Paleomagnetic of ODP Hole 133-823A

Hole 823A covers the upper 120 m (Subunits IA and IB) of Site 823 at the bottom of the Queensland Trough. This hole contains an abundance of gravity-flow deposits, but is thought to have a monotonic age sequence. Above 32 mbsf, a strong, stable (normal) magnetic remanence having a relatively small viscous remanent magnetization (VRM) is seen. Below 32 mbsf, the sediments are subject to widespread VRM, which appears to obliterate the primary magnetization and precludes identification of the Brunhes/Matuyama boundary. Progressive alternating field (AF) demagnetization is limited to low fields (typically <400 Oe) by the weak magnetization in these sediments. As a consequence, the possibility of a high-coercivity component of primary magnetization cannot be ruled out. Lowrie-Fuller tests indicate that this VRM overprinting does not have a multidomain origin. An approximately linear relationship exists between median destructive field (MDF) and the logarithm of the natural remanent magnetization (NRM). Carbonate dilution does not appear to be a dominant factor in controlling variations in concentration-dependent magnetic parameters, such as magnetic susceptibility. The sedimentological distinction between Subunits IA and IB does not show up in the magnetic record. However, a sharp change in magnetic properties does occur at 32 mbsf, with low background magnetizations below this level and high background magnetizations above it. The boundary coincides with a change from thick (>10 cm thick) to thin (<10 cm thick) turbidite deposition, and is also near the boundary separating the sulfate-reduction zone in the upper part of the sequence from the sulfate-free zone beneath. The abrupt nature of the magnetic boundary is evidence that nannofossil subzone CN14b is not condensed, but is missing in a hiatus at 32 mbsf. Nine peaks have been identified in the susceptibility (K) record that are superimposed on ôbackgroundö signals. ARM/K ratios are uniformly low for the background sediments below 32 mbsf, intermediate for strong susceptibility peaks, and high for background sediments above 32 mbsf and weak susceptibility peaks. Comparisons with results from Site 820 suggest that (1) the background sediments above 32 mbsf and the weak susceptibility peaks carry a stable single-domain magnetization, and (2) the high susceptibility peaks are caused by the addition of a superparamagnetic contribution. Expectations are that the distinctive features of the Hole 823A magnetic record are linked to major environmental changes.

Curie temperatures and hysteresis properties of ODP Leg 183 sites, Kerguelen Plateau and Broken Ridge

In this manuscript, we present rock magnetic results of samples recovered during Leg 183. The Leg 183 cores were recovered from six drill sites and display variable rock magnetic properties. The differences in the rock magnetic properties are a function of mineralogy and alteration. Cretaceous subaerial basalt samples with titanomagnetite exhibit a strong Verwey transition in the vicinity of 110 K and have frequency-dependent susceptibility curves that resemble those of synthetic (titano) magnetites. These results are in good agreement with the thermomagnetic characteristics where titanomagnetites with Curie temperatures of ~580°C were identified. The hysteresis ratios suggest that the bulk magnetic grain size is in the psuedo-single-domain boundary. These subaerial basalts experienced high-temperature oxidation and maintained reliable paleomagnetic records. In contrast, the 34-Ma submarine pillow basalts do not show the Verwey transition during the low-temperature experiments. Thermomagnetic analysis shows that the remanent magnetization in this group is mainly carried by a thermally unstable mineral titanomaghemite. The frequency-dependent relationships are opposite of those from the first group and show little sign of titanomagnetite characteristics. Rocks from the third group are oxidized titanomagnetites and have multiple magnetic phases. They have irreversible thermaomagnetic curves and hysteresis ratios clustering toward the multidomain region (with higher Hcr/Hc ratios). The combined investigation suggests that variations in magnetic properties correlate with changes in lithology, which results in differences in the abundance and size of magnetic minerals. The rock magnetic data on Leg 183 samples clearly indicate that titanomagnetite is the dominant mineral and the primary remanence carrier in subaerial basalt. The generally good magnetic stability and other properties exhibited by titanomagnetite-bearing rocks support the inference that the ChRM isolated from the Cretaceous sites were acquired during the Cretaceous Normal Superchron. The stable inclinations identified from these samples are therefore useful for future tectonic studies.

