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The structural characteristics and driving mechanism of collaborative innovation netw...
Wang Yanmei
Chen Yusheng

Wang Yanmei

and 3 more

March 22, 2023
It is challenging for a single development subject to complete complex scientific research tasks due to the peculiarities of saline-alkali land. Collaborative innovation and cooperation between development subjects are increasingly vital. This paper first constructs an undirected weighted collaborative innovation network from the upstream, midstream, and downstream levels of technological innovation for saline-alkali land development, analyzing the network’s structural characteristics and spatial distribution features. Then uses ERGM to explore the internal and external driving mechanism for network formation from network self-organization, subject characteristics, and exogenous environmental factors. The results demonstrate that the distribution of collaborative innovation networks for saline-alkali land development is relatively uniform. However, there are also clusters, and the clusters are mostly centered on universities and scientific research institutions. Both the development subjects and clusters present regional features. Centrality and transitivity are crucial in the internal driving mechanism. In the external driving mechanism, the Matthew effect is modest, and the Homozygous effect is considerable; Organizational and technical proximity play a positive role; Geographical and institutional proximity play a blocking role. This study also provides practical enlightenment for encouraging horizontal and vertical collaborative innovation of sustainable development of saline-alkali land.
Improved design and Implementation of Personal Location Beacon
Mi Liao
Guigen Nie

Mi Liao

and 3 more

February 16, 2023
This letter improves the Personal Location Beacon( PLB), designs and implements a prototype personal maritime emergency radio beacon. Unlike the existing PLB, it is compatible with the traditional global search and rescue system( COSPAS-SARSAT) and BeiDou search and rescue system, the vital signs of people monitoring and reporting functions. After the PLB transmits distress information, the Beidou receiver works. The Beidou receiver receives information from the Rescue Centre and controls whether the PLB transmits the distress information again, reducing unnecessary emissions, thereby reducing the average power consumption of the PLB and extending the working time of the PLB. Measurements show that the current is 79mA in the state of receiving Beidou information, and the 7000mAh 7.4 V lithium battery can send distress messages to COSPAS Rescue Centre and Beidou Rescue Centre 200 times each, and the distress message contains the vital signs of people in distress. The vital sign is the temperature information. Ideally, the 7000mAh 7.4V lithium battery can support the continuous working time of the market for 48 hours.
Novel Tape-Splint Tarsorrhaphy Technique to Aid in the Diagnosis of Exposure Keratopa...
Soha Noorani
Dooho Kim

Soha Noorani

and 1 more

March 22, 2023
Introduction:Floppy Eyelid Syndrome (FES) describes the disease process whereby extreme laxity of the eyelid can lead to recurrent irritation of the ocular surface and corresponding palpebral keratoconjunctivitis1,2. Clinical exam characteristically reveals an eyelid that is easy to evert with traction superiorly2. However, FES can masquerade as conditions such as dry eye syndrome, keratitis, conjunctivitis, and dermatochalasis1-3. Incidence in the general population has been estimated to range from 2.3% to 15.8%, though notably it may not always be correctly diagnosed and may be more common1,2.We describe a case of unilateral and chronic keratoconjunctivitis unresponsive to standard medical therapy. Applying upward traction on the upper eyelid confirmed the diagnosis, as it revealed extensive laxity of the tarsal plate with resultant lagophthalmos and exposure keratopathy. Tape splint tarsorrhaphy (TST) has been recently described as a novel and non-invasive treatment modality for persistent corneal epithelial defects4. In this case, the TST was used as a novel and non-invasive diagnostic and temporizing tool to splint the eyelid down to address exposure keratopathy from lagophthalmos. Resolution of signs and symptoms was diagnostic and therapeutic confirmation that the keratoconjunctivitis resulted from the lagophthalmos and FES. This is the first such report to our knowledge discussing the specific use of this technique to more effectively diagnose refractory keratoconjunctivitis due to lagophthalmos and FES.
Erector Spinae Plane (ESP) Block Decreases Narcotic Requirement in Patients Undergoin...
Himani V. Bhatt
Jane Gui

