bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimal location of water level sensors for monitoring mine water inrush based on the set covering model
Authors: Wu Qiang , Du Zhili , Zhao Yingwang , Xu Hua , Zhang Xiaoyan
Published: January 2021

Water inrush is one of the major mining disasters that may lead to numerous casualties. The development of information techniques makes it possible to monitor the occurrence and evolution of water inrush. Then, locating monitors for water inrush becomes a primary problem. This study presents a method of optimal location of water level sensors by constructing a set covering model. The monitoring scope of the water level sensor at each location in a given time is computed first based on the numerical simulation of water spreading along mine tunnels. In this simulation, the water inrush quantity is assigned using the mine drainage capability over which an accident may occur. Then the greedy algorithm is used to optimize the number and positions of water level sensors. As results, a mine water disaster can be monitored in the given time after it happened. The proposed method is then verified in the Beiyangzhuang coal mine in the North China. The results show that at least 22, 36, 42, 64 and 106 water level sensors are needed to monitor water disasters in the whole mine within 60, 30, 20, 10 and 5 min, respectively.
The influence of distance weight on the inverse distance weighted method for ore-grade estimation
Authors: Liu Zhan-Ning , Yu Xiao-Yan , Jia Li-Feng , Wang Yuan-Sheng , Song Yu-Chen , Meng Hai-Dong
Published: January 2021

In order to study the influence of distance weight on ore-grade estimation, the inverse distance weighted (IDW) is used to estimate the Ni grade and MgO grade of serpentinite ore based on a three-dimensional ore body model and related block models. Manhattan distance, Euclidean distance, Chebyshev distance, and multiple forms of the Minkowski distance are used to calculate distance weight of IDW. Results show that using the Minkowski distance for the distance weight calculation is feasible. The law of the estimated results along with the distance weight is given. The study expands the distance weight calculation method in the IDW method, and a new method for improving estimation accuracy is given. Researchers can choose different weight calculation methods according to their needs. In this study, the estimated effect is best when the power of the Minkowski distance is 3 for a 10 m × 10 m × 10 m block model. For a 20 m × 20 m × 20 m block model, the estimated effect is best when the power of the Minkowski distance is 9.
Bilateral vestibulopathy causes selective deficits in recombining novel routes in real space
Authors: Schöberl Florian , Pradhan Cauchy , Grosch Maximilian , Brendel Matthias , Jostes Florian , Obermaier Katrin , Sowa Chantal , Jahn Klaus , Bartenstein Peter , Brandt Thomas , Dieterich Marianne , Zwergal Andreas
Published: January 2021

The differential impact of complete and incomplete bilateral vestibulopathy (BVP) on spatial orientation, visual exploration, and navigation-induced brain network activations is still under debate. In this study, 14 BVP patients (6 complete, 8 incomplete) and 14 age-matched healthy controls performed a navigation task requiring them to retrace familiar routes and recombine novel routes to find five items in real space. [18F]-fluorodeoxyglucose-PET was used to determine navigation-induced brain activations. Participants wore a gaze-controlled, head-fixed camera that recorded their visual exploration behaviour. Patients performed worse, when recombining novel routes (p < 0.001), whereas retracing of familiar routes was normal (p = 0.82). These deficits correlated with the severity of BVP. Patients exhibited higher gait fluctuations, spent less time at crossroads, and used a possible shortcut less often (p < 0.05). The right hippocampus and entorhinal cortex were less active and the bilateral parahippocampal place area more active during navigation in patients. Complete BVP showed reduced activations in the pontine brainstem, anterior thalamus, posterior insular, and retrosplenial cortex compared to incomplete BVP. The navigation-induced brain activation pattern in BVP is compatible with deficits in creating a mental representation of a novel environment. Residual vestibular function allows recruitment of brain areas involved in head direction signalling to support navigation.
Hepatitis C virus (HCV) diagnosis via microfluidics
Authors: Narayanamurthy Vigneswaran , Jeroish Z. E. , Bhuvaneshwari K. S. , Samsuri Fahmi
Published: January 2021

Several microfluidic techniques for HCV viral diagnosis.
Ultrafast excited-state dynamics of promising nucleobase ancestor 2,4,6-triaminopyrimidine
Authors: Rankine Conor D.
Published: January 2021

The ultrafast excited-state dynamics of 2,4,6-triaminopyrimidine (TAP) give rise to a short excited-state lifetime that is competitive with the lifetimes of the canonical pyrimidine nucleobases, affirming the promise of TAP as a plausible ancestor.
Enhanced performance of Mo2P monolayer as lithium-ion battery anode materials by carbon and nitrogen doping: a first principles study
Authors: Liu Xinghui , Lin Shiru , Gao Jian , Shi Hu , Kim Seong-Gon , Chen Zhongfang , Lee Hyoyoung
Published: January 2021

Simple carbon (nitrogen) doped Mo2P as promoting lithium-ion battery anode materials with extremely low energy barrier and high capacity.
Mn-Decorated CeO2 nanorod supported iron-based catalyst for high-temperature Fischer–Tropsch synthesis of light olefins
Authors: Wu Xian , Qian Weixin , Zhang Haitao , Han Zhonghao , Zhang Hewei , Ma Hongfang , Liu Dianhua , Sun Qiwen , Ying Weiyong
Published: January 2021

The synergistic effect between Mn and Ce can improve electrons transfer from Ce to Fe and the oxygen migration. The remarkable properties promote the dissociation of CO, suppress the hydrogenation, and improve the selectivity of light olefins.
Donor–acceptor covalent organic framework/g-C3N4 hybrids for efficient visible light photocatalytic H2 production
Authors: Lin Chenxiang , Han Chaozheng , Gong Lei , Chen Xin , Deng Jinxia , Qi Dongdong , Bian Yongzhong , Wang Kang , Jiang Jianzhuang
Published: January 2021

