bluuebunny/crossref_metadata_2025 huggingface dataset:
Research on Fresh Products for Fresh E-commerce
Authors: Dai Qun , Yang Can , Zhang Shujing , Zhang Wanrong
Published: July 2020

At present, opportunities and challenges coexist in the development of e-commerce industry, which develops rapidly, but there are also many problems. Among them, the offline cold chain logistics that puzzles fresh e-commerce has not been a good solution, the key reason is that there are too many uncontrollable factors of logistics distribution, storage and fresh, and lack of high quality cold storage to meet the needs of e-commerce. This paper analyzes a series of problems of cold storage from the aspects of temperature, space location, packaging design and distribution. Finally, we can solve these problems through temperature control technology, bar code technology and advanced cold chain technology.
Research on the Project of Canteen Fat Reduction Window
Authors: Yin Wenxiao , Zhao Xiaojie , Zhang Lijun , Chen Ruixuan , Chen Yahui , Lu Yang
Published: July 2020

The physical health of students in our country is decreasing year by year, and the decline of college students is particularly prominent. Based on the student’s perspective, the campus canteen is taken as the research object, and a canteen window dedicated to the college students’ diet needs is opened for the college students. It can not only define the daily calorie intake to achieve the purpose of weight loss or control, but also consider the nutritional requirements. Aiming at the current status of the development of Internet catering, this article combines the traditional campus canteen with weight loss and the Internet to establish a canteen takeaway, combining our traditional takeaway concept with the canteen to create a unique takeout system on campus.
Process Analysis of Warehouse Logistics Information System
Authors: Wang Xinyuan , Li Mengfei , Zhang Xue , Zhang Yue
Published: July 2020

This article takes a typical warehouse logistics company as the research background. Combined with the situation of this enterprise, it describes the requirements analysis of the warehouse logistics managements system in detail and analyzes the business and data processes of the warehouse logistics information system in detail. The operation of the system enables the comprehensive network, information and automation of the warehouse logistics management process and it achieves the purpose of improving work efficiency and quality and it achieves the goal of providing better services to customers. It has certain practical significance for the construction of warehouse logistics management information system of logistics enterprises.
Research on the Transformation of Safety decision Driven by Major Accidents Based on Big Data Mining
Authors: Dai Wentian , Zhuang Yue , Zhang Supei
Published: July 2020

In recent years, major accidents have occurred in China, causing extremely heavy loss of personnel and property. Unsafe human behavior is the direct cause of accidents, while corporate security behavior has a deeper impact. This paper first reviews the research status of major security incidents and corporate security behaviors, and expounds the research gap between current social security behaviors and major security incidents. By describing the governance framework and driving force of corporate security behaviors, we can explore the content and path of social security decision driven by major security events. Based on this theoretical basis, the 8.12 Tianjin Binhai New Area explosion accident was cited. Through the network reptiles, the policy and industry trends of the China Chemical Safety Association were studied, and the NLPIRParser text search and mining method was adopted. The results show that the regulations before and after the accident have undergone major changes. As the regulations become more stringent, the company’s safety has also been steadily strengthened.
Internet of Things: Examination of efficiency and safety
Authors: Alyshev Y V , Maslov O N , Shatalov I S
Published: July 2020

The paper studies the problem of complex safety in personal area network and local area network in the Internet of Things project’s boundaries. The electromagnetic safety analysis of various wireless picocell technologies have realized by statistical simulation with applying the criterion of functional of expected utility. The results of the statistical model are presented. The model’s stochastic variables are «projected economical effect» and «environmental and ergonomic risk»; the determinate variable is internet of things realization cost. Recommendations for the selection of personal area network and local area network elements based on the Bluetooth protocol are given. The model of equivalent radiator for estimation of Internet of Things objects safety is offered. It is shown that the forced switching of all Internet of Things elements to radiation mode is an «energy threat» for sensors in the room.
The use of electronic semantization of the cognitive activity manifestations with the aim of detection of intentions of the group of people leading to the destabilization of the digital super system
Authors: Loginov E L , Grigoriev V V , Balandin V S , Boyko P A , Shkuta A A
Published: July 2020

The article deals with the possibilities of monitoring of information communities and their members’ cognitive activity in order to analyze and forecast the actions of these individuals with the use of the method of automated structuring of their real political interests and of detection of inner- and inter-class connections in a digital super system. Analysis is a relevant method to detect tendencies of the political positioning of groups of people that are forming digital information assets as well as of the management of the organizational risks that emerge.
The methodology for calculating the interval of the shortwave radio link frequency correlation with the sphericity and small-scale inhomogeneities of the ionosphere
Authors: Pashintsev V P , Gakhova N N , Skorik A D , Alekseev D V , Senokosov M A
Published: July 2020

The paper suggests the methodology for calculating the interval of the fading frequency correlation in the shortwave radio link with one discrete beam and its diffuse scattering. This methodology takes into account the effect of the sphericity and small-scale inhomogeneities of the ionosphere reflecting layer.
Modification of entropy-based algorithm for determining words boundaries in noisy conditions
Authors: Karpov A S , Drozdova V I , Shagrova G V , Romanenko M G
Published: July 2020

