Incongruities in recently revised radiofrequency exposure guidelines and standards.

The currently promulgated RF exposure guidelines and standards cover the entire range of RF radiation and apply predominantly to restrict RF-induced short-term heating and in guarding against raising tissue temperatures, including the 5G frequencies. There are substantial abnormalities in these putative health safety protection guidelines and standards. Some of the safety limits are irrelevant, debatable, and absent of scientific justification from the standpoint of safety and public health protection. Also, the cellular mobile 5G technology is hailed as a speedier and more secure wireless communication technology than its predecessor systems. The key supporting architecture uses millimeter-wave (mm-wave) and antenna array technology to achieve better directivity, lower latency, and elevated data transmission rates. For radiation protection, it is not obvious whether the health effects of 5G mm-wave radiations would be analogous or not to radiations from previous generations (which was classified as possibly carcinogenic in humans by IARC). The interaction of mm-waves with the structure and function of pertinent cellular elements and cutaneous neuroreceptors in the skin are of special concern. The current scientific database is inadequate at mm wavelengths to render a trustworthy appraisal or to reach a judgment with confidence.

Psychiatric correlates of alcohol and tobacco use disorders in U.S. adults aged 65 years and older: results from the 2001-2002 National Epidemiologic Survey of Alcohol and Related Conditions.

OBJECTIVE: To examine associations of alcohol and tobacco use disorders and psychiatric conditions among older U.S. adults. METHODS: Sample was individuals aged at least 65 years (N = 8,205) who participated in the 2001-2002 National Epidemiologic Survey on Alcohol and Related Conditions. Measurements included lifetime and past 12-month Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition alcohol use disorders (AUDs), tobacco use disorders (TUDs), and psychiatric conditions. RESULTS: Among older adults, prevalence of lifetime and past 12-month AUDs were 16.1% and 1.5% and lifetime and past 12-month TUDs were 8.7% and 4.0%, respectively. Lifetime TUD was associated with increased odds of both lifetime (odds ratio [OR]: 4.17; 95% confidence interval [CI]: 3.30-5.26) and past 12-month (OR: 2.52; 95% CI: 1.50-4.24) AUDs, and lifetime AUD was associated with increased odds of both lifetime (OR: 4.13; 95% CI: 3.28-5.210 and past 12-month (OR: 3.51; 95% CI: 2.47-4.96) TUDs. Any lifetime mood, anxiety, or personality disorder among older adults was associated with increased odds of lifetime AUD and TUD, any lifetime mood disorder was associated with increased odds of past 12-month AUD and TUD, and any personality disorder was associated with past 12-month TUD. CONCLUSION: There is a strong association between AUD and TUD among older U.S. adults as well as associations between AUD and TUD with mood, anxiety, and personality disorders. Understanding the psychiatric conditions associated with AUDs and TUDs, especially past 12-month use disorders involving alcohol or tobacco, will enable healthcare providers to target screening and be more aware of symptoms and signs of potential AUDs and TUDs among those at higher risk.

Carcinogenesis from chronic exposure to radio-frequency radiation.

The past two decades have seen exponential growth in demand for wireless access that has been projected to continue for years to come. Meeting the demand would necessarily bring about greater human exposure to microwave and radiofrequency (RF) radiation. Our knowledge regarding its health effects has increased. Nevertheless, they have become a focal point of current interest and concern. The cellphone and allied wireless communication technologies have demonstrated their direct benefit to people in modern society. However, as for their impact on the radiation health and safety of humans who are unnecessarily subjected to various levels of RF exposure over prolonged durations or even over their lifetime, the jury is still out. Furthermore, there are consistent indications from epidemiological studies and animal investigations that RF exposure is probably carcinogenic to humans. The principle of ALARA-as low as reasonably achievable-ought to be adopted as a strategy for RF health and safety protection.

Alcohol, tobacco, and nonmedical drug use disorders in U.S. Adults aged 65 years and older: data from the 2001-2002 National Epidemiologic Survey of Alcohol and Related Conditions.