A donor–acceptor type covalent organic framework (COF) was used to construct TBTA/g-C3N4 hybrids for photocatalytic H2 evolution. Under visible light irradiation, the hybrids exhibited an optimized H2 evolution rate of 11.73 mmol g−1 h−1 without Pt.
Engineering the large pocket of an (S)-selective transaminase for asymmetric synthesis of (S)-1-amino-1-phenylpropane
Authors: Xie Youyu , Xu Feng , Yang Lin , Liu He , Xu Xiangyang , Wang Hualei , Wei Dongzhi
Published: January 2021

Amine transaminases offer an environmentally benign chiral amine asymmetric synthesis route.
Lowest aqueous picomolar fluoride ions and in vivo aluminum toxicity detection by an aluminum(iii) binding chemosensor
Authors: Das Monojit , Maity Debdeep , Acharya Tusar Kanta , Sau Sudip , Giri Chandan , Goswami Chandan , Mal Prasenjit
Published: January 2021

A water-soluble PET-based chemosensor is developed which can detect Al(iii) and F− ions up to nano- and picomolar (lowest detection so far) detection limit, respectively, also utilized to establish aluminum-toxicity effect in biological systems.
Mechanism of nickel-catalyzed direct carbonyl-Heck coupling reaction: the crucial role of second-sphere interactions
Authors: Bian Jian-Hong , Tong Wen-Yan , Pitsch Chloe E. , Wu Yan-Bo , Wang Xiaotai
Published: January 2021

We present a detailed DFT mechanistic study on the first Ni-catalyzed direct carbonyl-Heck coupling of aryl triflates and aldehydes to afford ketones.
Recent progress in the design and synthesis of zeolite-like metal–organic frameworks (ZMOFs)
Authors: Liu Xinyao , Liu Yunling
Published: January 2021

ZMOFs are a subset of MOFs that exhibit zeolite-like topologies. Using molecular building block strategy, many ZMOFs with high stability and excellent performance can be rationally designed and synthesized using different secondary building units.
Ruthenium complexes of phosphine–amide based ligands as efficient catalysts for transfer hydrogenation reactions
Authors: Yadav Samanta , Vijayan Paranthaman , Yadav Sunil , Gupta Rajeev
Published: January 2021

Ru(ii) complexes of phosphine–amide ligands function as efficient catalysts for the transfer hydrogenation of assorted carbonyl compounds, including a few challenging biologically relevant substrates, using isopropanol as the hydrogen source.
Recent progress in tin-based perovskite solar cells
Authors: Cao Jiupeng , Yan Feng
Published: January 2021

This work provides a comprehensive review on strategies like reducing agents, morphology control, compositional engineering and device engineering for fabricating efficient and stable tin-based perovskite solar cells.
Breakdown mechanisms of whey protein gels during dynamic in vitro gastric digestion
Authors: Mennah-Govela Yamile A. , Bornhorst Gail M.
Published: January 2021

Particle geometry influenced the breakdown mechanisms impacting the pH, pepsin activity, and protein hydrolysis of whey protein gels during dynamic in vitro gastric digestion.
Stromal cell identity modulates vascular morphogenesis in a microvasculature-on-a-chip platform
Authors: Margolis Emily A. , Cleveland David S. , Kong Yen P. , Beamish Jeffrey A. , Wang William Y. , Baker Brendon M. , Putnam Andrew J.
Published: January 2021

We employed a multiplexed microvasculature-on-a-chip platform to investigate the impact of stromal cell identity on microvascular network formation and perfusion.
Traditional Chinese medicine (TCM) as a source of new anticancer drugs
Authors: Yao Chang-liang , Zhang Jian-qing , Li Jia-yuan , Wei Wen-long , Wu Shi-fei , Guo De-an
Published: January 2021

Drugs derived from traditional Chinese medicines (TCM) include both single chemical entities and multi-component preparations.
Improving the thermoelectric performance of Cu2SnSe3via regulating micro- and electronic structures
Authors: Ming Hongwei , Zhu Chen , Qin Xiaoying , Jabar Bushra , Chen Tao , Zhang Jian , Xin Hongxing , Li Di , Zhang Jinhua
Published: January 2021

A 2.3-fold rise in power factor and 40% drop in the lattice thermal conductivity is realized through micro- and electronic structure modulation with mechanical milling, leading to a large ZT = 0.9 for Cu2SnSe3.
Quadruple-responsive nanoparticle-mediated targeted combination chemotherapy for metastatic breast cancer
Authors: Huang Yamei , Xie Dengchao , Gou Shuangquan , Canup Brandon S. B. , Zhang Guizheng , Dai Fangyin , Li Changming , Xiao Bo
Published: January 2021

Multi-responsive nanoparticles loaded with curcumin and 5-fluorouracil showed synergistic treatment effects against metastatic breast cancer.
Rh(ii)-Catalyzed denitrogenative 1-sulfonyl-1,2,3-triazole-1-alkyl-1,2,3-triazole cross-coupling as a route to 3-sulfonamido-1H-pyrroles and 1,2,3-triazol-3-ium ylides
Authors: Koronatov Alexander N. , Afanaseva Kseniia K. , Sakharov Pavel A. , Rostovskii Nikolai V. , Khlebnikov Alexander F. , Novikov Mikhail S.
Published: January 2021

The reaction of 1-alkyl-1H-1,2,3-triazoles with rhodium(ii) azavinyl carbenes, generated from 1-sulfonyl-1H-1,2,3-triazoles, was utilized to prepare 3-sulfonamido-1H-pyrroles and 1,2,3-triazol-3-ium ylides in good yields.
Recent development in transition metal-catalysed C–H olefination
Authors: Ali Wajid , Prakash Gaurav , Maiti Debabrata
Published: January 2021