Himani V. Bhatt

and 10 more

March 22, 2023
Introduction: Providing adequate analgesia during subcutaneous ICD implantation can be a challenge. The use of regional techniques such as erector spinae plane (ESP) block can provide both analgesia and attenuate the risk of opioid use especially in high-risk patient populations. Methods: This was a single center, prospective study of patients undergoing SICD implantation from February 2020 to February 2022. Patients were older than 18 years of age and randomly assigned to receive ESP block or traditional wound infiltration. The primary outcome was the overall use of perioperative analgesic medications in the ESP block versus the surgical wound infiltration group. Descriptive data are reported as count, mean, or median, as appropriate. For group comparisons, Fisher’s exact test was used for categorical variables; the student t-test was used for normally distributed continuous variables, and the Krustal-Wallis test was used for skewed continuous variables, as appropriate. Results: 24 patients were enrolled in the study. 11 patients received only wound infiltration and 13 patients received left ESP block. A significant reduction of intraoperative fentanyl use was observed in the ESP block. The overall postoperative day zero fentanyl use was also significantly decreased in the ESP group. The day to discharge was shorter in the ESP block group. Conclusion: This feasibility study showed that ESP block is both a safe and effective technique and demonstrated a significant decrease in intraoperative and postoperative opioid consumption that may be of clinical benefit in high risk patients. Larger studies are needed to further validate its use.
A multilevel mechanistic model of diversity change
William Godsoe
Warwick Allen

William Godsoe

and 8 more

March 22, 2023
Changes in biodiversity reflect processes acting on the success of individual species at multiple spatial scales, including in communities, biogeographic regions, and globally. This complexity makes it difficult to analyse the mechanisms shaping diversity change using traditional approaches. To resolve this, we propose a novel approach to partition total biodiversity changes according to mechanisms reflecting species' success at multiple scales. We apply this approach to study changes in the diversity of invertebrate herbivores from a large-scale, plant community experiment. This partitioning showed that rapid changes in the relative abundances of individual species resulted in surprisingly small changes in diversity across scales. Our novel analytical method reveals how strong ecological effects at different hierarchical levels can counteract each other, resulting in weak effects on diversity across broad spatial scales.
Delineating Expressional Difference in the Blood Mononuclear Cells between Healthy an...
Romana Ishrat
Anam Farooqui

Romana Ishrat

and 4 more

March 22, 2023
Turner Syndrome (TS) is a rare disorder associated either with complete or partial loss of one X chromosome in women. Comparing the healthy and individuals with Turner Syndrome may help elucidate the mechanisms involved in TS pathophysiology. Gene expression differences between healthy and individuals with Turner Syndrome were characterized using the systems-biology approach of weighted gene coexpression network analysis (WGCNA) on 182 microarray peripheral mononuclear blood samples (PBMC). The co-expression networks of healthy and TS had scale-free topology that ensures network robustness. In the process, five modules were preserved between healthy and TS, which carry several genes common in each module. Previously reported genes of TS, specifically, PTPN22, RPS4X, CSF2RA, and TIMP1 were missing in their respective modules. Dysfunction, differential expression, or absence of these genes could lead to a progressive disruption of molecular pathways leading to the pathophysiology of TS. Indeed, we observed a significant difference in the functions of these modules when compared within and across the healthy and TS samples. We identified 4 clusters in the PPI network constructed from the top 15 K ME enriched in significant functions. Overall, our work highlights the potential molecular functions, pathways, and molecular targets of TS that can be exploited therapeutically in the human health care system.
Defining dyssynchrony: The ongoing search for cardiac resynchronization therapy “resp...
Chinmaya Mareddy
Pamela Mason

