bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of predictive optimization model for autonomous rotary drilling system using machine learning approach
Authors: Amadi Kingsley , Iyalla Ibiye , Prabhu Radhakrishna , Alsaba Mortadha , Waly Marwa
Published: June 2023

The growing global energy demand and strict environmental policies motivate the use of technology and performance improvement techniques in drilling operations. In the traditional drilling method, the effort and time required to optimize drilling depend on the effectiveness of human driller in selecting the optimal set of parameters to improve system performance. Although existing work has identified the significance of upscaling from manual drilling to autonomous drilling system, little has been done to support this transition. In this paper, predictive optimization model is proposed for autonomous drilling systems. To evaluate optimized operating procedure, a comparative study of surface operating parameters using weight on bit (WOB), rotary speed (RPM) versus drilling mechanical specific energy (DMSE), and feed thrust (FET) is presented. The study used a data-driven approach that uses offset drilling data with machine learning model in finding a pair of input operating variables that serves as best tuning parameters for the topdrive and drawwork system. The results illustrate that derived variables (DMSE, FET) gave higher prediction accuracy with correlation coefficient (R2) of 0.985, root mean square error (RMSE) of 7.6 and average absolute percentage error (AAPE) of 34, whilst using the surface operating parameters (WOB, RPM) delivered an R2, RMSE and AAPE of 0.74, 28 and 106, respectively. Although previous researches have predicted ROP using ANN, this research considered the selection of tuning control variables and using it in predicting the system ROP for an autonomous system. The model output offers parameter optimization and adaptative control of autonomous drilling system.
Paleoclimate quantitative reconstruction and characteristics of continental red beds: a case study of the lower fourth sub-member of Shahejie Formation in the Bonan Sag
Authors: Xu Qisong , Wang Yongshi , Ma Lichi , Yue Yu , Meng Tao , Bi Junfeng , Jiang Chao
Published: June 2023

Varied origins have the ability to construct the continental red beds, such as paleoclimate, provenance, drainage status, etc. Reconstructing paleoclimate is the key to investigate the origin. Thus, this paper outlines the normal distribution constrained method (NDCM) to reconstruct paleoclimate quantitatively and accurately during the lower fourth sub-member of Shahejie (Es4x) in the Bonan Sag, which is in low requirement of data and environmental conditions. Based on the NDCM, the paleoclimate is still in a long-term arid background as the potential evapotranspiration rates (PERs) are larger than 6 in the transgressive system tract (TST) and regressive system tract (RST) during the period of Es4x. The decreasing PERs that range from 6.28 to 6.04, decreasing atmospheric temperature range from 14.37 to 13.95 °C and increasing mean precipitation of the wettest month and mean precipitation of the driest month indicate the paleoclimate is breaking away from the hot and arid background from TST to RST. Meanwhile, the paleoclimate fluctuation develops decreasing frequency and increasing amplitude which can be inferred from the increasing standard deviation (std), Th/K and Th/U curves. The hot and arid background is still the main origin of red color during the Es4x. Moreover, the other origin may also develop since there is no clear law between red coloration and the developing location of sediments.
A note on groups with a large permodularly embedded subgroup
Authors: De Falco Maria , de Giovanni Francesco , Musella Carmela
Published: June 2023

It is known that if G is a group such that the centre factor group
$$G/\zeta (G)$$

G
/
ζ
(
G
)

is polycyclic, then also the commutator subgroup
$$G'$$

G
′

is polycyclic. The aim of this paper is to describe this situation from a lattice point of view. It is proved that if G is a group admitting a permodularly embedded non-periodic subgroup P such that the interval [G/P] is a polycyclic lattice, then G contains a polycyclic normal subgroup N such that G/N is quasihamiltonian.
The multifaceted nature of cooperation for innovation, ICT and innovative outcomes: evidence from UK Microdata
Authors: Giovannetti Emanuele , Piga Claudio
Published: June 2023

Cooperation in innovation activities is a key building block in forming entrepreneurial innovation networks. However, the impact on innovation of different forms of cooperation among multiple stakeholders composing a firm’s relational environment can be dramatically different, depending on whether the modalities of cooperation are tacit or explicit and the type of functional relations between the cooperating organizations. Information and Communication Technologies (ICTs) facilitate cooperation and innovation outcomes. The main aim of this paper is to disentangle the effects of explicit vs. tacit and complementarity vs. competitive modalities of cooperation in innovation activities on innovation outputs. Based on pooled UK Microdata from 2004 to 2010, this paper’s main finding is that tacit cooperation, emerging from R&D and ICTs spillovers, increases firms’ likelihood to introduce process, product, and organizational innovations. We also find that a firm’s functional relation with its cooperating peers determines the sign of the association with innovation outcomes: explicit cooperation among competitors lowers the level of innovations. In contrast, cooperation along the value chain brings more innovations.
Modelling of fatigue damage in granitic rock by piezoelectric effect in quartz phase due to alternating current excitation
Authors: Saksala Timo , Ruiz Arturo Rubio , Kouhia Reijo , Kane Alexandre , Hokka Mikko
Published: June 2023