OBJECTIVES: To examine the prevalence, sociodemographic, and health-related correlates of substance use disorders, including alcohol, tobacco, and nonmedical drug use among adults aged 65 years and older. DESIGN: The 2001-2002 National Epidemiologic Survey on Alcohol and Related Conditions, a cross-sectional survey of a population-based sample. SETTING: The United States. PARTICIPANTS: Eight thousand two hundred five adults aged 65 years and older. MEASUREMENTS: Prevalence of lifetime and past 12-month Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, determined alcohol, tobacco, and nonmedical drug use disorders. RESULTS: Prevalence of any substance use disorder was 21.1% during the lifetime and 5.4% in the past 12 months. Lifetime and past 12-month alcohol use disorders were 16.1% and 1.5%; tobacco use disorders were 8.7% and 4.0%; and nonmedical drug use disorders were 0.6% and 0.2%, respectively. Younger age was associated with greater odds of any lifetime or past 12-month substance use disorders. Men and those who were divorced or separated had greater odds of both lifetime alcohol and tobacco use disorders. Very good or excellent self-rated health was associated with lower odds of lifetime and past 12-month tobacco use disorders. Younger age and being divorced or separated were associated with greater odds of lifetime nonmedical drug use disorder. CONCLUSIONS: More than one in five older adults ever had a substance use disorder, and more than 1 in 20 had a disorder in the past 12 months, primarily involving alcohol or tobacco. Older adults have increased comorbidities and use of medications, which can increase risks associated with substance use.

Microwave thermoacoustic tomographic (MTT) imaging.

Microwave thermoacoustic tomography (MTT) uses microwave pulse-induced thermoelastic pressure waves to form planar or tomographic images. Since the generation and detection of thermoelastic pressure waves depends on dielectric permittivity, specific heat, thermal expansion, and acoustic properties of tissue, microwave thermoacoustic imaging possesses the characteristic features of a dual-modality imaging system. The unique attributes of the high contrast offered by microwave absorption and the fine spatial resolution furnished by ultrasound are being explored to provide a nonionizing and noninvasive imaging modality for characterization of tissues, especially for early detection of breast cancer. This paper reviews the research being conducted in developing MTT imaging for medical diagnosis. It discusses the science of thermoelastic wave generation and propagation in biological tissues, the design of prototype MTT systems, the reconstruction of tomographic images, and the application and accomplishment of prototype MTT systems in phantom models and experimental subjects.

Do health educator telephone calls reduce at-risk drinking among older adults in primary care?

BACKGROUND: Alcohol screening and brief intervention for unhealthy alcohol use has not been consistently delivered in primary care as part of preventive healthcare. OBJECTIVE: To explore whether telephone-based intervention delivered by a health educator is efficacious in reducing at-risk drinking among older adults in primary care settings. DESIGN: Secondary analyses of data from a randomized controlled trial. PARTICIPANTS: Subjects randomized to the intervention arm of the trial (n = 310). INTERVENTIONS: Personalized risk reports, advice from physicians, booklet about alcohol and aging, and up to three telephone calls from a health educator. All interventions were completed before the three-month follow-up. MEASUREMENTS: Risk outcomes (at-risk or not at-risk) at 3 and 12 months after enrollment. MAIN RESULTS: In univariate analyses, compared to those who remained at risk, those who achieved not at-risk outcome at 3 months were more likely to be women, Hispanic or non-white, have lower levels of education, consume less alcohol, drink less frequently, and have lower baseline number of risks. In mixed-effects logistic regression models, completing all three health educator calls increased the odds of achieving not at-risk outcome compared to not completing any calls at 3 months (OR 5.31; 95% CI 1.92-14.7; p = 0.001), but not at 12 months (OR 2.01; 95% CI 0.71-5.67; p = 0.18). CONCLUSIONS: Telephone-based intervention delivered by a health educator was moderately efficacious in reducing at-risk drinking at 3 months after enrollment among older adults receiving a multi-faceted intervention in primary care settings; however, the effect was not sustained at 12 months.

Importance of Exposure Duration and Metrics on Correlation Between RF Energy Absorption and Temperature Increase in a Human Model.

OBJECTIVE: This study investigated the influence of absorption metrics and averaging schemes on correlation between RF/microwave energy and induced temperature elevation for plane wave exposures. METHODS: A voxel-based, anatomically realistic model of the human body was considered. Correlation of electromagnetic fields and temperature increases were evaluated at several frequencies. Both specific absorption rate (SAR) and volume absorption rate (VAR) were considered. RESULTS: The best correlation with temperature increase occurs for exposure durations between 1 and 2 min both for SAR and VAR for most of the 700 to 2700 MHz frequencies considered. In this case, a 1 g mass or 1 cm3 volume appears to be optimal. However, for VAR, as frequency increases to above 900 MHz, a better correlation is achieved at slightly increased exposure times and volumes. For longer exposures, the maximum correlation coefficient is reduced, and the correlation favors larger averaging mass or volume. At steady-state (30 min), correlation of temperature increase with SAR is maximum for a mass of 9 g for all frequencies considered, whereas the volume for VAR maximum correlation is 15 cm3 for higher frequencies and 20 cm3 for lower frequencies. CONCLUSIONS: In general, SAR provides a better correlation with temperature compared to VAR for short exposures, while VAR renders better correlations for higher frequencies and longer exposures. SIGNIFICANCE: The correlation between electromagnetic absorption and temperature increases has implications in guidelines for limiting human exposure to electromagnetic fields and in biomedical applications such as imaging, sensing, and hyperthermia.

