bluuebunny/crossref_metadata_2025 huggingface dataset:
Interventionsbedürftige Epistaxis nasi nach
SARS-CoV-2-Abstrich
Authors: Martin Melanie , Greve Jens , Hoffmann Thomas K. , Hahn Janina
Published: September 2021

Einleitung Seit Mai 2020 wurden die ersten POC Tests für die
SARS-CoV-2 Diagnostik angeboten, welche mit der Notwendigkeit des
nasopharyngealen Abstrichs verbunden waren. Aufgrund des langen Arbeitskanals
durch die Nasenhaupthöhle besteht das Risiko einer Schleimhautverletzung
mit konsekutiver Epistaxis.

Methodik Wir beschreiben den Krankheitsverlauf zweier Patientinnen, bei
denen es nach extern durchgeführtem nasopharyngealen Test zu einer
massiven interventionspflichtigen Epistaxis nasi kam.

Ergebnisse Bei einer Patientin musste nach frustraner Nasentamponade eine
endonasale Blutstillung in Intubationsnarkose durchgeführt werden. Bei
einer zweiten Patientin kam es zu einer Hb-relevanten Epistaxis nasi mit
hämorrhagischem Schock. Sie wurde intubiert und beatmet
stationär übernommen.

Schlussfolgerung Der transnasale Test in der SARS-CoV-2 Diagnostik
führt in seltenen Fällen zu lebensbedrohlichen Komplikationen.
Aufgrund der weltweit über 5 Millionen täglich
durchgeführten Tests im Rahmen der aktuellen Pandemie sind
Komplikationen nicht zu vernachlässigen. Es ist unverzichtbar, dass die
den Abstrich durchführende Person die Anatomie detailliert kennt.
Alternative Testmethoden werden bezüglich ihrer Sensitivität
weiter beurteilt. Hinsichtlich der auch zukünftig bestehenden
Notwendigkeit von SARS-CoV-2-Tests ist eine weitere Etablierung alternativer und
risikoärmerer Testverfahren unerlässlich.
Oxidation of α,β-Unsaturated Ketones by Organophotocatalysis Using Rhodamine 6G under Visible Light Irradiation: Insight into the Reaction Mechanism
Authors: Yoshioka Eito , Takahashi Hiroki , Miyabe Hideto , Wanibe Hikari , Hontani Yukina , Hatsuse Kouki , Shimizu Remi , Kawashima Akira , Kohtani Shigeru
Published: September 2021

The oxidative transformation of α,β-unsaturated ketones was investigated under visible-light-induced photocatalytic conditions using rhodamine 6G as an organophotocatalyst. In this organocatalysis, the mild co-oxidant bromotrichloromethane (BrCCl3) acts not only as a quencher toward the activated photocatalyst species, having reductant properties, but also as a brominating reagent for the intermediate radicals. This study shows that bromine atom transfer from BrCCl3 to intermediate radicals is a key step in the reaction mechanism of our oxidation method.
The Impact of COVID-19 Related Disruption on Injury Rates in Elite
Men’s Domestic Cricket
Authors: Goggins Luke , Peirce Nicholas , Griffin Steve , Langley Ben , Jowitt Hannah , McKay Carly , Stokes Keith A. , Williams Sean
Published: September 2021

This study aimed to investigate the impact of COVID-19 enforced prolonged
training disruption and shortened competitive season, on in-season injury and
illness rates. Injury incidence and percent proportion was calculated for the
2020 elite men’s senior domestic cricket season and compared to a
historical average from five previous regular seasons (2015 to 2019 inclusive).
The injury profile for the shortened 2020 season was generally equivalent to
what would be expected in a regular season, except for a significant increase in
medical illness as a proportion of time loss (17% compared to historic
average of 6%) and in-season days lost (9% compared to historic
average of 3%) due to COVID-19 related instances (most notably
precautionary isolation due to contact with a confirmed or suspected COVID-19
case). There was a significant increase in the proportion of in-season days lost
to thigh injuries (24% compared to 9%) and a significant
decrease in the proportion of days lost to hand (4% compared to
12%) and lumbar spine (7% compared to 21%) injuries.
These findings enhance understanding of the impact prolonged period of training
disruption and shortened season can have on cricket injuries and the challenges
faced by practitioners under such circumstances.
The Surgeon Mentor Program: Outcomes of Total Hip Arthroplasty via the Direct Anterior Approach
Authors: Jiang Melinda , Inglis Mark , Morris David , Eardley-Harris Nathan , Wilson Christopher J.
Published: September 2021

