bluuebunny/crossref_metadata_2025 huggingface dataset:
P.212 Demographic Trends in Canadian Neurosurgery Training & Academic
Neurosurgery
Authors: Malvea A , Yan C , Nguyen L , Beaudry-Richard A , Wai E , Tsai EC
Published: January 2022

Background: Exploring current trends in career
outcomes can guide further expansion and diversity in neurosurgery
demographics, as well as inform medical trainees of qualifications required
for a career in neurosurgery. This study therefore aims to explore temporal
trends and gender distribution in training, teaching, and leadership
positions among currently practicing neurosurgeons.
Methods: A list of practicing Canadian
neurosurgeons and their certification year, degrees, fellowships, and
teaching positions was created using publicly available information and
phone/email confirmation by surgeons. Results: We
identified 297 neurosurgeons currently practicing in Canada (F=32, M=265).
There was a significant trend towards a greater number of neurosurgical
staff having at least one advanced degree or fellowship over time (p=0.0012,
p=0.0048 respectively), with no significant difference between proportions
of males and females. Within academia, women represent 33% of adjunct
professors, 8% of associate professors, and 15.2% of full professors. Two
neurosurgical departments in Canada are led by women.
Conclusions: Literature shows there is an
underrepresentation of women in neurosurgery, particularly in higher-ranking
teaching and leadership positions, yet our results suggest there is no
significant differences in qualifications between males and females. Further
exploration is needed to identify reasons underlying these trends and
propose solutions to promote growth in the field.
The emergence of ‘Transeurasian’ language families in Northeast Asia as viewed from archaeological evidence
Authors: Miyamoto Kazuo
Published: January 2022

From a linguistic standpoint, Proto-Japonic and Proto-Koreanic are assumed to have split off the Transeurasian languages in southern Manchuria. The linguistic idea that Proto-Japonic came earlier than Proto-Koreanic in the chronological scheme means that the Proto-Japonic language first entered the Korean Peninsula, and from there spread to the Japanese archipelago at the beginning of the Yayoi period, around the ninth century BC, while the arrival of Proto-Koreanic in southern Korea is associated with the spread of the rolled rim vessel culture around the fifth century BC. The genealogical sequence of the Pianpu, Mumun and Yayoi cultures, which shared the same pottery production techniques, indicates the spread of Proto-Japonic. On the other hand, migrants moved from Liaodong to the Korean Peninsula and established the rolled rim vessel culture. This population movement was probably due to social and political reasons as the Yan state enlarged its territory eastward. The Proto-Koreanic of the rolled rim vessel culture later spread to the Korean Peninsula and gradually drove out Proto-Japonic, becoming the predecessor of the Koreanic. In this paper, I examine the spread of Proto-Japonic and Proto-Koreanic in Northeast Asia based on archaeological evidence, focusing especially on the genealogy of pottery styles and pottery production techniques.
Occupational exposure to severe acute respiratory coronavirus virus 2 (SARS-CoV-2) and risk of infection among healthcare personnel
Authors: Shah Vishal P. , Breeher Laura E. , Alleckson Julie M. , Rivers David G. , Wang Zhen , Stratton Emily R. , Farah Wigdan , Hainy Caitlin M. , Swift Melanie D.
Published: January 2022

Objective:

To assess the rate and factors associated with healthcare personnel (HCP) testing positive for severe acute respiratory coronavirus virus 2 (SARS-CoV-2) after an occupational exposure.

Design:

Retrospective cohort study.

Setting:

Academic medical center with sites in Minnesota, Wisconsin, Arizona, and Florida.

Participants:

HCP with a high or medium risk occupational exposure to a patient or other HCP with SARS-CoV-2.

Methods:

We reviewed the records of HCP with significant occupational exposures from March 20, 2020, through December 31, 2020. We then performed regression analysis to assess the impact of demographic and occupational variables to assess their impact on the likelihood of testing positive for SARS-CoV-2.

Results:

In total, 2,253 confirmed occupational exposures occurred during the study period. Employees were the source for 57.1% of exposures. Overall, 101 HCP (4.5%) tested positive in the postexposure period. Of these, 80 had employee sources of exposure and 21 had patient sources of exposure. The postexposure infection rate was 6.2% when employees were the source, compared to 2.2% with patient sources. In a multivariate analysis, occupational exposure from an employee source had a higher risk of testing positive compared to a patient source (odds ratio [OR], 3.22; 95% confidence interval [CI], 1.72–6.04). Sex, age, high-risk exposure, and HCP role were not associated with an increased risk of testing positive.

