IoT malware is rapidly increasing due to variants easily generated from publicly available source codes. Malware image classification capable of fast and accurate malware identification attracts attention. Since the classification by imaging is affected by malware binary changes, a binary modification without behavioral changes can be a potential attacking method to the classification by imaging. There are concerns that by combining the publicly available malware source code with readily available source code obfuscation tools, it is possible to construct an effective attack that bypasses image classifiers relatively simply. In this study, we show the effectiveness of the attack by source code obfuscation and the possibility of defense against the attack. The contribution of this research is twofold. 1) We showed that Obfuscator-LLVM (oLLVM) code obfuscation could be used as an attack method on malware image classification. The obfuscated malware binaries made by oLLVM were misclassified by VGG16-based image classifier for all the attacked malware families including Mirai, Lightaidra, and Bashlite. 2) We showed that classifier training with obfuscated samples could address this attack method. We confirmed that the malware image classifier trained with obfuscated malware binaries made by oLLVM could classify with an accuracy of 100% the malware family with obfuscation as the obfuscated original malware family.

Hyperammonemia is often experienced as a complication of liver cirrhosis, but it is not well known that hyperammonemic encephalopathy is induced by urease-splitting bacteria in the urinary tract. We report two cases of hyperammonemia in two women in their 80s with liver cirrhosis. Both cases were treated as hepatic encephalopathy with usual treatment, but there was no improvement. Urinalysis showed marked alkalinuria and urine culture showed urease-splitting bacteria, which were thought to be related to the pathology. After drainage of urine and administration of antimicrobials, the blood ammonia level decreased and the urine pH level normalized. The mechanism of this is that ammonia is produced by the degradation of urinary urea by urease-producing bacteria in the bladder, and in the presence of dysuria, it is absorbed into the blood circulation from the bladder venous plexus, leading to hyperammonemia.Urine findings should be confirmed when a patient with liver disease develops hyperammonemia or is unresponsive to conventional hepatic encephalopathy treatment.

In the searchable encryption, searching encrypted data is slow, compared to searching non-encrypted data. As a solution, there is an acceleration method that discloses a small portion of a hash value of keyword to be searched. The disclosure bit(s) allows the cloud to narrow down the search space and reduce the amount of computation. The more bits are disclosed, the faster the search speed becomes. However, repeated disclosure of part of hashed keyword in queries leads to reveal the frequency distribution of plaintext keywords. The longer the disclosure bits are, the more accurate revealed distribution becomes. In this paper, we propose a method to determine the disclosure bit length by using minimum entropy and k-anonymity. Furthermore, scalability of the proposed method is enhanced by employing distributed databases. To show that the proposed method achieves both high acceleration effect and security, we show an evaluation result of the proposed method applied to the conventional full-text search system using searchable encryption. Our evaluation result shows that the proposed method reduces the search time of the system by up to 97.2% when the number of stored document files is 1,000. While a database in this evaluation is designed so that disclosure bits satisfy at least 31-anonymity by using the proposed method, we observe that the database actually satisfies 2,598-anonymity.

Low-rate Distributed Denial of Service (LDDoS) attacks degrade the quality of TCP links with low average traffic by exploiting vulnerabilities in the TCP/IP protocol and routing queue management mechanisms. The ideal transmission rate of the attack pulse in the most classical RTO-based LDDoS attacks (aka: Shrew attacks) is greater than or equal to the bandwidth of the target bottleneck link, and it is assumed that the attacker is able to set a suitably large transmission rate. However, the attacker does not always know the bandwidth of the target bottleneck link in real-world attack scenarios. In this paper, we propose a strategy for executing a low-rate shrew DDoS attack against a bottleneck link of unknown bandwidth and buffer size under a scenario targeting a residential network. The proposed attack strategy degrades downstream traffic from a specific service to the target network to the desired quality while keeping the attack traffic stealthy by exploratively increasing the pulse rate while estimating the attack effect by building bot nodes in the residential network.

In thermal and nuclear power plants, 70% of the generated thermal energy is lost as waste heat. The temperature of the waste heat is below the boiling temperature of water. Here, we show a long-term heat-storage material that absorbs heat energy at warm temperatures from 38°C (311 K) to 67°C (340 K). This unique series of material is composed of scandium-substituted lambda-trititanium-pentoxide (λ-Sc x Ti3-x O5). λ-Sc x Ti3-x O5 not only accumulates heat energy from hot water but also could release the accumulated heat energy by the application of pressure. λ-Sc x Ti3-x O5 has the potential to accumulate heat energy of hot water generated in thermal and nuclear power plants and to recycle the accumulated heat energy on demand by applying external pressure. Furthermore, it may be used to recycle waste heat in industrial factories and automobiles.

