bluuebunny/crossref_metadata_2025 huggingface dataset:
Reducing Vocal Fatigue With Bone Conduction Devices: Comparing Forbrain and Sidetone Amplification
Authors: Nudelman Charles , Udd Daniela , Åhlander Viveka Lyberg , Bottalico Pasquale
Published: October 2023

Purpose:

Altered auditory feedback research aims to identify methods to strengthen speakers' awareness of their own voicing behaviors, diminish their perception of vocal fatigue, and improve their voice production. This study aims to compare the effects of two bone conduction devices that provide altered auditory feedback.

Method:

Twenty participants (19–33 years old, age:
M
[
SD
] = 25.5 [3.85] years) participated in a vocal loading task using a standard Forbrain device that provides filtered auditory feedback via bone conduction and a modified Forbrain device that provides only sidetone amplification, and a control condition with no device was also included. They rated their vocal fatigue on a visual analog scale every 2 min during the vocal loading task. Additionally, pre- and postloading voice samples were analyzed for acoustic voice parameters.

Results:

Across all participants, the use of bone conduction–altered auditory feedback devices resulted in a lower vocal fatigue when compared to the condition with no feedback. During the pre- and postvoice samples, the sound pressure level decreased significantly during feedback conditions. During feedback conditions, spectral mean and standard deviation significantly decreased, and spectral skew significantly increased.

Conclusion:

The results promote bone conduction as a possible preventative tool that may reduce self-reported vocal fatigue and compensatory voice production for healthy individuals without voice disorders.
Black hole masses for 14 gravitationally lensed quasars
Authors: Melo A. , Motta V. , Mejía-Restrepo J. , Assef R. J. , Godoy N. , Mediavilla E. , Falco E. , Kochanek C. S. , Ávila-Vera F. , Jerez R.
Published: October 2023

Aims. We have estimated black hole masses (MBH) for 14 gravitationally lensed quasars using Balmer lines; we also provide estimates based on MgII and CIV emission lines for four and two of them, respectively. We compared these estimates to results obtained for other lensed quasars.

Methods. We used spectroscopic data from the Large Binocular Telescope (LBT), Magellan, and the Very Large Telescope (VLT) to measure the full width at half maximum of the broad emission lines. Combined with the bolometric luminosity measured from the spectral energy distribution, we estimated MBH values and provide the uncertainties, including uncertainties from microlensing and variability.

Results. We obtained MBH values using the single-epoch method from the Hα and/or Hβ broad emission lines for 14 lensed quasars, including the first-ever estimates for QJ0158−4325, HE0512−3329, and WFI2026−4536. The masses are typical of non-lensed quasars of similar luminosities, as are the implied Eddington ratios. We have thus increased the sample of lenses with MBH estimates by 60%.
G189.6+03.3: The first complete X-ray view provided by SRG/eROSITA
Authors: Camilloni Francesco , Becker Werner
Published: October 2023

Context. G189.6+03.3 and IC443 are two examples of supernova remnants (SNRs) located in a region rich in gas and dust, and spatially close to the HII region S249. So far, the actual shape of IC443 is believed to be given by the past action of multiple supernova (SN) explosions, while a third unrelated SN might have originated G189.6+03.3.

Aims. Although the IC443 nebula has been extensively observed in several bands, on the contrary, the nearby and much weaker SNR G189.6+03.3, discovered in 1994 with ROSAT, has received very little attention. Given the relatively large extent of this second remnant, the new dataset provided by the X-ray telescope eROSITA on board the Spectrum Roentgen Gamma mission provides a unique opportunity to characterize it more in detail.

Methods. We provide a full spectral characterization of G189.6+03.3 emission for the first time, together with new images covering the whole remnant. As one of the leading hypotheses is that its emission partially overlaps with the emission from IC443, we test this scenario by dividing the remnant into several regions from which we extracted the spectra.

Results. The new X-ray images provided by eROSITA show an elongated structure. Together with the detection of supersolar abundances of O, Mg, Ne, and Si and a subsolar abundance of Fe, these features could be an indication of a faint SN explosion. The X-ray spectra also highlight the presence of a 0.7 keV plasma component across all of the regions, together with an almost uniform column density.

Conclusions. The ubiquitous presence of the 0.7 keV plasma component is a strong indication that G189.6+03.3 completely overlaps with IC443. We propose that the progenitors of G189.6+03.3 and IC443 could have been expelled from the same binary or multiple system, and this originated two explosions at different times and in different positions.
Astronomical CH3+ rovibrational assignments
Authors: Changala P. Bryan , Chen Ning L. , Le Hai L. , Gans Bérenger , Steenbakkers Kim , Salomon Thomas , Bonah Luis , Schroetter Ilane , Canin Amélie , Martin-Drumel Marie-Aline , Jacovella Ugo , Dartois Emmanuel , Boyé-Péronne Séverine , Alcaraz Christian , Asvany Oskar , Brünken Sandra , Thorwirth Sven , Schlemmer Stephan , Goicoechea Javier R. , Rouillé Gaël , Sidhu Ameek , Chown Ryan , Van De Putte Dries , Trahin Boris , Alarcón Felipe , Berné Olivier , Habart Emilie , Peeters Els
Published: October 2023

Context. The methyl cation (CH3+) has recently been discovered in the interstellar medium through the detection of 7 μm (1400 cm−1) features toward the d203-506 protoplanetary disk by the JWST. Line-by-line spectroscopic assignments of these features, however, were unsuccessful due to complex intramolecular perturbations preventing a determination of the excitation and abundance of the species in that source.