Transition metal-catalysed functionalizations of inert C–H bonds to construct C–C bonds represent an ideal route in the synthesis of valuable organic molecules.
Revealing the bonding of solvated Ru complexes with valence-to-core resonant inelastic X-ray scattering
Authors: Biasin Elisa , Nascimento Daniel R. , Poulter Benjamin I. , Abraham Baxter , Kunnus Kristjan , Garcia-Esparza Angel T. , Nowak Stanislaw H. , Kroll Thomas , Schoenlein Robert W. , Alonso-Mori Roberto , Khalil Munira , Govind Niranjan , Sokaras Dimosthenis
Published: January 2021

Combined experimental and theoretical Ru 2p4d resonant inelastic X-ray scattering study probes the chemical bonding and the valence excited states of solvated Ru complexes.
Flame-retardant single-ion conducting polymer electrolytes based on anion acceptors for high-safety lithium metal batteries
Authors: Deng Kuirong , Guan Tianyu , Liang Fuhui , Zheng Xiaoqiong , Zeng Qingguang , Liu Zheng , Wang Guangxia , Qiu Zhenping , Zhang Yangfan , Xiao Min , Meng Yuezhong , Wei Lai
Published: January 2021

A flame-retardant single-ion conducting polymer electrolyte was constructed by incorporating allylboronic acid pinacol ester into the 3D network to trap the anions, leading to unity lithium-ion transference number and high ionic conductivity.
A new nitrogen fixation strategy: the direct formation of *N2− excited state on metal-free photocatalyst
Authors: Niu Xianghong , Sun Dazhong , Shi Li , Bai Xiaowan , Li Qiang , Li Xing'ao , Wang Jinlan
Published: January 2021

For photocatalytic N2 fixation, electrons at the valence-band edge of the photocatalyst can be directly excited to π* orbitals, which not only significantly activates N2, but also effectively improves the selectivity.
Biomineralized iron oxide–polydopamine hybrid nanodots for contrast-enhancedT1-weighted magnetic resonance imaging and photothermal tumor ablation
Authors: Wang Ze’ai , Wang Yanfeng , Wang Yuan , Wei Chaogang , Deng Yibin , Chen Huabing , Shen Junkang , Ke Hengte
Published: January 2021

Biomineralized iron oxide–polydopamine hybrid nanodots are constructed using albumin nanoreactors to facilitate contrast-enhancedT1-weighted magnetic resonance imaging as well as photothermal therapeutic efficacy.
Bulk autophagy induction and life extension is achieved when iron is the only limited nutrient in Saccharomyces cerevisiae
Authors: Montella-Manuel Sandra , Pujol-Carrion Nuria , Mechoud Mónica A. , de la Torre-Ruiz Maria Angeles
Published: January 2021

We have investigated the effects that iron limitation provokes in Saccharomyces cerevisiae exponential cultures. We have demonstrated that one primary response is the induction of bulk autophagy mediated by TORC1. Coherently, Atg13 became dephosphorylated whereas Atg1 appeared phosphorylated. The signal of iron deprivation requires Tor2/Ypk1 activity and the inactivation of Tor1 leading to Atg13 dephosphorylation, thus triggering the autophagy process. Iron replenishment in its turn, reduces autophagy flux through the AMPK Snf1 and the subsequent activity of the iron-responsive transcription factor, Aft1. This signalling converges in Atg13 phosphorylation mediated by Tor1. Iron limitation promotes accumulation of trehalose and the increase in stress resistance leading to a quiescent state in cells. All these effects contribute to the extension of the chronological life, in a manner totally dependent on autophagy activation.
Optimisation of virtual cooperative spectrum sensing for UAV‐based interweave cognitive radio system
Authors: Wu Jun , Chen Yang , Li Pei , Zhang Jia , Wang Cong , Tang Jifei , Xia Lanhua , Lu Conghui , Song Tiecheng
Published: January 2021

In an interweave cognitive radio system, cooperative spectrum sensing has been recognised as a key technology to enable secondary users to opportunistically access licensed spectrum band without harmful interference to primary users. At the same time, the unmanned aerial vehicle equipped with spectrum sensing and data transmission facilities is gaining more popularity in different applications. An unmanned aerial vehicle‐based interweave cognitive radio is investigated in which the unmanned aerial vehicle is used as a secondary user, but unlike the participation of multiple secondary users in traditional cooperative spectrum sensing, a virtual cooperative spectrum sensing model is introduced into the periodic spectrum sensing frame structure. Afterwards, the authors further propose an energy‐efficient virtual cooperative spectrum sensing with the sequential 0/1 fusion rule to reduce the average number of decisions without any loss in the detection performance. Sequentially, the authors formulate the optimisation of virtual cooperative spectrum sensing for unmanned aerial vehicle‐based interweave cognitive ratio system as the optimal sequential 0/1 fusion problem on the basis of the K‐out‐of‐N fusion rule and prove the formulated problem indeed has one optimal K, which yields the highest throughput. Finally, numerical simulations are presented to demonstrate the correctness of theoretical analyses and the effectiveness of the virtual cooperative spectrum sensing with the sequential 0/1 fusion rule.
A specific perspective: Subway driver behaviour recognition using CNN and time‐series diagram
Authors: Huang Shize , Yang Lingyu , Chen Wei , Tao Ting , Zhang Bingjie
Published: January 2021

