bluuebunny/crossref_metadata_2025 huggingface dataset:
Revealing the Nanoscale Dynamics of the Extracellular Space in the Living Brain
Authors: Godin Antoine G , Dannée Noemie , Groc Laurent , Cognet Laurent
Published: May 2020

The brain is a highly dynamic structure with the extracellular space taking up almost a quarter of its volume. Signalling molecules, neurotransmitters and nutrients transit via the extracellular space, which constitutes a key microenvironment for cellular communication and clearance of toxic metabolites. Nevertheless, the extracellular space has not been characterized in detail in intact living samples because of the lack of appropriate tools allowing its study. Recent technological advances enhancing the luminescence properties and biocompatibility of carbon nanotubes opened the door to super-resolution imaging in the near-infrared in vivo. The luminescence efficiencies of single carbon nanotubes excited via various excitation strategies were compared and optimized for tissue imaging (e.g., targeting various excitonic transitions and through upconversion). The effects of tissue scattering, absorption, autofluorescence, and temperature increase induced by excitation light were systematically examined [1]. Using carbon nanotube tracking, we revealed the hidden structure and viscoelastic properties of the extracellular space of brain slices [2]. Local morphological and viscosity maps of the extracellular space of brain acute slices were reconstructed. A diversity of extracellular space dimensions down to ~40 nm and local viscosity maps were obtained. The rheological properties of the extracellular space are affected by chemical alterations of the extracellular matrix of the brains of live animals. Interestingly, these alterations are local and highly inhomogeneous in space. Probing the viscoelastic properties of the extracellular space is paramount to understand the spatiotemporal dynamics that regulate the cellular mechanisms ultimately influencing fundamental aspects of cell biology. These technological advances constitute the first milestone to generate super-resolution microscopy applications in the near-infrared to investigate live biological samples in situ.

References:

(1) Danné N* & Godin AG* et al. (2018) Comparison of the resonant excitations and upconversion luminescence of individual carbon nanotubes for biological tissue studies.

ACS Photonics 5 (2) 359-364. *ND and AGG contributed equally to this work.

(2) Godin AG et al. (2017) Single-nanotube tracking reveals the nanoscale organization of the extracellular space in the live brain.

Nature Nanotechnology 12 (3) 238-24.
(Invited) Decapyrrylcorannulene Buckyhands
Authors: Xie Su-Yuan , Zhang Qianyan , Yang Shangfeng
Published: May 2020

To mimic the smart molecular ‘hands’ for self-adaptably cradling various buckyballs in a (+)hand-ball-hand(-) mode, a decapyrrylcorannulene molecule having a concave corannulene and ten flexible electron-rich pyrryl groups has been synthesized by a facile metal-free catalytic Ullmann reaction under mild conditions. The usefulness of the as-synthesized Buckyhands was exemplified by crystallographic identification of tens buckyball structures representing pristine, exohedral, endohedral, dimeric and hetero-derivatization. The pyrryl groups twist with varying dihedral angles to adjust the interaction between decapyrrylcorannulene and fullerene, that is theoretically revealed to contribute more than the bowl-shaped palm of the corannulene in holding the buckyball structures.
(Invited) Novel Structured Carbon Materials Under High Pressure
Authors: LIU Bingbing
Published: May 2020

Design and synthesis of new carbon materials have been attracting intensive attention due to their application in various fields. The study of carbon nano materials under high pressure provides us a very effective method to the creation of new carbon materials, especially superhard material which is hardly discovered at ambient condition because of the appearance of nanometer scale size effect and the novel high pressure behavior. Deeply understanding those unusual high pressure structures and physical phenomena also unveils new aspects of the intrinsic physics of nanomaterials. Fullerene, for example C60 is an important member and a representative zero-dimensional nano material in carbon family which has twice as much bulk modulus as diamond. It provides us an ideal carbon source to study novel phase and design new carbon materials induced by high pressure. In this presentation, several examples on high pressure induced novel structural phase transition in recently studied typical nano-confined fullerene will be outlined, including unique long range ordered crystal with amorphous nano clusters as building blocks (OACC) in solvated C60 and C70 crystals which brings new physical insight to understand order and disorder concept and new approach to design superhard carbon materials, a new carbon allotrope with a fully
sp

3 bonded monoclinic structure (termed V carbon) from compressed C70 inside of single wall nanotubes (C70 peapod). These findings present a new strategy for constructing new carbon material with application of high pressure and nano-carbon material as building blocks.
(Invited) Pyridine-Functionalized Fullerene Additive Enabling Coordination Interactions with CH3NH3PbI3 Perovskite Towards Highly Efficient Bulk Heterojunction Solar Cells
Authors: Chen Muqing , Yang Shangfeng
Published: May 2020

Incorporating n-type fullerene derivatives into the perovskite layer affording bulk heterojunction (BHJ) perovskite solar cells (PSCs) is an effective strategy to passivate trap states, consequently reducing the current–voltage hysteresis and improving the device performance. Herein, we report the synthesis of a novel pyridine-functionalized fullerene derivative (C60-PyP) via a 1,3-dipolar cycloaddition reaction, and the unambiguous determination of its molecular structure by X-ray single crystal diffraction. Upon incorporating C60-PyP as an additive with an optimized doping ratio of 0.13 wt% into the CH3NH3Pbl3 (MAPbI3) perovskite precursor, the regular-structure bulk heterojunction PSC devices exhibit a best power conversion efficiency (PCE) of 19.82%, which is dramatically enhanced relative to that of the control devices (17.61%). The C60-PyP additive provides heterogeneous nucleation sites, leading to the decrease of the nucleation Gibbs free energy and consequently enlarged grain size and improved crystallization of the MAPbI3 perovskite film. Besides, incorporation of C60-PyP results in enhanced crystalline orientation as confirmed by grazing-incidence X-ray diffraction (GIXRD) measurements. Meanwhile, the coordination interaction between the N atom of the pyridine moiety within C60-PyP and the Pb2+ ion within MAPbl3 leads to the passivation of the trap states of the perovskite layer, jointly contributing to the improved device performance and markedly suppressed current–voltage hysteresis. Moreover, the ambient stability of the devices is improved upon C60-PyP incorporation due to the hydrophobic nature of the C60-PyP molecule, which presumably resides at the grain boundaries.
(Invited) Magnetism and Electrochemistry of Fullerene-Based Composites
Authors: Wang Xiao , Dong Peipei , Feng Yongqiang
Published: May 2020