Chinmaya Mareddy

and 1 more

March 22, 2023
Defining dyssynchrony: The ongoing search for cardiac resynchronization therapy “response”Chinmaya Mareddy, MD and Pamela K. Mason, MDUniversity of Virginia Health System, Charlottesville, VACorresponding Author:Pamela K. Mason, MDProfessor of MedicineUniversity of Virginia Health SystemBox 800158Charlottesville, VA 22908434-924-2465Pkm5f@virginia.eduThere are no relevant disclosures.There are no sources of financial support.The first trial to demonstrate the benefits of cardiac resynchronization therapy (CRT) was published in 2001. The single-blind crossover study demonstrated significant improvement in quality of life, NYHA class, and 6 minute walk test for patients with a left ventricular ejection fraction less than 35%, NYHA class III, an enlarged left ventricle, and a QRS duration greater than 150 ms.1 CRT represented an exciting advancement in cardiac implantable electronic device (CIED) therapy. While implantable cardioverter defibrillators (ICDs) had been in use for decades and represented a reliable, life-saving measure to treat fatal ventricular arrhythmias, for the first time, there was a device therapy that could improve quality of life for heart failure patients. The CARE-HF trial went on to demonstrate reduction in hospitalization and mortality in a similar population, and subsequent studies, such as MADIT-CRT suggested that the benefits extended to patients with NYHA class I or II.2,3While there was quick adoption of CRT and over the years and many patients have benefitted, it quickly became clear that there were unresolved issues and questions.4 First, there were patients who could not receive a coronary sinus pacing lead. This was predominantly due to variation in the coronary sinus anatomy and phrenic nerve stimulation. Developments such as quadripolar left ventricular pacing leads and improved sheath design have certainly reduced the number of failed implants, however, they will never be completely eliminated. Second, despite successful implants in “good” locations, some patients simply did not have clinical improvement. Further work identified subgroups that were more likely to respond, particularly those with a wide left bundle branch block (LBBB); however, even now, only about 70% of patients who meet generally accepted criteria for CRT experience improvement after a successful implant. Finally, while symptom improvement was the standard measure for most studies, there were patients who were “super responders” who actually developed improvement in their left ventricular ejection fraction after CRT, and it is difficult to predict which patients might receive this advantage.5As the data increasingly have shown that patients with LBBB are more likely to benefit from CRT compared to right bundle branch block or non-specific intraventricular conduction delays, most society guidelines require a true LBBB to meet a class I indication for CRT.6,7 The difficulty with using LBBB as a metric for CRT candidacy is that defining it has been controversial. Multiple criteria have been proposed. In their 2021 guidelines statement for pacing and CRT, the European Society of Cardiology (ESC) altered their definition of LBBB.8 Specifically, they added the requirement of notching or slurring in 2 adjacent leads to define a true LBBB, thus making the definition of LBBB more restrictive. In addition, the 2021 guidelines also moved patients with narrower LBBB (120-149 ms) to a Class IIa recommendation. This obviously has important implications as to guidelines recommendations and benefits of CRT.In this edition of the Journal of Cardiovascular Electrophysiology, Rijik, et al present a retrospective analysis of 1202 consecutive patients from a registry who received a CRT device between 2000 and 2015. They applied the 2013 European Society of Cardiology (ESC) definition of left bundle branch block (LBBB) to the population and then the 2021 ESC definition of LBBB and assessed how patients would have qualified for CRT based upon those criteria. In addition, the authors reviewed the actual patient response to CRT in comparison to the guidelines recommendation for CRT implantation by 2013 and 2021 guidelines. Applying the more stringent 2021 criteria dramatically reduced the number of patients with a true LBBB from 80.9% of the population to 31.6%. This moved many patients out of a class I indication for CRT. In addition, they found that the 2013 criteria better discriminated the patients who actually did respond to CRT therapy. When evaluating a combined end point of transplantation, left ventricular assist device implantation, and mortality, the patients with a LBBB by the 2013 criteria and a QRS duration > 150 ms had significant benefit and those without did not. The same was true for echocardiographic response. When applying the 2021 criteria, differences were not seen between the two groups, implying that many patients who no longer had LBBB by 2021 guidelines still benefitted from CRT.The authors should be congratulated for adding important understanding to how we think about CRT and patient selection. These data show that