Electromagnetic field interactions with the human body: Observed effects and theories

The effects of nonionizing electromagnetic (EM) field interactions with the human body were reported and human related studies were collected. Nonionizing EM fields are linked to cancer in humans in three different ways: cause, means of detection, and effective treatment. Bad and benign effects are expected from nonionizing EM fields and much more knowledge is necessary to properly categorize and qualify EM field characteristics. It is concluded that knowledge of the boundary between categories, largely dependent on field intensity, is vital to proper future use of EM radiation for any purpose and the protection of the individual from hazard

Microwave Spectroscopy

Contains reports on one research project.Joint Services Electronics Program (Contract DAAB07-71-C-0300

A small-molecule catalyst of protein folding in vitro and in vivo

AbstractBackground: The formation of native disulfide bonds between cysteine residues often limits the rate and yield of protein folding. The enzyme protein disulfide isomerase (PDI) catalyzes the interchange of disulfide bonds in substrate proteins. The two -Cys-Gly-His-Cys- active sites of PDI provide a thiol that has a low pKa value and a disulfide bond of high reduction potential (E°').Results: A synthetic small-molecule dithiol, (±)-trans-1,2-bis(2-mercaptoacetamido)cyclohexane (BMC), has a pKa value of 8.3 and an E°' value of −0.24 V. These values are similar to those of the PDI active sites. BMC catalyzes the activation of scrambled ribonuclease A, an inactive enzyme with non-native disulfide bonds, and doubles the yield of active enzyme. A monothiol analog of BMC, N-methylmercaptoacetamide, is a less efficient catalyst than BMC. BMC in the growth medium of Saccharomyces cerevisiae cells increases by > threefold the heterologous secretion of Schizosaccharomyces pombe acid phosphatase, which has eight disulfide bonds. This effect is similar to that from the overproduction of PDI in the S. cerevisiae cells, indicating that BMC, like PDI, can catalyze protein folding in vivo.Conclusions: A small-molecule dithiol with a low thiol pKa value and high disulfide E°' value can mimic PDI by catalyzing the formation of native disulfide bonds in proteins, both in vitro and in vivo

Microwave Spectroscopy

Contains research objectives, summary of research and reports on two research projects.Joint Services Electronics Programs (U. S. Army, U. S. Navy, and U. S. Air Force) under Contract DAAB07-71-C-030

GGD 37: An Extreme Protostellar Outflow

We present the first Spitzer-IRS spectral maps of the Herbig-Haro flow GGD 37 detected in lines of [Ne III], [O IV], [Ar III], and [Ne v]. The detection of extended [O IV] (55 eV) and some extended emission in [Ne v] (97 eV) indicates a shock temperature in excess of 100,000 K, in agreement with X-ray observations, and a shock speed in excess of 200 km s(-1). The presence of an extended photoionization or collisional ionization region indicates that GGD 37 is a highly unusual protostellar outflow.Jet Propulsion Laboratory, under NASA 1407NASA 1257184Jet Propulsion Laboratory (JPL) 960803University of Rochester 31419-5714Astronom

Spatial distribution of Mercury’s flux ropes and reconnection fronts: MESSENGER observations

We perform a statistical study of flux ropes and reconnection fronts based on MErcury Surface, Space ENviroment, GEochemistry, and Ranging (MESSENGER) magnetic field and plasma observations to study the implications for the spatial distribution of reconnection sites in Mercury’s near magnetotail. The results show important differences of temporal and spatial distributions as compared to Earth. We have surveyed the plasma sheet crossings between −2 RM and −3 RM downtail from the planet, i.e., the location of Near‐Mercury Neutral Line (NMNL). Plasma sheets were defined to be regions with β ≥ 0.5. Using this definition, 39 flux ropes and 86 reconnection fronts were identified in the plasma sheet. At Mercury, the distributions of flux ropes and reconnection fronts show clear dawn‐dusk asymmetry with much higher occurrence rate on the dawnside plasma sheet than on the duskside. This suggests that magnetic reconnection in Mercury’s magnetotail occurs more frequently in the dawnside than in the duskside plasma sheet, which is different than the observations in Earth’s magnetotail showing more reconnection signatures in the duskside plasma sheet. The distribution of plasma sheet thickness shows that plasma sheet near the midnight is the thinnest part and does not show obvious asymmetry. Thus, the reasons that cause magnetic reconnection to preferentially occur on the dawnside of the magnetotail at Mercury may not be the plasma sheet thickness and require further study. The peak occurrence rates of flux ropes and reconnection fronts in Mercury’s plasma sheet are ~ 60 times higher than that of Earth’s values, which we interpret to be due to the highly variable magnetospheric conditions at Mercury. Such higher occurrence rate of magnetic reconnection would generate more plasma flows in the dawnside plasma sheet than in the duskside. These plasma flows would mostly brake and initiate the substorm dipolarization on the postmidnight sector at Mercury rather than the premidnight susbtorm onset location at Earth.Key PointsOccurrence rate of FRs and RFs at Mercury is ~ 60 times higher than at Earth, due to the variable magnetospheric conditions at MercuryMagnetic reconnection occurs more frequently in the dawnside than in the duskside in Mercury’s plasma sheet, opposite to Earth’s resultsPlasma flows would brake and initiate dipolarizations on the postmidnight sector at Mercury different to the premidnight locations at EarthPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/134095/1/jgra52821.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/134095/2/jgra52821_am.pd