Endohedral metallofullerenes (EMFs), a negatively sp
2-hybridized spherical carbon surface containing alternating hexagons and pentagons doped with metal ion(s) or cluster inside, have attracted more and more interests owing to their unique nesting structures and alluring chemical/physical properties. Herein, we will discuss several typical spin-active endohedral metallofullerenes. To steer the electron spin of paramagnetic fullerene molecules, a solid-state spin system was constructed via encapsulating paramagnetic fullerenes into the pores of metal-organic frameworks (MOFs) forming a EMF/MOF compostie, and an axisymmetric paramagnetic property was found. This kind of solid spin system can be used as a probe for nanoscale nuclear magnetic resonance or for motion imaging of a single biomolecule.

Besides, as a representative allotrope of carbon, fullerene-based composite also exhibit fascinating electrochemistry, e.g., serving as electrocatalyst. In this work, a novel hybrid electrocatalyst comprising fullerene carbon dot (FQD)-decorated cobalt nickel layered double hydroxide (CoNi-LDH) nanosheets anchored on porous nickel foam (NF) is elaborately fabricated. The obtained FQD/CoNi-LDH/NF exhibits superior electrocatalytic activity for hydrogen and oxygen evolution as well as urea oxidation under ambient atmosphere. Both experiment and density functional theory (DFT) calculations demonstrate that the charge transfer from FQD to CoNi-LDH could account for the excellent catalytic performance of the newly-synthesized catalyst, and the decorated FQD finely modulates the electronic structure of CoNi-LDH, favoring the adsorption of active hydrogen atom, and thus promote the catalytic process. The present work would provide useful guidance for designing and developing fullerene-based electrocatalysts for hydrogen production.
(Invited) Water-Soluble C60, C70 and M3N@C80 Derivatives for Biocompatible Materials
Authors: Yamakoshi Yoko , Liosi Korinne , Semivrazhskaya Olesya
Published: May 2020

For the biological application of fullerenes (C60, C70 and M3N@C80), highly water-soluble derivatives and complexes were prepared using two types of biocompatible polymers (PEG and poly(vinylpyrrolidone) (PVP)). For the preparation of derivatives, Prato reaction of each fullerene was used to obtain the precursor molecule and followed by the conjugation with the polymers. The prepared water-soluble materials were subjected to the test for photo induced reactive oxygen species (ROSs such as 1O2, O2•–, and •OH) and DNA cleavage to show the potential availability as photosensitizers in photodynamic therapy. Interestingly, there were some trend found in the generation of ROSs via type I electron transfer pathway or type II energy transfer pathway dependent on the fullerene cores and way of functionalizations (derivatization or complexation). The detail of the results will be presented in the meeting.
(Invited) Visualizing the Dynamics of Metallofullerenes with Variable Temperature Single Crystal X-Ray Diffraction
Authors: Liu Fupin , Spree Lukas , Popov Alexey A.
Published: May 2020

The empty interior space of fullerenes is ready to hold atoms/clusters to become endohedral fullerenes. Metal ions can be encapsulated in various fullerene cages, known as metallofullerenes. The interplay between the encapsulated metal ions and the fullerene cage carbon atoms is fundamental to understanding these molecules. Recently, we succeeded on the visualization of the dynamics of Dy2@Ih
(7)-C80-CH2Ph in the crystal lattice1 as well as M3N@Ih
(7)-C80 (M3N = Ho2LuN or Lu3N) in the crystal lattice of co-crystals with nickel octaethylporphyrin2 by variable temperature X-ray diffraction, see the following figure for the comparison of the equivalent atomic displacement parameters of heavy atoms. In this contribution, the details of the observed temperature dependent dynamics of the metallofullerenes will be discussed.

1. Liu, F.; Velkos, G.; Krylov, D. S.; Spree, L.; Zalibera, M.; Ray, R.; Samoylova, N. A.; Chen, C.-H.; Rosenkranz, M.; Schiemenz, S.; Ziegs, F.; Nenkov, K.; Kostanyan, A.; Greber, T.; Wolter, A. U. B.; Richter, M.; Büchner, B.; Avdoshenko, S. M.; Popov, A. A., Air-stable redox-active nanomagnets with lanthanide spins radical-bridged by a metal–metal bond. Nat. Commun.
2019,
10, 571.

2. Liu, F.; Spree, L., Molecular Spinning Top: Visualizing the Dynamics of M3N@C80 with Variable Temperature Single Crystal X-ray Diffraction. Chem. Commun.
2019,
55, 13000-13003.

