bluuebunny/crossref_metadata_2025 huggingface dataset:
The impact of electrical stimulation protocols on neuronal cell survival and proliferation using cell-laden GelMA/graphene oxide hydrogels
Authors: Mendes Alexandre Xavier , do Nascimento Adriana Teixeira , Duchi Serena , Quigley Anita F. , Caballero Aguilar Lilith M. , Dekiwadia Chaitali , Kapsa Robert M. I. , Silva Saimon Moraes , Moulton Simon E.
Published: December 2022

Electrical stimulation of cell laden hydrogels promotes the survival and proliferation of neuronal cells when compared to cells seeded into flat surfaces.
Tb–Cu grain boundary diffusion effects on single- and multi-main-phase Nd–Fe–B based magnets
Authors: Yu Zhigao , Liu Xiangyi , He Jiayi , Cao Jiali , Fan Wenbing , Wu Yaxiang , Yu Hongya , Liu Zhongwu , Wang Zhan , Niu E.
Published: December 2022

Although Tb diffusion is deeper in multi-main-phase (MMP) magnets than in single-main-phase (SMP) magnets, the coercivity enhancement and squareness of diffused MMP magnets are lower than those of SMP magnets due to the larger gradient of anisotropy.
Li+ incorporation and defect-creation processes imposed by X-ray and UV irradiation in Li-codoped Y3Al5O12:Ce scintillation crystals
Authors: Laguta V. , Buryi M. , Babin V. , Machek P. , Zazubovich S. , Bartosiewicz K. , Kurosawa S. , Yamaji A. , Yoshikawa A. , Uličná K. , Chlan V. , Štěpánková H. , Nikl M.
Published: December 2022

This paper reports a detailed study of Li+ incorporation and electron and hole trapping in Li+-codoped Y3Al5O12:Ce garnet scintillation crystals, using the combination of the local probe EPR and NMR methods with optical characterization.
Structural and functional organization of germ plasm condensates
Authors: Chiappetta Austin , Liao Jeffrey , Tian Siran , Trcek Tatjana
Published: December 2022

Reproductive success of metazoans relies on germ cells. These cells develop early during embryogenesis, divide and undergo meiosis in the adult to make sperm and oocytes. Unlike somatic cells, germ cells are immortal and transfer their genetic material to new generations. They are also totipotent, as they differentiate into different somatic cell types. The maintenance of immortality and totipotency of germ cells depends on extensive post-transcriptional and post-translational regulation coupled with epigenetic remodeling, processes that begin with the onset of embryogenesis [1, 2]. At the heart of this regulation lie germ granules, membraneless ribonucleoprotein condensates that are specific to the germline cytoplasm called the germ plasm. They are a hallmark of all germ cells and contain several proteins and RNAs that are conserved across species. Interestingly, germ granules are often structured and tend to change through development. In this review, we describe how the structure of germ granules becomes established and discuss possible functional outcomes these structures have during development.
Konservative Behandlung eines Kreuzbandrisses beim Hund – Ein
Fallbericht
Authors: Häusler Kirsten
Published: December 2022

Ein Kreuzbandriss beim Hund sollte in der Regel operativ behandelt werden. Doch
für manche Hunde stellt eine Operation mit Vollnarkose ein zu hohes
Risiko dar. Im hier vorgestellten Fall des 9-jährigen Berner
Sennenhund-Rüden Diego kam eine Narkose nicht in Frage und der
Kreuzbandriss wurde mit beeindruckenden Ergebnissen konservativ behandelt. Die
Behandlung bestand aus einer Kombination von physikalischer und manueller
Therapie, Bewegungstherapie sowie dem Anpassen und Tragen einer speziell
angepassten Orthese. Die Verlaufskontrolle wurde u. a. mittels eines
instrumentieren Laufbands durchgeführt. Ob diese guten Ergebnisse
reproduzierbar sind, wird gegenwärtig in einer weiteren Studie
untersucht.
Physiotherapie für Hunde-Senioren – was,
wofür und wie viel?
Authors: Harms Oliver
Published: December 2022

Viele Veränderungen gehen mit dem Altern einher, z. B. eine Verminderung
der Lungenfunktion, eine Verminderung der Immunabwehr, eine Steigerung des
Fettanteils am Körpergewicht, aber auch der Verlust der
Mobilität aufgrund von abnehmender Gelenkbeweglichkeit, Muskelmasse und
Osteoarthrose. Wir zeigen Ihnen, wie Sie mit Physiotherapie Ihre alten Patienten
unterstützen, schmerzhafte Prozesse lindern und ihnen zu mehr
Lebensqualität verhelfen können und was es dabei zu beachten
gilt.
Predictive value of serum initial brain natriuretic peptide and troponin on functional prognosis in noncardiogenic patients with anterior and posterior circulation cerebral infarction
Authors: Lu Wan-Ting , Du Wen-Ting , Lu De-Sheng , You Jie , Li Hong-yan
Published: December 2022

Background Brain natriuretic peptide (BNP) and troponin have a close relationship with cardiogenic cerebral embolism (CCE), but their relationship with noncardiogenic patients with anterior circulation ischemia (ACI) and posterior circulation ischemia (PCI) is not clear.

Objective To explore the predictive value of serum initial BNP and troponin on the functional prognosis of patients with noncardiogenic ACI and PCI.

