bluuebunny/crossref_metadata_2025 huggingface dataset:
The hypnagogic state: A brief update
Authors: Ghibellini Romain , Meier Beat
Published: August 2022

The hypnagogic state refers to a transitional stage between wakefulness and sleep, in which sensory perceptions can be experienced. In this review, we compile and discuss the recent scientific literature on hypnagogia research regarding the future directions proposed by Schacter (1976; Psychological Bulletin, 83, 452). After a short introduction discussing the terminology used in hypnagogia research and the differentiation of hypnagogic states with other related phenomena, we review the reported prevalence of hypnagogic states. Then, we evaluate the six future directions suggested by Schacter and we propose three further future directions. First, a better understanding of the emotional quality of hypnagogic states is needed. Second, a better understanding of why hypnagogic states occur so frequently in the visual and kinaesthetic modalities is needed. Lastly, a better understanding of the purpose of hypnagogic states is needed. In conclusion, research has made great progress in recent years, and we are one step closer to demystifying the hypnagogic state.
Extracted tissue‐specific atelocollagens have distinctive textural properties
Authors: Nakamura Sayaka , Hoshi Hiroko , Wakabayashi Kaito , Seki Manami , Watanabe Makoto , Watanabe Momoka , Inaba Hiroki , Ushijima Natsumi , Akasaka Tsukasa
Published: August 2022

Food texture is a very important factor for elderly persons, children, and patients who have difficulty swallowing. Collagen and its hydrolysis product, gelatin, are used as ingredients in foods, dietary supplements, and medical materials. In this study, we extracted atelocollagen from nonedible porcine tissues, including ear, nose, and skin, and analyzed the biophysical properties of each tissue. Extracted whole auricle collagen (AEC) showed superior springiness, while only the skin region of auricle collagen (ASC) showed superior hardness, springiness, and brittleness. Body skin collagen showed high hardness but low springiness. In a shear stress test, ASC gels showed high shear strength, and their strains coincided with hardness in a textural examination, while nose and AEC showed low maximum strains. In viscosity, the auricular collagens showed higher viscosity regardless of the region of the ear. Fibril formation in collagen from each tissue and organ varied a great deal in width and morphology. We found that the same type of collagen had a unique texture and viscosity under physiological conditions depending on the tissue or organ of extraction. The results show that the collagen extracted from each organ has a unique texture and unique possibilities to serve as an ingredient in food or supplements.
Natural history, spectrum and outcome of stage 3 AKI in patients with acute‐on‐chronic liver failure
Authors: Maiwall Rakhi , Rastogi Archana , Pasupuleti Samba Siva R. , Hidam Ashini K. , Singh Mansi , Kadyan Sonia , Jain Priyanka , Kumar Guresh , Sarin Shiv K.
Published: August 2022

Background and Aim

There is limited data on natural course and interventions in stage‐3 acute kidney injury (AKI‐3) in patients with acute‐on‐chronic liver failure (ACLF). We studied the factors of AKI‐3 reversal and outcomes of dialysis in ACLF patients.

Methods

Consecutive patients with ACLF were prospectively enrolled (n = 1022) and variables determining AKI and its outcomes were analysed.

Results

At 1 month, 337 (33%) patients had AKI‐3, of which, 131 had AKI‐3 at enrolment and 206 developed AKI‐3 during hospital stay. Of patients with AKI‐3 at enrolment, 18% showed terlipressin response, 21% had AKI resolution and 59% required dialysis. High MELD (≥35) (model 1), serum bilirubin (≥23 mg/dL) (model 2) and AARC score (≥11) (model 3) were independent risk factors for dialysis. Dialysis was associated with worse survival in all AKI patients but improved outcomes in patients with AKI‐3 (p = .022, HR 0.69 [0.50–0.95]). Post‐mortem kidney biopsies (n = 61) revealed cholemic nephropathy (CN) in 54%, acute tubular necrosis (ATN) in 31%, and a combination (CN and ATN) in 15%. Serum bilirubin was significantly higher in patients with CN, CN and ATN compared with ATN respectively ([30.8 ± 12.2] vs. [26.7 ± 12.0] vs. [18.5 ± 9.8]; p = .002).

Conclusion

AKI‐3 rapidly increases from 13% to 33% within 30 days in ACLF patients. Histopathological data suggested cholemic nephropathy as the predominant cause which correlated with high bilirubin levels. AKI‐3 resolves in only one in five patients. Patients with AARC grade 3 and MELD >35 demand need for early dialysis in AKI‐3 for improved outcomes.
Position‐track‐time three‐dimensional network model‐based improvement for high‐speed rail scheduling and operation
Authors: Wang Jin , Ai Chengbo , Chen Yongjun , A Runa , Wang Weidong , Qiu Shi
Published: August 2022

The train timetable and station operation plan play a critical role in the high‐speed railway (HSR) planning and management. The existing hierarchical optimization methods for the planning process of the HSR would affect the efficiency of train schedules and are often difficult to achieve an optimized scheme. This paper proposes a position‐track‐time three‐dimensional network, which describes the process of train operations in sections and stations at a macroscopic scale, while the track infrastructure including the position of insulation joints in stations are modeled microscopically. The modeled train running times and dwell times are based on standard timetable design values given in full minutes by the China Railway Corporation, while the interlocking times and minimum headway times are not specified explicitly. The problem is formulated as a large‐scale 0–1 linear integer programming model, which is solved using an extended branch‐and‐price algorithm. The effectiveness and precision of the model are verified through a real‐world case study on the Beijing–Shanghai HSR line. The results indicate that the proposed model can effectively improve the line capacity by 17.2% while ensuring that there is no conflict between train operations in sections and stations.
Feedback regulation of auxin signaling through the transcription of H2A.Z and deposition of H2A.Z to SMALL AUXIN UP RNAs in Arabidopsis
Authors: Sun Aiqing , Yin Chunmei , Ma Min , Zhou Ying , Zheng Xiaoyun , Tu Xiaoyu , Fang Yuda
Published: August 2022

