Electrically-Small Low Q Radiator Structure and Method of Producing EM Waves Therewith

An electrically small radiator structure for radiating electromagnetic waves having an electrical size, k*a, with a value less than π/2 and above π/20,000 and configured to have at least a first and second magnetic, or electric, dipole element. Dipole elements are preferably oriented such that a source-associated standing energy value for the structure, or Wds(tR), is low, Radiative Q value preferably less than ⅓(k*a)3; and each of the elements, whether paired with respective electric dipole elements, is in electrical communication through a feed circuit to at least one power source. Further, a first dipole pair (or element) oriented orthogonally with respect to a second pair (or element) are in voltage phase-quadrature; the structure is operational at a frequency below 5 GHz; and dipole moments oriented such that the following is generally satisfied: a divergence of the Poynting vector of the pairs with respect to retarded time, namely ∇|t R ·N, has a value less than 1.0. Also, a method of producing electromagnetic waves using an electrically small radiator structure, including configuring the structure to have at least a first and second pair of dipole moments and an electrical size, k*a, with a value less than π/2 and above π/20,000; and powering a first feed area of the first pair and a second feed area of the second pair with at least one source operating at a frequency to radiate the waves

Reversible properties of polycrystalline ferromagnets--I , : Theory of the expected variation of the reversible properties with magnetization

Using a statistical model, equations are developed for the variation of the reversible susceptibility both parallel with and normal to the biasing magnetization as a function of the magnetization assuming that the susceptibility arises by domain rotation. The results are contrasted with previous results based upon domain-wall motion. It is concluded that the theory points out a new technique for the separation of the origins of the susceptibility. Equations are also given for the expected variation of the differential magnetostriction with magnetization both parallel with and normal to the field and for both domain-wall motion and domain rotationQuantitative results depend upon the fraction of the moments oriented in each direction. A function describing this distribution is discussed.An expression is given for the susceptibility matrix arising from domain rotation as a function of magnetization.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/32507/1/0000597.pd

Effect of V2O5 on Nickel‐Zinc Ferrite Formation

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/70856/2/JCPSA6-23-11-2205-1.pd

Low-temperature heat capacities and thermodynamic properties of zinc ferrites--II : Effect of thermal history and metallic additives

The heat capacities of annealed and quenched samples of Li0.005Zn0.90Fe2.05O4, and of quenched ZnFe2O4 have been determined over the range 5-350[delta]K. Addition of lithium to zinc ferrite lowers the temperature of the co-operative thermal anomaly associated with antiferromagnetic ordering transition in accord with theory, and quenching of either material results in nearly complete disappearance of the [lambda]-anomaly but modifies the pronounced high-temperature tail less significantly. The effects on the thermal properties are interpreted in terms of sublattice populations.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/32485/1/0000571.pd

Low temperature heat capacity and thermodynamic properties of zinc ferrite

The heat capacity of zinc ferrite (ZnFe2O4) has been determined over the range 5 to 350[deg]K. Molal values of Cp,S0, and H0-H00 computed from the thermal data are 32.99+/-0.03 cal/deg., 36[middle dot]01 +/-0[middle dot]03 cal/deg., and 18[middle dot]00+/-0[middle dot]02 cal, respectively, at 298.15[deg]K. A co-operative thermal anomaly associated with antiferromagnetic ordering occurs at 9.5[deg] and extends toward higher temperatures probably as a consequence of persisting short range order.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/32505/1/0000595.pd