Conclusions:

The risk of acquiring coronavirus disease 2019 (COVID-19) following a significant occupational exposure has remained relatively low, even in the prevaccination era. Exposure to an infectious coworker carries a higher risk than exposure to a patient. Continued vigilance and precautions remain necessary in healthcare settings.
On the frequency selection mechanism of the low-Re flow around rectangular cylinders
Authors: Chiarini A. , Quadrio M. , Auteri F.
Published: January 2022

In the flow past elongated rectangular cylinders at moderate Reynolds numbers, vortices shedding from the leading- and trailing-edge corners are frequency locked by the impinging leading-edge vortex instability. The present work investigates how the chord-based Strouhal number varies with the aspect ratio of the cylinder at a Reynolds number (based on the cylinder thickness and the free-stream velocity) of

$Re=400$

, i.e. when locking is strong. Several two-dimensional, nonlinear simulations are run for rectangular and D-shaped cylinders, with the aspect ratio ranging from

$1$

to

$11$

, and a global linear stability analysis of the flow is performed. The shedding frequency observed in the nonlinear simulations is predicted fairly well by the eigenfrequency of the leading eigenmode. The inspection of the structural sensitivity confirms the central role of the trailing-edge vortex shedding in the frequency locking, as already assumed by other authors. Surprisingly, however, the stepwise increase of the Strouhal number with the aspect ratio reported by several previous works is not fully reproduced. Indeed, with increasing aspect ratio, two distinct flow behaviours are observed, associated with two flow configurations where the interaction between the leading- and trailing-edge vortices is different. These two configurations are fully characterised, and the mechanism of selection of the flow configuration is discussed. Lastly, for aspect ratios close to the jump between two consecutive shedding modes, the Strouhal number is found to present hysteresis, implying the existence of multiple stable configurations. Continuing the lower shedding-mode branch by increasing the aspect ratio, we found that the periodic configuration loses stability via a Neimark–Sacker bifurcation leading to different Arnold tongues. This hysteresis can explain, at least partially, the significant scatter of existing experimental and numerical data.
Non-adiabatic modulation of premixed-flame thermoacoustic frequencies in slender tubes
Authors: Flores-Montoya Enrique , Muntean Victor , Sánchez-Sanz Mario , Martínez-Ruiz Daniel
Published: January 2022

This paper presents an experimental study of the influence of heat losses on the onset of thermoacoustic instabilities in methane–air premixed flames propagating in a horizontal tube of diameter,$D = 10$mm. Flames are ignited at the open end of the tube and propagate towards the closed end undergoing strong oscillations of different features owing to the interaction with acoustic waves. The frequency of oscillation and its axial location are controlled through the tube length$L$and the intensity of heat losses. These parameters are respectively modified in the experiments by a moveable piston and a circulating thermal bath of water prescribing temperature conditions. Main experimental observations show that classical one-dimensional predictions of the oscillation frequency do not accurately describe the phenomena under non-adiabatic real scenarios. In addition to the experimental measurements, a quasi-one-dimensional analysis of the burnt gases is provided, which introduces the effect of heat losses at the wall of the tube on the interplay between the acoustic field and the reaction sheet. As a result, this analysis provides an improved description of the interaction and accurately predicts the excited flame-oscillation harmonics through the eigenvalues of the non-adiabatic acoustics model. Unlike the original one-dimensional analysis, the comparison between the flame oscillation frequency provided by the non-adiabatic extended theory and the frequencies measured in our experiments is in excellent agreement in the whole range of temperatures considered. This confirms the importance of heat losses in the modulation of the instabilities and the transition between different flame oscillation regimes.
Linear stability of a rotating liquid column revisited
Authors: Dubey Pulkit , Roy Anubhab , Subramanian Ganesh
Published: January 2022

We revisit the somewhat classical problem of the linear stability of a rigidly rotating liquid column in this article. Although the literature pertaining to this problem dates back to 1959, the relation between inviscid and viscous stability criteria has not yet been clarified. While the viscous criterion for stability, given by$We < n^2 + k^2 -1$, is both necessary and sufficient, this relation has only been shown to be sufficient in the inviscid case. Here,$We = \rho \varOmega ^2 a^3 / \gamma$is the Weber number and measures the relative magnitudes of the centrifugal and surface tension forces, with$\varOmega$being the angular velocity of the rigidly rotating column,$a$the column radius,$\rho$the density of the fluid and$\gamma$the surface tension coefficient;$k$and$n$denote the axial and azimuthal wavenumbers of the imposed perturbation. We show that the subtle difference between the inviscid and viscous criteria arises from the surprisingly complicated picture of inviscid stability in the$We$–$k$plane. For all$n > 1$, the viscously unstable region, corresponding to$We > n^2 + k^2-1$, contains an infinite hierarchy of inviscidly stable islands ending in cusps, with a dominant leading island. Only the dominant island, now infinite in extent along the$We$axis, persists for$n=1$. This picture may be understood, based on the underlying eigenspectrum, as arising from the cascade of coalescences between a retrograde mode, that is the continuation of the cograde surface-tension-driven mode across the zero Doppler frequency point, and successive retrograde Coriolis modes constituting an infinite hierarchy.
Acoustic streaming in Maxwell fluids generated by standing waves in two-dimensional microchannels
Authors: Vargas C. , Campos-Silva I. , Méndez F. , Arcos J. , Bautista O.
Published: January 2022

In this work, a semianalytic solution for the acoustic streaming phenomenon, generated by standing waves in Maxwell fluids through a two-dimensional microchannel (resonator), is derived. The mathematical model is non-dimensionalized and several dimensionless parameters that characterize the phenomenon arise: the ratio between the oscillation amplitude of the resonator and the half-wavelength (

$\eta =2A/\lambda _{a}$

); the product of the fluid relaxation time times the angular frequency known as the Deborah number (

$De=\lambda _{1}\omega$

); the aspect ratio between the microchannel height and the wavelength (

$\epsilon =2 H_{0}/\lambda _{a}$

); and the ratio between half the height of the microchannel and the thickness of the viscous boundary layer (

