Human Exposure to Radiofrequency Energy above 6 GHz: Review of Computational Dosimetry Studies

International guidelines/standards for human protection from electromagnetic fields have been revised recently, especially for frequencies above 6 GHz where new wireless communication systems have been deployed. Above this frequency a new physical quantity "absorbed/epithelia power density" has been adopted as a dose metric. Then, the permissible level of external field strength/power density is derived for practical assessment. In addition, a new physical quantity, fluence or absorbed energy density, is introduced for protection from brief pulses (especially for shorter than 10 sec). These limits were explicitly designed to avoid excessive increases in tissue temperature, based on electromagnetic and thermal modeling studies but supported by experimental data where available. This paper reviews the studies on the computational modeling/dosimetry which are related to the revision of the guidelines/standards. The comparisons with experimental data as well as an analytic solution are also been presented. Future research needs and additional comments on the revision will also be mentioned.Comment: 38 pages, 3 figure

State-free End-to-End Encrypted Storage and Chat Systems based on Searchable Encryption

Searchable symmetric encryption (SSE) has attracted significant attention because it can prevent data leakage from external devices, e.g., clouds. SSE appears to be effective to construct such a secure system; however, it is not trivial to construct such a system from SSE in practice because other parts must be designed, e.g., user login management, defining the keyword space, and sharing secret keys among multiple users who usually do not have public key certificates. In this paper, we describe the implementation of two systems based upon the state-free dynamic SSE (DSSE) (Watanabe et al., IEICE Transactions 2022), i.e., a secure storage system (for a single user) and a chat system (for multiple users). In addition to the DSSE protocol, we employ a secure multipath key exchange (SMKEX) protocol (Costea et al., CCS 2018), which is secure against some classes of unsynchronized active attackers. It allows the chat system users without certificates to share a secret key of the DSSE protocol in a secure manner. To realize end-to-end encryption, the shared key must be kept secret; thus, we must consider how to preserve the secret on, for example, a user\u27s local device. However, this requires additional security assumptions, e.g., tamper resistance, and it seems difficult to assume that all users have such devices. Thus, we propose a secure key agreement protocol by employing the SMKEX and login information (password) that does not require an additional tamper-resistant device. Combining the proposed key agreement protocol with the underlying state-free DSSE protocol allow users who know the password to use the systems from multiple devices. We also consider a kind of explainability of the system. That is, usually, general users are not aware of the underlying DSSE and thus such secure systems should be used without recognizing the underlying cryptographic tools. On the other hand, it is highly desirable to easily explain how to encrypt data, how to preserve encrypted data on external storages, and so on, even for general users. Thus, we also implement a concierge functionality that visualizes DSSE-related data processing

Development of icterus gravis in a preterm infant with G71R UGT1A1 polymorphism

BACKGROUND: Uridine diphosphate-glucuronosyltransferase (UGT) gene family is involved in the detoxification of biomaterials and drugs in the liver. Among the UGT gene family members, only UGT1A1 is involved in bilirubin conjugation. As a result, deficient UGT1A1 activity causes jaundice. One disease that is characterized by reduced UGT1A1 activity is Gilbert’s syndrome. Two prevalent UGT1A1 polymorphisms responsible for Gilbert’s syndrome have been identified: G71R in exon 1 and A(TA)7TAA in the TATA box of the promoter region. Recently, the G71R polymorphism has been associated with breastfeeding jaundice and neonatal hyperbilirubinemia in term infants. However, its association with jaundice in very low birth weight infants (VLBWIs) has never been reported. CASE PRESENTATION: The patient was a female born at 28 weeks, 4 days gestation with a birth weight of 1172 g. On day 21, intense yellowing of the skin and eyes was noted, and the patient’s total bilirubin level was 23.7 mg/dL (her direct bilirubin level was 2.1 mg/dL). Therefore, an exchange transfusion was conducted. She had neither blood type incompatibility nor a family history of constitutional jaundice. Metabolic screens for amino and organic acids were negative. No elevation of any of the examined antibody titers was noted, and no evidence of an inflammatory reaction was observed. In addition, no hematological abnormalities were detected. The direct/indirect Coombs test, irregular antibody test and red blood cell antibody dissociation test were all negative, and her thyroid function was normal. We performed sequence analysis of the UGT1A1 gene after the patient’s parents provided written informed consent. Exon 1 of the UGT1 gene on chromosome 2 was analyzed by direct sequencing. A heterozygous substitution from G to A (211G→A: G71R) in base 211 was noted. CONCLUSION: We speculated that this preterm infant with carrying the G71R polymorphism reduced UGT1A1 activity and developed severe jaundice that was likely triggered by factors such as breast feeding and medications. The polymorphism appears at some frequency among VLBWIs, which would necessitate adequate care of severe jaundice even after the acute phase

Orange Juice and Its Component, Hesperidin, Decrease the Expression of Multidrug Resistance-Associated Protein 2 in Rat Small Intestine and Liver

We investigated the effects of orange juice (OJ) or hesperidin, a component of OJ, on the pharmacokinetics of pravastatin (PRV) and the expression of both protein and mRNA of multidrug resistance-associated protein 2 (Mrp2) in the rat small intestine and liver. Eight-week-old male Sprague-Dawley rats were used in this study. OJ or a 0.079% hesperidin suspension was administered orally for 2 days. Tap water was given as a control. A single dose of PRV at 100 mg/kg p.o. was administered after 2 days of OJ, hesperidin, or tap water ingestion. The AUC, Cmax, and t1/2 values of PRV were significantly increased in OJ group. Mrp2 protein and mRNA levels in the small intestine and liver, respectively, were significantly decreased after the ingestion of OJ. The same results were obtained with hesperidin. These results suggest that the changes in PRV pharmacokinetic parameters and the decrease in Mrp2 expression caused by OJ are due to hesperidin in the juice

Influences of protein ingestion on glucagon-like peptide (GLP)-1-immunoreactive endocrine cells in the chicken ileum

Influences of a specific dietary nutrient on glucagon-like peptide (GLP)-1-containing cells in the chicken intestine are not yet clear. Significance of dietary protein level on GLP-1-containing cells in the chicken ileum was investigated. Chickens fed control or experimental diets of varying protein levels were examined using immunohistochemical and morphometrical techniques. We show that the protein ingestion had an impact on the activities of GLP-1-immunoreactive cells in the chicken ileum. Weight gains declined with decreasing dietary crude protein (CP) levels, but no significant differences were detected in the daily feed intake and villous height. GLP-1-immunoreactive cells with a round or oval shape were frequently observed in the lower CP level groups (4.5% and 0%). Frequencies of occurrence of GLP-1-immunoreactive cells were 41.1 +/- 4.1, 38.5 +/- 4, 34.8 +/- 3.1 and 34.3 +/- 3.7 (cells/mm(2), mean +/- SD) for dietary CP level of 18%, 9%, 4.5% and 0% groups, respectively and significant differences were recognized between the control and lower CP level groups (P<0.05). Multiple regression analysis indicated a significant correlation between the daily protein intake and frequencies of occurrence of GLP-1-immunoreactive cells. The protein ingestion is one of the signals that influence GLP-1-containing cells in the chicken small intestine.ArticleANIMAL SCIENCE JOURNAL. 85(5):581-587 (2014)journal articl