employing a more strict definition of LBBB does not discriminate those who are most likely to benefit from CRT and might discourage implantation in patients who may benefit. The ESC is not the only society that has supported a more restrictive definition of LBBB.9 It is difficult to know how these definitions and guidelines directly influence practice, but we don’t want to risk denying patients an important therapy that could improve their quality and quantity of life. It is also difficult not to reflect that this paper shows both how far we have come with device therapy for our heart failure patients and how much further we have to go. We have been implanting CRT devices for over 20 years. Many patients have benefitted from this novel therapy, and yet there is so much that we don’t know.We must consider what the role for CRT will be in the future. Novel methods of leadless left ventricular pacing are being developed.10 There are observational and retrospective data suggesting that left bundle branch area pacing may be as good or better than CRT in improving clinical outcomes and heart function.11,12 Further, with experience, it is potentially faster to implant a left bundle area lead compared to a coronary sinus lead, and there has been wide early adoption of the technique compared to His bundle pacing. A multi-center, randomized controlled trial evaluating conduction system pacing compared to CRT should start enrolling soon and we should have more information in the coming years.13 It is possible to envision a future where coronary sinus pacing leads are no longer the norm in this patient population. It is also unlikely that the need for successful coronary sinus lead placement will be completely eliminated. Regardless of what the future holds, the insights from CRT studies, the effects on hemodynamics, electrical function, and outcomes will inform new directions.ReferencesCazeau S, Leclercq C, Lavergne T, et al. Affects of multisite biventricular pacing in patients with heart failure and intraventricular conduction delay. N Engl J Med2001;344:873-80.Cleland JGF, Daubert JC, Erdmann E, Freemantle N, et al. The effective cardiac resynchronization on morbidity and mortality and heart failure. N Engl J Med 2005;352:1539-1549.Moss AJ, Hall WJ, Cannom DS, et al. Cardiac resynchronization therapy for prevention of heart failure events. N Engl J Med2009;361:1329-1338.Sieniewicz BJ, Gould J, Porter B, et al. Understanding nonresponse to cardiac resynchronisation therapy: common problems and potential solutions. Heart Fail Rev 2019;24:41-54.Liang Y, Wang Q, Zhang M, et al. Cessation of pacing in super-responders of cardiac resynchronization therapy: a randomized controlled trial. J Cardiovasc Electrophysiol 2018; 29:1548-1555.Brignole M, Auricchio A, Baron-Esquivias G, et al. 2013 ESC guidelines on cardiac pacing and cardiac resynchronization therapy: The task force on cardiac pacing and resynchronization therapy of the European society of Cardiology (ESC). Developed in collaboration with European heart rhythm Association (EHRA). Eur Heart J 2013;34:2281-329.Tracy CM, Epstein AE, Barbar D, et al. 2012 ACCF/AHA/HRS focused update of the 2008 guidelines for device based therapy of cardiac rhythm abnormalities. Circulation 2012;126:1784-1800.Glikson M, Nielsen JC, Kronborg MB, et al. 2021 ESC guidelines on cardiac pacing and cardiac resynchronization therapy: developed by the task for sudden cardiac pacing and cardiac resynchronization therapy of the European Society of Cardiology (ESC) with a special contribution of the European Heart Rhythm Association (EHRA).Eur Heart J 2021;42:3427-3520.Surawicz B, Childers R, Deal BJ, et al. AHA/ACCF/HRS recommendations for the standardization and interpretation of the electrocardiogram: Part 3: intraventricular conduction disturbances: A scientific statement from the American Heart Association Electrophysiology and Arrhythmias Committee, Council on Clinical Cardiology; the American College of Cardiology Foundation; and the Heart rhythm Society: Endorsed by the International Society for Computerized Electrocardiography. Circulation 2009; 119:e235-40.Okabe O, Hummel JD, Bank AJ, et al. Leadless left ventricular stimulation with a WISE-CRT system: Initial experience results from the phase 1 of the SOLVE-CRT study (non randomized, role in phase).Heart Rhythm 2020; S1547-5271(21)01808-7.Vijayaraman P, Zalavadia D, Haseeb A, et al. Clinical outcomes of conduction system pacing compared to biventricular pacing in patients requiring cardiac resynchronization therapy. Heart Rhythm. 2022;19(8):1263-1271.Ezzeddine FM, Pistiolis SM, Pujol-Lopez M, et al. Outcomes of Conduction System Pacing for Cardiac Resynchronization Therapy in Patients with Heart Failure: A Multicenter Experience. Heart Rhythm. Published online February 24, 2023. doi:10.1016/j.hrthm.2023.02.018.Wang Y, Zhu H, Hou X, et al. Randomized trial of left bundle branch vs biventricular pacing for cardiac resynchronization therapy. J Am Coll Cardiol 2022;80:1205-1216.
Functionalization of indium oxide for empowered detection of CO2 over an extra-wide r...
ARIANNA ROSSI
Barbara Fabbri

