bluuebunny/crossref_metadata_2025 huggingface dataset:
Surveillance testing for SARS-COV-2 infection in an asymptomatic athlete population: a prospective cohort study with 123 362 tests and 23 463 paired RT-PCR/antigen samples
Authors: Harmon Kimberly , de St Maurice Anabelle M , Brady Adam C , Swaminathan Sankar , Aukerman Doug F , Rueda Miguel A , Terrell Kim , Cohen Randall P , Gamradt Seth C , Henry Sunday D , Huston Lindsay M , McAllister David R , McCarty Kenneth M , Pass Anthony N , Paul Stephen R , Petron David J , Kliethermes Stephanie A
Published: June 2021

Objective

To assess the diagnostic accuracy of antigen compared with reverse transcriptase (RT)-PCR testing in an asymptomatic athlete screening programme and to monitor infection in college athletes.

Methods

Quidel Sofia-2 SARS-CoV-2 Antigen Tests were performed daily before sports participation for football, basketball, wrestling and water polo from 29 September 2020 to 28 February 2021. Paired RT-PCR and antigen tests were performed at least once a week. Positive antigen tests were confirmed with RT-PCR.

Results

81 175 antigen and 42 187 RT-PCR tests were performed, including 23 462 weekly paired antigen/RT-PCR screening tests in 1931 athletes. One hundred and seventy-two athletes had a positive screening RT-PCR (0.4%), of which 83 (48%) occurred on paired testing days. The sensitivity of antigen tests varied with the frequency of RT-PCR testing and prevalence of COVID-19. The sensitivity of antigen testing was 35.7% (95% CI: 17% to 60%) and specificity 99.8% (95% CI: 99.7% to 99.9%) with once-a-week RT-PCR testing after adjusting for school prevalence. Daily antigen testing was similar to RT-PCR testing two to three times a week in identifying infection. Antigen testing identified infection before the next scheduled PCR on 89 occasions and resulted in 234 days where potentially infectious athletes were isolated before they would have been isolated with RT-PCR testing alone. Two athletic-related outbreaks occurred; 86% of total infections were community acquired.

Conclusion

Antigen testing has high specificity with a short turnaround time but is not as sensitive as RT-PCR. Daily antigen testing or RT-PCR testing two to three times a week is similar. There are benefits and drawbacks to each testing approach.
Experiences of fathers of children with a life-limiting condition: a systematic review and qualitative synthesis
Authors: Fisher Victoria , Fraser Lorna , Taylor Johanna
Published: June 2021

Background

Children with a life-limiting condition often require extensive and complex care, much of which is provided by their parents at home. There is a growing body of research that aims to understand the experiences of these parents, but the majority of this research is from mothers’ perspectives, meaning that fathers’ experiences are not well understood.

Objectives

To identify and synthesise findings from existing qualitative studies that have explored the experiences of fathers of children with a life-limiting condition.

Methods

A systematic review of qualitative research was conducted using thematic synthesis. Searches were conducted in MEDLINE, CINAHL, EMBASE, PsycINFO and Social Science Citation Index.

Results

Findings from 30 studies were included, representing the experiences of 576 fathers of children with a range of diagnoses including cancer, cystic fibrosis, genetic and neurological conditions. Themes detailed fathers’ experiences of uncertainty and shock around the time of their child’s diagnosis, their accounts of a ‘new normal’, difficulties in discussing their emotions, forming relationships with and seeking support from professionals and working fathers’ role conflicts. They discussed the life-changing nature of their child’s diagnosis, an event that affected all aspects of their lives from everyday activities, to their relationships, spirituality, values and ambitions.

Conclusions

Fathers experience many difficulties in response to their child’s diagnosis and ongoing treatment. Findings highlight the need for healthcare professionals to recognise individual family dynamics and the evolving role of the father. Fathers’ responses are not widely understood, and research that directly addresses their own well-being is warranted.
Sexually transmitted infection laboratory testing and education trends in US outpatient physician offices, 2009–2016
Authors: Zeidan Amina R , Strey Kelsey , Vargas Michelle N , Reveles Kelly R
Published: June 2021

Objective

To describe national rates of sexually transmitted infection (STI) testing and education overall and among patient subgroups in US outpatient physician offices from 2009 to 2016.

Design

This was a cross-sectional study of the Centers for Disease Control and Prevention’s National Ambulatory Medical Care Survey from 2009 to 2016. Data weights were applied to extrapolate to national estimates.

Setting

Data were collected from a systematic random sample of outpatient physician office visits throughout USA. Physician office types include free standing clinics, private or group setting practices, centres offering community and mental health services, family planning clinics and health maintenance organisations/other prepaid clinics.

Participants

All sampled patient visits were eligible for inclusion and were assessed for the provision of STI prevention education and STI testing for chlamydia, gonorrhoea, hepatitis, human papillomavirus (HPV) and HIV.

Results

Of 7.6 billion total visits, 123 million included an STI test. Hepatitis was the most commonly tested STI (9.12 per 1000), followed by chlamydia (6.67 per 1000), gonorrhoea (6.00 per 1000), HIV (5.40 per 1000) and HPV (5.03 per 1000). Testing rates for the three STIs measured for the entire 8-year period increased over time and peaked in 2015 compared with 2009: chlamydia (R2=0.36), HPV (R2=0.28) and HIV (R2=0.51). Testing was highest among women (21.93 per 1000), 15–24-year olds (46.04 per 1000), non-Hispanic blacks (37.33 per 1000) and those seen by obstetrics/gynaecology specialists (103.75 per 1000). STI prevention education was provided to 4.89 per 1000 patients and remained relatively unchanged from 2013 to 2016.