$\alpha =H_{0}/\delta _{\nu }$

). In the limit when

$\eta \ll 1$

, we obtain the hydrodynamic behaviour of the system using a regular perturbation method. In the present work, we show that the acoustic streaming speed is proportional to

$\alpha ^{2.65}De^{1.9}$

, and the acoustic pressure varies as

$\alpha ^{6/5}De^{1/2}$

. Also, we have found that the growth of inner vortex is due to convective terms in the Maxwell rheological equation. Furthermore, the velocity antinodes show a high dependency on the Deborah number, highlighting the fluid's viscoelastic properties and the appearance of resonance points. Due to the limitations of perturbation methods, we will only analyse narrow microchannels.
Hyphenated Identities: Voices from the Watchtower During the Cypriot Civil War
Authors: Lamnisos Tasos
Published: January 2022

As an implication of the ethnically and nationally diverse nature of Mediterranean polities, identification-driven boundary-making strategies bear considerable relevance for their political processes, both in the contemporary context and in the historical past. By utilizing a Discourse-Historical Approach (DHA), this study provides an interpretative exploration of Greek-Cypriot elite discursive framing strategies regarding Turkish-Cypriot and Greek-Cypriot ethno-national identity during the Cypriot Civil War (1963–1967). The available historical interpretations of this period lead us to expect an exclusionary strategy of boundary contraction to be more prevalent than the inclusionary one of boundary expansion in the discourse of Greek-Cypriot elites. Through an examination of a sample of primary textual sources, the analysis disconfirms such an expectation, as elite figures primarily constructed broader, inclusive frames of ethno-national identity during the civil war. The relative absence of boundary contraction and the prevalence of boundary expansion indicate the applicability of Wimmer’s (2008) universalist approach to ethnic boundary-making, in contrast to the expectations that are built by the Cyprus-specific historical evidence. This study thus lays the groundwork for future research to delineate the discursive framing strategies of elite figures in Cyprus and beyond the ethno-nationally divided island.
Principal bundles on two-dimensional CW-complexes with disconnected structure group
Authors: Oliveira André G.
Published: January 2022

Given any topological group G, the topological classification of principal G-bundles over a finite CW-complex X is long known to be given by the set of free homotopy classes of maps from X to the corresponding classifying space BG. This classical result has been long-used to provide such classification in terms of explicit characteristic classes. However, even when X has dimension 2, there is a case in which such explicit classification has not been explicitly considered. This is the case where G is a Lie group, whose group of components acts nontrivially on its fundamental group
$\pi_1G$
. Here, we deal with this case and obtain the classification, in terms of characteristic classes, of principal G-bundles over a finite CW-complex of dimension 2, with G is a Lie group such that
$\pi_0G$
is abelian.
Hausdorff dimension of the set of almost convergent sequences
Authors: Usachev Alexandr
Published: January 2022

The paper deals with the sets of numbers from [0,1] such that their binary representation is almost convergent. The aim of the study is to compute the Hausdorff dimensions of such sets. Previously, the results of this type were proved for a single summation method (e.g. Cesàro, Abel, Toeplitz). This study extends the results to a wide range of matrix summation methods.
An obstacle-avoiding and stiffness-tunable modular bionic soft robot
Authors: Liu Zhaoyu , Wang Yuxuan , Wang Jiangbei , Fei Yanqiong , Du Qitong
Published: January 2022

The aim of this work is to design and model a novel modular bionic soft robot for crawling and crossing obstacles. The modular bionic soft robot is composed of several serial driving soft modules, each module is composed of two parallel soft actuators. By analyzing the influence of working pressure and manufacturing size on the stiffness of the modular bionic soft robot, the nonlinear variable stiffness model of the modular bionic soft robot is established. Based on this model, the spatial states and design parameters of the modular bionic soft robot are discussed when the modular bionic soft robot can pass through the obstacle. Experiments show that when the inflation air pressure of the modular bionic soft robot is 70 kPa, its speed can reach 7.89 mm/s and the height of obstacles passed by it can reach 42.8 mm. The feasibility of the proposed modular bionic soft robot and nonlinear variable stiffness model is verified by locomotion experiments.
Does a prenatal diagnosis affect mortality and morbidity for neonatal arterial switch operation
Authors: Guvenc Osman , Beken Serdar , Inamlik Aysegul , Albayrak Eda , Temur Bahar , Basgoze Serdar , Aydin Selim , Saygi Murat , Ödemiş Ender , Erek Ersin , Toygar Ayse Korkmaz
Published: January 2022

Background:

The effect of prenatal diagnosis on prognosis in patients with transposition of the great arteries is not clear. In this study, we compared the outcomes after arterial switch operation.

Methods:

Outcome of 112 patients who had arterial switch operation in the neonatal period were analysed. The patients were divided into two groups: those who had prenatal diagnosis (Group 1; n = 34) and those who did not (Group 2; n = 78). The patients were also classified based on their diagnosis: simple transposition, transposition with ventricular septal defect and/or aortic arch hypoplasia, and Taussig–Bing anomaly.

Results:

In Group 1, the C-section delivery rate was higher (82% vs. 44%; p = 0.004), and it was observed that patients in Group 1 were more often intubated upon admission to the neonatal ICU (38% vs. 9%; p = 0.005). No differences were found between the two groups in terms of operation time, cardiopulmonary bypass time, post-operative invasive respiratory support duration, or extracorporeal membrane oxygenation support. It was observed that those who had Taussig–Bing anomaly had a higher mortality.