Figure 1
Erythropoietin-producing hepatocellular receptor A7 restrains estrogen negative feedback of luteinizing hormone via ephrin A5 in the hypothalamus of female rats
Authors: Li Shang , Zhai Junyu , Xu Bing , Liu Jiansheng , Chu Weiwei , Wang Dongshuang , Geng Xueying , Chen Zi-Jiang , Du Yanzhi
Published: May 2020

We have previously shown that systemic injection of erythropoietin-producing hepatocellular receptor A7 (EPHA7)-Fc raises serum luteinizing hormone (LH) levels before ovulation in female rats, indicating the induction of EPHA7 in ovulation. In this study, we aimed to identify the mechanism and hypothalamus-pituitary-ovary (HPO) axis level underlying the promotion of LH secretion by EPHA7. Using an ovariectomized (OVX) rat model, in conjunction with low-dose 17β-estradiol (E2) treatment, we investigated the association between EPHA7-ephrin (EFN)A5 signaling and E2 negative feedback. Various rat models (OVX, E2-treated OVX, and abarelix treated) were injected with the recombinant EPHA7-Fc protein through the caudal vein to investigate the molecular mechanism underlying the promotion of LH secretion by EPHA7. Efna5 was observed strongly expressed in the arcuate nucleus of the female rat by using RNAscope in situ hybridization. Our results indicated that E2, combined with estrogen receptor (ER)α, but not ERβ, inhibited Efna5 and gonadotropin-releasing hormone 1 ( Gnrh1) expressions in the hypothalamus. In addition, the systemic administration of EPHA7-Fc restrained the inhibition of Efna5 and Gnrh1 by E2, resulting in increased Efna5 and Gnrh1 expressions in the hypothalamus as well as increased serum LH levels. Collectively, our findings demonstrated the involvement of EPHA7-EFNA5 signaling in the regulation of LH and the E2 negative feedback pathway in the hypothalamus, highlighting the functional role of EPHA7 in female reproduction.
Efficiency of Two-Stage Technological Innovation in High Patent-Intensive Industries That Considers Time Lag: Research Based on the SBM-NDEA Model
Authors: Zou Junzhong , Chen Wei , Peng Nan , Wei Xuan
Published: May 2020

Considering time lag and accumulation of inputs and outputs, this paper adopts the superefficiency data envelopment analysis (DEA) model to study the technological innovation efficiency of high patent-intensive industries using panel data from 2007 to 2017. Given the characteristics and the actual circumstances of the industries, the innovation process is divided into two stages, and an input-output indicator system is established. The results show that the overall innovation efficiency level of high patent-intensive industries in China is increasing. However, the R&D achievements in technology are not quickly applied or sufficiently transformed.
Adaptability of Kinetic Parameters to a Narrow Speed Range in Healthy Free-Moving Cats
Authors: Liu Congzhen , Wang Guolin , Zhou Haichao , Mei Ye , Asafo-Duho Bentil M. K.
Published: May 2020

Ground reaction force and impulse measurement is an established method for assessing the physical condition and efficacy of treatment for some animals. The primary aim of this study was to quantify the kinetic parameters of the limbs of healthy cats at different speeds. The second aim was to determine the explicit relationship between the kinetic parameters and speed. Peak vertical force (PVF), vertical impulse (VI), stance phase duration (SPD), and paw contact area (PCA) of each limb (forelimb, F; hindlimb, H) of seven clinically healthy, client-owned cats were recorded in the speed interval of 0.5–2.5 m/s. The cats were encouraged to pass by a pressure-sensitive walkway with different speeds. The results revealed that there were no significant differences in any of the tested parameters between the left and right forelimbs and the left and right hindlimbs. Means and regression formulas of the kinetic parameters with speed were obtained. It was evident that PVF-F and PVF-H increased linearly with speed, while VI-F and VI-H decreased exponentially. SPD-F was practically equal to SPD-H and exponentially decreased with speed. PCA-F increased linearly with speed, and PCA-H was almost invariable. Pressure-sensitive walkway is a suitable and convenient equipment for assessing the kinetic parameters of cats. Variation of these kinetic parameters with speed can be explained by the functional difference for forelimb-dominant and hindlimb-driven.
Factors Associated with Prehospital Delay among Men and Women Newly Experiencing Acute Coronary Syndrome: A Qualitative Inquiry
Authors: Hadid Lourance A. Al , Al Barmawi Marwa , Al Hmaimat Nathira Abdelqader Ahmad , Shoqirat Noordeen
Published: May 2020

Background. Delaying seeking health care for patients with acute coronary syndrome (ACS) causes high mortality and morbidity with variations among men and women regarding reasons for this delay. Objectives. This study explored factors associated with prehospital delay among men and women experiencing acute coronary syndrome for the first time in Jordan. Methods. 35 men and 33 women with ACS admitted and treated at the coronary and postcoronary care units. Results. Themes emerging from the data are knowledge about ACS, the resources related to health care, and concerns around family wellbeing. Owing to the traditional roles of men and women within the family, women felt responsible for maintaining the family, assisting in the financial conditions, and supporting family coherence by delaying hospitalization. Men were worried about the structural safety and maintenance of the family. Conclusion and Implications. Prehospital delay is common among first-timer ACS patients from both sexes, and thus, increasing awareness about ACS among the public from all age groups is necessary. Availability of specialized health care centers and equity in health care services are vital to improve public confidence in these health care settings and health outcomes.
Comparison of Instantaneous Wave-Free Ratio (iFR) and Fractional Flow Reserve (FFR) with respect to Their Sensitivities to Cardiovascular Factors: A Computational Model-Based Study
Authors: Ge Xinyang , Liu Youjun , Yin Zhaofang , Tu Shengxian , Fan Yuqi , Vassilevski Yuri , Simakov Sergey , Liang Fuyou
Published: May 2020