Magnetic properties of ODP Hole 116-717C

Dark gray and black mud turbidites cored on ODP Leg 116 commonly yielded large magnetic susceptibility peaks. What is more, these peaks displayed different shapes suggesting variations in sedimentological processes. Consequently, a detailed study of the magnetic properties of two of these turbidites was undertaken to better understand the source of their unusual magnetism. Physical properties were measured as was the demagnetization behavior of sample natural remanent magnetizations (NRMs). Subsequently, an anhysteretic remanent magnetization (ARM) and saturation isothermal remanent magnetization (SIRM) were imparted to the samples, demagnetized, and various grain size tests based on the behavior of these remanences were applied. Finally, magnetic concentrates from two samples were examined with a scanning electron microscope with the capability to do energy dispersive X-ray (EDX) analysis. The turbidites stand out from surrounding layers because of their high susceptibilities, NRMs, ARMs, SIRMs, and ratios of ARM and SIRM to susceptibility. Their alternating field and thermal demagnetization properties and IRM acquisition curves are consistent with titanomagnetite grains as the primary magnetic mineral with some amount of hematite present. These properties are very similar to those published for samples from the Deccan flood basalts and suggest this formation as a possible source of the magnetic grains. Magnetic granulometry tests implied that the magnetic particles behave dominantly as single-domain and pseudo-single-domain grains. Moreover, they also implied that the large variation in susceptibility observed in the black mud turbidites results from a tenfold increase in the concentration of titanomagnetite grains. Electron microscope, EDX, and SIRM analyses revealed detrital titanomagnetites with typical sizes around 8-10 µm, but as large as 20-25 µm. These are probably the dominant magnetic grains in the black mud turbidites; however, ARM and susceptibility frequency-dependence suggested that there may also be a submicrometer fraction present. Most of the observed titanomagnetite grains are tabular and some display exsolution lamellae, accounting for the pseudo-single-domain behavior despite their moderate sizes. We hypothesize that the magnetic mineral concentration variations are brought about by sedimentological factors. The heavier magnetic minerals may tend to sink to the bottom of a turbidite; however, sometimes turbidite turbulence may act to keep these tabular, medium-size grains in suspension longer than some other larger or more equidimensional grains. Consequently, the susceptibility peak shape may reflect the turbidite current velocities as well as other sedimentological factors.

Magnetic properties of ODP Hole 109-648B

Seventeen samples from pillow or massive "zero age" fresh basalts from ODP Legs 106 and 109 were studied in order to examine their magnetic properties and oxidation degree. Thermomagnetic analyses of studied samples show Curie temperatures from 127°C to 220°C with reversible heating and cooling curves. Hysteresis parameters indicate the contribution of large Pseudo-Single Domain (PSD) grain of titanomagnetites with saturation magnetization between 0.4 and 0.7 emu/g which is almost twice that those of other recent mid-oceanic dredged basalts (e.g., FAMOUS and CYAMEX-RISE). The large grain sizes and higher magnetic mineral concentration may suggest a slower cooling of these basalts compared to those previously studied. Electron microprobe analyses of titanomagnetite grains combined with Curie point determinations give z = 0.3 for the degree of low temperature oxidation, which is close to the other values reported for low temperature oxidation of mid-oceanic ridge basalts.

Paleomagnetic of ODP Hole 197-1203A

On the basis of studies of Holocene samples,submarine basaltic glass (SBG) is thought to be an ideal paleointensity recorder because it contains unaltered single domain magnetic inclusions that yield Thellier paleointensity data of exceptional quality. To be useful as a recorder of the long-term geomagnetic field, older SBG must retain these optimal properties. Here, we examine this issue through rock magnetic and transmission electron microscope (TEM) analyses of Cretaceous SBG recovered at Ocean Drilling Program Site 1203 (northwestern Pacific Ocean). These SBG samples have very low natural remanent magnetization intensities (NRM <50 nAm**2/g) and TEM analyses indicate a correspondingly low concentration of crystalline inclusions. Thellier experiments on samples with the strongest NRM intensity (>5*10**-11 Am**2) show a rapid acquisition of thermoremanent magnetization (TRM) with respect to NRM demagnetization. Taken at face value,this behavior implies magnetization in a very weak (617 WT) ambient field. But monitoring of magnetic hysteresis properties during the Thellier experiments (on subsamples of the SBG samples used for paleointensity determinations) indicates systematic variations in values over the same temperature range where the rapid TRM acquisition is observed. A similar change in properties during heating is observed on monitor SBG specimens using low-temperature data: with progressive heatings the Verwey transition becomes more distinct. We suggest that these experimental data record the partial melting and neocrystallization of magnetic grains in SBG during the thermal treatments required by the Thellier method,resulting in paleointensity values biased to low values. We further propose that this process is pronounced in Cretaceous and Jurassic SBG (relative to Holocene SBG) because devitrification on geologic time scales (i.e., tens of millions of years) lowers the transition temperature at which the neocrystallization can commence. Magnetic hysteresis monitoring may provide a straightforward means of detecting the formation of new magnetic inclusions in SBG during Thellier experiments.