Conclusions:

Timely treatment have a positive effect on neonatal mortality and morbidity. That’s why all families with prenatal diagnosis of critical CHD should be recommended to have the delivery in a tertiary care hospital. Although it could not be demonstrated in this study, prenatal diagnosis has a potential to improve surgical results especially in countries or cities, which does not have enough resources for transfer and surgical units. Further efforts are needed to improve prenatal screening programmes.
Efficacy and safety of endotracheal instillation of iloprost for persistent pulmonary hypertension of the newborn
Authors: Okbay Gunes Asli , Ciftel Murat , Timur Mehmet Emcet , Dedebali Ceren , Pirdal Betul Zehra
Published: January 2022

Objective:

To determine the efficacy and safety of endotracheal instillation of iloprost as a rescue therapy for persistent pulmonary hypertension of the newborn.

Methods:

Neonates diagnosed with persistent pulmonary hypertension who were unresponsive to standard treatment protocol applied for persistent pulmonary hypertension in our unit, and who were being followed up with mechanical ventilation, were included in the study. Iloprost was instilled endotracheally as a rescue treatment. Systolic pulmonary artery pressure, oxygen saturation index, mean airway pressure, fraction of inspired oxygen, preductal and postductal venous oxygen saturation, heart rate, and blood pressure were recorded before and after 30 minutes of endotracheal iloprost instillation. Adverse events after endotracheal iloprost were recorded.

Results:

Twenty neonates were included. The median gestational age and birth weight were found to be 37 (30.5-38) weeks and 2975 (2125-3437.5) grams, respectively. When compared to the period before endotracheal iloprost instillation, systolic pulmonary artery pressure, oxygen saturation index, mean airway pressure, and fraction of inspired oxygen values significantly decreased (p < 0.001, p < 0.001, p = 0.021, p = 0.001, respectively), whereas preductal and postductal oxygen saturation values significantly increased 30 minutes after the endotracheal iloprost instillation (p = 0.002, p < 0.001, respectively). There were no significant differences in heart rate and blood pressure values before and after the iloprost administration. No adverse events were observed.

Conclusion:

Endotracheal instillation of iloprost was found to be an effective and safe therapy for persistent pulmonary hypertension unresponsive to conventional treatment.
Propensity score analysis of the association between maternal exposure to second-hand tobacco smoke and birth defects in Northwestern China
Authors: Li Jing , Du Yujiao , Qu Fengyi , Jing Hui , Yan Hong , Dang Shaonong
Published: January 2022

Previous studies have suggested that maternal active smoking can increase the risk of birth defects, but evidence on second-hand tobacco smoke (SHS) is limited. We aimed to assess the association between maternal exposure to SHS and birth defects in a Chinese population. The data were based on a large-scale cross-sectional survey conducted in Shaanxi Province, China. Considering the characteristics of survey design and the potential impact of confounding factors, we adopted propensity score matching (PSM) to match the SHS exposure group and the non-exposure group to attain a balance of the confounders between the two groups. Subsequently, conditional logistic regression was employed to estimate the effect of SHS exposure on birth defects. Furthermore, sensitivity analyses were conducted to verify the key findings. After nearest neighbor matching of PSM with a ratio of 2 and a caliper width of 0.03, there were 6,205 and 12,410 participants in the exposure and control group, respectively. Pregnant women exposed to SHS were estimated to be 58% more likely to have infants with overall birth defects (OR = 1.58, 95% CI: 1.30–1.91) and 75% more likely to have infants with circulatory system defects (OR = 1.75, 95% CI: 1.26–2.44). We also observed that the risk effect of overall birth defects had an increasing trend as the frequency of exposure increased. Additionally, sensitivity analyses suggested that our results had good robustness. These results indicate that maternal exposure to SHS likely increases the risk of overall birth defects, especially circulatory system defects, in Chinese offspring.
Maternal BMI, breastfeeding and perinatal factors that influence early childhood growth trajectories: a scoping review
Authors: Abrego Del Castillo Kayla Y. , Dennis Cindy-Lee , Wamithi Susan , Briollais Laurent , McGowan Patrick O. , Dol Justine , Lye Stephen J.
Published: January 2022

Obesity rates among children are rapidly rising internationally and have been linked to noncommunicable diseases in adulthood. Individual preventive strategies have not effectively reduced global obesity rates, leading to a gap in clinical services regarding the development of early perinatal interventions. The objective of this scoping review is to explore the relationship between maternal BMI and breastfeeding behaviors on child growth trajectories to determine their relevance in developing interventions aimed at preventing childhood obesity.

