bluuebunny/crossref_metadata_2025 huggingface dataset:
The circadian clock sets a spatial–temporal window for recent thymic emigrants
Authors: Minaduola Mili , Aili Abudureyimujiang , Bao Yuhui , Peng Zhi , Ge Qing , Jin Rong
Published: August 2022

The diurnal timing system regulates multiple functions of lymphocytes in peripheral lymphoid organs. Whether T‐cell development in the thymus and T‐cell egress from the thymus are affected by the circadian clock is not clear. Herein, we used flow cytometry to examine the cell number and percentage of total thymocytes and various thymocyte subsets from Zeitgeber time (ZT) 1 to ZT21. CD4 and CD8 single‐positive (SP) thymocytes, in particular, the mature CD4 SP4 thymocyte subset with emigration capability and P‐phycoerythrin+ CD4 SP thymocytes in the perivascular space of the thymus, exhibited robust circadian oscillations. The diurnal expression of sphingosine‐1‐phosphate receptor‐1 (S1PR1) and CCR2 on SP thymocytes and the rhythmic sphingosine‐1‐phosphate (S1P) and CCL2 gradient formed between peripheral blood and thymus likely promoted SP thymocyte egress in a circadian pattern. Switching the daylight cycle disturbed the rhythm of S1PR1 and CCR2 expression and subsequent thymocyte output. We further demonstrated that the core clock molecule BMAL1 had rhythmic binding of the promoters of Klf2, S1pr1 and Sphk2. Together, we elucidated the circadian dynamic characteristics of mature thymocyte egress, which coordinated with the diurnal changes in T‐cell homing to the lymph nodes. The core rhythmic molecule BMAL1 likely promoted thymocyte emigration through transcriptional regulation of emigration‐related molecules.
Evolution of a metastable thin film with high‐hardness wear resistance for advanced cutting tool application
Authors: Kim Myungjae , Kim Jiwoo , Seo Minkyeong , Kim Jiwoong
Published: August 2022

The structure and elastic properties of rocksalt and wurtzite Ti–Al–N ternary solid solutions were investigated using first principles calculations. We also performed an experimental evaluation using the sputtering method to obtain the reliability. The phase transition of (Ti1−xAlx)N solid solutions was occurred at x = 0.5–0.75 for both calculations and experimental results. The bulk modulus of rocksalt and wurtzite solid solutions decreases with increasing Al content. On the other hand, shear moduli and Young's moduli gradually increase with Al content only in rocksalt solid solutions. The theoretical and experimental results indicate that the overall mechanical properties of rocksalt solid solutions are superior to those of wurtzite solid solutions. Therefore, controlling the crystal structure of the Ti–Al–N ternary metastable system was crucial for optimizing the material properties.
Microstructural design of textured KSr2Nb5O15 ceramics by a phase‐field simulation and lamination technique
Authors: Zhang Yongmei , Liu Liangliang , Jiang Xinyu , Hou Zhaoping
Published: August 2022

The densification of textured ceramics requires a small template size. However, it is challenging to complete the directional arrangement into the matrix by small templates during the templated grain growth. We propose a strategy to increase the density and texture degree of KSr2Nb5O15 ceramics. The microstructures can be designed by a phase‐field simulation and lamination technique. For the textured KSr2Nb5O15 ceramics, a high piezoelectricity of d33 = 98 pC/N (the highest reported d33 is 65 pC/N) is achieved by the microstructural control. This study provides a novel technique for preparation of textured piezoelectric ceramics with high performances.
Investigating the behaviour of Atlantic salmon (Salmo salar L.) post‐smolts during their early marine migration through the Clyde Marine Region
Authors: Lilly Jessie , Honkanen Hannele M. , Bailey David M. , Bean Colin W. , Forrester Ruaidhri , Rodger Jessica R. , Adams Colin E.
Published: August 2022

It is thought that survival during migration is particularly poor for Atlantic salmon post‐smolts immediately after entry into sea and particularly in the estuarine environment. Nonetheless, there is currently a lack of information on Atlantic salmon post‐smolt movement behaviour in estuaries in the UK. This study used acoustic tagging to estimate loss rates and compare the behaviour of Atlantic salmon post‐smolts migrating from two distinctly different rivers draining into the Clyde Estuary, the River Endrick (n = 145) and the Gryffe (n = 102). Contrary to most literature, post‐smolts undertook rapid migrations through the estuary, potentially decreasing their exposure to predators/anthropogenic stressors and reducing their estimated loss rates (river: 1%–3% km–1; estuary: 0.20%–0.60% km–1). The low loss rates in the estuary occurred despite post‐smolts engaging in passive reversal movements with the tide upon entering the estuary, possibly allowing them more time to adapt to the increased salinity. Atlantic salmon post‐smolts from both the rivers used similar migration pathways exiting into the coastal marine zone during ebbing tide. This study provides novel information on the timing and migratory routes of Atlantic salmon post‐smolts in the Clyde Estuary that can ultimately be used to inform management decisions on how to assess and reduce the potential impacts of current natural and anthropogenic stressors. Temporal repeatability of this study over multiple years is required to determine if there is variation in the factors driving the migratory patterns and loss rates of smolts in this system.
Economic policy uncertainty and insider trading
Authors: El Ghoul Sadok , Guedhami Omrane , Nash Robert , Wang He (Helen)
Published: August 2022