ARIANNA ROSSI

and 10 more

March 22, 2023
Carbon capture, storage and utilization have become familiar terms when discussing climate change mitigation actions. Such endeavors demand the availability of smart and inexpensive devices for CO2 monitoring. To date, CO2 detection relies on optical properties and there is a lack of devices based on solid-state devices, which can be miniaturized and easily made compatible with IoT platforms. With this purpose, we present an innovative semiconductor as functional material for CO2 detection. Nanostructured In2O3 films, functionalized by Na, proves to enhance the surface reactivity of pristine oxide so much that even rather stable a molecule as CO2 is reduced. An advanced operando equipment based on surface-sensitive diffuse infrared Fourier transform is used to investigate its improved surface reactivity. The role of sodium is to increase the concentration of active sites such as oxygen vacancies and, in turn, to strengthen CO2 adsorption and reaction at the surface. It results in a change in film conductivity, i.e., in transduction of a concentration of CO2. The films exhibit excellent sensitivity and selectivity to CO2 over an extra-wide range of concentration (250-5000 ppm), which covers most indoor and outdoor applications with marginal influence by environmental humidity.
A Case of Splenogonadal Fusion in the Left Testis
ting zhou

ting zhou

March 22, 2023
A document by ting zhou. Click on the document to view its contents.
Exact delay range for the stabilization of linear systems with input delays
Lin Li
Ruilin Yu

Lin Li

and 1 more

March 22, 2023
A document by Lin Li. Click on the document to view its contents.
Interfacial Engineering of Vertically-stacked Graphene/h-BN Heterostructure as an Eff...
Yuying Zhao
Xiang Xu

Yuying Zhao

and 10 more

March 22, 2023
Recently, in-plane graphene/h-BN (G/h-BN) heterostructure was reported to be the catalytic activity for H2O2 synthesis by 2 e- oxygen reduction reaction (ORR). However, there is rare report for the vertically-stacked G/h-BN heterostructure, which refers to the stacking of graphene domains on the surface of h-BN. Herein, a simulated chemical vapor deposition method was proposed for fabricating abundant vertically-stacked G/h-BN heterostructure by in-situ growing graphene quantum dots (GQDs) on porous h-BN sheets. The catalytic performance of our vertically-stacked heterostructure catalyst is superior to the reported carbon-based electrocatalysts in an alkaline environment, with the H2O2 selectivity of 90%-99% in a wide potential range (0.35 V-0.7 V vs. RHE), over 90% faradaic efficiency and high mass activity of 1167 mmolgcatalyst-1 h-1. The experimental results and density functional theory simulation verifies that the vertically-stacked heterostructure possesses greatly catalytic performance for 2 e- ORR and the edge B atoms in the B-centered AB stacking model are the most active catalytic sites. This research well demonstrates the promising catalytic activity for the vertically-stacked G/h-BN heterostructure and provide a facile route for fabricating other vertically-stacked heterostructures.
Successful ablation of a right epicardial accessory pathway via the right ventricular...
Zhijun Zhang
Chang Sheng Ma

Zhijun Zhang

and 5 more

March 22, 2023
Introduction: We describe one rare case of successful ablation of a right epicardial accessory pathway (AP) via the right ventricular diverticulum in a patient with Wolff-Parkinson-White syndrome. Methods: A 42-year-old woman being referred to the hospital for a catheter ablation of a Wolf-Parkinson White syndrome. Earliest activation was shown to be present in the region of the tricuspid annulus. However, ablation had no effect on the AP. Results: We decided to do a selected angiography, in which a big diverticulum near to the right tricuspid annulus was shown to be present. Ablation in this region successfully repressed the AP without any recurrences within a follow-up period of 12 months. Conclustion: The ventricular diverticulum mediated AP is a novel variant of pre-excitation. It can serve as an anatomical substrate of supraventricular tachycardia, and can be ablated endocardially using an irrigation tip catheter within the diverticulum.
Combination of transcatheter arterial chemoembolization and anti-PD-L1 liposomes ther...
Jie Li
Lijuan Zhang