While coronary revascularization strategies guided by instantaneous wave-free ratio (iFR) are, in general, noninferior to those guided by fractional flow reserve (FFR) with respect to the rate of major adverse cardiac events at one-year follow-up in patients with stable angina or an acute coronary syndrome, the overall accuracy of diagnosis with iFR in large patient cohorts is about 80% compared with the diagnosis with FFR. So far, it remains incompletely understood what factors contribute to the discordant diagnosis between iFR and FFR. In this study, a computational method was used to systemically investigate the respective effects of various cardiovascular factors on FFR and iFR. The results showed that deterioration in aortic valve disease (e.g., regurgitation or stenosis) led to a marked decrease in iFR and a mild increase in FFR given fixed severity of coronary artery stenosis and that increasing coronary microvascular resistance caused a considerable increase in both iFR and FFR, but the degree of increase in iFR was lower than that in FFR. These findings suggest that there is a high probability of discordant diagnosis between iFR and FFR in patients with severe aortic valve disease or coronary microcirculation dysfunction.
A New Feature Selection Method for Text Classification Based on Independent Feature Space Search
Authors: Liu Yong , Ju Shenggen , Wang Junfeng , Su Chong
Published: May 2020

Feature selection method is designed to select the representative feature subsets from the original feature set by different evaluation of feature relevance, which focuses on reducing the dimension of the features while maintaining the predictive accuracy of a classifier. In this study, we propose a feature selection method for text classification based on independent feature space search. Firstly, a relative document-term frequency difference (RDTFD) method is proposed to divide the features in all text documents into two independent feature sets according to the features’ ability to discriminate the positive and negative samples, which has two important functions: one is to improve the high class correlation of the features and reduce the correlation between the features and the other is to reduce the search range of feature space and maintain appropriate feature redundancy. Secondly, the feature search strategy is used to search the optimal feature subset in independent feature space, which can improve the performance of text classification. Finally, we evaluate several experiments conduced on six benchmark corpora, the experimental results show the RDTFD method based on independent feature space search is more robust than the other feature selection methods.
Adaptive Predefined Performance Neural Control for Robotic Manipulators with Unknown Dead Zone
Authors: Shao Shifen , Zhang Kaisheng , Li Jun , Wang Jirong
Published: May 2020

This paper proposes an adaptive predefined performance neural control scheme for robotic manipulators in the presence of nonlinear dead zone. A neural network (NN) is utilized to estimate the model uncertainties and unknown dynamics. An improved funnel function is designed to guarantee the transient behavior of the tracking error. The proposed funnel function can release the assumption on the conventional funnel control. Then, an adaptive predefined performance neural controller is proposed for robotic manipulators, while the tracking errors fall within a prescribed funnel boundary. The closed-loop system stability is proved via Lyapunov function. Finally, the numerical simulation results based on a 2-DOF robotic manipulator illustrate the control effect of the presented approach.
Direction-of-Arrival Estimation for 2D Coherently Distributed Sources with Nested Array Based on Matrix Reconstruction
Authors: Xiao Yu , Wu Tao , Li Yiwen , Ma Xinping , Huang Yijie
Published: May 2020

This paper has made proposition of a nested array and an estimation algorithm for direction-of-arrival (DOA) of two-dimensional (2D) coherently distributed (CD) sources. According to the difference coarray concept, double parallel hole-free virtual uniform linear arrays are generated by virtue of vectorization operation on cross-correlation matrices of subarrays. Sensor coordinates of virtual arrays are derived. Rational invariance relationships of virtual arrays are derived. According to the rotational invariance relationships, matrices satisfying rotation invariance are constructed by extracting and regrouping the receive vectors of the virtual arrays, and then an estimation of signal parameters via rotational invariance techniques- (ESPRIT-) like framework on matrix reconstruction is deduced. Optimal configuration of the nested array as well as computational complexity are analyzed. Without pair matching, the proposed method can resolve more sources than the sensor number. Simulation outcomes indicate that the proposed method tends to have a better performance as compared to the traditional uniform arrays that have similar number of sensors.
Urethral Diverticulum following Polypropylene Mesh Midurethral Slings: A Literature Review
Authors: Pacer Elizabeth , Duenas-Garcia Omar Felipe , Hota Lekha , Hornsby Kristan , Shapiro Robert
Published: May 2020

Aims. It is currently unknown whether an association exists between polypropylene mesh and urethral diverticulum formation following placement of polypropylene midurethral slings (MUS) for the treatment of stress urinary incontinence (SUI). We aimed to examine the literature associating MUS with the occurrence of urethral diverticula. Methods. Multiple online research databases, including PubMed, Google Scholar, EBSCOhost, and the Cochrane Library, were searched, from January 2019 to February 2019, for evidence related to the occurrence of urethral diverticula following polypropylene MUS procedures. Results. Four case reports were published demonstrating the occurrence of urethral diverticula following the use of polypropylene mesh for surgical treatment of SUI. Subjects of these cases were menopausal and had an elevated body mass index (BMI), recurrent urinary tract infections (UTIs), autoimmune conditions, or prior pelvic floor surgeries. A thorough urologic workup, including imaging prior to sling placement, was not always performed. Conclusion. No clear association exists between polypropylene MUS placement and subsequent urethral diverticulum formation. Factors that diminish polypropylene mesh biocompatibility include elevated BMI, menopause, recurrent UTIs, prior pelvic surgeries, and preexisting medical conditions. Symptoms associated with urethral diverticula should prompt a complete urologic workup prior to MUS placement.
The Efficacy of Concentrated Growth Factor in the Healing of Alveolar Osteitis: A Clinical Study
Authors: Kamal Aqsa , Salman Basheer , Abdul Razak Noor Hayati , Qabbani Ali Al , Samsudin A. R.
Published: May 2020