In situ control of As dimer orientation on Ge(100) surfaces

We investigated the preparation of single domain Ge(100):As surfaces in a metal-organic vapor phase epitaxy reactor. In situ reflection anisotropy spectra (RAS) of vicinal substrates change when arsenic is supplied either by tertiarybutylarsine or by background As4 during annealing. Low energy electron diffraction shows mutually perpendicular orientations of dimers, scanning tunneling microscopy reveals distinct differences in the step structure, and x-ray photoelectron spectroscopy confirms differences in the As coverage of the Ge(100): As samples. Their RAS signals consist of contributions related to As dimer orientation and to step structure, enabling precise in situ control over preparation of single domain Ge(100): As surfaces.

Certificados electrónicos de servidor en administración y comercio electrónicos: garantías de seguridad

El uso de Internet por parte de los ciudadanos para relacionarse con las Administraciones Públicas o en relación con actividades de comercio electrónico crece día a día. Así lo evidencian los diferentes estudios realizados en esta materia, como los que lleva a cabo el Observatorio Nacional de las Telecomunicaciones y la Sociedad de la Información (http://www.ontsi.red.es/ontsi/). Se hace necesario, por tanto, identificar a las partes intervinientes en estas transacciones, además de dotarlas de la confidencialidad necesaria y garantizar el no repudio. Uno de los elementos que, junto con los mecanismos criptográficos apropiados, proporcionan estos requisitos, son los certificados electrónicos de servidor web. Existen numerosas publicaciones dedicadas a analizar esos mecanismos criptográficos y numerosos estudios de seguridad relacionados con los algoritmos de cifrado, simétrico y asimétrico, y el tamaño de las claves criptográficas. Sin embargo, la seguridad relacionada con el uso de los protocolos de seguridad SSL/TLS está estrechamente ligada a dos aspectos menos conocidos:  el grado de seguridad con el que se emiten los certificados electrónicos de servidor que permiten implementar dichos protocolos; y  el uso que hacen las aplicaciones software, y en especial los navegadores web, de los campos que contiene el perfil de dichos certificados. Por tanto, diferentes perfiles de certificados electrónicos de servidor y diferentes niveles de seguridad asociados al procedimiento de emisión de los mismos, dan lugar a diferentes tipos de certificados electrónicos. Si además se considera el marco jurídico que afecta a cada uno de ellos, se puede concluir que existe una tipología de certificados de servidor, con diferentes grados de seguridad o de confianza. Adicionalmente, existen otros requisitos que también pueden pasar desapercibidos tanto a los titulares de los certificados como a los usuarios de los servicios de comercio electrónico y administración electrónica. Por ejemplo, el grado de confianza que otorgan los navegadores web a las Autoridades de Certificación emisoras de los certificados y cómo estas adquieren tal condición, o la posibilidad de poder verificar el estado de revocación del certificado electrónico. El presente trabajo analiza todos estos requisitos y establece, en función de los mismos, la correspondiente tipología de certificados electrónicos de servidor web. Concretamente, las características a analizar para cada tipo de certificado son las siguientes:  Seguridad jurídica.  Normas técnicas.  Garantías sobre la verdadera identidad del dominio.  Verificación del estado de revocación.  Requisitos del Prestador de Servicios de Certificación. Los tipos de certificados electrónicos a analizar son:  Certificados de servidor web:  Certificados autofirmados y certificados emitidos por un Prestador de Servicios de Certificación.  Certificados de dominio simple y certificados multidominio (wildcard y SAN)  Certificados de validación extendida.  Certificados de sede electrónica. ABSTRACT Internet use by citizens to interact with government or with e-commerce activities is growing daily. This topic is evidenced by different studies in this area, such as those undertaken by the Observatorio Nacional de las Telecomunicaciones y la Sociedad de la Información (http://www.ontsi.red.es/ontsi/ ). Therefore, it is necessary to identify the parties involved in these transactions, as well as provide guaranties such as confidentiality and non-repudiation. One instrument which, together with appropriate cryptographic mechanisms, provides these requirements is SSL electronic certificate. There are numerous publications devoted to analyzing these cryptographic mechanisms and many studies related security encryption algorithms, symmetric and asymmetric, and the size of the cryptographic keys. However, the safety related to the use of security protocols SSL / TLS is closely linked to two lesser known aspects:  the degree of security used in issuing the SSL electronic certificates; and  the way software applications, especially web Internet browsers, work with the fields of the SSL certificates profiles. Therefore, the diversity of profiles and security levels of issuing SSL electronic certificates give rise to different types of certificates. Besides, some of these electronic certificates are affected by a specific legal framework. Consequently, it can be concluded that there are different types of SSL certificates, with different degrees of security or trustworthiness. Additionally, there are other requirements that may go unnoticed both certificate holders and users of e-commerce services and e-Government. For example, the degree of trustworthiness of the Certification Authorities and how they acquire such a condition by suppliers of Internet browsers, or the possibility to verify the revocation status of the SSL electronic certificate. This paper discusses these requirements and sets, according to them, the type of SSL electronic certificates. Specifically, the characteristics analyzed for each type of certificate are the following:  Legal security.  Technical standards.  Guarantees to the real identity of the domain.  Check the revocation status.  Requirements of the Certification Services Providers. The types of electronic certificates to be analyzed are the following:  SSL electronic certificates:  Self-signed certificates and certificates issued by a Certification Service Provider.  Single-domain certificates and multi-domain certificates (wildcard and SAN)  Extended Validation Certificates.  “Sede electrónica” certificates (specific certificates for web sites of Spanish Public Administrations).