Jie Li

and 5 more

March 22, 2023
Background To study the effects of combination TACE and anti-PD-L1 liposome drug in treating HCC in mice models. Methods We constructed the liposome drug with lecithin and cholesterol and mannitol, etc. Besides, the HCC mice model was established through abdominal subcutaneous injection HepG2 cancer cells in SD mice, then the PE-10 polyethylene catheter was used for TACE therapy. The SD mice were separately received TACE treatment, avelumab liposome drug therapy, and TACE combined with avelumab liposome drug therapy. Results The liposomes drug was successfully constructed with a diameter of 125.5 nm. After the mice received TACE and (or) immunotherapy, the combined liposome drug therapy significantly reduced the volume of hepatic carcinoma tissues, besides, the apoptotic rates of hepatic carcinoma cells in the combined liposome drug treatment group was increased obiviously compared with other groups. Moreover, the protein TGFβR2 located in the cellular membrane was obiviously down-regulated in the combined liposome drug therapy, whilst, the expression of SMAD7 and PTPN14 was up-regulated in the treatment groups compared with the mice without treatment, besides, the protein PTPN14 was mainly located in the nucleus. Additionally, the mRNA expression of genes SNAI1 and Vimentin was significantly down-regulated in the combined liposome drug therapy. Conclusion Combination of transcatheter arterial chemoembolization and anti-PD-L1 liposome drug therapy significantly suppressed hepatocellular carcinoma proliferation and metastasis in mice models.
Maximizing Penetration Testing Success with Effective Reconnaissance Techniques using...
Sheetal Temara

Sheetal Temara

March 22, 2023
ChatGPT is a generative pretrained transformer language model created using artificial intelligence implemented as chatbot which can provide very detailed responses to a wide variety of questions. As a very contemporary phenomenon, this tool has a wide variety of potential use cases that have yet to be explored. With the significant extent of information on a broad assortment of potential topics, ChatGPT could add value to many information security uses cases both from an efficiency perspective as well as to offer another source of security information that could be used to assist with securing Internet accessible assets of organizations. One information security practice that could benefit from ChatGPT is the reconnaissance phase of penetration testing. This research uses a case study methodology to explore and investigate the uses of ChatGPT in obtaining valuable reconnaissance data. ChatGPT is able to provide many types of intel regarding targeted properties which includes Internet Protocol (IP) address ranges, domain names, network topology, vendor technologies, SSL/TLS ciphers, ports & services, and operating systems used by the target. The reconnaissance information can then be used during the planning phase of a penetration test to determine the tactics, tools, and techniques to guide the later phases of the penetration test in order to discover potential risks such as unpatched software components and security misconfiguration related issues. The study provides insights into how artificial intelligence language models can be used in cybersecurity and contributes to the advancement of penetration testing techniques.
An Empirical Analysis of Approach-Based Metrics Model for Architectural Erosion Detec...
AHMED BAABAD
HAZURA BINTI ZULZALIL

AHMED BAABAD

and 3 more

March 22, 2023
Software architecture determines success or failure in the domain of software development and design. As a system evolves, software architecture erodes. This phenomenon is called architectural erosion. Several studies that focused on various approaches to the problem of architectural erosion have been conducted. As a direct consequence of this, the metrics strategy has emerged as the most widely used solution for architectural erosion. However, providing a comprehensive perception of the elements required to evaluate the phenomenon of architectural erosion with an acceptable level of quality is a challenge. The primary goals of this research, which drew from the prior literature about identifying architectural erosion, were to (1) determine whether various adopted measures approaches determine architectural erosion in order to develop a formal model, and (2) evaluate the construct reliability and construct validity of the model. This research presents a model based on the chosen measures approaches for identifying architectural degradation. This model can be used as the cornerstone for a formal definition of general approaches and adopted metrics. Data was collected from 130 software engineering professionals with experience in architecture erosion and software metrics via a questionnaire-based survey. Structural equation Modelling (SEM) was used to analyse construct reliability, construct validity, and research hypotheses. The results demonstrate a substantial association between all metrics approach classes and architectural erosion, except for architectural complexity and architectural technical debt. Both researchers and practitioners can significantly benefit from this model’s empirical assessment and evaluation, which includes a valuable information in this context.
The analytic solution of the fractional Rosenau--Hyman model in Liouville-Caputo sens...
Suleyman Cetinkaya
Ali Demir

Suleyman Cetinkaya

and 1 more

March 22, 2023
The purpose of this work is to achieve the analytic solution of non-linear Liouville-Caputo fractional initial value problem including time fractional Rosenau–Hyman equation by means of ARA transform and iterative method. First of all, ARA transform is employed to reduce the problem into a simpler one. Then the series solution of the non-linear fractional initial value problem is acquired by applying iterative method which leads to the analytic solution of the Rosenau–Hyman equation (RHE) with initial condition. The obtained results verify that the combination of ARA transform with iterative method produces an effective method to tackle with non-linear fractional problems.
Dutch Flag Algorithm 2.0 for Quicksort
Dennis de Champeaux

Dennis de Champeaux

March 22, 2023
Dijkstra’s Dutch Flag algorithm (DFA) can be used as a member of a quicksort hybrid to deal with, among others, a ‘difficult’ segment. We first show that the DFA can be wrapped so that this combination (with insertion sort and heapsort) is a ‘decent’ sorter. Subsequently we describe a different implementation of the DFA with a similar wrapper and compare their performance. Thirdly we show how these ‘mini’ sorters can be included in a five member hybrid quicksort sorter and we explain their contributions. The combination has NlogN worst case complexity and for constant input it has linear complexity. We compare several of these versions favorably against quicksort versions we found in libraries.
Navigating gender at sea
Kay McMonigal
Natalya Evans

Kay McMonigal

and 12 more

March 26, 2023
Fieldwork, including work done at sea, is a key component of many geoscientists' careers. Recent studies have highlighted the pervasive sexual harassment faced by women during fieldwork. However, transgender and gender diverse scientists face unique obstacles, which have not yet been studied. We partially fill this gap by sharing our experiences as transgender and gender diverse people. We have experienced sexual harassment, misconduct, privacy issues, and legal and medical struggles as we conduct seagoing work. We provide recommendations to make seagoing work safer to our communities. These recommendations are a starting point to make seagoing work more inclusive for all.
The Saharan dust plume: Current knowledge on the impact on health, human activities,...
Olaoluwa Omoniyi Olarewaju
Olufunke Omowumi Fajinmi

Olaoluwa Omoniyi Olarewaju

and 5 more

March 26, 2023
A massive amount of dust estimated at a million tons is released from the Sahara Desert each year into the atmosphere and travels over the North Atlantic Ocean, commonly referred to as the Saharan dust plume (SDP). With its ability to travel over very long distances across the sea, the SDP is of enormous global importance, affecting climatic processes, and playing a significant role in nutrient cycles, sedimentary cycles, and soil development. On the other hand, from an environmental health perspective, the SDP degrades air quality, posing serious health threats to humans, especially to people with lung conditions. Recent literature documents health issues, including respiratory and cardiovascular diseases and even death in extreme cases. Despite this knowledge, large uncertainties exist in our ability to predict future trends in Saharan dust emissions and model-projected atmospheric circulation patterns. Employing a comprehensive search of the recent literature, this study reviews present knowledge of the sources, composition and propagation dynamics of the SDP and the impact of its contained atmospheric particulates on health, ecosystems, and human activities to be able to formulate credible mitigation measures and unveil areas where further research is needed for improving on these formulations. A comprehensive list of the more recent references (mainly post-dating 2010) is assembled to aid the search process of those wanting to contribute to filling these important knowledge gaps.
Nyiragongo crater collapses measured by multi-sensor SAR amplitude time series
Delphine Smittarello
Raphael Grandin

Delphine Smittarello

and 8 more

March 26, 2023
Crater morphology at active volcanoes can change rapidly. Quantifying changes during the course of a volcanic unrest episode may help assess the level of volcanic activity. However, limitations such as crater accessibility, cloud cover or intra-crater eruptive activity may hamper regular optical or on-site crater monitoring. Here we use multi-sensor satellite Synthetic Aperture Radar (SAR) imagery to produce dense time series of quantitative indicators of crater morphological changes. High temporal resolution is achieved by combining images from a variety of sensors and acquisition modes, though the diversity of acquisition geometries (incidence angle, viewing direction, resolution…) prevents direct comparison between the different images. Using basic trigonometry assumptions, we develop PickCraterSAR, an open-access tool written in Python to measure crater radius and depth from SAR amplitude images in radar geometry. We apply our methodology to study the crater collapse associated with the May 2021 and January 2002 eruptions of Nyiragongo volcano. After the 2021 collapse, we estimate the maximum depth of the crater to be 850 m below the rim and the total volume to be 84$\pm$10 Mm$^3$ (270 m deeper but only 15-20 \% more voluminous than the post-2002 eruption crater). We also show that the 2021 crater collapse occurred progressively while a dike intrusion was migrating toward the south.
High-resolution simulations of the plume dynamics in an idealized 79°N Glacier cavity...
Markus Reinert
Marvin Lorenz

Markus Reinert

and 4 more

March 26, 2023
For better projections of sea level rise, two things are needed: an improved understanding of the contributing processes and their accurate representation in climate models. A major process is basal melting of ice shelves and glacier tongues by the ocean, which reduces ice sheet stability and increases ice discharge into the ocean. We study marine melting of Greenland’s largest floating ice tongue, the 79° North Glacier, using a high-resolution, 2D-vertical ocean model. While our fjord model is idealized, the results agree with observations of the meltrate and the overturning strength. Our setup is the first application of adaptive vertical coordinates to an ice cavity. Their stratification-zooming allows a vertical resolution finer than 1 m in the entrainment layer of the meltwater plume, which is important for the plume development. In a sensitivity study, we show that the buoyant plume at the ice–ocean interface is responsible for the bulk of basal melting. The melting almost stops when the plume has reached neutral buoyancy. There, the plume detaches from the ice tongue and transports meltwater out of the fjord. The detachment depth depends primarily on the ambient ocean stratification. Our results contribute to the understanding of ice–ocean interactions in glacier cavities. Furthermore, we suggest that our modeling approach with stratification-zooming coordinates will improve the representation of these interactions in global ocean models. Finally, our idealized model topography and forcing are close to a real fjord and completely defined analytically, making the setup an interesting reference case for future model developments.
Lateral Variations Across the Southern San Andreas Fault Zone Revealed from Analysis...
Hao Zhang
Haoran Meng

Hao Zhang

and 2 more

March 26, 2023
We image the shallow seismic structure across the Southern San Andreas Fault (SSAF) using signals from freight trains and trucks recorded by a dense nodal array, with a linear component perpendicular to SSAF and two 2D subarrays centered on the Banning Fault (BF) and Mission Creek Fault (MCF). Particle motion analysis in the frequency band 2-5 Hz shows that the examined traffic sources can be approximated as moving point sources that primarily induce Rayleigh waves. Using several techniques, we resolve strong lateral variations of Rayleigh wave velocities across the SSAF, including 35% velocity reduction across MCF towards the northeast. Additionally, we derive Q-values and find strong attenuation around the BF and MCF. We further resolve 10% mass density reduction and 45% shear modulus decrease across the MCF. These findings suggest that the MCF is the main strand of the SSAF in the area with important implications for seismic hazard assessments.
Positive Low Cloud Feedback Primarily Caused by Increasing Longwave Radiation from th...
Tomoo Ogura
Mark J Webb

Tomoo Ogura

and 2 more

March 26, 2023
Low cloud feedback in global warming projections by climate models is characterized by its positive sign, the mechanism of which is not well understood. Here we propose that the positive sign is primarily caused by the increase in upward longwave radiation from the sea surface. We devise numerical experiments that enable separation of the feedback into components coming from physically distinct causes. Results of these experiments with a climate model indicate that increases in upward longwave radiation from the sea surface cause warming and absolute drying in the boundary layer, leading to the positive low cloud feedback. The absolute drying results from decrease in surface evaporation, and also from decrease in inversion strength which enhances vertical mixing of drier free tropospheric air into the boundary layer. This mechanism is different from previously proposed understanding that positive low cloud feedback is caused by increases in surface evaporation or vertical moisture contrast.
Subglacial-discharge plumes drive widespread subsurface warming in northwest Greenlan...
Tom R Cowton
Donald A Slater

Tom R Cowton

and 2 more

March 26, 2023
Greenland’s glacial fjords modulate the exchange between the ice sheet and ocean, with the water properties adjacent to tidewater glaciers influencing the rate of submarine glacier melting and the export of glacially-modified waters to the shelf. Here we use a numerical plume model in conjunction with observations from proximal to 14 glaciers in northwest Greenland to assess the impact of subglacial-discharge-driven plumes on near-glacier water properties. We find that in late summer, waters emanating from glacial plumes often make up > 50 % of the fjord water composition at intermediate depths. These plume waters are comprised largely of upwelled Atlantic Water, warming the near-glacier water profile and likely increasing submarine melting. Our findings demonstrate the key role played by plumes in driving water modification in Greenland’s fjords, and the potential for simple models to capture these impacts across a range of settings.
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