557 research outputs found

    ICANN—Now and Then: ICANN’s Reform and Its Problems

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    This paper sheds some light upon the major problem arising from the current normative infrastructure of the DNS and provides a possible solution to the current physical problem of the DNS. The paper\u27s main focus is the single-entity control of the A Root. The paper uses as a starting point the Blueprint prepared by the Committee on ICANN Evolution and Reform and raises the question: Has this reform done anything to resolve the single-entity control of the A Root? The paper argues that the reform has done nothing to solve the problem because the international privatization of the DNS merely substitutes the administration of the DNS function without making changes to the normative infrastructure of the DNS. In light of the above, the paper argues that there is a need to declare independence from a one-entity controlled DNS. The suggested approach is to share authority over the root by acknowledging that countries that are accountable to their populations are the authorities for their own ccTLDs. Once technical and political independence has been achieved, the technical and, to some degree, political management of the DNS should be exercised through an international body. In order to initiate a discussion for a truly international body this paper offers nine principles that a new international ccTLD cooperation organization should observe when working on its own creation

    The Patriation of .ca

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    Country code top level domains (‘‘ccTLD’’s), such as .ca, are distinct from generic top-level domains (‘‘gTLD’’s), such as .com, in that they are generally conceived to be associated with a specific country. In Canada, the authority to operate the technical functions of the .ca domain name registry has been delegated to the Canadian Internet Registration Authority (‘‘CIRA’’) by a United States non-profit corporation, the Internet Corporation for Assigned Names and Numbers (‘‘ICANN’’). The authority to make policy regarding the .ca has purportedly been delegated to CIRA by the Government of Canada. There is an issue, however, as to whether ICANN’s delegation of authority to CIRA to manage the technical functions of the .ca reflects a diminished ability of Canada to decide the identity of the .ca registry and, by implication, to control the registry’s operational policies, thereby diminishing Canada’s sovereignty over the .ca domain. While ICANN has been criticized as illegitimate, unfair, anticompetitive and its dispute settlement procedure systematically biased, this paper steps back from those issues and asks whether acknowledging the technical authority of a private foreign entity over the .ca domain is consistent with Canada’s commitment to political sovereignty. For, as Lessig has pointed out, in cyberspace, code (computer hardware and software) is like law in that code regulates how cyberspace behaves. Applying this observation to the DNS, we argue that the structure of the DNS, which enables the U.S. Department of Commerce (‘‘DoC’’) to decide who manages the technical aspects of the .ca, implies that Canada lacks sovereign control over the .ca domain space and related policies and laws

    SOVEREIGN DOMAINS: A Declaration of Independence of ccTLDs from Foreign Control

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    In the year 2000, the Government Advisory Committee (“GAC”) of the Internet Corporation for Assigned Names and Numbers (“ICANN”) passed a set of principles that essentially claimed national sovereignty over country code top-level domains (“ccTLD”s) such as .us, .ca, .uk and .au. Shortly thereafter, ICANN redelegated several ccTLDs in accordance with new GAC principles. Despite the outcry accompanying the passage of these principles and ICANN’s self-professed adherence thereto, the entire exercise could easily be criticized as merely symbolic because of the overriding power of ICANN in the operation of the Domain Name System (“DNS”). Indeed, Stuart Lynn, ICANN’s current president, summed up the lack of power that ccTLDs have within the governance structure of the Internet when he opined that “ICANN could, in theory, recommend that a particular ccTLD be redelegated to a cooperating administrator. If the United States government accepted that recommendation, non-cooperating ccTLD administrators would be replaced.