A modification of the algorithm for finding word boundaries in continuous speech based on an analysis of the entropy of a speech signal is described. At the preprocessing stage, the signal is divided into frames; the entropy value is calculated for each frame and compared with the threshold value of the entropy γ. The algorithm is carried out in two stages, first a rough and then more precise definition of the word boundaries is made. At each stage, its own minimum distance between words is used. A modification is proposed, which consists in the fact that the entropy threshold γ is determined on the basis of the calculated SNR coefficient taking into account the experimental selection of signal parameters at the stage of precise determination of word boundaries in a noisy speech signal. Checking the functionality of the modified algorithm on noisy signals has shown that taking into account the effect of SNR on the selection of signal parameters increases the accuracy of word boundary determination.
Simulation of the stress-strain state of shells under internal pressure using the mixed finite element method, taking into account physical nonlinearity
Authors: Arkov D P , Kochetkova O V , Gureeva N A , Matveyev A S , Shiryaeva E V
Published: July 2020

In this article, the finite element method (FEM) is used to model the stress-strain state (SSS) of shells experiencing internal pressure with elastic-plastic state being taken into account. Main geometric equations determining the location of an arbitrary point at load step are given. Mixed functionality used in implementation of FEM which allows to determine stresses and displacements simultaneously is obtained based on equality of possible and actual work of external and internal forces. Examples of stress-strain state of rotation shells with spherical and elliptical bottoms under internal pressure are provided. Static check of resultant external forces arising from applied pressure and resultant internal forces arising from stresses equality to zero is performed. Achieved results show correctness of the developed algorithm with elastic-plastic properties of the material being taken into account, ensuring that main requirements for the mathematical model are secured, namely adequacy, versatility and cost-effectiveness. Costs of resources computing are reduced by adopting a number of hypotheses and determination of stresses and strains at once ensuring cost-effectiveness and simplicity. Using developed scheme of the mixed functionality application in implementation of FEM the mathematical model acquires one of its main properties - “Potentiality”.
Effect of Sn interlayer on mechanical properties and microstructure in Al/Mg friction stir lap welding with different rotational speeds
Authors: Zheng Bo , Zhao Li , Lv Qingquan , Wan Ge , Cai Da , Dong Shijie , Hu Xinbin
Published: July 2020

The effect of Sn foil layers on the mechanical properties and microstructure of friction stir lap welded 5052 aluminium alloy and AZ31B magnesium alloy was explored in this study. Models of numerous joints were set by different rotational (700, 900, 1100, 1300 and 1500 rpm) and welding speeds (50 mm min−1). Mg/Al dissimilar lap joints with and without Sn interlayer were produced by friction stir lap welding. The results suggest that Mg2Sn intermetallic compounds formed instead of Mg17Al12 and Mg2Al3 intermetallic compounds. In direct welding, the joint are only connected by metallurgical bonding between atoms (Mg/Al). In solder joints with Sn interlayer, the joint is connected by the combined effect of metallurgical bonding between atoms (Mg/Sn, Al/Sn) and interface mechanical coupling. For the joint with Sn interlayer, the maximum fracture load of the joint with the Sn interlayer reached 3.72 kN at a rotational speed of 900 rpm. As the rotational speed is increased from 1300 rpm to 1500 rpm, the Sn content on the the advancing side and the retreating side is more, resulting in more Mg2Sn crystal content, increased crack content. The joint performance gradually decreases. For the joint without a Sn interlayer, the microscopic morphology was a river-like pattern, which was characterized by brittle fracture. For a joint with a Sn interlayer, the microscopic morphology contained micro-dimples and a small quantity of inclusions, which were characterized by mixed fracture.
Artificial neural network approach for the prediction of wear for Al6061 with reinforcements
Authors: Baig Rahmath Ulla , Javed Syed , Kazi Azharuddin , Quyam Mohammed
Published: July 2020

In the prospect of finding a lightweight and wear-resistant materials, researchers have considered aluminium-based metal matrix composites (MMC), as aluminium has a wide variety of applications but possesses low wear resistance properties. To enhance the wear resistance of aluminium alloys, ceramic particles are reinforced. In this endeavour, commercially available aluminium alloy is reinforced with 2, 4 and 6 wt% of silicon carbide (SiC) and Vanadium pentoxide (V2O5) powder to improve its wear resistance. The intensity of reinforcement in the matrix was uniform, and the Scanning Electron Microscope image showed the grain refinement and grain boundary of the MMC’s. Wear tests were performed for L16 array set, uncertainty analysis of wear measurement is evaluated, and data were used to develop Artificial Neural Network (ANN) model. The efficient ANN model with a regression coefficient of 0.999 was used to make predictions for remaining sets. Experimental and predicted wear results were analysed; it is observed that higher wt% reinforcement of V2O5 increased wear resistance of aluminium compared to SiC. The methodology adapted using ANN for prediction of wear using meagre experimentation, will lay a path for tribologists to predict the wear of novel metal matrix composites in their endeavour of finding wear-resistant materials.
On conformal field theories based on Takiff superalgebras
Authors: Quella Thomas
Published: July 2020