Aims. Comprehensive rovibrational assignments guided by theoretical and experimental laboratory techniques provide insight into the excitation mechanisms and chemistry of CH3+ in d203-506.

Methods. The rovibrational structure of CH3+ was studied theoretically by a combination of coupled-cluster electronic structure theory and (quasi-)variational nuclear motion calculations. Two experimental techniques were used to confirm the rovibrational structure of CH3+:(1) infrared leak-out spectroscopy of the methyl cation, and (2) rotationally resolved photoelectron spectroscopy of the methyl radical (CH3). In (1), CH3+ ions, produced by the electron impact dissociative ionization of methane, were injected into a 22-pole ion trap where they were probed by the pulses of infrared radiation from the FELIX free electron laser. In (2), neutral CH3, produced by CH3NO2 pyrolysis in a molecular beam, was probed by pulsed-field ionization zero-kinetic-energy photoelectron spectroscopy.

Results. The quantum chemical calculations performed in this study have enabled a comprehensive spectroscopic assignment of the v2+ and v4+ bands of CH3+ detected by the JWST. The resulting spectroscopic constants and derived Einstein A coefficients fully reproduce both the infrared and photoelectron spectra and permit the rotational temperature of CH3+ (T = 660 ± 80 K) in d203-506 to be derived. A beam-averaged column density of CH3+ in this protoplanetary disk is also estimated.
The Role of Organic Nutrients on Growth and Nutrient Uptake of Indigofera tinctoria L. in Agroforestry Systems
Authors: Setyaningrum D , Budiastuti M T S , Purnomo D , Adi R K
Published: October 2023

Indigofera tinctoria contains secondary metabolites, namely indican, as a precursor for natural blue dye. Indican growth and precursors are highly dependent on environmental conditions, namely light intensity and nutrition. This study aims to examine the role of organic fertilizers on the growth and uptake of Indigofera tinctoria nutrients in agroforestry systems. The study was conducted using a completely randomized block design with a two-factor nested pattern. Shade trees as a nesting factor with three levels of sengon, durian and mixed trees (sengon, suren and teak). Type of organic fertilizer as a nested factor with 4 levels, namely without fertilizer, cow manure, goat manure and chicken manure. Repeat 3 times. The light intensity received by the plants under the sengon trees was 47308.33 lux, durian 10250 lux, mixed trees 21491.67 lux. Nested shade trees affect growth and nutrient uptake and nitrate reductase. The highest root biomass and nitrate reductase were under the sengon trees. The type of organic fertilizer nested in shade tree species affects growth and nitrogen nutrient uptake. Chicken organic fertilizer showed the highest number of leaves, plant biomass and nitrate reductase. Efforts to optimize the yield and production of nutrient uptake are planting in low light intensity around 10250 lux with fertilization.
Characteristics of Maco Fish (Leiognathidae Spelendes) Using Coconut Shell Liquid Smoke as A Natural Preservative
Authors: Budaraga I K , Hermalena L , Ahsan I
Published: October 2023

The goal of this study is to determine the effect of purple sweet potato flour and potato starch on the quality of steamed brownies, as well as the optimal amount of purple sweet potato flour and potato flour to add in order to achieve consumer quality standards for brownies. This is in accordance with sustainable food innovation, which provides food security and nutrition while taking into account economic, social, and environmental factors, such as enhancing the nutritional value of food products by sourcing alternative ingredients. In this study, a completely randomized design (CRD) with 5 treatment levels and 3 replications was used. The observational data was examined using ANOVA, and DNMRT was assessed at a 1% significance level. Purple sweet potato flour was compared to potato flour A=100:0, B=70:30, C=50:50, D=30:70, and E=0:100 in this study. The water content, ash content, fat content, total sugar content, and antioxidant activity of steamed brownies produced from purple sweet potato flour and potato flour were shown to be significant. According to the results of organoleptic and physicochemical tests, the steamed brownies made from purple sweet potato flour and potato flour had the highest water content (27.14%), ash content (1.23%), fat content (22.13%), total sugar content (4.17%), and antioxidant activity (60.33%).
Factors Affecting The Economic Impact of Livestock Assistance in Palopo City, Indonesia
Authors: Harahap Burhanuddin , Widodo Wahyu , Risal Muhammad , Syafruddin  , Zalizar Lili , Sutanto Adi , Sapar  , Iswahyudi  , Mujianto  , Purnomo Hari
Published: October 2023