Conclusion

STI testing in outpatient physician offices increased over the study period but varied by patient characteristics and site of care. Few patients received STI prevention education, highlighting a potential gap in resource utilisation in these settings.
Mastering stakeholders’ engagement to reach national scale, sustainability and wide adoption of digital health initiatives: lessons learnt from Burkina Faso
Authors: Lampariello Riccardo , Ancellin-Panzani Sonia
Published: June 2021

Although low-income countries have recently seen an exponential flourishing of digital health initiatives, the landscape is characterised by a myriad of small pilots that rarely reach scaling, sustainability and wide adoption. The case of Burkina Faso represents an exception where a digital health initiative initially conceived to improve the diagnosis of sick children under 5 has supported millions of consultations. Technical aspects such as interoperability, standardisation, and adaptation to the existing infrastructure were considered as they are prerequisites for scaling; so was the demonstration of the health impact and affordability of the initiative. Beyond those factors which are largely documented in the literature, the experience in Burkina Faso showed that the positive outcome was also determined by the support of numerous stakeholders. A vast network of stakeholders from the Ministry of Health to child caregivers is involved and each of them could have either blocked or promoted the digital health initiative. Thanks to an extensive, time-consuming and tailored stakeholder strategy, it was possible to avoid potential blockages from multiple actors and gain their engagement.
STING activation normalizes the intraperitoneal vascular-immune microenvironment and suppresses peritoneal carcinomatosis of colon cancer
Authors: Lee Seung Joon , Yang Hannah , Kim Woo Ram , Lee Yu Seong , Lee Won Suk , Kong So Jung , Lee Hye Jin , Kim Jeong Hun , Cheon Jaekyung , Kang Beodeul , Chon Hong Jae , Kim Chan
Published: June 2021

Background

Peritoneal carcinomatosis is a fatal clinical presentation of colon cancer, characterized by unresponsiveness to conventional anticancer therapies, including immune checkpoint inhibitors. Here, we elucidated the immune-evasion mechanisms during the peritoneal carcinomatosis of colon cancer and developed a novel immunotherapy by activating the stimulator of interferon genes (STING) pathway.

Methods

We generated a syngeneic peritoneal carcinomatosis model of colon cancer. Mice were intraperitoneally treated with either STING agonist (MIW815, also known as ADU-S100) or PD-1 blockade or both. The tumor microenvironment was comprehensively analyzed using multiplexed immunofluorescence imaging, flow cytometry, and NanoString immune profiling.

Results

Intraperitoneal colon cancer cells induce a massive influx of immunosuppressive M2-like macrophages, upregulate immune checkpoints, and impair effector T cell functions during peritoneal dissemination; these collectively create a highly angiogenic and immunosuppressive milieu that is resistant to anti-PD-1 monotherapy. Intraperitoneal administration of a STING agonist suppressed aberrant angiogenesis, increased pericyte coverage, and normalized tumor vessels, thereby facilitating the infiltration of activated CD8+ T cells into peritoneal tumor nodules. Moreover, STING activation reprogramed tumor-associated macrophages toward the M1 phenotype. STING activation converted immunologically cold peritoneal tumors into T-cell-inflamed tumors in a type-I interferon-dependent manner. Lastly, the STING agonist synergistically cooperated with PD-1 and/or COX2 blockade to further suppress the peritoneal dissemination of colon cancer, resulting in complete eradication of tumor and ascites, and inducing durable antitumor immunity.

Conclusions

STING activation can normalize the peritoneal vascular and immune microenvironment, providing a rationale for a novel combination therapeutic strategy for peritoneal carcinomatosis in colon cancer.
Biallelic truncating variants in ATP9A cause a novel neurodevelopmental disorder involving postnatal microcephaly and failure to thrive
Authors: Vogt Guido , Verheyen Sarah , Schwartzmann Sarina , Ehmke Nadja , Potratz Cornelia , Schwerin-Nagel Anette , Plecko Barbara , Holtgrewe Manuel , Seelow Dominik , Blatterer Jasmin , Speicher Michael R , Kornak Uwe , Horn Denise , Mundlos Stefan , Fischer-Zirnsak Björn , Boschann Felix
Published: June 2021

Background

Genes implicated in the Golgi and endosomal trafficking machinery are crucial for brain development, and mutations in them are particularly associated with postnatal microcephaly (POM).

Methods

Exome sequencing was performed in three affected individuals from two unrelated consanguineous families presenting with delayed neurodevelopment, intellectual disability of variable degree, POM and failure to thrive. Patient-derived fibroblasts were tested for functional effects of the variants.

Results

We detected homozygous truncating variants in ATP9A. While the variant in family A is predicted to result in an early premature termination codon, the variant in family B affects a canonical splice site. Both variants lead to a substantial reduction of ATP9A mRNA expression. It has been shown previously that ATP9A localises to early and recycling endosomes, whereas its depletion leads to altered gene expression of components from this compartment. Consistent with previous findings, we also observed overexpression of ARPC3 and SNX3, genes strongly interacting with ATP9A.