This paper considers numerical modelling of hypothetical fatigue damage in granitic rock by alternating current (AC) excitation of piezoelectric properties of Quartz. For this end, a numerical method consisting of a rock mineral mesostructure model, an implicit time stepping scheme to solve the piezoelectro-mechanical problem, and a fatigue damage model was developed. The rock material was assumed to be heterogenous linear elastic and isotropic, save the Quartz piezoelectric properties, which are anisotropic. An evolution equation-based continuum scalar damage model based on an evolving back stress tensor and a moving Drucker–Prager type of endurance surface was applied to compute the damage inflicted by the AC excitation. The damage was computed in a post-processed mode, i.e., un-coupled to the material model, at this stage of investigations. Some preliminary axisymmetric simulations are presented with a rock mesotructure based on electron backscatter diffraction data. These simulations corroborate the hypothesis that fatigue damage can be induced on granitic rock by converse piezoelectric effect in the Quartz phase by sinusoidal alternating current. More specifically, fatigue damage was induced on a disc-shaped numerical rock sample at a voltage of 15 kV with 2.5 kHz of frequency.
An application of a supervised machine learning model for predicting life expectancy
Authors: Lipesa Brian Aholi , Okango Elphas , Omolo Bernard Oguna , Omondi Evans Otieno
Published: June 2023

The social and financial systems of many nations throughout the world are significantly impacted by life expectancy (LE) models. Numerous studies have pointed out the crucial effects that life expectancy projections will have on societal issues and the administration of the global healthcare system. The computation of life expectancy has primarily entailed building an ordinary life table. However, the life table is limited by its long duration, the assumption of homogeneity of cohorts and censoring. As a result, a robust and more accurate approach is inevitable. In this study, a supervised machine learning model for estimating life expectancy rates is developed. The model takes into consideration health, socioeconomic, and behavioral characteristics by using the eXtreme Gradient Boosting (XGBoost) algorithm to data from 193 UN member states. The effectiveness of the model’s prediction is compared to that of the Random Forest (RF) and Artificial Neural Network (ANN) regressors utilized in earlier research. XGBoost attains an MAE and an RMSE of 1.554 and 2.402, respectively outperforming the RF and ANN models that achieved MAE and RMSE values of 7.938 and 11.304, and 3.86 and 5.002, respectively. The overall results of this study support XGBoost as a reliable and efficient model for estimating life expectancy.
Im Namen des Volkes? Neue Sichtweisen auf die polnische Geschichte
Authors: Saryusz-Wolska Magdalena
Published: June 2023

Die Besprechung präsentiert jüngste polnische Publikationen, die sich der „Geschichte des polnischen Volkes“, das heißt hauptsächlich der Geschichte der polnischen Bäuerinnen und Bauern sowie der Arbeiterinnen und Arbeiter, widmen. Allein zwischen 2020 und 2022 sind fünf solche Bücher in großen Auflagen erschienen. Ihre Autoren – Adam Leszczyński, Kacper Pobłocki, Kamil Janicki, Michał Rauszer und Mateusz Wyżga – initiierten hitzige Debatten über die soziale Herkunft der heutigen polnischen Gesellschaft sowie über die (mangelnde) Interdisziplinarität der bisherigen Geschichtswissenschaften in Polen. Die Autorin des Essays zeigt auf, dass es bereits vor dem Erscheinen der jüngsten Publikationen Anzeichen einer Neuorientierung im Bereich der Geschichtswissenschaften gab. Allerdings hielten erst die diskutierten fünf Bücher Einzug in die Öffentlichkeit jenseits der Fachkreise. Dieses öffentliche Interesse sei, so argumentiert die Autorin, Ausdruck von gegenwärtigen Wandlungen der Erinnerungskultur in Polen. Der bisherig dominierende Fokus auf die ‚Nation‘ stellt sich angesichts der Einwanderung, vor allem aus den weiter östlich liegenden Ländern, als unzureichend heraus. Die Verlegung des erinnerungskulturellen Schwerpunkts von der ‚Nation‘ auf die ‚Klasse‘ hat hingegen ein integratives Potenzial.
Physiological Changes and Nutritional Value of Forage Clitoria Grown in Arid Agro-Ecosystem as Influenced by Plant Density and Water Deficit
Authors: Shaaban Ahmed , Mahfouz Hamdy , Megawer Ekram Ali , Saudy Hani Saber
Published: June 2023

