90 research outputs found

    Attitudes toward Conservation of the Transboundary Bialowieza Forest among Ecotourism Businesses in Poland and Belarus

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    The Bialowieza Forest is a contested transboundary forest massif in Poland and Belarus. Reflecting on transitions from value chains built on sustained yield forestry to ecotourism, we pioneer documentation of how country-specific legacies shape preferences toward increased forest protection at the expense of wood production. For both countries, we used a quantitative ordered logit model based on questionnaires to Polish and Belarusian ecotourism business owners to, for the first time, empirically study drivers of their preferences toward different Bialowieza Forest values, and we used qualitative data to identify attitudes toward the expansion of protected areas in the Bialowieza Forest. Whilst Belarusian ecotourism business owners supported increased area protection, the opposite was true for their Polish counterparts. The proportion of foreign guests co-varied with support toward increased area protection. Conversely, local origin, size of hospitality business, and role of foresters as customers decreased interest in area protection. The qualitative data revealed that narratives against extended area protection were spread in Poland but not in Belarus. The conflict over the conservation of the Polish part of the Bialowieza Forest involves actors and stakeholders with competing interests. A solution is that this remnant massif of the once widespread European temperate lowland forest becomes subject to a regional planning and zoning perspective. Encouraging multiple value chains and evidence-based collaborative learning are key components

    The role of vitamin D in the human body and the influence of vitamin D on the proliferation of cancer cells

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    The publication focuses on the presentation of the role of vitamin D3 in the human body. The content contains important information on the influence of vitamin D3 on the course of Covid-19 disease caused by the Sars-Cov-19 virus. Cholecalciferol has been studied for years. Its basic functions include the regulation of bone mineral metabolism and calcium-phosphorus metabolism. In addition, the publication characterizes the course of vitamin D3 synthesis and presents the important role of vitamin D3 in the body. Additionally, the currently conducted research in terms of anti-cancer properties of selected vitamin D3 analogues was described

    A Systematic Analysis of the Juniper Dual EC Incident

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    In December 2015, Juniper Networks announced that unknown attackers had added unauthorized code to ScreenOS, the operating system for their NetScreen VPN routers. This code created two vulnerabilities: an authentication bypass that enabled remote administrative access, and a second vulnerability that allowed passive decryption of VPN traffic. Reverse engineering of ScreenOS binaries revealed that the first of these vulnerabilities was a conventional back door in the SSH password checker. The second is far more intriguing: a change to the Q parameter used by the Dual EC pseudorandom number generator. It is widely known that Dual EC has the unfortunate property that an attacker with the ability to choose Q can, from a small sample of the generator\u27s output, predict all future outputs. In a 2013 public statement, Juniper noted the use of Dual EC but claimed that ScreenOS included countermeasures that neutralized this form of attack. In this work, we report the results of a thorough independent analysis of the ScreenOS randomness subsystem, as well as its interaction with the IKE VPN key establishment protocol. Due to apparent flaws in the code, Juniper\u27s countermeasures against a Dual EC attack are never executed. Moreover, by comparing sequential versions of ScreenOS, we identify a cluster of additional changes that were introduced concurrently with the inclusion of Dual EC in a single 2008 release. Taken as a whole, these changes render the ScreenOS system vulnerable to passive exploitation by an attacker who selects Q. We demonstrate this by installing our own parameters, and showing that it is possible to passively decrypt a single IKE handshake and its associated VPN traffic in isolation without observing any other network traffic

    On the matter of synovial fluid lubrication: implications for Metal-on-Metal hip tribology

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    Artificial articular joints present an interesting, and difficult, tribological problem. These bearing contacts undergo complex transient loading and multi axes kinematic cycles, over extremely long periods of time (>10 years). Despite extensive research, wear of the bearing surfaces, particularly metal–metal hips, remains a major problem. Comparatively little is known about the prevailing lubrication mechanism in artificial joints which is a serious gap in our knowledge as this determines film formation and hence wear. In this paper we review the accepted lubrication models for artificial hips and present a new concept to explain film formation with synovial fluid. This model, recently proposed by the authors, suggests that interfacial film formation is determined by rheological changes local to the contact and is driven by aggregation of synovial fluid proteins. The implications of this new mechanism for the tribological performance of new implant designs and the effect of patient synovial fluid properties are discussed

