bluuebunny/crossref_metadata_2025 huggingface dataset:
2D boron nanosheet architectonics: opening new territories by smart functionalization
Authors: Han Chao , Han Rui , Zhang Xin , Xu Zhimei , Li Weijie , Yamauchi Yusuke , Huang Zhenguo
Published: January 2022

The lack of stability hinders the applications of pristine borophene. Functionalization imparts both stability and tunable properties allowing for wide application. This review focuses on the applications of functionalized 2D boron nanosheets.
Over 8% efficient CsSnI3-based mesoporous perovskite solar cells enabled by two-step thermal annealing and surface cationic coordination dual treatment
Authors: Ban Huaxia , Nakajima Takahito , Liu Zhirong , Yu Haixuan , Sun Qiang , Dai Letian , Shen Yan , Zhang Xiao-Li , Zhu Jun , Chen Peter , Wang Mingkui
Published: January 2022

Well-crystallized CsSnI3thin films can be easily obtained through two-step thermal annealing at low temperatures of 40 °C and 70 °C.
Electroluminescence and photocatalytic hydrogen evolution of S,N co-doped graphene oxide quantum dots
Authors: Cheng Tzu-Yang , Chou Feng-Pai , Huang Sheng-Cih , Chang Chin-Yuan , Wu Tung-Kung
Published: January 2022

S,N-GOQDs with stable electroluminescence, photoluminescence, and photocatalytic properties have been developed. They can be used as emitters for LED devices and as photocatalysts for hydrogen evolution in photo-electro-chemical energy conversion.
Thermodynamic guiding principles of high-capacity phase transformation materials for splitting H2O and CO2 by thermochemical looping
Authors: Zhai Shang , Nam Joonhyun , Sai Gautam Gopalakrishnan , Lim Kipil , Rojas Jimmy , Toney Michael F. , Carter Emily A. , Jung In-Ho , Chueh William C. , Majumdar Arun
Published: January 2022

In ferrite-based thermochemical looping, the maximum oxygen exchange capacity usually occurs at iron-poor compositions, even when iron is the redox active element. The underlying causes are uncovered by thermodynamic and phase diagram analyses.
Tunable luminescence of silver-exchanged SOD zeolite thermally treated under mild conditions
Authors: Tian Xinle , Li Qianrui , Yao Decui , Li Panlai , Li Huanrong , Wang Yige
Published: January 2022

Emission color shift and luminescence intensity enhancement of Ag-zeolite composites obtained by heat treatment under mild conditions were obtained by adjusting Ag+ and Cs+ contents. The composite has applicability in LED.
Frontier molecular orbital engineering in spiro-based molecules: achieving aggregation-induced delayed fluorescence for non-doped OLEDs
Authors: Li Xue , Shi Changshen , Mo Yuhang , Rao Jiancheng , Zhao Lei , Tian Hongkun , Sun Ning , Ding Junqiao
Published: January 2022

Different from spiro-blocking, frontier molecular orbital engineering has been proposed to develop AT-spiro-DMACF, which shows interesting aggregation-induced delayed fluorescence (AIDF) for non-doped OLEDs.
Molecular optimization of incorporating pyran fused acceptor–donor–acceptor type acceptors enables over 15% efficiency in organic solar cells
Authors: Wu Simin , Meng Lingxian , Zhang Zhe , Li Mingpeng , Yang Yang , Wang Jian , Chen Hongbin , Jiang Changzun , Wan Xiangjian , Li Chenxi , Yao Zhaoyang , Chen Yongsheng
Published: January 2022

Three acceptor–donor–acceptor type fused-ring non-fullerene acceptors of FOR-IN, FOR-1F and FOR-2F, were synthesized with the same pyran-composed backbone but different terminals, affording over 15% efficiency in organic solar cells.
Tyrosine-O-sulfation is a widespread affinity enhancer among thrombin interactors
Authors: Ripoll-Rozada Jorge , Maxwell Joshua W. C. , Payne Richard J. , Barbosa Pereira Pedro José
Published: January 2022

Tyrosine-O-sulfation is a common post-translational modification (PTM) of proteins following the cellular secretory pathway. First described in human fibrinogen, tyrosine-O-sulfation has long been associated with the modulation of protein–protein interactions in several physiological processes. A number of relevant interactions for hemostasis are largely dictated by this PTM, many of which involving the serine proteinase thrombin (FIIa), a central player in the blood-clotting cascade. Tyrosine sulfation is not limited to endogenous FIIa ligands and has also been found in hirudin, a well-known and potent thrombin inhibitor from the medicinal leech, Hirudo medicinalis. The discovery of hirudin led to successful clinical application of analogs of leech-inspired molecules, but also unveiled several other natural thrombin-directed anticoagulant molecules, many of which undergo tyrosine-O-sulfation. The presence of this PTM has been shown to enhance the anticoagulant properties of these peptides from a range of blood-feeding organisms, including ticks, mosquitos and flies. Interestingly, some of these molecules display mechanisms of action that mimic those of thrombin's bona fide substrates.
Role of macronutrient intake in the epigenetics of obesity
Authors: Patel Priyadarshni , Babu Jeganathan Ramesh , Wang Xu , Geetha Thangiah
Published: January 2022