Coronavirus disease 2019 (COVID-19) is associated with various symptoms and changes in hematological and biochemical variables. However, clinical features, which can differentiate COVID-19 from non-COVID-19, are not clear. We therefore examined the key clinical features of COVID-19 and non-COVID-19 patients. This study included 60 COVID-19 patients and 100 non-COVID-19 patients, diagnosed by PCR, and no significant differences in the age and sex were seen between the two groups. The frequencies of fatigue, loose stool, diarrhea, nasal obstruction, olfactory dysfunction, taste dysfunction, underlying hyperlipidemia, and the prescription of angiotensin II receptor blocker (ARB) were significantly higher in COVID-19 patients than those in non-COVID-19 patients. The counts of leucocytes, neutrophils, lymphocytes, eosinophils, monocytes, and basophils and the levels of chloride and calcium in blood of COVID-19 patients were significantly lower than those of non-COVID-19 patients. The frequencies of atypical lymphocytes and the levels of lactate dehydrogenase (LDH) and potassium were significantly higher in COVID-19 than those in non-COVID-19. The C-reactive protein (CRP) level in COVID-19 patients was significantly lower than that in non-COVID-19 patients, when we compared CRP levels among patients with elevated CRP. This study is the first to indicate that electrolyte levels and the frequency of atypical lymphocytes in COVID-19 are significantly different from those in non-COVID-19. Fatigue, loose stool, diarrhea, nasal obstruction, olfactory dysfunction, and taste dysfunction were the key symptoms of COVID-19. Furthermore, hyperlipidemia and ARB may be risk factors of COVID-19. In conclusion, leucocytes, leucocyte fractions, CRP, LDH, and electrolytes are useful indicators for COVID-19 diagnosis.

Objectives: Sicca syndrome is characterized by dry mouth and eyes and results in a reduction of the patient's quality of life. Various natural plants, including certain herbs, have long been employed to alleviate such symptoms. Rooibos grown in South Africa is one of the potent herbal plants used for the treating dry mouth. However, the precise mechanism of action by which rooibos alleviates symptoms of dryness remains unclear. Methods: The in vivo effects of rooibos extract (RE), which comprises eriodictyol-6-C-glucoside, on the secretory function of saliva and tears were analyzed after intraoral RE administration using wild-type C57BL/6 (B6) mice. In addition, the mechanisms of RE were investigated after administration of a muscarinic acetylcholine receptor 3 (M3R) antagonist. Results: Tear and saliva volumes in mice increased significantly and in a dose-dependent manner following intraoral RE administration compared to those in mice in the control group administered H2O. An experiment performed using darifenacin administration revealed that the effects of RE on secretory function were exerted via M3R. Conclusion: These results suggest that RE administration is an effective treatment for symptoms of dryness and may be used in clinical settings against sicca syndrome. (C) 2019 Published by Elsevier B.V. on behalf of Japanese Association for Oral Biology.

In Japan, early warnings such as the earthquake early warning and the tsunami warning are broadcast to cellular phones by using the Earthquake and Tsunami Warning System (ETWS) [1]. The connectivity of a LTE device (UE: user equipment) depends on the LTE base station (evolved Node B: eNB) which acts as a relay with the Internet. Therefore it is difficult to broadcast early warnings during large-scale disasters.

In recent years, with the increase in the frequency of use of smartphones,terminals require high security user authentication. In current personal authentication of smartphone, What you know and What you are are generally used. However, they have problems with memory load, operation load, and use of user-specific persistent data such as a fingerprint. In this paper, we propose a new personal authentication method to reduce memory load, operation load without using user-specific persistent data. As an approach of this method, we consider combining image based authentication with excellent storage load and operation load and behavior history based authentication using continuous information with change. The proposed method uses screen shot of the web page that the user most closely watched as correct image, and screen shots of web page not seen by user as incorrect images. We examined two methods, selection method excluding web pages of the same domain as correct image and selection method based on semantic distance with search keyword as selection methods for incorrect images. We also verified its effectiveness by comparing the two methods. As a result, it was shown that the incorrect image selection method based on the semantic distance to the search keyword is effective.