We revisit the construction of conformal field theories based on Takiff algebras and superalgebras that was introduced by Babichenko and Ridout. Takiff superalgebras can be thought of as truncated current superalgebras with

Z

-grading which arise from taking p copies of a Lie superalgebra

g

and placing them in the degrees

s
=
0
,
…
,

p
−
1

. Using suitably defined non-degenerate invariant forms we show that Takiff superalgebras give rise to families of conformal field theories with central charge

c
=
p
sdim
g

. The resulting conformal field theories are defined in the standard way, i.e. they lend themselves to a Lagrangian description in terms of a WZW model and their chiral energy momentum tensor is the one obtained naturally from the usual Sugawara construction. In view of their intricate representation theory they provide interesting examples of conformal field theories.
Scottish dentistry and broken promises: Woollard on presuppositions and substantial negative facts
Authors: Sneddon Andrew
Published: July 2020

Fiona Woollard claims that negative facts are parts of sequences leading to upshots when they are contrary to the presuppositions of the local community. There are three problems with Woollard’s use of presuppositions. The first is that it fails to capture an important part of our everyday understanding of doing and allowing. The second is that negative facts can be suitable to be parts of sequences even when they accord with presuppositions. The third is that even when negative facts are contrary to presuppositions, this need not be what makes them suitable to be parts of sequences of facts.
Prediction of the early response to spironolactone in resistant hypertension by the combination of matrix metalloproteinase-9 activity and arterial stiffness parameters
Authors: Rodríguez-Sánchez Elena , Navarro-García José Alberto , Aceves-Ripoll Jennifer , González-Lafuente Laura , Baldan-Martin Montserrat , de la Cuesta Fernando , Alvarez-Llamas Gloria , Barderas María G , Segura Julián , Ruilope Luis M , Ruiz-Hurtado Gema
Published: July 2020

Aims

The aim of this study was to determine whether arterial stiffness assessed with the biochemical parameter active matrix metalloproteinase (MMP)-9 and the clinical parameters pulse pressure (PP) and pulse wave velocity predicts the response to spironolactone in resistant hypertension (RH).

Methods and results

Ambulatory blood pressure (BP) and active MMP-9 (measured by zymography and ELISA) were measured at baseline, and patients were classified as having pseudo-RH or RH. Patients with RH received spironolactone and the response was determined after 8 weeks by ambulatory BP monitoring: those who achieved BP goals were considered controlled (CRH) and those who did not were considered uncontrolled (UCRH). Plasma active MMP-9 was significantly higher in patients with RH than with pseudo-RH, and correlated with 24 h systolic BP and PP. Receiver operating characteristic analysis indicated that active MMP-9 could predict the response to spironolactone, and its combination with 24 h PP and pulse wave velocity significantly improved this prediction. Moreover, plasma of patients with UCRH induced the MMP-9 expression pathway.

Conclusion

We propose active MMP-9 as a useful biomarker to identify patients with RH who will not respond to spironolactone. Combining MMP-9 activity with classical arterial stiffness parameters improves the prediction of the clinical response to spironolactone and might contribute to guide the most appropriate therapeutic decisions for patients with RH.
Knowledge gaps, lack of confidence, and system barriers to guideline implementation among European physicians managing patients with CIED lead or infection complications: a European Heart Rhythm Association/European Society of Cardiology educational needs assessment survey
Authors: Rao Archana , Garner Daniel , Starck Christoph , Kirkfeldt Rikke Esberg , Dagres Nikolaos , Didier Klug , Montano Nicolas , Heidbuchel Hein
Published: July 2020

As the number of patients with cardiac implantable electronic devices (CIEDs) grows, they are likely to present with issues to diverse groups of physicians. Guideline-adherent management is associated with improved prognosis in patients with CIED infection or lead problems but is insufficiently implemented in practice. The European Heart Rhythm Association (EHRA) with the support of the European Society of Cardiology (ESC) Working Group on Cardiovascular Surgery, performed a multinational educational needs assessment study in ESC member countries, directed at physicians who might be confronted with CIED patients with complications. A total of 336 physicians from 43 countries, reached through the ESC mailing list, participated. They included a mix of electrophysiologists, cardiologists general physicians and cardiac surgeons .One hundred and twenty-nine (38%) of the respondents performed lead extraction. The survey included eight clinical cases and a self-evaluation question of knowledge and skills to apply that knowledge. The survey looked at 14 areas of care across five stages of the patient journey. Of the non-extracting physicians over 50% felt they lacked the knowledge and skills to make the diagnosis and refer for lead extraction and over 75% felt they lacked knowledge and skills to manage aspects of extraction and post-extraction care. Barriers to correct referral were logistic and attitudinal. Extracting physicians reported significantly higher rates of adequate skills and knowledge across all five stages of the patient journey (P < 0.05). We identified major gaps in physicians’ knowledge and skills across all stages of CIED care. These gaps should be addressed by targeted educational activities and streamlining referral pathways.
Safety of smartwatches and their chargers in patients with cardiac implantable electronic devices
Authors: Tzeis Stylianos , Asvestas Dimitrios , Moraitis Nektarios , Vardas Emmanuel P , Mililis Panagiotis , Letsas Konstantinos , Kouvelas Konstantinos , Nikita Konstantina S , Vardas Panos
Published: July 2020

Aims

Cardiac implantable electronic devices (CIEDs) are susceptible to electromagnetic interference (EMI). Smartwatches and their chargers could be a possible source of EMI. We sought to assess whether the latest generation smartwatches and their chargers interfere with proper CIED function.