Obesity is caused by a combination of hereditary and environmental factors. Despite extensive study, contemporary through diet, exercise, education, surgery, and pharmacological treatments, no effective long-term solution has been found to this epidemic. Over the last decade, there has been a tremendous advancement in understanding the science of epigenetics, as well as a rise in public interest in learning more about the influence of diet and lifestyle choices on the health of an individual. Without affecting the underlying DNA sequence, epigenetic alterations impact gene expression. Previous animal studies have shown a link between the type of diet and expression or suppression of obesity genes, but there are very few human studies that demonstrate the relationship between dietary intake and obesity gene expression. This review highlights the effects of carbohydrates, lipids, and protein intake from the diet on obesity-related genes.
Cholinergic blockade of neuroinflammation: from tissue to RNA regulators
Authors: Zorbaz Tamara , Madrer Nimrod , Soreq Hermona
Published: January 2022

Inflammatory stimuli and consequent pro-inflammatory immune responses may facilitate neurodegeneration and threaten survival following pathogen infection or trauma, but potential controllers preventing these risks are incompletely understood. Here, we argue that small RNA regulators of acetylcholine (ACh) signaling, including microRNAs (miRs) and transfer RNA fragments (tRFs) may tilt the balance between innate and adaptive immunity, avoid chronic inflammation and prevent the neuroinflammation-mediated exacerbation of many neurological diseases. While the restrictive permeability of the blood–brain barrier (BBB) protects the brain from peripheral immune events, this barrier can be disrupted by inflammation and is weakened with age. The consequently dysregulated balance between pro- and anti-inflammatory processes may modify the immune activities of brain microglia, astrocytes, perivascular macrophages, oligodendrocytes and dendritic cells, leading to neuronal damage. Notably, the vagus nerve mediates the peripheral cholinergic anti-inflammatory reflex and underlines the consistent control of body–brain inflammation by pro-inflammatory cytokines, which affect cholinergic functions; therefore, the disruption of this reflex can exacerbate cognitive impairments such as attention deficits and delirium. RNA regulators can contribute to re-balancing the cholinergic network and avoiding its chronic deterioration, and their activities may differ between men and women and/or wear off with age. This can lead to hypersensitivity of aged patients to inflammation and higher risks of neuroinflammation-driven cholinergic impairments such as delirium and dementia following COVID-19 infection. The age- and sex-driven differences in post-transcriptional RNA regulators of cholinergic elements may hence indicate new personalized therapeutic options for neuroinflammatory diseases.
Parent/Caregiver Views of the Effectiveness of Speech-Language Pathology for Children Born With Cleft Palate Delivered via Telemedicine During COVID-19
Authors: Southby Lucy , Harding Sam , Davies Amy , Lane Hannah , Chandler Hannah , Wren Yvonne
Published: January 2022

Purpose:

The purpose of this study was to describe and examine parent views of speech-language pathology (SLP) for children born with cleft palate delivered via telemedicine during the COVID-19 pandemic in the United Kingdom (UK).

Method:

Parents were asked whether they found this method of delivery “very effective,” “somewhat effective,” or “not at all effective.” Free text was then invited. There were 212 responses. Ordinal chi-square, Kruskal–Wallis, or Fisher's exact tests examined associations between parent views of effectiveness and biological variables and socioeconomic status. Free text responses were analyzed using qualitative content analysis.

Results:

One hundred and forty (66.0%) respondents reported that SLP delivered via telemedicine was “somewhat effective,” 56 (26.4%) “very effective,” and 16 (7.6%) “not at all effective.” There was no evidence of an association between parent reported effectiveness and any of the explanatory variables. Parent-reported challenges impacting on effectiveness included technology issues and keeping their children engaged with sessions. Importantly, telemedicine was viewed as “better than nothing.”

Conclusions:

Most parents reported that they felt SLP delivered via telemedicine during the first few months of the COVID-19 pandemic in the UK was at least “somewhat effective.” It is important to interpret this in the context of there being no other method of service delivery during this time and that this study only represents families who were able to access SLP delivered via telemedicine. Further work is needed to identify which children with cleft palate might benefit from SLP delivered via telemedicine to inform postpandemic service provision.
Focal learning on stranger for imbalanced image segmentation
Authors: Zhao Yaochi , Liu Shiguang , Hu Zhuhua
Published: January 2022

It is an open issue to train effective deep network models on class imbalance datasets. In the widely used cost‐sensitive imbalanced learning methods, the costs are based on the losses or class probabilities of samples. In this paper, it is discovered that these traditional cost‐sensitive methods discard the clustering feature, and introduce the errors of annotations into costs, leading to sub‐optimal models. It is further investigated that the feature magnitude of sample, which is computed before probability and loss, not only is independent of the annotation, but also represents the familiarity degree of model with the sample. These characteristics of feature magnitude are used to guide the training and inference of model. First, the concept of stranger is proposed, which is the sample with small feature magnitude value, and the idea of focal learning on strangers (FLS) is proposed. By adding the idea of FLS into two existing cost‐sensitive methods, two novel losses are put forward: instance‐level focal stranger loss (IFSL) and class‐level focal stranger loss (CFSL). The losses can improve the aggregation features of samples within class, and reduce the negative influences of annotation errors on imbalanced learning. Second, considering the large difference of feature magnitude means between minority class and majority class in case of extreme class‐imbalance dataset, a bias determination (BD) strategy is put forward to improve classification performance during inference. The methods are applied to the tasks of image semantic segmentation and salient‐instance segmentation. The experimental results on four public semantic segmentation datasets demonstrate that IFSL can reduce the over‐fitting of model, improve the classification accuracy of rare samples, and alleviate the reliance of performance on the annotation quality. The experimental results on two public salient‐instance segmentation datasets show that CFSL makes the model have better scoring ability for salient object. Besides, the BD strategy can reduce the wrong classification caused by bias model. Therefore, the proposed methods can significantly advance image segmentation.
The Role of Er-yag Glass Laser in Skin Resurfacing
Authors: Bertossi Dario , Carletta Luca C. , Fink Laetitia Colombo , Bartolucci Marco , Barba Gianfranco , Montanari Alessia , Alotto Massimo , Brusi Claudio , Chirumbolo Salvatore
Published: January 2022