Auxin is a critical phytohormone that is involved in the regulation of most plant growth and developmental responses. In particular, epigenetic mechanisms, like histone modifications and DNA methylation, were reported to affect auxin biosynthesis and transport. However, the involvement of other epigenetic factors, such as histone variant H2A.Z, in the auxin‐related developmental regulation remains unclear.

We report that the histone variant H2A.Z knockdown mutant in Arabidopsis Col‐0 ecotype, h2a.z‐kd, has more lateral roots and weak gravitational responses related to auxin‐regulated growth performances. Further study revealed that auxin promotes the eviction of H2A.Z from the auxin‐responsive genes SMALL AUXIN‐UP RNAs (SAURs) to activate their transcriptions.

We found that IAA promotes the transcription of H2A.Z genes through HOMEOBOX PROTEIN 22/25 (AtHB22/25) transcription factors which work as downstream targets of ARF7/19 in auxin signaling. Double mutant of hb22 hb25 showed similar lateral root and gravitropism phenotypes to h2a.z‐kd.

Our results shed light on a reciprocal regulation hub through INOSITOL AUXOTROPHY 80‐mediated H2A.Z eviction and ARF7/19‐HB22/25‐mediated H2A.Z transcription to modulate the activation of SAURs and plant growth in Arabidopsis.
Information theory and plant ecology
Authors: Jessup Laura H. , Halloway Abdel H. , Mickelbart Michael V. , McNickle Gordon G.
Published: August 2022

To survive, all organisms must sense and respond to information from their environment. This is true of many organisms, including plants, which need to do all the things that other organisms do while operating under the limitations of being sessile and lacking a central nervous system. In this article, we explore how information theory can apply to plants and briefly review the types and sources of information and the mechanisms that plants use to perceive and respond to their environment. We identify and describe three primary modes by which a plant receives information: chemical, electromagnetic and mechanical. We describe how plants integrate information to detect the state of their neighbors, capture resources and regulate growth and metabolism. Overall, we find that plants interpret information from their surroundings as an emergent property of distributed information processed by a network of cells. We end with a prospectus of directions for future research including decoding signal from noise, storage of information, additional means of information transmission and two‐way information signaling with biotic partners.
Mortality and Related Risk Factors of Fragile Hip Fracture
Authors: Wang Pei‐Wen , Yao Xue‐Dong , Zhuang Hua‐Feng , Li Yi‐Zhong , Xu Hao , Lin Jin‐Kuang , Liu Wen‐Ge
Published: August 2022

Objective

To explore the mortality of patients with fragile hip fractures and assess the death‐associated risk factors.

Methods

A total of 690 patients with osteoporotic hip fractures (age, 50–103 years) that were treated from January 2010 to December 2015 were enrolled and followed‐up in this study and the clinical data were retrospectively collected. Three months, 1 year, and the total mortality were measured. Mortality‐related risk factors were assessed including age, gender, surgery, the duration from injury to operation, pulmonary infection, and the number and type of complications. The mortality of each group was compared by chi‐square test or corrected chi‐square test for univariate analysis, and the factors with statistically significant mortality difference confirmed by univariate analysis were analyzed by binary logistic multivariate analysis.

Results

The 3‐month mortality was 7.69%, the 1‐year mortality was 15.60%, and the total mortality of the follow‐up time was 24.06%. The 1‐year and total mortality during the follow‐up of the patients were higher in the >75‐year‐old group than those in the ≤75‐year‐old group (p = 0.000, respectively); were higher in the male patients than that in the female patients (p = 0.042; p = 0.017, respectively); were significantly lower in the operation group than that in the non‐operation group (p = 0.000, respectively); were significantly lower in the patients that underwent the operation in ≤5 days than the patients that underwent the operation within >5 days (p = 0.008; p = 0.000, respectively); were significantly lower in patients with >2 kinds of combined medical diseases than those with ≥2 kinds of chronic diseases (p = 0.000, respectively); were significantly lower in patients receiving anti‐osteoporosis treatment than in patients not receiving anti‐osteoporosis treatment (p = 0.000, p = 0.002, respectively). Binary logistic regression analysis showed that the independent risk factors affecting mortality included advanced age >75‐years‐old (OR = 5.653, p = 0.000), male (OR = 1.998, p = 0.001), non‐surgical treatment (OR = 9.909, p = 0.000), the number of combined medical diseases ≥2 (OR = 1.522, p = 0.042), and non‐anti‐osteoporosis treatment (OR = 1.796, p = 0.002).