Methods Consecutive patients with first-episode cerebral infarction within 12 hours of symptom onset were enrolled in the present 1-year prospective cohort study. Serum levels of BNP and troponin were collected within 12 hours of onset. Infarction location was classified as ACI and PCI by magnetic resonance imaging (MRI). According to the modified Rankin Scale (mRS) score at 90 days after onset, ACI and PCI cases were respectively divided into a good prognosis group (mRS score between 0 and 2) and a poor prognosis group (mRS score between 3 and 6). The general state of health and results of laboratory examinations and other auxiliary examinations of all patients were recorded. Single-factor analysis and multivariate logistic regression analysis were used to assess the relationship between serum levels of BNP, troponin, and functional outcome.

Results The multivariate logistic regression found that higher levels of initial BNP (odds ratio [OR] = 1.024; 95% confidence interval [CI]: 1.006–1.041; p = 0.007) and C-reactive protein (CRP) (OR = 1.184; 95%CI: 1.024–1.369; p = 0.022) were independent predictors of poor functional prognosis of noncardiogenic PCI at 90 days after onset after adjusting for age, gender, ethnicity, history of hypertension and of diabetes.

Conclusions The levels of initial BNP and CRP were related to poor functional outcomes in noncardiogenic PCI patients at 3 months, independent of troponin.
Digital technology and its impacts on the sleep quality and academic performance during the pandemic
Authors: Cabral Luana Guimarães Lima , Queiroz Taynara Nunes , Pol-Fachin Laércio , Santos Adriana Rodrigues Libório dos
Published: December 2022

Background Sleep deficits caused by the overuse of digital technology is observed among medical students. Due to the coronavirus disease 2019 (COVID-19) pandemic, an emergency remote teaching method was put into practice, which may have resulted in changes in the sleep-wake cycle. The balance between the influences of external and internal synchronizers can be affected by sudden alterations in daily life, including changes in nightly habits and sleep quality, which can lead to increased levels of anxiety and reduced functional performance, for example.

Objective To understand the relationship between the use of digital technology, changes in the circadian cycle, and academic performance during the pandemic.

Methods The present is an analytical, cross-sectional, observational study in which a sample of 123 medical students filled out an online questionnaire on self-perception regarding sleep quality and academic performance before and during the pandemic.

Results Assessing changes in sleep quality and productivity, the study revealed that 100% of the students made continuous use of screens before bedtime. Thus, during the period of social distancing and remote classes, 77.2% of the students reported “poor” or “very poor academic performance, which was probably related to the fact that 65.9% of these students were unable to maintain their productivity due to daytime sleepiness.

Conclusions The prolonged use of screens was associated with poor sleep quality and changes in academic performance, with significant psychological impact. Thus, it is worth emphasizing the importance of sleep hygiene in light of the new forms of teaching implemented during the COVID-19 pandemic.
Reading fluency during the COVID-19 pandemic: a longitudinal and cross-sectional analysis
Authors: Alves Luciana Mendonça , Carvalho Isa Mourão , Santos Luiz Felipe dos , Ribeiro Gabriela de Lima , Freire Laura de Souza Cardoso , Martins-Reis Vanessa de Oliveira , Labanca Ludimila , Celeste Letícia Correa
Published: December 2022

Background International studies performed during the periods of social isolation highlighted the potential loss of student's learning skills. The present study fills a gap in Brazilian research on this topic and focuses on the development of reading fluency.

Objective To investigate the development of the reading fluency of students in the early years of elementary school during e-learning as a result of the social distancing measures put into effect due to the coronavirus disease 2019 (COVID-19) pandemic.

Methods Students from grades 2 to 5 were recorded. The number of words read per minute and of those read correctly per minute were analyzed. Descriptive statistical analysis was performed, using analysis of variance (ANOVA) for repeated measures with Bonferroni correction in the longitudinal study, and the t-test in the cross-sectional study.

Results In the cross-sectional study, 162 students participated. Only the comparison between the 2nd grade classes of 2020 and 2021 showed a statistically significant difference. In the prepandemic classes, the students had better results in reading accuracy than the students assessed during the pandemic. The longitudinal study included 75 students, who improved in fluency rate and accuracy as expected between March and December 2020. In March 2021, the results showed a drop, which may be related to school closures during the Brazilian summer vacation.

Conclusions The present research demonstrates the results of Brazilian students in terms of the development of reading fluency during the pandemic. There was an expressive development in grades 2 and 3, with stability in the following grades. The 2nd grade class of 2021 suffered a major impact due to the pandemic.
Clinical profile of tuberous sclerosis complex patients with and without epilepsy: a need for awareness for early diagnosis
Authors: Pereira Conceição Campanario da Silva , Dantas Felipe Diego Gomes , Manreza Maria Luiza Giraldes de
Published: December 2022

Background Tuberous sclerosis complex (TSC) is a multisystemic disorder. Its clinical features manifest differently in several organs, prompting the need for better knowledge.

Objective The goal of the present study is to evaluate the neurological findings of TSC, such as cerebral lesions and epilepsy, and to raise awareness of non-neurological findings that could contribute to an earlier diagnosis and treatment.

Methods This was a natural history study of patients with a definitive diagnosis of TSC who were referred to a specialized outpatient clinic and followed-up for 2 years with clinical and radiological exams.