Following our survey, we can appreciate that a variety of laser platforms exist to rejuvenate the skin by resurfacing the outer layer of the skin as well as heating the lower layers of the dermis. Based on reliable clinical effectiveness and a limited side effect profile, we can confirm that nonablative fractionated technologies greatly improve the appearance of lentigines, rhytids; eliminate sun damage, attenuate scarring due to acne and other causes; and treat hyperpigmentation. The Fraxel (Solta Medical) laser system delivers pulses across a wide range of density and energy levels. We determined that when increasing the pulse energy this led to an increase in thermolysis microzone depth and width without damaging the surrounding tissue. Due to its performance and various clinical applications, Fraxel laser can be optimally considered to be the gold standard for skin rejuvenation
Puzzle Facelift: A Nonsurgical, Whole Treatment for Facial Modeling and Rejuvenation
Authors: Bertossi Dario , Nocini Riccardo , Chirumbolo Salvatore , Kapoor Krishan Mohan
Published: January 2022

The assessment of correct anatomy of face and the evaluation of the dynamic interplay between anatomy and function, to get an overall improvement, is a leading topic in aesthetic surgery and has increased its impact in recent years. A nonsurgical impact technique reduces both post-treatment discomfort and the overall cost. Obtaining the simultaneous correction in forehead, nose, lips, and chin means obtaining an overall improvement in face view. Likewise, the high predictability of the procedure and the absence of alloplastic implant, bone re-absorption, and scars have to be considered in nonsurgical aesthetic medicine. In conclusion, a single session of profile correction using hyaluronic acid filler should be proposed to patients, every time the aesthetic practitioner sees a coexistence of forehead, nose lips, and chin defects.
Mechanochemical Synthesis of Diarylethynes from Aryl Iodides and CaC2
Authors: Bolm Carsten , van Bonn Pit
Published: January 2022

A mechanochemical synthesis of diarylethynes from aryl iodides and calcium carbide as acetylene source is reported. The reaction is catalyzed by a palladium catalyst in the presence of copper salt, base, and ethanol as liquid assisting grinding (LAG) additive. Various aryl and heteroaryl iodides have been converted in up to excellent yields.
Marginal Zone B-cell Lymphoma of the Gasserian Ganglion: Case Report and Review of the Literature
Authors: Hegazy Ahmed , Al-Shami Hieder , Arundhatai Biswas , Fathy Mohammed , Salah Ahmed M. , Aboul-Ela Hashem , Alsawy Mohamed F.M. , Elkatatny Amr Mostafa
Published: January 2022

Primary central nervous system lymphoma (PCNSL) is a rare subtype of extranodal non-Hodgkin's lymphoma that accounts for 4% of newly diagnosed central nervous system (CNS) tumors. Most primary lymphomas of the central nervous system are of the subtype of diffuse large B-cell lymphomas, which have highly aggressive behavior and may involve the brain, leptomeninges, eyes or spinal cord without evidence of systemic disease. Primary CNS lymphomas are very rare in immunocompetent patients, but their rates are increasing. So far, only 11 primary Gasser ganglion lymphomas have been reported, with an incidence of 2.5 cases per 30,000,000 inhabitants. However, B cell lymphomas of the marginal zone of the Gasserian ganglion have been very rarely reported. We report here a clinical presentation characteristic of B cell lymphoma of the marginal zone of the Gasser ganglion in an immunocompetent patient who was treated with surgery and radiotherapy, evolving with improvement of symptoms and without recurrence in 3 months of follow-up.
Surgical Treatment for Refractory Aggression after Bacterial Meningitis Complicated by Stroke: Case Report
Authors: Vaccario Pietro Alessandro , Rocha Alícia Carolina Rodrigues , Silva Ledismar José da
Published: January 2022

Bacterial meningitis remains a public health problem. One of the complications of this group of diseases is cerebral ischemia, an important indicator of severity and an independent predictor of poor prognosis. It is already known that, in many cases, pathological aggressiveness is the result of brain abnormalities in individuals with mental illnesses. The indication of neurosurgeries for psychiatric disorders (NPDs) relies on numerous studies based on scientific evidence that correlate psychiatric illnesses with the limbic system and the pathophysiology of emotions. The development of sophisticated stereotactic target localization techniques, brain atlases, and imaging methods made stereotaxis possible, a procedure that increased the precision of neurosurgery and reduced brain damage. Nowadays, multiple targets can be treated during NPD, according to the particular characteristics of the patient. Moreover, the combination of lesions leads to more significant improvements compared with isolated procedures. The present study aimed to report the rare case of a patient with a history of bacterial meningitis who developed stroke and chronic pathological aggressiveness refractory to clinical treatment and underwent ablation using the multitarget stereotactic technique.
Plasma Homocysteine in Behcet's Disease: A Systematic Review and Meta-Analysis
Authors: Merashli Mira , Bucci Tommaso , Pastori Daniele , Pignatelli Pasquale , Arcaro Alessia , Gentile Fabrizio , Marottoli Vincenzo , Ames Paul R. J.
Published: January 2022

Aim To evaluate the relevance of plasma homocysteine (HC) in Behcet's disease (BD) and its clinical manifestations.