The direct anterior approach (DAA) for total hip arthroplasty has been increasing in popularity due to potential benefits including less pain, faster recovery, decreased risk of dislocation, and a reduced length of stay. The DAA has been described by many to have a steep learning curve owing to its greater risk of complications when first using the approach. The primary aim of this study was to design and implement a specific surgeon mentor program in an attempt to reduce the learning curve of the DAA. Surgeons completed the surgical education and mentoring program designed to reduce the initial increase in complication rate when first learning the DAA in a public hospital setting. A retrospective review of clinical and radiological outcomes on the first 67 cases was then conducted. Of these, 43 cases were eligible for inclusion. The 43 patients in this study had a mean age of 66.7, BMI of 26.7, and 57% of them were female. Follow-up was between 39 and 49 months, with a mean of 46 months. There were no fractures, dislocations, or blood transfusions. One patient required revision for deep infection. The mean length of stay was 2.81 days. At 6 weeks postoperative, 86% were independently mobile, 9.3% were using a cane, and 4.7% were being weaned off a walker. The radiological assessments found a mean cup abduction of 39.9 ± 5.1 degrees, mean femoral offset of 1.6 ± 5.5 mm, and a total hip offset of 1.3 ± 7 mm greater than the contralateral hip. Patients had a mean leg length discrepancy of −0.9 ± 5.9 mm. In conclusion, a surgeon mentoring program was designed and implemented to reduce the learning curve of the DAA in our center, with satisfactory 3-year clinical and radiological outcomes achieved. This study provides preliminary support for the potential utility of the mentoring program in facilitating other centers in safely introducing the DAA into their practice without an initial increase in complication rate.
Evaporation characteristics of metallic materials for vacuum electron devices
Authors: Liu Yanwen , Wang Guojian , Tian Hong , Li Fen , Wang Xiaoxia
Published: September 2021

Evaporation properties of Monel and stainless-steel alloy materials that are widely applied in microwave vacuum electron devices have been studied by time-of-flight mass spectrometry (ToFMS) as their evaporants has an immediate impact on their lifetime and reliability. The composition and sizes of evaporants of Monel and stainless steel have been determined. Minor evaporation of Mn, Cu, and Cr in Monel and stainless steel occurred at ∼800°C, which is much lower than the melting points of Mn, Cu, and Cr, and evaporation of Mn, Cu, and Cr increased with increasing temperature. Experimental results show that ToFMS is a very fast testing method for researching metallic material evaporation. At 900°C, substantial changes occurred in the surface microstructures of Monel and stainless steel as high porosity and many grain boundaries were observed. With increasing treatment time, grain boundaries gradually became larger, decreasing material strength and leading to outgassing or even air leakage. Such phenomena have been analyzed based on relevant theory, and appropriate feasible methods for use of metallic materials have been discussed from the perspective of vacuum device design and process control.
Atomistic simulation of nanoindentation response of dual-phase nanocrystalline CoCrFeMnNi high-entropy alloy
Authors: Qiu Yuhang , Qi Yuming , Zheng Huayong , He Tengwu , Feng Miaolin
Published: September 2021

In this study, molecular dynamics (MD) simulation is adopted to explore the mechanical properties and microstructure evolution of a dual-phase CoCrFeMnNi high-entropy alloy during nanoindentation. The influence of the volume fraction of the hexagonal closed-packed (hcp) phase is considered, and the P–h curves are plotted, where the indentation depths of curves initially into the plastic stage and the maximum indentation force for each curve are significantly different. At the elastic stage, the results from MD simulations are in agreement with those of the Hertz contact theory. However, the fitting coefficient k is remarkably influenced by the hcp phase volume fraction. The correlating P–h curves of plastic deformation are investigated by analyzing the instantaneous defect structures dominated by the nucleation of Shockley partial dislocations or the movements of stacking faults. Furthermore, the microstructure evolution with the increment in indentation depth is demonstrated, and it revealed that the plastic deformation is affected by the phase structure indenter that initially contacts. Unlike the slipping process for the face-centered-cube phase, a new hcp structure grain is created through dynamic recrystallization if the hcp phase is the first phase that the indenter touches.
Deterministic and stochastic effects in spreading dynamics: A case study of bovine viral diarrhea
Authors: Galler Markus , Lüdge Kathy , Humphries Rory , Mulchrone Kieran , Hövel Philipp
Published: September 2021

Bovine viral diarrhea (BVD) is a disease in cattle with complex transmission dynamics that causes substantial economic losses and affects animal welfare. The infection can be transient or persistent. The mostly asymptomatic persistently infected hosts are the main source for transmission of the virus. This characteristic makes it difficult to control the spreading of BVD. We develop a deterministic compartmental model for the spreading dynamics of BVD within a herd and derive the basic reproduction number. This epidemiological quantity indicates that identification and removal of persistently infected animals is a successful control strategy if the transmission rate of transiently infected animals is small. Removing persistently infected animals from the herd at birth results in recurrent outbreaks with decreasing peak prevalence. We propose a stochastic version of the compartmental model that includes stochasticity in the transmission parameters. This stochasticity leads to sustained oscillations in cases where the deterministic model predicts oscillations with decreasing amplitude. The results provide useful information for the design of control strategies.
Existence of measure pseudo-almost automorphic functions and applications to impulsive integro-differential equation
Authors: Kavitha V. , Baleanu Dumitru , George Soumya , Grayna J.
Published: September 2021

This article’s main objective is to establish the measure pseudo-almost automorphic solution of an integro-differential equation with impulses. We develop the existence results based on the Banach contraction principle mapping and Krasnoselskii and Krasnoselskii–Schaefer type fixed point theorems. Finally, some examples are given to illustrate the significance of our theoretical findings.
Traveling wakefield tube: THz source powered by nonrelativistic electron beam
Authors: Schneider Mitchell E. , Jevarjian Emily , Sims Benjamin , Altmark Alexander , van der Geer Bas , Baryshev Sergey V.
Published: September 2021