The scoping review was guided and informed by the Arksey and O’Malley (2005) framework. A systematic search was performed in four databases. Studies included in the final review were collated and sorted into relevant themes. A systematic search yielded a total of 5831 records (MEDLINE: 1242, EMBASE: 2629, CINAHL: 820, PubMed: 1140). Results without duplicates (n = 4190) were screened based on relevancy of which 197 relevant-full-text articles were retrieved and assessed for eligibility resulting in 14 studies meeting the inclusion criteria. Data were extracted and charted for the studies and six themes were identified: (1) healthy behaviors, lifestyle, and social economic status; (2) parental anthropometrics and perinatal weight status; (3) genetics, epigenetics, and fetal programming; (4) early infant feeding; (5) infant growth trajectories; and (6) targeted prevention and interventions. Early life risk factors for child obesity are multifactorial and potentially modifiable. Several at-risk groups were identified who would benefit from early preventative interventions targeting the importance of healthy weight gain, exclusive breastfeeding to 6 months, and healthy lifestyle behaviors.
Effects of omega fatty acids on the short-term postprandial satiety related peptides in rats
Authors: Guldemir Hilal Hizli , Buyukuslu Nihal , Yigit Pakize , Cakici Cagri , Ozdemir Ekrem Musa
Published: January 2022

Abstract: We aimed to assess the effects of omega fatty acids on time depending on responses of satiety hormones. Sixty adult rats were randomly divided into 4 groups; linoleic acid (LA), α-linolenic acid (ALA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) groups. For each fatty acid, the dose of 400 mg/kg was applied by oral gavage. Blood samples were taken after the 15, 30, 60 and 120 minutes. Ghrelin, cholecystokinin (CCK), glucagon-like peptide-1 (GLP-1), peptide YY (PYY), leptin and insulin hormones were analyzed by ELISA. We observed the significant increases (p<0.05) of the levels of CCK between n-3 (ALA, at 60th min; EPA, at 30th and 60th min and DHA, at 60 min) and n-6 (LA) supplemented rats. The highest GLP-1 levels were in ALA (0.70 ng/mL) and DHA (0.67 ng/mL) supplemented groups at 60th and 120th min indicating n-3 fatty acids efficiency on satiety compared to LA. It seems that ALA at 60th min and EPA at 120th min could provide the highest satiety effect with the highest insulin response, while the efficiency of LA supplementation on insulin-induced satiety diminished. The only significant change in AUC values among all hormones was in the CCK of the ALA group (p=0.004). The level of leptin increased in DHA and EPA supplemented rats (p=0.140). Our results showed that dietary omega fatty acids influenced the releasing of hormones in different ways possibly depending on chain length or saturation degree. Comprehensive studies need to be addressed for each fatty acid on satiety-related peptide hormones.
Diurnal Variability in Aeolian Sediment Transport at Gale Crater, Mars
Authors: Baker Mariah M. , Newman Claire E. , Sullivan Robert , Minitti Michelle E. , Edgett Kenneth S. , Fey Deirdra , Ellison Doug , Lewis Kevin W.
Published: January 2022

A suite of high resolution cameras onboard the Mars Science Laboratory (MSL) Curiosity rover have provided an unparalleled look at active aeolian processes on Mars, including within the first active dune field explored on another planet, the Bagnold Dunes. Here we present results from a subset of MSL's repeat imaging (“change detection”) experiments with temporal resolutions sufficient to probe the diurnal variability in winds within Gale crater. Images reveal that saltation is a near‐daily phenomenon during southern summer, with repeatable diurnal circulation patterns producing steady impact ripple migration toward the west/southwest. Nighttime fluxes are inferred to be ∼four times larger than daytime fluxes, consistent with predictions from the MarsWRF model of multiple periods of enhanced wind between sunset and sunrise. Multiple factors are likely facilitating saltation at this time: (a) time‐averaged nighttime winds have a higher degree of variance (i.e., higher peak friction speeds) than daytime winds, (b) interactions between regional Hadley flows and local, thermally driven slope winds cause increased turbulence at night, and (c) relatively higher atmospheric density produces correspondingly higher shear stresses and decreases critical thresholds. Observations of sand transport at a range of spatiotemporal scales (down to scale of individual particles moving on the timescale of seconds) support the idea that bedform migration is driven by intermittent, low‐flux saltation events when winds fluctuate between canonical impact and fluid thresholds. Yet, whereas gustiness may play a role in initiating transport, saltation is found to be highly predictable on diurnal timescales and is only stochastic on the shortest timescales characteristic of turbulent fluctuations in wind.
Supporting Growth and Transpiration of Newly Planted Street Trees With Passive Irrigation Systems
Authors: Thom Jasmine K. , Fletcher Tim D. , Livesley Stephen J. , Grey Vaughn , Szota Christopher
Published: January 2022

Solutions that use stormwater runoff to rapidly establish tree canopy cover in cities have received significant attention. Passive irrigation systems that direct stormwater to trees have the potential to increase growth and transpiration and may limit drought stress. However, little data from the field demonstrates this, and we lack robust and reliable designs which achieve it. Here, we quantified growth and transpiration for trees: (a) in infiltration pits receiving stormwater, with a raised underdrain and internal water storage (drained), (b) next to infiltration pits receiving stormwater but without an underdrain and internal water storage (adjacent), and (c) planted in standard pits, not receiving stormwater (control). Trees in drained pits grew twice as fast as control trees in the first 2 years, but fast initial growth rates were not sustained in years three and four. Trees outgrowing the small infiltration pits, rather than a lack of water, was most likely responsible for growth rates slowing down. Despite this, rapid initial growth for trees in drained pits meant trees were larger by year three and transpired more than twice as much (5.1 L d−1) as trees adjacent to pits (2.4 L d−1) or control trees (2.3 L d−1). No trees showed drought stress during the study. However, some trees planted adjacent to infiltration pits showed waterlogging stress, suggesting caution installing infiltration pits adjacent to establishing trees in fine‐textured soils. Overall, our results suggest passive irrigation systems can substantially increase initial tree growth, thereby facilitating greater cooling and runoff reduction through increased transpiration.
Modeling the Varying Location of Field Line Resonances During Geomagnetic Storms
Authors: Elsden T. , Yeoman T. K. , Wharton S. J. , Rae I. J. , Sandhu J. K. , Walach M‐T. , James M. K. , Wright D. M.
Published: January 2022