Dosimetric comparison between different quantities for limiting exposure in the RF band: rationale and implications for guidelines.

While source type and its distance from the subject are influential parameters, the fundamental exposure metrics are the physically measurable quantities of currents, external electric field and magnetic field strengths, and incident power density (when appropriate), which induce electric and magnetic fields that bring about the interaction of radiofrequency (RF) electromagnetic energy with biological systems. Induced fields are the primary cause for biological effect of RF exposure, regardless of the mechanism. Thus, in order to achieve a quantitative understanding of biological response, the induced electric field and the derived dosimetric quantities of specific absorption rate (SAR) and current density must be quantified and correlated with the observed phenomenon. In the established exposure guidelines, reference levels expressed in terms of physical quantities are introduced for practical exposure assessment purposes since the basic restrictions are often specified as dosimetric quantities that may be impractical to measure. The dosimetric quantity SAR, current density, and their determinations are tissue-type dependent and require a region of specific tissue mass for averaging. Thus, a smaller averaging region is scientifically more relevant and precise. It is emphasized that the sensitivity and resolution of present-day computational resources and experimental measurement techniques can provide accurate SAR values with a spatial resolution on the order of a 1 mm, in dimensions. Furthermore, most exposure guidelines are promulgated on a 4 W kg SAR to prevent any whole-body exposure from raising the body temperature to 1 degrees C above the norm at 37 degrees C. Special guidance may be needed for higher ambient temperature and humidity variations.

Hearing of microwave pulses by humans and animals: effects, mechanism, and thresholds.

The hearing of microwave pulses is a unique exception to the airborne or bone-conducted sound energy normally encountered in human auditory perception. The hearing apparatus commonly responds to airborne or bone-conducted acoustic or sound pressure waves in the audible frequency range. But the hearing of microwave pulses involves electromagnetic waves whose frequency ranges from hundreds of MHz to tens of GHz. Since electromagnetic waves (e.g., light) are seen but not heard, the report of auditory perception of microwave pulses was at once astonishing and intriguing. Moreover, it stood in sharp contrast to the responses associated with continuous-wave microwave radiation. Experimental and theoretical studies have shown that the microwave auditory phenomenon does not arise from an interaction of microwave pulses directly with the auditory nerves or neurons along the auditory neurophysiological pathways of the central nervous system. Instead, the microwave pulse, upon absorption by soft tissues in the head, launches a thermoelastic wave of acoustic pressure that travels by bone conduction to the inner ear. There, it activates the cochlear receptors via the same process involved for normal hearing. Aside from tissue heating, microwave auditory effect is the most widely accepted biological effect of microwave radiation with a known mechanism of interaction: the thermoelastic theory. The phenomenon, mechanism, power requirement, pressure amplitude, and auditory thresholds of microwave hearing are discussed in this paper. A specific emphasis is placed on human exposures to wireless communication fields and magnetic resonance imaging (MRI) coils.

A comparative evaluation of current orthodontic miniscrew systems.

Miniscrew placement has achieved widespread acceptance in orthodontic practice. However, selecting a suitable miniscrew system from among the available brands is not easy. The aim of this article is to help the clinician better understand the features of miniscrew systems currently available on the market and provide a useful guideline for their clinical use. The authors find that the ideal miniscrew design should include biocompatibility, bone-density-guided insertion, immediate loading, and compatibility with modern orthodontic accessories for 3-dimensional orthodontic control.

Enhancement of beta-catenin in cardiomyocytes suppresses survival protein expression but promotes apoptosis and fibrosis.

BACKGROUND: Beta-catenin has been implicated in cell-cell communication in a wide variety of developmental and physiological processes. Defective Wnt signaling could result in various cardiac and vascular abnormalities. Little is known regarding Wnt/frizzled pathway in cardiomyocyte apoptosis. METHODS: In this study, the role of b-catenin in apoptosis was investigated in H9c2 cardiomyocytes and primary cardiomyocytes isolated in diabetic Wistar rats. The cardiomyocytes were transfected with porcine cytomegalovirus (pCMV)-b-catenin plasmid in order to overexpress b-catenin. RESULTS: The transcription factor displayed a significant nuclear localization in Wistar rats with cardiac hypertension. Transfection of b-catenin plasmid induced apoptosis and reduced expression of survival pathway markers in cardiomyocytes in a dose-dependent manner. Furthermore, expression of fibrosis protein markers was upregulated by the overexpression. CONCLUSIONS: Taken together, these results revealed that altered Wnt/b-catenin signaling might provoke heart failure. (Cardiol J 2017; 24, 2: 195-205).