High peak power, tunable, narrowband terahertz emitters are becoming sought after given their portability, efficiency, and ability to be deployed in the field for industrial, medical, and military applications. The use of accelerator systems producing THz frequencies via Cherenkov radiation, generated by passing an electron beam through a slow-wave wakefield structure, is a promising method to meet future THz requirements. To date, efforts have been dedicated to analysis and design of sources utilizing laser seeded bunched electron beam drivers with relativistic energies beyond 5 MeV. Presented here is a wakefield THz generation scheme based on passing a long quasi-dc nonrelativistic beam (200 keV) through a dielectric loaded traveling wave structure. Reduced energy allows for compactness and portability of the accelerator as the size and weight of the dielectric slow-wave structure is vanishingly small compared to the accelerator unit. The presented scheme can serve as a tunable high peak power THz source operated between 0.4 and 1.6 THz and produces power gain by a factor of five with an average efficiency of 6.8%.
Tight distance-dependent estimators for screening two-center and three-center short-range Coulomb integrals over Gaussian basis functions
Authors: Ye Hong-Zhou , Berkelbach Timothy C.
Published: September 2021

We derive distance-dependent estimators for two-center and three-center electron repulsion integrals over a short-range Coulomb potential, erfc(ωr12)/r12. These estimators are much tighter than the ones based on the Schwarz inequality and can be viewed as a complement to the distance-dependent estimators for four-center short-range Coulomb integrals and for two-center and three-center full Coulomb integrals previously reported. Because the short-range Coulomb potential is commonly used in solid-state calculations, including those with the Heyd–Scuseria–Ernzerhof functional and with our recently introduced range-separated periodic Gaussian density fitting, we test our estimators on a diverse set of periodic systems using a wide range of the range-separation parameter ω. These tests demonstrate the robust tightness of our estimators, which are then used with integral screening to calculate periodic three-center short-range Coulomb integrals with linear scaling in system size.
Multi-state harmonic models with globally shared bath for nonadiabatic dynamics in the condensed phase
Authors: Hu Zhubin , Brian Dominikus , Sun Xiang
Published: September 2021

Model Hamiltonians constructed from quantum chemistry calculations and molecular dynamics simulations are widely used for simulating nonadiabatic dynamics in the condensed phase. The most popular two-state spin-boson model could be built by mapping the all-atom anharmonic Hamiltonian onto a two-level system bilinearly coupled to a harmonic bath using the energy gap time correlation function. However, for more than two states, there lacks a general strategy to construct multi-state harmonic (MSH) models since the energy gaps between different pairs of electronic states are not entirely independent and need to be considered consistently. In this paper, we extend the previously proposed approach for building three-state harmonic models for photoinduced charge transfer to the arbitrary number of electronic states with a globally shared bath and the system–bath couplings are scaled differently according to the reorganization energies between each pair of states. We demonstrate the MSH model construction for an organic photovoltaic carotenoid–porphyrin–C60 molecular triad dissolved in explicit tetrahydrofuran solvent. Nonadiabatic dynamics was simulated using mixed quantum-classical techniques, including the linearized semiclassical and symmetrical quasiclassical dynamics with the mapping Hamiltonians, mean-field Ehrenfest, and mixed quantum-classical Liouville dynamics in two-state, three-state, and four-state harmonic models of the triad system. The MSH models are shown to provide a general and flexible framework for simulating nonadiabatic dynamics in complex systems.
Reassessment of modeling turbulence via Reynolds averaging: A review of second-moment transport strategy
Authors: Hanjalić K. , Launder B. E.
Published: September 2021

This paper examines the evolution of closing the Reynolds-averaged Navier–Stokes equations by approximating the Reynolds stresses via the second-moment transport equations themselves. This strategy first proposed by Rotta is markedly in contrast to the more usual approach of computing an effective “turbulent viscosity” to deduce the turbulent stresses as in a Newtonian fluid in laminar motion. This paper covers the main elements in the development of this approach and shows examples of applications in complex shear flows that collectively include the effects of three-dimensional straining, force fields, and time dependence that affect the flow evolution in ways that cannot be readily mimicked with an eddy viscosity model.
Complete sigmoid colon erosion by an intrauterine contraception device in an ectopic pregnancy: a case report
Authors: Sen Chuah Jun , Samad Nur Hayati Abd , Huei Tan Jih , Peng Lee Ee
Published: September 2021

