bluuebunny/crossref_metadata_2025 huggingface dataset:
Frequency of Pornography Use and Sexual Health Outcomes in Sweden: Analysis of a National Probability Survey
Authors: Malki Kinda , Rahm Christoffer , Öberg Katarina Görts , Ueda Peter
Published: September 2021

Background

Little is known about pornography use and its relationship with sexual health outcomes in the general population.

Aim

To assess frequency of pornography use and the association of sexual health outcomes with frequent pornography use in Sweden.

Methods

Cross-sectional analysis of 14,135 participants (6,169 men and 7,966 women) aged 16–84 years in a Swedish nationally representative survey from 2017. We used logistic regression to assess the association of sexual health outcomes with use of pornography ≥3 times/wk.

Outcomes

Frequency of pornography use (never; less than once/mo to 3 times/mo; 1–2 times/wk; 3–5 times/wk; and daily or almost daily) and sexual health outcomes (eg, sexual satisfaction and sexual health problems).

RESULTS

In total, 68.7% of men and 27.0% of women used pornography. Among men aged 16–24 years, 17.2% used pornography daily or almost daily, 24.7% used pornography 3–5 d/wk and 23.7% used pornography 1–2 d/wk. Among women aged 16–24 years, the proportions were 1.2% for daily or almost daily, 3.1% for 3–5 times/wk, and 8.6% for 1–2 times/wk. Frequency of pornography use decreased with age among both men and women. While 22.6% of all men and 15.4% of all women reported that their or a sex partner’s pornography use predominantly had positive effects on their sex life, 4.7% of men and 4.0% of women reported that the effects were predominantly negative. Variables indicating sexual dissatisfaction and sexual health problems were associated with use of pornography ≥3 times/wk: for example, dissatisfaction with sex life (age-adjusted odds ratio [aOR]: men 2.90 [95% CI 2.40–3.51]; women 1.85 [95% CI 1.09–3.16]), not having sex in the preferred way (aOR: men 2.48 [95% CI 1.92–3.20]; women 3.59 [95% CI 2.00–6.42]) and erection problems (aOR: men 2.18 [95% CI 1.73–2.76]).

Clinical Implications

While frequent pornography use is common, potential effects on sexual health outcomes are likely to differ between individuals.

Strength & Limitations

We used a large and recent nationally representative survey with detailed information regarding frequency of pornography use. The temporality of associations of sexual health variables with frequency of pornography use could not be assessed.

CONCLUSION

In this analysis of a nationally representative survey in Sweden, we found that frequent pornography use was common among young men; that reporting predominantly positive effects of pornography use on the sex life was more common than reporting predominantly negative effects; and that sexual dissatisfaction and sexual health problems were associated with using pornography ≥3 times/wk.
An Invitation to Combinatorics
Authors: Shahriari Shahriar
Published: September 2021

Active student engagement is key to this classroom-tested combinatorics text, boasting 1200+ carefully designed problems, ten mini-projects, section warm-up problems, and chapter opening problems. The author – an award-winning teacher – writes in a conversational style, keeping the reader in mind on every page. Students will stay motivated through glimpses into current research trends and open problems as well as the history and global origins of the subject. All essential topics are covered, including Ramsey theory, enumerative combinatorics including Stirling numbers, partitions of integers, the inclusion-exclusion principle, generating functions, introductory graph theory, and partially ordered sets. Some significant results are presented as sets of guided problems, leading readers to discover them on their own. More than 140 problems have complete solutions and over 250 have hints in the back, making this book ideal for self-study. Ideal for a one semester upper undergraduate course, prerequisites include the calculus sequence and familiarity with proofs.
Biopolitical Futures in Twenty-First-Century Speculative Fiction
Authors: Vint Sherryl
Published: September 2021

Drawing on a rich array of twenty-first-century speculative fiction, this book demonstrates how the commodification of life through biotechnology has far-reaching implications for how we think of personhood, agency, and value. Sherryl Vint argues that neoliberalism is reinventing life under biocapital. She offers new biopolitical figurations that can help theoretically grasp and politically respond to a distinctive twenty-first-century biopolitics. This book theorizes how biotechnology intervenes in the very processes of biological function, reshaping life itself to serve economic ends. Linking fictional texts with material examples, Biopolitical Futures in Twenty-First-Century Speculative Fiction shows how these practices are linked to new modes of exploitative economic relations that cannot be redressed by human rights. It concludes with a posthumanist reframing of the value of life that grounds itself elsewhere than in capitalist logics, a vision that, in a Covid age, might become fundamental to a new politics of ecological relations.
MORE ON THE PRESERVATION OF LARGE CARDINALS UNDER CLASS FORCING
Authors: BAGARIA JOAN , POVEDA ALEJANDRO
Published: September 2021