With assistance to the community, both in the form of livestock and infrastructure, it can improve economic levels through additional income from the livestock they manage. With the main function of agricultural extension officers, characteristics of the suitability of assistance received are expected to be a guideline for the Palopo City government. This research was conducted with descriptive quantitative explanatory techniques, and then the data collected using a questionnaire was processed using Excel Microsoft and processed using variant-based statistical analysis, namely SEM PLS. The results of this study with SEM analysis found that the group of breeders who received assistance from the Palopo City government showed the influence of agricultural extension officers on the effectiveness of the sustainability of the economic impact of the results obtained by 16.8%, the influence of aid characteristics on the effectiveness of the sustainability of the economic impact of the results obtained by 5%, the influence of group dynamics on the effectiveness of the sustainability of the economic impact of the results obtained by 84.4%, while the overall influence of variables on the effectiveness of the sustainability of the economic impact of the results obtained by 90.2%.
Integrated Palm Oil and Livestock Farming Enhances Productivity in Central Kalimantan
Authors: Utomo BN , Widjaja E , Erlambang Y P
Published: October 2023

This study, conducted in Kotawaringin Barat and Lamandau Districts of Central Kalimantan, aimed to investigate the patterns and implications of integrating oil palm cultivation with livestock farming. Utilizing qualitative research methods, including interviews and direct observations, three distinct integration patterns were identified: integrated (33.33%), semi-integrated (66.67%), and semi-integrated partnership (8.33%). The integrated pattern encompasses a closed-cycle system involving oil palm cultivation, cattle raising, complete feed processing, and organic fertilizer production. In contrast, the semi-integrated pattern harnesses only solid palm oil by-products for cattle feed and fertilizer blends, while the semi-integrated partnership involves collaborations between private palm oil entities and farmer groups, facilitating cattle and feed support. Remarkably, the application of produced organic fertilizer increased palm oil productivity by approximately 25% and yielded a benefit-cost (R/C) ratio of 4.0 for horticultural crops. Monthly organic fertilizer production ranged between 1-20 tons, with distribution across palm oil (33.3%), horticultural crops (8.3%), and other crops (58.3%). Additionally, liquid organic fertilizer production spanned 1000-4000 liters/month. The integrated approach, rooted in the palm oil sector, has led to the emergence of sustainable commercial units that bolster economic growth. Given its eco-friendly and popular adoption, formal legal backing from local authorities and further engagement between palm oil enterprises and farmer groups is recommended to ensure longevity and broader implementation.
Prediction of PM10 Level During High Particulate Event in Malaysia Using Modified Model
Authors: A Rahim Nur Alis Addiena , Mohamed Noor Norazian , Mohd Jafri Izzati Amani , Ul Saufie Ahmad Zia , Madalina Boboc
Published: October 2023

Particulate matter (PM10) is one of the key indicator of air quality index (API) during high particulate event (HPE). PM10 can cause adverse effect on human health and environment; hence, it is important to develop a reliable and accurate predictive model to be used as forecasting tool to alarm the citizen especially during HPE. This study aims to develop a modified Quantile Regression (QR) model to forecast the PM10 concentration during HPE in Malaysia. The performances of three predictive models namely Multiple Linear Regression (MLR), Quantile Regression (QR) and a modified QR models i.e. combination of QR with Relief-based were compared. The hourly dataset of PM10 concentration with other gaseous pollutants and weather parameters at Klang from the year with severe haze event in Malaysia (1997, 2005, 2013 and 2015) were obtained from Department of Environment (DOE) Malaysia. Three performance measures namely Mean Absolute Error (MAE), Normalised Absolute Error (NAE) and Root Mean Squared Error (RMSE) were calculated to evaluate the accuracy of the predictive models. This study found that the Relief-QR model showed the best performance compared to MLR and QR models. The prediction of future PM10 concentration is very important because it can aid the local authorities to implement precautionary measures to limit the impact of air pollution.
Critical Success Factors Affecting Labour Productivity in Building Sector Projects
Authors: Hussain Khahro Qasim , Yasmin Zainun Noor , Haleem Shaikh Haseeb , Hussain Khahro Shabir
Published: October 2023

Labour productivity has been the topic of study since last few decades due to its great contribution in the project success and organization’s growth. Various factors causing poor productivity of labour have been identified by several re-searchers worldwide. Labour productivity has been one of the least studied areas for the building sector projects within the construction industry of Pakistan. The main aim of this article is to review the previous studies since last one decade and identify the critical factors affecting labour productivity in building sector projects. To achieve the aim, a questionnaire survey based on the identified factors was carried out. The data obtained from 133 successfully returned questionnaires, was analysed by using Average Index (AI) method with the help of Statistical Package for the Social Sciences (SPSS). The findings of this research highlight 15 topmost factors affecting labour productivity including Shortage of materials at first, followed by Shortage of equipment, Lack of supervision, low wages given by employer, old and inefficient equipment, overtime, delays in salary payments, Experience of workers, rewards mechanism, reworks, height of working place, improper work planning, age of the worker, Intensity of lighting and ventilation and weather conditions respectively. The study also gives some suggestions and recommendations to overcome the labour productivity issue. This paper will help the construction stakeholders and researchers as guideline to focus on the key factors that affect the la-bour productivity in building sector projects, which ultimately have been reducing the project’s success and hindering the organizational growth as well.
Introducing Sustainable Intervention Strategies of Operation Planning and Environment Design to Activate Void Areas on the Urban Fringe
Authors: Xu Jiajun , Wu Dongzi , Wang Hongtao , Fong Chng Saun
Published: October 2023