Methods and results

We included consecutive CIED recipients in two centres. We tested two latest generation smartwatches (Apple Watch and Samsung Galaxy Watch) and their charging cables for potential EMI. The testing was performed under continuous electrocardiogram recording and real-time device telemetry, with nominal and ‘worst-case’ settings. In vitro magnetic field measurements were performed to assess the emissions from the tested devices, initially in contact with the probe and then at a distance of 10 cm and 20 cm. In total, 171 patients with CIEDs (71.3% pacemakers–28.7% implantable cardioverter-defibrillators) from five manufacturers were enrolled (63.2% males, 74.8 ± 11.4 years), resulting in 684 EMI tests. No EMI was identified in any patient either under nominal or ‘worst-case scenario’ programming. The peak magnetic flux density emitted by the smartwatches was similar to the background noise level (0.81 μT) even when in contact with the measuring probe. The respective values for the chargers were 4.696 μΤ and 4.299 μΤ for the Samsung and Apple chargers, respectively, which fell at the background noise level when placed at 20 cm and 10 cm, respectively.

Conclusion

Two latest generation smartwatches and their chargers resulted in no EMI in CIED recipients. The absence of EMI in conjunction with the extremely low intensity of magnetic fields emitted by these devices support the safety of their use by CIED patients.
Candida auris:a fungus with identity crisis
Authors: Vila Taissa , Sultan Ahmed S , Montelongo-Jauregui Daniel , Jabra-Rizk Mary Ann
Published: July 2020

Candida auris is a new fungal species that has puzzlingly and simultaneously emerged on five continents. Since its identification in 2009, the scientific community has witnessed an exponential emergence of infection episodes and outbreaks in healthcare facilities world-wide. Candida auris exhibits several concerning features compared to other related Candida species, including persistent colonization of skin and nosocomial surfaces, ability to resist common disinfectants and to spread rapidly among patients. Resistance to multiple drug classes and misidentification by available laboratory identification systems has complicated clinical management, and outcomes of infection have generally been poor with mortality rates approaching 68%. Currently, the origins of C. auris are unclear, and therefore, it is impossible to determine whether environmental and climactic changes were contributing factors in its recent emergence as a pathogen. Nevertheless, a robust response involving rapid diagnostics, prompt interventions and implementation of precautions, are paramount in curtailing the spread of  infections by this fungal species. Importantly, there is a pressing need for the development of new antifungal drugs. In this article, we present a brief overview highlighting some of the important aspects of C. auris epidemiology, pathogenesis and its puzzling global emergence.
Association Between Urbanicity and Dementia in China: A Population-Based Study
Authors: Luo Yanan , Zhao Yihao , Pang Lihua , Guo Chao , Liang Richard , Zheng Xiaoying
Published: July 2020

Objectives

This study investigated the relationship between urbanicity and dementia and predicted its nonlinear pattern among Chinese adults aged 50 years and older.

Methods

This study used data from the Second National Sample Survey on Disability, which was implemented from April 1 to May 31, 2006 across China. Dementia status was determined by a 2-stage process: the combination of self-reports or family members’ reports and an onsite medical diagnosis by experienced specialists based on the International Statistical Classification of Diseases and Related Health Problems 10th Revision Symptom Checklist for Mental Disorders. Logistic regression models were used to examine the relationship between urbanicity and dementia, and restricted polynomial spline regression models were plotted to examine the nonlinear exposure–response relationship of urbanicity and dementia.

Results

Logistic regression results showed that an increase of 10% in the degree of urbanization was associated with a 73% decrease in the odds of dementia after adjusting for covariates, particularly area-level socioeconomic variables. This observed association was stronger in the younger age group, and this age group difference was only present in women. Spline regression findings suggested a nonlinear exposure–response relationship between urbanicity and the odds of dementia. Areas with very high levels of urbanization were associated with increased odds of dementia.

Conclusions

These findings highlight the necessity to properly examine the nuanced relationship between urbanicity and mental health, especially for women in the younger age group. Notably, there were increased odds of dementia at very high levels of urbanicity.
Effectiveness of remdesivir in patients with COVID-19 under mechanical ventilation in an Italian ICU
Authors: Pasquini Zeno , Montalti Roberto , Temperoni Chiara , Canovari Benedetta , Mancini Mauro , Tempesta Michele , Pimpini Daniela , Zallocco Nicoletta , Barchiesi Francesco
Published: July 2020

Background

Remdesivir is a prodrug with in vitro activity against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Its clinical efficacy in patients with COVID-19 under mechanical ventilation remains to be evaluated.

Methods

This study includes patients under mechanical ventilation with confirmed SARS-CoV-2 infection admitted to the ICU of Pesaro hospital between 29 February and 20 March 2020. During this period, remdesivir was provided on a compassionate use basis. Clinical characteristics and outcome of patients treated with remdesivir were collected retrospectively and compared with those of patients hospitalized in the same time period.