We prove two general results about the preservation of extendible and
$C^{(n)}$
-extendible cardinals under a wide class of forcing iterations (Theorems 5.4 and 7.5). As applications we give new proofs of the preservation of Vopěnka’s Principle and
$C^{(n)}$
-extendible cardinals under Jensen’s iteration for forcing the GCH [17], previously obtained in [8, 27], respectively. We prove that
$C^{(n)}$
-extendible cardinals are preserved by forcing with standard Easton-support iterations for any possible
$\Delta _2$
-definable behaviour of the power-set function on regular cardinals. We show that one can force proper class-many disagreements between the universe and HOD with respect to the calculation of successors of regular cardinals, while preserving
$C^{(n)}$
-extendible cardinals. We also show, assuming the GCH, that the class forcing iteration of Cummings–Foreman–Magidor for forcing
$\diamondsuit _{\kappa ^+}^+$
at every
$\kappa $
[10] preserves
$C^{(n)}$
-extendible cardinals. We give an optimal result on the consistency of weak square principles and
$C^{(n)}$
-extendible cardinals. In the last section prove another preservation result for
$C^{(n)}$
-extendible cardinals under very general (not necessarily definable or weakly homogeneous) class forcing iterations. As applications we prove the consistency of
$C^{(n)}$
-extendible cardinals with
$\mathrm {{V}}=\mathrm {{HOD}}$
, and also with
$\mathrm {GA}$
(the Ground Axiom) plus
$\mathrm {V}\neq \mathrm {HOD}$
, the latter being a strengthening of a result from [14].
Previous herbivory modulates aphid population growth and plant defense responses in a non-model plant,Carthamus tinctorius(Asteraceae)
Authors: Amiri Domari Motahareh , Mansouri Seyed Mozaffar , Mehrparvar Mohsen
Published: September 2021

Plants have a variety of defense mechanisms that are often induced following attacks by herbivores; this benefits those plants by decreasing performance or preference of herbivores that attack the plants later. We investigated the effects of previous exposure of plants to the safflower aphid,Uroleucon carthami, cotton bollworm,Helicoverpa armigera, and mechanical wounding on subsequent safflower aphid infestations using commercial safflower (Carthamus tinctorius) cultivars and wild safflower species (C. oxyacantha). The experiments were conducted in a greenhouse with two treatments: previously induced plants via direct herbivory or mechanical wounding, and control plants that had never experienced herbivory. To test the performance of safflower aphid on different plant treatments, five unwinged aphids were placed on each plant and allowed to reproduce for 14 days. Finally, the total numbers of aphids on each plant were counted and the percentage of produced winged individuals was calculated. The number of aphids on plants that were previously infested or injured was significantly lower than in control plants. Percentage of winged aphids was significantly higher on induced plants, which is an indicator for unsuitable conditions. Also, significant increase in total phenolic content and hydrogen peroxide was observed in induced plants, showing that the levels of these compounds were either treatment, cultivar and/or genotype × treatment dependent, highlighting the specificity of these interactions. Overall, among the safflower cultivars the lowest number of aphids and the highest percentage of winged aphid individuals were observed on Mahali-Isfahan cultivar and wild safflower, showing that this cultivar is more sensitive to herbivory and/or responds to it more than other cultivars. These findings could contribute to a better utilization of induced defense in the integrated pest management of safflower fields.
A meta-analysis of theory of mind and ‘mentalization’ in borderline personality disorder: a true neuro-social-cognitive or meta-social-cognitive impairment?
Authors: Bora Emre
Published: September 2021

Background

It is widely accepted that borderline personality disorder (BPD) is associated with significant impairments in mentalization and theory of mind (ToM) which are considered as closely related concepts by many authors particularly in psychoanalytical circles. However, for understanding interpersonal difficulties in personality disorders, it is important to distinguish neuro-social cognitive impairment from the abnormal meta-social-cognitive style of patients.

Methods

The current systematic review aimed to conduct separate meta-analyses of ‘mentalization’ [reflective functioning (RF] and different aspects of ToM in BPD. A literature search was conducted to locate relevant articles published between January 1990 to July 2021. Random-effect meta-analyses were conducted in 34 studies involving 1448 individuals with BPD and 2006 healthy controls.

Results

A very large impairment in RF was evident in BPD [d = 1.68, confidence interval (CI) = 1.17–2.19]. In contrast, ToM impairment was modest (d = 0.36, CI = 0.24–0.48). BPD patients underperformed healthy controls in ToM-reasoning (d = 0.44, CI = 0.32–0.56) but not ToM-decoding. Increased HyperToM (d = 0.60, CI = 0.41–0.79) and faux pas recognition (d = 0.62, CI = 0.35–0.90) errors in BPD compared to healthy controls were most robust ToM findings in this meta-analysis.

Conclusions

BPD is characterized by very severe deficits in RF and modest and selective abnormalities in ToM. Interpersonal problems and difficulties in processing social information in BPD can be best explained by patients' maldaptive meta-social cognitive style and top-down effects of these abnormalities rather than having a primary neuro-social cognitive deficit.
ON COMPLEXITY AND DIVERGENCE IN HERITAGE LANGUAGE GRAMMARS
Authors: Perez-Cortes Silvia
Published: September 2021

For more than a decade, research on heritage speakers’ (HSs’) mood selection has documented a high degree of variability in their interpretation and use of mood morphology in variable contexts. Most of the previous literature, however, has focused on late-acquired alternations, and often limited analyses to one form (i.e., subjunctive), making it difficult to draw conclusions about HSs’ knowledge of mood distinctions. This study intends to fill this gap by examining Spanish HSs’ (n =76) and Spanish-dominant controls’ (n =25) interpretation and use of an early acquired mood alternation, where the presence of indicative or subjunctive conveys the report of an assertion or a command. Results from two experimental tasks reveal that, even though HSs’ performance tends to differ from that of controls’—especially at lower levels of proficiency—the nature and extent of their divergences suggests the need to embrace a more nuanced analysis of HSs’ linguistic outcomes when examining modal contrasts.
Ultra-processed food consumption, socio-demographics and diet quality in Australian adults
Authors: Marchese Laura , Livingstone Katherine M , Woods Julie L , Wingrove Kate , Machado Priscila
Published: September 2021

Objective:

To examine how socio-demographic characteristics and diet quality vary with consumption of ultra-processed foods (UPF) in a cross-sectional nationally representative survey of Australian adults.