Urban rail transit, especially the subway, has been booming in China for a decade, imposing safety challenges on all related parties. Drivers’ behaviours are particularly crucial. Typically, drivers’ actions are recorded by cameras, and the surveillance videos are evaluated manually. Current driver behaviour recognition methods mostly target the bus or car drivers and can hardly be implemented for subways, because subway drivers follow a rigid working code that needs a time sequence of movements to describe. In this study, we propose a recognition model to automatically recognise behaviours from single‐frame images that are extracted from surveillance videos; second, we convert the recognition results into time series diagrams, thus the recognised behaviours can be interpreted and analysed statistically and effectively. The validation experiments demonstrate that the convolutional neural network model can recognise 96.20% driver behaviours, and time series diagrams add time information to the behaviours, providing a convincible reference for subway driver evaluation.
Novel balanced single/dual‐band bandpass filters based on a circular patch resonator
Authors: Zhang Qiao , Chen Chang , Chen Weidong , Ding Jun , Zhang Hualiang
Published: January 2021

A new strategy for designing single‐band and dual‐band balanced bandpass filters (BPFs) based on a circular patch resonator is proposed in this study. By altering the output balanced ports of the balanced BPFs to inhibit or transport the TM31 mode of the circular patch resonator under the differential‐mode (DM) excitation, a single‐band or dual‐band balanced BPF can be realized. As the odd modes could be restrained under the common‐mode (CM) excitation, the balanced BPFs could feature high CM suppression in the DM passbands. Meanwhile, several perturbing tactics are introduced to improve the performance of the balanced BPFs. Specifically, perturbation vias are presented to disturb the electric field distribution to enhance the CM suppression in the DM passbands, and slots are applied on the circular patch resonators to perturb the current distribution to amend the second DM passband of the dual‐band balanced BPF. The proposed single‐band and dual‐band balanced BPFs are fabricated and characterized. Good agreement can be achieved between the simulated and measured results of the fabricated balanced BPFs, which validates the feasibility of the proposed design method.
Diffuse radio emission from galaxy clusters in the LOFAR Two-metre Sky Survey Deep Fields
Authors: Osinga E. , van Weeren R. J. , Boxelaar J. M. , Brunetti G. , Botteon A. , Brüggen M. , Shimwell T. W. , Bonafede A. , Best P. N. , Bonato M. , Cassano R. , Gastaldello F. , di Gennaro G. , Hardcastle M. J. , Mandal S. , Rossetti M. , Röttgering H. J. A. , Sabater J. , Tasse C.
Published: January 2021

Low-frequency radio observations are revealing an increasing number of diffuse synchrotron sources from galaxy clusters, primarily in the form of radio halos or radio relics. The existence of this diffuse synchrotron emission indicates the presence of relativistic particles and magnetic fields. It is still an open question as to exactly what mechanisms are responsible for the population of relativistic electrons driving this synchrotron emission. The LOFAR Two-metre Sky Survey Deep Fields offer a unique view of this problem. Reaching noise levels below 30 μJy beam−1, these are the deepest images made at the low frequency of 144 MHz. This paper presents a search for diffuse emission in galaxy clusters in the first data release of the LOFAR Deep Fields. We detect a new high-redshift radio halo with a flux density of 8.9 ± 1.0 mJy and corresponding luminosity of P144MHz = (3.6 ± 0.6) × 1025 W Hz−1 in an X-ray detected cluster at z = 0.77 with a mass estimate of M500 = 3.3−1.7+1.1 × 1014 M⊙. Deep upper limits are placed on clusters with non-detections. We compare the results to the correlation between halo luminosity and cluster mass derived for radio halos found in the literature. This study is one of a few to find diffuse emission in low mass (M500 < 5 × 1014 M⊙) systems and shows that deep low-frequency observations of galaxy clusters are fundamental for opening up a new part of parameter space in the study of non-thermal phenomena in galaxy clusters.
Influence of grain size and composition on the contraction rates of planetary envelopes and on planetary migration
Authors: Bitsch Bertram , Savvidou Sofia
Published: January 2021

A crucial phase during planetary growth is the migration, when the planetary core has been assembled but has not yet opened a deep gap. During this phase, the planet is subject to fast type-I migration, which is mostly directed inwards, and the planet can lose a significant fraction of its semi-major axis. The duration of this phase is set by the time required for the planetary envelope to contract before it reaches a mass similar to that of the planetary core, which is when runaway gas accretion can set in and the planet can open a deeper gap in the disc, transitioning into the slower type-II migration. This envelope contraction phase depends crucially on the planetary mass and on the opacity inside the planetary envelope. Here we study how different opacity prescriptions influence the envelope contraction time and how this in turn influences how far the planet migrates through the disc. We find within our simulations that the size distribution of the grains as well as the chemical composition of the grains crucially influences how far the planet migrates before reaches the runaway gas accretion phase. Grain size distributions with larger grain sizes result in less inward migration of the growing planet because of faster gas accretion enabled by more efficient cooling. In addition, we find that planets forming in water-poor environments can contract their envelope faster and therefore migrate less, implying that gas giants forming in water-poor environments might be located further away from their central star compared to gas giants forming in water-rich environments. Future studies of planet formation that aim to investigate the chemical composition of formed gas giants need to take these effects into account self-consistently.
SGR 0755−2933: a new high-mass X-ray binary with the wrong name
Authors: Doroshenko V. , Santangelo A. , Tsygankov S. S. , Ji L.
Published: January 2021

The soft gamma-ray repeater candidate SGR 0755−2933 was discovered in 2016 by Swift/BAT, which detected a short (∼30 ms), powerful burst typical of magnetars. To understand the nature of the source, we present here an analysis of follow-up observations of the tentative soft-X-ray counterpart of the source obtained with Swift/XRT, NuSTAR, and Chandra. From our analysis we conclude that, based on the observed counterpart position and properties, SGR 0755−2933 is not a soft gamma-ray repeater but rather a new high-mass X-ray binary. We suggest it be referred to as 2SXPS J075542.5−293353. We therefore conclude that the available data do not allow us to confirm existence and identify the true soft-X-ray counterpart to the burst event. The presence of a soft counterpart is nevertheless essential to unambiguously associate the burst with a magnetar flare, and we conclude that the magnetar origin of the burst and a precise burst location remain uncertain and require further investigation.
The past and future obliquity of Saturn as Titan migrates
Authors: Saillenfest Melaine , Lari Giacomo , Boué Gwenaël , Courtot Ariane
Published: January 2021

Context. Giant planets are expected to form with near-zero obliquities. It has recently been shown that the fast migration of Titan could be responsible for the current 26.7°-tilt of Saturn’s spin axis.