Vacant and abandoned spaces were increasingly recognised as a major obstacle to urban revitalisation. How to intervene sustainably in urban void areas became a challenge. This paper presented a new theoretical framework for sustainable operation and design by reflecting and innovating on existing studies through a literature review and classification. The framework for sustainable operation planning included operational theme and promotion, management and maintenance, effective resource utilisation and sustainable digital technology. The framework for sustainable environment design included function and layout, ecosystem management, construction material and art design aesthetic. In the context of the sustainability framework, one urban void area in the northern part of the 19th Middle School in Wuhan was selected as the case study area. This case was based on secondary data collection, field research, virtual 3D modelling and computer rendering. The aim was to achieve sustainable and synergistic economic, social and environmental development by activating urban void areas. The results found that the theoretical framework of sustainability had positive implications for operation and design. The scientific and practical value of the planning and design could be enhanced by fully considering the logic of sustainable operation. In addition, the innovative concepts of the sustainable framework provided a theoretical and practical basis for filling the research gap of interventions in the urban void area.
One Step Sol-Gel Synthesis and Morphostructural Characterization of Sodium Titanate Particles
Authors: Gheorghe Florina-Diana , Dumitrescu Cristina Rodica , Gheorghe Petrache-Ionuţ , Deák Habil György , Ting Sam Sung
Published: October 2023

Titanate-based materials are attractive inorganic adsorbents for wastewater treatment but also could be used as high performances ceramics. In this study, platelets and wires like morphologies of sodium titanate were successfully synthesized via an unconventional sol-gel method, starting with titanium tetrachloride, TiCl4 and sodium hydroxide, NaOH precursors, and coupled with hydrothermal maturation at 160°C for 24h. Afterwards, through an alkaline hydrothermal maturation, this intermediate phase gradually converted into a sodium titanate with a preserved morphology. The powder thus obtained, was compositionally characterized using X-Ray Diffraction (XRD) and Electron Dispersive Spectroscopy (EDS), structural properties were highlighted by imaging through Scanning Electron Microscopy (SEM) and Thermogravimetric measurements were carried out to determine the transformations that occur between 25-1000 °C. It is shown that a mix of two titanate phase Na2TinO2n+1 with n = 3 and 6 was obtained, having wires and platelet like morphology and micron sizes particles, with a crystallite size of 22 nm grown on Miller indices plane (200). This work was designed to improve the production yield by using an unconventional titanate synthesis method and precursors.
Influence of pretreated coconut shell on gasification product yield
Authors: Muda S.Z. , Ahmad R. , Mohammed S.A. , Wan Ahmad W.A.M. , Vijean V. , Santiagoo R. , Ibrahim N.R. , Ani A.Y.
Published: October 2023

Gasification of untreated and pretreated coconut shell (CS) was carried out in a fixed-bed reactor to assess the effect of temperature (600, 650, 700, 750, and 800 °C) and holding time (30 and 40 min) on gases composition. The untreated CS was first torrefied in a fixed-bed reactor at different temperatures (200 – 300 °C) and holding times (30 min, 60 min and 90 min). Pretreated CS at the optimal torrefaction temperature (275 °C and 60 min) was used for gasification. Under optimal conditions of 750 °C and 30 min holding time, gasification contributed the most gas production. At this optimum condition, the gas composition of pretreated CS was 35.03 % of CH4, 24.43 % of CO2, and 40.54 % of H2 + CO. Untreated CS contains 37.63 % of CH4, 24.03 % of CO2, and 38.34 % of H2 + CO gases. The production of CH4 gas was higher when untreated CS was used for gasification rather than pretreated CS. Moreover, when untreated CS was used for gasification, the amount of CO2, H2, and CO produced was minimal. Therefore, for high H2 production, pretreatment prior to gasification is appropriate.
Mass Transfer Coefficients in Hollow Fiber Dialyzers
Authors: Baker J. A. , Osburn J. O. , Lawton R. L.
Published: October 2023

A method for determination of mass transfer coefficients in hollow fiber membrane dialyzers is described. The procedure makes use of a hollow fiber dialysis cascade to obtain length concentration profiles experimentally. The mass transfer coefficients may be related to various mass transfer resistances.
Left Atrial Vent Device
Authors: Wiltfang Daniel H. , Doty Donald B.
Published: October 2023

A right angle sump catheter device for use in venting the left side of the heart through the left atrium during operations using cardiopulmonary bypass has been described. Design features were based upon aspiration of the most dependent portion of the left atrium. It has proven useful in rendering a dry operating field.

Aspiration of blood returning to the left side of the heart during cardiopulmonary bypass from bronchial or aorto-pulmonary collateral circulation is necessary in many open intracardiac operations. Traditionally, this blood has been removed through a catheter inserted through the apex of the left ventricle. This method has generally been satisfactory, but problems associated with catheter position in trabeculae of the left ventricle, control of suction, damage to the ventricular myocardium, and risk of hemorrhage have led to use of the left atrium as the venting site of choice in most instances. A vent catheter inserted into the left atrium offers major safety and convenience factors, as well as placing the aspiration catheter at the most dependent point in the heart. A right angle sump device has been designed and used in over 500 open intracardiac procedures. It has proven to be very effective and essentially problem free in removing blood from the left atrium.
Left Atrial Femoral Bypass Set-up for Descending Aortic Aneurysm Using the Cardiotomy Reservoir
Authors: Peterson Stephen
Published: October 2023

An oxygenator is not needed for bypass of the descending thoracic aorta from the left atrium to the femoral artery. This technique has been utilized on several occasions and found to be very satisfactory.
Arterial and Venous Aspirator
Authors: Peterson Stephen
Published: October 2023

It is important to remove all the bubbles from the perfusate before going on bypass. By using the hose end to Leur Lok connector on the end of one of the suction lines, the cannula and connector can be completely freed of air bubbles.