Conclusion

In aggregate, our findings show that pathogenic variants in ATP9A cause a novel autosomal recessive neurodevelopmental disorder with POM. While the physiological function of endogenous ATP9A is still largely elusive, our results underline a crucial role of this gene in endosomal transport in brain tissue.
Mortality in hypotensive trauma patients requiring laparotomy is related to degree of hypotension and provides evidence for focused interventions
Authors: Davis James W , Dirks Rachel C , Jeffcoach David R , Kaups Krista L , Sue Lawrence P , Lilienstein Jordan T , Wolfe Mary M , Kwok Amy M
Published: June 2021

Background

Mortality in hypotensive patients requiring laparotomy is reported to be 46% and essentially unchanged in 20 years. Resuscitative endovascular balloon occlusion of the aorta (REBOA) has been incorporated into resuscitation protocols in an attempt to decrease mortality, but REBOA can have significant complications and its use in this patient group has not been validated. This study sought to determine the mortality rate for hypotensive patients requiring laparotomy and to evaluate the mortality risk related to the degree of hypotension. Additionally, this study sought to determine if there was a presenting systolic blood pressure (SBP) that was associated with a sharp increase in mortality to target the appropriate patient group most likely to benefit from focused interventions such as REBOA.

Methods

The trauma registry at a level I trauma center was reviewed for patients undergoing emergent laparotomy from January 2007 to June 2020. Data included demographics, mechanism of injury, physiological data, Injury Severity Score, blood products transfused, and outcomes. Group comparisons were based on initial SBP (0 to 50 mm Hg, 60 to 69 mm Hg, 70 to 79 mm Hg, 80 to 89 mm Hg, and ≥90 mm Hg).

Results

During the study period, 52 016 trauma patients were treated and 1174 required laparotomy within 90 min of arrival; 424 had an initial SBP of <90 mm Hg. The overall mortality rate was 18%, but mortality increased as SBP decreased (≥90=9%, 80 to 89=20%, 70 to 79=21%, 60 to 69=48%, 0 to 59=66%). Mortality increased sharply with SBP of <70 mm Hg.

Discussion

Mortality rate increases with worsening hypotension and increases sharply with an SBP of <70 mm Hg. Further study on focused interventions such as REBOA should target this patient group.

Level of evidence

Therapeutic/care management, level III.
On the ocean beach—why elliptic pebbles do not become spherical
Authors: Winzer Klaus , Hegerfeldt Gerhard C.
Published: June 2021

Among pebbles strewn across a sandy ocean beach, one can find relatively many with a nearly perfect elliptical (ellipsoidal) shape, and one wonders how this shape was attained and whether, during abrasion, the pebbles would remain elliptical or eventually become spherical. Mainly the latter question was addressed in a previous publication which identified frictional sliding and rotation of an elliptic pebble as main abrasion processes in the surf waves. In particular, it was predicted that the ellipticity $$\varepsilon = \left\{ {1 - b^{2} /a^{2} } \right\}^{1/2}$$

ε
=

1
-

b
2

/

a
2

1
/
2

(a > b, principal ellipse axes) converges to a common equilibrium value for elliptic-like pebbles. Unfortunately, the derivation was based on an invalid force expression and a dimensionally unsuitable curvature. In this paper, not only force and curvature but also the contact duration with the sand surface during rotations is taken into account by fairly simple physical arguments, and it is shown that elliptic pebbles neither approach the same ellipticity and nor become more spherical nor more disk-like but rather that the ellipticity $$\varepsilon$$
ε
increases.
Comparison of Buffer Layer Grading Approaches in InGaAs/GaAs (001)
Authors: Raphael Johanna , Kujofsa Tedi , Ayers J. E.
Published: June 2021

Metamorphic semiconductor devices often utilize compositionally-graded buffer layers for the accommodation of the lattice mismatch with controlled threading dislocation density and residual strain. Linear or step-graded buffers have been used extensively in these applications, but there are indications that sublinear, superlinear, S-graded, or overshoot graded structures could offer advantages in the control of defect densities. In this work we compare linear, step-graded, and nonlinear grading approaches in terms of the resulting strain and dislocations density profiles using a state-of-the-art model for strain relaxation and dislocation dynamics. We find that sublinear grading results in lower surface dislocation densities than either linear or superlinear grading approaches.
A Novel Addressing Circuit for SWS-FET Based Multivalued Dynamic Random-Access Memory Array
Authors: Gudlavalleti R. H. , Saman B. , Mays R. , Salama H. , Heller Evan , Chandy J. , Jain F.
Published: June 2021

Multivalued memory increases the bits-per-cell storage capacity over conventional one transistor (1T) MOS based dynamic random-access memory (DRAM) by storing more than two data signal levels in each unit memory cell. A spatial wavefunction switched (SWS) field effect transistor (FET) has two vertically stacked quantum-well/quantum-dot channels between the source and drain regions. The charge location in upper or lower quantum channel region is based on the input gate voltage. A multivalued DRAM that can store more than two bits-per-cell was implemented by using one SWS-FET (1T) device and two capacitors (2C) connected to each source regions of the SWS-FET device. This paper proposes the architecture and design of peripheral circuitry that includes row/column address decoding and sensing circuit for a multivalued DRAM crossbar arrays. The SWS-FET device was modeled using analog behavioral modeling (ABM) with two transistors using conventional BSIM 3V3 device parameters in 90 nm technology. The Cadence circuit schematic simulations are presented. A compact multivalued DRAM architecture presents a new paradigm in terms of application in Neural systems that demand storage of multiple valued levels.
Systems for Implementing Data Communication with Security Tokens
Authors: Chang Milton , Das Santanu , Montrone Dale , Chakraborty Tapan
Published: June 2021