Design:

Using a 24-h recall, this cross-sectional analysis of dietary and socio-demographic data classified food items using the NOVA system, estimated the percentage of total energy contributed by UPFs and assessed diet quality using the Dietary Guideline Index (DGI–2013 total and components). Linear regression models examined associations between socio-demographic characteristics and diet quality with percentage of energy from UPF.

Setting:

Australian Health Survey 2011–2013.

Participants:

Australian adults aged ≥ 19 years (n 8209).

Results:

Consumption of UPF was higher among younger adults (aged 19–30 years), adults born in Australia, those experiencing greatest area-level disadvantage, lower levels of education and the second lowest household income quintile. No significant association was found for sex or rurality. A higher percentage of energy from UPF was inversely associated with diet quality and with lower DGI scores related to the variety of nutritious foods, fruits, vegetables, total cereals, meat and poultry, fish, eggs, nuts and seeds, legumes/beans, water and limits on discretionary foods, saturated fat and added sugar.

Conclusions:

This research adds to the evidence on dietary inequalities across Australia and how UPF are detrimental to diet quality. The findings can be used to inform interventions to reduce UPF consumption and improve diet quality.
What is known about human milk bank donors around the world: a systematic scoping review
Authors: Gutierrez dos Santos Bruna , Perrin Maryanne T
Published: September 2021

Objective:

The WHO recommends that low birth weight infants receive donor human milk (DHM) when mother’s milk is not available. Systematic reviews have been published regarding clinical outcomes of infants receiving DHM, as well as the impact of pasteurisation on the composition of DHM; however, information about milk bank donors has not been systematically assessed.

Design:

We conducted a systematic scoping review of original research articles about milk bank donors published before August 2020.

Setting:

Globally.

Participants:

Donors to milk banks.

Results:

A total of twenty-eight studies were included across a variety of geographies: the USA (n 8), Brazil (n 7), Spain (n 4), India (n 2), and single studies in France, Norway, Poland, Italy, Taiwan, Korea and China. Study variables were grouped into six main categories: Donor Demographics (n 19), Clinical Characteristics (n 20), Donor Experiences (n 16), Donation Patterns (n 16), Lifestyle Characteristics (n 4) and Lactation/Breast-feeding History (n 8). Some demographic characteristics were commonly reported across regions, while other, including gender and race, were infrequently explored. Factors that might influence the composition of DHM, including birth timing (term or pre-term), milk type (colostrum, transition or mature) and maternal diet were not regularly studied. Other gaps in the literature included (1) donors’ motivations and barriers to donation, (2) lactation and breast-feeding history, including factors that influence donors to pump and amass surplus milk, and (3) donation patterns, including whether donors are also selling milk to corporations or sharing milk with peers.

Conclusion:

What is known about milk bank donors in different geographies is often limited to a single study, with heterogeneity in the variables reported.
Pricing insurance policies with offsetting relationship
Authors: Hanbali Hamza
Published: September 2021

This paper investigates the benefits of incorporating diversification effects into the pricing process of insurance policies from two different business lines. The paper shows that, for the same risk reduction, insurers pricing policies jointly can have a competitive advantage over those pricing them separately. However, the choice of competitiveness constrains the underwriting flexibility of joint pricers. The paper goes a step further by modelling explicitly the relationship between premiums and the number of customers in each line. Using the total collected premiums as a criterion to compare the competing strategies, the paper provides conditions for the optimal pricing decision based on policyholders’ sensitivity to price discounts. The results are illustrated for a portfolio of annuities and assurances. Further, using non-life data from the Brazilian insurance market, an empirical exploration shows that most pairs satisfy the condition for being priced jointly, even when pairwise correlations are high.
Spatiotemporal Characterization of Mercury Isotope Baselines and Anthropogenic Influences in Lake Sediment Cores
Authors: Lee Ju Hyeon , Kwon Sae Yun , Yin Runsheng , Motta Laura C. , Kurz Aaron Y. , Nam Seung‐Il
Published: September 2021

Increasing mercury isotope ratios from pre‐industrial (1510–1850) to present‐day (1990–2014) in lake sediment cores have been suggested to be a global phenomenon. To assess factors leading to spatiotemporal changes, we compiled mercury concentration (THg) and mercury isotope ratios in 22 lake sediment cores located at various regions of the world. We find that the positive δ202Hg shifts together with THg increases from pre‐industrial to present‐day are a widespread phenomenon. This is caused by increased contribution of mercury from local to regional anthropogenic mercury emission sources, which lead to higher sediment δ202Hg (−1.07 ± 0.69‰, 1 SD) than pre‐industrial sediments (−1.55 ± 0.96‰, 1 SD). The positive Δ199Hg shifts were observed in 15 lake sediment cores, which have low pre‐industrial Δ199Hg (−0.20 ± 0.32‰) compared to the sediment cores with near‐zero to positive pre‐industrial Δ199Hg (0.08 ± 0.07‰). The magnitudes of δ202Hg (r2 = 0.09) and Δ199Hg (r2 = 0.20, both p > 0.05) changes from pre‐industrial to present‐day did not correlate with the magnitude of THg changes. Instead, the magnitudes of δ202Hg and Δ199Hg changes decreased with increasing pre‐industrial δ202Hg and Δ199Hg values, suggesting that the baseline mercury isotope ratios play a more important role in determining the magnitude of mercury isotope changes compared to the degree of THg input. We suggest that the spatiotemporal assessments of δ202Hg in lake sediment cores can be used as an important proxy for monitoring changes in anthropogenic mercury sources for the Minamata Convention on Mercury.
Upward‐Doming Zones of Gas Hydrate and Free Gas at the Bases of Gas Chimneys, New Zealand's Hikurangi Margin
Authors: Crutchley G. J. , Mountjoy J. J. , Hillman J. I. T. , Turco F. , Watson S. , Flemings P. B. , Davy B. , Woelz S. , Gorman A. R. , Bialas J.
Published: September 2021