Methods Systematic review of EMBASE and PubMed databases according to PRISMA guidelines from inception to July 2021; random-effects meta-analyses for continuous outcomes.

Results The search strategy retrieved 48 case–control (2,669 BD and 2,245 control participants) and 5 cohort studies (708 BD participants). Plasma HC was higher in BD than in controls (p < 0.0001) with wide heterogeneity (I2
 = 89.7%) that remained unchanged after sensitivity analysis according to year of article publication, age of BD participants, study size, study quality, method of HC determination, and male/female ratio >1.5; some pooled ethnicities explained a small part of the heterogeneity (I2
 = 16.3%). Active BD participants had higher HC than inactive ones (p < 0.0001), with moderate heterogeneity (I2
 = 49.2%) that disappeared after removal of an outlier study with very high disease activity. BD participants with any vascular involvement had higher HC than those without (p < 0.0001) with wide heterogeneity (I2
 = 89.7%); subgroup analysis on venous thrombosis only changed neither effect size (p < 0.0001) nor heterogeneity (I2
 = 72.7%). BD participants with ocular involvement had higher HC than those without (p < 0.0001) with moderate heterogeneity (I2
 = 40.3%).

Conclusion Although causality cannot be inferred, the consistency of the elevation of plasma HC in BD, particularly in patients with active disease, with vascular and ocular involvement suggests an intrinsic involvement of HC in these clinical manifestations.
The Utilization of MS-MLPA as the First-Line Test for the Diagnosis of Prader–Willi Syndrome in Thai Patients
Authors: Prapasrat Chanita , Onsod Preyaporn , Korkiatsakul Veerawat , Rerkamnuaychoke Budsaba , Wattanasirichaigoon Duangrurdee , Chareonsirisuthigul Takol
Published: January 2022

Prader–Willi syndrome (PWS) is a genetic disorder caused by the expression disruption of genes on the paternally inherited allele of chromosome 15q11.2-q13. Apart from clinical diagnostic criteria, PWS is confirmed by genetic testing. Methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) is one of the molecular techniques used to analyze this syndrome. This study aimed to evaluate the concordance of the test results of MS-MLPA with conventional techniques in the diagnosis of PWS in Thai patients. Forty leftover specimens from routine genetic testing (MS-PCR and FISH) were tested to obtain MS-MLPA results. By comparison, perfect concordance was shown between the result of MS-MLPA and those of conventional techniques. In conclusion, MS-MLPA is an accurate and cost-effective assay that can be used to confirm PWS diagnosis with explicit deletion of affected genes.
Prevalence of Inherited Procoagulant States in Cerebral Venous Thrombosis and its Correlation with Severity and Outcome
Authors: Gill Shaman , Dhull Pawan , Bhardwaj Madhukar
Published: January 2022

BackgroundCerebral venous thrombosis (CVT) is one of the important causes of stroke in young adults. It is caused by complete or partial thrombotic occlusion of the cerebral venous sinuses or cortical veins. There are many risk factors associated with this condition, out of which common ones are oral contraceptives use, genetic, or acquired thrombophilias, infections, malignancy, pregnancy, and puerperium. We aimed to study the prevalence of inherited procoagulant states in patients with CVT and correlate these states with the severity and outcome.

Materials and Methods It was a prospective observational study of 2 years duration in which 75 patients, 18 to 50 years old, with confirmed CVT were included. The baseline data, imaging findings were recorded for all the patients. After 3 months of the onset of CVT, anticoagulants were stopped and a procoagulant test was done for all patients. Severity was assessed by Glasgow Coma Score (GCS) at the onset of illness. Functional assessments were done using the modified Rankin Scale (mRS) at presentation, at 7 days, 6 weeks, and 3 months.

Results In the present study, any procoagulant state was seen in 9 out of 75 patients with CVT that accounted for 12% of the total population. There was no significant correlation between the presence of procoagulant states and severity of illness as assessed by GCS at presentation. The presence of any thrombophilia did not affect the final outcome at 7 days, 6 weeks or 3 months (p = 0.532,p = 0.944 andp = 0.965 respectively) as assessed by modified Rankin Scale (mRS).

Conclusion Inherited procoagulant states are an important risk factor for CVT. The presence of an inherited procoagulant state does not have any correlation with the disease severity and outcome.
Addressing Adolescent Relationship Abuse in the Context of Reproductive Health Care
Authors: Ragavan Maya I. , Barral Romina L. , Randell Kimberly A.
Published: January 2022