Results A total of 130 TSC patients (59 males [45.4%], mean age 20.4 years old [1 to 56 years old]); 107 patients (82.3%) were diagnosed with epilepsy. Seizures predominantly began at < 1 year old (72.8%); focal seizures predominated (86.9%); epileptic spasms occurred in 34.5% of patients, and refractory epilepsy was present in 55.1%. Neuropsychiatric disorders, cortical tubers and cerebellar tubers were significantly more frequent in the epilepsy group. Moreover, rhabdomyomas were significantly more frequent in the epilepsy group (p = 0.044), while lymphangioleiomyomatosis was significantly less frequent in the epilepsy group (p = 0.009). Other non-neurological findings did not differ significantly between the groups with and without epilepsy.

Conclusions The present study of TSC patients demonstrated the predominantly neurological involvement and significantly higher proportion of TSC-associated neuropsychiatric disorders in the epilepsy group. Higher proportions of cortical and cerebellar tubers may be a risk factor for epilepsy and neurodevelopmental disorders.
Processing speed impairment in chronic inflammatory demyelinating polyneuropathy patients: a cross-sectional study
Authors: Senem Iara , Spedo Carina Telarolli , Conde Rodrigo Melo , Reis Geraldo Cassio dos , Santos Antônio Carlos dos , Barreira Amilton Antunes , Marques Jr Wilson ,   (in memoriam)
Published: December 2022

Background There is a lack of evidence of cognitive involvement in chronic inflammatory demyelinating polyneuropathy (CIDP) and, the reports about the involvement of the brain and central nervous system (CNS) are few and controversial. The Five Digit Test (FDT) evaluates processing speed (PS) and executive functions orally.

Objective To evaluate the performance on the FDT of CIDP patients with and without CNS (brain/cerebellum) alterations observed on brain Magnetic Resonance Imaging (MRI) scans.

Methods The Hospital Anxiety and Depression Scale (HADS, to assess neuropsychiatry symptoms), the Rasch-built Overall Disability Scale (R-ODS; to assess disability), and the FDT (to assess cognition) were applied to 14 CIDP patients and 24 age-matched healthy control subjects. The patients were submitted to routine brain MRI and, according to the results, they were divided into two groups: those with abnormalities on the MRI (CIDPabnl) and those with normal parameters on the MRI (CIDPnl). The FDT data of five CIDPnl patients and nine CIDPabnl subjects were analyzed. Comparisons between the groups were performed for each task of the FDT.

Results We found statistical differences for both groups of CIDP patients in terms of PS, for the patients spent more time performing the PS tasks than the controls. The PS measures were negatively associated with disability scores (reading: r = −0.47; p = 0.003; counting: r = −0.53; p = 0.001).

Conclusions Our data suggested the presence of PS impairment in CIDP patients. Disability was associated with slow PS.
Telehealth for Parkinson disease patients during the COVID-19 pandemic: the TeleParkinson study
Authors: Lima Danielle Pessoa , Gomes Vlademir Carneiro , Viana Júnior Antonio Brazil , Assis Francisco Mateus Carvalho de , Oliveira Pedro Henrique Avelino , Cunha Letícia Chaves Vieira , Braga Isabelly Cavalcante , Marques Miriam Lindsay Silva , Assunção Jézica de Sousa , Damasceno Adeline Louise Lopes , Barbosa Ana Lara Guerra , Moreira Arthur Holanda , Rocha Maria Eduarda Quidute Arrais , Porto Maria Eduarda Mendes Pontes , Chaves Érica Carneiro Barbosa , Oliveira Liliane Maria de , Roriz Filho Jarbas de Sá , Sobreira Neto Manoel Alves , Braga Neto Pedro
Published: December 2022

Background Telemedicine allows Parkinson disease (PD) patients to overcome physical barriers to access health care services and increases accessibility for people with mobility impairments.

Objective To investigate the feasibility indicators of a telehealth intervention for PD patients, including patient recruitment, attendance, technical issues, satisfaction, and benefits on levels of physical activity and sleep.

Methods We conducted a single-center, single-arm study of telehealth video consultations using WhatsApp (Meta Platforms, Inc., Menlo Park, CA, USA). Also, we collected the feasibility indicators as the primary endpoints. All the patients in the study were previously evaluated in person by the same team.

Results Patient recruitment, attendance, and technical issues rates were 61.3%, 90.5%, and 13.3%, respectively, with good scores of patient acceptance and satisfaction with the study intervention. The telehealth intervention improved physical activity, including the number of walks for at least 10 continuous minutes (p = 0.009) and the number of moderate-intensity activities lasting at least 10 continuous minutes (p = 0.001). The Pittsburgh sleep quality index (PSQI) scores also improved for one of its components: perceived sleep duration (p < 0.001) and for total Pittsburgh score (p < 0,001). The average travel time saving was 289.6 minutes, and money-saving was R$106.67 (around USD 18; almost 10% of the current minimum wage in Brazil).