Forage crop productivity has lately reduced in countries located in arid and semi-arid regions worldwide due to intensive consumption and the successive years of drought. This problem is exacerbated by the progress of water scarcity. Thus, the current study is aimed at improving the forage productivity and quality of clitoria as a leguminous fodder crop to be involved in crop rotations under low water supply conditions. As an attempt for facing the drought issue, a two-year (SI and SII) field experiment was conducted to evaluate the influence of irrigation pattern (IP) and plant density (PD) on clitoria morpho-physiological attributes, nutritive value, productivity, and irrigation water-use efficiency (IWUE) in two growth cycles (GCI and GCII). Based on the soil water depletion method, three irrigation patterns of 100% (IP0%, full irrigation), 80% (IP20%), and 60% (IP40%) were applied. The tested plant densities were 33 (PD33), 22 (PD22), and 17 (PD17) plants m−2. Findings revealed that IP0%× PD22was the efficient treatment for enhancing the physio-biochemical attributes. However, in SI IP0%× PD22statistically at par (p≥0.05) with IP0%× PD33, IP20%× PD22, and IP20%× PD17(for chlorophyll content in GCI); IP0%× PD17and IP20%× PD22(for leaf relative water content in GCII); and IP0%× PD33, IP20%× PD33, and IP20%× PD22(for cell membrane stability index in GCII). Along the two seasons, IP40%× PD33was the potent practice for producing the highest leaf: stem ratio in both GCI (2.07 and 1.78) and GCII (1.18 and 0.96). Under IP40%, PD33treatment recorded the greatest protein content in both GCI (24.1–27.0%) and GCII (21.7–19.5%) of SI and SII equaling PD22in GCII (21.2–18.9%) of both seasons and PD17in both GCI (24.0%) and GCII (21.5%) of SI and GCII (19.3%) of SII. The best aggregate protein yield for SI and SII was obtained under IP20%× PD33interaction (1.36 and 1.40 t ha−1) without significant difference (p≥0.05) with IP0%× PD33or IP40%× PD33interactions. The greatest aggregate dry forage yield was observed in SI under IP0%or IP20%combined with PD33(7.77 and 7.52 t ha−1) which did not differ significantly (p≥0.05). It could be concluded that irrigation by 80% water of full irrigation was found to be an efficient water-saving tactic coupled with adjusting the plant density of 33 plants m−2, which improved clitoria forage quantitative and qualitative properties, in addition to enhancing IWUE. Since leaf relative water content and cell membrane stability index decreased and proline increased in plant tissues under deficit water, clitoria is plant considered a moderately drought tolerant. Thus, clitoria is a promising plant could be successfully grown under arid agro-ecosystems.
Allergic and other adverse reactions to drugs used in anesthesia and surgery
Authors: Baldo Brian A.
Published: June 2023

The list of drugs patients may be exposed to during the perioperative and postoperative periods is potentially extensive. It includes induction agents, neuromuscular blocking drugs (NMBDs), opioids, antibiotics, sugammadex, colloids, local anesthetics, polypeptides, antifibrinolytic agents, heparin and related anticoagulants, blue dyes, chlorhexidine, and a range of other agents depending on several factors related to individual patients’ clinical condition and progress in the postoperative recovery period. To avoid poor or ultrarapid metabolizers to a particular drug (for example tramadol and codeine) or possible adverse drug reactions (ADRs), some drugs may need to be avoided during or after surgery. This will be the case for patients with a history of anaphylaxis or other adverse events/intolerances to a known drug. Other drugs may be ceased for a period before surgery, e.g., anticoagulants that increase the chance of bleeding; diuretics for patients with acute renal failure; antihypertensives relative to kidney injury after major vascular surgery; and serotonergic drugs that together with some opioids may rarely induce serotonin toxicity. Studies of germline variations shown by genotyping and phenotyping to identify a predisposition of genetic factors to ADRs offer an increasingly important approach to individualize drug therapy. Studies of associations of human leukocyte antigen (HLA) genes with some serious delayed immune-mediated reactions are ongoing and variations of drug-metabolizing cytochrome CYP450 enzymes, P-glycoprotein, and catechol-O-methyltransferase show promise for the assessment of ADRs and non-responses to drugs, particularly opioids and other analgesics. Surveys of ADRs from an increasing number of institutions often cover small numbers of patients, are retrospective in nature, fail to clearly identify culprit drugs, and do not adequately distinguish immune-mediated from non-immune-mediated anaphylactoid reactions. From the many surveys undertaken, the large list of agents identified during and after anesthesia and surgery are examined for their ADR involvement. Drugs are classified into those most often involved, (NMBD and antibiotics); drugs that are becoming more frequently implicated, namely antibiotics (particularly teicoplanin), and blue dyes; those becoming less frequently involved; and drugs more rarely involved in perioperative, and postoperative adverse reactions but still important and necessary to keep in mind for the occasional potential sensitive patient. Clinicians should be aware of the similarities between drug-induced true allergic type I IgE/FcεRI- and pseudoallergic MRGPRX2-mediated ADRs, the clinical features of each, and their distinguishing characteristics. Procedures for identifying MRGPRX2 agonists and diagnosing and distinguishing pseudoallergic from allergic reaction mechanisms are discussed.

Graphical Abstract
Locusts of Power
Authors: Dolbee Samuel
Published: June 2023

In this highly original environmental history, Samuel Dolbee sheds new light on borders and state formation by following locusts and revealing how they shaped both the environment and people's imaginations from the late Ottoman Empire to the Second World War. Drawing on a wide range of archival research in multiple languages, Dolbee details environmental, political, and spatial transformations in the region's history by tracing the movements of locusts and their intimate relationship to people in motion, including Arab and Kurdish nomads, Armenian deportees, and Assyrian refugees, as well as states of the region. With locusts and moving people at center stage, surprising continuities and ruptures appear in the Jazira, the borderlands of today's Iraq, Syria, and Turkey. Transcending approaches focused on the collapse of the Ottoman Empire or the creation of nation states, Dolbee provides a new perspective on the modern Middle East grounded in environmental change, state violence, and popular resistance.
Don't Forget about Me
Authors: Fligg David
Published: June 2023