ABSTRACT INTRODUCTION An intrauterine contraceptive device (IUCD) is a common contraception method used for family planning. IUCD erosion into adjacent organs is a rare but serious complication of IUCD use. CASE PRESENTATION A 41-year-old female presented to us with a leaking left ectopic pregnancy. Emergency laparotomy and left salpingectomy were performed. A copper ICUD was found intraperitoneally and part of it had completely eroded into the sigmoid colon. Sigmoid colotomy was performed and the IUCD was removed successfully. Further history revealed that the patient had her IUCD inserted 12 years previously but was forgotten. The patient was discharged well after 4 days of admission. DISCUSSION Erosion of an IUCD into the colon is uncommon and may be asymptomatic or present with bowel perforation and obstruction. There should be a high index of suspicion for pregnancy occurring among women post-IUCD insertion. A misplaced IUCD can cause chronic inflammation of the fallopian tube, which may alter tubal functionality and increase the risk of ectopic pregnancy. Family planning is commonly done in primary health care. Primary care education and counselling are essential to improve awareness of fertile women to prevent similar complications. Periodic examination of IUCD string either by users or primary health-care practitioners is crucial. Ultrasound can be advocated if there are difficulties with the insertion. An abdominal radiograph is useful and should be performed in the case of missing IUCDs.
Dim light in the evening causes coordinated realignment of circadian rhythms, sleep, and short-term memory
Authors: Tam Shu K. E. , Brown Laurence A. , Wilson Tatiana S. , Tir Selma , Fisk Angus S. , Pothecary Carina A. , van der Vinne Vincent , Foster Russell G. , Vyazovskiy Vladyslav V. , Bannerman David M. , Harrington Mary E. , Peirson Stuart N.
Published: September 2021

Significance

In modern societies, people are regularly exposed to artificial light (e.g., light-emitting electronic devices). Dim light in the evening (DLE) imposes an artificial extension of the solar day, increasing our alertness before bedtime, delaying melatonin timing and sleep onset, and increasing sleepiness in the next morning. Using laboratory mice as a model organism, we show that 2 wk of 4-h, 20-lux DLE postpones rest–activity rhythms, delays molecular rhythms in the brain and body, and reverses the diurnal pattern of short-term memory performance. These results highlight the biological impact of DLE and emphasize the need to optimize our evening light exposure if we are to avoid shifting our biological clocks.
Weaving together the diverse threads of category change
Authors: la Roi Ezra
Published: September 2021

This paper investigates category changes among imperative particles in Ancient Greek. Using diachronic evidence from the category change of the imperative ἀμέλει (amélei ‘don’t worry’ > ‘of course’) and similar imperative particles, ἄγε (áge), ἴθι (íthi), φέρε (fére), εἰπέ μοι (eipé moi) and ἰδού (idoú), this paper investigates the diachronic interdependence of intersubjectification, grammaticalization and language change in general. It does this in four ways. First, I show that intersubjectification can take place without subjectification (pace Traugott 2003: 134). Second, I detail the intersubjectification of ἀμέλει with changes in the cognitive domain (no practical > no epistemic worries), the pragmatic domain (responsively resolving > independently assuming resolved worries) and contextual conditions (creating intersubjective alignment > assuming it). Third, I tease apart the various diachronic origins of changes which have affected ἀμέλει. Finally, using contrastive evidence from parallel category changes of Ancient Greek imperative particles, I argue that whereas the imperative particles can be variously affected by structural grammaticalization changes, they all display signs of context change (as shown by illocutionary extensions to occurrence with declarative and interrogative illocutions). Thus, the diverse threads of category change can be woven together by tracing the contexts of change as well as the diachronic processes shaping them.
Microstructure-toughness relationship in the simulated CGHAZ of V-N microalloyed X80 pipeline steel
Authors: Wang Ming-Ming , Gao Xiu-Hua , Song Li-Ying , Zhu Cheng-Lin , Misra R. D. K. , Du Lin-Xiu
Published: September 2021

The microstructure evolution, hardness and impact toughness in the simulated coarse-grained heat-affected zone (CGHAZ) of a V-N microalloyed X80 pipeline steel were studied. The results indicated that the microstructure mainly consisted of bainitic ferrite, acicular ferrite and granular bainite. The area fraction and size of M/A constituents were increased with increasing heat input. As heat input increased from 15 to 60 kJ cm−1, the hardness gradually decreased from 301 to 243 HV, and impact energy decreased from 284 to 33 J. Hardness in the CGHAZ was not sensitive to heat input. When the heat input exceeded 30 kJ cm−1, the formation of coarse granular bainite and large-sized blocky M/A constituents resulted in the deterioration of impact toughness.
Constraining evolution of magnetic field strength in the dissipation region of two BL Lac objects
Authors: Fan Xu-Liang , Yan Da-Hai , Wu Qing-Wen , Chen Xu
Published: September 2021

With the assumption that the optical variability timescale is dominated by the cooling time of the synchrotron process for BL Lac objects, we estimate time dependent magnetic field strength of the emission region for two BL Lac objects. The average magnetic field strengths are consistent with those estimated from core shift measurement and spectral energy distribution modelling. Variation of magnetic field strength in the dissipation region is discovered. Variability of flux and magnetic field strength shows no clear correlation, which indicates the variation of magnetic field is not the dominant reason of the variability origin. The evolution of magnetic field strength can provide another approach to constrain the energy dissipation mechanism in jets.
Special feature of a screw vacuum-compressor ‘chamber’ model development
Authors: Mustafin T N , Yakupov R R , Khamidullin M S , Khisameev I G , Alyaev V A
Published: September 2021