Conclusions Direct-to-patient telehealth video consultations proved to be feasible and effective and had a positive impact on physical activity levels and sleep in PD patients.
Effects of magnetic geometry on dynamics of current-convective turbulence in tokamak divertor plasma
Authors: Stepanenko A. A.
Published: December 2022

The current-convective instability is one of the physical mechanisms that can drive fluctuating transport of plasma in the tokamak divertor. The impact of the tokamak magnetic geometry on spatial and temporal properties of saturated turbulence, driven by the instability, is investigated. The analysis is performed by employing the basic model of the instability [A. A. Stepanenko and S. I. Krasheninnikov, Phys. Plasmas 25, 012305 (2018)] extended to include contributions from the interchange drive. Turbulence simulations are carried out in BOUT++ under DIII-D-like conditions. The dependencies of amplitudes, spatial and frequency spectra of saturated plasma fluctuations on the curvature radius, and connection and shear lengths of magnetic field lines are found. It is demonstrated that taking the finite curvature of the magnetic field into account leads to a large increase in the turbulence amplitude, whereas the shear and connection lengths mainly affect the temporal dynamics of fluctuations and their spatial localization. In all cases shown, the turbulence frequency and wave-number spectra demonstrate better agreement with the experimentally observed ones, compared to the results of previous simulations based on the basic model of the current-convective instability.
Anomalous narrow-band optical anisotropy of MoO2 crystal in the visible regime
Authors: Yu Yu , Shen Wanfu , Ma Guoteng , Luo Qingqing , Huang Yufeng , Lu Huoqing , Wang Haile , Sun Lidong , Hu Chunguang
Published: December 2022

The emergence of anisotropic two-dimensional (2D) materials provides a platform for the cutting-edge nano- and optoelectronic devices. Exploring low-dimensional materials and revealing their anisotropic behavior are crucial for designing angle-dependent nanodevices. The metallicity of molybdenum dioxide (MoO2) crystal differentiates it from the most commonly studied semi-conductive anisotropic 2D materials. However, the studies on its optical anisotropy are still lacking. Here, two most commonly obtained shapes of rhombic and hexagonal MoO2 were synthesized by one step method of chemical vapor deposition. The rhombic and hexagonal MoO2 display a slight frequency shift of 1–5 cm−1 depending on the variation modes, but the Raman modes at 366 cm−1 remain unaltered. Using a combination of differential reflectance spectroscopy and reflectance difference spectroscopy, we revealed the unusual narrow-band optical anisotropies of rhombic and hexagonal MoO2 crystals in the visible wavelength region due to its unique metallic properties. Furthermore, it is found that the center wavelengths of the narrow-band optical anisotropy of the MoO2 crystal can be effectively adjusted by coherent optical interference. Our results present an interesting anisotropic metallic 2D candidate and an effective cavity-based approach to regulate the center wavelengths of as-obtained narrow-band optical anisotropy, which is highly beneficial for the wavelength-selected devices.
Pressure–strain interaction. I. On compression, deformation, and implications for Pi-D
Authors: Cassak Paul A. , Barbhuiya M. Hasan
Published: December 2022

The pressure–strain interaction describes the rate per unit volume that energy is converted between bulk flow and thermal energy in neutral fluids or plasmas. The term has been written as a sum of the pressure dilatation and the collisionless analog of viscous heating referred to as Pi−D, which isolates the power density due to compressible and incompressible effects, respectively. It has been shown that Pi−D can be negative, which makes its identification as collisionless viscous heating troubling. We argue that an alternate decomposition of pressure–strain interaction can be useful for interpreting the underlying physics. Since Pi−D contains both normal deformation and shear deformation, we propose grouping the normal deformation with the pressure dilatation to describe the power density due to converging/diverging flows, with the balance describing the power density purely due to shear deformation. We then develop a kinetic theory interpretation of compression, normal deformation, and shear deformation. We use the results to determine the physical mechanisms that can make Pi−D negative. We argue that both decompositions can be useful for the study of energy conversion in weakly collisional or collisionless fluids and plasmas, and implications are discussed.
Pressure–strain interaction. II. Decomposition in magnetic field-aligned coordinates
Authors: Cassak Paul A. , Barbhuiya M. Hasan , Weldon H. Arthur
Published: December 2022

In weakly collisional and collisionless magnetized plasmas, the pressure–strain interaction describes the rate of conversion between bulk flow and thermal energy density. In this study, we derive an analytical expression for the pressure–strain interaction in a coordinate system with an axis aligned with the local magnetic field. The result is eight groups of terms corresponding to different physical mechanisms that can contribute to the pressure–strain interaction. We provide a physical description of each term. The results are immediately of interest to weakly collisional and collisionless magnetized plasmas and the fundamental processes that happen therein, including magnetic reconnection, magnetized plasma turbulence, and collisionless shocks. The terms in the field-aligned coordinate decomposition are likely accessible to measurement with satellite observations.
Periodic motions in a class of discontinuous delayed systems with a parabolic boundary
Authors: Li Liping
Published: December 2022

Various periodic motions are investigated for a mass-spring-damper oscillator described by second-order discontinuous delayed systems with a parabolic boundary. The G-function related to a delayed variable is first developed to judge the crossing, sliding, and grazing motions at the boundary points. Then, basic and local mappings, together with their motion equations, are classified by current and delayed states of a local flow. It is shown that periodic motions can be predicted analytically in terms of the return mapping and the initial value function provided posteriorly. Finally, numerical simulations are given to illustrate the existence of slowly oscillating periodic solutions without or with sliding portions as well as a crossing periodic solution not slowly oscillating. These results not only enrich and extend switchability theory of discontinuous delayed systems, but also reveal some complicated periodic behaviors which cannot be found in continuous delayed systems and discontinuous systems without time delay.
Voltage modulated magnetic anisotropy of rare earth iron garnet thin films on a piezoelectric substrate
Authors: Gross Miela J. , Misba Walid A. , Hayashi Kensuke , Bhattacharya Dhritiman , Gopman Daniel B. , Atulasimha Jayasimha , Ross Caroline A.
Published: December 2022