Gideon Klein was one of the most gifted musicians of his generation. This book traces his short life through his music, his diaries and documents as well as the reminiscences of his friends and family.
The war in Ukraine: Consequences for the economy, labour class and equitable development in Europe and beyond
Authors: Żuk Piotr
Published: June 2023

This article encourages critical discussion about the economic and social consequences of the war in Ukraine. This war has global effects in various dimensions of social life: energy policy, the environmental dimension, the economic sphere, and also the political atmosphere. In each of these dimensions, it poses a threat to sustainable development and the interests of the labour class in Europe. It attempts to change the balance of power in global geopolitics and also proves to be a useful cover for attempts to change the model of relations between employees and the state and business in many European countries. Due to the conflict in Ukraine and the ensuing calls for increased efforts to ‘ensure security’, Europe has turned towards a war economy in which the interests of the arms industry are more important than the interests of the working classes. The war in Ukraine has proved to be an excellent justification for governments to lower social standards and get rid of the remnants of the welfare state. From this perspective, the atmosphere of the New Cold War becomes a challenge for the labour movement, the global left and all progressive social circles.
Do Politicians Outside the United States Also Think Voters Are More Conservative than They Really Are?
Authors: PILET JEAN-BENOIT , SHEFFER LIOR , HELFER LUZIA , VARONE FREDERIC , VLIEGENTHART RENS , WALGRAVE STEFAAN
Published: June 2023

In an influential recent study, Broockman and Skovron (2018) found that American politicians consistently overestimate the conservativeness of their constituents on a host of issues. Whether this conservative bias in politicians’ perceptions of public opinion is a uniquely American phenomenon is an open question with broad implications for the quality and nature of democratic representation. We investigate it in four democracies: Belgium, Canada, Germany, and Switzerland. Despite these countries having political systems that differ greatly, we document a strong and persistent conservative bias held by a majority of the 866 representatives interviewed. Our findings highlight the conservative bias in elites’ perception of public opinion as a widespread regularity and point toward a pressing need for further research on its sources and impacts.
TERTULLIAN'S CHRISTIAN CHAMELEON
Authors: Woods David
Published: June 2023

It is argued that Tertullian's relatively lengthy description of a chameleon in his De pallio serves as a metaphor not so much for the convert to a philosophical way of life in general but for the convert to Christianity in particular. The argument rests on the unusual emphases within this description which recall different features of Christianity or popular beliefs about the same.
Myringotomy tube placement: understanding the impact of the coronavirus disease 2019 pandemic
Authors: Uppal Priya A , Jayapal Aishwarrya , Jetjomlong Tyler , Merchant Rida , Khatiashvili Ana , Moritz Ethan , Feustel Paul J , Reichert Lara
Published: June 2023

Objective

Otolaryngologists perform bilateral myringotomy and tube placement for surgical management for otitis media with effusion. This retrospective study aimed to address the extent to which the coronavirus disease 2019 pandemic and season impact the number of bilateral myringotomy and tube placement procedures performed at a tertiary care centre.

Methods

A total of 1248 charts of children who underwent bilateral myringotomy and tube placement from January 2018 through February 2021 were reviewed.

Results

The cohort included 41.6 per cent females and 58.4 per cent males, with 63.7 per cent having private insurance. The median age at surgery was 2.6 years. The spring season had the most bilateral myringotomy and tube placement procedures per week. The number of bilateral myringotomy and tube placement procedures performed per week after the onset of the coronavirus disease 2019 pandemic was significantly lower compared to the years prior. There was no difference in number of intra-operative effusions pre-pandemic versus after the pandemic onset.

Conclusion

This study sheds light on the impact of the coronavirus disease 2019 pandemic and seasonality on the rates of tympanostomy tube procedures, vital for understanding the temporality of ear infections.
‘Brainwork practices’: responsibilisation of dementia prevention in Australian aged care discourse
Authors: Chelberg Kristina
Published: June 2023

Successful ageing continues to be a key theme in contemporary ageing discourses, where good physical and cognitive health in older age is an individualised responsibility. This paper explores how Australian aged care stakeholder discourse contributes to constructions of self-responsibility for brain health and dementia prevention in older persons. Brain health advice messages about diet, exercise and ‘brain fitness’ by aged care stakeholders are argued to construct a moral framework of ‘brainwork practices’ to prevent or delay dementia. This study performed discourse analysis of a sample of public online aged care stakeholder documents (N = 170) to reveal three key concepts in discursive constructions of dementia. The first concept characterises dementia as a disastrous force to be opposed; the second is a biomedical concept of dementia as preventable (or able to be delayed) in a ‘successful’ older age, while the third reflects neurocultural ideas that fetishise perfect memory as the best defence against cognitive decline and dementia. Identifying this matrix of responsibilising ‘brainwork practices’ messages by aged care stakeholders makes a contribution within social gerontology to revealing neoliberal conceptions of older age as an outcome of lifestyle and consumer choices, where dementia is constructed as ‘failed’ or ‘unsuccessful’ ageing.
Precision Medicine and Rough Justice: Wicked Problems
Authors: Fleck Leonard M.
Published: June 2023