Adolescent relationship abuse (ARA) is a significant public health issue that includes physical, sexual, psychological and cyber abuse, reproductive coercion, and/or sexual exploitation within an intimate relationship in which one or both partners is a minor. ARA is associated with numerous negative outcomes that include all domains of health. Many negative outcomes of ARA are related to reproductive and sexual health (RSH); thus, reproductive health care providers must be equipped to recognize and address ARA. This article will review the epidemiology and outcomes of ARA, followed by a discussion of means to robustly address ARA in health care settings. We recommend a strengths-based approach that promotes healthy adolescent relationships, connects adolescents experiencing ARA to harm reduction resources, and equips adolescents to serve as a resource for their peers.
The price of prosociality in pandemic times
Authors: Santamaría-García Hernando , Burgaleta Miguel , Legaz Agustina , Flichtentrei Daniel , Córdoba-Delgado Mateo , Molina-Paredes Juliana , Linares-Puerta Juliana , Montealegre-Gómez Juan , Castelblanco Sandra , Schulte Michael , Páramo Juan David , Mondragon Izara , Leongómez Juan David , Salamone Paula , González-Pacheco Juan , Báez Sandra , Eyre Harris , Ibanez Agustín
Published: January 2022

The SARS-CoV-2 pandemic has imposed widespread negative impacts (economically, psychologically, neurologically, and societally), and has changed daily behaviors on a global scale. Such impacts are more significant and pervasive in countries with higher levels of inequality and reduced Government capacity and responsiveness, such as those in the Global South (e.g., Colombia). Differences in social and moral cognitive skills may significantly impact individual attitudes and responses to the pandemic. Here, we aimed to assess the extent to which factors associated with prosociality (including empathy, theory of mind (ToM), and moral judgments) predict the perception of SARS-CoV-2 impacts and responses. Participants (N = 413) from Colombia answered factors associated with prosociality measures and judgments about SARS-CoV-2 risk, impact, and acceptance of quarantine guidelines. Results revealed that affective empathy (personal distress and empathic concern) and moral tendencies (deontological trends) predicted greater acceptance of quarantine but in turn yielded an increased perception of risks and individual impacts of SARS-CoV-2. Moreover, age (older) and gender (female) also increased the risk perception and impact estimation. These results underscore the role of prosocial-related predispositions informing individual responses to the pandemic and provide an opportunity to exploit this knowledge to inform successful interventions favoring behavioral change.
Accelerated simulation method for charge regulation effects
Authors: Curk Tine , Yuan Jiaxing , Luijten Erik
Published: January 2022

The net charge of solvated entities, ranging from polyelectrolytes and biomolecules to charged nanoparticles and membranes, depends on the local dissociation equilibrium of individual ionizable groups. Incorporation of this phenomenon, charge regulation (CR), in theoretical and computational models requires dynamic, configuration-dependent recalculation of surface charges and is therefore typically approximated by assuming constant net charge on particles. Various computational methods exist that address this. We present an alternative, particularly efficient CR Monte Carlo method (CR-MC), which explicitly models the redistribution of individual charges and accurately samples the correct grand-canonical charge distribution. In addition, we provide an open-source implementation in the large-scale Atomic/Molecular Massively Parallel Simulator molecular dynamics (MD) simulation package, resulting in a hybrid MD/CR-MC simulation method. This implementation is designed to handle a wide range of implicit-solvent systems that model discreet ionizable groups or surface sites. The computational cost of the method scales linearly with the number of ionizable groups, thereby allowing accurate simulations of systems containing thousands of individual ionizable sites. By matter of illustration, we use the CR-MC method to quantify the effects of CR on the nature of the polyelectrolyte coil–globule transition and on the effective interaction between oppositely charged nanoparticles.
Direct writing of divacancy centers in silicon carbide by femtosecond laser irradiation and subsequent thermal annealing
Authors: Almutairi A. F. M. , Partridge J. G. , Xu Chenglong , Cole I. S. , Holland A. S.
Published: January 2022

Divacancy (VSiVC) centers in silicon carbide (SiC) have potential applications in quantum communication and sensing due to their attractive optical and spin properties. To realize many of these divacancy-based quantum applications, it is vital that they are created in prescribed locations with high accuracy. Here, we describe the production of arrays of divacancy centers in 4H polytype SiC (4H-SiC) by femtosecond laser irradiation and subsequent thermal annealing. We optically characterized these divacancy centers by photoluminescence (PL) confocal mapping using a custom-built confocal microscope. The created divacancy centers show a bright stable emission that depends on the pulse energy of the femtosecond laser. PL spectra of the divacancy centers were collected using micro-Raman spectroscopy at the low temperature of 4.2 K and room temperature. The effect of thermal annealing was studied at various temperatures from 500 °C to 1000 °C and showed that the maximum divacancy center PL intensity was achieved at 800 °C. These and the aforementioned measurements show that the femtosecond laser writing method enables divacancy centers to be accurately positioned in 4H-SiC.
Spectral analysis of Dirac operators with delta interactions supported on the boundaries of rough domains
Authors: Benhellal Badreddine
Published: January 2022

Given an open set Ω⊂R3, we deal with the spectral study of Dirac operators of the form Ha,τ = H + Aa,τδ∂Ω, where H is the free Dirac operator in R3 and Aa,τ is a bounded, invertible, and self-adjoint operator in L2(∂Ω)4, depending on parameters (a,τ)∈R×Rn, n ⩾ 1. We investigate the self-adjointness and the related spectral properties of Ha,τ, such as the phenomenon of confinement and the Sobolev regularity of the domain in different situations. Our set of techniques, which is based on the use of fundamental solutions and layer potentials, allows us to tackle the above problems under mild geometric measure theoretic assumptions on Ω.
Low-frequency shock train oscillation control in a constant area duct
Authors: Petha Sethuraman Vignesh Ram , Yang Yosheph , Kim Jae Gang
Published: January 2022

