Search

Because of safety concerns associated with friction testing on both high-and low-speed facilities, testing at variable speeds has been investigated by the Florida Department of Transportation (DOT) and others. Previous research has demonstrated that reasonable correlations may be developed between friction test data obtained at the standard test speed of 40 mph (64.4 km/h) and other speeds. As part of an effort to harmonize its fleet of full-scale, locked-wheel friction testing equipment with portable reference test equipment (ASTM E 1960), the Florida DOT also evaluated the skid number speed gradient ( Gv) for use in transforming friction and macrotexture measurements obtained at variable highway speeds. This paper documents the results of this evaluation. On the basis of the results of this study, a practical method of measuring pavement friction and macrotexture at variable highway speeds with the Florida DOT locked-wheel test unit and the ribbed tire is presented. Since the results of the ribbed tire test are known to be significantly influenced by pavement microtexture and since the mean profile depth (MPD), as measured with the high-speed laser, is a direct measure of macrotexture, the friction number (FN)40 R and the complementary MPD data together may be readily employed to characterize the frictional properties of the pavement. This approach builds on Florida's historical database of locked-wheel, ribbed-tire test data, while adding a direct measure of macrotexture and the flexibility of testing at variable speeds. Practical implementation recommendations and examples are provided.

An experiment was conducted to study differences in workload and performance of participants when navigating a route inside a building. Participants used a personal digital assistant (PDA) which presented three different types of spatial information. The spatial information varied in complexity. Spatial information was presented as a sequence of maps which were advanced by the user according to location. This method of presentation captures the essence of a location-based service; the spatial information presented is only relevant at that location. Results show significantly shorter route completion times and lower mental workload for participants using the simplified information when compared to the more complex information. Implications for the design of location-based navigation support on small-screen devices are discussed.

Mafic dykes of different ages were collected from three different tectonic settings and analyzed using anisotropy of magnetic susceptibility (AMS) as a proxy for magmatic flow during intrusion. In Iceland, ridge-parallel basaltic dykes were sampled on each side of the active tectonic boundary. The dykes are K max orientation indicating vertical emplacement. The Eocene Aishihik dyke swarm intrudes the Yukon–Tanana terrane in the Yukon province, Canada over an area ~ 200 by 60 km. These dykes were intruded normal to the accretionary margin, are porphyritic andesites, and have an intermediate geochemical signature based on major and trace element analyses. Ten dykes were sampled and 111 cores analyzed using AMS, and the dykes preserve a vertical K max orientation, indicating intrusion was vertical through ~ 30 km of continental crust. The 2.06 Ga Kenora–Kabetogama dykes in northern Minnesota and western Ontario crosscut a variety of Archean terranes (thickness ~ 50 km) in a radiating pattern. The unmetamorphosed basaltic dykes are 1–120 m wide, 10–110 km in length, are vertical in orientation and can be grouped as either being single intrusion or multiple intrusion (composite) dykes. AMS data preserve a vertical K max orientation for the southerly locations (2 dykes, n = 53) and horizontal K max for the remainder to the northwest (15 dykes, n = 194). Maximum magnetic susceptibility axes (4 dykes, n = 92) for composite dykes are scattered and yield inconsistent flow directions with regard to the dyke margin. Almost all of our results are “normal” in that, the magnetic foliation (the plane containing K max and K int , normal to K min ) is parallel to the dyke planes, which gives us confidence that the magnetic lineations (i.e., K max orientations) are parallel to magmatic flow.

In recent years, larger vibratory rollers have been implemented because of their improved efficiency. An unfortunate consequence is that greater ground motion caused by these larger vibratory rollers might damage adjacent infrastructure, particularly in or near urban areas. Various federal, state, and foreign agencies have proposed vibration limit criteria; some are intended to mitigate damage to structures while others are based on limiting human annoyance. Two of these existing criteria (U.S. Office of Surface Mines blasting level criteria and German DIN 4150 standard level for human annoyance) were selected to form the basis of a recommended practice for limiting vibratory compaction in critical work zones. These criteria are used to differentiate three zones on a plot of peak particle velocity versus vibratory roller frequency. A square-root scaling law of ground motion is used to predict the ground motions from vibratory compaction equipment based on falling weight deflectometer (FWD) data. With this predictor, a potentially vibration-sensitive portion of a resurfacing project can be identified using displacement time histories from the FWD obtained during routine preconstruction testing. Detailed knowledge of the layering of the pavement structure or the geology of the surrounding site is not required. It is demonstrated that this predictor can successfully be used to restrict vibratory compaction near sensitive structures, including fragile buried infrastructure.