What exactly is a “wicked problem”? It is a social or economic problem that is so complex and so interconnected with other issues that it is extraordinarily difficult or impossible to resolve. This is because all proposed resolutions generate equally complex, equally wicked problems. In this essay, I argue that precision medicine, especially in the context of the U.S. healthcare system, generates numerous wicked problems related to distributive justice. Further, I argue that there are no easy solutions to these wicked problems. The need for trade-offs is inescapable. Rough justice is the best outcome we can hope for, and that outcome requires a commitment to processes of public reason that are fair and inclusive.
The usage of there sentences with become: the relationship between change of state and appearance/occurrence
Authors: MINO TAKASHI
Published: June 2023

Numerous studies have investigated the kinds of verbs that can be used with there constructions. Generally, only existence and appearance verbs can occur in there constructions. However, some cases have been observed involving verbs not lexically expressing existence or appearance. This study focuses on there sentences with the verb become which are noteworthy in the following two respects. First, although the verb become is not an existence or appearance verb but a change-of-state verb, the verb is felicitously used with there constructions. Second, become is used without an adjectival or nominal complement, a unique argument realization pattern of the verb not found in other syntactic contexts. This study, based on a detailed examination of actual data in corpora, claims that there sentences with become express the appearance/occurrence of an entity. Although the postverbal noun is structurally a subject in there constructions and the subject of the verb become is usually interpreted as an entity undergoing a change, the postverbal noun of there sentences with become is an entity that has arisen as a result of the changing event.
Neuroblastoma survivors’ self-reported late effects, quality of life, health-care use, and risk perceptions
Authors: Tan Jessica , McLoone Jordana K. , Wakefield Claire E. , Nassar Natasha , Cohn Richard J. , Signorelli Christina
Published: June 2023

Background

Survivors of childhood neuroblastoma are at risk of multiple treatment-related health problems (late effects), impacting their quality of life. While late effects and quality of life among Australia and New Zealand (ANZ) childhood cancer survivors have been reported, the outcomes of neuroblastoma survivors specifically have not been reported, limiting critical information to inform treatment and care.

Methods

Young neuroblastoma survivors or their parents (as proxy for survivors <16 years) were invited to complete a survey and optional telephone interview. Survivors’ late effects, risk perceptions, health-care use, and health-related quality of life were surveyed and analyzed using descriptive statistics and linear regression analyses. In-depth interviews explored participants’ experiences, knowledge, and perception of late effects and information needs. Thematic content analysis was used to summarize the data.

Results

Thirty-nine neuroblastoma survivors or parents completed questionnaires (median age = 16 years, 39% male), with 13 also completing interviews. Thirty-two participants (82%) reported experiencing at least 1 late effect, most commonly dental problems (56%), vision/hearing problems (47%), and fatigue (44%). Participants reported high overall quality of life (index = 0.9, range = 0.2–1.0); however, more participants experienced anxiety/depression compared to the population norm (50% met criteria versus 25%, χ2 = 13, p < 0.001). Approximately half of participants (53%) believed they were at risk of developing further late effects. Qualitatively, participants reported knowledge gaps in understanding their risk of developing late effects.

Conclusion

Many neuroblastoma survivors appear to experience late effects, anxiety/depression and have unmet cancer-related information needs. This study highlights important areas for intervention to reduce the impact of neuroblastoma and its treatment in childhood and young adulthood.
Institutions and tax capacity in sub-Saharan Africa
Authors: Tagem Abrams Mbu Enow , Morrissey Oliver
Published: June 2023

This paper contributes to research on the institutional determinants of tax capacity using annual data from 39 sub-Saharan African countries from 1985 to 2018 to construct a measure of tax capacity for each country based on the trend component of the ratio of actual to potential tax revenue. Potential revenue is estimated by a parsimonious tax performance specification, including only variables found to be robust determinants of the tax/GDP ratio. The results show that, on average, tax capacity is high (given potential) and has improved over time (especially for low-income countries). The final stage of analysis selects, from a wide variety of economic and institutional variables, the most important determinants of cross-country variation in tax capacity. Equal distribution of resources is the most important institutional factor associated with greater capacity, consistent with perceptions of equity supporting the fiscal bargain; corruption is associated with lower capacity, consistent with undermining trust in government. Private consumption and resource rents are associated with greater capacity. Other institutional factors are indirectly associated with greater capacity, such as accountability and elements of democracy associated with equity in the allocation and use of public resources.
Estimation of the Nucleation Location and Rupture Extent of the 1850 Xichang, Sichuan, China, Earthquake by Dynamic Rupture Simulations on a Multi‐Segment Stepover Structure
Authors: Yu Houyun , Zhang Zhenguo , Hu Feng , Xu Duyuan , Chen Xiaofei
Published: June 2023