In this article, we examine the effects of economic policy uncertainty (EPU) on insider trading. Two hypotheses predict that EPU is positively related to insider trading volume and profitability: (1) the private benefits hypothesis, which states that insiders exploit their information advantage to realize abnormal profits, and (2) the signaling hypothesis, which states that insiders trade to signal private information to stock market participants. We find that EPU is positively and significantly related to the profitability of insider purchases, and that insiders purchase more frequently during high‐EPU periods. Additional analysis provides strong support for the signaling hypothesis but no support for the private benefits hypothesis.
A mixed‐methods analysis of telehealth implementation in nursing homes amidst the COVID‐19 pandemic
Authors: Powell Kimberly R. , Winkler Amy E. , Liu Jianfang , Alexander Gregory L.
Published: August 2022

Background

The COVID‐19 pandemic has forced nursing homes to adapt new models of care in response to the evolving crisis including rapid implementation of telehealth services. The purpose of our study was to investigate implementation of telehealth in nursing homes amidst the COVID‐19 pandemic using a human factors model.

Methods

Using a mixed methods design, we conducted a secondary analysis of data from a national survey of nursing home administrative leaders (n = 204). Using six survey questions, we calculated a total telehealth score (range 0–42). Descriptive statistics and paired sample t‐test were used to explore the change in telehealth in two consecutive years (2019–2021). Next, we conducted semi‐structured interviews with (n = 21) administrators and clinicians to assess differences in implementation according to extent of telehealth use.

Results

The mean telehealth score in year 1 was 12.11 (SD = 9.85) and year 2 was 19.25 (SD = 11.25). There was a significant difference in telehealth scores from year 1 to year 2 (t = 6.83, p < 0.000). While 64% of nursing homes reported higher telehealth scores in year 2 compared to year 1, over 32% reported a decline. Qualitative analysis revealed facilitators of telehealth including training, use of integrated equipment, having staff present for the visit, and using telehealth for different types of visits. Barriers included using smart phones to conduct the visit, billing, interoperability and staffing.

Conclusion

Training, adaptation of work processes to support communication, and restructuring teams and tasks are the result of interactions between system components that could improve usability and sustainability of telehealth in nursing homes.
Long‐term evolutionary adaptation of SIVcpz toward HIV‐1 using a humanized mouse model
Authors: Schmitt Kimberly , Curlin James , Remling‐Mulder Leila , Morrison Jared , Moriarty Ryan , Goff Kelly , Stenglein Mark , O'Connor Shelby , Marx Preston , Akkina Ramesh
Published: August 2022

Critical genetic adaptations needed for SIV chimpanzee to evolve into HIV‐1 are not well understood. Using humanized mice, we mimicked the evolution of SIVcpzLB715 into HIV‐1 Group M over the course of four generations. Higher initial viral load, increased CD4+ T‐cell decline, and nonsynonymous substitutions arose suggesting viral evolution.
Ligularia fischeri ethanol extract: An inhibitor of alpha‐melanocyte‐stimulating hormone‐stimulated melanogenesis in B16F10 melanoma cells
Authors: Joo In‐Hwan , Choi Ji‐Hee , Kim Dong‐Hee , Chung Moon‐Jung , Lim Mi‐Hye
Published: August 2022

Background

Ligularia fischeri is a perennial herb isolated from plants of the Asteraceae family. Ligularia fischeri is distributed throughout Korea, Japan, eastern Siberia, and China.

Aims

The aim of this study is to examine the intracellular inhibitory effect of Ligularia fischeri ethanol extract on melanin synthesis and expression of tyrosinase and tyrosinase‐related protein 1 and 2. In addition, we analyzed the mitogen‐activated protein kinase signaling pathway and microphthalmia‐associated transcription factor in alpha‐melanocyte‐stimulating hormone‐stimulated B16F10 melanoma cells.

Methods

To assess the inhibition of melanogenesis in alpha‐melanocyte‐stimulating hormone‐stimulated B16F10 melanoma cells, the expression of melanogenesis‐related genes was investigated by quantitative real‐time polymerase chain reaction, while western blotting was performed to determine protein expression levels.

Results

We confirmed that the ethanol extract of Ligularia fischeri inhibited melanin synthesis in vitro by decreasing tyrosinase and tyrosinase‐related protein 1 and 2 expression. Furthermore, we revealed that tyrosinase expression was regulated by the suppression of microphthalmia‐associated transcription factor expression and activation of extracellular signal‐regulated kinase phosphorylation. The ethanol extract of Ligularia fischeri inhibited melanogenesis by activating extracellular signal‐regulated kinase phosphorylation and suppressing microphthalmia‐associated transcription factor and tyrosinase expression.

Conclusions

Ligularia fischeri ethanol extract may be used as an effective skin whitening agent in functional cosmetics.
Modeling dynamic personality theories in a continuous‐time framework: An illustration
Authors: Hecht Martin , Horstmann Kai T. , Arnold Manuel , Sherman Ryne A. , Voelkle Manuel C.
Published: August 2022

Objective

Personality psychology has traditionally focused on stable between‐person differences. Yet, recent theoretical developments and empirical insights have led to a new conceptualization of personality as a dynamic system (e.g., Cybernetic Big Five Theory). Such dynamic systems comprise several components that need to be conceptually distinguished and mapped to a statistical model for estimation.

Method

In the current work, we illustrate how common components from these new dynamic personality theories may be implemented in a continuous time‐modeling framework.