Focused gas migration through the gas hydrate stability zone in vertical gas conduits is a global phenomenon. The process can lead to concentrated gas hydrate formation and seafloor gas seepage, which influences seafloor biodiversity and ocean biogeochemistry. However, much is unknown about how gas and gas hydrate co‐exist within and around gas conduits. We present seismic imaging of the gas hydrate system beneath a four‐way closure anticlinal ridge at New Zealand's southern Hikurangi subduction margin. Gas has accumulated beneath the base of gas hydrate stability to a thickness of up to ∼240 m, which has ultimately led to hydraulic fracturing and propagation of a vertical gas conduit to the seafloor. Despite the existence of an array of normal faults beneath the ridge, these structures are not exploited as long‐range gas flow conduits. Directly beneath the conduit, and extending upward from the regional base of gas hydrate stability, is a broad zone characterized by both negative‐ and positive‐polarity reflections. We interpret this zone as a volume of sediment hosting both gas hydrate and free gas, that developed due to partial gas trapping beneath a mass transport deposit. Similar highly reflective zones have been identified at the bases of other gas conduits, but they are not intrinsic to all gas conduits through gas hydrate systems. We suggest that pronounced intervening sealing units within the gas hydrate stability zone determine whether or not they form.
Laboratory Measurements of the Impact of Fracture and Fluid Properties on the Propagation of Krauklis Waves
Authors: Cao Haitao , Nakagawa Seiji , Askari Roohollah
Published: September 2021

The Krauklis wave is a slow dispersive wave, generated in fluid‐filled fractures. By analyzing the resonant frequency and quality factor of the Krauklis wave, the fracture dimension and fluid properties can be estimated. However, the accuracy of the estimation of fracture dimension and fluid properties depends on deciphering factors affecting the Krauklis wave such as fluid viscosity, fracture geometry, fracture compliance, and stiffness ratio, some of which have not been experimentally studied yet. We have developed an experimental apparatus to study the Krauklis wave within a trilayer model consisting of a pair of aluminum plates and a mediating viscous fluid layer. We utilize a piezoelectric source and miniature pressure transducers in our measurements. To evaluating the effects of the fracture aperture and fluid viscosity, we examine the impact of complex and realistic fracture geometry by introducing spatially varying aperture, surface roughness, and compliant partial surface contact provided by springs. The phase velocity, resonant frequencies, and quality factors (a) increase with the expansion of fracture aperture and (b) decrease with the increase of the fluid viscosity. Additionally, (c) phase velocity, resonant frequencies, and attenuation decrease with the increase of mechanical compliance. Furthermore, rough and wedge‐shaped fracture surfaces tend to slow down the Krauklis wave. Since the Krauklis wave is used by different disciplines such as volcanology, glaciology, and the petroleum industry to characterize fracture dimensions and properties of the fluids involved, our experimental findings can be used as a benchmark to develop comprehensive theoretical models to better interpret the Krauklis waves.
Numerical Simulation on the Effects of the Horizontal Charge Distribution on Lightning Types and Behaviors
Authors: Xu Dewang , Tan Yongbo , Zheng Tianxue , Lin Hui , Shi Zheng , Lei Yinan , Liu Minzhi , Wang Haichao , Yu Junhao
Published: September 2021

Previous studies have generally acknowledged that lightning propagation behaviors and lightning types are closely related to the unbalanced charge amount and vertical stratification of charge structure. In this study, the total charge amount remains nearly balanced (±5%) between the adjacent charge regions where discharges initiate to avoid the interference of a total charge imbalance. Significant influences on the leader propagation tendency and lightning type are revealed by investigating different horizontal charge distribution features emphasizing on the effects of the charge distribution uniformity and the relative position of the high‐density charge center. Sensitivity experiments are performed with a two‐dimensional stochastic discharge model and demonstrate the following. Under a symmetric charge distribution, the more uniform charge distribution is conducive for leaders propagate horizontally; the charge being more compact in the central zone is favorable for vertical extension of leaders. Under an asymmetric charge distribution, a horizontal shift of high‐density charge center is conducive to the extension of leaders in the offset direction. Different charge distributions will change the electrical energy of charge regions resulting in various lightning behaviors. Various charge distributions provide favorable conditions for some lightning flashes (including positive cloud‐to‐ground flashes [PCG], “bolt‐from‐the‐blue” [BFB] flashes and gigantic jets). PCGs are favorably triggered with the more compact upper positive charge (P) and more uniform middle negative charge (N), and BFB discharges can be triggered between the P and N regions when the high‐density charge center in the P region is horizontally shifted. A possible method is provided to explain various lightning behaviors.
Changes in Unevenness of Wet‐Day Precipitation Over China During 1961–2020
Authors: Han Jingya , Miao Chiyuan , Duan Qingyun , Wu Jingwen , Gou Jiaojiao , Zheng Haiyan
Published: September 2021