Background. A dry socket also referred to as alveolar osteitis (AO) is a common postoperative complication following tooth extraction, due to the disruption of the clot within the wound. This study aimed to evaluate the efficacy of concentrated growth factor (CGF) in the healing of alveolar osteitis following tooth extraction. Methods. The study was conducted at University Dental Hospital Sharjah, UAE. Patients undergoing tooth extraction at the oral surgery clinic were advised to return immediately if they suffer from pain. Over the following first week after tooth extraction, patients who reported pain symptoms were recalled and all dry sockets were identified. The patients were divided into two groups. Group I patients received conventional treatment with socket curettage and saline irrigation only, while in group II CGF was inserted into the socket. Both groups were observed for pain score and quantification of granulation tissue formation. Results. A total of 40 dry socket patients, aged between 18 and 60 years, from a total of 1,250 patients, were included in the study. 30 patients were given conventional treatment while another 10 patients were given CGF. Patients who received CGF had a pain score of 7–10 at presentation, and the pain score dropped to 0–3 on day 4 and further improved to 0-1 on day 7 (p=0.001). Granulation tissue formation appeared in the conventional group I on day 7 while the CGF group II showed earlier granulation tissue formation by day 4 (p=0.001). The posttreatment pain score is inversely proportional to the amount and rate of granulation tissue formation in the socket. Conclusion. The study suggests that delivery of CGF into a dry socket helps relieve pain and expedite the wound healing process as shown by a statistically much lower pain score and earlier and more rapid formation of granulation tissue when compared to the conventional alveolar osteitis therapy.
Clinical and Genetic Analyses of 38 Chinese Patients with Peutz‐Jeghers Syndrome
Authors: Wu Bo-Da , Wang Yong-Jun , Fan Liang-Liang , Huang Hui , Zhou Peng , Yang Mei , Shi Xiao-Liu
Published: May 2020

Background. Peutz‐Jeghers syndrome (PJS) is a rare autosomal dominant inherited disease caused by a germline mutation in the STK11 gene. It is characterized by mucocutaneous pigmentation, gastrointestinal hamartomatous polyps, and cancer predisposition. Aims. We aimed to summarize the main clinical and genetic features of Chinese PJS patients and assessed the genotype‐phenotype correlations. Methods. Thirty‐eight patients clinically diagnosed with Peutz‐Jeghers syndrome were included in this study from 2016 to 2019. Combined direct sequencing and multiplex ligation‐dependent probe amplification tests were used to detect germline heterogeneous STK11 mutations. RNA sequencing was performed in polyps of PJS patients and control groups to evaluate the difference in expression of STK11. The genotype‐phenotype correlations were calculated by Kaplan‐Meier analyses. Results. All 26 probands and 12 affected relatives had germline heterogeneous STK11 mutations among which 8 variants were novel. Individuals with missense mutations had their first surgery and other symptoms significantly later than individuals with null mutations. Conclusion. This study expanded the spectrum of STK11 gene mutations and further elucidated individuals with null mutations of STK11 typically had an earlier onset of PJS symptoms and needed earlier management.
Identification of Aircraft Wake Vortex Based on SVM
Authors: Pan Weijun , Wu Zhengyuan , Zhang Xiaolei
Published: May 2020

The aircraft wake vortex has important influence on the operation of the airspace utilization ratio. Particularly, the identification of aircraft wake vortex using the pulsed Doppler lidar characteristics provides a new knowledge of wake turbulence separation standards. This paper develops an efficient pattern recognition-based method for identifying the aircraft wake vortex measured with the pulsed Doppler lidar. The proposed method is outlined in two stages. (i) First, a classification model based on support vector machine (SVM) is introduced to extract the radial velocity features in the wind fields by combining the environmental parameters. (ii) Then, grid search and cross-validation based on soft margin SVM with kernel tricks are employed to identify the aircraft wake vortex, using the test dataset. The dataset includes wake vortices of various aircrafts collected at the Chengdu Shuangliu International Airport from Aug 16, 2018, to Oct 10, 2018. The experimental results on dataset show that the proposed method can identify the aircraft wake vortex with only a small loss, which ensures the satisfactory robustness in detection performance.
Smoking-Induced Inhibition of Number and Activity of Endothelial Progenitor Cells and Nitric Oxide in Males Were Reversed by Estradiol in Premenopausal Females
Authors: Shao Yijia , Luo Liang , Ren Zi , Guo Jiayi , Xiao Xingxing , Huang Jiana , Zeng Haitao , Zhan Hong
Published: May 2020

Objectives. The number and activity of circulating EPCs were enhanced in premenopausal women contrast to postmenopausal females and age-matched males. Here, we investigated whether this favorable effect exists in premenopausal women and age-matched men with cigarette smoking.Methods. In a cross-sectional study, the number and activity of circulating EPCs and nitric oxide production (NO) as well as flow-mediated vasodilation (FMD) in both premenopausal women and age-matched men with or without cigarette smoking were studied.Results. Compared with age-matched men with or without smoking, the number and function of circulating EPCs as well as NO level in premenopausal women were obviously higher than that in the former and not affected by smoking. The number and function of circulating EPCs as well as NO level in male smokers were shown to be the most strongly inhibited. Furthermore, there was significant correlation between EPC number and activity, plasma NO level, and NO secretion by EPCs and FMD.Conclusions. Estradiol was deemed to play an important role in enhancing the number and activity of EPCs and NO production in premenopausal women even when affected by smoking, which may be the important mechanisms underlying vascular protection of estradiol in premenopausal women, but not in age-matched men.
“All Our Wisdom is Stored in the Trees” - Degrading BCR-ABL with Berberis Vulgaris
Authors: Elf Shannon Elisabeth
Published: May 2020

Treating BCR-ABL–positive chronic myeloid leukemia remains impeded by the development of clinical resistance to imatinib. It has been demonstrated that berberine, a plant alkaloid, has activity against imatinib-resistant BCR-ABL mutants by inducing autophagic degradation of BCR-ABL, thereby preventing the acquisition of drug-resistant mutations.