    On the Cryptographic Fragility of the Telegram Ecosystem

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    Telegram is a popular messenger with more than 550 million monthly active users and a large ecosystem of different clients. Telegram has its own bespoke transport layer security protocol, MTProto 2.0. This protocol was recently subjected to a detailed study by Albrecht et al. (IEEE S&P 2022). They gave attacks on the protocol and its implementations, along with a security proof for a modified version of the protocol. We complement that study by analysing a range of third-party client implementations of MTProto 2.0. We report practical replay attacks for the Pyrogram, Telethon and GramJS clients, and a more theoretical timing attack against the MadelineProto client. We show how vulnerable third-party clients can affect the security of the entire ecosystem, including official clients. Our analysis reveals that many third-party clients fail to securely implement MTProto 2.0. We discuss the reasons for these failures, focussing on complications in the design of MTProto 2.0 that lead developers to omit security-critical features or to implement the protocol in an insecure manner. We also discuss changes that could be made to MTProto 2.0 to remedy this situation. Overall, our work highlights the cryptographic fragility of the Telegram ecosystem

    ROXAS – an efficient and accurate tool to detect vessels in diffuse-porous species

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    Wood-anatomical parameters form a valuable archive to study past limitations on tree growth and act as a link between dendrochronology and ecophysiology. Yet, analysing these parameters is a time-consuming procedure and only few long chronologies exist. To increase measurement efficiency of wood-anatomical parameters, novel tools like the automated image-analysis system ROXAS were developed. So far, ROXAS has only been applied to measure large earlywood vessels in ring-porous species. In this study, we evaluate if ROXAS is also suitable for efficient and accurate detection and measurement of vessels in diffuse-porous European beech. To do so, we compared the outcome of ROXAS with that of the established measurement programme Image-Pro Plus in terms of efficiency and accuracy. The two methods differed substantially in efficiency with automatic measurements using ROXAS being 19 times faster than with Image-Pro Plus. Although the procedures led to similar patterns in annual variation of mean vessel area and vessel density, the absolute values differed. Image-Pro Plus measured systematically lower mean vessel areas and higher vessel densities than ROXAS. This was attributed to the species-specific technical settings in ROXAS, leading to more realistic results than those obtained using the default settings in Image-Pro Plus. A shortcoming of ROXAS was, however, that small vessels

    Endoscopic endodontic microsurgery: 2-year evaluation of healing and functionality.

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    This prospective clinical study aimed to evaluate the benefits of the endoscope as an aid to root-end management, and to assess the treatment outcome during 2 years following surgery. Forty-three endodontic surgical procedures in 30 patients were performed with the aid of an endoscope and followed for a period of 2 years. Radiographic criteria and clinical evaluation were used to assess the outcome. All cases were evaluated in terms of healing and functionality. 91.1% and 90.7% of the teeth evaluated after 1 and 2 years, respectively, were classified as successful. We found no statistically significant differences for both healing and functionality between the 1- and 2-year evaluations. No difference related to tooth type or tooth location was found at the 2-year follow-up. Fisher's exact test was used to statistically assess the difference between successful and unsuccessful cases for each of the variables considered. The endoscope can be an aid for endodontic surgical procedures in terms of both periapical healing and functionality up to 2 years follow-up

    The evolving therapeutic landscape of trastuzumab-drug conjugates: Future perspectives beyond HER2-positive breast cancer

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    A novel class of drugs, antibody-drug conjugates (ADCs), are now rapidly emerging as highly effective treatments for solid tumours. ADCs conjugate conventional chemotherapeutics with highly selective targeted monoclonal antibodies. Anti-HER2 therapies selectively target cancer cells expressing human epidermal growth factor receptor 2 (HER2), among them trastuzumab has been the first HER2-targeting monoclonal antibody to achieve successful results that made it the backbone of anti-HER2 therapies. Trastuzumab drug conjugates (T-DCs), use trastuzumab as a selective antibody to lead cytotoxic drugs inside cancer cells. Trastuzumab-emtansine (T-DM1) and trastuzumab-deruxtecan (T-Dxd) are the two approved T-DCs. T-Dxd along with other five T-DCs represents “second generation ADCs” that has been firstly tested in HER2 positive breast cancer (BC) and then in HER2-low BC and other cancers showing promising results thanks to extraordinary and innovative pharmacokinetic and pharmacodynamic characteristics. The evidence generated so far are establishing them as a completely new class of agents effective in solid cancer treatments but also warrants physicians against unconventional toxicity profiles. The role of T-DCs in HER2-positive BC has been largely reviewed, while in this review, we provided for the first time in literature an overview of trastuzumab drug conjugates (T-DCs) approved and/or in clinical development with a specific focus on their efficacy and safety profile in HER2-low BC and other solid tumours different from BC. We started by analysing T-DCs biological characteristics that underly the differences in T-DCs pharmacodynamics and safety profile, then presented the main evidence on the activity and efficacy of these emerging T-DCs in HER2-low BC and other HER2 overexpressing and/or mutated solid tumours and lastly, we provided an overview of the complex and still evolving scenario in which these compounds should be allocated. A specific focus on possible combination strategies with other drugs such as immunotherapy, chemotherapy and target therapy, to increase T-DCs activity and eventually overcome future upcoming resistance mechanisms, are here also critically reviewed