Precipitation falls unevenly in space and time, which has significant consequences for human society and natural ecosystems. Based on 2,134 gauged observations during 1961–2020 and historical simulations of 14 models participating in the Coupled Model Intercomparison Project Phase 6 (CMIP6), we analyze precipitation unevenness over China in terms of the spatiotemporal distribution of wet days (>1 mm) and wet‐day precipitation amount throughout the year. We also explore precipitation extremes related to the unevenness. Spatially, precipitation shows medium unevenness in China. Temporally, the unevenness in distribution of wet days increases from southeast (generally humid) to northwest (generally arid). This temporal unevenness weakened in large parts of western China during 1991–2020 relative to 1961–1990. As for precipitation amount, the distribution of precipitation that falls on wet days is more uneven in water‐limited regions compared with humid regions. Associated with this unevenness, between 1961 and 2020, the top 50% of annual precipitation fell in approximately the 12 wettest days, and the maximum 1‐day precipitation for the year contributed 10% on average to annual precipitation. The period 1991–2020 shows overall greater unevenness in eastern China and less unevenness in western China relative to the first 30 years. Multimodel ensemble means of CMIP6 simulations agree with the basic spatial pattern of observations, while underestimating the magnitude of temporal unevenness of precipitation. If these regional differences in precipitation unevenness were to persist over time, this would likely create some new challenges for water resource management in these areas, e.g., flash drought.
Description of Dust Emission Parameterization in CAS‐ESM2 and Its Simulation of Global Dust Cycle and East Asian Dust Events
Authors: Wu Chenglai , Lin Zhaohui , Liu Xiaohong , Ji Duoying , Zhang He , Li Chao , Lin Guangxing
Published: September 2021

The dust emission parameterization in the Chinese Academy of Sciences Earth System Model version 2 (CAS‐ESM2) is described with emphasis on the implementation process and simulations of global dust cycle and East Asia dust event statistics. The parameterization is based on the scheme of Shao (2004; http://doi.org/10.1029/2003JD004372) which considers two major dust emission mechanisms, namely, saltation bombardment and aggregation disintegration. Shao (2004; http://doi.org/10.1029/2003JD004372) scheme was well tested against field observations and has been widely used in regional dust modeling. Here this scheme is implemented into a global climate model for the first time and thus provides an independent solution for simulating global dust emissions. With this scheme, CAS‐ESM2 reasonably simulates the main dust emission regions in the Earth and reproduces the observations of dust deposition flux and surface dust concentrations at most stations. Compared to the synoptic records of dust events, the model also captures the general patterns and seasonal variations of dust activities in East Asia. However, the model underestimates the frequency of strong dust events (instantaneous surface dust concentrations >1,000 μg m−3) due to the weaker surface winds simulated by the model. The model tends to simulate much weaker and longer‐lasting dust events in Eastern Sources (35–49°N, 94–126.5°E) of northern China, suggesting the weaker and slower‐moving synoptic weather systems associated with dust events in the model. Overall CAS‐ESM2 performs well in simulating the key aspects of global dust distribution and East Asian dust events, yet some biases remain to be improved.
Water Use in the Landscape: A Comparison of Water Quality and Irrigation Technologies on Behavior
Authors: Lee Jonathan M. , Taylor Laura O. , Berglund Emily Z.
Published: September 2021

Reclaimed wastewater for outdoor irrigation purposes is an effective tool for conserving potable water sources and reducing effluent discharge from wastewater treatment facilities. Despite its “green” attributes, we find outdoor watering behavior that is consistent with households treating reclaimed water as a lower quality substitute to potable water for outdoor residential irrigation. Using unique microdata, we estimate the demand for outdoor water and find that after controlling for differences in irrigation water prices, households using reclaim water and households without automatic irrigation systems consume substantially less water in the landscape.
Impacts of Underlying Surface on the Dusty Weather in Central Inner Mongolian Steppe, China
Authors: Bao Chunling , Yong Mei , Bi Lige , Gao Hailin , Li Jun , Bao Yuhai , Gomboludev Purevjav
Published: September 2021

Dust storms are common in northern China and can adversely affect the environment and human health. The Xilingol grassland is the main source of dust storms in China. However, the impacts of different surface features on dusty weather in the Xilingol League remain unclear. This study analyzed the temporal and spatial variation characteristics of surface features and the corresponding effects on dusty weather using data from 13 meteorological stations, MODIS normalized difference vegetation index (NDVI) data, and soil moisture data collected in Xilingol League from 2005 to 2018. Spatially, the dust outbreak frequency (DOF) of Xilingol League decreased gradually from the western desert steppe to the eastern typical steppe. Temporally, the dust outbreak ratio (DOR) and DOF were highest in spring (March–May), with the highest in April. Dusty weather mostly occur in spring but gradually decreased in this season over the 14‐year period. On the contrary, NDVI and soil moisture increased gradually from the west with less precipitation to the east with more precipitation. And showed fluctuating increasing trends over time. The DOR in Xilingol League was negatively correlated with the NDVI and soil moisture, and with the increase of NDVI and soil moisture from the western desert steppe to the eastern typical steppe and the southern cultivated land, the dust emission threshold also increased. The DOR predicted by Xilingol league in spring was significantly correlated with the actual DOR. Our research can provide specific suggestions for different regions of Xilingol League.
Time Evolution of the Surface Urban Heat Island
Authors: Stewart I. D. , Krayenhoff E. S. , Voogt J. A. , Lachapelle J. A. , Allen M. A. , Broadbent A. M.
Published: September 2021