The power supply interruption and the destruction of communications infrastructure in the event of wide area disasters make it difficult to communicate urgent information such as disaster situation and safety information. DTN (Delay Tolerant Network), which is an infrastructure-less communication technique, is one of the solution methods. However DTN has a problem of power consumption in order to realize information communication in a wide area disaster. The evacuees are assumed to communicate with others by their own mobile terminals in the disaster-stricken areas. Since these terminals have limited electric power, it is preferable to use a communication method considering power usage efficiency. In this paper, we propose a disaster-time communication system using a message ferry method for exchanging and collecting disaster situation and safety information. Also, in order to improve the power usage efficiency of the network on the proposed system, we propose and evaluate a method to efficiently utilize electric power for communication by setting multistage threshold for power remaining.

In Japan, an Earthquake and Tsunami Warning System (ETWS) in LTE is being adopted to provide emergency warning for quick evacuation. This paper proposes to enhance the ETWS by leveraging the device to device (D2D) communications in LTE. In particular, we propose to extend the coverage of e node B (eNB)s through relaying among User Equipment (UE)s with Proximity Service (ProSe) device to device (D2D) capability, such that the important ETWS messages may reach people even out of the coverage area of eNBs. By exploiting the distribution information of UEs around the eNB, we also develop a new relaying scheme to reduce the number of transmissions in the relaying process, such that an efficient dissemination of ETWS messages can be achieved. The experiment results based on a network scenario with UE density of 24 UEsjkm2 or more indicate that by applying the proposed relaying scheme, the total number of transmissions can be reduced as high as 27% on average.

We previously discovered that rooibos extract activates the M3 muscarinic acetylcholine receptor (M3R), a key component of exocrine secretion. In this study, we examined the rooibos extract for active components in vitro and monitored its fast-acting effects against dryness in humans. Our in vitro analysis demonstrated that the M3R-stimulating effect of rooibos extract was similar to that of eriodictyol-6-C-β-d-glucoside (E6CG), whereas other rooibos constituents (aspalathin, orientin, isoorientin or eriodictyol-8-C-β-d-glucoside) were not active. In a placebo-controlled, double-blinded crossover clinical trial, 36 subjects with dryness at the mouth, eyes, and skin consumed a daily dose of either 100 mg rooibos or placebo tablets for three days. Rooibos extract ingestion increased resting-saliva content, tear volume, and stratum corneum moisture content, and reduced the dryness symptoms. In conclusion, rooibos extract contains E6CG as an M3R activator and stimulates exocrine gland secretion, which relieves dryness at the mouth, eyes, and skin in humans.

Recently, cyber attacks through Web sites such as Drive-by download attacks or phishing attacks are increasing rapidly. The attackers can illegally acquire personal information of users by these attacks and cause economical damages. We aim to detect malicious Web sites which cause economic damages. The analysis of the features of the network address part of the IP address revealed that the features of malicious IP address has time change. Therefore, reflecting the time changes of these features, we classified unknown malicious Web sites. As a result of the evaluation experiment, classification accuracy could be improved.

We have developed a SiC-FET-type gas sensor that enables highly sensitive NO detection in high-temperature exhaust gas. The gate of the FET is a gas detection layer consisting of yttria-stabilized zirconia, nickel oxide, and platinum, which are deposited on the SiC substrate. The threshold voltage of the FET depends on the NO concentration. Experimental results demonstrate that the FET-type sensor can detect NO concentration less than 1 ppm, thus meeting the specifications required to satisfy the strict regulations for exhaust gas in the next generation.

Recently, IPv6 wireless sensor networks are widely spread in various fields including IoT environments. However, on these sensor networks, it is difficult to use secure communication technologies that can become large overhead, due to power saving of the wireless nodes is important. As one approach to deal with this problem, a method of focusing on Nonce which is one element of security and separating it from secure communication is proposed. However, it remains a problem that not suit in environments such as wireless sensor networks where reliability of communication is not ensured. In this paper, we propose a Nonce truncation method that can deal with such environments. Our method transfer information of about several bits that can estimate the Nonce associated the ciphertext as the truncated Nonce value. We evaluated the effectiveness of our method by comparing the lifetime of the nodes between the method and previous methods.