Wildly using of screw vacuum pumps and vacuum-compressors (which discharge pressure is higher than atmosphere pressure) can be explained by their easy service, reliability, excellent energetic and capacity characteristic and excellent vacuum, they produce. Their future optimization can be reached by using of the working process mathematic modelling, which can takes the place of expensive experimental research (can reduce the count of it). In an engineer point of view, chamber models of the positive displacement machine are still popular and wildly used due to simple of the initial data entering, small calculation time and simple of the results’ explanation. Therefore, their development and updating are still actual goal. The chamber model accuracy are determined generally by the accuracy of leakage flow calculation through the gaps and ports and by the accuracy of heat exchange calculation inside the working chamber. This is especially important for the vacuum machines, which minimal vacuum pressure are determined by the internal leakages. The vacuum inside the working chamber can lead to not only viscosity flow, but also to molecular and mixed flows. Therefore, using only viscosity flow calculation methodises leads to the significant errors. The vacuum also leads to change the heat exchange conditions inside the working chamber. Therefore, those facts should be taken into account. This paper is dedicated to the presenting the way of the solving the problems described above.
Design, Testing and Feasibility Analysis of an Oil-Free Twin Screw Compressor with In-Chamber Flash Cooling
Authors: Stupple G
Published: September 2021

With the current aim of reducing CO2 emissions worldwide compressor efficiency is more in focus than ever before. An estimated 20% of all electricity generated worldwide is used for compressing air. Oil injected twin screw compressors form a large percentage of the total. The injected oil is used for cooling, as well as for sealing and lubrication of the rotors. Typical pressure ratios lie between 8:1 and 16:1. There are many investigations being conducted into oil-free screw technology for specific applications requiring no oil carry over. In this presentation we will take a close look into the possibility of producing a single stage oil-free twin-screw compressor operating at a pressure ratio of 8:1 and using evaporated water for cooling. The main objective in this case is to improve compressor efficiency. Additionally, we will compare efficiency results with a state-of-the-art single stage oil injected twin screw compressor. Previous results from an earlier paper by the author and team from City University of London on CFD analysis of a similar system are taken as the basis. Further simulated calculations using SCORG for the actual case in question allow preliminary performance analysis using the multi-domain chamber model. From simulation we can see that the oil drag force acting on the rotors forms a significant part of the total power requirement. It is therefore suggested that an oil-free solution will achieve improved specific power. To confirm this concept, verify the simulated calculations and understand the heat transfer process in the compression chamber more fully, experimental analysis was undertaken.
Maxwell velocity slip and Smoluchowski temperature jump boundary condition for ANSYS CFX
Authors: Jünemann T. , Pleskun H. , Brümmer A.
Published: September 2021

Multi-dimensional numeric flow simulation is a common but non-trivial approach to simulate the operation behavior of screw machines. Current challenges of computational fluid dynamics (CFD) simulations of screw machines are especially related to turbulence modelling and meshing. An adaption of CFD simulations to screw vacuum pumps is difficult since the Navier-Stokes equations have limited validity for low pressure regimes. However, the scope of application can be extended to higher Knudsen numbers (e.g. lower pressure regimes) by the use of velocity slip and temperature jump boundary conditions at solid surfaces. Even if the complete simulation of screw vacuum pumps is still challenging, these boundary conditions can be used to examine isolated effects like clearance flows or inhomogeneous pressure distributions in working chambers. A common commercial CFD-Solver is ANSYS CFX, which also has been successfully applied to screw machines, but it does not provide a Maxwell velocity slip and a Smoluchowski temperature jump boundary condition. In the presented work these boundary conditions are implemented in Ansys CFX using user-defined expressions in a similar way as it has been implemented in the rhoCentralFOAM solver of the open source toolbox OpenFOAM. The boundary conditions are validated by comparison with stationary OpenFOAM results, DSMC results and measurements for a hypersonic plate flow. In addition, the boundary conditions are verified by experimental and DSMC results of a gas flow in a clearance between a rotational shaft and a plane counter plate.
Development of accurate and widely applicable compressor performance maps
Authors: Lee Cheng-Yi , Cao Tao , Hwang Yunho , Radermacher Reinhard , Shaffer Scott
Published: September 2021

The compressor performance map provides critical information, including mass flow rate, power consumption, capacities, and operating current. The map can be applied to an alternative efficiency determination method (AEDM) for HVAC&R products. However, most of the existing maps have a low prediction accuracy under low ambient temperature heating modes, as such conditions were not thoroughly considered when maps were generated. This paper provides a comprehensive study of a fixed speed compressor performance under a wide range of operating conditions, including the AHRI 210/240 standard conditions. The test matrix was developed based on realistic heat pump system operating conditions. We then quantified the existing performance map’s prediction inaccuracy, particularly under the low ambient temperature heating modes. Driven by the significant deviation at lower ambient temperature conditions, a comprehensive performance map was generated based on the test results. We also found that one polynomial equation could simultaneously fulfill the needs for predicting the compressor performance under both the cooling and heating modes. Furthermore, the accuracy has improved significantly from 63% to 2% regarding the relative maximum prediction errors over existing performance maps. It suggests that to increase prediction accuracy when using the AEDM, one must provide a suitable superheat model in the capacity simulation of the heat pump systems with the fixed speed compressor.
Assessing the performance limits of a variable-speed residential heat pump system
Authors: Brehm John K. , Augustine David , Ziviani Davide , Groll Eckhard A.
Published: September 2021

Most of the ducted split-type heat pump systems in the world feature fixed-speed compressors and fans. To meet forthcoming minimum energy rating requirements, reduce operational costs of the heat pump, and increase environmental sustainability, the efficiency of heat pump systems must be improved. Variable-speed equipment offers significant advantages for load modulation and has the ability to increase the seasonal performance significantly. Additionally, novel electrical motor technologies, such as permanent magnet (PM) motors can reduce the power consumption of the drives by up to 25-55% compared to the widely used permanent split capacitor (PSC) motor.