We simulated the rupture dynamics and ground motion of the 1850 Xichang, China, earthquake on the Zemuhe fault, which consists of the Lijinbao segment, the Dajing segment, the Chechejie segment, and the Songxin segment, with the curved grid finite‐difference method, and compared the simulation results with the field observed data and written records inferred data. We focused on the rupture extent of this earthquake and the effects of the maximum principal stress azimuth and nucleation location on the rupture process and the corresponding damage distribution. Numerical simulation results suggest that the regional maximum principal stress orientation that surrounds the Zemuhe fault was approximately N55°W, which is identical with the azimuth from the stress relief experiment in the neighboring area. Our simulations further imply that the nucleation location is under Lanbiluo. The simulation of this preferred nucleation location model suggests that the rupture propagated through the entire Dajing segment and the Chechejie segment, and the rupture gradually arrested at shallow depths after it transferred to the Lijinbao segment and the Songxin segment. Moreover, the simulation suggests that the rupture on the Chechejie segment was initiated at the surface and then mainly propagated downward due to the free surface effect. In addition, the Xichang earthquake may have exhibited a low rupture velocity on the Dajing segment. Furthermore, our simulation results emphasize the importance of the stepover width in the earthquake dynamics.
Prescribed Burns as a Tool to Mitigate Future Wildfire Smoke Exposure: Lessons for States and Rural Environmental Justice Communities
Authors: Kelp Makoto M. , Carroll Matthew C. , Liu Tianjia , Yantosca Robert M. , Hockenberry Heath E. , Mickley Loretta J.
Published: June 2023

Smoke from wildfires presents one of the greatest threats to air quality, public health, and ecosystems in the United States, especially in the West. Here we quantify the efficacy of prescribed burning as an intervention for mitigating smoke exposure downwind of wildfires across the West during the 2018 and 2020 fire seasons. Using the adjoint of the GEOS‐Chem chemical transport model, we calculate the sensitivities of population‐weighted smoke concentrations in receptor regions, including states and rural environmental justice communities, to fire emissions upwind of the receptors. We find that the population‐weighted smoke exposure across the West during the September 2020 fires was 44 μg/m3 but would have been 20%–30% greater had these wildfires occurred in October or November. We further simulate a set of prescribed burn scenarios and find that controlled burning interventions in northern California and the Pacific Northwest could have reduced the population‐weighted smoke exposure across the western United States by 21 μg/m3 in September 2020, while doing so in all other states would have reduced smoke exposure by only 1.5 μg/m3. Satellite records of large, prescribed burns (>1,000 acres, or 4 km2) reveal that northern California and western Oregon conducted only seven such prescribed fires over a 6‐year period (2015–2020), even though these regions have a disproportionate impact on smoke exposure for rural environmental justice communities and population centers across the West. Our analysis suggests that prioritizing northern California and the Pacific Northwest for prescribed burns might mitigate future smoke exposure.
Internal Gravity Waves Generated by Subglacial Discharge: Implications for Tidewater Glacier Melt
Authors: Cusack J. M. , Jackson R. H. , Nash J. D. , Skyllingstad E. , Pettit E. C. , Sutherland D. A. , Motyka R. J. , Amundson J. M.
Published: June 2023

Submarine melting has been implicated in the accelerated retreat of marine‐terminating glaciers globally. Energetic ocean flows, such as subglacial discharge plumes, are known to enhance submarine melting in their immediate vicinity. Using observations and a large eddy simulation, we demonstrate that discharge plumes emit high‐frequency internal gravity waves that propagate along glacier termini and transfer energy to distant regions of the terminus. Our analysis of wave characteristics and their correlation with subglacial discharge forcing suggest that they derive their energy from turbulent motions within the discharge plume and its surface outflow. Accounting for the near‐terminus velocities associated with these waves increases predicted melt rates by up to 70%. This may help to explain known discrepancies between observed melt rates and theoretical predictions. Because the dynamical ingredients—a buoyant plume rising through a stratified ocean—are common to many tidewater glacier systems, such internal waves are likely to be widespread.
Cross‐Property Relationship Between Electrical Resistivity and Elastic Wave Velocity of Crustal Rocks From the Oman Drilling Project Hole GT3A: Implications for in Situ Geophysical Properties of Oceanic Crust
Authors: Akamatsu Y. , Nagase K. , Abe N. , Okazaki K. , Hatakeyama K. , Katayama I.
Published: June 2023

Geophysical properties of oceanic crust are strongly influenced by the presence of cracks. We studied the effects of cracks on the physical properties of oceanic crustal rocks collected from the ICDP Oman Drilling Project Hole GT3A. Electrical resistivity and P‐ and S‐wave velocities were measured under dry and brine‐water‐saturated conditions for each sample. The experimental results reveal that electrical resistivity and elastic wave velocities are differently correlated with porosity. We performed joint inversion of the measured electrical and elastic properties combining an effective medium model by Kachanov and a statistical crack fluid flow model by Guéguen and Dienes with percolation theory. As a result, the variations in electrical and elastic properties can be related to the crack microstructural parameters: crack density and aspect ratio, as well as connectivity of cracks evaluated from crack density. To understand the influence of in situ conditions of oceanic crust, the joint inversion using the proposed cross‐property relationship was performed for geophysical properties obtained by logging measurements at IODP Hole 1256D. Results show the depth variations of resistivity and sonic velocities can be successfully interpreted by decreasing crack porosity and connectivity. Our data and analysis can provide new insights into the interpretation of geophysical data from the oceanic crust at which pore‐fluid plays key roles in various geodynamic activities.
The Main Himalayan Thrust Beneath Nepal and Southern Tibet Illuminated by Seismic Ambient Noise and Teleseismic P Wave Coda Autocorrelation
Authors: Thapa Hari Ram , Pachhai Surya , Aoudia Abdelkrim , Manu‐Marfo Daniel , Priestley Keith , Mitra Supriyo
Published: June 2023