A cannula aspirator can be connected to the end of one of the suction lines of the heart-lung bypass set-up to aspirate air from the connector and cannula. This technique is faster than using a syringe, and the blood can be saved by putting it back into the system. (See Figure 2)
Core Needle Biopsy Accuracy for Androgen Receptor Expression in Invasive Breast Cancer
Authors: Santos Marcelle Morais dos , Frasson Antonio Luiz , Silva Vinicius Duval da , Maciel Aluísio de Castro Antunes , Watte Guilherme , Werutsky Gustavo , Reinert Tomás , Fay André Poisl
Published: October 2023

Objective Breast cancer (BC) biomarkers, such as hormone receptors expression, are crucial to guide therapy in BC patients. Antiandrogens have been studied in BC; however, limited data are available on androgen receptor (AR) expression test methodology. We aim to report the core needle biopsy (CNB) accuracy for AR expression in BC.

Methods Patients diagnosed with stage I-III invasive BC from a single institution were included. Androgen receptor expression was evaluated by immunohistochemistry (IHC) using 1 and 10% cutoff and the AR expression in surgical specimens (SS) was the gold standard. Kappa coefficients were used to evaluate the intraprocedural agreement.

Results A total of 72 patients were included, with a mean age of 61 years old and 84% were Luminal A or B tumors. The prevalence of AR expression in all BC samples was 87.5% using a cutoff ≥ 10% in SS. With a cutoff value ≥ 1%, CNB had an accuracy of 95.8% (Kappa value = 0.645; 95% confidence interval [CI]: 0.272–1.000; p < 0.001) and 86.1% (Kappa value = 0.365; 95% CI: 0.052–0.679; p < 0.001) when ≥ 10% cutoff was used for AR positivity. Androgen receptor expression in CNB (cutoff ≥ 1%) had a sensitivity of 98.5%, specificity of 60%, positive predictive value of 97.0%, and a negative predictive value of 76.9% in the detection of AR expression in SS.

Conclusion Core needle biopsy has good accuracy in evaluating AR expression in BC. The accuracy of CNB decreases with higher cutoff values for AR positivity.
Religious diversity education: raising children’s awareness of religious diversity through augmented reality
Authors: Li Xin-Zhu , Chen Chun-Ching , Kang Xin
Published: October 2023

Religious diversity education has become increasingly prominent in the last few years. As the region with the second-highest religious diversity globally, Chinese Taiwan provides its students religious education early on, thus minimising misunderstandings and discrimination on the basis of religion. To diversify teaching methods, educators have adopted interactive technology as one of the primary teaching aids. This study aims to develop and evaluate the impact of an interactive technology, augmented reality (AR) in the provision of religious education. A series of experiments were conducted during the 2020 Taipei Lantern Festival of Religious Education Exhibition to explore whether using the interactive technology system significantly improved learning outcomes in comparison to traditional learning methods. To this end, a total of 50 elementary students across two experimental (n = 24) and control (n = 26) groups were recruited to participate in the study. A mixed-methods approach was used to analyse students’ subjective and objective learning outcomes. The results of the study showed that the experimental group performed significantly better in both subjective and objective learning outcomes. The findings obtained from the open-ended questions showed interactive AR technology system use positively affected the learning process. In conclusion, this study proposes that combining religious diversity education with interactive AR technology has the potential to improve students’ motivation, engage their interest, improve learning outcomes, and contribute to an increased awareness of religious diversity. It may also be helpful in limiting students’ cognitive overload during the learning process.
Hamiltonian systems of Jordan block type: Delta-functional reductions of the kinetic equation for soliton gas
Authors: Vergallo P. , Ferapontov E. V.
Published: October 2023

We demonstrate that linear degeneracy is a necessary condition for quasilinear systems of Jordan block type to possess first-order Hamiltonian structures. Multi-Hamiltonian formulation of linearly degenerate systems governing delta-functional reductions of the kinetic equation for dense soliton gas is established (for KdV, sinh-Gordon, hard-rod, Lieb-Liniger, DNLS, and separable cases).
Shielded ionisation discharge (SID) probe for spatiotemporal profiling of pulsed molecular beam
Authors: Patel Milaan , Thomas Jinto , Chandra Joshi Hem
Published: October 2023