Results

As an empirical example, we reanalyze experience sampling data with N = 180 persons (with on average T = 40 [SD = 8] measurement occasions) to investigate four different effects between momentary happiness, momentary extraverted behavior, and the perception of a situation as social: (1) between‐person effects, (2) contemporaneous effects, (3) autoregressive effects, and (4) cross‐lagged effects.

Conclusion

We highlight that these four effects must not necessarily point in the same direction, which is in line with assumptions from dynamic personality theories.
Addressing stigma among persons living with HIV through the Sujaag project in Pakistan: A socioecological analysis
Authors: Khurshid Kainat , Dutta Tapati , Khan Kausar S. , Haider Syed Aun , Ahmed Usman Ali , Jatoi Hashmat , Tahir Mohammad , Sarfraz Raja , Pasha Aneeta , Khan Myra , Ali Mehek
Published: August 2022

HIV‐related stigma causes multifaceted problems for people with lived experiences. Stigma leads to feelings of shame and disgrace, and marginalizes persons living with HIV and their caregivers by marring social relationships and impacting health outcomes. In April 2019 Ratodero Tehsil in Larkana District, Pakistan, had an HIV outbreak, where evidence highlighted increase in infection rates among non‐high‐risk populations, including children. In the aftermath of this outbreak, affected families faced loss of communal ties in part due to stigmatizing attitudes. The Sujaag Project employed Participatory Action Research strategies to address HIV‐based stigma and enhance acceptance of people living with HIV in the region. By utilizing a qualitative methodology, this study reports manifestations in changes in HIV stigma at four layers of the Socioecological Model: Individual, Interpersonal, Community and Social, and Macro levels. Findings from focus group discussions and reflective narrative reports gathered at varied points of the project cycle create an understanding of how HIV‐related stigma affects wellbeing and how a collaborative and participatory approach aids in re‐establishment of social relationships. This study informs contextual methodologies for incorporating lived experiences of HIV in program design, service delivery, and policy influence, and can be adapted for other stigmatized illnesses in similar contexts.
Impact of current Australian paid parental leave on families of preterm and sick infants
Authors: Eeles Abbey L , Olsen Joy E , Cameron Kate L , McKinnon Clare T , Rawnsley Kate L , Cruz Melinda , Pussell Kylie , Dubois Kara , Hunt Rod W , Cheong Jeanie LY , Spittle Alicia J
Published: August 2022

Aim

Parents of preterm or sick infants are at increased risk of mental health problems. The financial stress associated with an infant's prolonged hospital stay can have an additional negative effect on families' wellbeing and child development. This study explores parent use of Australian paid parental leave (PPL) and the financial impact of having an infant requiring neonatal care.

Methods

Retrospective, cross‐sectional, online survey study conducted from November 2020 to February 2021. Participants were parents of babies born from 1 January 2013, admitted to a neonatal intensive care unit or special care nursery in Australia. The survey explored use of Australian Government and private sector PPL, and financial stress. Parent‐reported anxiety and depression were measured using the EuroQol Group 5D‐5L Anxiety and Stress Subscale.

Results

Two hundred and thirty‐one parents responded of which 93% had a preterm infant. Seventy‐three percent of infants were hospitalised for more than 1 month, and 34% were readmitted to hospital within the first year following discharge home. Eighty‐three percent of parents reported moderate, severe or extreme levels of anxiety or depression. Seventy‐six percent reported that having a child in hospital had a moderate‐very large financial impact on their family. Parents identified main costs to be travel, food, inability to work and direct medical costs.

Conclusions

Having an infant born preterm or sick has significant emotional and financial implications for families. The current Australian Government PPL scheme does not adequately support parents of preterm or sick infants, and a change is urgently needed to improve outcomes for this vulnerable population.
Holding Hope: Co‐producing eating disorders education that integrates the lived experience voice to inform best practice
Authors: Brand Gabrielle , Wise Steve , Calvert Shannon
Published: August 2022

Accessible Summary

What is known on the subject?

Eating Disorder (ED) education is predominating taught through a DSM‐V diagnostic criteria and clinically focused lens devoid of lived experience expertise.

What the paper adds to existing knowledge?

Current clinically focused ED education may be shaping health professional misunderstandings of EDs, influencing the therapeutic relationships between health professional and consumer which is key to the recovery process.

Integrating the lived experience voice through co‐produced, humanities‐based ED education deepens understandings and honours the complexities of EDs by bringing a much‐needed, alternate perspective to health professional learning, practice and research.

What are the implications for mental health nursing?

Reframing mental health education towards a more strengths‐based, trauma‐informed and recovery focused lens has the potential to upskill the health workforce in how to hold hope, space and learn to walk the fight with people living and recovering with an ED.
Playing Board Games to Learn Rational Numbers: AProof‐of‐Concept
Authors: Navarrete‐Ulloa Jairo A. , Munoz‐Rubke Felipe
Published: August 2022

Educational board games are a promising teaching method due to their low cost, playful, exploratory, and engaging nature. By drawing on analogical research, we created a game whose structure of spatial relationships mirrored the structure of rational numbers. We expected that children playing this game would improve their knowledge of fractions. We conducted a school intervention with an active control group and pretest‐posttest assessments to evaluate our board game. Playing this game promoted the learning of fractions, even after controlling for nonverbal cognitive abilities. This low‐cost educational game might help reduce the knowledge gap that separates less and more affluent children.
Effects of Preoperative Oral Electrolyte‐Carbohydrate Nutrition Supplement on Postoperative Outcomes in Elderly Patients Receiving Total Knee Arthroplasty: A Prospective Randomized Controlled Trial
Authors: He Yue , Tang Xiumei , Ning Ning , Chen Jiali , Li Peifang , Kang Pengde
Published: August 2022

Objective

Patients undergoing total knee arthroplasty (TKA) were primarily geriatric, with high risk of postoperative electrolyte disorders and malnutrition. Randomized controlled trials regarding oral nutrition supplement (ONS) strategies in TKA was sparse. This study aimed to evaluate the efficacy of preoperative oral electrolyte‐carbohydrate nutrition supplement (OECNS) on patients (aged >65 years) undergoing TKA.