Voltage-tuning of magnetic anisotropy is demonstrated in ferrimagnetic insulating rare earth iron garnets on a piezoelectric substrate, (011)-oriented PMN-PT. A 42 nm thick yttrium-substituted dysprosium iron garnet (YDyIG) film is grown via pulsed laser deposition followed by a rapid thermal anneal to crystallize the garnet into ≈5  μm diameter grains. The annealed polycrystalline film is magnetically isotropic in the film plane with total anisotropy dominated by shape and magnetoelastic contributions. Application of an electric field perpendicular to the substrate breaks the in-plane easy axis along [01[Formula: see text]] and an intermediate axis along [100]. The results are explained in terms of the piezoelectric remanent strain caused by poling the substrate, which is transferred to the YDyIG and modulates the magnetoelastic anisotropy.
In situ identification of surface sites in Cu–Pt bimetallic catalysts: Gas-induced metal segregation
Authors: Han Tongxin , Li Yuanyuan , Cao Yueqiang , Lee Ilkeun , Zhou Xinggui , Frenkel Anatoly I. , Zaera Francisco
Published: December 2022

The effect of gases on the surface composition of Cu–Pt bimetallic catalysts has been tested by in situ infrared (IR) and x-ray absorption spectroscopies. Diffusion of Pt atoms within the Cu–Pt nanoparticles was observed both in vacuum and under gaseous atmospheres. Vacuum IR spectra of CO adsorbed on CuPtx/SBA-15 catalysts (x = 0–∞) at 125 K showed no bonding on Pt regardless of Pt content, but reversible Pt segregation to the surface was seen with the high-Pt-content (x ≥ 0.2) samples upon heating to 225 K. In situ IR spectra in CO atmospheres also highlighted the reversible segregation of Pt to the surface and its diffusion back into the bulk when cycling the temperature from 295 to 495 K and back, most evidently for diluted single-atom alloy catalysts (x ≤ 0.01). Similar behavior was possibly observed under H2 using small amounts of CO as a probe molecule. In situ x-ray absorption near-edge structure data obtained for CuPt0.2/SBA-15 under both CO and He pointed to the metallic nature of the Pt atoms irrespective of gas or temperature, but analysis of the extended x-ray absorption fine structure identified a change in coordination environment around the Pt atoms, from a (Pt–Cu):(Pt–Pt) coordination number ratio of ∼6:6 at or below 445 K to 8:4 at 495 K. The main conclusion is that Cu–Pt bimetallic catalysts are dynamic, with the composition of their surfaces being dependent on temperature in gaseous environments.
Heavily Ge-doped GaN as transparent current spreading layer for blue tunnel junction light emitting diodes
Authors: Berger C. , Neugebauer S. , Hörich F. , Dadgar A. , Strittmatter A.
Published: December 2022

We report on metalorganic vapor phase epitaxy of highly conductive germanium-doped GaN layers and their application for blue tunnel-junction light emitting diodes (TJ-LEDs). Using Ge as donor, carrier densities of up to 2 × 1020 cm−3 and low bulk resistivities down to 3 × 10−4 Ωcm are achieved. Under optimum growth conditions, no degradation of the crystalline quality is observed and layers exhibit high transparency making GaN:Ge very attractive as current spreading layer in light emitting devices. We have realized GaN-based TJ-LEDs by capping conventional InGaN LED structures with highly doped GaN:Ge. Such TJ-LEDs withstand operation currents up to 20 kA/cm2 in continuous and up to 60 kA/cm2 in pulsed operation conditions. Moreover, TJ-LEDs exhibit homogeneous electroluminescence and light output through the top surface that is increased by more than 60% as compared to conventional LEDs with transparent indium tin oxide contacts. The impact of the doping profile, carrier gas conditions, and acceptor activation by annealing for low-resistive TJ characteristics is discussed. Light output and current voltage characteristics of blue-light emitting devices with GaN-TJ are presented at low and high-current densities.
High-sensitivity fluorescence-detected multidimensional electronic spectroscopy through continuous pump–probe delay scan
Authors: Sahu Amitav , Bhat Vivek N. , Patra Sanjoy , Tiwari Vivek
Published: December 2022

Fluorescence-detected multidimensional electronic spectroscopy (fMES) promises high sensitivity compared to conventional approaches and is an emerging spectroscopic approach toward combining the advantages of MES with the spatial resolution of a microscope. Here, we present a visible white light continuum-based fMES spectrometer and systematically explore the sensitivity enhancement expected from fluorescence detection. As a demonstration of sensitivity, we report room temperature two-dimensional coherence maps of vibrational quantum coherences in a laser dye at optical densities of ∼2–3 orders of magnitude lower than conventional approaches. This high sensitivity is enabled by a combination of biased sampling along the optical coherence time axes and a rapid scan of the pump–probe waiting time T at each sample. A combination of this approach with acousto-optic phase modulation and phase-sensitive lock-in detection enables measurements of room temperature vibrational wavepackets even at the lowest ODs. Alternative faster data collection schemes, which are enabled by the flexibility of choosing a non-uniform undersampled grid in the continuous T scanning approach, are also demonstrated.
Coherent THz wave emission from HgTe quantum dots
Authors: Apretna T. , Nilforoushan N. , Tignon J. , Dhillon S. , Carosella F. , Ferreira R. , Lhuillier E. , Mangeney J.
Published: December 2022

