National-Scale Assessment of Climate Change Impacts on Two Native Freshwater Fish Using a Habitat Suitability Model

Climate change, which has the potential to alter water flow and temperature in aquatic environments, can influence the freshwater fish habitat. This study used an ecological habitat suitability model (EHSM), which integrates hydraulic (water depth and velocity) and physiologic (water temperature) suitability, to investigate the impact of climate change on two native freshwater fish species (Zacco platypus and Nipponocypris koreanus) in South Korea. The model predicted that in 2080 (2076–2085), the decrease in average ecological habitat suitability (EHS) will be higher for N. koreanus (19.2%) than for Z. platypus (9.87%) under the representative concentration pathway (RCP) 8.5 scenario. Under the same condition, EHS for Z. platypus and N. koreanus at 36.5% and 44.4% of 115 sites, respectively, were expected to degrade significantly (p Z. platypus and N. koreanus was much lower (7.8% and 10.4%, respectively) under the RCP 4.5 scenario, suggesting a preventive measure for carbon dioxide emission. Partial correlation analysis indicated that the number of hot days (i.e., days on which the temperature exceeds the heat stress threshold) is the variable most significantly (p < 0.05) related to EHS changes for both species. This study suggests that the EHSM incorporating the effect of water temperature on the growth and heat stress of fish can be a promising model for the assessment of climate change impacts on habitat suitability for freshwater fish

National-Scale Assessment of Climate Change Impacts on Two Native Freshwater Fish Using a Habitat Suitability Model

Climate change, which has the potential to alter water flow and temperature in aquatic environments, can influence the freshwater fish habitat. This study used an ecological habitat suitability model (EHSM), which integrates hydraulic (water depth and velocity) and physiologic (water temperature) suitability, to investigate the impact of climate change on two native freshwater fish species (Zacco platypus and Nipponocypris koreanus) in South Korea. The model predicted that in 2080 (2076&ndash;2085), the decrease in average ecological habitat suitability (EHS) will be higher for N. koreanus (19.2%) than for Z. platypus (9.87%) under the representative concentration pathway (RCP) 8.5 scenario. Under the same condition, EHS for Z. platypus and N. koreanus at 36.5% and 44.4% of 115 sites, respectively, were expected to degrade significantly (p &lt; 0.05). However, the habitat degradation for Z. platypus and N. koreanus was much lower (7.8% and 10.4%, respectively) under the RCP 4.5 scenario, suggesting a preventive measure for carbon dioxide emission. Partial correlation analysis indicated that the number of hot days (i.e., days on which the temperature exceeds the heat stress threshold) is the variable most significantly (p &lt; 0.05) related to EHS changes for both species. This study suggests that the EHSM incorporating the effect of water temperature on the growth and heat stress of fish can be a promising model for the assessment of climate change impacts on habitat suitability for freshwater fish

Architectural supports to protect OS kernels from code-injection attacks

The kernel code injection is a common behavior of kernel -compromising attacks where the attackers aim to gain their goals by manipulating an OS kernel. Several security mechanisms have been proposed to mitigate such threats, but they all suffer from non-negligible performance overhead. This paper introduces a hardware reference monitor, called Kargos, which can detect the kernel code injection attacks with nearly zero performance cost. Kargos monitors the behaviors of an OS kernel from outside the CPU through the standard bus interconnect and debug interface available with most major microprocessors. By watching the execution traces and memory access events in the monitored target system, Kargos uncovers attempts to execute malicious code with the kernel privilege. According to our experiments, Kargos detected all the kernel code injection attacks that we tested, yet just increasing the computational loads on the target CPU by less than 1% on average

Ambassy: A Runtime Framework to Delegate Trusted Applications in an ARM/FPGA Hybrid System

Many mobile systems run on ARM-based devices today. People use these for increasingly diverse yet security-sensitive applications. ARM has adopted a security model to tackle this threat, where they manage private information in an isolated trusted execution environment (TEE) provided by TrustZone. This TrustZone-based model has been proven effective, but due to security concerns, it is available solely for the vendors applications, thereby hindering the broad use of TrustZone. Consequently, we propose a runtime framework backed by TrustZone to construct a secondary TEE. AMBASSY has its residence built on an on-chip field-programmable gate array (FPGA), which is a standard component in an ARM/FPGA hybrid system readily available on the market today. This study, to the best of our knowledge, is the first attempt to broaden the use of TrustZone by using an FPGA to build a secondary TEE for arbitrary third-parties, which otherwise should be expelled to the Normal World. This paper describes many design challenges that we have overcome to fully implement AMBASSY on an FPGA. Our experiments demonstrate the practicality of AMBASSY by presenting the security analysis and performance results of third-party application samples. The samples all run safely on AMBASSY, with shorter execution time than regular TEE applications in TrustZone (by a factor of 5.552)