In this study, a ducted fixed-speed heat pump system with a cooling capacity of 17.6 kW and a seasonal coefficient of performance (SCOP) rating of 4.11 is analyzed to quantify the theoretical performance limits that could be obtained by increasing the motor efficiency of the condenser fan, the evaporator fan and the compressor. Furthermore, the performance increase by replacing the fixed-speed components with variable-speed equipment is evaluated. A detailed charge-sensitive system simulation model that was previously developed by the authors and validated using experimental data obtained with the same unit was employed to carry out parametric studies to evaluate the impact of variable-speed compressor and indoor/outdoor fans on the SCOP rating.

The study showed a 0.9% improvement of SCOP with every percentage increase of compressor motor efficiency. The dependence of the evaporator fan and condenser fan motor efficiency on SCOP was lower, but considering the generally low motor efficiencies of these components, a noticeable efficiency gain can be achieved. In variable-speed equipment, the motor efficiency of the component at minimum operational point was the significant factor on SCOP. The motor efficiency at intermediate and maximum speed had only marginal effects on the SCOP. This showed the importance of equipment with high motor efficiencies at low speeds for ducted split-system heat pumps. The change of the fixed-speed system to a fully variable-speed heat pump resulted in a high gain of SCOP, proving the superiority of a variable-speed system. Overall, the model predicted an SCOP gain of 35% when changing the system to a fully variable system with state-of-the-art high efficient motors.
Analysis and Optimization of Over Compression for Rotary Cylinder Compressor Based on PV Test
Authors: Hu YS , Wei H J , Xu J , Du Z C , Zhang P L , Ren L P
Published: September 2021

Rotary cylinder compressor is a novel positive displacement compressor. Theoretical analysis shows that the compressor may have large over compression loss. Based on PV test, the over compression characteristics of rotary cylinder compressor was analyzed, and the over compression loss accounts for 5.5% of the indicated power. The over compression was optimized, and the optimized over compression loss is only 0.5% of the indicated power. By further comparing the energy efficiency improvement of the whole compressor, it is found that the improvement effect is equivalent to that of the over compression, and the effectiveness of the scheme is confirmed.
Reducing the noise from the cavity by tuning the compressor’s oil level
Authors: Martins Paulo
Published: September 2021

This paper proposes a unified solution for noise of two different versions of the same compressor. First, the problem was identified as a high noise in 1kHz third-octave band from the version using R134a refrigerant and 1.25kHz band from R600a version. The first hypothesis was the noise coming from the motor through shifting frequency, which would explain the different frequency ranges for different refrigerants. However, this was debunked experimentally, and results are shown in this paper. The other hypothesis was the noise coming from the cavity. This was proved to be the problem’s root cause and this paper shows the simulated and experimental results which corroborates the inference. Therefore, we propose a single solution for both versions by using an optimized amount of oil, to control the cavity volume.
Enhanced absorption and EQE of Si MSM photodiodes with integrated periodic arrays of holes
Authors: Gou Jun , Xie Zheyuan , Yu He , Liu Xianchao , Wang Jun
Published: September 2021

In order to enhance the absorption of thin Si film, cylindrical-shaped holes arranged in square and hexagonal lattices with different designs of hole diameter, depth and period are integrated in the surface of Si films with a thickness of 1.5 μm and 2.5 μm on either bulk Si or SOI substrate. At the wavelengths between 800 ~ 950 nm, light bending and absorption enhancement of Si film with integrated hole array is analyzed by FDTD simulation. Hole array with a period similar to the wavelength and a diameter/period ratio around 0.7 enables a higher absorption of Si film. Si film with cylindrical-shaped holes in hexagonal lattice with a Si thickness of 1.5 μm and a hole depth of 250 nm provides an absorption of 43.16 % at 850 nm wavelength on a SiO2 substrate. Nanostructured Si MSM photodiodes are fabricated by integrating periodic arrays of holes in 1.5 μm thin absorption regions between metal fingers. The EQE is enhanced to 61 % at 850 nm, while the photodiodes without holes show only 23 %.
Millikelvin temperature cryo-CMOS multiplexer for scalable quantum device characterisation
Authors: Potočnik Anton , Brebels Steven , Verjauw Jeroen , Acharya Rohith , Grill Alexander , Wan Danny , Mongillo Massimo , Li Ruoyu , Ivanov Tsvetan , Van Winckel Steven , Mohiyaddin Fahd A , Govoreanu Bogdan , Craninckx Jan , Radu Iuliana P
Published: September 2021