Atmospheric and surface urban heat islands (UHI) originate from common energetic processes, but the status of scientific knowledge on their time evolution is highly disparate. The diurnal cycles of atmospheric UHI are well known based on years of continuous measurements in cities; the cycles of surface UHI, however, cannot be measured continuously or in situ. In this article, we aim to reconcile these differences. We begin with a synthesis of previous work on the diurnal evolution of surface UHI, which leads to a novel but historically minded approach to the research problem. The approach involves a combination of microscale and mesoscale urban climate models, each of which is forced with universally described urban and rural surface parameters and atmospheric profiles. With these models, we produce theoretical time‐temperature curves for the surface UHI that are comparable to the classic curves of atmospheric UHI. This work prompts a critical look at the use of satellite thermal imagery to assess heat islands and heat risks in cities. To that end, we recommend new and more functional definitions of surface temperature. Conceptually, these represent “incomplete” temperatures defined by specific facets of the urban environment.
Modeling Photosynthesis and Exudation in Subtropical Oceans
Authors: Wu Zhen , Dutkiewicz Stephanie , Jahn Oliver , Sher Daniel , White Angelicque , Follows Michael J.
Published: September 2021

Marine phytoplankton contributes nearly half of the total primary production on Earth through photosynthesis. Parameterizations of algal photosynthesis commonly employed in global biogeochemical simulations generally fail to capture the observed vertical structure of primary production. Here we examined the consequences of decoupling photosynthesis (carbon fixation) and biosynthesis (biomass building) with accumulation or exudation of excess photosynthate under energy rich conditions in both regional and global models. The results show that the decoupling of these two processes improved the simulated vertical profile of primary production, increased modeled primary production over 30% globally and over 40% in subtropical oceans, improved simulated meridional patterns of particulate C:N:P and increased modeled surface pool of labile/semi‐labile dissolved organic carbon. More generally, these results highlight the importance of exudation, which results from the decoupling of photosynthesis and biosynthesis, as a major physiological process affecting ocean biogeochemistry.
Covariation of Airborne Biogenic Tracers (CO2, COS, and CO) Supports Stronger Than Expected Growing Season Photosynthetic Uptake in the Southeastern US
Authors: Parazoo Nicholas C. , Bowman Kevin W. , Baier Bianca C. , Liu Junjie , Lee Meemong , Kuai Le , Shiga Yoichi , Baker Ian , Whelan Mary E. , Feng Sha , Krol Maarten , Sweeney Colm , Runkle Benjamin R. , Tajfar Elahe , Davis Kenneth J.
Published: September 2021

The Atmospheric Carbon Transport (ACT)‐America Earth Venture mission conducted five airborne campaigns across four seasons from 2016 to 2019, to study the transport and fluxes of Greenhouse gases across the eastern United States. Unprecedented spatial sampling of atmospheric tracers (CO2, carbon monoxide [CO], carbonyl sulfide [COS]) related to biospheric processes offers opportunities to improve our qualitative and quantitative understanding of seasonal and spatial patterns of biospheric carbon uptake. Here, we examine co‐variation of boundary layer enhancements of CO2, CO, and COS across three diverse regions: the crop‐dominated Midwest, evergreen‐dominated South, and deciduous broadleaf‐dominated Northeast. To understand the biogeochemical processes controlling these tracers, we compare the observed co‐variation to simulated co‐variation resulting from model‐ and satellite‐ constrained surface carbon fluxes. We found indication of a common terrestrial biogenic sink of CO2 and COS and secondary production of CO from biogenic sources in summer throughout the eastern US, driven by stomatal conductance. Upper Midwest crops drive CO2 and COS depletion from early to late summer. Northeastern temperate forests drive CO2 and COS depletion in late summer. The unprecedented ACT‐America flask samples uncovered evidence that southern humid temperate forests photosynthesize and absorb CO2 and COS, and emit CO precursors, deep into the growing season. Satellite‐ constrained carbon fluxes capture much of the observed seasonal and spatial variability, but underestimate the magnitude of net CO2 and COS depletion in the South, indicating a stronger than expected net sink of CO2 in late summer. Additional sampling of the South will more accurately constrain underlying biological processes and climate sensitivities governing southern carbon dynamics.
Isolating Detrital and Diagenetic Signals in Magnetic Susceptibility Records From Methane‐Bearing Marine Sediments
Authors: Johnson Joel E. , Phillips Stephen C. , Clyde William C. , Giosan Liviu , Torres Marta E.
Published: September 2021