This paper proposes a novel scheme for inter-connecting IOT devices with servers. To overcome the drawbacks and other shortcomings of existing IoT network schemes, a new approach to IoT device certification and inter-connecting IoT devices to other network devices (e.g., aggregators and servers) is described. The proposed approach ensures that the overall IoT network is “hardened” against attack and meets the stringent requirements of mission critical applications.
QDC-FET and QD-SWS Physics-Based Equivalent Circuit for ABM Simulations
Authors: Mays R. , Gudlavalleti R. H. , Khan B. , Saman B. , Chandy J. , Heller Evan , Jain F.
Published: June 2021

This paper investigates physics based equivalent circuits for spatial wavefunctions switched (SWS) field-effect transistors (FETs). This will lead to improved analog behavioral models (ABMs) for 2-bit/4-state logic gates, SRAMs, and registers. Model parameters related to 65 nm technology were used to simulate ID-VD characteristics, transconductance gm and channel conductance gD using Cadence. SWSFET physics based analytical equations were used to simulate using MATLAB SIMULINK and compare with Cadence simulations. Equivalent circuit utilizes different values of equivalent oxide thickness for the lower W2 and upper W1 quantum well channels. The methodology is similarly applicable to two-channel quantum dot FET. The methodology can be further extended to model and simulate multiple channel SWS-FET devices.
Effects of Berberine on Diabetes and Cognitive Impairment in an Animal Model: The Mechanisms of Action
Authors: Zhang Jing-Hua , Zhang Jin-Feng , Song Jun , Bai Yu , Deng Lan , Feng Chun-Peng , Xu Xin-Yao , Guo Hong-Xia , Wang Yi , Gao Xin , Gu Yan , Jin Chuan , Zheng Jun-Fu , Zhen Zhong , Su Hao
Published: June 2021

Diabetes is a group of metabolic disorders with an increased risk of developing cognitive impairment and dementia. The hippocampus in the forebrain contains an abundance of insulin receptors related to cognitive function and plays an important role in the pathophysiology of neurodegenerative disorders. Berberine from traditional Chinese medicine has been used to treat diabetes and diabetic cognitive impairment, although its related mechanisms are largely unknown. In this study, a STZ diabetes rat model feeding with a high-fat diet was used to test the effects of berberine compared with metformin. Oral glucose tolerance and hyperinsulinemic-euglycemic clamp were used for glucose metabolism and insulin resistance. The Morris water maze was used to observe the compound effects on cognitive impairment. Serum and hippocampal [Formula: see text]-amyloid peptide (A[Formula: see text], Tau and phosphorylated Tau protein deposition in the hippocampi were measured. The TUNEL assay was used to detect the neuronal apoptosis, supported by histomorphological changes and transmissional electron microscopy (TEM) image. Our data showed that the diabetic rats had a significantly cognitive impairment. In addition to improving glucose metabolism and reducing insulin resistance, berberine significantly improved the cognitive function in the rat. Berberine also effectively decreased the expression of hippocampal tau protein, phosphorylated Tau, and increased insulin receptor antibodies. Moreover, berberine downregulated the abnormal phosphorylation of A[Formula: see text] and Tau protein and improved hippocampal insulin signaling. The TUNEL assay confirmed that berberine reduced hippocampal neuronal apoptosis supported by TEM. Thus, berberine significantly improved the cognitive function in diabetic rats by changing the peripheral and central insulin resistance. The reduction of neuronal injury, A[Formula: see text] deposition, abnormal phosphorylation of Tau protein, and neuronal apoptosis in the hippocampus were observed as the related mechanisms of action.
Investigation of the impact of mole-fraction on the digital benchmarking parameters as well as sensitivity in GaXIn1−XAs/GaYIn1−YSb vertical heterojunctionless tunneling field effect transistor
Authors: Rajabi Behzad , Vadizadeh Mahdi
Published: June 2021

Ga[Formula: see text]In[Formula: see text]As/Ga[Formula: see text]In[Formula: see text]Sb vertical heterojunctionless tunneling field effect transistor (VHJL-TFET) has been suggested to optimize the digital benchmarking parameters. In the proposed VHJL-TFET with type II heterostructure (i.e., [Formula: see text] and [Formula: see text]), slight changes in gate voltage cause switching from OFF-state to ON-state. As a result, the electrical properties of Ga[Formula: see text]In[Formula: see text]As/Ga[Formula: see text]In[Formula: see text]Sb VHJL-TFET are excellent in the sub-threshold region. The heterostructure with III–V semiconductors in the source-channel region increases the ON-state current ([Formula: see text]) of the VHJL-TFET. Comparing the results of Ga[Formula: see text]In[Formula: see text]As/Ga[Formula: see text]In[Formula: see text]Sb VHJL-TFET with the simulated devices with type I heterostructure (i.e., [Formula: see text] and [Formula: see text]) and type III heterostructure (i.e., [Formula: see text] and [Formula: see text]) shows the improvement by 26% and 15% in the average subthreshold slope (SS). Sensitivity analysis for VHJL-TFET with the type II heterostructure shows that the sensitivity of OFF-state current ([Formula: see text] to the body thickness ([Formula: see text] and doping concentration ([Formula: see text] is more than the sensitivity of the other main electrical parameters. The Ga[Formula: see text]In[Formula: see text]As/Ga[Formula: see text]In[Formula: see text]Sb VHJL-TFET with a channel length of 20 nm, [Formula: see text] nm, and [Formula: see text] cm[Formula: see text] showed the [Formula: see text] mV/dec, [Formula: see text]/[Formula: see text], and [Formula: see text] mA/um. As a result, Ga[Formula: see text]In[Formula: see text]As/Ga[Formula: see text]In[Formula: see text]Sb VHJL-TFET can be a reasonable choice for digital applications.
Codimension-3 Bifurcation in the p53 Regulatory Network Model
Authors: Jiang Cuicui , Zhang Yongxin , Wang Wendi
Published: June 2021