Architectural Supports to Protect OS Kernels from Code-Injection Attacks and Their Applications

The kernel code injection is a common behavior of kernel-compromising attacks where the attackers aim to gain their goals by manipulating an OS kernel. Several security mechanisms have been proposed to mitigate such threats, but they all suffer from non-negligible performance overhead. This article introduces a hardware reference monitor, called Kargos, which can detect the kernel code injection attacks with nearly zero performance cost. Kargos monitors the behaviors of an OS kernel from outside the CPU through the standard bus interconnect and debug interface available with most major microprocessors. By watching the execution traces and memory access events in the monitored target system, Kargos uncovers attempts to execute malicious code with the kernel privilege. On top of this, we also applied the architectural supports for Kargos to the detection of ROP attacks. KS-Stack is the hardware component that builds and maintains the shadow stacks using the existing supports to detect this ROP attacks. According to our experiments, Kargos detected all the kernel code injection attacks that we tested, yet just increasing the computational loads on the target CPU by less than 1% on average. The performance overhead of the KS-Stack was also less than 1%

Development of Dithieno[3,2-b:2′,3′-d]thiophene (DTT) Derivatives as Solution-Processable Small Molecular Semiconductors for Organic Thin Film Transistors

Novel solution-processable dithieno[3,2-d:2′,3′-d]thiophene (DTT) derivatives with alkylated thiophene or alkyl chain substituents, 2,6-bis(5-octylthiophen-2-yl)dithieno[3,2-b:2′,3′-d]thiophene (compound 1), 2,6-bis(5-(2-ethylhexyl)thiophen-2-yl)dithieno[3,2-b:2′,3′-d]thiophene (compound 2), and 2,6-dioctyldithieno[3,2-b:2′,3′-d]thiophene (compound 3), have been synthesized and employed as small molecular organic semiconductors for organic field-effect transistors (OFETs). All compounds exhibited good thermal stability over 290 °C, while different side groups of DTT compounds afforded different melting temperatures. The molecular orbital energy levels were experimentally and theoretically calculated, and their trend was almost the same. The developed compounds were employed as active layers for top-contact/bottom-gate OFETs with average charge carrier mobility as high as 0.10 cm2/Vs and current on/off ratio &gt; 107 in ambient atmosphere. Notably, DTT derivative with linear alkyl chain (-octyl) substituents showed the best device performance. High device performance could be attributed to the large grains and continuous surface coverages as well as high film texture of the corresponding semiconductor films

Artificial Compound Eye Systems and Their Application: A Review

The natural compound eye system has many outstanding properties, such as a more compact size, wider-angle view, better capacity to detect moving objects, and higher sensitivity to light intensity, compared to that of a single-aperture vision system. Thanks to the development of micro- and nano-fabrication techniques, many artificial compound eye imaging systems have been studied and fabricated to inherit fascinating optical features of the natural compound eye. This paper provides a review of artificial compound eye imaging systems. This review begins by introducing the principle of the natural compound eye, and then, the analysis of two types of artificial compound eye systems. We equally present the applications of the artificial compound eye imaging systems. Finally, we suggest our outlooks about the artificial compound eye imaging system

Silicon-micromachined Retinal Tracks: An Economical Tool for Artifical Retinal Implantation

This work is supported by the Nano Bioelectronics and System Research Center (BRC-NBS) of the Korea Science and Engineering Foundation at Seoul National University

Silicon Retinal Tack for the Epiretinal Fixation of the Polyimide Electrode Array

Silicon-micromachined retinal tacks were developed for the fixation of the epiretinal-type retina-stimulating microelectrode array. Silicon retinal tacks were fabricated by using the silicon on insulator (SOI) process, a method of releasing silicon structures in a SOI wafer. The dimensions of the retinal tack were substantially smaller than those of the conventional titanium tack, at 1.5 mm long, 150 lm wide, and 150 lm thick. To enhance the durability and biocompatibility of the retinal tack, 3 lm-thick parylene film was uniformly deposited on the entire surfaces. Short-term evaluation of the durability of the silicon retinal tack in vivo showed acceptable biocompatibility and firm fixation of the microelectrode array onto the retina.This paper was supported by the Nano Bioelectronics and Systems Research Center of Seoul National University, which is an ERC supported by the Korean Science and Engineering Foundation (KOSEF)