Previous observational studies have shown that the natural Alfvén frequencies of geomagnetic field lines vary significantly over the course of a geomagnetic storm, decreasing by up to 50% from their quiet time values outside the plasmasphere. This was recently demonstrated statistically using ground magnetometer observations across 132 geomagnetic storm events (Wharton et al., 2020). This then brings into question where field line resonances (FLRs) will form in storm‐time conditions relative to quiet times. With storm‐time radiation belt dynamics depending heavily upon wave‐particle interactions, understanding how FLR locations change over the course of a storm will have important implications for this area. Using 3D magnetohydrodynamic (MHD) simulations, we investigate how changes in the Alfvén frequency continuum of the Earth's dayside magnetosphere over the course of a geomagnetic storm affect the fast‐Alfvén wave coupling. By setting the model Alfvén frequencies consistent with the observations, and permitting a modest change in the plasmapause/magnetopause locations consistent with storm‐time behavior, we show that FLR locations can change substantially during storms. The combined effects of higher fast waveguide frequencies and lower Alfvén frequencies during storm main phases, act together to move the FLR locations radially inwards compared to quiet times. FLRs outside of the plasmasphere are moved radially inward by 1.7 Earth radii for the cases considered.
A Fast Bow Shock Location Predictor‐Estimator From 2D and 3D Analytical Models: Application to Mars and the MAVEN Mission
Authors: Simon Wedlund Cyril , Volwerk Martin , Beth Arnaud , Mazelle Christian , Möstl Christian , Halekas Jasper , Gruesbeck Jacob R. , Rojas‐Castillo Diana
Published: January 2022

We present fast algorithms to automatically estimate the statistical position of the bow shock from spacecraft data, using existing analytical two‐dimensional (2D) and three‐dimensional (3D) models of the shock surface. We derive expressions of the standoff distances in 2D and 3D and of the normal to the bow shock at any given point on it. Two simple bow shock detection algorithms are constructed, one solely based on a geometrical predictor from existing models, the other using this predicted position to further refine it with the help of magnetometer data, an instrument flown on many planetary missions. Both empirical techniques are applicable to any planetary environment with a defined shock structure. Applied to the Martian environment and the NASA/MAVEN mission, the predicted shock position is on average within 0.15 planetary radius Rp of the bow shock crossing. Using the predictor‐corrector algorithm, this estimate is further refined to within a few minutes of the true crossing (≈0.05Rp). Between 2014 and 2021, we detect 14,929 clear bow shock crossings, predominantly quasi‐perpendicular. Thanks to 2D conic and 3D quadratic fits, we investigate the variability of the shock surface with respect to Mars Years (MY), solar longitude (Ls), and solar EUV flux levels. Although asymmetry in Y and Z Mars Solar Orbital coordinates is on average small, we show that for MY32 and MY35, Ls = [135°−225°] and high solar flux, it can become particularly noticeable, and is superimposed to the usual North‐South asymmetry due in part to the presence of crustal magnetic fields.
Global Distribution of Concurrent EMIC Waves and Magnetosonic Waves: A Survey of Van Allen Probes Observations
Authors: Zhou Ruoxian , Ni Binbin , Fu Song , Teng Shangchun , Tao Xin , Hu Zejun , Guo Jianguang , Hua Man , Yi Juan , Guo YingJie , Jiao Luhuai , Ma Xin , Gu Xudong
Published: January 2022

Recent studies have reported the simultaneous observation of Magnetosonic (MS) waves and Electromagnetic ion cyclotron (EMIC) waves. In this study, a detailed survey of the concurrent EMIC waves and MS waves is performed using the Van Allen Probes observations from 2012 to 2017. The results suggest that most of the concurrent EMIC waves and MS waves are H+ band EMIC waves and MS waves. The favorable geomagnetic conditions for the concurrent EMIC waves and MS waves are AE* ≥ 500 nT inside the plasmapause and AE* ≥ 100 nT outside the plasmapause. Although EMIC waves are generally stronger than MS waves, stronger MS waves than EMIC waves are more likely to occur during moderate and active geomagnetic times. Our study is consistent with the most recent research, and provides more detailed information that helps us to deepen our understanding of the concurrent EMIC waves and MS waves.
Pn Anisotropic Tomography of Northeast Asia: New Insight Into Subduction Dynamics and Volcanism
Authors: Du Mofei , Lei Jianshe , Zhao Dapeng , Lu Hongbin
Published: January 2022