Conclusion

Age, whether or not surgical treatment was performed, the number of medical diseases, and whether or not anti‐osteoporosis treatment was performed were independent risk factors for 3‐month and 1‐year mortality in patients with fragile hip fractures.
Planetary‐scale change to the biosphere signalled by global species translocations can be used to identify the Anthropocene
Authors: Williams Mark , Leinfelder Reinhold , Barnosky Anthony D. , Head Martin J. , McCarthy Francine M. G. , Cearreta Alejandro , Himson Stephen , Holmes Rachael , Waters Colin N. , Zalasiewicz Jan , Turner Simon , McGann Mary , Hadly Elizabeth A. , Stegner M. Allison , Pilkington Paul Michael , Kaiser Jérôme , Berrio Juan Carlos , Wilkinson Ian P. , Zinke Jens , Delong Kristine L.
Published: August 2022

We examine three distinctive biostratigraphic signatures of humans associated with hunting and gathering, landscape domestication and globalization. All three signatures have significant fossil records of regional importance that can be correlated inter‐regionally and help describe the developing pattern of human expansion and appropriation of resources. While none have individual first or last appearances that provide a globally isochronous marker, all three signatures overlap stratigraphically, in that they are part of a continuum of change, with complex regional patterns. Here we show that during the later stages of globalization, late nineteenth to twentieth century records of species translocations can be used to build an interconnected web of palaeontological correlation with decadal or sub‐decadal precision that dovetails with other stratigraphic markers for the Anthropocene. This palaeontological web is also a proxy for accelerating species extinction and of a state shift in the biosphere in the twentieth century.
Extensive blaschkoid hypopigmentation in a girl with MED12‐related disorder
Authors: Wang Cynthia X. , King Katherine B. , Bayliss Susan J.
Published: August 2022

MED12‐related disorders represent a spectrum of rare neurodevelopmental disorders causing intellectual disability, dysmorphic features, and other systemic abnormalities. We report a case of a 21‐month‐old girl with extensive hypopigmentation following Blaschko lines attributed to underlying MED12‐related disorder.
Reassessment of the occurrence and distribution of Xanthomonas arboricola on fruit trees in Iran
Authors: Zarei Sadegh , Taghavi S. Mohsen , Osdaghi Ebrahim
Published: August 2022

Bacterial canker and spot of stone fruits and bacterial blight of walnut, caused by different pathovars of Xanthomonas arboricola, namely X. arboricola pv. pruni and X. arboricola pv. juglandis, respectively, are considered among quarantine or regulated (nonquarantine) agents in different countries. The two pathogens were initially reported in Iran in 2005 and 1977, respectively. However, the precise identity, pathogenicity status and geographic distribution of these pathogens have been questioned. In this study, we have employed a series of comprehensive field surveys and samplings over a course of 5 years (2015–2019) across 16 provinces to reassess and clarify the occurrence and distribution of X. arboricola on fruit and nut trees in Iran. Besides dozens of non‐Xanthomonas and nonpathogenic bacterial strains, 27 X. arboricola strains were isolated from stone fruits (n = 13) and walnut (n = 14). Except for the strains Peh35, Peh78 and Peh79, the stone fruit strains were nonpathogenic on their host of isolation as well as several other plant species, while the walnut strains were pathogenic on their host of isolation. Multilocus sequence analysis (MLSA) of four housekeeping genes, atpD, dnaK, gyrB and rpoD, revealed that among the stone fruit strains only Peh78 and Peh79 could be assigned into X. arboricola pv. pruni, while the walnut strains were identified as X. arboricola pv. juglandis. Based on the results of pathogenicity assays and phylogenetic analyses, we confirm the occurrence of X. arboricola pv. juglandis in Iran, while X. arboricola pv. pruni was absent in the plant samples evaluated in this study.
Changes in sperm metabolites of Dezhou donkey after cryopreservation
Authors: Yu Jie , Wang Zhaofei , Wang Fuwen , Wang Wenhao , Ge Shihao , Fan Zhaobin , Liu Bing , Li Min , Dong Boying , Zhao Fuwei , Dang Ruihua
Published: August 2022

Sperm cryopreservation technology has laid the foundation for promoting the popularity of artificial insemination in donkey reproduction, but the freeze–thaw process can cause sperm damage, and the viability of frozen sperm is greatly reduced, resulting in low insemination ability. Sperm metabolites play an important role in the freezing process of spermatozoa and have a major influence on the freezability of spermatozoa. The aim of this study was to explore the differential metabolites in donkey spermatozoa before and after cryopreservation by liquid chromatography–tandem mass spectrometry (LC–MS/MS). We analysed ejaculate samples from male donkeys obtained before and after freezing and identified 1323 metabolites. Compared with fresh sperm (F), the metabolites of cryopreserved sperm (CRY) were significantly changed, and 570 metabolites were significantly different between the two groups (p < .05). Among them, 277 metabolites were higher in frozen sperm, while the opposite was true for 293 metabolites. These metabolites mainly include phospholipids, lysophospholipids and amino acids., most of which are associated with oxidative stress and sperm capacitation. We describe significantly different metabolites before and after freezing that are significantly associated with decreased sperm motility post‐freezing and can be used as biomarkers of decreased sperm motility post‐freezing.
Interprofessional collaboration utilizing oral health therapists in nursing homes: Perceptions of oral health therapists and nursing home staff in Singapore
Authors: Ho Shenna Yu‐En , Walsh Laurence James , Pradhan Archana , Yang Jingrong , Chan Pei Yuan , Lopez Silva Claudia Patricia
Published: August 2022

Introduction

Oral health therapists (OHTs) have the potential to increase the access to oral care for elderly residents in nursing homes (NHs).