Quantum computers based on solid state qubits have been a subject of rapid development in recent years. In current noisy intermediate-scale quantum technology, each quantum device is controlled and characterised through a dedicated signal line between room temperature and base temperature of a dilution refrigerator. This approach is not scalable and is currently limiting the development of large-scale quantum system integration and quantum device characterisation. Here we demonstrate a custom designed cryo-CMOS multiplexer operating at 32 mK. The multiplexer exhibits excellent microwave properties up to 10 GHz at room and millikelvin temperatures. We have increased the characterisation throughput with the multiplexer by measuring four high-quality factor superconducting resonators using a single input and output line in a dilution refrigerator. Our work lays the foundation for large-scale microwave quantum device characterisation and has the perspective to address the wiring problem of future large-scale quantum computers.
Achieving robustness to aleatoric uncertainty with heteroscedastic Bayesian optimisation
Authors: Griffiths Ryan-Rhys , A Aldrick Alexander , Garcia-Ortegon Miguel , Lalchand Vidhi , Lee Alpha A
Published: September 2021

Bayesian optimisation is a sample-efficient search methodology that holds great promise for accelerating drug and materials discovery programs. A frequently-overlooked modelling consideration in Bayesian optimisation strategies however, is the representation of heteroscedastic aleatoric uncertainty. In many practical applications it is desirable to identify inputs with low aleatoric noise, an example of which might be a material composition which displays robust properties in response to a noisy fabrication process. In this paper, we propose a heteroscedastic Bayesian optimisation scheme capable of representing and minimising aleatoric noise across the input space. Our scheme employs a heteroscedastic Gaussian process surrogate model in conjunction with two straightforward adaptations of existing acquisition functions. First, we extend the augmented expected improvement heuristic to the heteroscedastic setting and second, we introduce the aleatoric noise-penalised expected improvement (ANPEI) heuristic. Both methodologies are capable of penalising aleatoric noise in the suggestions. In particular, the ANPEI acquisition yields improved performance relative to homoscedastic Bayesian optimisation and random sampling on toy problems as well as on two real-world scientific datasets. Code is available at: https://github.com/Ryan-Rhys/Heteroscedastic-BO
Loop diuretic use following fluid resuscitation in the critically ill
Authors: Alaskar Mashael A , Brown Joshua D , Voils Stacy A , Vouri Scott M
Published: September 2021

Purpose

To identify the incidence of continuation of newly initiated loop diuretics upon intensive care unit (ICU) and hospital discharge and identify factors associated with continuation.

Methods

This was a single-center retrospective study using electronic health records in the setting of adult ICUs at a quaternary care academic medical center. It involved patients with sepsis admitted to the ICU from January 1, 2014, to June 30, 2019, who received intravenous fluid resuscitation. The endpoints of interest were (1) the incidence of loop diuretic use during an ICU stay following fluid resuscitation, (2) continuation of loop diuretics following transition of care, and (3) potential factors associated with loop diuretic continuation after transition from the ICU.

Results

Of 3,591 patients who received intravenous fluid resuscitation for sepsis, 39.4% (n = 1,415) were newly started on loop diuretics during their ICU stay. Among patients who transitioned to the hospital ward from the ICU, loop diuretics were continued in 33% (388/1,193) of patients. At hospital discharge, 13.4% (52/388) of these patients were prescribed a loop diuretic to be used in the outpatient setting. History of liver disease, development of acute kidney injury, being on vasopressors while in the ICU, receiving blood products, and receiving greater than 90 mL/kg of bolus fluids were significant potential factors associated with loop diuretic continuation after transition from the ICU.

Conclusion

New initiation of loop diuretics following intravenous fluid resuscitation in patients with sepsis during an ICU stay is a common occurrence. Studies are needed to assess the effect of this practice on patient outcomes and resource utilization.
Using a Digital Implant Catalog Improves Data Quality and Reduces Administrative Burden in the Dutch Breast Implant Registry
Authors: Barati Nariman , Vrolijk J Juliët , Becherer Babette E , van Bommel Annelotte C M , Hommes Juliëtte E , Mureau Marc A M , van der Hulst René R J W , Young-Afat Danny A , Rakhorst Hinne A
Published: September 2021

Background

Correct registration of implant characteristics is essential to monitor implant safety within implant registries. Currently, in the nationwide Dutch Breast Implant Registry (DBIR), these characteristics are being registered manually by plastic surgeons, resulting in administrative burden and potentially incorrect data entry.

Objectives

This study evaluated the accuracy of manually registered implant data, possible consequences of incorrect data, and the potential of a Digital Implant Catalog (DIC) on increasing data quality and reducing the administrative burden.

Methods

Manually entered implant characteristics (fill, shape, coating, texture) of newly inserted breast implants in the DBIR, from 2015 to 2019, were compared with the corresponding implant characteristics in the DIC. Reference numbers were employed to match characteristics between the 2 databases. The DIC was based on manufacturers’ product catalogs and set as the gold standard.