Methods

From April 2019 to January 2020, 94 patients undergoing primary elective unilateral TKA in our hospital were considered in this prospective randomized controlled study. This study included patients aged over 65 years with ASA I‐III, and excluded patients with electrolyte disorders, malnutrition, and comorbidities. The control group (control group) received meal nutrition supplements (preoperative 6 h [Pre 6h]) and water (Pre 2h), while OECNS group (intervention group) received meal nutrition supplements (Pre 6h) and OECNS (Pre 2). The Student's t test and χ2 test was used. The primary outcomes were the patient‐reported comfort indicators (PRCIs) including hunger, thirst, nausea, vomiting, weakness, pain, anxiety, and general comfort. The secondary outcomes included indicators of electrolyte, nutrition, functional scores, clinical results, and complications.

Results

The scores of preoperative hunger (0.43 ± 0.10), pain (2.30 ± 0.34), and anxiety (9.04 ± 2.71) were significantly lower in OECNS group compared with control group (hunger, 1.19 ± 0.21; pain, 3.79 ± 0.26; anxiety, 11.21 ± 3.02) (Pre 1h) (all p < 0.05) as well as the weakness score on the first postoperative day (POD1) (OECNS group 3.57 ± 0.24; control group 5.15 ± 0.29; p < 0.001). A higher level of Na + (OECNS group 140.54 ± 3.39; control group 138.07 ± 5.21; p = 0.008) and a reduced rate of hyponatremia (OECNS group 6.4%; control group 21.3%; p = 0.036) on POD1 were found. Moreover, the higher level of blood glucose (Post 2h) and reduced rates of abnormal blood glucose (Pre 2h, Post 6h) were verified in control group (all p < 0.05). There was no significant difference regarding the other outcomes.

Conclusion

The administration of OECNS significantly improved subjective comfort, electrolytes, and blood glucose without increasing the rates of complications in patients (aged over 65 years) undergoing TKA.
Increasing temperature and vapour pressure deficit lead to hydraulic damages in the absence of soil drought
Authors: Schönbeck Leonie C. , Schuler Philipp , Lehmann Marco M. , Mas Eugénie , Mekarni Laura , Pivovaroff Alexandria L. , Turberg Pascal , Grossiord Charlotte
Published: August 2022

Temperature (T) and vapour pressure deficit (VPD) are important drivers of plant hydraulic conductivity, growth, mortality, and ecosystem productivity, independently of soil water availability. Our goal was to disentangle the effects of T and VPD on plant hydraulic responses. Young trees of Fagus sylvatica L., Quercus pubescens Willd. and Quercus ilex L. were exposed to a cross‐combination of a T and VPD manipulation under unlimited soil water availability. Stem hydraulic conductivity and leaf‐level hydraulic traits (e.g., gas exchange and osmotic adjustment) were tracked over a full growing season. Significant loss of xylem conductive area (PLA) was found in F. sylvatica and Q. pubescens due to rising VPD and T, but not in Q. ilex. Increasing T aggravated the effects of high VPD in F. sylvatica only. PLA was driven by maximum hydraulic conductivity and minimum leaf conductance, suggesting that high transpiration and water loss after stomatal closure contributed to plant hydraulic stress. This study shows for the first time that rising VPD and T lead to losses of stem conductivity even when soil water is not limiting, highlighting their rising importance in plant mortality mechanisms in the future.
Associations of neural error‐processing with symptoms and traits in a dimensional sample recruited across the obsessive–compulsive spectrum
Authors: Riesel Anja , Härpfer Kai , Thoma Lars , Kathmann Norbert , Klawohn Julia
Published: August 2022

The error‐related negativity (ERN), a neural response to errors, has been associated with several forms of psychopathology and assumed to represent a neural risk marker for obsessive–compulsive disorder (OCD) and anxiety disorders. Yet, it is still unknown which specific symptoms or traits best explain ERN variation. This study investigated performance‐monitoring in participants (N = 100) recruited across a spectrum of obsessive–compulsive characteristics (n = 26 patients with OCD; n = 74 healthy participants including n = 24 with low, n = 24 with medium, and n = 26 with high OC‐characteristics). Several compulsivity‐ and anxiety‐associated characteristics were assessed and submitted to exploratory principal axis factor analysis. Associations of raw measures and derived factors with ERN and correct‐related negativity (CRN) were examined. Patients with OCD showed increased ERN amplitudes compared to healthy participants. The ERN was associated with a variety of traits related to anxiety and negative affect. Factor analysis results revealed a most prominent association of the ERN with a composite measure of anxiety and neuroticism, whereas the CRN was specifically associated with compulsivity. Results support differential associations for the ERN and CRN and demonstrate that a dimensional recruitment approach and use of composite measures can improve our understanding of characteristics underlying variation in neural performance monitoring.
Differential expression and functional prediction of mRNA in the ovaries of Hanper sheep of high and low fecundity
Authors: Li Yuexin , Ma Xiaofei , Gao Teng , Zheng Zhong , Liu Aiju , Tian Shujun
Published: August 2022