    Tribofilms on CoCrMo alloys: Understanding the role of the lubricant

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    The tribological activation of a passive metal alloy in an aqueous biological environment have been highlighted by many researchers; better known as bio-tribocorrosion. Tribocorrosion processes, which can be found at a number of metal-based biomedical implant interfaces, can be affected by lubricant species such as proteins, amino acids and salts. To date, researchers have quantified how the presence of organic species and the environment affect the tribological and corrosion process. However, the nature of the bio-films is still broadly to be explored. This study aims to understand how the lubricant - surface interactions influence the evolving frictional, corrosion and material volume loss from CoCrMo alloys and how the formation of any tribo-film at the interface may influence the aforementioned processes. This current research uses reciprocating tribocorrosion tests of CoCrMo surfaces in saline, protein, and protein-free cell culture medium lubricants (0.9% NaCl, 25% Foetal Bovine Serum (FBS) diluted in Phosphate Buffered Saline (PBS), Dulbecco's Modified Eagle Medium (DMEM) and 25% FBS in DMEM solutions). Results show the addition of organic constituents give a better tribology and corrosion performances. XPS confirmed that chemical reactions happened on the tested surfaces. Calcium, phosphorus and sulphur are shown to be catalysed to react in tribology-induced processes and have important roles in tribocorrosion. These results contribute to the understanding of protein-metal interactions occurring in tribofilm formation on wearing surfaces

    Cross-Talk between the Cellular Redox State and the Circadian System in Neurospora

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    The circadian system is composed of a number of feedback loops, and multiple feedback loops in the form of oscillators help to maintain stable rhythms. The filamentous fungus Neurospora crassa exhibits a circadian rhythm during asexual spore formation (conidiation banding) and has a major feedback loop that includes the FREQUENCY (FRQ)/WHITE COLLAR (WC) -1 and -2 oscillator (FWO). A mutation in superoxide dismutase (sod)-1, an antioxidant gene, causes a robust and stable circadian rhythm compared with that of wild-type (Wt). However, the mechanisms underlying the functions of reactive oxygen species (ROS) remain unknown. Here, we show that cellular ROS concentrations change in a circadian manner (ROS oscillation), and the amplitudes of ROS oscillation increase with each cycle and then become steady (ROS homeostasis). The ROS oscillation and homeostasis are produced by the ROS-destroying catalases (CATs) and ROS-generating NADPH oxidase (NOX). cat-1 is also induced by illumination, and it reduces ROS levels. Although ROS oscillation persists in the absence of frq, wc-1 or wc-2, its homeostasis is altered. Furthermore, genetic and biochemical evidence reveals that ROS concentration regulates the transcriptional function of WCC and a higher ROS concentration enhances conidiation banding. These findings suggest that the circadian system engages in cross-talk with the cellular redox state via ROS-regulatory factors

    Supporting Preservice Science Teachers' Ability to Attend and Respond to Student Thinking by Design

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    A teacher's ability to attend and respond to student thinking is a key instructional capacity for promoting complex and deeper learning in science classrooms. This qualitative multiple case study examines 14 preservice science teachers' (PSTs) responses to learning opportunities created to develop this capacity, as provided by a teacher preparation program. The PSTs engaged in multiple cycles of designing assessments and analyzing student work in coordination with clinical experiences in the field. Drawing upon the notions of responsiveness and noticing, we analyze teaching episodes for whether and how the PSTs in this study attended and responded to student thinking in instructional contexts. Several teaching episodes provide evidence of PSTs' productive responsiveness-suggesting modification in specific elements of instructional design to create better conditions for advancing students' scientific thinking. In general, however, the episodes suggest uneven success in PSTs' responses to student thinking. The findings point to two considerations in designing learning opportunities to enhance PSTs' responsiveness: (a) the use of high-quality assessment tasks that make student thinking visible and (b) helping PSTs to reframe the problems by deprivatizing PSTs' interpretations of student responses
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