Aims

To evaluate the perceptions of NH staff and OHTs regarding the barriers and enablers toward oral care provision for elderly NH residents, and their perceptions toward interprofessional collaboration through the utilization of OHTs in NHs.

Methodology

Electronic surveys were completed by 231 direct care and 15 managerial staff from 15 NHs, and 103 OHTs. Factors influencing oral care provision, and aspects of awareness, capabilities, and willingness/interest toward collaboration were evaluated.

Results

The OHTs and NH staff reported mutually positive responses toward interprofessional collaboration. The most frequently reported barriers by the NH staff were the lack of regular support from dental health professionals and inadequate knowledge and skills. The OHTs expressed willingness and competence in assisting the NH staff, but lacked regulatory and educational support.

Conclusion

OHTs have the potential to address the barriers faced by the NH staff, if adequately supported through policy and education. Oral health promotion in intermediate and long‐term care sectors should take into account this potential for interprofessional collaboration through greater utilization of the skill‐set of OHTs.
Perceptions of interprofessional education among Malaysian clinical healthcare students
Authors: Ahmad Mas Suryalis , Asban Muhammad Asyrani , Mohd Salleh Nur Syafiah Aina , Mohd Sarmin Nurul ‘Izzah , Abd Rahman Aida Nur Ashikin
Published: August 2022

Introduction

Interprofessional education (IPE), which is aimed at improving the quality of patient care and overall health outcome, has been advocated to prepare future healthcare professionals for collaborative practice

Objectives

This study aimed to investigate the perceptions of IPE among clinical healthcare students at a Malaysian institution

Methods

A validated questionnaire, developed from previous studies, was distributed online to selected final year students of 10 clinical programs from medical, dental, pharmacy and health sciences faculties (n = 501). Quantitative data was analyzed via chi‐square test (significance value p < .05) using social sciences software (SPSS).

Results

The overall response rate was 76.4% (n = 383). About 63.2% of respondents reported having experienced IPE. This experience took place in lectures (32.1%) and online courses/webinars (36.2%). The majority of respondents provided positive feedback on various aspects of IPE. There was an insignificant difference among respondents across all programs in terms of their perception of its importance and effectiveness as well as their own preference for multidisciplinary lectures as a mode to conduct IPE. Most students agreed that challenges in conducting IPE include time constraints (83%), communication difficulties (70.8%), and lack of skills (57.4%), with no significant difference across programs. Students opined that IPE was beneficial in providing exposure to other disciplines, encouraging peer interactions, developing new skills, and improving overall learning experience. However, some reported challenges in integrating with other students, while others cited compromised experience due to problems with crowd control

Conclusion

Students’ support for IPE has positive implications for future implementation and highlights areas for improvement and further development.
Justice for Walker: Warlpiri responses to the police shooting of Kumunjayi Walker
Authors: Hargraves Ned Jampijinpa , Fernandez‐Brown Samara , Nelson Harry Jakamarra , Granites Robin Japanangka , Robertson Eddie Jampijinpa , Martin Valerie Napaljarri , Brown Margaret Napanangka , Williams Warren Japanangka , Williams Louanna Napangardi , Curran Georgia
Published: August 2022

The police shooting of Kumunjayi Walker in Yuendumu in November 2019 instigated an immediate and determined response from Warlpiri families who were shocked and saddened by the death of a loved one in the prime of his life and enraged by this latest event in a long string of colonial injustices. This article collates perspectives as expressed in interviews and public statements from Warlpiri spokespeople who have been on the frontline of the fight for Justice for Walker. Incorporating the initial responses in the days after the shooting, the links to the Coniston massacre in Warlpiri and neighbouring country in 1928, the ongoing horror of Aboriginal deaths in custody and the escalating energy behind the Black Lives Matter campaigns across the world, this article illustrates, through Warlpiri voices, the ways in which people from Yuendumu have expertly used the techniques of activist campaigns in their resolute fight for justice for Walker, for all Aboriginal people across Australia and for Black and First Nations people world‐wide.
LESSONS FROM THE QUEST FOR ARTIFICIAL CONSCIOUSNESS: THE EMERGENCE CRITERION, INSIGHT‐ORIENTED AI, AND IMAGO DEI
Authors: Lumbreras Sara
Published: August 2022

There are several lessons that can already be drawn from the current research programs on strong AI and building conscious machines, even if they arguably have not produced fruits yet. The first one is that functionalist approaches to consciousness do not account for the key importance of subjective experience and can be easily confounded by the way in which algorithms work and succeed. Authenticity and emergence are key concepts that can be useful in discerning valid approaches versus invalid ones and can clarify instances where algorithms are considered conscious, such as Sophia or LaMDA. Subjectivity and embeddedness become key notions that should also lead us to re‐examine the ethics of decision delegation. In addition, the focus on subjective experience shifts what is relevant in our understanding of ourselves as human beings and as an image of God, namely, in de‐emphasizing intellectuality in favor of experience and contemplation over action.
Design, Development, and Validation of a Whole-Body Vibration Measurement Device
Authors: Silva Patrícia , Seabra Eurico , Mendes Joaquim
Published: August 2022