Aims. We aim to quantify the level of generality of this result by measuring the range of parameters allowing for this scenario to happen. Since Titan continues to migrate today, we also aim to determine the obliquity that Saturn will reach in the future.

Methods. For a large variety of migration rates for Titan, we numerically propagated the orientation of Saturn’s spin axis both backwards and forwards in time. We explored a broad range of initial conditions after the late planetary migration, including both small and large obliquity values.

Results. In the adiabatic regime, the likelihood of reproducing Saturn’s current spin-axis orientation is maximised for primordial obliquities between about 2° and 7°. For a slightly faster migration than expected from radio-science experiments, non-adiabatic effects even allow for exactly null primordial obliquities. Starting from such small tilts, Saturn’s spin axis can evolve up to its current state provided that: (i) the semi-major axis of Titan changed by more than 5% of its current value since the late planetary migration, and (ii) its migration rate does not exceed ten times the nominal measured rate. In comparison, observational data suggest that the increase in Titan’s semi-major axis exceeded 50% over 4 Gyr, and error bars imply that the current migration rate is unlikely to be larger than 1.5 times its nominal value.

Conclusions. If Titan did migrate substantially before today, tilting Saturn from a small obliquity is not only possible, but it is the most likely scenario. Saturn’s obliquity is still expected to be increasing today and could exceed 65° in the future. Maximising the likelihood would also put strict constraints on Saturn’s polar moment of inertia. However, the possibility remains that Saturn’s primordial obliquity was already large, for instance as a result of a massive collision. The unambiguous distinction between these two scenarios would be given by a precise measure of Saturn’s polar moment of inertia.
High performance terahertz quantum cascade lasers
Authors: Li Y.Y. , Liu J. Q. , Liu F.Q. , Wang Z. G.
Published: January 2021

Terahertz region is the electromagnetic gap between the infrared optoelectronics and the high frequency electronics, which is of broad prospects in applications. The application requirements drive the rapid development in Terahertz technologies including sources, detectors and systems. In the last two decades, quantum cascade laser has made great progress as one of the most promising terahertz sources. In this paper, we present the development of terahertz quantum cascade lasers in our group.
Lumbale Rückenschmerzen und Wirbelsäulenverletzungen bei Sportlern – Ursachen und Risikomanagement
Authors: Sheeran Liba
Published: January 2021

Sportler leiden häufig unter lumbalen Rückenschmerzen. Die Ursachen dafür bleiben oft unklar und auch der Umgang mit den Beschwerden ist nicht einfach – erst recht nicht, wenn aufgrund der Schmerzen die sportliche Laufbahn auf der Kippe steht. Da ist guter Rat teuer.
Biomechanische Grundlagen des Werfens
Authors: Heger Hendrik , Wank Veit
Published: January 2021

Wahrscheinlich braucht niemandem erklärt zu werden, was man mit einem Schneeball machen soll: Das Werfen gehört zu den grundlegenden menschlichen Bewegungsformen und ist in vielen Sportarten unverzichtbar. Intensität und Umfang der Würfe sowie mögliche fehlerhafte Bewegungsausführungen können allerdings akut wie langfristig zu Verletzungen führen, denen in einem ersten Schritt bereits durch ein grundlegendes Verständnis der Bewegungsmechanik vorgebeugt werden kann.
Quantification of Early and Intermediate Age-related
Macular Degeneration Using OCT “en face” Presentation
Authors: Jürgens Frauke , Rothaus Kai , Faatz Henrik , Heimes-Bussmann Britta , Pauleikhoff Daniel , Lommatzsch Albrecht Peter
Published: January 2021

Background Early and intermediate age-related macular degeneration (AMD)
results in drusen deposits under the retinal pigment epithelium (RPE). These
early stages of AMD exhibit different risks of progressing to late AMD. To date,
early AMD has been classified and quantified by fundus photography. This does
not appear to be sensitive enough for clinical trials studying the impact on
drusen. SD-OCT with two-dimensional rendering of the segmented slices analysed
allows for en face imaging of the drusen. The present trial studied the
potential of quantifying early and intermediate AMD by en-face optical coherence
tomography (OCT).

Material and Methods Thirty-one eyes of 29 patients in different stages of
early and intermediate AMD were studied. To this end, fundus photographs (Kowa
VX-10i, Kowa, Tokyo, Japan) and en-face OCT images (RTVue XR Avanti, Optovue,
Inc., Fremont, CA, USA) were taken. First, different segmentation levels (6 µm
underneath the RPE, on the RPE, 6 µm and 9 µm above the RPE) and different layer
thicknesses (5 µm, 10 µm, 20 µm and 30 µm) were analysed to determine the best
segmentation for visualising drusen. Drusen were marked manually and their
number and surface area calculated. This analysis was then compared with the
standardised drusen analyses on fundus photography. Additional changes in early
and intermediate AMD such as pigment epithelial detachments (PEDs) and
subretinal drusenoid deposits (SDD) as well as small atrophies were also
documented and compared.

Outcomes The best segmentation for delineating the drusen on the en-face
OCT images was found to be a segmentation 6 µm underneath the RPE with a slice
thickness of 20 µm. Comparison of drusen quantification on en-face OCT images
with the standardised drusen analysis on fundus photography revealed
particularly good similarity. Other changes in early and intermediate AMD, such
as PEDs, SDD and small atrophies, were easier to assess on the en-face OCT
images.