An experiment was conducted to study differences in workload and performance of participants when navigating a route. Participants used a mobile device to navigate a route in a building. Different types of representation were used: a paper floor plan and three representations presented on a personal digital assistant (PDA). In the PDA based conditions, an overview of the floor plan was presented in a picture viewer. Since the plan was much larger than the PDA screen, participants moved different parts of the plan into view using a stylus. Floor plans were also presented as a sequence of plan fragments on the PDA which were advanced by the user according to location. Results show significantly shorter route completion times for participants using the paper plan compared with the PDA support. Significant differences in workload, effort and mental demand were also found between the types of representation. The paper plan condition elicited the lowest levels of workload and the shortest route completion times. Implications for the design of location-based navigation support are discussed.

The low-temperature magnetic properties of the Neuschwanstein EL6 meteorite as well as of the daubreelite (FeCr2S4), troilite (FeS), and FeNi mineral phases were investigated. Low-temperature magnetic behavior of the Neuschwanstein meteorite appears to be controlled mostly by FeNi. However, two magnetic features at ∼ 70 K (Tm) and 150 K (Tc), are due to a magnetic transition in and Curie temperature of ferrimagnetic daubreelite. The ∼ 10 K variations in Tm and Tc among daubreelite in the Neuschwanstein meteorite, daubreelite from the Coahuila meteorite and synthetic daubreelite [Tsurkan, V., Baran, M., Szymczak, R., Szymczak, H., Tidecks, R., 2001a. Spin-glass like states in the ferrimagnet FeCr2S4. Physica B, 296, 301−305.] might be due to slightly different Fe/Cr stoichiometric ratios, the presence of impurities, or crystalline lattice defects. In the antiferromagnetic troilite a magnetic transition at Tm ∼ 60 K was identified. Its nature seems to be most likely due to a change in the orientation and attendant canting of the antiparallel spins. However, this feature was not identified in the Neuschwanstein meteorite measurements because of low concentration and weak magnetization of the troilite phase compared to those of FeNi and daubreelite. Daubreelite with its Tc ∼ 160 K might be a significant magnetic mineral in cold environment. Low-temperature magnetic data of daubreelite, troilite and FeNi presented here are useful for the interpretation of the low-temperature magnetic measurements of various extraterrestrial materials and for the identification of the presence of these phases.

This paper presents a framework for evaluating the reliability of probe-sourced traffic speed data for congestion detection and general infrastructure performance assessment. The methodology outlined employs pattern recognition and time-series analysis to accurately quantify the similarity and dissimilarities between probe-sourced and benchmarked local sensor data. First, an adaptive and multiscale pattern recognition algorithm called Empirical Mode Decomposition (EMD) is used to define short, medium and long-term trends for the probe-sourced and infrastructure mounted local sensor datasets. The reliability of the probe data is then estimated based on the similarity or synchrony between corresponding trends. The synchrony between long-term trends are used as a measure of accuracy for general performance assessment, whereas short and medium term trends are used for testing the accuracy of congestion detection with probe-sourced data. Using one-month of high-resolution speed data, the authors were able to use probe data to detect on average 74% and 63% of the short-term events (events lasting for at most 30 minutes), 95% and 68% of the medium-term events (events lasting between 1 and 3 hours) on freeways and non - freeways respectively. Significant latencies do however exist between both datasets. On non - freeways, the benchmarked data detected events, on average, 12 minutes earlier than the probe data. On freeways, the latency between the datasets was reduced to 8 minutes. The resulting framework can serve as a guide for state DOTs when outsourcing or supplementing traffic data collection to probe-based services.

A software tool MatchMaps was designed to facilitate matching between geospatial features held in different datasets, especially an authoritative dataset and a crowd-sourced dataset. MatchMaps is not fully automatic; it requires human interaction to resolve problematic matching cases. Previous studies have shown that this approach results in higher precision and recall than those achieved by fully automatic tools. In this study, we aim to evaluate MatchMaps with respect to the amount of human effort required for matching, and compare it with a fully manual matching process.