Intense pulsed supersonic molecular beams are used in many applications such as tokamak fueling, edge plasma diagnostics, ion beam profile monitors, laser cluster experiments, chemical kinetics, etc. Measurement of absolute density is required to optimize beam sources used in these experiments. Absolute density measurement of a continuous molecular beam is challenging due to its small size and rarefied flow, which makes it even more difficult for a pulsed molecular beam due to its transient nature. In this work, we demonstrate a novel probe to measure the spatiotemporal evolution of the absolute number density of a pulsed supersonic molecular beam. The probe is named the Shielded Ionization Discharge probe. It measures density using localized discharge within the molecular beam created by the thermionic emission of electrons from a hot filament. We describe the design, calibration, and characterization of the developed probe. The performance of the probe is demonstrated by measuring the spatial and temporal profiles of a pulsed supersonic molecular beam of 1.5 ms duration.
Composed solutions of synchronized patterns in multiplex networks of Kuramoto oscillators
Authors: Jain Priya B. , Nguyen Tung T. , Mináč Ján , Muller Lyle E. , Budzinski Roberto C.
Published: October 2023

Networks with different levels of interactions, including multilayer and multiplex networks, can display a rich diversity of dynamical behaviors and can be used to model and study a wide range of systems. Despite numerous efforts to investigate these networks, obtaining mathematical descriptions for the dynamics of multilayer and multiplex systems is still an open problem. Here, we combine ideas and concepts from linear algebra and graph theory with nonlinear dynamics to offer a novel approach to study multiplex networks of Kuramoto oscillators. Our approach allows us to study the dynamics of a large, multiplex network by decomposing it into two smaller systems: one representing the connection scheme within layers (intra-layer), and the other representing the connections between layers (inter-layer). Particularly, we use this approach to compose solutions for multiplex networks of Kuramoto oscillators. These solutions are given by a combination of solutions for the smaller systems given by the intra- and inter-layer systems, and in addition, our approach allows us to study the linear stability of these solutions.
The superharmonic instability and wave breaking in Whitham equations
Authors: Carter John D. , Francius Marc , Kharif Christian , Kalisch Henrik , Abid Malek
Published: October 2023

The Whitham equation is a model for the evolution of surface waves on shallow water that combines the unidirectional linear dispersion relation of the Euler equations with a weakly nonlinear approximation based on the Korteweg–De Vries equation. We show that large-amplitude, periodic, traveling-wave solutions to the Whitham equation and its higher-order generalization, the cubic Whitham equation, are unstable with respect to the superharmonic instability (i.e., a perturbation with the same period as the solution). The threshold between superharmonic stability and instability occurs at the maxima of the Hamiltonian and L2-norm. We examine the onset of wave breaking in traveling-wave solutions subject to the modulational and superharmonic instabilities. We present new instability results for the Euler equations in finite depth and compare them with the Whitham results. We show that the Whitham equation more accurately approximates the wave steepness threshold for the superharmonic instability of the Euler equations than does the cubic Whitham equation. However, the cubic Whitham equation more accurately approximates the wave steepness threshold for the modulational instability of the Euler equations than does the Whitham equation.
A liquid metal dropper for experiments on the wettability of liquid metals on plasma facing components
Authors: López Pérez C. , Marchhart T. , Kawashimo K. , Nieto-Perez M. , Parsons M. S. , Schamis H. , Allain J. P.
Published: October 2023

A liquid metal dropper has been developed as a part of the Ion-Gas-Neutral Interactions with Surfaces 2 (IGNIS-2) facility at The Pennsylvania State University. The dropper has the capability of directly applying drops to candidate plasma facing materials for nuclear fusion reactors to enable measurements of their liquid metal wetting properties. The results presented here are specific to the use of lithium in the dropper. This paper discusses the design choices of the liquid metal dropper and its chamber, including the heating and temperature control and the dropper’s motorized operation. Lithium drops of masses ranging from 0.05 g up to 0.13 g, equivalent to drop diameters between 5.6 mm to 1 cm, have been consistently dispensed by the dropper. A new algorithm is developed and used to automate the analysis of the contact angle between the liquid drops and substrate material for efficient analysis of video data recorded to study the wetting properties of candidate plasma-facing components.
Harvesting blue energy: pH-regulated nanochannels inspired by carbon nanostructures
Authors: Khatibi Mahdi , Mojavezi Amirhosein , Pourjafarabadi Esmaiel
Published: October 2023

Reverse electrodialysis (RED) in soft nanochannels has emerged as a promising approach for energy generation. In this study, we investigate energy production characteristics of RED in soft nanochannels and compare the performance of conical and cylindrical geometries. The significance of the concentration ratio and the influence of the charged polyelectrolyte layer (PEL) properties are examined to optimize energy conversion efficiency. The mathematical model includes Nernst–Planck–Poisson equations and creeping flow equation to describe ionic transport and fluid flow within the nanochannel. The conical and cylindrical geometries of the nanochannel are considered, and the soft layer is modeled as pH-dependent, allowing for unique interfacial interactions. Our results demonstrate that both conical and cylindrical nanochannels exhibit increasing osmotic flows and diffusion potentials with the concentration ratio. However, the cation transfer number decreases with the concentration ratio due to reduced selectivity in higher concentrations. Maximum power generation increases with increasing concentration ratio in both geometries. Remarkably, conical nanochannels consistently outperform cylindrical nanochannels in terms of energy production efficiency. The maximum energy conversion efficiency exhibits a decreasing trend with the concentration ratio, highlighting the importance of utilizing small concentration ratios for economical operation. Additionally, denser PELs with distinct properties from the electrolyte yield higher efficiency levels across a wide range of concentration ratios. Our comprehensive study provides valuable insight into the energy production characteristics of RED in soft nanochannels, emphasizing the superior performance of conical geometries. These findings contribute to advance nanoscale-based energy conversion technologies for sustainable energy production.
Effect of dimple edge ratio on the thermo-aerodynamic performance in turbulent channel flow
Authors: Nasr M. A. , Tay C. M. , Khoo B. C.
Published: October 2023