Results

A total of 51 patients were considered, of which 25 were treated with remdesivir. The median (IQR) age was 67 (59–75.5) years, 92% were men and symptom onset was 10 (8–12) days before admission to ICU. At baseline, there was no significant difference in demographic characteristics, comorbidities and laboratory values between patients treated and not treated with remdesivir. Median follow-up was 52 (46–57) days. Kaplan–Meier curves showed significantly lower mortality among patients who had been treated with remdesivir (56% versus 92%, P < 0.001). Cox regression analysis showed that the Charlson Comorbidity Index was the only factor that had a significant association with higher mortality (OR 1.184; 95% CI 1.027–1.365; P = 0.020), while the use of remdesivir was associated with better survival (OR 3.506; 95% CI 1.768–6.954; P < 0.001).

Conclusions

In this study the mortality rate of patients with COVID-19 under mechanical ventilation is confirmed to be high. The use of remdesivir was associated with a significant beneficial effect on survival.
Mesoscale modelling of optical turbulence in the atmosphere: the need for ultrahigh vertical grid resolution
Authors: Basu S , Osborn J , He P , DeMarco A W
Published: July 2020

The high-fidelity modelling of optical turbulence is critical to the design and operation of a new class of emerging highly sophisticated astronomical telescopes and adaptive optics instrumentation. In this study, we perform retrospective simulations of optical turbulence over the Hawaiian islands using a mesoscale model. The simulated results are validated against thermosonde data. We focus on turbulence in the free atmosphere, above the atmospheric boundary layer. The free atmosphere is particularly important for adaptive optics performance and for sky coverage calculations and hence has significant impact on performance optimization and scheduling of observations. We demonstrate that a vertical grid spacing of 100 m or finer is needed to faithfully capture the intrinsic variabilities of observed clear air turbulence. This is a particularly timely study because the next generation of extremely large telescopes are currently under construction and their associated suite of instruments are in the design phase. Knowledge of the expected accuracy of optical turbulence simulations and real-time forecasts will enable the design teams to (i) test and develop instrument designs and (ii) formulate operational procedure.
Influence of galactic arm scale dynamics on the molecular composition of the cold and dense ISM III. Elemental depletion and shortcomings of the current physico-chemical models
Authors: Wakelam V , Iqbal W , Melisse J-P , Gratier P , Ruaud M , Bonnell I
Published: July 2020

We present a study of the elemental depletion in the interstellar medium. We combined the results of a Galactic model describing the gas physical conditions during the formation of dense cores with a full-gas-grain chemical model. During the transition between diffuse and dense medium, the reservoirs of elements, initially atomic in the gas, are gradually depleted on dust grains (with a phase of neutralization for those which are ions). This process becomes efficient when the density is larger than 100 cm−3. If the dense material goes back into diffuse conditions, these elements are brought back in the gas phase because of photo-dissociations of the molecules on the ices, followed by thermal desorption from the grains. Nothing remains on the grains for densities below 10 cm−3 or in the gas phase in a molecular form. One exception is chlorine, which is efficiently converted at low density. Our current gas–grain chemical model is not able to reproduce the depletion of atoms observed in the diffuse medium except for Cl, which gas abundance follows the observed one in medium with densities smaller than 10 cm−3. This is an indication that crucial processes (involving maybe chemisorption and/or ice irradiation profoundly modifying the nature of the ices) are missing.
The TESS light curve of the eccentric eclipsing binary 1SWASP J011351.29+314909.7 – no evidence for a very hot M-dwarf companion
Authors: Swayne Matthew I , Maxted Pierre F L , Kunovac Hodžić Vedad , Triaud Amaury H M J
Published: July 2020

A 2014 study of the eclipsing binary star 1SWASPJ011351.29+314909.7 (J0113+31) reported an unexpectedly high effective temperature for the M-dwarf companion to the 0.95-M⊙ primary star. The effective temperature inferred from the secondary eclipse depth was ∼600 K higher than the value predicted from stellar models. Such an anomalous result questions our understanding of low-mass stars and might indicate a significant uncertainty when inferring properties of exoplanets orbiting them. We seek to measure the effective temperature of the M-dwarf companion using the light curve of J0113+31 recently observed by the Transiting Exoplanet Survey Satellite (TESS). We use the pycheops modelling software to fit a combined transit and eclipse model to the TESS light curve. To calculate the secondary effective temperature, we compare the best-fitting eclipse depth to the predicted eclipse depths from theoretical stellar models. We determined the effective temperature of the M dwarf to be Teff,2 = 3208 ± 43 K, assuming log g2 = 5, [Fe/H] = −0.4, and no alpha-element enhancement. Varying these assumptions changes Teff,2 by less than 100 K. These results do not support a large anomaly between observed and theoretical low-mass star temperatures.
Does the HR 6819 triple system contain a dormant black hole? Not necessarily
Authors: Mazeh Tsevi , Faigler Simchon
Published: July 2020