We present a new high‐resolution model of P‐wave anisotropic tomography of the uppermost mantle beneath NE Asia obtained by inverting 88,303 high‐quality manually picked Pn arrival times. Our model reveals strong lateral heterogeneities in both isotropic velocity and azimuthal anisotropy. Distinct high Pn velocities are visible under the basins in NE China, and eastern and western Japan basins. Very high Pn velocities with trench‐normal fast Pn anisotropy are revealed near the Kurile‐Japan trench, representing the incoming Pacific plate. Prominent low Pn velocity anomalies are revealed under active intraplate volcanoes in NE China and arc volcanoes on the Japan Islands. Very low Pn velocities with trench‐parallel fast Pn anisotropy are observed along the volcanic front in Japan, reflecting compressed mantle flows. An NW‐SE oriented low‐velocity (low‐V) zone from the Wudalianchi volcano to the Changbaishan volcano meets the E‐W oriented low‐V zone around the Changbaishan volcano and the N‐S low‐V zone east of the Sanjiang basin, which converge to a broad N‐S low‐V zone. This zone passes through the central Japan basin to the junction of the Japan and Izu‐Bonin trenches, where it meets the nearly E‐W low‐V zone from the Changle volcano. These low‐V anomalies exhibit zone‐parallel fast Pn anisotropy and may indicate channels for material and energy exchanges among the volcanoes, driven by mantle flows in the big mantle wedge. These results provide new insights into interplate and intraplate volcanism and subduction dynamics in the study region.
Spatiotemporal Variability of Aragonite Saturation State in the Northern East China Sea
Authors: Choi Yujeong , Kim Tae‐Hoon , Kim Dongseon , Kang Dong‐Jin
Published: January 2022

In order to evaluate the spatiotemporal distribution of the carbonate system in the northern East China Sea (ECS), we first measured the seasonal dissolved inorganic carbon (DIC) and total alkalinity (TA), from which the aragonite saturation state (Ωarag) was calculated for the years 2015–2017. The DIC, TA, and Ωarag were 1,680.9–2,211.4 μmol kg−1, 2,145.1–2,312.8 μmol kg−1, and 1.2–6.0, respectively. The spatiotemporal variability of Ωarag in the northern ECS was mainly controlled by seasonal water mass, such as Yellow Sea Surface Water, Changjiang Dilute Water, and Yellow Sea Bottom Water (YSBW). The lowest Ωarag (∼1.4) in bottom layer was observed in high primary production areas caused by the extension of the Changjiang River plume with the higher Ωarag (up to 6) and was closely linked to the YSBW with low Ωarag expanded southward from Yellow Sea near bottom. Although this area was not a hypoxia zone unlike western shelf region (Chinese region) of the northern ECS, YSBW near bottom could enhance the suppression of bottom aragonite without hypoxia. In eastern region of northern ECS, higher production at surface, YSBW with lower Ωarag extension, and longer respiration product accumulations near bottom tend to lower Ωarag, as compared with western region where the summer hypoxia led to lower Ωarag. Therefore, this result indicates that the eastern region of the northern ECS is also susceptible to ocean acidification, along with the summer hypoxic zone of the western region.
Reduction in Anthropogenic Emissions Suppressed New Particle Formation and Growth: Insights From the COVID‐19 Lockdown
Authors: Kanawade V. P. , Sebastian M. , Dasari P.
Published: January 2022

To control the spread of the novel 2019 Coronavirus (COVID‐19), the Government of India enforced nationwide social and transportation restrictions (lockdown) in three phases from the evening of 24 March to 31 May 2020, which resulted in a significant reduction of primary emissions. Here, we performed the analyses of particle number size distribution measurements in the particle size range of 1.2–3 nm and 10–514 nm carried out from 15 April to 31 May 2020 (lockdown, LCD) and compared with measurements from the previous year during the same time period (15 April to 31 May 2019, business‐as‐usual, BAU) at University of Hyderabad in Hyderabad, India. The number concentrations of sub‐3 nm particles were comparable between LCD and BAU, but the number concentrations of particles greater than 10 nm diameter were lower by about 85% during LCD than BAU. It indicates that the reduction in primary anthropogenic emissions did not inhibit the formation of sub‐3 nm particles. But the frequency of occurrence of the new particle formation and growth (NPF&G) events was three‐fold lower during LCD than BAU. The ratio of formaldehyde to nitrogen dioxide indicated that India falls in a NOx‐limited regime, which reduces ambient ozone concentrations (lower condensable vapors via ozone oxidation of volatile organic compounds). Besides, the lower temperature (lower hydroxyl radical concentration) and lower wind speed during LCD may have contributed to the suppression of NPF&G events. Therefore, we emphasize the need to account for processes and interactions related to NPF&G in formulating particulate pollution mitigation policies in urban environments.
Multi‐Season Evaluation of CO2 Weather in OCO‐2 MIP Models
Authors: Zhang Li , Davis Kenneth J. , Schuh Andrew E. , Jacobson Andrew R. , Pal Sandip , Cui Yu Yan , Baker David , Crowell Sean , Chevallier Frederic , Remaud Marine , Liu Junjie , Weir Brad , Philip Sajeev , Johnson Matthew S. , Deng Feng , Basu Sourish
Published: January 2022