In the past few decades, dimples have shown their great capability of enhancing heat transfer along with promising potentials for reducing hydraulic losses and improving the overall thermo-aerodynamic efficiency of turbulent channel flows. In an effort to further optimize the dimple design, this study focuses on the effect of the dimple edge ratio (ER), defined as the ratio between the dimple rounded-edge and base sphere radii, on the channel thermo-aerodynamic performance for ER=0.5, 1, 2, 4, 5, and 10 at two different Reynolds numbers, Reτ ≅180 and 590. For this purpose, the wall-resolved large eddy simulation was used to simulate the flow over the dimples arranged in a staggered form and fitted only on the bottom wall of the channel. Reduction in the required pumping power was observed with increasing the dimple edge ratio up to 4.5% at ER=10 for Reτ ≅180 and around 4% for Reτ ≅590. The thermo-aerodynamic performance of the cases under the study shows an increase in total drag of the dimpled wall for all the cases but accompanied by heat transfer enhancement. The thermo-aerodynamic efficiency was represented in the form of area (Ga) and volume (Gv) goodness factors, where Ga showed almost asymptotic improvement between 1.5% and 2.3% and Gv was observed to have the highest improvement for the benchmark ER value of 0.5 for both Reynolds numbers of 6.8% and 5.8% at Reτ ≅180 and 590, respectively, then reduces with increasing the edge ratio. Overall, all the dimple designs included in this study show improvement in terms of heat transfer performance and thermo-aerodynamic efficiency.
On paradoxical phenomena during evaporation and condensation between two parallel plates
Authors: Chen Gang
Published: October 2023

Kinetic theory has long predicted that temperature inversion may happen in the vapor-phase for evaporation and condensation between two parallel plates, i.e., the vapor temperature at the condensation interface is higher than that at the evaporation interface. However, past studies have neglected transport in the liquid phases, which usually determine the evaporation and condensation rates. This disconnect has limited the acceptance of the kinetic theory in practical heat transfer models. In this paper, we combine interfacial conditions for mass and heat fluxes with continuum descriptions in the bulk regions of the vapor and the liquid phases to obtain a complete picture for the classical problem of evaporation and condensation between two parallel plates. The criterion for temperature inversion is rederived analytically. We also prove that the temperature jump at each interface is in the same direction as externally applied temperature difference, i.e., liquid surface is at a higher temperature than its adjacent vapor on the evaporating interface and at a lower temperature than its adjacent vapor on the condensing interface. We explain the interfacial temperature jump and temperature inversion using the interfacial cooling and heating processes, and we predict that this process can lead to a vapor phase temperature much lower than the lowest wall temperatures and much higher than the highest wall temperature imposed. When the latent heat of evaporation is small, we found that evaporation can happen at the low temperature side while condensation occurs at the high temperature side, opposing the temperature gradient.
Whispering gallery mode HgCdTe laser operating near 4 μm under Peltier cooling
Authors: Razova A. A. , Fadeev M. A. , Rumyantsev V. V. , Utochkin V. V. , Dubinov A. A. , Aleshkin V. Ya. , Mikhailov N. N. , Dvoretsky S. A. , Gusev N. S. , Shengurov D. V. , Morozova E. E. , Gavrilenko V. I. , Morozov S. V.
Published: October 2023

Due to their widely tunable bandgap, HgCdTe heterostructures with quantum wells are a promising material system for semiconductor lasers in the entire mid-infrared range. Recently, Auger-suppressed structures allowed interband stimulated emission (SE) in the atmospheric transparency window 3–5 μm well above 200 K, while previously it was limited to temperatures below 175 K. In contrast to earlier works focused on ridge or vertical emitting HgCdTe lasers, here we demonstrate a whispering gallery mode microdisk (d = 50 μm) laser operating under optical pumping at ∼4 μm in the temperature range attainable by the thermoelectric cooling. Above 200 K, the emission spectrum consists of multiple 0.37-meV-wide peaks associated with the modes of the disk resonator. Laser generation is achieved up to 230 K, which is 40 K lower than the quenching temperature of SE in the unprocessed macroscopic sample. We associate the difference with the optical losses introduced by the inclined walls of the disk.
Evaluation of algebraic models of anomalous transport in a multi-fluid Hall thruster code
Authors: Marks Thomas A. , Jorns Benjamin A.
Published: October 2023