Measurements of whole-body vibration are fundamental to access and evaluate comfort levels and possible injury development in the human being. International standards such as ISO 2631 and ISO 10326 are dedicated to the measurement and validation of mechanical systems to access vibration levels. Nowadays, the traditional measurement devices require multiple components and so hence become highly bulky, do not allow autonomous data recording, and are expensive. Following the previously mentioned standards, the present research is focused on the design and validation of a new and economic whole-body vibration measurement device. The developed device, besides being capable to measure the whole-body vibration, allows the user to select multiple sample ratings, is capable to record data on a µSD card, is easily moved and adapted, and is autonomous and low cost. This device is composed of three main components: a tri-axial accelerometer, a protective metal case, and semi-rigid rubber disc. Shaker tests were conducted to evaluate the measurement capability of the whole system and the influence of each component on the vibration measurements. This article will introduce the design and development steps for the proposed system. Concerning the validation phase, its results will be discussed and analyzed.
Optimization of an Organic Ranking Cycle Radial Turbine Using a Reduced-Order Model Coupled With Computational Fluid Dynamics
Authors: Alvarez-Regueiro Eva , Yang Bijie , Barrera-Medrano Esperanza , Martinez-Botas Ricardo , Rajoo Srithar
Published: August 2022

This paper presents the geometry optimization of a single stage radial turbine for an organic ranking cycle (ORC) system operating over a pressure ratio of 9. The specific fluid used in this investigation is R1233zd (E), but the methodology applies to other organic fluids as well. The ORC system is used to recover excess waste heat from the operation of an offshore oil and gas platform in the gulf of Thailand and its conditions will be replicated at pilot plant level. The geometry is optimized for the highest total-to-static efficiency using nongradient based algorithms to allow for wide design space. Firstly, a one-dimensional meanline geometry is optimized, which is followed by a computational fluid dynamics (cfd) optimization in three-dimensional using a parameterized model. cfd is used to validate and calibrate the meanline model as well as to understand the flow and the sensitivity of the design parameters not captured by the low-order model. Moreover, the flow field of the successful designs is analyzed by cfd to identify the main flow structures that explain the difference in performance among the designs. The nonideal gas thermophysical properties of R1233zd (E) are calculated using equations of state to account for the nonideal gas behavior.
Experimental Investigation of Interactions Between Two Closely Spaced Azimuthal Modes in a Multinozzle Can Combustor
Authors: Kim Jeongwon , John Tony , Adhikari Subodh , Wu David , Emerson Benjamin , Acharya Vishal , Isono Mitsunori , Saito Toshihiko , Lieuwen Timothy
Published: August 2022

Thermoacoustic instabilities in annular or circular combustors are often coupled with azimuthal modes. These modes can be characterized by a spin ratio (SR), which quantifies the dominant mode between two counter-rotating waves, and a phase difference between them, which is directly related to the orientation of the antinodal line. This study investigates the instability amplitudes, SR, and phase difference of two closely spaced (3% of their mean frequency), yet distinct azimuthal modes; one is the first azimuthal (1A) mode, and the other is a combination of first azimuthal and first longitudinal (1A1L) mode. Each mode itself consists of two peaks that are spaced even more closely in frequency (0.8%). Furthermore, distinct harmonics at 2× and 3× of these frequencies, presumably associated with nonlinearities, are also evident in the spectra. Each mode is bandpass filtered in spectrum to analyze them separately. For the 1A mode, the SR and phase difference exhibit a variety of behaviors—including quasi-periodic standing waves, spinning waves, and intermittency—depending on operating conditions such as thermal power and azimuthal fuel staging. Similar trends are observed for the 1A1 L mode. Moreover, there is clear coupling between the 1A and 1A1 L modes, as their SRs are almost synchronized during the quasi-periodic standing wave. This synchronization is observed in phase differences as well, but not in the instability amplitude. For spinning dominant wave conditions, the SRs of each mode have similar average values, but they fluctuate in a seemingly random fashion. For the phase difference, both average and fluctuation are not correlated. In contrast, the instability amplitudes are strongly correlated, with modulation of the 1A mode leading to that of the 1A1 L mode. These results clearly indicate that complex coupling occurs across closely spaced frequencies under instability conditions, coupling that must be understood in order to capture limit cycle dynamics.
Computational and Experimental Assessment of a MW-Scale Supercritical CO2 Compressor Operating in Multiple Near-Critical Conditions
Authors: Toni Lorenzo , Bellobuono Ernani Fulvio , Valente Roberto , Romei Alessandro , Gaetani Paolo , Persico Giacomo
Published: August 2022

This work illustrates the results of a wide experimental campaign in the frame of the EU-funded project sCO2-Flex, which focused on the investigation of a MW-scale sCO2 compressor operating in plant-representative conditions. The experimental tests were carried out for four temperature levels between 304.15 K and 309.15 K at a fixed pressure of 79.79 bar, hence covering an extended thermodynamic region close to the critical point. The experimental results are thoroughly discussed with the support of steady computational fluid-dynamics simulations, assuming homogeneous flows and thermodynamic equilibrium for the two-phase flow description. Changing the upstream total state, two peculiar variabilities in the compressor pressure ratio and choking flow rate are experimentally and computationally observed. While the former is mainly related to the single-phase flow thermodynamics, the latter originates from the onset of two-phase flows. As the simulations predict the experimental choking with a maximum error of 3%, the corresponding two-phase speed of sound is analyzed to infer the underlying equilibria between phases. It is found that, for the tested conditions, two-phase flows quickly achieve thermodynamic equilibrium, and non-equilibrium or metastable effects arguably play a marginal role in the process.
Reduced Order Modeling of Forced Response in a Multistage Compressor Under Mistuning and Aerocoupling
Authors: Maroldt Niklas , Schwerdt Lukas , Berger Ricarda , Panning-von Scheidt Lars , Rolfes Raimund , Wallaschek Jörg , Seume Joerg R.
Published: August 2022