A recent paper by Rivinius et al. proposed that HR 6819 is a triple system, with a distant Be star and a binary of 40-d orbit, composed of a B3 III giant and a dormant black hole (BH). We suggest that the evidence for this model is not conclusive. In an alternative model, the companion of the giant is by itself a short-period binary in, say, a ∼4-d orbit, consisting, for example, of two A0 stars. Each of the two A0 stars should contribute ${\sim}4{{\ \rm per cent}}$ of the total brightness of the system in the V band, and their spectral lines are moving due to their assumed orbital motion with an unknown period. Therefore, only a careful analysis of the observed spectra can exclude such a model. Before such an analysis is presented and upper limits for the depths of the hypothetical A0 star absorption lines are derived, the model of a hidden close pair is more probable than the BH model.
Lipid–oligonucleotide conjugates for bioapplications
Authors: Li Xiaowei , Feng Kejun , Li Long , Yang Lu , Pan Xiaoshu , Yazd Hoda Safari , Cui Cheng , Li Juan , Moroz Leonid , Sun Yujia , Wang Bang , Li Xiang , Huang Tong , Tan Weihong
Published: July 2020

Lipid–oligonucleotide conjugates (LONs) are powerful molecular-engineering materials for various applications ranging from biosensors to biomedicine. Their unique amphiphilic structures enable the self-assembly and the conveyance of information with high fidelity. In particular, LONs present remarkable potential in measuring cellular mechanical forces and monitoring cell behaviors. LONs are also essential sensing tools for intracellular imaging and have been employed in developing cell-surface-anchored DNA nanostructures for biomimetic-engineering studies. When incorporating therapeutic oligonucleotides or small-molecule drugs, LONs hold promise for targeted therapy. Moreover, LONs mediate the controllable assembly and fusion of vesicles based on DNA-strand displacements, contributing to nanoreactor construction and macromolecule delivery. In this review, we will summarize the general synthesis strategies of LONs, provide some characterization analysis and emphasize recent advances in bioanalytical and biomedical applications. We will also consider the relevant challenges and suggest future directions for building better functional LONs in nanotechnology and materials-science applications.
Smart responsive organic microlasers with multiple emission states for high-security optical encryption
Authors: Gao Zhenhua , Wang Kang , Yan Yongli , Yao Jiannian , Zhao Yong Sheng
Published: July 2020

Modern high-security cryptography and optical communication call for covert bit sequences with high coding capacity and efficient authentication. Stimuli-responsive lasing emissions with easily distinguishable readout are promising in the coding field as a novel cryptographic primitive, while the application is frequently restricted by the limited number of emission states. Here, we report a strategy of achieving multiple competitive lasing signals in responsive organic microspheres where a donor–acceptor pair was introduced. The competitive lasing from the donor and acceptor was reversibly switched by modulating the competition between the radiative rate of the donor and the rate of energy transfer, and the generated multiple lasing signals enabled a quaternary coding for recognizable cryptographic implementation. Data encryption and extraction were demonstrated using a 4 × 4 microlaser array, showing vast prospects in avoiding the disclosure of security information. The results offer a comprehensive understanding of excited-state dynamics in organic composite materials, which may play a major role in high-security optical recording and information encryption.
Discovery of recombining plasma associated with the candidate supernova remnant G189.6+3.3 with Suzaku
Authors: Yamauchi Shigeo , Oya Moe , Nobukawa Kumiko K , Pannuti Thomas G
Published: July 2020

We present the results of an X-ray spectral analysis of the northeast region of the candidate supernova remnant G189.6+3.3 with Suzaku. K-shell lines from highly ionized Ne, Mg, Si, and S were detected in the spectrum for the first time. In addition, a radiative recombining continuum (RRC) from He-like Si was clearly seen near 2.5 keV. This detection of an RRC reveals for the first time that G189.6+3.3 possesses an X-ray-emitting recombining plasma (RP). The extracted X-ray spectrum in the 0.6–10.0 keV energy band is well fitted with a model consisting of a collisional ionization equilibrium plasma component (associated with the interstellar medium) and an RP component (associated with the ejecta). The spectral feature shows that G189.6+3.3 is most likely to be a middle-aged SNR with an RP.
Factors associated with sarcopenia in institutionalized elderly
Authors: de Oliveira Neto Leônidas , de Oliveira Larissa Praça , Agrícola Pedro Moraes Dutra , de Oliveira Tavares Vagner Deuel , Gomes Igor Conterato , Sales Márcia Cristina , Lima Kenio Costa
Published: July 2020

Background

The diagnosis of sarcopenia is based on the analysis of strength, functionality and muscle mass. The objective was to verify the factors associated with sarcopenia in institutionalized elderly.

Methods

In total, 219 elderly individuals (≥60 years old) living in long-term institutions in Natal/RN were included in the study. After defining the elderly as sarcopenic or non-sarcopenic, anthropometric, biochemical, sociodemographic and health-related were analyzed. The Student t-test and Mann–Whitney test were used to analyze the quantitative, while the chi-square test was used for the qualitative variables. Finally, Poisson regression was used to provide prevalence ratios for those variables that presented differences in the bivariate analyses.