In this paper, a p53-Mdm2 mathematical model is analyzed to understand the biological implications of feedback loops in a p53 system. Results show that the model can undergo four types of codimension-3 Bogdanov–Takens bifurcations, including cusp, saddle, focus and elliptic. Specifically, we find new phenomena including the coexistence of four positive equilibria, two limit cycles, the coexistence of three stable states (two stable equilibria and one stable limit cycle, or three stable equilibria), a heteroclinic loop enclosing a smaller stable limit cycle and a larger stable limit cycle. These findings extend the understanding of the complex dynamics of the p53 system, and can provide some potential biological applications.
Exact Universal Excitation Waveform for Optimal Enhancement of Directed Ratchet Transport
Authors: Chacón Ricardo , Martínez Pedro J.
Published: June 2021

We show the existence and properties of an exact universal excitation waveform for optimal enhancement of directed ratchet transport (in the sense of the average velocity) by providing three alternative derivations. Specifically, it is deduced from the criticality scenario giving rise to ratchet universality as well as from an approach based on Fokker–Planck’s equation. Numerical experiments confirmed the existence of such exact universal excitation waveform in the context of a driven overdamped Brownian particle subjected to a periodic potential. While the universality scenario holds regardless of the waveform of the periodic vibratory excitations involved, it is shown that the enhancement of directed ratchet transport is optimal when the impulse transmitted by those excitations (time integral over a half-period) is maximum.
An abstract inf-sup problem inspired by limit analysis in perfect plasticity and related applications
Authors: Sysala Stanislav , Haslinger Jaroslav , Reddy B. Daya , Repin Sergey
Published: June 2021

This paper is concerned with an abstract inf-sup problem generated by a bilinear Lagrangian and convex constraints. We study the conditions that guarantee no gap between the inf-sup and related sup-inf problems. The key assumption introduced in the paper generalizes the well-known Babuška–Brezzi condition. It is based on an inf-sup condition defined for convex cones in function spaces. We also apply a regularization method convenient for solving the inf-sup problem and derive a computable majorant of the critical (inf-sup) value, which can be used in a posteriori error analysis of numerical results. Results obtained for the abstract problem are applied to continuum mechanics. In particular, examples of limit load problems and similar ones arising in classical plasticity, gradient plasticity and delamination are introduced.
The Influence of Sentiment Orientation in Open Innovation Communities: Empirical Evidence from a Business Analytics Community
Authors: Daradkeh Mohammad
Published: June 2021

This study aims to investigate the influence of presentation and sentiment orientation of user-generated ideas and reviews on idea adoption in open innovation communities (OICs). Drawing on the social influence theory, this study develops a research model that divides idea components into informational and normative determinants. The sentiment orientation of the idea title, description, and associated reviews is determined using a lexicon-based sentiment analysis approach. The research model is empirically tested using logistic regression analysis based on a dataset from the Microsoft community for business analytics products. The results reveal that the sentiment orientation of idea title has a negative influence on idea adoption, whilst the sentiment orientation of description has no influence on idea adoption. The sentiment orientation of the associated reviews has a positive influence on idea adoption, and this influence is moderated by the number of reviews. In addition, both idea title length and description length have a positive influence on idea adoption. These results offer several theoretical and practical implications and should therefore contribute to a better understanding of how user-generated ideas can be leveraged to drive innovation development and sustainability in OICs.
A note on Reissner–Nordström black holes in the inverse electrodynamics model
Authors: Mazharimousavi S. Habib
Published: June 2021

Recently, the inverse electrodynamics model (IEM) was introduced and applied to find Reissner–Nordström black holes in the context of the general relativity coupled minimally with the nonlinear electrodynamics. The solution consists of both electric and magnetic fields as of the dyonic solutions. Here, in this note, we show that the IEM model belongs to a more general class of the nonlinear electrodynamics with [Formula: see text]. Here, [Formula: see text] is the energy momentum tensor of the nonlinear electrodynamic Lagrangian. Naturally, such a dyonic RN black hole solution is the solution for this general class.
On triangulable tensor products of B-pairs and trianguline representations
Authors: Berger Laurent , Di Matteo Giovanni
Published: June 2021

We show that if [Formula: see text] and [Formula: see text] are two [Formula: see text]-adic representations of [Formula: see text] whose tensor product is trianguline, then [Formula: see text] and [Formula: see text] are both potentially trianguline.
Influence of CuO addition on dielectric and piezoelectric properties of (Bi0.5Na0.5)TiO3–BaTiO3lead-free piezoceramics
Authors: Difeo M. , Ramajo L. , Castro M.
Published: June 2021