Guiding functional connectivity estimation by structural connectivity in MEG: an application to discrimination of mild cognitive impaired conditions

Whole brain resting state connectivity is a promising biomarker that might help to obtain an early diagnosis in many neurological diseases, such as dementia. Inferring resting-state connectivity is often based on correlations, which are sensitive to indirect connections, leading to an inaccurate representation of the real backbone of the network. The precision matrix is a better representation for whole brain connectivity, as it considers only direct connections. The network structure can be estimated using the graphical lasso (GL), which achieves sparsity through l1-regularization on the precision matrix. In this paper, we propose a structural connectivity adaptive version of the GL, where weaker anatomical connections are represented as stronger penalties on the corre- sponding functional connections. We applied beamformer source reconstruction to the resting state MEG record- ings of 81 subjects, where 29 were healthy controls, 22 were single-domain amnestic Mild Cognitive Impaired (MCI), and 30 were multiple-domain amnestic MCI. An atlas-based anatomical parcellation of 66 regions was ob- tained for each subject, and time series were assigned to each of the regions. The fiber densities between the re- gions, obtained with deterministic tractography from diffusion-weighted MRI, were used to define the anatomical connectivity. Precision matrices were obtained with the region specific time series in five different frequency bands. We compared our method with the traditional GL and a functional adaptive version of the GL, in terms of log-likelihood and classification accuracies between the three groups. We conclude that introduc- ing an anatomical prior improves the expressivity of the model and, in most cases, leads to a better classification between groups.

Identification of a cytochrome b-type NAD(P)H oxidoreductase ubiquitously expressed in human cells

Cytochrome b-type NAD(P)H oxidoreductases are involved in many physiological processes, including iron uptake in yeast, the respiratory burst, and perhaps oxygen sensing in mammals. We have identified a cytosolic cytochrome b-type NAD(P)H oxidoreductase in mammals, a flavohemoprotein (b5+b5R) containing cytochrome b5 (b5) and b5 reductase (b5R) domains. A genetic approach, using blast searches against dbest for FAD-, NAD(P)H-binding sequences followed by reverse transcription–PCR, was used to clone the complete cDNA sequence of human b5+b5R from the hepatoma cell line Hep 3B. Compared with the classical single-domain b5 and b5R proteins localized on endoplasmic reticulum membrane, b5+b5R also has binding motifs for heme, FAD, and NAD(P)H prosthetic groups but no membrane anchor. The human b5+b5R transcript was expressed at similar levels in all tissues and cell lines that were tested. The two functional domains b5* and b5R* are linked by an approximately 100-aa-long hinge bearing no sequence homology to any known proteins. When human b5+b5R was expressed as c-myc adduct in COS-7 cells, confocal microscopy revealed a cytosolic localization at the perinuclear space. The recombinant b5+b5R protein can be reduced by NAD(P)H, generating spectrum typical of reduced cytochrome b with alpha, beta, and Soret peaks at 557, 527, and 425 nm, respectively. Human b5+b5R flavohemoprotein is a NAD(P)H oxidoreductase, demonstrated by superoxide production in the presence of air and excess NAD(P)H and by cytochrome c reduction in vitro. The properties of this protein make it a plausible candidate oxygen sensor.