Results

Physical capacity and anthropometry were associated with sarcopenia. For each 1 cm of knee height, the elderly presented 2.71% more chance of not having sarcopenia, and eutrophic or overweight individuals (according to BMI) presented 37.71 and 91.81% chances, respectively, of not presenting sarcopenia. Elderly individuals who ambulate have a 30.08% chance of not being considered sarcopenic. In addition, biochemical and anthropometric indicators demonstrated a relationship of sarcopenia with malnutrition.

Conclusion

Sarcopenia is associated with a loss of body mass, not only selective muscle mass, and greater physical inability to ambulate.
Association of Intrapartum Risk Factors and Infant Clinical Indicators with Culture Confirmed Early Onset Neonatal Sepsis in a Secondary Care Rural Hospital in India
Authors: Gandra Sumanth , Ranga Shravan K , Hendrixson D Taylor , Nayakanti Raghuprakash R , Newland Jason G , Alvarez-Uria Gerardo , Jinka Dasaratha R
Published: July 2020

Objective

The aim of this study is to determine the association of intrapartum risk factors and infant clinical indicators using the National Institute for Health and Care Excellence (NICE) criteria with culture-positive early-onset neonatal sepsis (EONS) from a rural secondary healthcare facility where intrapartum prophylactic antibiotics are routinely administered to high-risk mothers.

Methods

A single-center prospective observational study was conducted between July 2017 and September 2018. All intramural neonates with at least one NICE criteria at less than 72 h of life, were included. Univariate logistic regression and multivariable logistic backward elimination analyses were conducted to investigate individual risk factors and predictive models for culture proven EONS.

Results

Of 236 newborns who were at risk for EONS by NICE criteria, 32 (13.8%) had positive blood cultures. Klebsiella species (n = 13, 39.4%) and Acinetobacter species (n = 11, 33.3%) were the most common isolated bacteria. In univariate analysis, the number of infant clinical indicators were associated with culture positive EONS (OR 1.36; 95% CI 1.01–1.81), but not the number of intrapartum risk factors (OR 0.76; 95% CI 0.4–1.29). The multivariate logistic regression with backward elimination procedure suggested that a model including absolute neutrophil count [adjusted OR (aOR) 0.81; 95% CI 0.72–0.92], C-reactive protein (aOR 1.24; 95% CI 1.08–1.43) and the number of clinical indicators (aOR 1.29; 95% CI 0.93–1.80) could be useful to predict culture positive EONS in our setting.

Conclusion

In this maternal and neonatal cohort, infant clinical indicators rather than intrapartum risk factors were associated with culture confirmed EONS.
Determining Associations and Estimating Effects with Regression Models in Clinical Anesthesia
Authors: Aoyama Kazuyoshi , Pinto Ruxandra , Ray Joel G. , Hill Andrea , Scales Damon C. , Fowler Robert A.
Published: July 2020

There are an increasing number of “big data” studies in anesthesia that seek to answer clinical questions by observing the care and outcomes of many patients across a variety of care settings. This Readers’ Toolbox will explain how to estimate the influence of patient factors on clinical outcome, addressing bias and confounding. One approach to limit the influence of confounding is to perform a clinical trial. When such a trial is infeasible, observational studies using robust regression techniques may be able to advance knowledge. Logistic regression is used when the outcome is binary (e.g., intracranial hemorrhage: yes or no), by modeling the natural log for the odds of an outcome. Because outcomes are influenced by many factors, we commonly use multivariable logistic regression to estimate the unique influence of each factor. From this tutorial, one should acquire a clearer understanding of how to perform and assess multivariable logistic regression.
Computer-aided Discovery of a New Nav1.7 Inhibitor for Treatment of Pain and Itch
Authors: Chandra Sharat , Wang Zilong , Tao Xueshu , Chen Ouyang , Luo Xin , Ji Ru-Rong , Bortsov Andrey V.
Published: July 2020

Background

Voltage-gated sodium channel Nav1.7 has been validated as a perspective target for selective inhibitors with analgesic and anti-itch activity. The objective of this study was to discover new candidate compounds with Nav1.7 inhibitor properties. The authors hypothesized that their approach would yield at least one new compound that inhibits sodium currents in vitro and exerts analgesic and anti-itch effects in mice.

Methods

In silico structure-based similarity search of 1.5 million compounds followed by docking to the Nav1.7 voltage sensor of Domain 4 and molecular dynamics simulation was performed. Patch clamp experiments in Nav1.7-expressing human embryonic kidney 293 cells and in mouse and human dorsal root ganglion neurons were conducted to test sodium current inhibition. Formalin-induced inflammatory pain model, paclitaxel-induced neuropathic pain model, histamine-induced itch model, and mouse lymphoma model of chronic itch were used to confirm in vivo activity of the selected compound.