The ability of current global models to simulate the transport of CO2 by mid‐latitude, synoptic‐scale weather systems (i.e., CO2 weather) is important for inverse estimates of regional and global carbon budgets but remains unclear without comparisons to targeted measurements. Here, we evaluate ten models that participated in the Orbiting Carbon Observatory‐2 model intercomparison project (OCO‐2 MIP version 9) with intensive aircraft measurements collected from the Atmospheric Carbon Transport (ACT)‐America mission. We quantify model‐data differences in the spatial variability of CO2 mole fractions, mean winds, and boundary layer depths in 27 mid‐latitude cyclones spanning four seasons over the central and eastern United States. We find that the OCO‐2 MIP models are able to simulate observed CO2 frontal differences with varying degrees of success in summer and spring, and most underestimate frontal differences in winter and autumn. The models may underestimate the observed boundary layer‐to‐free troposphere CO2 differences in spring and autumn due to model errors in boundary layer height. Attribution of the causes of model biases in other seasons remains elusive. Transport errors, prior fluxes, and/or inversion algorithms appear to be the primary cause of these biases since model performance is not highly sensitive to the CO2 data used in the inversion. The metrics presented here provide new benchmarks regarding the ability of atmospheric inversion systems to reproduce the CO2 structure of mid‐latitude weather systems. Controlled experiments are needed to link these metrics more directly to the accuracy of regional or global flux estimates.
How Do Perceptions of Risk Communicator Attributes Affect Emergency Response? An Examination of a Water Contamination Emergency in Boston, USA
Authors: Hyman Amy , Arlikatti Sudha , Huang Shih‐Kai , Lindell Michael K. , Mumpower Jeryl , Prater Carla S. , Wu Hao‐Che
Published: January 2022

A water main break that contaminated the Boston area's water distribution system prompted a four‐day “boil water” order. To understand risk communication during this incident, 600 randomly sampled residents were mailed questionnaires, yielding 110 valid responses. This article describes how perceptions of different social stakeholders influenced whether respondents complied with the Protective Action Recommendation—PAR (i.e., drank boiled water), took alternative protective actions (i.e., drank bottled water or/and self‐chlorinated water), or ignored the threat (i.e., continued to drink untreated tap water). Respondents perceived technical authorities (i.e., water utility, public health, and emergency management) to be higher on three social influence attributes (hazard expertize, trustworthiness, and protection responsibility) than public (i.e., news media, elected officials) and private (i.e., self/family, peers, and personal physicians) intermediate sources. Furthermore, respondents were most likely to comply with the PAR if they perceived authorities and public intermediates to be high on all three attributes and if they had larger households and lower income. Contrarily, they were more likely to take alternative actions if they were younger and had higher levels of income, risk perception, and emergency preparedness. These results underscore the need for technical authorities to develop credibility with their potential audiences before a crisis occurs.
Lasting Effects of Soil Compaction on Soil Water Regime Confirmed by Geoelectrical Monitoring
Authors: Romero‐Ruiz Alejandro , Linde Niklas , Baron Ludovic , Breitenstein Daniel , Keller Thomas , Or Dani
Published: January 2022

Despite its importance for hydrological and ecological soil functioning, characterizing, and quantifying soil structure in the field remains a challenge. Traditional characterization of soil structure often relies on point measurements, more recently, we advanced the use of minimally invasive geophysical methods that operate at plot‐field scales and provide information under natural conditions. In this study, we expand the application using geoelectrical and time‐domain reflectometry (TDR) monitoring of soil water dynamics to infer impacts of compaction on soil structure and function. We developed a modeling scheme combining a new pedophysical model of soil electrical conductivity and a soil‐structure‐informed one‐dimensional water flow and heat‐transfer model. The model was used to interpret Direct Current (DC)‐resistivity and TDR monitoring data in compacted soils at the Soil Structure Observatory (SSO) located in the vicinity of Zürich, Switzerland. We find that (1) soil compaction leads to a persistent decrease in soil electrical resistivity and (2) that compacted soils are typically drier than non‐compacted soils during long drying events. The main decrease in electrical resistivity is attributed to decreasing macroporosity and increasing connectivity of soil aggregates due to compaction. Higher water losses in compacted soils are explained in terms of enhanced evaporation. Our work advances characterization of soil structure at the field scale with electrical methods by offering a physically based explanation of the impact of soil compaction on electrical properties and by interpreting DC‐resistivity data in terms of soil water dynamics.
Architecture engineering of nanostructured catalyst via layer-by-layer adornment of multiple nanocatalysts on silica nanorod arrays for hydrogenation of nitroarenes
Authors: Hong Kootak , Suh Jun Min , Lee Tae Hyung , Cho Sung Hwan , Ramakrishna Seeram , Varma Rajender S. , Jang Ho Won , Shokouhimehr Mohammadreza
Published: January 2022

Direct consideration for both, the catalytically active species and the host materials provides highly efficient strategies for the architecture design of nanostructured catalysts. The conventional wet chemical methods have limitations in achieving such unique layer-by-layer design possessing one body framework with many catalyst parts. Herein, an innovative physical method is presented that allows the well-regulated architecture design for an array of functional nanocatalysts as exemplified by layer-by-layer adornment of Pd nanoparticles (NPs) on the highly arrayed silica nanorods. This spatially confined catalyst exhibits excellent efficiency for the hydrogenation of nitroarenes and widely deployed Suzuki cross-coupling reactions; their facile separation from the reaction mixtures is easily accomplished due to the monolithic structure. The generality of this method for the introduction of other metal source has also been demonstrated with Au NPs. This pioneering effort highlights the feasibility of physically controlled architecture design of nanostructured catalysts which may stimulate further studies in the general domain of the heterogeneous catalytic transformations.