Limited internal friction in the rate-limiting step of a two-state protein folding reaction

Small, single-domain proteins typically fold via a compact transition-state ensemble in a process well fitted by a simple, two-state model. To characterize the rate-limiting conformational changes that underlie two-state folding, we have investigated experimentally the effects of changing solvent viscosity on the refolding of the IgG binding domain of protein L. In conjunction with numerical simulations, our results indicate that the rate-limiting conformational changes of the folding of this domain are strongly coupled to solvent viscosity and lack any significant “internal friction” arising from intrachain collisions. When compared with the previously determined solvent viscosity dependencies of other, more restricted conformational changes, our results suggest that the rate-limiting folding transition involves conformational fluctuations that displace considerable amounts of solvent. Reconciling evidence that the folding transition state ensemble is comprised of highly collapsed species with these and similar, previously reported results should provide a significant constraint for theoretical models of the folding process.

Structural determinants of oxidative folding in proteins

A method for determining the kinetic fate of structured disulfide species (i.e., whether they are preferentially oxidized or reshuffle back to an unstructured disulfide species) is introduced. The method relies on the sensitivity of unstructured disulfide species to low concentrations of reducing agents. Because a structured des species that preferentially reshuffles generally first rearranges to an unstructured species, a small concentration of reduced DTT (e.g., 260 μM) suffices to distinguish on-pathway intermediates from dead-end species. We apply this method to the oxidative folding of bovine pancreatic ribonuclease A (RNase A) and show that des[40–95] and des[65–72] are productive intermediates, whereas des[26–84] and des[58–110] are metastable dead-end species that preferentially reshuffle. The key factor in determining the kinetic fate of these des species is the relative accessibility of both their thiol groups and disulfide bonds. Productive intermediates tend to be disulfide-secure, meaning that their structural fluctuations preferentially expose their thiol groups, while keeping their disulfide bonds buried. By contrast, dead-end species tend to be disulfide-insecure, in that their structural fluctuations expose their disulfide bonds in concert with their thiol groups. This distinction leads to four generic types of oxidative folding pathways. We combine these results with those of earlier studies to suggest a general three-stage model of oxidative folding of RNase A and other single-domain proteins with multiple disulfide bonds.

Compressibility as a means to detect and characterize globular protein states.

We report compressibility data on single-domain, globular proteins which suggest a general relationship between protein conformational transitions and delta kzeroS, the change in the partial specific adiabatic compressibility which accompanies the transition. Specifically, we find transitions between native and compact intermediate states to be accompanied by small increases in kzeroS of +(1-4) x 10(-6) cm3.g-1.bar-1 (1 bar = 100 kPa). By contrast, transitions between native and partially unfolded states are accompanied by small decreases in kzeroS of -(3-7) x 10(-6) cm3.g-1.bar-1, while native-to-fully unfolded transitions result in large decreases in kzeroS of -(18-20) x 10(-6) cm3.g-1.bar-1. Thus, for the single-domain, globular proteins studied here, changes in kzeroS correlate with the type of transition being monitored, independent of the specific protein. Consequently, kzeroS measurements may provide a convenient approach for detecting the existence of and for defining the nature of protein transitions, while also characterizing the hydration properties of individual protein states.

Crystal structure of the cell cycle-regulatory protein suc1 reveals a beta-hinge conformational switch.