Mercury telluride (HgTe) nanocrystals (NCs) are very promising for THz technology as they exhibit broad THz absorption resonances and a carrier lifetime of a few picoseconds as well as being easily fabricated using solution synthesis. In this work, we show their light emission properties in the THz spectral range, up until now unexplored, and show how THz pulse generation can be used for microscopic insights into these NCs. In particular, we report on coherent THz emission from large HgTe NCs excited by linearly polarized optical pulses via second-order nonlinear effects. The peak emission frequency is tunable from 0.4 to 0.8 THz by varying incident angles of optical pulses from 0° to 45°. Our results reveal that the THz emission is induced by transient photocurrents arising from both photogalvanic and photon drag effects. By pushing the light emission of colloidal quantum dots down to the THz spectral range, our study expands the application fields of NCs, especially toward the development of easily integrable and tunable THz emitters and quantum THz devices.
High-speed non-contact measurement of elasto-optic coefficient via laser-induced phonons
Authors: Li Jiarui , Zhang Hongyuan , Chen Xinyi , Le Taoran , Wei Haoyun , Li Yan
Published: December 2022

The elasto-optic coefficient, which describes the interaction of acoustic waves and light in a medium, allows a contrast mechanism in optomechanics. However, the non-contact measurement is a challenge, limiting the study of some materials such as liquids. We present a high-speed non-contact method based on laser-induced phonons. The elasto-optic coefficients of common liquids are measured with only 10 ms and an averaged relative standard deviation of 1.52%, complementing the rare liquid data. By deciphering Brillouin spectra, the elasto-optic coefficient and viscoelastic parameters can be obtained simultaneously, and the introduction of the elasto-optic coefficient makes the characterization more sensitive. Benefiting from spatially resolved measurement, the elasto-optic coefficient is mapped to provide another contrast mechanism for mechanical imaging and may prove useful to characterize biological cells and tissues.
Biochar and fertiliser interactions in crop and pasture production
Authors: Solaiman Zakaria
Published: December 2022

This foreword provides a summary of papers included in this special issue on biochar and fertiliser interactions for crop and pastures productivity. This special issue includes published papers on how biochar and fertiliser affect soil health and crop yields and overcome soil constraints such as acidity, salinity, low fertility and remediation of metal and pesticides contaminated soils.
Heterogeneous stochastic bifurcations explain intrinsic oscillatory patterns in entorhinal cortical stellate cells
Authors: Mittal Divyansh , Narayanan Rishikesh
Published: December 2022

Stellate cells (SC) in the medial entorhinal cortex manifest intrinsic membrane potential oscillatory patterns. Although different theoretical frameworks have been proposed to explain these patterns, a robust unifying framework that jointly accounts for intrinsic heterogeneities and stochasticity is missing. Here, we first performed in vitro patch-clamp electrophysiological recordings from rat SCs and found pronounced cell-to-cell variability in their characteristic physiological properties, including peri-threshold oscillatory patterns. We demonstrate that noise introduced into two independent populations (endowed with deterministic or stochastic ion-channel gating kinetics) of heterogeneous biophysical models yielded activity patterns that were qualitatively similar to electrophysiological peri-threshold oscillatory activity in SCs. We developed spectrogram-based quantitative metrics for the identification of valid oscillations and confirmed that these metrics reliably captured the variable-amplitude and arhythmic oscillatory patterns observed in electrophysiological recordings. Using these quantitative metrics, we validated activity patterns from both heterogeneous populations of SC models, with each model assessed with multiple trials of different levels of noise at distinct membrane depolarizations. Our analyses unveiled the manifestation of stochastic resonance (detection of the highest number of valid oscillatory traces at an optimal level of noise) in both heterogeneous populations of SC models. Finally, we show that a generalized network motif comprised of a slow negative feedback loop amplified by a fast positive feedback loop manifested stochastic bifurcations and stochastic resonance in the emergence of oscillations. Together, through a unique convergence of the degeneracy and stochastic resonance frameworks, our unifying framework centered on heterogeneous stochastic bifurcations argues for state-dependent emergence of SC oscillations.
Abrupt loss and uncertain recovery from fires of Amazon forests under low climate mitigation scenarios
Authors: Cano Isabel Martínez , Shevliakova Elena , Malyshev Sergey , John Jasmin G. , Yu Yan , Smith Benjamin , Pacala Stephen W.
Published: December 2022

Tropical forests contribute a major sink for anthropogenic carbon emissions essential to slowing down the buildup of atmospheric CO
2
and buffering climate change impacts. However, the response of tropical forests to more frequent weather extremes and long-recovery disturbances like fires remains uncertain. Analyses of field data and ecological theory raise concerns about the possibility of the Amazon crossing a tipping point leading to catastrophic tropical forest loss. In contrast, climate models consistently project an enhanced tropical sink. Here, we show a heterogeneous response of Amazonian carbon stocks in GFDL-ESM4.1, an Earth System Model (ESM) featuring dynamic disturbances and height-structured tree–grass competition. Enhanced productivity due to CO
2
fertilization promotes increases in forest biomass that, under low emission scenarios, last until the end of the century. Under high emissions, positive trends reverse after 2060, when simulated fires prompt forest loss that results in a 40% decline in tropical forest biomass by 2100. Projected fires occur under dry conditions associated with El Niño Southern Oscillation and the Atlantic Multidecadal Oscillation, a response observed under current climate conditions, but exacerbated by an overall decline in precipitation. Following the initial disturbance, grassland dominance promotes recurrent fires and tree competitive exclusion, which prevents forest recovery. EC-Earth3-Veg, an ESM with a dynamic vegetation model of similar complexity, projected comparable wildfire forest loss under high emissions but faster postfire recovery rates. Our results reveal the importance of complex nonlinear responses to assessing climate change impacts and the urgent need to research postfire recovery and its representation in ESMs.
Human disturbance compresses the spatiotemporal niche
Authors: Gilbert Neil A. , Stenglein Jennifer L. , Pauli Jonathan N. , Zuckerberg Benjamin
Published: December 2022