Vibration amplitudes and fatigue life in multistage turbomachinery are commonly estimated by an investigation of the individual stages. Research is currently extending the scope to include structural and aeroelastic interstage coupling. Both effects have been shown to significantly influence blade vibrations. For safe operation of modern blisk blading with its lower structural damping due to the elimination of frictional contacts at the blade roots, an accurate prediction of the vibration behavior with mistuning is necessary to avoid high cycle fatigue failures. In this paper, a cyclic Craig-Bampton reduction method with a priori interface reduction for multistage rotors is extended to handle aeroelastic effects. This reduced order model efficiently predicts forced response in multistage applications. Aeroelastic multistage simulations are carried out using the harmonic balance method to account for the stage interactions and yield damping and stiffness coefficients, as well as excitation forces. Small structural mistuning is projected onto the tuned system modes of the rotor. The approach is applied to a 2.5-stage compressor configuration. Monte Carlo simulations show the sensitivity of vibration amplitudes to the aeroelastic coupling for mistuning. The aeroelastic interstage coupling is found to originate mainly from acoustic mode propagation between the stages. The fatigue of rotor blades is significantly affected by multistage interactions since vibration amplitudes increase due to the superposition of the responses of multiple modes. This leads to the conclusion that aeroelastic multistage effects need to be incorporated in future design procedures to allow for an accurate prediction of fatigue life.
Measuring Atmospheric Radon Levels Using a Cloud Chamber
Authors: Geske Matthew , Murray-Weston Crystal , Lelack Graham
Published: August 2022

The Wilson cloud chamber, invented in 1911 by Scottish physicist Charles Wilson, is a remarkably simple and effective charged particle detector. Cloud chambers were used regularly in particle physics experiments for decades, until being supplanted by bubble chambers. In this article, we describe a lab activity that is suitable for introductory-level physics students using a cloud chamber to measure the rate of alpha decay in the atmosphere. In performing this experiment, the students deepen their understanding of alpha decay, including the random nature of the process. They also become acquainted with statistical uncertainties from measuring a random process.
The Physics of Electric Cars
Authors: Nalence Eugene Edward
Published: August 2022

The Edison Institute predicts that there will be at least 19 × 106 all-electric vehicles (EVs) in use by 2030. This will produce significant effects on our transportation system and its energy requirements. Investigating these effects is an ideal activity to show the relevance of physics. How efficient are EVs in using energy? What demand will they place on the already-stressed electric power grid? What are issues related to the batteries used? The growth in EV usage takes place in the context of the perceived need to reduce CO2 emissions to mitigate climate change and global warming. This article will only consider EVs, but relevant and reasonable background information about climate change issues (in my opinion) can be found in physicist Steven E. Koonin’s controversial book Unsettled: What Climate Science Tells Us, What It Doesn’t, and Why It Matters. To ensure fuller consideration of other perspectives, one should also read reviews of Koonin’s work.
Piezoelectric shear rheometry: Further developments in experimental implementation and data extraction
Authors: Mikkelsen Mathias , Eliasen Kira L. , Lindemann Niclas , Moch Kevin , Böhmer Roland , Karimi-Varzaneh Hossein Ali , Lacayo-Pineda Jorge , Jakobsen Bo , Niss Kristine , Christensen Tage , Hecksher Tina
Published: August 2022

The piezoelectric shear gauge (PSG) [Christensen and Olsen, Rev. Sci. Instrum. 66, 5019 (1995)] is a rheometric technique developed to measure the complex shear modulus of viscous liquids near their glass transition temperature. We report recent advances to the PSG technique: (1) The data extraction procedure is optimized, which extends the upper limit of the frequency range of the method to between 50 and 70 kHz. (2) The measuring cell is simplified to use only one piezoelectric ceramic disk instead of three. We present an implementation of this design intended for liquid samples. Data obtained with this design revealed that a soft extra spacer is necessary to allow for thermal contraction of the sample in the axial direction. Model calculations show that flow in the radial direction is hindered by the confined geometry of the cell when the liquid becomes viscous upon cooling. The method is especially well-suited for—but not limited to—glassy materials.
Mental Health Symptoms of Amateur Association Football Referees: A Cross-Sectional Study
Authors: Lima Yavuz , Devran Sergen , Webb Tom , Bayraktar Bülent
Published: August 2022

Although referees who officiate in the amateur football leagues are exposed to various stressors that can negatively affect their mental health (MH), little is known about their MH symptoms. The purpose of the study was to evaluate MH symptoms of referees who officiate in the Turkish amateur football leagues. An online survey was sent to all referees in the Turkish amateur football leagues (n = 4,900) incorporating standardized scales assessing depression, anxiety, and stress. A total of 1,279 referees participated in the study. Female referees reported higher depression (p < .01) and anxiety (p = .02) scores than males. Younger referees (23–27 years) reported higher depression (p = .01) and anxiety (p < .01) scores than older (>38 years) referees. Results showed that symptoms of depression, anxiety, and stress scores were associated with marital status (being single), lower incomes, severe sports injury history, and inadequate social support. In light of these results, MH assessments should be undertaken to detect which referees are at greater risk of MH problems and facilitate appropriate and timely MH interventions. Further study is needed to inform MH risk reduction strategies and/or programming.
Lin28a induces SOX9 and chondrocyte reprogramming via HMGA2 and blunts cartilage loss in mice
Authors: Jouan Yohan , Bouchemla Zohra , Bardèche-Trystram Benoit , Sana Joanna , Andrique Caroline , Ea Hang-Korng , Richette Pascal , Latourte Augustin , Cohen-Solal Martine , Hay Eric
Published: August 2022