The Schizosaccharomyces pombe cell cycle-regulatory protein suc1, named as the suppressor of cdc2 temperature-sensitive mutations, is essential for cell cycle progression. To understand suc1 structure-function relationships and to help resolve conflicting interpretations of suc1 function based on genetic studies of suc1 and its functional homologs in both lower and higher eukaryotes, we have determined the crystal structure of the beta-interchanged suc1 dimer. Each domain consists of three alpha-helices and a four-stranded beta-sheet, completed by the interchange of terminal beta-strands between the two subunits. This beta-interchanged suc1 dimer, when compared with the beta-hairpin single-domain folds of suc1, reveals a beta-hinge motif formed by the conserved amino acid sequence HVPEPH. This beta-hinge mediates the subunit conformation and assembly of suc1: closing produces the intrasubunit beta-hairpin and single-domain fold, whereas opening leads to the intersubunit beta-strand interchange and interlocked dimer assembly reported here. This conformational switch markedly changes the surface accessibility of sequence-conserved residues available for recognition of cyclin-dependent kinase, suggesting a structural mechanism for beta-hinge-mediated regulation of suc1 biological function. Thus, suc1 belongs to the family of domain-swapping proteins, consisting of intertwined and dimeric protein structures in which the dual assembly modes regulate their function.

Paleomagnetic and rock magnetic properties of ODP Leg 173 sites, west Iberia continental margin

We present detailed paleomagnetic and rock magnetic results of rock samples recovered during Leg 173. The Leg 173 cores display a multicomponent magnetization nature. Variations in magnetic properties correlate with changes in lithology that result from differences in the abundance and size of magnetic minerals. The combined investigation suggests that the magnetic properties of the "fresher" peridotite samples from Site 1070 are controlled mainly by titanomagnetite, with a strong Verwey transition in the vicinity of 110 K, and with field- and frequency-dependent susceptibility curves that resemble those of titanomagnetites. These results are in excellent agreement with thermomagnetic characteristics where titanomagnetites with Curie temperature ~580°C were identified from the "fresher" peridotites. In contrast to the magnetic properties observed from the "fresher" peridotites, the low-temperature curves for the "altered" peridotites did not show any Verwey transition. Thermomagnetic analysis using the high-temperature vibrating sample magnetometer also failed to show evidence for titanomagnetites. The remanent magnetization is carried by a thermally unstable mineral that breaks down at ~420°C, probably maghemite. The field- and frequency-dependent relationships are also directly opposite to those in the reversal zone, with no signs of titanomagnetite characteristics. Altogether, these rock magnetic data seem to be sensitive indicators of alteration and support the contention that maghemite is responsible for the magnetic signatures displayed in the altered peridotites of the upper section. The magnetic minerals of the basement rocks from Sites 1068, 1069, and 1070 are of variable particle size but fall within the pseudo-single-domain size range (0.2-14 µm). The average natural remanent magnetization (NRM) intensity of recovered serpenitinized peridotite is typically on the order of 20 mA/m for samples from Site 1068, but ~120 mA/m for samples from Site 1070. The much stronger magnetization intensity of Site 1070 is apparently in excellent agreement with the observed magnetic anomaly high. Nearly half of the NRM intensity remained after 400°C demagnetization, suggesting that the remanence can contribute significantly to the marine magnetic anomaly.

Focused ion beam manufacturing of magnetic nanostructures

A number of patterning methods including conventional photo-lithography and E-beam lithography have been employed to pattern devices with critical dimensions of submicrometer levels. The methods of device fabrication by lithography and multilevel processing are usually specific to the chemical and physical properties of the etchants and materials used, and require a number of processing steps. As an alternative, focused ion beam (FIB) lithography is a unique and straightforward tool to rapidly develop nanomagnetic prototyping devices. This feature of FIB is critical to conduct the basic study necessary to advance the state-of-the-art in magnetic recording. ^ The dissertation develops a specific design of nanodevices and demonstrates FIB-fabricated stable and reproducible magnetic nanostructures with a critical dimension of about 10 nm. The project included the fabrication of a patterned single and multilayer magnetic media with areal densities beyond 10 Terabit/in 2. Each block had perpendicular or longitudinal magnetic anisotropy and a single domain structure. The purpose was to demonstrate how the ability of FIB to directly etch nanoscale patterns allowed exploring (even in the academic environment) the true physics of various types of nanostructures. ^ Another goal of this study was the investigation of FIB patterned magnetic media with a set of characterization tools: e.g. Spinstand Guzik V2002, magnetic force microscopy, scanning electron microscopy with energy dispersive system and wavelength dispersive system. ^ In the course of this work, a unique prototype of a record high density patterned magnetic media device capable of 10 terabit/in 2 was built. The read/write testing was performed by a Guzik spinstand. The readback signals were recorded and analyzed by a digital oscilloscope. A number of different configurations for writing and reading information from a magnetic medium were explored. The prototype transducers for this work were fabricated via FIB trimming of different magnetic recording heads. ^