See related article by Yin et al., p. 4040
A Novel Model of Balloon Angioplasty Injury in Rat Arteriovenous Fistula
Authors: Somarathna Maheshika , Isayeva-Waldrop Tatyana , Al-Balas Alian , Guo Lingling , Lee Timmy
Published: May 2020

Background: There are very few animal models of balloon angioplasty injury in arteriovenous fistula (AVF), hindering insight into the pathophysiologic processes following angioplasty in AVF. The objective of the study was to develop and characterize a rat model of AVF angioplasty injury. Methods: Balloon angioplasty in 12- to 16-week-old Sprague-Dawley rats was performed at the arteriovenous anastomosis 14 days post-AVF creation with a 2F Fogarty balloon catheter. Morphometry and protein expression of endothelial nitric oxide synthase (eNOS), monocyte-chemoattractant protein-1 (MCP-1), alpha-smooth muscle actin (α-SMA), CD68 (macrophage marker), and collagen expression in AVFs with and without angioplasty were assessed. Results: In AVFs with angioplasty versus without angioplasty: (1) angioplasty increased AVF-vein and artery intimal hyperplasia, (2) angioplasty decreased eNOS protein expression in AVF-vein and artery at 21 days post-AVF creation and remained decreased in the AVF-vein angioplasty group at 35 days, (3) angioplasty increased AVF-vein and artery α-SMA expression within the intimal region at 35 days, (4) angioplasty increased the expression of AVF-vein MCP-1 at 21 days and CD68 at 21 and 35 days, and (5) angioplasty increased AVF-vein and artery collagen expression at 35 days. Conclusion: Our findings describe a reproducible rat model to better understand the pathophysiologic mechanisms that ensue following AVF angioplasty.
Complete Superior and Inferior Vena Cava Obstruction Associated with Systemic-to-Pulmonary Venous Shunts in a Young Female with Heterozygous Prothrombin G20210A Gene Mutation
Authors: Ahmed Ashraf Omer Elamin , Elfert Khaled A. , Mahfouz Ahmed E. , Othman Fahmi S. , Elgassim Lenah A. , Yassin Mohamed A.
Published: May 2020

Complete superior vena cava (SVC) and inferior vena cava (IVC) obstruction is not uncommon and most commonly associated with malignancy. The risk increases in patients with central lines and hypercoagulable states such as with malignancy, thrombophilia, or use of oral contraceptive pills. According to our knowledge, complete SVC and IVC obstruction associated with systemic-to-pulmonary venous shunts in patients with prothrombin G20210A gene mutation has not been reported in the literature. Here we report the case of a 34-year-old female with complete SVC and IVC obstruction presenting with oxygen desaturation and shortness of breath due to systemic-to-pulmonary venous shunts. The unusual collateral pathway was secondary to SVC obstruction. The patient was managed conservatively, and she remained stable.
Drug-Induced Anaphylaxis: An Update on Epidemiology and Risk Factors
Authors: Regateiro Frederico S. , Marques Maria Luís , Gomes Eva Rebelo
Published: May 2020

Drug hypersensitivity is one of the most frequent causes of anaphylaxis, particularly in adults and in hospitalized patients. Drug-induced anaphylaxis (DIA) is also associated with more severe outcomes than other anaphylaxis triggers, and drugs are responsible for the majority of deaths due to anaphylaxis. We here review the current knowledge on the incidence, prevalence, drugs involved, mortality, and mortality risk factors for DIA. The incidence of both anaphylaxis and DIA seems to be increasing worldwide. Antibiotics and analgesics are the most frequently reported triggers of DIA. However, the importance of other drug groups should be taken into account, especially in particular settings (e.g., peri-operative and oncology). The identification of risk factors, geographical variables, and drugs associated with higher risk for DIA may improve the outcomes of this entity.
Post-Neoadjuvant Gemcitabine and Cisplatin with Regional Hyperthermia for Patients with Triple-Negative Breast Cancer and Non-pCR after Neoadjuvant Chemotherapy: A Single-Institute Experience
Authors: Stoetzer Oliver , Di Gioia Dorit , Issels Rolf Dieter , Abdel-Rahman Sultan , Mansmann Ulrich , Lindner Lars Hartwin , Gluz Oleg , Würstlein Rachel , Braun Michael , Hamann Moritz , Edler von Koch Franz , Harbeck Nadia , Salat Christoph
Published: May 2020