Doping effects of CuO on the sintering behavior and electrical properties of 0.94([Formula: see text][Formula: see text]TiO3–0.06([Formula: see text]–[Formula: see text]CuO (BNT–BT6–[Formula: see text]Cu) lead-free piezoceramic obtained by the conventional solid-state reaction method were investigated. Regarding the undoped system, it is already known that it presents the best densification values when it is sintered at 1150[Formula: see text]C, however, the doped system was sintered at 1150[Formula: see text]C, 1100[Formula: see text]C, 1050[Formula: see text]C, 1025[Formula: see text]C, and 975[Formula: see text]C to determine the effect of Cu on the densification process. Therefore, it was obtained that the CuO-doped samples sintered at 1050[Formula: see text]C presented the highest density values and therefore were the ones chosen to perform the characterization tests together with the undoped system. The samples were characterized using X-ray diffraction (XRD), Raman microspectroscopy, and scanning electron microscopy (SEM) analysis, whereas the ferroelectric and dielectric properties were evaluated by means of ferroelectric hysteresis loops and impedance spectroscopy studies. As a result, the addition of CuO allowed an improvement in sinterability and densification, with the subsequent grain growth, and the improvement of the piezoelectric coefficient ([Formula: see text].
China’s Engagements in Africa: Is China a “Partner” or a “Predator”?
Authors: Armel Kaze
Published: June 2021

From modest beginnings in 1960, China has expanded its foreign assistance and investments in Africa and has recently become a highly visible actor in Africa’s lending landscape. With China’s financial support, African countries are transitioning from “poor countries” to “developing countries”, and China’s investments in Africa have made the continent more attractive to other external investors. However, China’s engagements in Africa are labeled in extreme connotations as either being the best economic “Partner” that Africa has had since the post-colonial era or just the latest “Predator” coming to pillage Africa’s remaining natural resources. Why such connotations? Why do media around the world, especially Western media, criticize China’s engagements in Africa? Is it because China has threatened Western countries’ interests in Africa or is it about the overhyped debate about African countries’ high “external debt” problem? Using mixed qualitative and quantitative methods, this paper examines those critics who argue that recognizing China’s engagements in Africa is the first step toward understanding China’s “peaceful rise” and hopefully stymie further false accusations.
Robust Image Representation via Low Rank Locality Preserving Projection
Authors: Yin Shuai , Sun Yanfeng , Gao Junbin , Hu Yongli , Wang Boyue , Yin Baocai
Published: June 2021

Locality preserving projection (LPP) is a dimensionality reduction algorithm preserving the neighhorhood graph structure of data. However, the conventional LPP is sensitive to outliers existing in data. This article proposes a novel low-rank LPP model called LR-LPP. In this new model, original data are decomposed into the clean intrinsic component and noise component. Then the projective matrix is learned based on the clean intrinsic component which is encoded in low-rank features. The noise component is constrained by theℓ1-norm which is more robust to outliers. Finally, LR-LPP model is extended to LR-FLPP in which low-dimensional feature is measured by F-norm. LR-FLPP will reduce aggregated error and weaken the effect of outliers, which will make the proposed LR-FLPP even more robust for outliers. The experimental results on public image databases demonstrate the effectiveness of the proposed LR-LPP and LR-FLPP.
Dissipation of Light Energy Absorbed in Excess: The Molecular Mechanisms
Authors: Bassi Roberto , Dall'Osto Luca
Published: June 2021

Light is essential for photosynthesis. Nevertheless, its intensity widely changes depending on time of day, weather, season, and localization of individual leaves within canopies. This variability means that light collected by the light-harvesting system is often in excess with respect to photon fluence or spectral quality in the context of the capacity of photosynthetic metabolism to use ATP and reductants produced from the light reactions. Absorption of excess light can lead to increased production of excited, highly reactive intermediates, which expose photosynthetic organisms to serious risks of oxidative damage. Prevention and management of such stress are performed by photoprotective mechanisms, which operate by cutting down light absorption, limiting the generation of redox-active molecules, or scavenging reactive oxygen species that are released despite the operation of preventive mechanisms. Here, we describe the major physiological and molecular mechanisms of photoprotection involved in the harmless removal of the excess light energy absorbed by green algae and land plants. In vivo analyses of mutants targeting photosynthetic components and the enhanced resolution of spectroscopic techniques have highlighted specific mechanisms protecting the photosynthetic apparatus from overexcitation. Recent findings unveil a network of multiple interacting elements, the reaction times of which vary from a millisecond to weeks, that continuously maintain photosynthetic organisms within the narrow safety range between efficient light harvesting and photoprotection.
The Cold Region Critical Zone in Transition: Responses to Climate Warming and Land Use Change
Authors: Pi Kunfu , Bieroza Magdalena , Brouchkov Anatoli , Chen Weitao , Dufour Louis J.P. , Gongalsky Konstantin B. , Herrmann Anke M. , Krab Eveline J. , Landesman Catherine , Laverman Anniet M. , Mazei Natalia , Mazei Yuri , Öquist Mats G. , Peichl Matthias , Pozdniakov Sergey , Rezanezhad Fereidoun , Roose-Amsaleg Céline , Shatilovich Anastasia , Shi Andong , Smeaton Christina M. , Tong Lei , Tsyganov Andrey N. , Van Cappellen Philippe
Published: June 2021