Human disturbance may fundamentally alter the way that species interact, a prospect that remains poorly understood. We investigated whether anthropogenic landscape modification increases or decreases co-occurrence—a prerequisite for species interactions—within wildlife communities. Using 4 y of data from >2,000 camera traps across a human disturbance gradient in Wisconsin, USA, we considered 74 species pairs (classifying pairs as low, medium, or high antagonism to account for different interaction types) and used the time between successive detections of pairs as a measure of their co-occurrence probability and to define co-occurrence networks. Pairs averaged 6.1 [95% CI: 5.3, 6.8] d between detections in low-disturbance landscapes (e.g., national forests) but 4.1 [3.5, 4.7] d between detections in high-disturbance landscapes, such as those dominated by urbanization or intensive agriculture. Co-occurrence networks showed higher connectance (i.e., a larger proportion of the possible co-occurrences) and greater proportions of low-antagonism pairs in disturbed landscapes. Human-mediated increases in species abundance (possibly via resource subsidies) appeared more important than behavioral mechanisms (e.g., changes in daily activity timing) in driving these patterns of compressed co-occurrence in disturbed landscapes. The spatiotemporal compression of species co-occurrences in disturbed landscapes likely strengthens interactions like competition, predation, and infection unless species can avoid each other at fine spatiotemporal scales. Regardless, human-mediated increases in co-occurrence with—and hence increased exposure to—predators or competitors might elevate stress levels in individual animals, with possible cascading effects across populations, communities, and ecosystems.
Glacial meltwater determines the balance between autotrophic and heterotrophic processes in a Greenland fjord
Authors: Sejr Mikael K. , Bruhn Annette , Dalsgaard Tage , Juul-Pedersen Thomas , Stedmon Colin A. , Blicher Martin , Meire Lorenz , Mankoff Kenneth D. , Thyrring Jakob
Published: December 2022

Global warming accelerates melting of glaciers and increases the supply of meltwater and associated inorganic particles, nutrients, and organic matter to adjacent coastal seas, but the ecosystem impact is poorly resolved and quantified. When meltwater is delivered by glacial rivers, the potential impact could be a reduction in light and nutrient availability for primary producers while supplying allochthonous carbon for heterotrophic processes, thereby tipping the net community metabolism toward heterotrophy. To test this hypothesis, we determined physical and biogeochemical parameters along a 110-km fjord transect in NE Greenland fjord, impacted by glacial meltwater from the Greenland Ice Sheet. The meltwater is delivered from glacier-fed river outlets in the inner parts of the fjord, creating a gradient in salinity and turbidity. The planktonic primary production was low, 20–45 mg C m−2d−1, in the more turbid inner half of the fjord, increasing 10-fold to around 350 mg C m−2d−1in the shelf waters outside the fjord. Plankton community metabolism was measured at three stations, which displayed a transition from net heterotrophy in the inner fjord to net autotrophy in the coastal shelf waters. Respiration was significantly correlated to turbidity, with a 10-fold increase in the inner turbid part of the fjord. We estimated the changes in meltwater input and sea ice coverage in the area for the last 60 y. The long-term trend and the observed effects demonstrated the importance of freshwater runoff as a key driver of coastal ecosystem change in the Arctic with potential negative consequences for coastal productivity.
Creative destruction: New protein folds from old
Authors: Alvarez-Carreño Claudia , Gupta Rohan J. , Petrov Anton S. , Williams Loren Dean
Published: December 2022

Mechanisms of emergence and divergence of protein folds pose central questions in biological sciences. Incremental mutation and stepwise adaptation explain relationships between topologically similar protein folds. However, the universe of folds is diverse and riotous, suggesting more potent and creative forces are at play. Sequence and structure similarity are observed between distinct folds, indicating that proteins with distinct folds may share common ancestry. We found evidence of common ancestry between three distinct β-barrel folds: Scr kinase family homology (SH3), oligonucleotide/oligosaccharide-binding (OB), and cradle loop barrel (CLB). The data suggest a mechanism of fold evolution that interconverts SH3, OB, and CLB. This mechanism, which we call creative destruction, can be generalized to explain many examples of fold evolution including circular permutation. In creative destruction, an open reading frame duplicates or otherwise merges with another to produce a fused polypeptide. A merger forces two ancestral domains into a new sequence and spatial context. The fused polypeptide can explore folding landscapes that are inaccessible to either of the independent ancestral domains. However, the folding landscapes of the fused polypeptide are not fully independent of those of the ancestral domains. Creative destruction is thus partially conservative; a daughter fold inherits some motifs from ancestral folds. After merger and refolding, adaptive processes such as mutation and loss of extraneous segments optimize the new daughter fold. This model has application in disease states characterized by genetic instability. Fused proteins observed in cancer cells are likely to experience remodeled folding landscapes and realize altered folds, conferring new or altered functions.
Muscle injury causes long-term changes in stem-cell DNA methylation
Authors: Falick Michaeli Tal , Sabag Ofra , Fok Rimma , Azria Batia , Monin Jonathan , Nevo Yuval , Gielchinsky Yuval , Berman Benjamin P. , Cedar Howard , Bergman Yehudit
Published: December 2022