Nepal is an actively deforming region due to its tectonic setting that hosts destructive earthquakes including the recent 2015 Mw 7.8 Gorkha earthquake. To better understand the physics of earthquakes and better assess the seismic hazard in the region, a highly resolved 3‐D structure of the crust is essential. This study presents a new 3‐D S‐wave velocity structure of the crust using ambient noise tomography (ANT). In relation to the 2015 earthquake, we show that the lateral variation of S‐wave velocity likely controls the rupture propagation and arrest. This study further constrains crustal discontinuities beneath Nepal including the Main Himalayan Thrust (MHT) using teleseismic P‐wave coda autocorrelation. The MHT geometry correlates well with sizeable low S‐wave velocity zones obtained from the ANT and separated by two ramps. The southernmost first ramp is where the 2015 Gorkha earthquake nucleated that we map up to the source model of the 1934 historical earthquake in Eastern Nepal. The northernmost second ramp is adjacent to the mid‐crustal low velocity zone beneath south Tibet. In between the two ramps, we interpret the horizontal low velocity zone as the interseismic creeping patch of the MHT with down‐dip extent of 50–70 km length and 90–100 km in correspondence with the Mw 7.8 2015 and 8.4 1934 source models, respectively. A systematic mapping of the low‐velocity zones in relation to the MHT integrated with GPS geodesy along with the respective slip from individual past earthquake ruptures can help decipher the paradox of maximum Himalayan earthquake magnitudes.
Relationship Between the Aerosol Loadings Over the Bay of Bengal and the Arabian Sea in the Early Summer and Asian Monsoon Rainfall Anomalies, and the Role of SST Anomalies in the Indian Ocean
Authors: Zhang Yongsheng , Zhao Xuepeng , Zhang Huai‐Min
Published: June 2023

Two relatively long‐term satellite aerosol products during 1983–2020 and 2000–2020 are employed to investigate interannual relationships between anomalous aerosol loadings over the Bay of Bengal (BoB) and Arabian Sea (AS) in the early summer and Asian monsoon rainfall anomalies. It is shown that increased aerosol loading (IAL) over the BoB is primarily attributed to an intensified upstream aerosol transport by anomalous subtropical westerly winds and coincides with local sea surface temperature (SST) cooling due to intensified prevailing wind and the aerosol dimming effect, and vice versa. A deficient rainfall in India tends to concur with a BoB IAL while excessive rainfall with an AS IAL in May and June. In June, a BoB IAL coincides with significantly deficient rainfall in the southwestern China‐Huaihe River Basin primarily linked to an anomalous cyclone off the coast of Southeast China. Meanwhile a related overturning of Walker Circulation is identified to be driven by the contrast of anomalous convective activity between the southeastern Indian‐BoB and the South China Sea‐Philippine Sea. An AS IAL is associated with air warming in North India due to an elevated aerosol semi‐direct effect and remote forcing that reinforces the meridional air temperature gradient. The IAL over the respective BoB and AS in June are both preceded by cold SST anomalies in the western Indian Ocean that can be traced back to the preceding winter, but the corresponding atmospheric circulations driving aerosol‐monsoon interactions differ distinctly. The above aerosol‐monsoon relationships are sustained primarily during 2000–2020 and vague during 1983–2020.
A Hierarchical Temporal Scale Framework for Data‐Driven Reservoir Release Modeling
Authors: Longyang Qianqiu , Zeng Ruijie
Published: June 2023

As an important anthropogenic interference in the hydrologic cycle, reservoir operation behavior remains challenging to be properly represented in hydrologic models, thus limiting the capability of predicting streamflow under the interactions between hydrologic variability and operational preferences. Data‐driven models provide a promising approach to capture relationships embedded in historical records. Similar to hydrologic processes that vary across temporal scales, reservoir operations manifest themselves at different timescales, prioritizing different operation targets to mitigate streamflow variability at a given time scale. To capture the interaction of reservoir operation across time scales, we proposed a hierarchical temporal scale framework to investigate the behaviors of over 300 major reservoirs across the Contiguous United States with a wide range of streamflow conditions. Data‐driven models were constructed to simulate reservoir releases at monthly, weekly, and daily scales, where decisions at short‐term scales interact with long‐term decisions. We found that the hierarchical temporal scale configuration could compensate for the absence of key explanatory variables as model inputs, thereby efficiently capturing the release decisions of reservoirs situated in the west. Model‐based sensitivity analysis shows that for more than one‐third of the studied reservoirs, the release schemes, as a function of decision variables, vary at different time scales, suggesting that operators commonly face complicated trade‐offs to serve multiple designed purposes. The proposed hierarchical temporal scale approach is flexible to incorporate various data‐driven models and decision variables to derive reservoir operation rules, providing a robust framework to understand the feedback between natural streamflow variability and human interferences across time scales.
On the Capabilities of Emerging Nonintrusive Methods to Estimate Bedform Characteristics and Bedload Rates
Authors: Muste M. , You H. , Kim D. , Fleit G. , Baranya S. , Tsubaki R. , Abraham D. , McAlpin T. O. , Jones K. E.
Published: June 2023