Global climate warming disproportionately affects high-latitude and mountainous terrestrial ecosystems. Warming is accompanied by permafrost thaw, shorter winters, earlier snowmelt, more intense soil freeze-thaw cycles, drier summers, and longer fire seasons. These environmental changes in turn impact surface water and groundwater flow regimes, water quality, greenhouse gas emissions, soil stability, vegetation cover, and soil (micro)biological communities. Warming also facilitates agricultural expansion, urban growth, and natural resource development, adding growing anthropogenic pressures to cold regions’ landscapes, soil health, and biodiversity. Further advances in the predictive understanding of how cold regions’ critical zone processes, functions, and ecosystem services will continue to respond to climate warming and land use changes require multiscale monitoring technologies coupled with integrated observational and modeling tools. We highlight some of the major challenges, knowledge gaps, and opportunities in cold region critical zone research, with an emphasis on subsurface processes and responses in both natural and agricultural ecosystems.
Are virtual physiology laboratories effective for student learning? A systematic review
Authors: Zhang Xinyu , Al-Mekhled Dawoud , Choate Julia
Published: June 2021

It is unclear if the transition from traditional, in-person physiology laboratories to virtual alternatives has educational impacts on students. This study used a systematic review to critically evaluate research papers that investigated the effectiveness of virtual physiology laboratories for student learning. Eleven studies, retrieved from the Education Resources Information Center (ERIC) and Ovid MEDLINE databases, were selected for inclusion in this review, based on predetermined eligibility criteria. Subsequently, the studies went through a power analysis for potential biases before their results were synthesized and analyzed. This systematic review found that virtual physiology laboratories are effective for students’ learning of concepts. However, it was inconclusive as to whether virtual physiology laboratories are effective for students’ motivation for learning and learning of technical skills. It was found that blended models of virtual laboratories are at least as effective as in-person laboratories for conceptual learning. Overall, this systematic review provides useful insights for educators regarding the educational impacts of implementing virtual laboratories into the physiology curriculum and suggests research models for future evaluation of virtual laboratories.
A multiscale model of vascular function in chronic thromboembolic pulmonary hypertension
Authors: Colebank Mitchel J. , Qureshi M. Umar , Rajagopal Sudarshan , Krasuski Richard A. , Olufsen Mette S.
Published: June 2021

This article presents novel computational framework for predicting pulmonary hemodynamics in chronic thromboembolic pulmonary hypertension. The mathematical model is used to identify the optimal target lesions for balloon pulmonary angioplasty, combining simulated pulmonary artery pressure, wave intensity analysis, and a new quantitative metric of flow heterogeneity.
On the Norms of RFMLR-Circulant Matrices with the Exponential and Trigonometric Functions
Authors: Shi Baijuan
Published: June 2021

In this paper, based on combinatorial methods and the structure of RFMLR-circulant matrices, we study the spectral norms of RFMLR-circulant matrices involving exponential forms and trigonometric functions. Firstly, we give some properties of exponential forms and trigonometric functions. Furthermore, we study Frobenius norms, the lower and upper bounds for the spectral norms of RFMLR-circulant matrices involving exponential forms and trigonometric functions by some ingenious algebra methods, and then we obtain new refined results.
Survival Outcomes of Nonsmall Cell Lung Cancer Patients Treated with Afatinib Who Are Affected by Early Adverse Events
Authors: Logan Jessica M. , Brooks Doug A. , Rowland Andrew , Sorich Michael J. , Hopkins Ashley M.
Published: June 2021

Introduction. Afatinib is a first-line treatment option for patients with an advanced nonsmall cell lung cancer (NSCLC) expressing an epidermal growth factor receptor (EGFR) activating mutation. This study aimed to evaluate the association between early adverse events induced by afatinib and overall survival (OS) and progression free survival (PFS) in patients with advanced NSCLC. Methods. The study was a pooled post hoc analysis of the randomized trials LUX-Lung 3 and LUX-Lung 6 which evaluated afatinib versus pemetrexed-cisplatin or gemcitabine-cisplatin, respectively. Cox proportional hazard analysis was used to assess the impact of adverse events occurring within the first 28 days of afatinib therapy on the PFS and OS outcomes in treatment-naïve advanced NSCLC patients harbouring an EGFR activating mutation. Results. There were 468 patients who initiated first-line afatinib therapy within LUX-Lung 3 and LUX-Lung 6. A significant association between early rash and improved OS (hazard ratio (HR 95% CI); grade 1 = 0.74 [0.56–0.97]; grade 2+ = 0.64 [0.46–0.89]) (

P

 = 0.018) was observed, although no significant association with PFS was present (

P

 = 0.732). A significant association was identified between early diarrhoea and improved PFS (grade 1 = 0.83 [0.62–1.12]; grade 2+ = 0.62 [0.44–0.88]) (

P

 = 0. 015), although no significant association with OS was present (

P

 = 0.605). No associations between early stomatitis or paronychia and OS or PFS were identified. Conclusion. Rash occurring early after the initiation of afatinib was significantly associated with improved OS, an indicator that rash may be a surrogate of patients likely to achieve long-term survival. Consideration of using rash as a dose adjustment target may be warranted for future prospective trials aiming to optimise outcomes with afatinib therapy.
Amino-Functionalized Wood Aerogel for Efficient Removal of Copper Ions from Water
Authors: Meng Junwang , Guan Hao , Dai Xinjian , Wang Xiaoqing
Published: June 2021