The self-excited shock train oscillation control using partial removal of boundary layer flow in a constant area duct is studied numerically using unsteady Reynolds Averaged Navier–Stokes simulation. The effect of varying the suction flow ratio on the shock train oscillatory characteristics is analyzed using steady and unsteady statistics, space–time contour, power spectra, and cross correlation analysis. For the present study, a constant area duct of height 0.032 mm, and the aspect ratio of 25, at freestream Mach number of 2.0 and back pressure ratio of 0.52 is considered. The removal of the boundary layer through an angled suction slot with three different suction flow ratios is performed. Numerical results indicate that the removal boundary layer restricts the bifurcation process of the shock train and appears to be a single curved normal shock at a higher suction flow ratio. Also, the transition of regular reflection to the Mach reflection type is noted. The suction flow from the top and bottom slot tends to initiate a lateral oscillation that forms a wavy mixing flow region. The power spectral density contour suggests that the increase in suction flow ratio will tend to increase the dominant frequency ranges from (0.034 to 0.094). The cross correlation indicates the presence of downstream pressure disturbance that moves toward the upstream direction. With suction flow, a disturbance that emerges from the suction slot moves in the opposite direction and dominates at a lower suction flow ratio and these disturbances disappear at a large suction flow ratio.
Continuous-wave operation of electrically driven single mode microlaser
Authors: Tang Kai , Wan Peng , Kan Caixia , Liu Maosheng , Shi Daning , Jiang Mingming
Published: January 2022

Developing current-driven single-mode micro-/nanolasers is highly desirable for various practical applications, but still faces severe challenges. Herein, a continuous-wave operation of an electrically driven laser device using a Ga-incorporated n-type ZnO microwire, MgO nanofilm, and p-type GaAs substrate is demonstrated. The device can enable a single-mode lasing peaking at 820 nm and a narrow linewidth of about 0.4 nm, and the quality factor Q is evaluated to 2000. The presence of a distinct threshold, sharp linewidth reduction, and polarized coherent illumination provides conclusive evidence for achieving lasing oscillation. Relative polaritonic features are further proofed; thus, single-mode lasing feature should be ascribed to the exciton–polariton. The results can enable a workable avenue to realize near-infrared micro-/nanolaser diodes for high-efficiency coherent light sources, which are no longer limited by conventional narrow-bandgap semiconductors.
Improved well-balanced free-energy lattice Boltzmann model for two-phase flow with high Reynolds number and large viscosity ratio
Authors: Zhang Chunhua , Guo Zhaoli , Wang Lian-Ping
Published: January 2022

Spurious velocities and inaccurate density properties arising from the imbalance of discretized forces at discrete level are frequently observed in numerical simulation of multiphase flows based on lattice Boltzmann equation (LBE) models. In this paper, an improved well-balanced free-energy LBE model is proposed for two phase flows with high Reynolds numbers and large viscosity differences based on the well-balanced LBE [Guo et al., Phys. Fluids 33, 031709 (2021)]. To this end, a free parameter associated with the shear rate is introduced into the equilibrium distribution function. This results in a fluid viscosity that is dependent not only on the relaxation time but also on the introduced parameter. The relaxation time can be chosen to improve the numerical stability and accuracy, while the viscosity is mainly determined by the new parameter. To test the capability of the present model in capturing discrete equilibrium states, both one-dimensional flat interface and two-dimensional stationary droplet are simulated. Numerical results show that the present model is capable of eliminating spurious velocities and maintaining a constant chemical potential when the system reaches an equilibrium state. To further validate the performance of the present LBE for dynamic problems, both binary droplet collision and single bubble rising are performed, which demonstrates that the present model has the capability to deal with two phase flows with high Reynolds number and large viscosity ratio.
Electron magnetosonic waves and sub-ion magnetic holes in the magnetotail plasma
Authors: Shustov P. I. , Artemyev A. V. , Volokitin A. S. , Vasko I. Y. , Zhang X.-J. , Petrukovich A. A.
Published: January 2022

Recent observations of hot plasma in Earth's magnetotail and magnetosheath demonstrate nonlinear sub-ion scale magnetic holes, spatially localized dips of magnetic field intensity. These structures resemble magnetosonic solitary waves, but do not include any significant density perturbations. Instead, the magnetic field depression is balanced by hot electron pressure. This study aims to investigate linear modes of hot plasma with two electron components, hot and cold, to find a mode sharing properties (propagation direction, velocity, polarization and density/temperature perturbations) of observed sub-ion scale magnetic holes. The linear analysis of three-component plasma (ions, hot and cold electrons) shows an electromagnetic mode with slow, nearly cross field propagation and absence of density perturbations. Compressional perturbations of the magnetic field in this mode are balanced by hot electron pressure perturbations. This mode resembles the electron acoustic mode with cross field propagation in hot plasma with a significant magnetic field perturbation and can be called electron magnetosonic mode. We discuss properties of this mode in comparison with spacecraft observations.
A methodology for modeling the interaction between turbulence and non-linearity of the equation of state
Authors: Poormahmood A. , Salehi M. Mahdi , Farshchi M.
Published: January 2022