Articular cartilage has low regenerative capacity despite permanent stress. Irreversible cartilage lesions characterize osteoarthritis (OA); this is not followed by tissue repair. Lin28a, an RNA binding protein, is detected in damaged cartilage in humans and mice. We investigated the role of LIN28a in cartilage physiology and in osteoarthritis. Lin28a-inducible conditional cartilage deletion up-regulated
Mmp13
in intact mice and exacerbated the cartilage destruction in OA mice. Lin28a-specific cartilage overexpression protected mice against cartilage breakdown, stimulated chondrocyte proliferation and the expression of Prg4 and Sox9, and down-regulated
Mmp13
. Lin28a overexpression inhibited Let-7b and Let-7c miRNA levels while RNA-sequencing analysis revealed five genes of transcriptional factors regulated by Let-7. Moreover, Lin28a overexpression up-regulated HMGA2 and activated SOX9 transcription, a factor required for chondrocyte reprogramming. HMGA2 siRNA knockdown inhibited the cartilage protective effect of Lin28a overexpression. This study provides insights into a new pathway including the Lin28a-Let7 axis, thus promoting chondrocyte anabolism in injured cartilage in mice.
Spin Hall effect of transversely spinning light
Authors: Peng Liang , Ren Hang , Liu Ya-Chao , Lan Tian-Wei , Xu Kui-Wen , Ye De-Xin , Sun Hong-Bo , Xu Su , Chen Hong-Sheng , Zhang Shuang
Published: August 2022

Light carries spin angular momentum, which, in the free space, is aligned to the direction of propagation and leads to intriguing spin Hall phenomena at an interface. Recently, it was shown that a transverse-spin (T-spin) state could exist for surface waves at an interface or for bulk waves inside a judiciously engineered metamaterial, with the spin oriented perpendicular to the propagation direction. Here, we demonstrate the spin Hall effect for transversely spinning light—a T-spin–induced beam shift at the interface of a metamaterial. It is found that the beam shift takes place in the plane of incidence, in contrast to the well-known Imbert-Fedorov shifts. The observed T-spin–induced beam shift is of geometrodynamical nature, which can be rendered positive or negative controlled by the orientation of T-spin of the photons. The unconventional spin Hall effect of light found here provides a previously unexplored mechanism for manipulating light-matter interactions at interfaces.
Cancer-driving mutations are enriched in genic regions intolerant to germline variation
Authors: Vitsios Dimitrios , Dhindsa Ryan S. , Matelska Dorota , Mitchell Jonathan , Zou Xuequing , Armenia Joshua , Hu Fengyuan , Wang Quanli , Sidders Ben , Harper Andrew R. , Petrovski Slavé
Published: August 2022

Large reference datasets of protein-coding variation in human populations have allowed us to determine which genes and genic subregions are intolerant to germline genetic variation. There is also a growing number of genes implicated in severe Mendelian diseases that overlap with genes implicated in cancer. We hypothesized that cancer-driving mutations might be enriched in genic subregions that are depleted of germline variation relative to somatic variation. We introduce a new metric, OncMTR (oncology missense tolerance ratio), which uses 125,748 exomes in the Genome Aggregation Database (gnomAD) to identify these genic subregions. We demonstrate that OncMTR can significantly predict driver mutations implicated in hematologic malignancies. Divergent OncMTR regions were enriched for cancer-relevant protein domains, and overlaying OncMTR scores on protein structures identified functionally important protein residues. Last, we performed a rare variant, gene-based collapsing analysis on an independent set of 394,694 exomes from the UK Biobank and find that OncMTR markedly improves genetic signals for hematologic malignancies.
Regulation of PD-L1 through direct binding of cholesterol to CRAC motifs
Authors: Wang Qian , Cao Yunlei , Shen Lijuan , Xiao Taoran , Cao Ruiyu , Wei Shukun , Tang Meng , Du Lingyu , Wu Hongyi , Wu Bin , Yu Yang , Wang Shuqing , Wen Maorong , OuYang Bo
Published: August 2022

Cholesterol, an essential molecule for cell structure, function, and viability, plays crucial roles in the development, progression, and survival of cancer cells. Earlier studies have shown that cholesterol-lowering drugs can inhibit the high expression of programmed-death ligand 1 (PD-L1) that contributes to immunoevasion in cancer cells. However, the regulatory mechanism of cell surface PD-L1 abundance by cholesterol is still controversial. Here, using nuclear magnetic resonance and biochemical techniques, we demonstrated that cholesterol can directly bind to the transmembrane domain of PD-L1 through two cholesterol-recognition amino acid consensus (CRAC) motifs, forming a sandwich-like architecture and stabilizing PD-L1 to prevent downstream degradation. Mutations at key binding residues prohibit PD-L1–cholesterol interactions, decreasing the cellular abundance of PD-L1. Our results reveal a unique regulatory mechanism that controls the stability of PD-L1 in cancer cells, providing an alternative method to overcome PD-L1–mediated immunoevasion in cancers.
Thermo-mechanical volume change behavior of municipal solid waste: experimental study and constitutive model
Authors: Li Yu Ping , Chen Jia Rui , Shi Jianyong , Li Xiulei , Wu Xun
Published: August 2022