Results

A total of 57,361 DBIR records could be matched with the DIC. Accuracy of implant characteristics varied from 70.6% to 98.0%, depending on the implant characteristic. The largest discrepancy was observed for “texture” and the smallest for “coating.” All manually registered implant characteristics resulted in different conclusions about implant performance compared with the DIC (P < 0.01). Implementation of the DIC reduced the administrative burden from 14 to 7 variables (50%).

Conclusions

Implementation of a DIC increases data quality in the DBIR and reduces the administrative burden. However, correct registration of reference numbers in the registry by plastic surgeons remains key for adequate matching. Furthermore, all implant manufacturers should be involved, and regular updates of the DIC are required.
PKSPS: a novel method for predicting kinase of specific phosphorylation sites based on maximum weighted bipartite matching algorithm and phosphorylation sequence enrichment analysis
Authors: Guo Xinyun , He Huan , Yu Jialin , Shi Shaoping
Published: September 2021

With the development of biotechnology, a large number of phosphorylation sites have been experimentally confirmed and collected, but only a few of them have kinase annotations. Since experimental methods to detect kinases at specific phosphorylation sites are expensive and accidental, some computational methods have been proposed to predict the kinase of these sites, but most methods only consider single sequence information or single functional network information. In this study, a new method Predicting Kinase of Specific Phosphorylation Sites (PKSPS) is developed to predict kinases of specific phosphorylation sites in human proteins by combining PKSPS-Net with PKSPS-Seq, which considers protein–protein interaction (PPI) network information and sequence information. For PKSPS-Net, kinase–kinase and substrate–substrate similarity are quantified based on the topological similarity of proteins in the PPI network, and maximum weighted bipartite matching algorithm is proposed to predict kinase–substrate relationship. In PKSPS-Seq, phosphorylation sequence enrichment analysis is used to analyze the similarity of local sequences around phosphorylation sites and predict the kinase of specific phosphorylation sites (KSP). PKSPS has been proved to be more effective than the PKSPS-Net or PKSPS-Seq on different sets of kinases. Further comparison results show that the PKSPS method performs better than existing methods. Finally, the case study demonstrates the effectiveness of the PKSPS in predicting kinases of specific phosphorylation sites. The open source code and data of the PKSPS can be obtained from https://github.com/guoxinyunncu/PKSPS.
XGBLC: an improved survival prediction model based on XGBoost
Authors: Ma Baoshan , Yan Ge , Chai Bingjie , Hou Xiaoyu
Published: September 2021

Motivation

Survival analysis using gene expression profiles plays a crucial role in the interpretation of clinical research and assessment of disease therapy programs. Several prediction models have been developed to explore the relationship between patients’ covariates and survival. However, the high-dimensional genomic features limit the prediction performance of the survival model. Thus, an accurate and reliable prediction model is necessary for survival analysis using high-dimensional genomic data.

Results

In this study, we proposed an improved survival prediction model based on XGBoost framework called XGBLC, which used Lasso-Cox to enhance the ability to analyze high-dimensional genomic data. The novel first- and second-order gradient statistics of Lasso-Cox were defined to construct the loss function of XGBLC. We extensively tested our XGBLC algorithm on both simulated and real-world datasets, and estimated the performance of models with 5-fold cross-validation. Based on 20 cancer datasets from The Cancer Genome Atlas (TCGA), XGBLC outperforms five state-of-the-art survival methods in terms of C-index, Brier score and AUC. The results show that XGBLC still keeps good accuracy and robustness by comparing the performance on the simulated datasets with different scales. The developed prediction model would be beneficial for physicians to understand the effects of patient’s genomic characteristics on survival and make personalized treatment decisions.

Availability and implementation

The implementation of XGBLC algorithm based on R language is available at: https://github.com/lab319/XGBLC

Supplementary information

Supplementary data are available at Bioinformatics online.
Multiomix: a cloud-based platform to infer cancer genomic and epigenomic events associated with gene expression modulation
Authors: Camele Genaro , Menazzi Sebastian , Chanfreau Hernán , Marraco Agustin , Hasperué Waldo , Butti Matias D , Abba Martin C
Published: September 2021

Motivation

Large-scale cancer genome projects have generated genomic, transcriptomic, epigenomic and clinicopathological data from thousands of samples in almost every human tumor site. Although most omics data and their associated resources are publicly available, its full integration and interpretation to dissect the sources of gene expression modulation require specialized knowledge and software.

Results

We present Multiomix, an interactive cloud-based platform that allows biologists to identify genetic and epigenetic events associated with the transcriptional modulation of cancer-related genes through the analysis of multi-omics data available on public functional genomic databases or user-uploaded datasets. Multiomix consists of an integrated set of functions, pipelines and a graphical user interface that allows retrieval, aggregation, analysis and visualization of different omics data sources. After the user provides the data to be analyzed, Multiomix identifies all significant correlations between mRNAs and non-mRNA genomics features (e.g. miRNA, DNA methylation and CNV) across the genome, the predicted sequence-based interactions (e.g. miRNA–mRNA) and their associated prognostic values.

Availability and implementation

Multiomix is available at https://www.multiomix.org. The source code is freely available at https://github.com/omics-datascience/multiomix.

Supplementary information

Supplementary data are available at Bioinformatics online.