Conclusions The analysis and quantification of drusen from en-face OCT
images with 20 µm segmentation at 6 µm underneath the RPE allows differentiated
quantification of various drusen characteristics. Moreover, other changes in
early and intermediate AMD can also be analysed. In future observational and
clinical trials, this could help quantify drusen.
Lebensqualität nach Brustkrebs: Erfassung, Relevanz und effektive Interventionen
Authors: Schmidt Martina , Steindorf Karen
Published: January 2021

Gesundheitsbezogene Lebensqualität ist für Brustkrebsbetroffene in allen Stadien, sowohl während als auch mittel- und langfristig nach Abschluss der Therapie, von großer Relevanz. Bei Zulassungsstudien für neue Behandlungen sowie wissenschaftlichen Studien zum Vergleich verschiedener Therapien gewinnt Lebensqualität als Endpunkt zunehmend an Bedeutung. Neben einer kurzen globalen Einschätzung der Lebensqualität sollten weitere wichtige Patient-Reported Outcomes erhoben werden. Patientinnen mit Brustkrebs berichten häufig über Einschränkungen durch Fatigue, Schlafprobleme, sexuelle bzw. klimakterische Probleme, kognitive Probleme, psychische Probleme und Verlust an körperlicher Leistungsfähigkeit. Die Lebensqualität nach Brustkrebs könnte vermutlich weiter gesteigert werden, wenn Aufklärung, Screening und Behandlung dieser Symptome systematischer Bestandteil der onkologischen Versorgung würden.
Rationaler Einsatz der klassischen Naturheilverfahren und Balneotherapie in der rheumatologischen Rehabilitation
Authors: Lohmann Sandra , Schwarz-Eywill Michael , Mahn Karin , Gerß Lisa , Gehlen Martin
Published: January 2021

Zu den klassischen Naturheilverfahren gehören unter anderen die Elemente Hydrotherapie, Bewegungstherapie, Ernährungstherapie, Ordnungstherapie und Phytotherapie. Die Ordnungstherapie ist das übergreifende Therapieelement. Zahlreiche naturheilkundliche Verfahren sind ebenso Bestandteil balneologischer Therapiekonzepte. In jeder modernen rheumatologischen Rehabilitation werden die naturheilkundlichen Elemente therapeutisch eingesetzt mit dem Ziel, Funktionseinschränkungen und die daraus entstehenden Folgen auf Aktivitäten des Alltags und auf den Beruf zu verbessern. Der Artikel soll einen Überblick über evidenzbasierte naturheilkundliche Therapien und ihren Einsatz in der rheumatologischen Rehabilitation zu geben.
Beeinflussung von strukturellen Dysphagien durch eine phoniatrische Rehabilitation
Authors: Keilmann Annerose , Wach Franziska-Sophie , Konerding Uwe
Published: January 2021

Patienten, die wegen Kopf-Hals-Tumoren behandelt wurden, leiden häufig an Dysphagien. Dysphagien können mittels Fragebögen, die die Betroffenen ausfüllen, oder über Expertenratings, die z. B. die Konsistenz der Nahrung, die Dauer der Nahrungsaufnahme, die Notwendigkeit einer perkutanen endoskopischen Gastrostomie (PEG) und die Ergebnisse instrumenteller Untersuchungen wie der fiberoptischen endoskopischen Evaluation des Schluckens (FEES) berücksichtigen, bewertet werden. Das Ziel unserer Studie war die Untersuchung des Effekts einer phoniatrischen stationären Rehabilitation bei Patienten, die wegen eines Kopf-Hals-Tumors behandelt worden waren. Zu Beginn und am Ende der Reha füllten die 219 Teilnehmer (davon 138 Männer) im mittleren Alter von 62,8 (± 10,2) Jahren die deutsche Version des Eating Assessment Tools (EAT-10) aus und sie wurden anhand des Bogenhausener Dysphagie-Scores (BODS) unter Berücksichtigung von anamnestischen und klinischen Daten klassifiziert.

In beiden Parametern ergaben sich signifikante Verbesserungen, aber beide Parameter waren nur mäßig korreliert. Die Veränderungen in beiden Parametern waren nicht korreliert.

Zur Untersuchung von Dysphagien sollten sowohl klinische Einschätzungen als auch die subjektive Beurteilung erfasst werden
Mild Copper-Catalyzed Addition of Arylboronic Esters to Di-tert-butyl Dicarbonate: An Easy Access to Methyl Arylcarboxylates
Authors: Liu Jing-Hui , Hu Guo-Qin , Xu Jin-Di , Su Xiao-Bo , Wang Cai , Yao Li-Wei
Published: January 2021

An efficient copper-catalyzed addition of arylboronic esters to (Boc)2O was developed. The reaction can be conducted under exceedingly mild conditions and is compatible with a variety of synthetically relevant functional groups. It therefore represents a useful alternative route for the synthesis of methyl arylcarboxylates. A preliminary mechanistic study indicated the involvement of an addition–elimination mechanism.
Pre-eclampsia: Universal Screening or Universal Prevention for Low and Middle-Income Settings?
Authors: De Oliveira Leandro Gustavo , Diniz Angélica Lemos Debs , Prado Caio Antônio de Campos , Cunha Filho Edson Vieira Da , Souza Francisco Lázaro Pereira De , Korkes Henri Augusto , Ramos José Geraldo , Costa Maria Laura , Corrêa Junior Mário Dias , Sass Nelson , Cavalli Ricardo De Carvalho , Martins-Costa Sérgio Hofmeister De Almeida , Peraçoli José Carlos
Published: January 2021