Upstream Ultra‐Low Frequency Waves Observed by MESSENGER’s Magnetometer: Implications for Particle Acceleration at Mercury’s Bow Shock

We perform the first statistical analysis of the main properties of waves observed in the 0.05–0.41 Hz frequency range in the Hermean foreshock by the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) Magnetometer. Although we find similar polarization properties to the “30 s” waves observed at the Earth’s foreshock, the normalized wave amplitude (δB/|B0|∼0.2) and occurrence rate (∼0.5%) are much smaller. This could be associated with relatively lower backstreaming proton fluxes, the smaller foreshock size and/or less stable solar wind (SW) conditions around Mercury. Furthermore, we estimate that the speed of resonant backstreaming protons in the SW reference frame (likely source for these waves) ranges between 0.95 and 2.6 times the SW speed. The closeness between this range and what is observed at other planetary foreshocks suggests that similar acceleration processes are responsible for this energetic population and might be present in the shocks of exoplanets.Key PointsWe perform the first statistical analysis (4,536 events) of the main properties of the lowest‐frequency waves in the Hermean foreshockSmall normalized wave amplitude (0.2) and occurrence (0.5%) are likely due to low backstreaming proton flux and variable external conditionsThe normalized backstreaming protons speed (∼0.95–2.6) suggests similar acceleration processes occur at several planetary shocksPeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/155492/1/grl60476.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/155492/2/grl60476_am.pd

A Statistical Study of the Force Balance and Structure in the Flux Ropes in Mercury’s Magnetotail

This study presents a statistical investigation of the force balance and structures in the flux ropes in Mercury’s magnetotail plasma sheet by using the measurements of MErcury Surface, Space ENviroment, GEochemistry, and Ranging (MESSENGER). One hundred sixty-eight flux ropes were identified from the 14 hot seasons of MESSENGER from 11 March 2011 to 30 April 2015, and 143 of them show clear magnetic field enhancements with the core field being -20% higher than the background magnetic field. The investigation on the force balance of these 143 flux ropes shows that magnetic pressure gradient force cannot be solely balanced by magnetic tension force, implying that thermal plasma pressure gradient force cannot be neglected in the flux ropes. We employ a non-force-free model considering the contribution of thermal pressure to resolve the physical properties of flux ropes in Mercury’s magnetotail. Twenty-eight flux ropes are obtained through the fitting to the non-force-free model. The flux ropes are found to be consistent with the flattened structures, in which the mean semimajor is -851 km and semiminor is -333 km, both are several times the local proton inertial length. The average core field is estimated to be -57.5 nT, and flux content is -0.019 MWb, much larger than the previous results obtained from force-free flux rope model. The importance of thermal pressure gradient in the force balance of the flux ropes and the flattened structure indicates that the flux ropes in Mercury’s magnetotail plasma sheet are mostly in early stage of the evolution, and still contain enough plasma to affect their magnetic structures.Key PointsThermal pressure gradient is significant for the flux ropes in Mercury’s magnetotailNon-force-free modeling reveals the flatten structure and much higher magnetic flux of the flux ropes different from the previous studiesFlux ropes in this study should be in their early stage of evolution and could be strongly affected by thermal pressurePeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151305/1/jgra55044_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151305/2/jgra55044.pd

Efficient Implementation and the Product State Representation of Numbers

The relation between the requirement of efficient implementability and the product state representation of numbers is examined. Numbers are defined to be any model of the axioms of number theory or arithmetic. Efficient implementability (EI) means that the basic arithmetic operations are physically implementable and the space-time and thermodynamic resources needed to carry out the implementations are polynomial in the range of numbers considered. Different models of numbers are described to show the independence of both EI and the product state representation from the axioms. The relation between EI and the product state representation is examined. It is seen that the condition of a product state representation does not imply EI. Arguments used to refute the converse implication, EI implies a product state representation, seem reasonable; but they are not conclusive. Thus this implication remains an open question.Comment: Paragraph in page proof for Phys. Rev. A revise