This paper investigates the thermo-mechanical volume change behavior of municipal solid waste (MSW) by conducting drained heating–cooling tests at constant stresses and isothermal consolidation tests using a temperature-controlled triaxial apparatus. The experimental results show that the compression and swelling indexes of MSW specimen were temperature independent, and the heating-induced volumetric contraction was partially reversible upon cooling. Different from conventional soils, the thermally induced reversible and irreversible volumetric strains of MSW were much larger and stress level dependent. Apart from the experimental study, an isotropic thermo-elastoplastic constitutive model was developed in the framework of existing modified Cam-clay model, which allows the prediction of thermally induced volume changes of MSW. An important feature in this model was the derivation of thermally induced plastic volumetric strain based on the concept of equivalent stress. The capability of the proposed model was validated against the experimental results and showed good predictions. This paper serves as the first attempt to study the thermo-mechanical volume change behavior of MSW, and has provided additional data for the serviceability evaluation of existing pipes as well as settlement and capacity estimation of MSW landfills at elevated temperatures.
Dynamics of nanoparticle diameter and interfacial layer on flow of non-Newtonian (Jeffrey) nanofluid over a convective curved stretching sheet
Authors: Gowda R. J. Punith , Kumar R. Naveen , Khan Umair , Prasannakumara B. C. , Zaib Aurang , Ishak Anuar , Galal Ahmed M.
Published: August 2022

This study inspects the steady flow of a Jeffrey nanofluid stimulated by the linear stretching of a curved sheet. Working fluid is made up of graphene nanoparticles in a base medium of water. The heat sink/ source and convective boundary condition phenomenon highlights the heat transfer of the flow. The effect of liquid–solid interfacial layer and the nanoparticle diameter is also presented at the molecular level to illustrate the thermal integrity of the considered flow. Leading equations are numerically assessed after being transformed into dimensionless forms by using similarity transformations. To enhance the analysis part, several graphs and tables are shown. The features of a wide range of parameters are explored and discussed. The impact of these parameters on the rate of heat transport is also explored. Results reveal that the nanofluid velocity increases for curvature parameter. In addition, the heat transmission amplifies for heat source parameter and convective parameter. The rate of heat transport amplifies for curvature parameter and Biot number but deteriorates for heat source/ sink parameter.
Natural vibration analysis of an embedded elastic metamaterial beam based on effective medium theory and Rayleigh–Ritz method
Authors: Shu Haisheng
Published: August 2022

Elastic metamaterial (EM) beam is a kind of special composite structure with peculiar dynamic properties that are beneficial for relevant vibration isolating applications. The vibration properties and proper analysis methods of these special structures are the main concerns in practical designs and analyses. Existing analytic methods can only be applied to a few cases with simple geometric shapes and boundary conditions, hence more general analysis means are needed to be developed. In this paper, a general analysis method is proposed by combining the effective medium theory (EMT) and Rayleigh–Ritz method. Based on the method, the natural vibration properties of a typical EM beam are revealed clearly and correctly, such as absence of natural frequencies within bandgap, gathering of natural frequencies in the vicinity of band edges and particular modal correspondence before and behind bandgap. The effectiveness of the proposed method is validated by the analysis results, thus providing a feasible way for analyzing many complex cases where EM beams are included.
A new generalized KdV equation: Its lump-type, complexiton and soliton solutions
Authors: Hosseini K. , Salahshour S. , Baleanu D. , Mirzazadeh M. , Dehingia K.
Published: August 2022

A new generalized KdV equation, describing the motions of long waves in shallow water under the gravity field, is considered in this paper. By adopting a series of well-organized methods, the Bäcklund transformation, the bilinear form and diverse wave structures of the governing model are formally extracted. The exact solutions listed in this paper are categorized as lump-type, complexiton, and soliton solutions. To exhibit the physical mechanism of the obtained solutions, several graphical illustrations are given for particular choices of the involved parameters. As a direct consequence, diverse wave structures given in this paper enrich the studies on the KdV-type equations.
Turing instability in the fractional-order system with random network
Authors: Zheng Qianqian , Shen Jianwei , Zhao Yanmin , Zhou Lingli , Guan Linan
Published: August 2022

The epidemic often spreads along social networks and shows the effect of memorability on the outbreak. But the dynamic mechanism remains to be illustrated in the fractional-order epidemic system with a network. In this paper, Turing instability induced by the network and the memorability of the epidemic are investigated in a fractional-order epidemic model. A method is proposed to analyze the stability of the fractional-order model with a network through the Laplace transform. Meanwhile, the conditions of Turing instability and Hopf bifurcation are obtained to discuss the role of fractional order in the pattern selection and the Hopf bifurcation point. These results prove the fractional-order epidemic model may describe dynamical behavior more accurately than the integer epidemic model, which provides the bridge between Turing instability and the outbreak of infectious diseases. Also, the early warning area is discussed, which can be treated as a controlled area to avoid the spread of infectious diseases. Finally, the numerical simulation of the fractional-order system verifies the academic results is qualitatively consistent with the instances of COVID-19.