Results

After in silico screening, nine compounds were selected for experimental assessment in vitro. Of those, four compounds inhibited sodium currents in Nav1.7-expressing human embryonic kidney 293 cells by 29% or greater (P < 0.05). Compound 9 (3-(1-benzyl-1H-indol-3-yl)-3-(3-phenoxyphenyl)-N-(2-(pyrrolidin-1-yl)ethyl)propanamide, referred to as DA-0218) reduced sodium current by 80% with a 50% inhibition concentration of 0.74 μM (95% CI, 0.35 to 1.56 μM), but had no effects on Nav1.5-expressing human embryonic kidney 293 cells. In mouse and human dorsal root ganglion neurons, DA-0218 reduced sodium currents by 17% (95% CI, 6 to 28%) and 22% (95% CI, 9 to 35%), respectively. The inhibition was greatly potentiated in paclitaxel-treated mouse neurons. Intraperitoneal and intrathecal administration of the compound reduced formalin-induced phase II inflammatory pain behavior in mice by 76% (95% CI, 48 to 100%) and 80% (95% CI, 68 to 92%), respectively. Intrathecal administration of DA-0218 produced acute reduction in paclitaxel-induced mechanical allodynia, and inhibited histamine-induced acute itch and lymphoma-induced chronic itch.

Conclusions

This study’s computer-aided drug discovery approach yielded a new Nav1.7 inhibitor that shows analgesic and anti-pruritic activity in mouse models.

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Cost-effectiveness Analysis of Preoperative Screening Strategies for Obstructive Sleep Apnea among Patients Undergoing Elective Inpatient Surgery
Authors: Sankar Ashwin , Dixon Peter R. , Sivanathan Lavarnan , Memtsoudis Stavros G. , de Almeida John R. , Singh Mandeep
Published: July 2020

Background

Obstructive sleep apnea is underdiagnosed in surgical patients. The cost-effectiveness of obstructive sleep apnea screening is unknown. This study’s objective was to evaluate the cost-effectiveness of preoperative obstructive sleep apnea screening (1) perioperatively and (2) including patients’ remaining lifespans.

Methods

An individual-level Markov model was constructed to simulate the perioperative period and lifespan of patients undergoing inpatient elective surgery. Costs (2016 Canadian dollars) were calculated from the hospital perspective in a single-payer health system. Remaining model parameters were derived from a structured literature search. Candidate strategies included: (1) no screening; (2) STOP-Bang questionnaire alone; (3) STOP-Bang followed by polysomnography (STOP-Bang + polysomnography); and (4) STOP-Bang followed by portable monitor (STOP-Bang + portable monitor). Screen-positive patients (based on STOP-Bang cutoff of at least 3) received postoperative treatment modifications and expedited definitive testing. Effectiveness was expressed as quality-adjusted life month in the perioperative analyses and quality-adjusted life years in the lifetime analyses. The primary outcome was the incremental cost-effectiveness ratio.

Results

In perioperative and lifetime analyses, no screening was least costly and least effective. STOP-Bang + polysomnography was the most effective strategy and was more cost-effective than both STOP-Bang + portable monitor and STOP-Bang alone in both analyses. In perioperative analyses, STOP-Bang + polysomnography was not cost-effective compared to no screening at the $4,167/quality-adjusted life month threshold (incremental cost-effectiveness ratio $52,888/quality-adjusted life month). No screening was favored in more than 90% of iterations in probabilistic sensitivity analyses. In contrast, in lifetime analyses, STOP-Bang + polysomnography was favored compared to no screening at the $50,000/quality-adjusted life year threshold (incremental cost-effectiveness ratio $2,044/quality-adjusted life year). STOP-Bang + polysomnography was favored in most iterations at thresholds above $2,000/quality-adjusted life year in probabilistic sensitivity analyses.

Conclusions

The cost-effectiveness of preoperative obstructive sleep apnea screening differs depending on time horizon. Preoperative screening with STOP-Bang followed by immediate confirmatory testing with polysomnography is cost-effective on the lifetime horizon but not the perioperative horizon. The integration of preoperative screening based on STOP-Bang and polysomnography is a cost-effective means of mitigating the long-term disease burden of obstructive sleep apnea.

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Cytotoxic mechanisms of primin, a natural quinone isolated from Eugenia hiemalis, on hematological cancer cell lines
Authors: Bigolin Alisson , Maioral Mariana F. , Stefanes Natália M. , Zatelli Gabriele A. , Philippus Ana C. , Falkenberg Miriam de B. , Santos-Silva Maria C.
Published: July 2020

Considering the high morbidity and mortality rates associated with hematological malignancies and the frequent development of drug resistance by these diseases, the search for new cytotoxic agents is an urgent necessity. The new compounds should present higher efficiency and specificity in inducing tumor cell death, be easily administered and have little or negligible adverse effects. Quinones have been reported in the literature by their several pharmacological properties, including antitumor activity, thus, the aim of this study was to investigate the cytotoxic effect of primin, a natural quinone, on hematological malignancies cell lines. Primin was highly cytotoxic against the three cell lines included in this study (K562, Jurkat and MM.1S) in a concentration- and time-dependent manner, as demonstrated by the MTT method. The compound triggered an apoptotic-like cell death, as observed by ethidium bromide/acridine orange staining, DNA fragmentation and phosphatidylserine exposure after labeling with Annexin V. Both intrinsic and extrinsic apoptosis are involved in cell death induced by primin, as well as the modulation of cell proliferation marker KI-67. The activation of intrinsic apoptosis appears to be related to a decreased Bcl-2 expression and increased Bax expression. While the increase in FasR expression signals activate extrinsic apoptosis. The results suggest that primin is a promising natural molecule that could be used in hematological malignancies therapy or as prototypes for the development of new chemotherapics.