Hanper ewes that were either monotocous or polytocous provided ovarian follicles of diameter >3 mm in the follicular phase and, in the luteal phase, samples of corpora lutea that had developed from follicles of diameter >3 mm. Differentially expressed mRNAs (monotocous versus polytocous) were then identified, and their functions were predicted. Results showed that 1508 mRNAs were differentially expressed in the follicular phase, with 885 being in the luteal tissues. Those which were differentially expressed in the follicular phase were mainly involved in the regulation of the ferroptosis and lysosome signalling pathways, whereas, for the luteal tissue, the differentially expressed mRNAs were mainly involved in the regulation of steroid biosynthesis. Based on the results, it was inferred that these pathways could explain variations in the fecundity of sheep.
Hyperammonemia syndrome post‐lung transplantation: Case series and systematic review of literature
Authors: Buzo Bruno Fernando , Preiksaitis Jutta K. , Halloran Kieran , Nagendran Jayan , Townsend Derek R. , Zelyas Nathan , Sligl Wendy I.
Published: August 2022

Background

Hyperammonemia syndrome (HS) is a rare post‐transplant complication associated with high morbidity and mortality. Its incidence appears to be higher in lung transplant recipients and its pathophysiology is not well understood. In addition to underlying metabolic abnormalities, it is postulated that HS may be associated with Ureaplasma or Mycoplasma spp. lung infections. Management of this condition is not standardized and may include preemptive antimicrobials, renal replacement, nitrogen scavenging, and bowel decontamination therapies, as well as dietary modifications.

Methods

In this case series, we describe seven HS cases, five of whom had metabolic deficiencies ruled out. In addition, a literature review was performed by searching PubMed following PRISMA‐P guidelines. Articles containing the terms “hyperammonemia” and “lung” were reviewed from 1 January 1997 to 31 October 2021.

Results

All HS cases described in our center had positive airway samples for Mycoplasmataceae, neurologic abnormalities and high ammonia levels post‐transplant. Mortality in our group (57%) was similar to that published in previous cases. The literature review supported that HS is an early complication post‐transplant, associated with Ureaplasma spp. and Mycoplasma hominis infections and of worse prognosis in patients presenting cerebral edema and seizures.

Conclusion

This review highlights the need for rapid testing for Ureaplasma spp. and M. hominis after lung transplant, as well as the necessity for future studies to explore potential therapies that may improve outcomes in these patients.

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Keyframe Extraction for Low-Motion Video Summarization Using K-Means Clustering
Authors: Muhammad Bilyamin , Abdulazeez Ahmed Mariam , Haruna Ibrahim , Abdullahi Usman Ismail
Published: August 2022

The rate of increase in multimedia data required the need for an improved bandwidth utilization and storage capacity. However, low-motion videos come with a large number of feature-related frames due to its static background. These redundant frames result to difficulty in terms of video streaming, retrieval, and transmission. In other to improve the user experience, video summarization technologies were proposed.  These techniques were presented to select representative frames from a full-length video and remove the duplicated ones. Though, an improvement was recorded in the keyframe extraction process. However, a large number of redundant frames were observed to be extracted as keyframes. Therefore, this study presents an improved keyframe extraction scheme for low-motion video summarization. The proposed scheme utilizes a k-means clustering approach to group the feature-related frames within a given video data into number of clusters. Furthermore, a representative frame from each cluster was extracted as keyframe. The results obtained shown that  the proposed scheme outperforms the existing scheme in terms of compression ratio, precision and recall rates with a value of 26.62%, 13.78%, and 6.63% respectively
A Slotted Planar Antenna for 5G Applications
Authors: Keriee Hussam , A. Rahim Mohamad Kamal , Ayop Osman , Nayyef Nawres Abbas , Ghanim Mustafa , Alobaidi O. R. , Esmail Bashar , Hussein Yaqdhan Mahmood
Published: August 2022

This paper presents a slotted planar microstrip patch antenna for the 5th generation communication. The planar microstrip patch antenna is designed with a square patch and two longitude slots at 3.5 GHz, using FR4 substrate and feds by a coplanar waveguide structure (CPW). The proposed antenna was simulated, analysed, and optimized using computer simulation technology (CST) software. Simulation results show a good return loss of greater than10 dB and impedance bandwidth of about 650MHz, which meet the requirements of future 5G applications. In this work, the geometry of the presented antenna and its related parameters are presented and discussed
Grating Lobes Reduction in an Array Antenna Using Curved Disc Monopoles
Authors: Hachi Asmae , Hassan Lebbar , Himdi Mohamed
Published: August 2022

This paper shows the study of an array antenna with curved disc monopoles whose average spacing between elements is greater than a wavelength l0. The proposed antenna is a linear array, consisting of four equally spaced curved disc monopoles excited by a corporate feed (T-junction power divider). The single element is characterized by a directional radiation pattern in the H plane. Compared to an isotropic monopole antenna array, the proposed array reduces the grating lobes to more than -15dB. As a result, the gain will be increased. The array antenna is fabricated and measured for its impedance and radiation characteristics. The results of the simulation and measurement are in good agreement.
FDTD Analysis on WPT Efficiency Between Circuit-Shape Leaky Waveguide and 𝝀/2 Dipole Antenna for Snow Melting Application
Authors: Kanaya Yusho , Nakatsugawa Masashi , Maruyama Tamami , Omiya Manabu , Tamayama Yasuhiro
Published: August 2022