The dust SED of dwarf galaxies

Context. High-resolution data from Spitzer, Herschel, and Planck allow us to probe the entire spectral energy distribution (SED) of morphologically separated components of the dust emission from nearby galaxies and allow a more detailed comparison between data and models. Aims. We wish to establish the physical origin of dust heating and emission based on radiation transfer models, that self-consistently connect the emission components from diffuse dust and the dust in massive star forming regions. Methods. NGC 4214 is a nearby dwarf galaxy with a large set of ancillary data, ranging from the ultraviolet (UV) to radio, including maps from Spitzer and Herschel and detections from Planck. We mapped this galaxy with MAMBO at 1.2mm at the IRAM 30m telescope. We extracted separate dust emission components for the HII regions (plus their associated PDRs on pc scales) and for the diffuse dust (on kpc scales). We analysed the full UV to FIR/submm SED of the galaxy using a radiation transfer model that self-consistently treats the dust emission from diffuse and star forming (SF) complexes components, considering the illumination of diffuse dust both by the distributed stellar populations and by escaping light from the HII regions. While maintaining consistency within the framework of this model, we additionally used a model that provides a detailed description of the dust emission from the HII regions and their surrounding PDRs on pc scales. Thanks to the large amount of available data and many previous studies for NGC 4214, very few free parameters remained in the model fitting process. Results. We achieve a satisfactory fit for the emission from HII + PDR regions on pc scales, with the exception of the emission at 8 μm, which is underpredicted by the model. For the diffuse emission we achieve a good fit if we assume that about 40-65% of the emission escaping the HII + PDR regions is able to leave the galaxy without passing through a diffuse ISM, which is not an unlikely scenario for a dwarf galaxy that has recently undergone a nuclear starburst. We determine a dust-to-gas mass ratio of 350-470, which is close to the expected value based on the metallicity. © 2012 ESO

Brain structural and functional asymmetry in human situs inversus totalis

Magnetic resonance imaging was used to investigate brain structural and functional asymmetries in 15 participants with complete visceral reversal (situs inversus totalis, SIT). Language-related brain structural and functional lateralization of SIT participants, including peri-Sylvian gray and white matter asymmetries and hemispheric language dominance, was similar to those of 15 control participants individually matched for sex, age, education, and handedness. In contrast, the SIT cohort showed reversal of the brain (Yakovlevian) torque (occipital petalia and occipital bending) compared to the control group. Secondary findings suggested different asymmetry patterns between SIT participants with (n = 6) or without (n = 9) primary ciliary dyskinesia (PCD, also known as Kartagener syndrome) although the small sample sizes warrant cautious interpretation. In particular, reversed brain torque was mainly due to the subgroup with PCD-unrelated SIT and this group also included 55% left handers, a ratio close to a random allocation of handedness. We conclude that complete visceral reversal has no effect on the lateralization of brain structural and functional asymmetries associated with language, but seems to reverse the typical direction of the brain torque in particular in participants that have SIT unrelated to PCD. The observed differences in asymmetry patterns of SIT groups with and without PCD seem to suggest that symmetry breaking of visceral laterality, brain torque, and language dominance rely on different mechanisms

Common, low-frequency, rare, and ultra-rare coding variants contribute to COVID-19 severity

The combined impact of common and rare exonic variants in COVID-19 host genetics is currently insufficiently understood. Here, common and rare variants from whole-exome sequencing data of about 4000 SARS-CoV-2-positive individuals were used to define an interpretable machine-learning model for predicting COVID-19 severity. First, variants were converted into separate sets of Boolean features, depending on the absence or the presence of variants in each gene. An ensemble of LASSO logistic regression models was used to identify the most informative Boolean features with respect to the genetic bases of severity. The Boolean features selected by these logistic models were combined into an Integrated PolyGenic Score that offers a synthetic and interpretable index for describing the contribution of host genetics in COVID-19 severity, as demonstrated through testing in several independent cohorts. Selected features belong to ultra-rare, rare, low-frequency, and common variants, including those in linkage disequilibrium with known GWAS loci. Noteworthily, around one quarter of the selected genes are sex-specific. Pathway analysis of the selected genes associated with COVID-19 severity reflected the multi-organ nature of the disease. The proposed model might provide useful information for developing diagnostics and therapeutics, while also being able to guide bedside disease management. © 2021, The Author(s)