A new measurement protocol, labeled Acoustic Mapping Velocimetry (AMV), has been successfully tested for in‐situ estimation of bedload transport features in sandy beds. The AMV has proven efficient in using the dune‐tracking method (DTM) for characterizing the bedform geometry and dynamics as well as for estimation of the rates of bedload transport. Given the novelty of the AMV protocol and its extensive reliance on multiple site‐specific assumptions and user‐defined parameters, a comparison of this emerging technique with other three non‐intrusive DTM‐based methods and analytical predictors is attempted in this paper. The comparison highlights that the AMV estimates are within 22% of the estimates with the other non‐intrusive protocols and up to 98% different from analytical predictions. The observed differences are related to the possible sources of uncertainty in the AMV workflows and to the means to reduce their impact on the targeted estimations.
East African Monsoon as a Drawbridge for the Circumnavigation of Madden–Julian Oscillation Events
Authors: Hagos Samson , Jung Jia , Ma Po‐Lun , Lubis Sandro W. , Balaguru Karthik , Chang Chuan‐Chieh (Jay) , Leung L. Ruby
Published: June 2023

The seasonality of circumnavigation of Madden–Julian Oscillation (MJO) events is examined using 42 years of observations, reanalysis, and global model simulations. MJO events are most likely to propagate across the Atlantic Ocean, Africa and back to the equatorial Indian Ocean relatively unweakened during March–April–May and to a lesser extent during September–October–November. During these seasons, referred to as the “long‐rain” and “short‐rain” periods of East African Monsoon (EAM), precipitation is near the equator and extends farthest east toward the Indian Ocean. Moisture budget analysis of a circumnavigating MJO event under real and hypothetical seasonally varying background conditions indicates that the seasonal zonal movement of the zonal component of the background circulation regulates the moistening of MJO crossing from Eastern Africa to the Indian Ocean. Ensembles of Energy Exascale Earth System Model simulations of the MJO event under idealized seasonally varying background state confirm the observed drawbridge‐like role of the EAM in the propagation of MJO.
Contributions of Climate Change and ENSO Variability to Future Precipitation Extremes Over California
Authors: Huang Xingying , Stevenson Samantha
Published: June 2023

The El Niño/Southern Oscillation (ENSO) affects the occurrence frequency and intensity of extreme precipitation through modulations of regional heat and moisture fluxes. California experiences particularly strong ENSO influences and models project different to its extreme precipitation. It remains unclear how diverse projections of future precipitation extremes relate to inter‐model differences for those changing signals. Here, we use “large ensemble” simulations with multiple climate models along with the Coupled Model Intercomparison Project Phase 5 to investigate the range of precipitation extreme changes over California and the influences from ENSO‐related teleconnections. We found that precipitation amount increases are much larger during El Niño relative to La Niña years, mainly caused by the differences in frequency of extreme events during different phases. The ENSO‐driven effect is even larger than the overall climate change signal for the most extreme events, implying uncertainties from inter‐model differences in ENSO‐related SST variability for extreme precipitation changes.
Ice Concentration Scaling Laws for Freshwater Lakes in Numerical Weather and Climate Prediction
Authors: MacKay Murray D.
Published: June 2023

If lake ice is assumed to deform and fail as a linear viscoelastic material under the action of wind stress, then a simple ice concentration scaling law can be constructed suitable for one‐dimensional lake models embedded within environmental prediction systems. Most 1‐D lake models assume no ice mechanics at all, while others adapt the viscous‐plastic rheology common in ice‐ocean models for the purpose of estimating ice fraction. Elastic buckling is generally disregarded as a significant failure mechanism in ice under low stress conditions at geophysical scales. However, by adding viscosity to the constitutive equation, the conditions for viscoelastic buckling seem quite plausible over a wide range of lake size and ice thickness. An ice concentration scaling law based on this process is evaluated here in multiannual simulations over North America and found to produce superior ice phenology statistics compared with simulations based on plastic failure or no ice mechanics.
Unlocking the monolithic integration scenario: optical coupling between GaSb diode lasers epitaxially grown on patterned Si substrates and passive SiN waveguides
Authors: Remis Andres , Monge-Bartolome Laura , Paparella Michele , Gilbert Audrey , Boissier Guilhem , Grande Marco , Blake Alan , O’Faolain Liam , Cerutti Laurent , Rodriguez Jean-Baptiste , Tournié Eric
Published: June 2023

Silicon (Si) photonics has recently emerged as a key enabling technology in many application fields thanks to the mature Si process technology, the large silicon wafer size, and promising Si optical properties. The monolithic integration by direct epitaxy of III–V lasers and Si photonic devices on the same Si substrate has been considered for decades as the main obstacle to the realization of dense photonics chips. Despite considerable progress in the last decade, only discrete III–V lasers grown on bare Si wafers have been reported, whatever the wavelength and laser technology. Here we demonstrate the first semiconductor laser grown on a patterned Si photonics platform with light coupled into a waveguide. A mid-IR GaSb-based diode laser was directly grown on a pre-patterned Si photonics wafer equipped with SiN waveguides clad by SiO2. Growth and device fabrication challenges, arising from the template architecture, were overcome to demonstrate more than 10 mW outpower of emitted light in continuous wave operation at room temperature. In addition, around 10% of the light was coupled into the SiN waveguides, in good agreement with theoretical calculations for this butt-coupling configuration. This work lift an important building block and it paves the way for future low-cost, large-scale, fully integrated photonic chips.