility of reprogramming adult DCs to pluripotency to determine the impact on the phenotype and function of ipDCs differentiated from them. Using murine bone marrow-derived DCs (bmDCs) as proof of principle, we show here that immature DCs are tractable candidates for reprogramming using non-integrating Sendai virus for the delivery of Oct4, Sox2, Klf4, and c-Myc transcription factors. Reprogramming efficiency of DCs was lower than mouse embryonic fibroblasts (MEFs) and highly dependent on their maturation status. Although control iPSCs derived from conventional MEFs yielded DCs that displayed a predictable fetal phenotype and impaired immunostimulatory capacity in vitro and in vivo, DCs differentiated from DC-derived iPSCs exhibited a surface phenotype, immunostimulatory capacity, and responsiveness to maturation stimuli indistinguishable from the source DCs, a phenotype that was retained for 15 passages of the parent iPSCs. Our results suggest that the epigenetic memory of iPSCs may be productively exploited for the generation of potently immunogenic DCs for immunotherapeutic applications.
Advances and challenges in modeling solvated reaction mechanisms for renewable fuels and chemicals
Authors: Basdogan Yasemin , Maldonado Alex M. , Keith John A.
Published: October 2019

We provide a critical overview of progress and challenges in computationally modeling multistep reaction mechanisms relevant for catalysis and electrocatalysis. We first discuss how the chemical and materials space of energetically efficient catalysis can be explored with computational chemistry. Since reactions for renewable energy catalysis can involve acid–base chemistry and/or ions under aqueous conditions, we then summarize how solvation can be modeled with quantum chemistry schemes using implicit, mixed implicit/explicit, and fully explicit solvation modeling. We will discuss the insights (and limitations) of these solvation models primarily through the scope of understanding CO2 reduction reaction mechanisms, but these will also be applicable for future work elucidating other reaction mechanisms of critical importance for human sustainability such as H2O oxidation and N2 reduction.

This article is categorized under:

Structure and Mechanism > Reaction Mechanisms and Catalysis
The addition of soil and chitin into Sunda pangolin (Manis javanica) diets affect digestibility, faecal scoring, mean retention time and body weight
Authors: Cabana Francis , Tay Claudia
Published: October 2019

Pangolins (Manis spp.) are myrmecophagous mammals with a wild diet of termites and ants. Diets are not yet readily acceptable by all pangolins and lack soil and chitin compared to their wild diet. This study aimed to assess the usefulness of including soil and chitin in pangolin diets by measuring changes in digestibility, food mean retention time, faecal scoring and body weight changes. Two male and two female Sunda pangolins (Manis javanica) from Night Safari (Singapore) were fed their typical gruel‐type diets, with soil and chitin added in various amounts throughout 10 different treatments. Diet intake was calculated daily and faecal boluses were collected for digestibility analysis. Chromium oxide was added to the diet to measure mean retention time four times per animal per treatment. Faecal consistency scores were recorded daily where 1 is firm and 5 is liquid. Every animal was weighed weekly. Adding soil or chitin to the diet had various effects on the apparent digestibility of organic matter, crude protein and fiber with little effects on crude fat or calcium. Soil had a general positive influence on organic matter and fiber digestion. The addition of chitin and soil together had the stronger effects. Only at 25% inclusion of soil did the faecal score begin to improve. The overall maintenance energy requirements for adult M. javanica was 79.28 Kcal/kg BW0.75/day, similar to other myrmecophagous mammals. The usage of soil and chitin in pangolin diets may be helpful in controlling weights while preventing behaviours associated with hunger.
Precise predictions for single-top production: the impact of EW corrections and QCD shower on the t-channel signature
Authors: Frederix Rikkert , Pagani Davide , Tsinikos Ioannis
Published: October 2019

Abstract

In this work we calculate and provide precise predictions for the signature that is typically exploited at the LHC for the measurement of t-channel single-top production: 1 lepton, 1 light jet, 1 b-jet, Ɇ

T
and no additional jets or leptons. We apply the cuts that define the fiducial region and we take into account all the contributions to this signature; not only those from resonant t-channel single-top production. On the one hand, we calculate the complete-NLO corrections, i.e., all NLO effects of QCD and EW origin. On the other hand, we study in detail the impact of a QCD parton shower for the fiducial region we consider. We provide predictions in different approximations at the inclusive level and for several differential distributions. Our study demonstrates the relevance of both EW corrections and shower effects for obtaining precise and reliable theoretical predictions for the single-top-production fiducial region.