Computational fluid dynamics simulation of turbulent mixing layers with significant density variations may require a closure model for the interaction between the unresolved turbulence scales and the equation of state (EoS). Ideal gas flows with significant temperature variations and real gas flows near the critical pressure and temperature undergo non-linear density variations. Therefore, using the first moment closure to obtain the mean/filtered density field from the EoS in a pressure-based computational fluid dynamics approach may result in significant modeling errors. In this work, a methodology is formulated to determine whether or not a closure model is required in the context of low-Mach number mixing layers. The methodology is based on a presumed probability density function closure modeling approach to develop a regime diagram in terms of four non-dimensional variables: reduced pressure, normalized lower temperature, temperature ratio across the mixing layer, and normalized variance of temperature fluctuations. The regime diagram clearly outlines conditions requiring no closure model and is approximately universal for different working fluids in a mixing layer. A posteriori simulations of a turbulent jet flow at different thermodynamic conditions show that the regime diagram effectively determines the necessity of closure modeling for density.
Coupling analysis of transient aerodynamic and dynamic response of articulated heavy vehicles under crosswinds
Authors: Zhang Qianwen , Su Chuqi , Tsubokura Makoto , Hu Zhen , Wang Yiping
Published: January 2022

Vehicle aerodynamics and dynamics in gusty crosswind conditions are of increasing significance for the lateral stability of heavy ground vehicles, especially articulated heavy vehicles (AHVs). The unsteady aerodynamic loads acting on AHVs can greatly exceed loads of a single-vehicle unit; these may deteriorate the lateral stability and lead to a loss of handling control. In this study, the time characteristics of aerodynamic loads and dynamic response of a tractor semi-trailer were considered, based on simulating the relative motions of these two components to reproduce actual scenarios of AHVs in crosswinds. A dynamic fully coupled method was developed and adopted to realize a real-time data exchange of flow fields and multi-bodies. Two multi-body systems (for non-articulated heavy vehicles and AHVs, respectively) were created to study the influences of the relative motions on the aerodynamic performance and lateral stability of the vehicles. The Reynolds-averaged Navier–Stokes (RANS) method and renormalization group (RNG) k−ε equation were adopted to account for the turbulence. A wind tunnel experiment was conducted to validate the numerical method. The results show that AHVs are more sensitive to the crosswind, with significant differences in the magnitudes and directions of the aerodynamic forces, moments, dynamic yaw angle, and lateral displacement. Three different wind types were considered (step, linear, and sinusoidal). The step crosswind produces the largest average lateral force and yawing moment, resulting in the largest lateral displacement and yaw angle. The largest hitch angle is found for linear gusts, presenting the highest safety risks in regard to jackknifing and trailer swings.
Thermodynamically admissible 13-moment equations
Authors: Struchtrup Henning , Öttinger Hans Christian
Published: January 2022

Grad's 13-moment equations describe transport in mildly rarefied gases well, but are not properly embedded into nonequilibrium thermodynamics since they are not accompanied by a formulation of the second law. In this work, the Grad-13 equations are embedded into the framework of GENERIC (general equation for the nonequilibrium reversible–irreversible coupling), which demands additional contributions in the equations to guarantee thermodynamic structure. As GENERIC building blocks, we use a Poisson matrix for the basic convection behavior and antisymmetric friction matrices to correct for additional convective transport terms. The ensuing GENERIC-13 equations completely match the Grad-13 equations up to second-order terms in the Knudsen number and fulfill all thermodynamic requirements.
Sizes of pure and doped helium droplets from single shot x-ray imaging
Authors: Tanyag Rico Mayro P. , Bacellar Camila , Pang Weiwu , Bernando Charles , Gomez Luis F. , Jones Curtis F. , Ferguson Ken R. , Kwok Justin , Anielski Denis , Belkacem Ali , Boll Rebecca , Bozek John , Carron Sebastian , Chen Gang , Delmas Tjark , Englert Lars , Epp Sascha W. , Erk Benjamin , Foucar Lutz , Hartmann Robert , Hexemer Alexander , Huth Martin , Leone Stephen R. , Ma Jonathan H. , Marchesini Stefano , Neumark Daniel M. , Poon Billy K. , Prell James , Rolles Daniel , Rudek Benedikt , Rudenko Artem , Seifrid Martin , Swiggers Michele , Ullrich Joachim , Weise Fabian , Zwart Petrus , Bostedt Christoph , Gessner Oliver , Vilesov Andrey F.
Published: January 2022

Advancements in x-ray free-electron lasers on producing ultrashort, ultrabright, and coherent x-ray pulses enable single-shot imaging of fragile nanostructures, such as superfluid helium droplets. This imaging technique gives unique access to the sizes and shapes of individual droplets. In the past, such droplet characteristics have only been indirectly inferred by ensemble averaging techniques. Here, we report on the size distributions of both pure and doped droplets collected from single-shot x-ray imaging and produced from the free-jet expansion of helium through a 5 μm diameter nozzle at 20 bars and nozzle temperatures ranging from 4.2 to 9 K. This work extends the measurement of large helium nanodroplets containing 109–1011 atoms, which are shown to follow an exponential size distribution. Additionally, we demonstrate that the size distributions of the doped droplets follow those of the pure droplets at the same stagnation condition but with smaller average sizes.
Seed-applied zinc-solubilising
Authors: Mumtaz Muhammad Zahid , Ahmad Maqshoof , Zafar-ul-Hye Muhammad , Saqib Muhammad , Akhtar Muhammad Fakhar U Zaman , Zaheer Muhammad Saqlain
Published: January 2022