Developing bio-based adsorbents for efficient removal of heavy metal ions from water has attracted increasing attention due to their abundance, low cost, and sustainability. However, most of these adsorbents are in powdered or granular forms, suffering from difficult regeneration and poor recyclability. Here, we report a highly porous three-dimensional amino-functionalized wood aerogel for efficient heavy metal adsorption. The amino-functionalized wood aerogel was prepared from natural balsa wood via a delignification treatment, followed by TEMPO-mediated oxidation of the delignified wood and then grafting polyethylenimine (PEI) onto the oxidized cellulose skeleton. The obtained amino-functionalized wood aerogel possessed a unique porous lamellar structure with a low bulk density of 77.2 mg/cm3 and high porosity of 94.9%. Benefiting from its high porosity and the introduced amino groups on the cellulose skeleton, the amino-functionalized wood aerogel exhibited a maximum Cu(II) adsorption capacity of 59.8 mg·g−1, which was significantly higher than those of the TEMPO-oxidized wood aerogel and natural balsa wood. The adsorption process can be well described by the pseudo-second-order and Langmuir isotherm models, indicating that the Cu(II) adsorption by the PEI@wood aerogel was dominated by a monolayer chemisorption process. The developed amino-functionalized wood aerogel provides new insights for the design of efficient and low-cost monolithic absorbents for heavy metal remediation.
Malyngamide F Possesses Anti-Inflammatory and Antinociceptive Activity in Rat Models of Inflammation
Authors: Li Zhuocheng , Zhang Lei , Zhao Zhichao
Published: June 2021

Objective. Inflammation and pain are involved in the pathophysiology of various clinical conditions. This investigation aims to probe the analgesic and anti-inflammatory activity of Maltoamide F. Methods. The possible toxicity of Maltoamide F was evaluated by an acute toxicity test. To assess the anti-inflammatory and antinociceptive effects of Maltoamide F on rats, the models of carrageenan-caused paw edema, xylene-induced ear edema, arachidonic-acid- (AA-) induced ear edema, formalin-caused plantar edema, and cotton-pellet-induced granuloma were established. Levels of TNF-α, PGE-2, and IL-6 were detected by enzyme-linked immunosorbent assay (ELISA). Results. Maltoamide F was safe at oral doses of 1–10 mg/kg for rats. Maltoamide F (1 mg/kg, 5 mg/kg, and 10 mg/kg) notably reduced carrageenan-induced edema percentage of paws in rats and decreased levels of PGE-2, IL-6, and TNF-α in homogenates of foot tissues. Maltoamide F (1 mg/kg, 5 mg/kg, and 10 mg/kg) reduced levels of PGE-2, IL-6, and TNF-α in foot tissues of formalin-induced rats. Maltoamide F (1 mg/kg, 5 mg/kg, and 10 mg/kg) repressed AA-induced increase of ear thickness in rats and reduced levels of PGE-2, IL-6, and TNF-α in homogenates of ear tissues. Maltoamide F (1 mg/kg, 5 mg/kg, and 10 mg/kg) reduced xylene-induced weight of ear edema in rats and reduced levels of PGE-2, IL-6, and TNF-α in homogenates of ear tissues. Maltoamide F (1 mg/kg, 5 mg/kg, and 10 mg/kg) reduced levels of PGE-2, IL-6, and TNF-α in homogenates of cotton ball granuloma of cotton-pellet-induced rats. Conclusions. Maltoamide F possessed anti-inflammatory and analgesic activity in inflammatory models of rats.
CLD-Net: A Network Combining CNN and LSTM for Internet Encrypted Traffic Classification
Authors: Hu Xinyi , Gu Chunxiang , Wei Fushan
Published: June 2021

The development of the Internet has led to the complexity of network encrypted traffic. Identifying the specific classes of network encryption traffic is an important part of maintaining information security. The traditional traffic classification based on machine learning largely requires expert experience. As an end-to-end model, deep neural networks can minimize human intervention. This paper proposes the CLD-Net model, which can effectively distinguish network encrypted traffic. By segmenting and recombining the packet payload of the raw flow, it can automatically extract the features related to the packet payload, and by changing the expression of the packet interval, it integrates the packet interval information into the model. We use the ability of Convolutional Neural Network (CNN) to distinguish image classes, learn and classify the grayscale images that the raw flow has been preprocessed into, and then use the effectiveness of Long Short-Term Memory (LSTM) network on time series data to further enhance the model’s ability to classify. Finally, through feature reduction, the high-dimensional features learned by the neural network are converted into 8 dimensions to distinguish 8 different classes of network encrypted traffic. In order to verify the effectiveness of the CLD-Net model, we use the ISCX public dataset to conduct experiments. The results show that our proposed model can distinguish whether the unknown network traffic uses Virtual Private Network (VPN) with an accuracy of 98% and can accurately identify the specific traffic (chats, audio, or file) of Facebook and Skype applications with an accuracy of 92.89%.
Stability and Bifurcation for a Delayed Diffusive Two‐Zooplankton One‐Phytoplankton Model with Two Different Functions
Authors: Meng Xin-You , Xiao Li
Published: June 2021

In this paper, a diffusion two‐phytoplankton one‐zooplankton model with time delay, Beddington–DeAnglis functional response, and Holling II functional response is proposed. First, the existence and local stability of all equilibria of such model are studied. Then, the existence of Hopf bifurcation of the corresponding model without diffusion is given by taking time delay as the bifurcation parameter. Next, the direction of Hopf bifurcation and the stability of the bifurcating periodic solutions are investigated by using the normal form theory and center manifold theorem. Furthermore, due to the local bifurcation theory of partial functional differential equations, Hopf bifurcation of the model is investigated by considering time delay as the bifurcation parameter. The explicit formulas to determine the properties of Hopf bifurcation are given by the method of the normal form theory and center manifold theorem for partial functional differential equations. Finally, some numerical simulations are performed to check out our theoretical results.