The behavior of four algebraic closure models for anomalous electron transport is investigated using a fluid Hall thruster code. The models, which were selected because they have been previously described in the literature, are calibrated against a baseline experimental condition of a 9-kW-class magnetically shielded Hall thruster operating at 300 V and 15 A on xenon propellant. The extensibility of the models is then assessed by using this calibrated model to simulate three additional operating conditions—300 V and 30 A, 600 V and 15 A, and 300 V and 15 A operating on krypton propellant. The quality of the model prediction is quantified by comparing the model outputs to experimental measurements of discharge current, thrust, and ion velocity. It is found that while none of the models can predict the ion acceleration characteristics accurately, some compare favorably in terms of the scaling of thrust and discharge current across operating conditions. The limitations of the models are attributed to the coupling between the functional scaling of the closure models with respect to the local plasma properties and the fluid model. The role of the electron energy balance in this coupling is also highlighted. These results are discussed in the context of motivating improved closure models of the anomalous electron transport in Hall thrusters.
Phase behaviour of semiflexible lattice polymers in poor-solvent solution: Mean-field theory and Monte Carlo simulations
Authors: Marcato Davide , Giacometti Achille , Maritan Amos , Rosa Angelo
Published: October 2023

We study a solution of interacting semiflexible polymers with curvature energy in poor-solvent conditions on the d-dimensional cubic lattice using mean-field theory and Monte Carlo computer simulations. Building upon past studies on a single chain, we construct a field-theory representation of the system and solve it within a mean-field approximation supported by Monte Carlo simulations in d = 3. A gas-liquid transition is found in the temperature-density plane that is then interpreted in terms of real systems. Interestingly, we find this transition to be independent of the bending rigidity. Past classical Flory–Huggins and Flory mean-field results are shown to be particular cases of this more general framework. Perspectives in terms of guiding experimental results towards optimal conditions are also proposed.
Numerical study of flow characteristics around a 30° yawed circular cylinder at Re=104
Authors: Wang Ran , Cheng Shaohong , Ting David S.-K.
Published: October 2023

Unstable motions of bridge stay cables have been observed on site and in wind tunnel tests when a cable is yawed at certain orientations to wind. To uncover the underlying mechanisms, flow around a circular cylinder at a yaw angle of 30° has been numerically analyzed in the current study using delayed detached eddy simulation (DDES) at Re=104. A comparison with the reference normal flow case indicates the presence of a more coherent span-wise flow structure when the cylinder is yawed at 30°. The application of proper orthogonal decomposition further reveals that at this orientation, a synchronized flow structure exists, which is characterized by continuous anti-symmetric pressure blocks. In addition, a low-frequency flow fluctuation has been identified, the Strouhal number of which is roughly a quarter of that of the conventional Kármán vortex shedding. The pivotal role of axial flow in the intermittent amplification of cylinder sectional lift and the subsequent span-wise propagation of this enhanced local lift event has been revealed. The former is evident from the low-frequency sectional lift peaks occurred during vortex shedding, whereas the propagation speed associated with the latter is in good agreement with the span-wise component of the incoming flow speed. The temporal and spatial impact of axial flow on the surrounding flow structure of the cylinder may serve as a periodic excitation source, which could trigger an unstable response of a cylinder. This, in the context of bridge stay cables, could possibly contribute to the onset mechanism of dry cable galloping.
Blood component separation in straight microfluidic channels
Authors: Lee Lap Man , Bhatt Ketan H. , Haithcock Dustin W. , Prabhakarpandian Balabhaskar
Published: October 2023

Separation of blood components is required in many diagnostic applications and blood processes. In laboratories, blood is usually fractionated by manual operation involving a bulk centrifugation equipment, which significantly increases logistic burden. Blood sample processing in the field and resource-limited settings cannot be readily implemented without the use of microfluidic technology. In this study, we developed a small footprint, rapid, and passive microfluidic channel device that relied on margination and inertial focusing effects for blood component separation. No blood dilution, lysis, or labeling step was needed as to preserve sample integrity. One main innovation of this work was the insertion of fluidic restrictors at outlet ports to divert the separation interface into designated outlet channels. Thus, separation efficiency was significantly improved in comparison to previous works. We demonstrated different operation modes ranging from platelet or plasma extraction from human whole blood to platelet concentration from platelet-rich plasma through the manipulation of outlet port fluidic resistance. Using straight microfluidic channels with a high aspect ratio rectangular cross section, we demonstrated 95.4% platelet purity extracted from human whole blood. In plasma extraction, 99.9% RBC removal rate was achieved. We also demonstrated 2.6× concentration of platelet-rich plasma solution to produce platelet concentrate. The extraction efficiency and throughput rate are scalable with continuous and clog-free recirculation operation, in contrast to other blood fractionation approaches using filtration membranes or affinity-based purification methods. Our microfluidic blood separation method is highly tunable and versatile, and easy to be integrated into multi-step blood processing and advanced sample preparation workflows.
Making good on the promise of genomics in healthcare: the NSW Health perspective
Authors: Willcox Deb , Trent Ronald J. A. , Lyons Nigel , Meldrum Cliff , Kennedy Peter , Lee Tamara , Berman Yemima , Burgess Bronwyn , Cannings John William , Canova Martin Joseph , Halliburton Celia , Hibbitt Olivia , Norris Sarah Karen , Penna Antonio , Perkins Andrew , Pilowsky Eva , Rushton Shelley
Published: October 2023

NSW Health is implementing genomics as a mainstream component of clinical care. The strategic, holistic approach is considering infrastructure, data governance and management, workforce, education, service planning and delivery. This work is generating insights about how to realise the promise of genomics in healthcare, highlighting the need for strong foundations, real-world application, accessibility and a focus on people using genomic information in clinical care.