Pre-eclampsia (PE) is a severe disorder that affects up to 8% of all pregnancies and represents an important cause of maternal and perinatal morbidity and mortality. The screening of the disease is a subject of studies, but the complexity and uncertainties regarding its etiology make this objective a difficult task. In addition, the costs related to screening protocols, the heterogeneity of the most affected populations and the lack of highly effective prevention methods reduce the potential of current available algorithms for screening. Thus, the National Specialized Commission of Hypertension in Pregnancy of the Brazilian Association of Gynecology and Obstetrics Federation (Febrasgo, in the Portuguese acronym) (NSC Hypertension in Pregnancy of the Febrasgo) considers that there are no screening algorithms to be implemented in the country to date and advocates that Aspirin and calcium should be widely used.
Metrics Used to Quantify Fecal Incontinence and Constipation
Authors: Hunt Cameron W. , Cavallaro Paul M. , Bordeianou Liliana G.
Published: January 2021

While fecal incontinence and constipation can be measured through physiological testing, the subjective experience of severity and impact on health-related quality of life lead to both being most effectively captured through patient-reported measures. Patient-reported measures of severity and impact help to determine baseline symptoms, guide clinical decision making, and compare various treatments. Here, we take pause to review the psychometric qualities that make effective instruments, and discuss some of the most commonly used instruments along with the reasons behind their use. In addition, we highlight the benefits of a standardized instrument designed to evaluate the major symptoms of patients presenting with pelvic floor disorders (including fecal incontinence and constipation). Ultimately, we aim to provide guidance in choosing appropriate instruments for clinical and research use.
Follicular Fluid from Infertile Women with Mild Endometriosis Impairs In Vitro Bovine Embryo Development: Potential Role of Oxidative Stress
Authors: Giorgi Vanessa Silvestre Innocenti , Ferriani Rui Alberto , Navarro Paula Andrea
Published: January 2021

Objective To investigate whether follicular fluid (FF) from infertile women with mild endometriosis (ME) alters in vitro bovine embryo development, and whether the antioxidants N-acetyl-cysteine (NAC) and/or L-carnitine (LC) could prevent such damages.

Methods Follicular fluid was obtained from infertile women (11 with ME and 11 control). Bovine oocytes were matured in vitro divided in: No-FF, with 1% of FF from control women (CFF) or ME women (MEFF); with 1.5 mM NAC (CFF + NAC, MEFF + NAC), with 0.6 mg/mL LC (CFF + LC, MEFF + LC), or both antioxidants (CFF + NAC + LC, MEFF + NAC + LC). After in vitro fertilization, in vitro embryo culture was performed for 9 days.

Results A total of 883 presumptive zygotes were cultured in vitro. No differences were observed in cleavage rate (p = 0.5376) and blastocyst formation rate (p = 0.4249). However, the MEFF group (12.5%) had lower hatching rate than the No-FF (42.1%, p = 0.029) and CFF (42.9%, p = 0.036) groups. Addition of antioxidants in the group with CFF did not alter hatching rate (p ≥ 0.56), and in groups with MEFF, just NAC increased the hatching rate [(MEFF: 12.5% versus MEFF + NAC: 44.4% (p = 0.02); vs MEFF + LC: 18.8% (p = 0.79); versus MEFF + NAC + LC: 30.8% (p = 0.22)].

Conclusion Therefore, FF from infertile women with ME added to medium of in vitro maturation of bovine oocytes impairs hatching rate, and NAC prevented these damages, suggesting involvement of oxidative stress in worst of oocyte and embryo quality of women with ME.
Residual Disease after Operative Hysteroscopy in Patients with Endometrioid Endometrial Cancer Associated with Polyps
Authors: Simonsen Marcelo , Mantoan Henrique , Faloppa Carlos Chaves , Kumagai Lillian Yuri , Badiglian Filho Levon , Machado Andrea Guerreiro , Tayfour Najla Mohamed , Baiocchi Glauco
Published: January 2021

Objective To evaluate the presence of residual disease in the uterine specimen after hysteroscopic polypectomy or polyp biopsy in patients with endometrioid endometrial cancer (EC).

Methods We analyzed a series of 104 patients (92 cases from the Hospital AC Camargo and 12 from the Hospital do Servidor Público Estadual de São Paulo) with polyps that were diagnosed by hysteroscopy, showing endometrioid EC associated with the polyp or in the final pathological specimen. Patients underwent a surgical approach for endometrial cancer from January 2002 to January 2017. Their clinical and pathological data were retrospectively retrieved from the medical records.

Results In 78 cases (75%), the polyp had EC, and in 40 (38.5%), it was restricted to the polyp, without endometrial involvement. The pathologic stage was IA in 96 cases (92.3%) and 90 (86.5%) had histologic grade 1 or 2. In 18 cases (17.3%), there was no residual disease in the final uterine specimen, but only in 9 of them the hysteroscopy suggested that the tumor was restricted to the polyp. In 5 cases (4.8%) from the group without disease outside of the polyp during hysteroscopy, myometrial invasion was noted in the final uterine specimen. This finding suggests the possibility of disease extrapolation through the base of the polyp.

Conclusion Patients with endometrioid EC associated with polyps may have the tumor completely removed during hysteroscopy, but the variables shown in the present study could not safely predict which patient would have no residual disease.
Agreement Analysis between Sonographic Estimates and Birth Weight, by the WHO and Intergrowth-21st Tables, in Newborns of Diabetic Mothers
Authors: Souza Marcus Vinícius Rodrigues de , Fróes Lívia Pinto e , Cortez Pedro Afonso , Lauria Márcio Weissheimer , Aguiar Regina Amélia Lopes de , Rajão Kamilla Maria Araújo Brandão
Published: January 2021

Objective To analyze the agreement, in relation to the 90th percentile, of ultrasound measurements of abdominal circumference (AC) and estimated fetal weight (EFW), between the World Health Organization (WHO) and the International Fetal and Newborn Growth Consortium for the 21st Century (intergrowth-21st) tables, as well as regarding birth weight in fetuses/newborns of diabetic mothers.