Magnetism is a phenomenon associated with only a handful of elements, of which iron is the most common in geologic materials. In the mantle and crust, iron occurs as silicates, oxides, sulfides, and oxyhydroxides, with an immense variety of magnetic characteristics, including ferromagnetism and the ability to acquire and retain remanent magnetization in the weak geomagnetic field. This chapter reviews the essential physical and mineralogical origins of magnetism in near-surface earth materials responsible for remanent and induced magnetic anomalies. We summarize the key magnetic properties of common classes of geomaterials and their contributions to local magnetic fields and provide examples of selected applications of magnetism in studying surficial processes. A better understanding of the magnetic properties responsible for a particular magnetic anomaly is essential for a more reliable geologic, archaeological, or environmental interpretation of the subsurface.

Background. There is good evidence now that cognitive behaviour therapy (CBT) is effective in the treatment of people suffering from schizophrenia. There is also some evidence that the benefits of CBT persist after the end of treatment and that the direct costs of providing CBT as an adjunct to standard care are no higher than the direct costs of standard care alone. The aims of the present study were to discover if the benefits of CBT for acute schizophrenia which were found 1 year after index admission persist for another year, and to evaluate the comparative costs of providing CBT.Method. Consecutive admissions meeting criteria were recruited. After screening, 43 were assigned at random to a treatment-as-usual (TAU) control group and 47 were assigned to TAU plus CBT. Patients (73% of original) were rated on symptoms and social functioning 2 years after index admission. An evaluation of the direct costs of services was also completed.Results. The CBT group had maintained its advantage over the TAU group on negative symptoms and social functioning but had lost the advantage it previously enjoyed in positive symptoms. The difference between groups in total direct costs over the 2 years was not statistically significant despite the cost of providing CBT.Conclusions. Some of the benefits of CBT for patients suffering acute psychotic episodes persist for 2 years. After the end of regular treatment, CBT should probably be targeted on the appearance of early signs of relapse to forestall the re-emergence of positive symptoms.

The Twin Sisters dunite massif, Washington State, provides unweathered peridotites for magnetic analysis. These rocks have been chosen to test a new magnetic fabric based on measuring the anisotropy of magnetic susceptibility (AMS) in high-field with a vibrating sample magnetometer. Although the dunites are fresh, they host small quantities of secondary magnetite formed along cracks. Under low-field conditions magnetite masks the magnetic fabric of olivine, and thus the magnetic fabric does not reflect mantle flow deformation. Above the magnetic saturation, at a field of 1 T, the ferrimagnetic component is removed and the high-field slope represents the paramagnetic AMS only. This high-field AMS originates from the magnetocrystalline anisotropy of olivine. The high-field AMS are compared with lattice preferred orientation (LPO) fabric data obtained by electron backscatter diffraction. LPO point distributions are formed by high-temperature plastic flow, and match the high-field measurements. In contrast, girdle LPOs present notable departures from the high-field AMS axes.

SUMMARY Temperature dependence of magnetic susceptibility (χ−T) has been widely used to determine changes in mineralogy of natural samples during heat treatment. We carried out integrated rock magnetic experiments to interpret the χ−T curves of the Chinese loess/palaeosols in argon. We used both raw materials and heated samples. In addition, we also investigated the magnetic properties of magnetic extracts and residues to quantify contributions from each fraction to the bulk magnetic properties. For the heating curves, the susceptibility loss (∼30 per cent) between ∼300–400 °C is caused by the inversion from pedogenic fine-grained maghemite to haematite, suggesting that the susceptibility loss can be used as a new concentration index of the pedogenic fine-grained superparamagnetic (SP) particles in the Chinese loess/palaeosols. Unlike the warming curves, the cooling curves are dominated by newly formed fine-grained magnetites with a dominant size of ∼35 nm. The onset for the new production of these fine-grained magnetic particles occurs at ∼400 °C. It is interesting that the room-temperature magnetic susceptibility (χph) of the samples heated after a 700 °C run is independent of the degree of pedogenesis and saturates at approximately 33–35 × 10−7 m3 kg−1, indicating that the susceptibility enhancement is controlled only by the reduction of Fe-bearing aeolian minerals during heating. It appears that the 700 °C thermal treatment in argon could be in some sense an analogue to the pedogenic processes. Thus, we predict that ