bluuebunny/crossref_metadata_2025 huggingface dataset:
SO SÁNH GIỮA PHỐI HỢP CHT HAI XUNG VÀ CHT BA XUNG TRONG CHẨN ĐOÁN UNG THƯ TUYẾN TIỀN LIỆT
Authors: Lê Thanh Dũng , Nguyễn Duy Hùng , Nguyễn Thị Hải Anh
Published: February 2023

Mục tiêu: So sánh mức độ tin cậy và khả năng chẩn đoán ung thư tuyến tiền liệt (UTTTL) của cộng hưởng từ (CHT) hai xung và CHT ba xung sử dụng hệ thống phân loại PIRADs 2.1. Phương tiên và phương pháp: 82 bệnh nhân nghi ngờ UTTTL có chụp CHT 3.0T đa chuỗi xung bao gồm các xung T2W, DWI, DCE và có kết quả giải phẫu bệnh qua sinh thiết. Tổn thương được phân độ 1 đến 5 cho xung T2W và DWI, xếp âm tính hoặc dương tính cho DCE theo hệ thống PIRADs 2.1 và xác dịnh tổng điểm PIRADs toàn bộ cho 2 xung (T2W và DWI) và PIRADs toàn bộ cho 3 xung (T2W, DWI, DCE). Tiêu chuẩn sử dụng đối chiếu là kết quả giải phẫu bệnh sinh thiết 12 điểm. Kết quả: Trong số 82 bệnh nhân với 328 tổn thương, có 159 tổn thương có u và 169 tổn thương lành tính. Các giá trị độ nhạy, độ đặc hiệu, giá trị dự đoán dương tính, giá trị dự đoán âm tính của CHT 2 xung lần lượt là 86,8%; 96,4%; 95,8% và 88,6%; của CHT 3 xung lần lượt là 88,7%; 86,4%; 95,9% và 90%. Kết luận: Khi sử dụng hệ thống PIRADs 2.1, giá trị chẩn đoán của CHT 2 xung có thể coi là tương đương với CHT 3 xung trong xác định UTTTL. Chuỗi xung DCE nên được sử dụng như một chuỗi xung không bắt buộc, được chỉ định bổ xung tùy từng trường hợp củ thể.
NHẬN XÉT ĐẶC ĐIỂM LÂM SÀNG CÁC BỆNH NHÂN MẤT CÂN XỨNG MẶT
Authors: Võ Thị Minh Hảo , Nguyễn Thị Thúy Nga , Nguyễn Tấn Văn
Published: February 2023

Mục tiêu: Nhận xét đặc điểm lâm sàng của bệnh nhân mất cân xứng mặt. Đối tượng nghiên cứu: Nghiên cứu được thực hiện từ tháng 2/2022 đến tháng 12/2022, bằng phương pháp nghiên cứu mô tả cắt ngang của 33 người bệnh từ 16 tuổi đến khám vì mất cân xứng mặt tại bệnh viện Răng Hàm Mặt Trung ương Hà Nội, dựa vào phiếu hỏi bệnh, khám lâm sàng, phân tích ảnh mặt thẳng, ảnh mặt cười. Kết quả: Độ tuổi trung bình của nam tham gia nghiên cứu là 20,2 ± 4,02 tuổi và nữ là 23,1 ± 8,38 tuổi, 100% bệnh nhân bất cân xứng mặt có lệch cằm, trong đó bệnh nhân có tỷ lệ sai lệch cằm trái cao 70,6%, không có sự khác biệt giữa nam và nữ bị lệch cằm (p<0,05). Tỷ lệ bệnh nhân tham gia nghiên cứu bất cân xứng ngang mô mềm và lệch góc miệng lần lượt là 87,9% và 69,7%. Trong 33 bệnh nhân tham gia nghiên cứu, 21,2% bệnh nhân được đánh giá cắn chéo một bên, bệnh nhân cắn chéo hai bên là 48,5% và 30,3% không mắc phải triệu chứng này. Độ lệch cằm trung bình là 9,84±5,51mm. Độ lệch trung bình bất cân xứng ngang mô mềm và độ lệch góc miệng lần lượt là 10,07±7,9mm và 3,28±2,27mm. Tỷ lệ sai lệch cằm của các bệnh nhân bất cân xứng mặt bị lệch khớp cắn hạng I, II, III lần lượt là 15,2%; 9,1% và 75,8%. Tình trạng lệch khớp cắn hạng III là hay thường gặp nhất. Tỷ lệ bệnh nhân có lệch cằm thì đường đường giữa hàm dưới sẽ hầu hết bị lệch (84,9%), sự khác biệt có ý nghĩa thống kê được tìm thấy giữa nhóm bệnh nhân lệch cằm và có đường giữa hàm dưới bị lệch (p<0,01). Yếu tố giới tính không ảnh hưởng đến tình trạng bất cân xứng trên khuôn mặt của bệnh nhân (p>0,05). Thói quen đẩy lưỡi là yếu tố ảnh hưởng đến tình trạng sai lệch mặt của bệnh nhân. Kết luận: Bệnh nhân bất cân xứng mặt có 100% có lệch cằm. Đa số 84,9% các trường hợp có lệch cằm thì đường thì đường giữa hàm dưới cũng lệch (p<0,01). Yếu tố giới tính không ảnh hưởng đến tình trạng bất cân xứng trên khuôn mặt của bệnh nhân (p<0,05). Thói quen đẩy lưỡi là yếu tố ảnh hưởng đến tình trạng sai lệch mặt của bệnh nhân.
Evaluating Designs for Hyperparameter Tuning in Deep Neural Networks
Authors: Shi Chenlu , Chiu Ashley Kathleen , Xu Hongquan
Published: February 2023

The performance of a learning technique relies heavily on hyperparameter settings. It calls for hyperparameter tuning for a deep learning technique, which may be too computationally expensive for sophisticated learning techniques. As such, expeditiously exploring the relationship between hyperparameters and the performance of a learning technique controlled by these hyperparameters is desired, and thus it entails the consideration of design strategies to collect informative data efficiently to do so. Various designs can be considered for this purpose. The question as to which design to use then naturally arises. In this paper, we examine the use of different types of designs in efficiently collecting informative data to study the surface of test accuracy, a measure of the performance of a learning technique, over hyperparameters. Under the settings we considered, we find that the strong orthogonal array outperforms all other comparable designs.
Nabilone for the Treatment of Posttraumatic Stress Disorder: A 2023 Update
Authors: Young Calvin , MacDougall Danielle , Hamson Angie
Published: February 2023

One relevant systematic review of high methodological quality did not include any randomized controlled trials (RCTs) on the effectiveness of nabilone for the treatment of posttraumatic stress disorder (PTSD).

We did not find any evidence-based guidelines on the use of nabilone for adults with PTSD.
PARLIAMENTARY WAY OF FORMING GOVERNMENT IN FOREIGN COUNTRIES: COMPARATIVE AND LEGAL ANALYSIS
Authors:   Tashkent State University of Law, Hoshimkhonov Ahrorhon
Published: February 2023

This article discusses the parliamentary method, which is one of the modern methods of government formation. The views of legal scholars in this area are revealed and the constitutional and legal foundations for the formation of the highest executive body of foreign parliamentary countries, and its specific features are studied. Also, thanks to the analysis of legal documents on the formation of the government of the Republic of Uzbekistan, its important aspects are identified. A theoretical conclusion is made that the formation of the government of the Republic of Uzbekistan should be carried out on the basis of a parliamentary approach. The author’s conclusions about the establishment and implementation of constitutional procedures and principles for the resignation of the government and its members in parliamentary states are based on the following: the use of two methods of forming a government in foreign countries, namely parliamentary and non-parliamentary; the order of formation of the government and the ownership of the executive power depends primarily on the form of government of a particular state; fixing in the constitution important provisions for the formation of the government; government accountability to parliament and the head of state.
THE ROLE OF COLLECTIVE MANAGEMENT IN ENSURING COPYRIGHT PROTECTION IN UZBEKISTAN
Authors:   Tashkent State University of Law, Yuldashov Abdumumin
Published: February 2023

The article discusses the current state and processes of copyright protection in Uzbekistan, in particular, the role of organizations that manage property rights on a collective basis. It is known that according to the Law of the Republic of Uzbekistan “On Copyright and Related Rights”, authors, performers, producers of phonograms or other copyright holders of works of science, literature and art, in order to exercise their property rights, have the right to create organizations that manage their property rights on a collective basis. The article highlights the legal significance of the legal methods and means used by such organizations in the performance of their tasks and functions. Due to the fact that organizations that manage property rights on a collective basis are entitled to take any legal actions necessary to protect the rights they manage, the legal nature of these actions, the mechanisms for protecting the property and personal non-property rights of authors and right holders with highlights. The article also provides that an organization which manages property rights on a collective basis may agree with users on the amount of remuneration to be paid on behalf of the right holders and the basis of the powers arising from them, and other terms of contracts. Issues such as entering into agreements with users and negotiating with users the amount of remuneration for exercising the rights managed by the organization were also discussed. The conclusion based on the issue of improving the “institution” of collective copyright management in Uzbekistan is provided at the end of the article.
THE ROLE OF COMPLIANCE CONTROL SYSTEM IN PREVENTING CORRUPTION AND CONFLICT OF INTERESTS (EXAMPLE OF PUBLIC AND PRIVATE SECTORS)
Authors:   Tashkent State University of Law, Makhmudov Firuz
Published: February 2023

This article discusses the positive achievements and mechanisms for overcoming corruption and conflicts of interest-based on the requirements for modern civil servants and provides a detailed analysis of the implementation of internal control systems. The system of complex control and its capabilities, its historical development and its role in preventing corruption and conflicts of interest are scientifically investigated. The positive experience and opportunities for the implementation of the complex control system in foreign countries, international organizations, and non-governmental organizations have been analyzed through national and foreign literature. Through the analysis of normative and legal acts of the Republic of Uzbekistan, the tasks set for the introduction of a comprehensive control system, the current situation and legal gaps are studied on the example of the public and private sectors. The external factors to be taken into account in the implementation of the complex control system, and the possible risks have been studied on the basis of scientific sources. Based on national and foreign experience, scientific proposals and conclusions of scientists, opinions, suggestions, and recommendations on the effective organization of a comprehensive control system in the prevention of corruption and conflicts of interest in the country were put forward.
WRITTEN DISCURSIVE COMPETENCE AS A COMPONENT OF FOREIGN LANGUAGE COMMUNICATIVE COMPETENCE OF LAW UNIVERSITY STUDENTS
Authors:   Tashkent State University of Law, Zoyirova Dilsuz
Published: February 2023

The paper discusses written discursive competence as a main element of foreign language communicative competence of the students of Tashkent State University of Law. Indeed, written discursive competence is the writer’s ability to generate various types of discourse for involvement in written foreign language communication with the intended addressee in order to achieve the desired result, depending on the sociocultural setting and communicative task. Because written discursive competence is a complicated multicomponent phenomenon, its structure distinguishes a number of subcompetences, which are thoroughly discussed in the article. Prior to the discussion part, the author focuses on the definition of the terms “discourse” and “discursive competence”, relying on the perceptions of various scholars. Also, the differences of “discourse” and “text” are introduced accordingly, and the tasks for the formation of discursive competence of law students in this very context are outlined with their specific characteristics. It is deemed that these tasks are of importance in teaching writing to the students in the law field.
THE ROLE OF INVESTMENT AGREEMENTS IN THE DEVELOPMENT OF THE DIGITAL ECONOMY AND THEIR IMPLEMENTATION AT THE DOMESTIC LEVEL
Authors:   Tashkent State University of Law, Inamdjanova Elnora
Published: February 2023

This article explores the issues of legal regulation of investment agreements in the digital economy in a period of enhanced technology development. Economic and political imperatives are combined with technological innovation to drive the growth of the digital economy, with growth rates particularly high in developing countries. The strategy for this growth should be private sector driven, government driven, and reviewed by civil society and academia. Over the past decades, one of the most remarkable developments in international investment law has been the extraordinary increase in the number of agreements concluded regarding the protection or liberalization of foreign investment, where the investment regimes provided by States and the position of foreign investors play a special role. However, the foundations for these actions are missing with the definitions, concepts, and indicators of the digital economy, which is currently in quite a mess. The main purpose of the article is to reveal the essence of the digital economy, bilateral investment agreements, investment activities, crypto assets, as well as issues of improving the understanding of tokens and cryptocurrencies, including them in agreements from the point of view of the prospects for the development of the digital economy in accordance with the new adopted regulatory legal acts of the Republic of Uzbekistan.
ISSUES OF INFLUENCE OF RELATIONS OF THE BRANCHES OF POWER FOR THE FORM OF STATE GOVERNMENT
Authors:   Tashkent State University of Law, Turdiev Khayitjon
Published: February 2023

This article provides a comprehensive analysis of the role of public administration in the effective implementation of the principle of separation of powers. The problem of rational balance between parliament and government in the system of state power is relevant today. The relationship between the legislature and the executive is an important tool that directly affects the form of governance of each state. According to the author, the control and interaction of the branches of government without acting as an observer is important in the implementation of the state mechanism, but in the process, the branches of government must exercise their powers independently. The author also divides modern models of these relations into the following types depending on the principle of separation of powers and the principle of mutual balance and restraint: presidential, parliamentary and mixed. Analyzing the best practices of foreign countries and the approaches of legal scholars to the form of governance, given the specifics of the form of governance of the Republic of Uzbekistan in terms of functions, tasks and powers of the branches of government and the level of responsibility and mutual control.
IMPROVEMENT OF CUSTOMS PROCEDURES
Authors:   Customs Institute under SCC of the Republic of Uzbekistan, Khabibov Rustam
Published: February 2023

The article analyzes the time and content of customs clearance of cargo vehicles by inspectors of customs posts. The study found that inspectors are forced to carry out procedures not provided for in the Customs Code, but imposed by other regulations, such as charging for the operation of roads in transit, fees for tinted windows, or fines for traffic violations. The legislation establishes the maximum time for crossing the border by transport, and the object of customs control is clearly defined, these are goods, customs payments, and offenses. But sometimes, less time is spent on the main work than additional. When the issue of congestion of the customs post is raised, the emphasis is on simplifying customs procedures, and the redistribution of unusual functions is omitted from the list of proposals. The price of the problem considered in the framework of this article is equivalent to the image of the customs, and the efforts of our country to liberalize international trade.
CONSTITUTIONAL CULTURE – GUARANTEE OF EFFECTIVE ENFORCEMENT OF LEGISLATIVE ACTS
Authors:   Tashkent State University of Law, Odilqoriev Khojimurod
Published: February 2023

The article analyzes the role of the Constitution in the implementation of reforms provided for in the country’s development strategy, as well as the importance of constitutional culture in a clear and strict implementation of legislation, in strengthening executive discipline in government bodies, reveals the theoretical and practical aspects of its essence and content. The formation of a positive constitutional culture in our country is reflected, on the one hand, in the activities of law enforcement agencies, officials, and social structures, as well as in the mechanisms of protection of the Constitution and laws, the executive discipline of officials and individuals. It is important that each employee performs his or her duties conscientiously, qualitatively and responsibly. Therefore, strict requirements and evaluation criteria are being strengthened to implement modern management methods, improve the forms of control and increase the personal responsibility of heads of government agencies to ensure the implementation of the assigned tasks. Our large-scale reforms, carried out in strict accordance with the Constitution, will be an important basis for strengthening national statehood and sovereignty, ensuring an environment of stability and law and order, the rule of law, human rights and freedoms, interethnic harmony and religious tolerance.
REFUSAL TO INITIATE CRIMINAL PROCEEDINGS: PROBLEMS OF THEORY AND PRACTICE
Authors:   Tashkent State University of Law, Khudaybergenov Baxram
Published: February 2023

This article discusses the current problems of criminal procedure law concerning the institution of refusal to initiate criminal proceedings. This institution is of no small importance in the system of criminal procedure law, since the further fate of the received statement or message about the crimes being prepared or committed depends on it a lot. For the purpose of a detailed analysis of this institute, the author has studied the normative-legal, as well as internal acts aimed at regulating law enforcement practice. Based on the scientific research available to date regarding the institution of refusal to initiate criminal proceedings, the author conducts a comparative analysis of the criterion of justified and lawful refusal to initiate criminal proceedings. Having examined the procedural procedure for refusing to initiate a criminal case, the author emphasizes the need to indicate in the resolution the grounds for making such a decision provided for by the norms of the Criminal Procedure Code, references to the paragraph, part, article of the Criminal Procedure Law providing for responsibility for the crime, the signs of which served as the basis for the audit. Violation of this requirement may deprive this resolution of legal force. The correct decision to refuse to initiate a criminal case can serve as a guarantee against illegal and unjustified criminal prosecution.
CASE MANAGEMENT IN THE ELECTRONIC CIVIL CASE SYSTEM(E-COURTS)
Authors:   Tashkent State University of Law, Pirmatov Otabek
Published: February 2023

This article discusses the application of the Court Case Management System in the conduct of civil proceedings, and issues such processes as the reception of civil court documents, the distribution of court cases, the preparation for trial, the consideration of court cases, the adoption of court decisions, the direction and archiving of court documents in the Court Case Management System are also covered. Electronic Court Case Management System is described as a system for conducting electronic court cases, managing them through an automation system, as well as an electronic transmission, processing, and storage of documents, including court documents. In general, the article states that the Electronic Court Case Management System allows you to register court documents, edit court documents, fill them in by the parties, delete unnecessary documents, and easily find court documents in civil cases, in general, electronic preparation of a civil case in an electronic form. This article also describes how the Electronic Court Case Management System works in the judicial system of developed countries of the world and its advantages.
PROBLEMS OF LEGAL REGULATION OF CIRCUMSTANCES EXCLUDING PROCEEDINGS IN THE CASE
Authors:   University of Public Security of the Republic of Uzbekistan, Ataniyazov Jasurbek
Published: February 2023

In this article, the problems of legal regulation of circumstances excluding proceedings are investigated from a practical point of view. The article also examines the degree of conformity of decisions taken in practice based on the results of a pre-investigation check to refuse to monitor a criminal case with the grounds for terminating a criminal case without resolving the issue of guilt of Article 84 of the Criminal Procedure Code of the Republic of Uzbekistan, as well as conflicting circumstances that arise. The author expresses the opinion that the rehabilitated grounds in the Criminal Procedure case should be reflected in a separate chapter, and these grounds should be established in the norm of circumstances precluding the proceedings. The article also examines the content and advantages of grounds for refusal and termination of criminal cases, which is reflected in the Criminal Procedure legislation of foreign states. The study used such methods as analysis, synthesis, induction, deduction, comparative legal analysis. In the research work, advanced foreign experience, scientific and theoretical views, and investigative and judicial practice were studied, as a result of which proposals and recommendations have been developed for making appropriate amendments and additions to the Criminal Procedure Code of the Republic of Uzbekistan.
CONCEPT AND ESSENCE OF INDUSTRIAL PROPERTY RIGHT
Authors:   Tashkent State University of Law, Mekhmonov Kambariddin
Published: February 2023

The article analyzes the civil law regime of industrial property objects. The proposed study gives a complete picture of the objects of industrial rights, the content of the legal regime, trends in the development of relations related to objects of industrial property. In recent years, the trend of creating intellectual property in Uzbekistan and issuing documents of legal protection (patents) shows the lack of legal protection for the right holder. At the same time, the conditions for the patentability of industrial property objects, and the complexity of the conditions for issuing a title of protection make it difficult to implement legal protection. In exercising their rights, right holders inefficiently use the opportunities to protect not only national legislation but also international legal norms. An analysis of the legal regime of industrial property objects shows that these objects in Uzbekistan can be adequately protected by the use of specific legal measures and mechanisms. For the legislative settlement of these issues, it is necessary to bring the legislation of Uzbekistan in the field of intellectual property in line with international requirements and ensure the protection of the right to objects of industrial property. The author firmly adheres to the position that the main direction in the search for a legal solution to these issues should be the use of information technology and artificial intelligence. But it is too early to recognize the legal personality of artificial intelligence. The article also explores the scientific views of scientists, the strategy of the legislation of the Republic of Uzbekistan in the period of innovative development, and the settlement of disputes over inventions. In conclusion, the author draws certain conclusions.
CERTAIN ASPECTS OF THE DEPRIVATION AND RESTRICTION OF PARENTAL RIGHTS AS A MEASURE OF LEGAL INFLUENCE
Authors:   Higher School of Judges under the Supreme  Judicial Council of the Republic of Uzbekistan, Khayitov Muzaffar
Published: February 2023

Maintaining a reasonable ratio of parental and child relationships in the family environment is one of the important tasks of each society. The development of a child as a perfect person is inextricably linked with a healthy atmosphere in the family, as well as the correct relationship between parents and children. In this regard, the fulfilment of parental obligations in relation to the child, established by Family Law, plays an important role. Nevertheless, in society, due to the unhealthy environment in some families, parental obligations are not fulfilled to the proper extent, and the norms of the law on the relationship between parent and child are not observed. This entails certain measures of responsibility in the field of family law. For this reason, this socially negative situation that exists in society is studied by scientists and specialists as an object of research. The article considers the deprivation of parental rights, its restriction and its grounds as a measure of family legal influence. The grounds for deprivation of parental rights are based on the fact that the parent or one of them has committed an unlawful act or inaction. At the same time, it was emphasized that the deprivation of parental rights, and its restriction is at the same time a measure to defend and protect the child from the negative impact of the parent, and the family environment, to ensure the rights and legitimate interests of the child.
PROSPECTS FOR INTRODUCING MODERN FORMS OF PUBLIC CONTROL
Authors:   Tashkent State University of Law, Jakhanov Shahrukh
Published: February 2023

The article analyzes the issues of introducing modern forms of public control, including the opinions of various scientists about public control and the legal basis of public control. In addition, in the civil society that is being established in our country, state authorities and officials are under the control of the general public based on the Constitution and laws, and state agencies and officials are “hired servants” of civil society and are responsible to the people, in particular, the principles of communication with the people, the state to citizens that the principles of service provision are gaining importance in accelerating the processes of liberalization in all aspects of the society, ensuring public control over the activities of state power and management bodies in ensuring the implementation of laws, in a word, the establishment of sufficient public control is required today by the time itself and it is covered in this article. At the same time, in the conditions of the fundamental reforms taking place in our country, in order to further accelerate reforms in the direction of civil society and to ensure the rule of law, proposals were made to amend and add to the legislation directly related to public control.
Direct observations of NOx emissions over the San Joaquin Valley using airborne flux measurements during RECAP-CA 2021 field campaign
Authors: Zhu Qindan , Place Bryan , Pfannerstill Eva Y. , Tong Sha , Zhang Huanxin , Wang Jun , Nussbaumer Clara M. , Wooldridge Paul , Schulze Benjamin C. , Arata Caleb , Bucholtz Anthony , Seinfeld John H. , Goldstein Allen H. , Cohen Ronald C.
Published: February 2023

Abstract. Nitrogen oxides (NOx) are principle components of air pollution and serve as important ozone precursors. As the San Joaquin Valley (SJV) experiences some of the worst air quality in the United States, reducing NOx emissions is a pressing need, yet quantifying current emissions is complicated due to a mixture of mobile and agriculture sources. We performed airborne eddy covariance flux measurements during the Re-Evaluating the Chemistry of Air Pollutants in CAlifornia (RECAP-CA) field campaign in June 2021. Combining footprint calculations and land cover statistics, we disaggregate the observed fluxes into component fluxes characterized by three different land cover types. On average we find emissions of 2.95 mg m-2 h-1 over highways, 1.24 mg m-2 h-1 over urban areas and 0.79 mg m-2 h-1 over croplands. The calculated NOx emissions using flux observations are utilized to evaluate anthropogenic emission inventories and soil NOx emission schemes. We show that two anthropogenic inventories for mobile sources, EMFAC (EMssion FACtor) and FIVE (Fuel-based Inventory for Vehicle Emissions), yield similar agreement with emissions derived from measured fluxes over urban regions with 24 % and 22 % low bias, respectively. Three soil NOx schemes, including MEGAN v3 (Model of Emissions of Gases and Aerosols from Nature), BEIS v3.14 (Biogenic Emission Inventory System) and BDISNP (Berkeley Dalhousie Iowa Soil NO Parameterization), show substantial underestimates over the study domain. Compared to the cultivated soil NOx emissions derived from measured fluxes, MEGAN and BEIS are lower by more than one order of magnitude and BDISNP is lower by a factor of 2.7. Despite the low bias, observed soil NOx emissions and BDISNP present a similar spatial pattern as well as temperature dependence. We conclude that soil NOx is a key feature of the NOx emissions in the SJV and that a state-of-the-science model of these emissions is needed to simulate emissions for modeling air quality in the region.
Satellite remote sensing of regional and seasonal Arctic cooling showing a multi-decadal trend towards brighter and more liquid clouds
Authors: Lelli Luca , Vountas Marco , Khosravi Narges , Burrows John Philipp
Published: February 2023

Abstract. Two decades of measurements of spectral reflectance of solar radiation at
the top of the atmosphere and a complementary record of cloud properties
from satellite passive remote sensing have been analyzed for their
pan-Arctic, regional, and seasonal changes. The pan-Arctic loss of
brightness, which is explained by the retreat of sea ice during the current
warming period, is not compensated by a corresponding increase in cloud
cover. A systematic change in the thermodynamic phase of clouds has taken
place, shifting towards the liquid phase at the expense of the ice phase.
Without significantly changing the total cloud optical thickness or the
mass of condensed water in the atmosphere, liquid water content has
increased, resulting in positive trends in liquid cloud optical thickness
and albedo. This leads to a cooling trend by clouds being superimposed on
top of the pan-Arctic amplified warming, induced by the anthropogenic
release of greenhouse gases, the ice–albedo feedback, and related effects.
Except over the permanent and parts of the marginal sea ice zone around the
Arctic Circle, the rate of surface cooling by clouds has increased, both in
spring (−32 % in total radiative forcing for the whole Arctic) and in
summer (−14 %). The magnitude of this effect depends on both the
underlying surface type and changes in the regional Arctic climate.
Quantitative chemical assay of nanogram-level particulate matter using aerosol mass spectrometry: characterization of particles collected from uncrewed atmospheric measurement platforms
Authors: Niedek Christopher R. , Mei Fan , Zawadowicz Maria A. , Zhu Zihua , Schmid Beat , Zhang Qi
Published: February 2023

Abstract. Aerosol generation techniques have expanded the utility of aerosol
mass spectrometry (AMS) for offline chemical analysis of airborne particles
and droplets. However, standard aerosolization techniques require relatively large liquid volumes (e.g., several milliliters) and high sample masses that limit their utility. Here we report the development and characterization of a micronebulization AMS (MN-AMS) technique that requires as low as 10 µL of sample and can provide the quantification of the nanogram level of organic and inorganic substances via the usage of an isotopically labeled internal standard (34SO42-). Using standard solutions, the detection limits for this technique were determined at 0.19, 0.75, and 2.2 ng for sulfate, nitrate, and organics, respectively. The analytical recoveries for these species are 104 %, 87 %, and 94 %, respectively. This MN-AMS technique was applied successfully to analyze filter and impactor samples collected using miniature particulate matter (PM) samplers deployable on uncrewed atmospheric measurement platforms, such as uncrewed aerial systems (UASs) and tethered balloon systems (TBSs). Chemical composition of PM
samples collected from a UAS field campaign conducted at the Department of Energy's (DOE) Southern Great Plains (SGP) observatory was characterized. The offline MN-AMS data compared well with the in situ PM composition measured by a co-located aerosol chemical speciation monitor (ACSM). In addition, the MN-AMS and ion chromatography (IC) agreed well for measurements of sulfate and nitrate concentrations in the PM extracts. This study demonstrates the utility of combining MN-AMS with uncrewed measurement platforms to provide quantitative measurements of ambient PM composition.
Concentrations of dissolved dimethyl sulfide (DMS), methanethiol and other trace gases in context of microbial communities from the temperate Atlantic to the Arctic Ocean
Authors: Gros Valérie , Bonsang Bernard , Sarda-Estève Roland , Nikolopoulos Anna , Metfies Katja , Wietz Matthias , Peeken Ilka
Published: February 2023

Abstract. Dimethyl sulfide (DMS) plays an important role in the atmosphere by influencing the formation of aerosols and cloud condensation nuclei. In
contrast, the role of methanethiol (MeSH) for the budget and flux of reduced sulfur remains poorly understood. In the present study, we
quantified DMS and MeSH together with the trace gases carbon monoxide (CO), isoprene, acetone, acetaldehyde and acetonitrile in
North Atlantic and Arctic Ocean surface waters, covering a transect from 57.2 to 80.9∘ N in high spatial resolution in May–June
2015. Whereas isoprene, acetone, acetaldehyde and acetonitrile concentrations decreased northwards, CO, DMS and MeSH retained
substantial concentrations at high latitudes, indicating specific sources in polar waters. DMS was the only compound with a higher average concentration in
polar (31.2 ± 9.3 nM) than in Atlantic waters (13.5 ± 2 nM), presumably due to DMS originating from sea ice. At
eight sea-ice stations north of 80∘ N, in the diatom-dominated marginal ice zone, DMS and chlorophyll a markedly correlated
(R2 = 0.93) between 0–50 m depth. In contrast to previous studies, MeSH and DMS did not co-vary, indicating decoupled
processes of production and conversion. The contribution of MeSH to the sulfur budget (represented by DMS + MeSH) was on
average 20 % (and up to 50 %) higher than previously observed in the Atlantic and Pacific oceans, suggesting MeSH as an important
source of sulfur possibly emitted to the atmosphere. The potential importance of MeSH was underlined by several correlations with bacterial
taxa, including typical phytoplankton associates from the Rhodobacteraceae and Flavobacteriaceae families. Furthermore, the
correlation of isoprene and chlorophyll a with Alcanivorax indicated a specific relationship with isoprene-producing
phytoplankton. Overall, the demonstrated latitudinal and vertical patterns contribute to understanding how concentrations of central marine trace
gases are linked with chemical and biological dynamics across oceanic waters.
Estimating summer sea ice extent in the Weddell Sea during the early nineteenth century
Authors: Love Eleanor , Bigg Grant R.
Published: February 2023

Abstract. Over the past three decades, discordant trends in sea ice extent have been observed between the Arctic and Antarctic regions. Arctic sea ice extent has been characterised by a rapid decline, whereas Antarctic sea ice extent, while highly variable inter-annually, has tended to increase. Climate models have so far failed to capture these trends. Coupled with the limited pre-1970 sea ice dataset, this poses a significant challenge to quantifying the mechanisms responsible for driving such trends. However, historical records from early Antarctic expeditions contain a wealth of information regarding the nature and concentration of sea ice. Such records have been under-utilised, and their analysis may enhance our understanding of recent Antarctic sea ice variability. For the purpose of this study, 9 records from 8 Antarctic expeditions have been examined. Summer sea ice positions recorded during 1820–1843 have been compared to satellite observations from 1987–2017, as well as historical data for the period 1897–1917. Through analysis of these three time series, estimations for summer sea ice extent in the Weddell Sea, during the early nineteenth century have been produced. The key findings of this study indicate a nineteenth century average core summer northernmost sea ice latitude in much of the Weddell Sea that was further north than during the modern era, with nineteenth century February having significantly more sea ice by all measures. However, late summer sea ice was most extensive in the early years of the twentieth century.
Influence of atmospheric rivers and associated weather systems on precipitation in the Arctic
Authors: Lauer Melanie , Rinke Annette , Gorodetskaya Irina , Sprenger Michael , Mech Mario , Crewell Susanne
Published: February 2023

Abstract. In this study, we analyse the contribution of Atmospheric Rivers (ARs), cyclones, and fronts to the total precipitation in the Arctic. We focus on two distinct periods of different weather conditions from two airborne campaigns: ACLOUD (May/June 2017) and AFLUX (March/April 2019). Both campaigns covered the northern North Atlantic sector, the area in the Arctic that is affected by the highest precipitation rates. Using ERA5 reanalysis, we identify pronounced regional anomalies with enhanced precipitation rates compared to the climatology during ACLOUD due to these weather systems, whereas during AFLUX enhanced precipitation rates occur over most of the area. We have established a new methodology, that allows us to analyse the contribution of ARs, cyclones, and fronts to precipitation rates based on ERA5 reanalysis and different detection algorithms. Here, we distinguish whether these systems occur co-located or separately. The contributions differ seasonally. During ACLOUD (early summer), the precipitation rates are mainly associated with AR- (40 %) and front-related (55 %) components, especially if they are connected, while cyclone-related components (22 %) play a minor role. However, during AFLUX (early spring) the precipitation is mainly associated with cyclone-related components (62 %). For both seasons, snow is the dominant form of precipitation, and the small rain occurrence is almost all associated with ARs. About one-third of the precipitation can not be attributed to one of the weather systems, the so-called residual. While the residual can be found more frequently as convective than as large-scale precipitation, the rare occasion of convective precipitation (roughly 20 %) can not completely explain the residual. The fraction of precipitation classified as residual is reduced significantly when a precipitation threshold is applied that is often used to eliminate "artificial" precipitation. However, a threshold of 0.1 mm h−1 reduces the total accumulated precipitation by a factor of two (ACLOUD) and three (AFLUX) especially affecting light precipitation over the Arctic Ocean. We also show the dependence of the results on the choice of the detection algorithm serving as a first estimate of the uncertainty. In the future, we aim to apply the methodology to the full ERA5 record to investigate whether the differences found between the campaign periods are typical for the different seasons in which they were performed and whether any trends in precipitation associated with these weather systems can be identified.
Coupled hydrological and hydrodynamic modelling application for climate change impact assessment in the Nemunas River watershed–Curonian Lagoon–south-eastern Baltic Sea continuum
Authors: Idzelytė Rasa , Čerkasova Natalja , Mėžinė Jovita , Dabulevičienė Toma , Razinkovas-Baziukas Artūras , Ertürk Ali , Umgiesser Georg
Published: February 2023

Abstract. We analyse the cumulative impacts of climate change in a complex basin-lagoon-sea system continuum, which covers the Nemunas River basin, Curonian Lagoon, and the south-eastern part of the Baltic Sea. A unique state-of-the-art coupled modelling system, consisting of hydrological and hydrodynamic models, has been developed and used for this purpose. Results of four regional downscaled models from the Rossby Centre high-resolution regional atmospheric climate model have been bias-corrected using in situ measurements, and were used as forcing to assess the changes that the continuum will undergo until the end of this century. Results show that the Curonian Lagoon will be subjected to higher river discharges that in turn increase the outgoing fluxes into the Baltic Sea. Through these higher fluxes, both the water residence time and saltwater intrusion event frequency will decrease. Most of these changes will be more pronounced in the northern part of the lagoon, which is more likely to be influenced by the variations in the Nemunas River discharge. The southern part of the lagoon will experience lesser changes. Water temperatures in the entire lagoon and the south-eastern Baltic Sea will steadily increase, and salinity values will decrease. However, the foreseen changes in physical characteristics are not of the scale suggesting significant shifts in the ecosystem functioning, but are expected to manifest in some quantitative alterations in the nutrient retention capacity. However, some ecosystem services such as ice fishing are expected to vanish completely due to the loss of ice cover.
Predictable Decadal Forcing of the North Atlantic Jet Stream by Sub-Polar North Atlantic Sea Surface Temperatures
Authors: Strommen Kristian , Woollings Tim , Davini Paolo , Ruggieri Paolo , Simpson Isla R.
Published: February 2023

Abstract. It has been demonstrated that decadal variations in the North Atlantic Oscillation (NAO) can be predicted by current forecast models. While Atlantic Multidecadal Variability (AMV) in sea surface temperatures (SSTs) has been hypothesised as the source of this skill, the validity of this hypothesis and the pathways involved remain unclear. We show, using reanalysis and data from two forecast models, that the decadal predictability of the NAO can be entirely accounted for by the predictability of decadal variations in the speed of the North Atlantic eddy-driven jet, with no predictability of decadal variations in the jet latitude. The sub-polar North Atlantic (SPNA) is identified as the only potential source of an SST-based signal across the models and reanalysis, and the predictability of the jet speed is shown to be consistent with a forcing from the SPNA visible already within a single season. The pathway is argued to be tropospheric in nature, with the SPNA-induced heating extending up to the mid-troposphere, which alters the meridional temperature gradient around the climatological jet position. The link between SSTs and heatfluxes, which mediates the predictability, is shown to be underestimated in the forecast models by approximately a factor of two, with potential implications for the `signal-to-noise paradox'. The relative roles of anthropogenic aerosol emissions and the AMOC at generating predictable SPNA variability are also discussed. The analysis is extensively supported by the novel use of a set of seasonal hindcasts spanning the 20th century and forced with prescribed SSTs.
Confinement width controls the morphology and braiding intensity of submarine braided channels: Insights from physical experiments
Authors: Huang Sam Y. J. , Lai Steven Y. J. , Limaye Ajay B. , Foreman Brady Z. , Paola Chris
Published: February 2023

Abstract. Submarine channels conveying sediment gravity flows are often topographically confined, but the effects of confinement width on channel morphodynamics is incompletely understood. We use physical experiments and a reduced-complexity model to investigate the effects of confinement width (B) and inflow-to-sediment discharge ratio (Qin/Qs) on the evolution of submarine braided channels. The results show that a larger confinement width results in increased active braiding intensity (BIA), and that BIA takes longer to stabilize (i.e., a longer critical time, tc). At a fixed confinement width, a higher Qin/Qs slightly decreases the BIA. Digital Elevation Models of Difference (DoD) of the experiments allow measurement of the morphological active width (Wa) of the submarine channels and the bulk morphological change (Vbulk) within an experiment, defined as the sum of total erosion and deposition. We find that Wa and Vbulk are proportional to B. We further confirm that BIA is proportional to both dimensionless sediment-stream power (ω**) and dimensionless stream power (ω*). These trends are consistent for submarine braided channels both with and without confinement width effects. Furthermore, we built a reduced-complexity model (RCM) that can simulate flow bifurcation and confluence of submarine braided channels. The simulated flow distribution provides reliable predictions of flow depth and sediment transport rate in the experiments. Using kernel density estimation (KDE) to forecast the probability and trends of cross-sectional flow distribution and corresponding BIA under extreme events, we find that skewness of the flow distribution decreases as discharge increases. The development of braided submarine channels, shown here to extend to conditions of topographic confinement, suggests that factors not modelled here (e.g., fine sediment) may be necessary to explain the abundance of single-thread submarine channels in nature.
The porosity effect on the mechanical properties of summer sea ice in the Arctic
Authors: Wang Qingkai , Liu Yubo , Lu Peng , Li Zhijun
Published: February 2023

Abstract. To investigate the mechanical properties of sea ice in the current summer Arctic, two ice blocks were lifted using ship crane during an Arctic expedition in the summer of 2021. Examination of ice crystal structure showed a granular ice layer at the top underlain by a columnar ice layer. Sea ice samples were then machined from the ice blocks for mechanical experiments performed in the laboratory. Three-point bending tests were conducted at ice temperatures of −12 to −3 ºC, and uniaxial compressive strength tests were conducted at ice temperatures of −8 to −3 ºC with a strain rate range of 10−6–10−2 s−1. The ice density and salinity of each sample were measured to determine brine and gas volume fraction as well as porosity. Results showed that sea ice flexural strength decreased with increasing porosity, but did not change with varying brine or gas volume fractions. A parameterization was proposed to relate sea ice flexural strength to porosity. The sea ice strain modulus was also independent on porosity and volume fractions of gas and brine. The uniaxial compressive strength decreased with increasing porosity at both ductile and brittle strain rate regimes. Furthermore, three-dimensional surfaces were obtained to depict the sea ice uniaxial compressive strength varying with porosity and strain rate, based on which the transition strain rate from ductile to brittle behaviors was determined. It was found that the transition strain rate decreased with increasing porosity. Comparisons with previous studies on sea ice strength showed that the previously reported equations for sea ice flexural strength and strain modulus did not agree with the measured data. Compared with the strength calculated using early reported sea ice porosity, the flexural strength and uniaxial compressive strength of summer Arctic sea ice decreased in recent decades, which probably brings positive feedback to the Arctic navigation.
Brief communication: A clarification of wake recovery mechanisms
Authors: van der Laan Maarten Paul , Baungaard Mads , Kelly Mark
Published: February 2023

Abstract. Understanding wind turbine wake recovery is important for developing models of wind turbine interaction employed in the design of energy-efficient wind farm layouts. Wake recovery is often assumed or explained to be a shear-driven process; however, this is generally not accurate. In this work we show that wind turbine wakes recover mainly due to the divergence (lateral and vertical gradients) of Reynolds shear stresses, which transport momentum from the freestream towards the wake center. The wake recovery mechanisms are illustrated using a simple analytic model and results of large-eddy simulation.