Methods Retrospective study with data from medical records of 171 diabetic pregnant women, single pregnancies, followed between January 2017 and June 2018. Abdominal circumference and EFW data at admission (from 22 weeks) and predelivery (up to 3 weeks) were analyzed. These measures were classified in relation to the 90th percentile. The Kappa coefficient was used to analyze the agreement of these ultrasound variables between the WHO and intergrowth-21st tables, as well as, by reference table, these measurements and birth weight.

Results The WHO study reported 21.6% large-for-gestational-age (LGA) newborns while the intergrowth-21st reported 32.2%. Both tables had strong concordances in the assessment of initial AC, final AC, and initial EFW (Kappa = 0.66, 0.72 and 0.63, respectively) and almost perfect concordance in relation to final EFW (Kappa = 0.91). Regarding birth weight, the best concordances were found for initial AC (WHO: Kappa = 0.35; intergrowth-21st: Kappa = 0.42) and with the final EFW (WHO: Kappa = 0.33; intergrowth- 21st: Kappa = 0.35).

Conclusion The initial AC and final EFW were the parameters of best agreement regarding birth weight classification. The WHO and intergrowth-21st tables showed high agreement in the classification of ultrasound measurements in relation to the 90th percentile. Studies are needed to confirm whether any of these tables are superior in predicting short- and long-term negative outcomes in the LGA group.
Prevalence of Depression and Anxiety during the COVID-19 Pandemic among the Residents of an Urban Slum in North India
Authors: Rehman Tanveer , Singh Tarundeep , Sharma Sugandhi , Kumar Jitender , Govindan Dhanajayan , Singh Shubh Mohan
Published: January 2021

Objectives This study aimed to estimate the prevalence of depression and anxiety, and assess the knowledge, practice, and concerns regarding coronavirus disease 2019 (COVID-19) among the residents of an urban slum in Chandigarh, India.

Materials and Methods Participants were screened using Patient Health Questionnaire-9 and Generalized Anxiety Disorder-7 scales.

Results The mean (standard deviation) age of 200 enrolled participants was 33 (13) years with 83% (n = 166) being females. The prevalence of depression and anxiety was 3.5% (95% confidence interval [CI]: 0.95–6.05) and 2.5% (95% CI: 0.34–4.66), respectively. Of total, 46% (n = 92) knew that COVID-19 can transmit through droplets and 30.5% (n = 61) were concerned that they might get infected with disease. Half of the participants (n = 100) believed that there was unnecessary worry regarding COVID-19 and 78% (n = 156) covered mouth while coughing or sneezing.

Conclusion To cope with this critical situation, it is necessary to strengthen the awareness programs targeting the mental health issues of the people.
Variceal Veins Embolization and Left Renal Vein Stenting in a Patient with Combined Nutcracker and May–Thurner Syndrome
Authors: Aghdasi Sina , Serati Ali Reza , Moosavi Jamal , Emami Sepideh , Movahed Mohammad Reza
Published: January 2021

Nutcracker syndrome is defined as a compression of left renal vein leading to symptomatic hematuria and flank pain. There are very few reports about its association with May–Thurner syndrome that is related to compression of left iliac vein causing severe leg edema. We are reporting a rare case of a patient having both conditions successfully treated with sequential percutaneous interventions. This case and treatment options are discussed in detail.
Effect of Different Host-Related Factors on Postoperative Endodontic Pain in Necrotic Teeth Dressed with Interappointment Intracanal Medicaments: A Multicomparison Study
Authors: Shabbir Juzer , Khurshid Zohaib , Qazi Fazal , Sarwar Huma , Afaq Hasan , Salman Saima , Adanir Necdet
Published: January 2021

Objectives The current study aimed to assess the impact of factors such as age, gender, and the tooth type on postoperative endodontic pain in necrotic teeth with symptomatic periapical periodontitis and radiolucency dressed randomly with either calcium hydroxide or propolis paste.

Materials and Methods The standard chemomechanical root canal preparation of 80 teeth was performed by the primary investigator. The intracanal medicaments were inserted by the secondary operator. Patients self-recorded their postoperative endodontic pain intensity with the help of visual analog scale at 4, 12, 24 (day 2), 48 (day 3), and 72 (day 4) hours. During analysis, patients (68/80) were grouped according to gender, age, and the tooth type.

Statistical Analysis Mann–Whitney’s U test was applied for mean pain score comparison between genders and between tooth type. Kruskal–Wallis’ test was applied for mean pain score comparison between the age groups.

Results No significant difference (p > 0.05) in pain scores was found between the age groups and between the tooth types. Males had significantly higher pain scores as compared with females at days 2 (p = 0.035), 3 (p = 0.023), and 4 (p = 0.020).

Conclusion The results suggested that there was no impact of age and tooth types on postoperative endodontic pain.
Preventing Type 2 Diabetes in Women with Previous Gestational Diabetes: Reviewing the Implementation Gaps for Health Behavior Change Programs
Authors: Lim Siew , Chen Mingling , Makama Maureen , O'Reilly Sharleen
Published: January 2021

Gestational diabetes mellitus (GDM) places a woman at high risk of developing subsequent type 2 diabetes mellitus (T2DM), particularly in the first 5 years postpartum. Engaging women in health behavior change during this period is challenging and current diabetes prevention programs were developed for middle-aged adults, all of which have limited the evidence on successful implementation for this high-risk population. In this review, we will first summarize the effects of existing diabetes prevention programs in women with a history of GDM. Second, we suggest that the programs need to be modified according to the facilitators and barriers faced by this population. Third, we propose that improving program penetration, fidelity, and participation is critical for population-level success. Finally, we outline the research priorities to improve the implementation of diabetes prevention programs for postpartum women with a history of GDM.