Volume‐dependent magnetic susceptibility (κ) is commonly used for paleoenvironmental reconstructions in both terrestrial and marine sedimentary environments where it reflects a mixed signal between primary deposition and secondary diagenesis. In the marine environment, κ is strongly influenced by the abundance of ferrimagnetic minerals regulated by sediment transport processes. Post‐depositional alteration by H2S, however, can dissolve titanomagnetite, releasing reactive Fe that promotes pyritization and subsequently decreases κ. Here, we provide a new approach for isolating the detrital signal in κ and identifying intervals of diagenetic alteration of κ driven by organoclastic sulfate reduction (OSR) and the anaerobic oxidation of methane (AOM) in methane‐bearing marine sediments offshore India. Using the correlation of a heavy mineral proxy from X‐ray fluorescence data (Zr/Rb) and κ in unaltered sediments, we predict the primary detrital κ signal and identify intervals of decreased κ, which correspond to increased total sulfur content. Our approach is a rapid, high‐resolution method that can identify overprinted κ resulting from pyritization of titanomagnetite due to H2S production in marine sediments. In addition, total organic carbon, total sulfur, and authigenic carbonate δ13C measurements indicate that both OSR and AOM can drive the observed κ loss, but AOM drives the greatest decreases in κ. Overall, our approach can enhance paleoenvironmental reconstructions and provide insight into paleo‐positions of the sulfate‐methane transition zone, past enhancements of OSR or paleo‐methane seepage, and the role of detrital iron oxide minerals on the marine sediment sulfur sink, with consequences influencing the development of chemosynthetic biological communities at methane seeps.
Effect of Semidiurnal Lunar Tides Modulated by Quasi‐2‐Day Wave on Equatorial Electrojet During Three Sudden Stratospheric Warming Events
Authors: Li Yaxian , Chen Gang , Zhang Shaodong , Gong Wanlin , Ma Zheng , Huang Kaiming , Gong Yun
Published: September 2021

We present an analysis of perturbations and wave characteristics in equatorial electrojet (EEJ) and equatorial zonal winds in the mesosphere and lower thermosphere region during three sudden stratospheric warming (SSW) events, based on the wind observations by two meteor radars in Indonesia and geomagnetic field observations in India. During three SSWs, remarkable semidiurnal perturbations occurred in the EEJ, accompanied by the strong 2‐day periodic perturbations simultaneously. The semidiurnal lunar (L2) tidal amplitudes in the EEJ and zonal winds showed the prominent enhancements during the episodes of EEJ perturbations. The time‐period power spectra of L2 tidal amplitudes in both the EEJ and zonal winds presented the obvious and coincident quasi‐2‐day wave (QTDW) enhancements during these periods. Our results first reveal the important contribution of QTDW to the distinctive EEJ perturbations during SSWs, and the semidiurnal lunar tides modulated by QTDW serve as the main forcing agent therein.
Reanalysis of the Ionospheric Total Electron Content Anomalies Around the 2011 Tohoku‐Oki and 2016 Kumamoto Earthquakes: Lack of a Clear Precursor of Large Earthquakes
Authors: Ikuta Ryoya , Oba Ryoto , Kiguchi Daiki , Hisada Tomoya
Published: September 2021

We investigate the veracity of the reports by Iwata and Umeno (2016, https://doi.org/10.1002/2016ja023036) and Iwata and Umeno (2017, https://doi.org/10.1002/2017ja023921), both of which claimed that the observed perturbations in Global Navigation Satellite System (GNSS)‐based ionospheric total electron content (TEC) could serve as a "precursor" of large earthquakes based on correlation analysis. Iwata and Umeno (2016, https://doi.org/10.1002/2016ja023036) defined a spatial correlation of residuals between the observed and predicted TEC time series. They reported that the correlation value is significantly larger before large earthquakes than those observed during non‐earthquake periods. Iwata and Umeno (2017, https://doi.org/10.1002/2017ja023921), who applied the same method to other large earthquake, claimed that the preseismic ionospheric disturbances can be distinguished from other non‐earthquake phenomena based on the small percentage of area where the correlation value exceeds the criterion. They also claimed that the low propagation velocity of the correlation peaks is also a preseismic characteristic. Here we tested their claims using a larger data set. As a result, these three characteristics they claimed to have captured as evidence of earthquake precursors are not significant being frequently observed during normal (nonearthquake) days. In addition to that, the criteria of Iwata and Umeno (2017, https://doi.org/10.1002/2017ja023921) cannot be applied to the large earthquake discussed by Iwata and Umeno (2016, https://doi.org/10.1002/2016ja023036), and vice versa. Therefore, we can find no basis for claiming that they detected precursors to the earthquakes. The calculation procedure of the correlation function shows that the value is more of an indicator that amplifies small variations synchronized between nearby stations, like medium‐scale traveling ionospheric disturbances rather than earthquake precursors.
Latitudinal Beaming of Jupiter's Radio Emissions From Juno/Waves Flux Density Measurements
Authors: Louis C. K. , Zarka P. , Dabidin K. , Lampson P.‐A. , Magalhães F. P. , Boudouma A. , Marques M. S. , Cecconi B.
Published: September 2021