Background: Patients with triple-negative primary breast cancer (TNBC) who have residual invasive carcinoma after neoadjuvant chemotherapy have poor prognosis. Proven adjuvant approaches to reduce the risk of recurrence and improve outcome in patients with non-pathological complete response (non-pCR) are limited. Methods: From our institutional registry, a consecutive case series of patients with operable, unilateral, primary invasive noninflammatory early TNBC of stage I-IIIB and pathologically verified residual cancer cells (no pathological complete response) after neoadjuvant chemotherapy underwent adjuvant treatment with gemcitabine plus cisplatin combined with regional hyperthermia. For quality assurance, we analyzed feasibility, efficacy, and toxicity of all treated patients. Outcome was evaluated for the entire group of patients as well as for the subgroups of patients with or without lymph node involvement at baseline (cN0/ cN+). Results: From August 2012 to January 2019, we offered this treatment to 53 patients at our center as part of routine care. The median follow-up was 38 months. The majority of patients (64.2%) had cT2 tumors at baseline. Twenty-four patients (45%) were clinically node positive as evaluated by sonography. Thirty-nine patients (74%) had grade 3, and 14 patients (26%) had grade 2 tumors. Forty-one patients (76%) showed a regression grade 1 according to Sinn. Patients received a median of six treatment cycles of gemcitabine and cisplatin (range 1–6) combined with 12 applications of regional hyperthermia (median 12, range 2–12). Disease-free survival (DFS) at 3 years was 57.5%. In patients with no lymph node involvement at baseline (cN0), DFS at 3 years was significantly higher than in initially node-positive (cN+) patients (80 vs. 31%; p = 0.001). Overall survival (OS) at 3 years was 81.6%. In patients with no lymph node involvement at baseline (cN0), OS at 3 years was significantly higher than in node-positive (cN+) patients (93 vs. 70.4%; p = 0.02). Overall, grade 3/4 toxicities were leukopenia (38%), thrombocytopenia (4%), and anemia (4%). Conclusion: After standard neoadjuvant chemotherapy containing anthracycline plus cyclophosphamide followed by taxanes, addition of adjuvant gemcitabine plus cisplatin in combination with regional hyperthermia was safe and effective in TNBC patients with non-pCR.
Molecular Cytogenetic Analysis of Karyotype and Y Chromosome Conservation in Species of the Genus Talpa (Insectivora)
Authors: Gutierrez Juana , Aleix-Mata Gael , Marchal Juan A. , Arroyo María , Castiglia Riccardo , Sánchez Antonio
Published: May 2020

The Talpidae family has a highly stable karyotype. Most of the chromosome studies in this mammal group, however, employed classical cytogenetic techniques. Molecular cytogenetic analyses are still scarce and, for example, no repeated DNA sequences have been described to date. In this work, we used sequence analysis, chromosomal mapping of a LINE1 retroelement sequence, as well as chromosome painting with a whole Y chromosome probe of T. occidentalis to compare the karyotypes of 3 species of the genus Talpa (T. occidentalis, T. romana, and T. aquitania). Our results demonstrate that in Talpa genomes LINE1 sequences are widely distributed on all chromosomes but are enriched in pericentromeric C-band-positive regions. In addition, these LINE1 accumulate on the Y chromosomes of the 3 Talpa species regardless of their euchromatic or heterochromatic condition. Chromosome painting shows that the Y chromosomes in these 3 species are highly conserved. Interestingly, they share sequences with heterochromatic blocks on chromosome pairs 14 and 16 and, to a lesser degree, with the pericentromeric regions of other autosomes. Together, our analyses demonstrate that the repetitive DNA content of chromosomes from Talpa species is highly conserved.
Caracterização dos contaminantes do minério de ferro do depósito mineral da Serra do Sapo, Conceição do Mato Dentro, Minas Gerais
Authors: Morais Fernando Prudencio , Silva Rosaline Cristina Figueiredo e , Rosiére Carlos Alberto , Dias Geraldo Sarquis
Published: May 2020

Os itabiritos do depósito mineral da Serra do Sapo estão localizados na região da Serra do Espinhaço Meridional e são descritos como parte da Formação Serra do Sapo, unidade superior do Grupo Serra da Serpentina, e estão sobrepostos aos xistos e aos filitos da Formação Meloso. Formações ferríferas com alto teor de Al e P ocorrem no contato com metassedimentos da unidade basal. Esses contatos são transicionais e geram uma rocha bandada, com níveis milimétricos a centimétricos contendo grande concentração de óxido de ferro. Essa litologia tem textura sedosa e ocorre sempre decomposta, sendo descrita como hematita-quartzo-mica xistos ou classificada como itabirito com alto teor de contaminantes (IFX). A classificação dos itabiritos é feita de acordo com o grau de decomposição intempérica da rocha. Formações ferríferas bandadas classificadas como itabiritos (IT), rocha sã, e que também apresentam altos teores de P como contaminante, são classificadas como itabirito com alto teor de fósforo (ITX). Estudos petrográficos identificaram muscovita, clorita e gibbsita como as principais fontes de Al para as amostras de IFX. Os altos teores de Al2O3 e P2O5 desses litotipos também são explicados pelo processo de formação supergênica, em que o espaço dos minerais lixiviados é preenchido por clorita e gibbsita. Para o ITX, os altos teores de P estão relacionados com minerais de apatita que ocorrem com maior frequência nesse litotipo. Dados geoquímicos de rocha total, quando normalizados ao Pos-Archean Australian Shale (PAAS), mostram que as amostras de IFX são enriquecidas em elementos terras raras leves (ETRL) se comparadas aos outros itabiritos. Essas amostras também são enriquecidas em elementos móveis como Ba e Sr. Isso indica que o enriquecimento
Aeromagnetometria e aerogamaespectrometria do Complexo Atuba e arredores, leste do estado do Paraná
Authors: Baldin Michelangelo Tissi , Salamuni Eduardo , Castro Luís Gustavo De
Published: May 2020