The wireless transfer characteristics between a circuit-shape leaky waveguide and a /2 dipole antenna were analyzed with scattering parameters obtained with the FDTD method. The circuit-shaped leaky waveguide was composed of two pairs of straight slotted waveguides and two semicircular waveguides. The circuit-shape leaky waveguide was designed to achieve uniform electromagnetic field distribution with a source for snow melting with microwave radiations by microwave heating. The electromagnetic field of the circuit-shape leaky waveguide was firstly simulated with the FDTD method. Although the electromagnetic distribution exhibited the point symmetry with an off-set feeding point and a slot spacing 𝝀𝒈, it was nearly uniform. The wireless transfer efficiency and the maximum transfer efficiency for four locations at 2.45 GHz revealed that the farthest location from the feeding point had the largest WPT efficiency among four locations. This ensures the circuit-shape leaky waveguide’s uniqueness. The circuit-shape leaky waveguide has favorable characteristics to provide WPT energy at any location above it.
Respiratory deficits in a female rat model of Parkinson's disease
Authors: de la Rosa Tomás , Calvo Viviam S. , Gonçalves Valeria C. , Ferreira Caroline B. , Cabral Lais M. , Souza Felipe da Costa , Scerni Débora A. , Scorza Fúlvio A. , Moreira Thiago S. , Takakura Ana C.
Published: August 2022

New Findings

What is the central question of this study?

How does the 6‐hydroxydopamine (6‐OHDA)‐induced Parkinson's disease model affect the respiratory response in female rats? What effect does ovariectomy have on that response?

What is the main finding and its importance?

The results suggest a protective effect of ovarian hormones in maintaining normal neuroanatomical integrity of the medullary respiratory nucleus in females. It was observed that ovariectomy alone reduced neurokinin‐1 density in the pre‐Bötzinger complex and Bötzinger complex, and there was an incremental effect of 6‐OHDA and ovariectomy on retrotrapezoid nucleus neurons.

Emerging evidence indicates that the course of Parkinson's disease (PD) includes autonomic and respiratory deficiencies in addition to the classical motor symptoms. The prevalence of PD is lower in women, and it has been hypothesized that neuroprotection by ovarian hormones can explain this difference. While male PD animal models present changes in the central respiratory control areas, as well as ventilatory parameters under normoxia and hypercapnia, little is known about sex differences regarding respiratory deficits in this disease background. This study aimed to explore the neuroanatomical and functional respiratory changes in intact and ovariectomized (OVX) female rats subjected to chemically induced PD via a bilateral intrastriatal injection of 6‐hydroxydopamine (6‐OHDA). The respiratory parameters were evaluated by whole‐body plethysmography, and the neuroanatomy was monitored using immunohistochemistry. It was found that dopaminergic neurons in the substantia nigra and neurokinin‐1 receptor density in the rostral ventrolateral respiratory group, Bötzinger and pre‐Bötzinger complex were reduced in the chemically induced PD animals. Additionally, reduced numbers of Phox2b neurons were only observed in the retrotrapezoid nucleus of PD‐OVX rats. Concerning respiratory parameters, in OVX rats, the resting and hypercapnia‐induced tidal volume (VT) is reduced, and ventilation () changes independently of 6‐OHDA administration. Notably, there is a reduction in the number of retrotrapezoid nucleus Phox2b neurons and hypercapnia‐induced respiratory changes in PD‐OVX animals due to a 6‐OHDA and OVX interaction. These results suggest a protective effect induced by ovarian hormones in neuroanatomical changes observed in a female experimental PD model.
Regulation of corticotropin‐releasing hormone neuronal network activity by noradrenergic stress signals
Authors: Gouws Julia M. , Sherrington Aidan , Zheng Shaojie , Kim Joon S. , Iremonger Karl J.
Published: August 2022

Noradrenaline is a neurotransmitter released in response to homeostatic challenge and activates the hypothalamic–pituitary–adrenal axis via stimulation of corticotropin‐releasing hormone (CRH) neurons. Here we investigated the mechanism through which noradrenaline regulates activity within the CRH neuronal network. Using a combination ofin vitroGCaMP6f Ca2+imaging and electrophysiology, we show that noradrenaline induces a robust increase in excitability in a proportion of CRH neurons with many neurons displaying a bursting mode of activity. Noradrenaline‐induced activation required α1‐adrenoceptors and L‐type voltage‐gated Ca2+channels, but not GABA/glutamate synaptic transmission or sodium action potentials. Exposure of mice to elevated corticosterone levels was able to suppress noradrenaline‐induced activation. These results provide further insight into the mechanisms by which noradrenaline regulates CRH neural network activity and hence stress responses.

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Key points

GCaMP6f Ca2+imaging and on‐cell patch‐clamp recordings reveal that corticotropin‐releasing hormone neurons are activated by noradrenaline with many neurons displaying a bursting mode of activity.

Noradrenaline‐induced activation requires α1‐adrenoceptors.

Noradrenaline‐induced Ca2+elevations persist after blocking GABAA, AMPA, NMDA receptors and voltage‐gated Na+channels.