    The utility of bulk wood density for tree-ring research

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    Bulk wood density measurements are recognized for their utility in ecology, industry, and biomass estimations.. In tree-ring research, microdensitometric techniques are widely used, but their ability to determine the correct central tendency has been questioned. Though rarely used, it may be possible to use bulk wood density as a tool to check the accuracy of and even correct microdensitometric measurements. Since measuring bulk wood density in parallel with X-ray densitometry is quickly and easily done, we suspect that its omission is largely due to a lack of awareness of the procedure and/or its importance. In this study, we describe a simple protocol for measuring bulk wood density tailored for tree-ring researchers and demonstrate a few possible applications. To implement real-world examples of the applications, we used a sample of existing X-ray and Blue Intensity (BI) measurements from 127 living and dead Pinus sylvestris trees from northern Sweden to produce new measurements of bulk wood density. We can confirm that the central tendency in this sample material is offset using X-ray densitometry and that the diagnosis and correction of X-ray density is easily done using bulk wood density in linear transfer functions. However, this approach was not suitable for our BI measurements due to heavy discoloration. Nevertheless, we were able to use bulk wood density to diagnose and improve the use of deltaBI (latewood BI – earlywood BI) with regard to its overall trends and multi-centennial variability in a dendroclimatological application. Moreover, we experimented with percent of latewood width, scaled with bulk wood density, as a time- and cost-effective proxy for annual ring density. Although our reconstruction only explains about half of the variation in ring density, it is most likely superior to using fixed literature values of density in allometric equations aimed at biomass estimations. With this study, we hope to raise new awareness regarding the versatility and importance of bulk wood density for dendrochronology by demonstrating its simplicity, relevance, and applicability

    Regularization in quantum field theory from the causal point of view

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    The causal approach to perturbative quantum field theory is presented in detail, which goes back to a seminal work by Henri Epstein and Vladimir Jurko Glaser in 1973. Causal perturbation theory is a mathematically rigorous approach to renormalization theory, which makes it possible to put the theoretical setup of perturbative quantum field theory on a sound mathematical basis. Epstein and Glaser solved this problem for a special class of distributions, the time-ordered products, that fulfill a causality condition, which itself is a basic requirement in axiomatic quantum field theory. In their original work, Epstein and Glaser studied only theories involving scalar particles. In this review, the extension of the method to theories with higher spin, including gravity, is presented. Furthermore, specific examples are presented in order to highlight the technical differences between the causal method and other regularization methods, like, e.g. dimensional regularization.Comment: 75 pages, 8 figures, style file included, some comments and references adde

    Machine learning outperforms clinical experts in classification of hip fractures

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    Hip fractures are a major cause of morbidity and mortality in the elderly, and incur high health and social care costs. Given projected population ageing, the number of incident hip fractures is predicted to increase globally. As fracture classification strongly determines the chosen surgical treatment, differences in fracture classification influence patient outcomes and treatment costs. We aimed to create a machine learning method for identifying and classifying hip fractures, and to compare its performance to experienced human observers. We used 3659 hip radiographs, classified by at least two expert clinicians. The machine learning method was able to classify hip fractures with 19% greater accuracy than humans, achieving overall accuracy of 92%
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