The observations from the Juno spacecraft in polar orbit of Jupiter provide for the first time a complete view of Jupiter's radio emissions from all latitudes. Characterizing the latitudinal distribution of radio emissions' occurrence and intensity is a useful step for elucidating their origin. Here, we analyze for that purpose the first 3 years of observations from the Waves experiment on the Juno spacecraft (mid‐2016 to mid‐2019). Two prerequisites for the construction of the latitudinal distribution of intensities for each Jovian radio component are (a) to work with absolute flux densities and (b) to be able to associate each radio measurement with a specific radio component. Accordingly, we develop a method to convert the Juno/Waves data in flux densities and then we build a catalog of all Jovian radio components over the first 3 years of Juno's orbital mission. From these, we derive occurrence and intensity distributions versus observer's latitude and frequency for each component; these will be the basis for future detailed studies and interpretations of each component's characteristics and origin.
On the Solar Wind Proton Temperature Anisotropy at Mars' Orbital Location
Authors: Lentz C. L. , Chasapis A. , Qudsi R. A. , Halekas J. , Maruca B. A. , Andersson L. , Baker D. N.
Published: September 2021

The Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft can act as an intermittent upstream solar wind monitor at 1.5 AU. To inspect the evolution of solar wind turbulence in the Martian exosphere, we have gathered proton (i.e., ionized hydrogen) temperature measurements taken by the Solar Wind Ion Analyzer (SWIA) onboard the MAVEN spacecraft. Here we investigate instabilities driven by the proton temperature anisotropy at Mars during southern hemisphere fall, winter, spring, and summer seasons. We look at the relationship between the temperature anisotropy, (i.e., the ratio of the perpendicular proton temperature component to the parallel proton temperature component), and the parallel plasma beta, , to determine any constraints imposed by kinetic instabilities. Furthermore, we report on the properties of turbulence near Mars' orbital location during upstream solar wind intervals from January 2015 to December 2016 (1 Martian year). We find that the probability distributions of ()‐values become limited when deviates greatly from unity. We also find evidence of intermittency implying nonlinear, non‐homogeneous energy transfer. Additionally, spectral indices obtained from basic fittings of power spectral densities of magnetic field fluctuations demonstrate a power law decay for inertial ranges ( Hz to 0.1 Hz).
Hydrostatic Dehydration Fabrics of Antigorite at High Pressure and High Temperature: Implications for Trench Parallel Seismic Anisotropy at Convergent Plate Boundaries
Authors: Liu W. L. , Qi H. W. , Zhang J. F. , Wu X. , Li J. F. , Zhao R. , Wang Y. F. , Jin Z. M.
Published: September 2021

Antigorite dehydration is well known as a key process at convergent boundaries for the genesis of mantle wedge partial melting and intermediate‐depth earthquakes. However, the crystallographic preferred orientations (CPOs) of prograde minerals from antigorite dehydration and their effects on the seismic anisotropy of subducting slabs remain ambiguous and controversial. Here we report antigorite dehydration experiments on a foliated serpentinized peridotite at pressures of 0.3–6 GPa and temperatures of 700–900°C. Our results show that olivine CPO evolves from a fiber‐[100] type in fine grains to a type‐C like in coarse grains. We propose that the fiber‐[100] olivine CPO is developed by topotactic growth during incipient hydrostatic dehydration, while the orthorhombic type‐C like olivine CPO is developed by anisotropic growth resulting from an anisotropic fluid flow during later dehydration. The type‐C like olivine CPO in the antigorite‐rich layers after antigorite dehydration could contribute to the trench parallel fast shear wave seismic anisotropy at convergent plate boundaries.
Rock Deformation Monitoring Using Monte Carlo Waveform Inversion
Authors: Lai Ssu‐Ting , Fuji Nobuaki , Katayama Ikuo , Bonilla Luis Fabian , Capdeville Yann
Published: September 2021

We estimate elastic and anelastic parameters and their evolution during laboratory rock deformation experiments, while developing a Monte Carlo waveform inversion. The transducer‐to‐transducer one‐source one‐station active seismic data of dry and water‐saturated samples are obtained from Zaima and Katayama (2018), https://doi.org/10.1029/2018JB016377. We first performed a trial‐and‐error estimate of the boundary conditions in order to suppress its influence on waveforms. The synthetic seismic data were generated using equivalent homogeneous models with different combinations of elastic and anelastic parameters with the aid of spectral element method. We compared them with the laboratory experimental data. Based on the comparisons, we obtained the time‐lapse variations of seismic velocities and attenuation of rock samples during deformation experiments, which we interpreted as crack developments. Our simultaneous estimation of elastic and anelastic parameters allowed us to detail the dynamics prior to the rock failure.
A Newly Discovered Late‐Cretaceous East Asian Flat Slab Explains Its Unique Lithospheric Structure and Tectonics
Authors: Peng Diandian , Liu Lijun , Wang Yaoyi
Published: September 2021

The existence of historical flat slabs remains debated. We evaluate past subduction since 200 Ma using global models with data assimilation. By reproducing major Mesozoic slabs whose dip angles satisfy geological constraints, the model suggests a previously unrecognized continental‐scale flat slab during the Late Cretaceous beneath East Asia, a result independent of plate reconstructions, continental lithospheric thickness, convergence rate, and seafloor age. Tests show that the pre‐Cretaceous subduction history, both along the western Pacific and Tethyan trenches, is the most important reason for the formation of this prominent flat Izanagi slab. Physically, continuing subduction increases the gravitational torque, which, through balancing the suction torque, progressively reduces dynamic pressure above the slab and decreases the slab dip angle. The flat Izanagi slab explains the observed East Asian lithospheric thinning that led to the formation of the North‐South Gravity Lineament, tectonic inversion of sedimentary basins, uplift of the Greater Xing'an‐Taihang‐Xuefeng mountains and the abrupt termination of intraplate volcanism during the Late Cretaceous.