As rochas do Complexo Atuba afloram na porção leste do Estado do Paraná e compreendem a região sul do Cinturão Ribeira. Situam-se a norte do Terreno Luís Alves e estão enquadradas no Terreno Curitiba. O objetivo desta pesquisa foi definir as unidades geológicas e o arcabouço estrutural da área de trabalho, junto ao mapeamento de falhas, fraturas e diques. A pesquisa foi desenvolvida por meio de aeromagnetometria e aerogamaespectrometria. A primeira permitiu interpretar os traçados de lineamentos e estabelecer o arcabouço estrutural da área de estudo, porém não conseguiu separar de forma definida o Complexo Atuba do Grupo Açungui. As grandes zonas de cisalhamento definidas pela Zona de Cisalhamento (ZC) Lancinha-Cubatão e ZC Curitiba estão encobertas e mascaradas pelos diques básicos mesozoicos. Os lineamentos com direção NE-SW são escassos e correspondem às falhas e às fraturas observadas principalmente no domínio do Complexo Atuba e da Bacia Sedimentar de Curitiba. As orientações NW-SE aparecem em grande proporção e estão relacionadas às falhas e aos diques. O método gamaespectrométrico possibilitou observar  dispersão dos elementos K, Th e U, caracterizando as unidades litológicas e detectando a presença de intrusões ígneas. De acordo com esse método, foi possível identificar quatro domínios diferentes, formados pelo Complexo Atuba, pela Formação Capiru, pela Formação Guabirotuba e por granitos neoproterozoicos.
PKG1α Cysteine-42 Redox State Controls mTORC1 Activation in Pathological Cardiac Hypertrophy
Authors: Oeing Christian U. , Nakamura Taishi , Pan Shi , Mishra Sumita , Dunkerly-Eyring Brittany L. , Kokkonen-Simon Kristen M. , Lin Brian L. , Chen Anna , Zhu Guangshuo , Bedja Djahida , Lee Dong Ik. , Kass David A. , Ranek Mark J.
Published: May 2020

Rationale:

Stimulated PKG1α (protein kinase G-1α) phosphorylates TSC2 (tuberous sclerosis complex 2) at serine 1365, potently suppressing mTORC1 (mechanistic [mammalian] target of rapamycin complex 1) activation by neurohormonal and hemodynamic stress. This reduces pathological hypertrophy and dysfunction and increases autophagy. PKG1α oxidation at cysteine-42 is also induced by these stressors, which blunts its cardioprotective effects.

Objective:

We tested the dependence of mTORC1 activation on PKG1α C42 oxidation and its capacity to suppress such activation by soluble GC-1 (guanylyl cyclase 1) activation.

Methods and Results:

Cardiomyocytes expressing wild-type (WT) PKG1α (PKG1α
WT
) or cysteine-42 to serine mutation redox-dead (PKG1α
CS/CS
) were exposed to ET-1 (endothelin 1). Cells expressing PKG1α
WT
exhibited substantial mTORC1 activation (p70 S6K [p70 S6 kinase], 4EBP1 [elF4E binding protein-1], and Ulk1 [Unc-51-like kinase 1] phosphorylation), reduced autophagy/autophagic flux, and abnormal protein aggregation; all were markedly reversed by PKG1α
CS/CS
expression. Mice with global knock-in of PKG1α
CS/CS
subjected to pressure overload (PO) also displayed markedly reduced mTORC1 activation, protein aggregation, hypertrophy, and ventricular dysfunction versus PO in PKG1α
WT
mice. Cardioprotection against PO was equalized between groups by co-treatment with the mTORC1 inhibitor everolimus. TSC2-S1365 phosphorylation increased in PKG1α
CS/CS
more than PKG1α
WT
myocardium following PO. TSC2
S1365A/S1365A
(TSC2 S1365 phospho-null, created by a serine to alanine mutation) knock-in mice lack TSC2 phosphorylation by PKG1α, and when genetically crossed with PKG1α
CS/CS
mice, protection against PO-induced mTORC1 activation, cardiodepression, and mortality in PKG1α
CS/CS
mice was lost. Direct stimulation of GC-1 (BAY-602770) offset disparate mTORC1 activation between PKG1α
WT
and PKG1α
CS/CS
after PO and blocked ET-1 stimulated mTORC1 in TSC2
S1365A
-expressing myocytes.

Conclusions:

Oxidation of PKG1α at C42 reduces its phosphorylation of TSC2, resulting in amplified PO-stimulated mTORC1 activity and associated hypertrophy, dysfunction, and depressed autophagy. This is ameliorated by direct GC-1 stimulation.
Group-size preferences in a shoaling cichlid
Authors: Durrer Loris , Taborsky Michael , Frommen Joachim G.
Published: May 2020

Group size is an important criterion in social decisions. Accordingly, assessing quantities is common in many animals. In fishes, studies on numerical abilities focus on a limited range of species. Arguably, cichlids show the greatest variability of social patterns among vertebrates. Nevertheless, knowledge about their quantitative abilities is scarce. Here we use the Lake Tanganyika cichlid Lamprologus callipterus to scrutinize the quantitative abilities of fish in the context of shoaling. Females chose between different numbers of conspecifics, varying in absolute and relative number differences. In half of the trials both shoals were composed of familiar sisters, while all fish were unfamiliar non-kin in the other half. Test fish consistently preferred the larger of two shoals, irrespective of the ratios. Their activity differed significantly between familiarity/relatedness treatments, indicating recognition of this parameter. L. callipterus therefore has fine-tuned discrimination skills, adding to the evidence that quantitative abilities are widespread in fishes.
Revision of Angraecum sect. Perrierangraecum (Orchidaceae; Epidendroideae; Vandeae) for the Mascarenes, with a description of a new endemic species for Mauritius

Authors: PAILLER THIERRY , VERLYNDE SIMON , BYTEBIER BENNY , FLORENS F.B. VINCENT , BAIDER CLÁUDIA
Published: May 2020

While revising the genus Angraecum (Orchidaceae) for the Mascarenes, a new taxon endemic to Mauritius was identified and it is here described as Angraecum baiderae. More than 300 Angraecum specimens, including types, collected in the Mascarenes and Madagascar, and available at DBEV, G, K, KM, L, MARS, MAU, MO, P, REU, SEY, TEF, and TAN were studied to confirm the taxonomic status of this new taxon. Its conservation status was assessed as Endangered. Furthermore, this paper presents detailed descriptions, conservation status, and a key to all species of Angraecum sect. Perrierangraecum occurring in the Mascarenes.