Noradrenaline‐induced Ca2+elevations require L‐type voltage‐gated Ca2+channels.

Corticosterone suppresses noradrenaline‐induced excitation.
Analysis of Helical Grafts in Steady and Unsteady Flow: Development of a Novel Bypass Graft
Authors: Simpson Joseph P. , Leylek James H.
Published: August 2022

Helical secondary flow has been shown to be beneficial as it has improved bypass graft patency in revascularization through more uniform wall shear stress and improved mixing. An unfavorable by-product of generating helical flow is the proportional increase in pressure drop, which is a critical limiting factor as it constrains the amount of beneficial helicity that can be generated. A validated CFD methodology was used to simulate the development of secondary flow in multiple helical bypass grafts with Newtonian and non-Newtonian rheology. These simulations revealed that the secondary flow is fully developed by the second pitch of a helical geometry for physiologically realistic, unsteady flows, indicating the potential for maximizing secondary flows while at the same time minimizing the induced pressure drops through optimization studies. Building on this, a novel Hybrid Graft Geometry (HGG) was developed which resulted in a 390% increase in cycle-averaged helical intensity while maintaining a mere 2% increase in cycle-averaged pressure drop when compared to graft geometries in the literature. The helical effectiveness he, defined as the ratio of helical intensity to the induced pressure drop, is a newly created parameter designed to quantify the performance of the helical grafts. The cycle-averaged he clearly reveals the superior performance of the HGG, which is up to 3.6 times higher than other helical grafts tested. For the first time in the open literature, this study presents the proper basis for future optimization studies through he, which should be maximized to improve graft patency.
Calculation and measurement of center of mass: An all-in-one activity using
Tangram puzzles
Authors: Campillo-Robles Jose M. , Alonso Ibon , Gondra Ane , Gondra Nerea
Published: August 2022

[Media: see text]

We present a simple, low-cost activity for students in a university-level introductory physics course. The main objective of the activity is to calculate and experimentally measure the center of mass of a 2D Tangram figure using complementary techniques. First, the algebraic and numerical results for the center of mass of the Tangram pieces are checked analytically and using mathematical software. Students then create their own Tangram figure and calculate its center of mass using formulas from physics tables. CAD software is also used to obtain the figure's center of mass. Finally, the center of mass is measured experimentally, and a comparison with the theoretical results is made. The modularity of the activity allows instructors' flexibility to design an ad hoc activity to emphasize individual subjects according to the needs of their course.
Electrostatic shape energy differences of one-dimensional line charges
Authors: Majic Matt
Published: August 2022

We investigate the electrostatic energy of one-dimensional line charges, focusing on the energy difference between lines of different shapes. The self-energy of a strictly one-dimensional charge is infinite, but one can quantify the energy by considering geometries that approach a one-dimensional curve, for example, thin wires, thin strips, or chains of close point charges. In each model, the energy diverges logarithmically as the geometry approaches a perfect one-dimensional curve, but the energy also contains a finite term depending on the shape of the line—the “shape energy.” The difference in shape energy between a straight line and a circle is checked to be the same using a range of models. To calculate the shape energy of more complex shapes numerically, we propose a line integral where the singularity in the integrand is canceled. This integral is used to calculate the shape energy of a helix.
Apparatus and method to recover the Mueller matrix in bright-field microscopy
Authors: Obando-Vasquez Sofia , Doblas Ana , Trujillo Carlos
Published: August 2022

We present a simple experiment developed for the advanced physics instructional laboratory to calculate the Mueller matrix of a microscopic sample. The Mueller matrix is obtained from intensity-based images of the sample acquired by a polarization-sensitive microscope. The experiment requires a bright-field microscope and standard polarizing optical components such as linear polarizers and waveplates. We provide a practical procedure for implementing the apparatus, measuring the complete Mueller matrix of linear polarizers used as samples, and discuss the possibility of analyzing biological samples using our apparatus and method. Due to the simplicity of the apparatus and method, this experiment allows students to increase their knowledge about light polarization and initiate their training in optical instrumentation.
The basic concepts determining electromagnetic shielding
Authors: Vandenbosch Guy A. E.
Published: August 2022

Shielding involves much more than just putting a conductive screen in between an emitting source and a susceptible device. Starting from Maxwell's equations, the concept of electromagnetic shielding is formally explained. The physical working mechanisms behind the two basic forms of shielding, electric field and magnetic field shielding, are given, and the link between them at higher frequencies is clarified. Several aspects, like the effect of gridding or weaving a shield, the effect of the finite size of a shield, and the penetration through the metal of a shield, are discussed based on very simple canonical shielding topologies that can be solved analytically. Although the classical paradigm to explain shielding based on the notions of skin depth and eddy current is not followed, conceptual links with this classical paradigm are explained.
Comment on “A study of the longitudinal laser modes of a semiconductor laser using optical coherence tomography” [Am. J. Phys. 75, 569–571 (2006)]
Authors: Aljalal Abdulaziz M.
Published: August 2022

Although the longitudinal mode spacing and longitudinal mode widths of a typical laser diode can, in principle, be determined from an optical coherence tomography signal, the values presented by Poddar et al. [Am. J. Phys. 75, 569–571 (2006)] do not agree with the Fourier transform theory. Also, the mode spacing is inconsistent with the peak separation in the interference signal. Moreover, the laser cavity mirror reflectivity calculated from the laser spectrum is incorrect because it ignores the gain and the loss within the laser cavity. This Comment aims to help readers who may struggle to understand that paper or to reproduce its results.
Antibiotic Changes Host Susceptibility to Eimeria falciformis Infection Associated with Alteration of Gut Microbiota
Authors: Gong Yujiao , Liu Xianyong , Zhang Sixin , Tang Xinming , Zou Jun , Suo Xun
Published: August 2022