Biofertiliser is considered a promising biofortification intervention that can integrate with plant breeding as well as agronomic measures to overcome malnutrition in regions where the staple diet is cereal. This study was conducted to improve maize (Zea mays L.) productivity and biofortification with zinc (Zn) through the application of Zn-solubilising biofertilisers. Four pre-isolated, promising Zn-solubilising Bacillus strains, Bacillus sp. ZM20, B. aryabhattai ZM31, B. aryabhattai S10 and B. subtilis ZM63, were coated on maize seeds by forming slurry-based sole- and co-inoculated biofertilisers. The treated maize seeds were grown in a spring season (Trial I) and the experiment was repeated the following year on the same field (Trial II). The seed-applied co-inoculated Bacillus biofertiliser formulations significantly promoted antioxidant enzyme activities (ascorbate peroxidase, peroxidase and superoxide dismutase), growth and yield attributes, and nutrient accumulation in maize grains during both field trials compared with sole-inoculated biofertiliser formulations. Application of ZM31–ZM63 biofertiliser formulation showed a greater increase in these attributes than other biofertiliser formulations, as well as an increase in grain iron (Fe) concentration (up to 1.69-fold in Trial I and 1.77-fold in Trial II) and Zn concentration (up to 1.50-fold in Trial I and 1.41-fold in Trial II) relative to the uninoculated control. Fe and Zn concentrations in maize grains resulting from the application of seed-based Bacillus biofertiliser formulations could fulfill the minimum required level of these nutrients for daily intake. From the study, recommendation can be made to apply Zn-solubilising bioinoculants for the biofortification of maize grains to overcome malnutrition issues in regions with cereal-based staple diets.
Invariant odor recognition with ON–OFF neural ensembles
Authors: Nizampatnam Srinath , Zhang Lijun , Chandak Rishabh , Li James , Raman Baranidharan
Published: January 2022

Significance

The smell of coffee is the same whether it is smelled in a coffee shop or grocery shop (different backgrounds), on a hot day or a cold day (different ambient conditions), after lunch or dinner (different temporal contexts), or using a deep inhalation or normal inhalation (different stimulus dynamics). This feat of pattern recognition that is still difficult to achieve in artificial chemical sensing systems is performed by most sensory systems for their survival. How is this capability achieved? We explored this issue. We found that there are two orthogonal ensembles of neurons, one activated during stimulus presence (ON neurons) and one activated after its termination (OFF neurons), and both contribute to this important computation in a complementary fashion.
Structural transitions in the GTP cap visualized by cryo-electron microscopy of catalytically inactive microtubules
Authors: LaFrance Benjamin J. , Roostalu Johanna , Henkin Gil , Greber Basil J. , Zhang Rui , Normanno Davide , McCollum Chloe O. , Surrey Thomas , Nogales Eva
Published: January 2022

Significance

Microtubules (MTs) are nonequilibrium polymers that switch between states of growth and shrinkage. This property is critical for their function and is a consequence of GTP hydrolysis in the MT. The structure of the stable GTP part of the MT (the GTP cap) has previously been inferred from MTs polymerized with nonhydrolyzable GTP analogs. Here, we report high-resolution structures of MTs truly containing GTP, polymerized from mutated, hydrolysis-deficient tubulins. We find that GTP-MTs have an “expanded lattice” and a “closed seam,” structural characteristics possibly responsible for stabilizing the GTP cap. These results provide insight into the structural transitions at growing MT ends, furthering our understanding of the bistable nature of MTs.
Photosynthetic assimilation of CO
2
regulates TOR activity
Authors: Mallén-Ponce Manuel J. , Pérez-Pérez María Esther , Crespo José L.
Published: January 2022

Significance

Photosynthetic organisms are responsible for the incorporation of inorganic carbon in the biosphere through a fundamental process known as carbon fixation. This reaction allows the reduction of inorganic carbon, mostly atmospheric CO
2
, to organic compounds such as carbohydrates and amino acids. Despite the biological relevance of carbon fixation in nature, how photosynthetic cells sense carbon availability remains poorly understood. Using the model microalga
Chlamydomonas reinhardtii
, we found that the photosynthetic assimilation of CO
2
regulates the activity of the target of rapamycin (TOR) kinase, a master regulator of cell growth and nutrient sensor widely conserved in all eukaryotes. Our study revealed that inorganic carbon fixation and photosynthesis regulate TOR activity, likely through the synthesis of central amino acids in carbon metabolism.
Recruitment of an ancient branching program to suppress carpel development in maize flowers
Authors: Klein Harry , Gallagher Joseph , Demesa-Arevalo Edgar , Abraham-Juárez María Jazmín , Heeney Michelle , Feil Regina , Lunn John E. , Xiao Yuguo , Chuck George , Whipple Clinton , Jackson David , Bartlett Madelaine
Published: January 2022

Significance

Floral morphology is immensely diverse. One developmental process acting to shape this diversity is growth suppression. For example, grass flowers exhibit extreme diversity in floral sexuality, arising through differential suppression of stamens or carpels. The genes regulating this growth suppression and how they have evolved remain largely unknown. We discovered that two classic developmental genes with ancient roles in controlling vegetative branching were recruited to suppress carpel development in maize. Our results highlight the power of forward genetics to reveal unpredictable genetic interactions and hidden pleiotropy of developmental genes. More broadly, our findings illustrate how ancient gene functions are recruited to new developmental contexts in the evolution of plant form.