Injury to muscle brings about the activation of stem cells, which then generate new myocytes to replace damaged tissue. We demonstrate that this activation is accompanied by a dramatic change in the stem-cell methylation pattern that prepares them epigenetically for terminal myocyte differentiation. These de- and de novo methylation events occur at regulatory elements associated with genes involved in myogenesis and are necessary for activation and regeneration. Local injury of one muscle elicits an almost identical epigenetic change in satellite cells from other muscles in the body, in a process mediated by circulating factors. Furthermore, this same methylation state is also generated in muscle stem cells (MuSCs) of female animals following pregnancy, even in the absence of any injury. Unlike the activation-induced expression changes, which are transient, the induced methylation profile is stably maintained in resident MuSCs and thus represents a molecular memory of previous physiological events that is probably programmed to provide a mechanism for long-term adaptation.
Hierarchical unimodal processing within the primary somatosensory cortex during a bimodal detection task
Authors: Parra Sergio , Díaz Héctor , Zainos Antonio , Alvarez Manuel , Zizumbo Jerónimo , Rivera-Yoshida Natsuko , Pujalte Sebastián , Bayones Lucas , Romo Ranulfo , Rossi-Pool Román
Published: December 2022

Do sensory cortices process more than one sensory modality? To answer these questions, scientists have generated a wide variety of studies at distinct space-time scales in different animal models, and often shown contradictory conclusions. Some conclude that this process occurs in early sensory cortices, but others that this occurs in areas central to sensory cortices. Here, we sought to determine whether sensory neurons process and encode physical stimulus properties of different modalities (tactile and acoustic). For this, we designed a bimodal detection task where the senses of touch and hearing compete from trial to trial. Two Rhesus monkeys performed this novel task, while neural activity was recorded in areas 3b and 1 of the primary somatosensory cortex (S1). We analyzed neurons’ coding properties and variability, organizing them by their receptive field’s position relative to the stimulation zone. Our results indicate that neurons of areas 3b and 1 are unimodal, encoding only the tactile modality in both the firing rate and variability. Moreover, we found that neurons in area 3b carried more information about the periodic stimulus structure than those in area 1, possessed lower response and coding latencies, and had a lower intrinsic time scale. In sum, these differences reveal a hidden processing-based hierarchy. Finally, using a powerful nonlinear dimensionality reduction algorithm, we show that the activity from areas 3b and 1 can be separated, establishing a clear division in the functionality of these two subareas of S1.
Teacher talk in English-medium instruction classes in Japanese universities
Authors: Davila Gilder
Published: December 2022

English-medium instruction (EMI) courses in higher education have increased dramatically over the past decade and Japan is no exception. In the implementation of EMI courses, the role of English and the local language (Japanese) during content education is a subject of debate. The present study analyses EMI teacher talk by looking at aspects such as speech structure, and the role of language during content-education. Twelve undergraduate classes from four academic subjects in Economics, Ethics in Science, Project Planning, and Development Studies (three classes from each subject) were observed and recorded. Transcripts from these classes were analysed using Christie’s (1989) classroom discourse approach of curriculum genre, and Bernstein’s (1996) notion of horizontal and vertical discourses. Research findings revealed that there are similarities in EMI teachers’ classroom speech structure. However, the learning context has an effect on the role of English language which in turn influences content education.
Manoeuvres of dissent in landscapes of annexation
Authors: Volvach Natalia
Published: December 2022

Building on semiotic landscapes research, the present paper seeks to expand the existing field with its
exploration of protest through the lens of turbulence (Stroud, 2015a). While making
visible the fabric of resistance in semiotic landscapes of annexed Crimea, the ethnographic engagement with the interactional and
visual data provides insights into small-scale performative acts of protest. It shows that protest evolves as a manoeuvring act
across a minefield of possibilities and constraints and manifests itself materially and discursively. More specifically, acts of
protest emerge out of an agential intra-action of humans and non-humans, thus revealing the necessity of synergies between people
and objects. Such intra-actions create interpretative ambiguity. Protestors deliberately play on this ambiguity to simultaneously
conceal and to visibilise dissent. Jointly achieved performative acts of protest, if only temporary, create turbulence and
unsettle the status of Crimea as a ‘Russian’ space, thus disturbing the status quo in the area.
From grammaticalization to Diachronic Construction Grammar
Authors: Gildea Spike , Barðdal Jóhanna
Published: December 2022

The term grammaticalization originally denoted a particular outcome of language change (lexis > morphology), then got expanded to practically all studies involving language change, the processes that create such changes, and a theory modeling these. These expansions have been challenged in the literature as conceptually flawed. A usage-based analysis of the evolution of the concept culminates in the use of the term grammaticalization as a “flag” of a particular approach to linguistics. However, the theoretical premises of grammaticalization studies are entirely compatible with the premises of Diachronic Construction Grammar (DCxG). All studies within the “expanded” concept of grammaticalization can be explicitly modeled within DCxG, which provides formalism of sufficient detail to map the gradual nature of language change in cases of grammaticalization and beyond. Consequently, the most vigorous attacks on grammaticalization lose power when grammaticalization is seen as part of a larger, more complete theory of language and language change.