Eimeria falciformis
is a murine-infecting coccidium that mainly infects the cecum and colon where it coexists with a large number of endogenous bacteria. Here, we found that mice treated with a broad-spectrum antibiotic cocktail including ampicillin, neomycin, metronidazole, and vancomycin had less oocyst production and milder pathological consequences after
E. falciformis
infection than mice without antibiotics, regardless of the inoculation doses. Furthermore, we showed that antibiotic treatment reduced parasitic invasion and prolonged asexual stage during
E. falciformis
infection, which may result in alleviating the infection.
Elucidation of Key Interactions between VirF and the
virB
Promoter in Shigella flexneri Using E. coli MarA- and GadX-Based Homology Models and
In Vitro
Analysis of the DNA-Binding Domains of VirF and MarA
Authors: Ragazzone Nicholas J. , Dow Garrett T. , Garcia George A.
Published: August 2022

Globally, infection with
Shigella flexneri
is a leading cause of bacterial dysentery, particularly affecting children under the age of 5 years. The virulence of this pathogen makes it highly infectious, allowing it to spread easily within areas lacking proper sanitation or access to clean drinking water.
Reverse innovation in western healthcare: a randomised crossover trial comparing the ReMotion prosthetic knee with the current standard of care
Authors: van Oorschot Wieneke , Keijsers Noël L W , van Ee René F , van Houdenhoven Mark
Published: August 2022

Introduction

Healthcare expenses are reaching unaffordable levels worldwide and reverse innovation could play a role in decreasing these expenses and improving healthcare accessibility. The ReMotion Knee, a prosthetic knee primarily developed for low-income countries, could serve as a reverse innovation for people with a lower limb amputation. This study aimed to evaluate the ReMotion Knee as a potential reverse innovation in high-income countries, specifically in terms of functional mobility.

Methods

Nine participants with a transfemoral amputation or knee exarticulation were included in this randomised crossover trial. The ReMotion Knee was compared with the participants’ current prosthetic knee in terms of functional mobility and subjective experiences. The primary outcome in this study was the L test for functional mobility. Secondary outcomes were additional clinical performance tests and subjective experiences (balance confidence, walking comfort, test performance and fatigue).

Results

Participants scored significantly better using their current prosthetic knee than using the ReMotion Knee on primary outcome, the L test (p<0.01, median difference 7.5 s, IQR 6.1–10.6) and all secondary outcomes except experienced test performance and fatigue. All participants were able to safely perform all clinical tests with the ReMotion Knee, even after a short familiarisation period.

Conclusions

The ReMotion Knee has the potential to become a reverse innovation after modifications improving velocity, walking comfort and weight limit. Collaboration between high-income and low-income countries can facilitate further development of the ReMotion Knee and could result in alternative products and treatments that could reduce healthcare costs while still providing a good quality of care.

Trial registration number

NCT04700085.
Development and validation of automated computer-aided risk scores to predict in-hospital mortality for emergency medical admissions with COVID-19: a retrospective cohort development and validation study
Authors: Faisal Muhammad , Mohammed Mohammed , Richardson Donald , Fiori Massimo , Beatson Kevin
Published: August 2022

Objectives

There are no established mortality risk equations specifically for unplanned emergency medical admissions which include patients with SARS-19 (COVID-19). We aim to develop and validate a computer-aided risk score (CARMc19) for predicting mortality risk by combining COVID-19 status, the first electronically recorded blood test results and the National Early Warning Score (NEWS2).

Design

Logistic regression model development and validation study.

Setting

Two acute hospitals (York Hospital—model development data; Scarborough Hospital—external validation data).

Participants

Adult (aged ≥16 years) medical admissions discharged over a 24-month period with electronic NEWS and blood test results recorded on admission. We used logistic regression modelling to predict the risk of in-hospital mortality using two models: (1) CARMc19_N: age+sex+NEWS2 including subcomponents+COVID19; (2) CARMc19_NB: CARMc19_N in conjunction with seven blood test results and acute kidney injury score. Model performance was evaluated according to discrimination (c-statistic), calibration (graphically) and clinical usefulness at NEWS2 thresholds of 4+, 5+, 6+.

Results

The risk of in-hospital mortality following emergency medical admission was similar in development and validation datasets (8.4% vs 8.2%). The c-statistics for predicting mortality for CARMc19_NB is better than CARMc19_N in the validation dataset (CARMc19_NB=0.88 (95% CI 0.86 to 0.90) vs CARMc19_N=0.86 (95% CI 0.83 to 0.88)). Both models had good calibration (CARMc19_NB=1.01 (95% CI 0.88 to 1.14) and CARMc19_N:0.95 (95% CI 0.83 to 1.06)). At all NEWS2 thresholds (4+, 5+, 6+) model, CARMc19_NB had better sensitivity and similar specificity.

Conclusions

We have developed a validated CARMc19 scores with good performance characteristics for predicting the risk of in-hospital mortality. Since the CARMc19 scores place no additional data collection burden on clinicians, it may now be carefully introduced and evaluated in hospitals with sufficient informatics infrastructure.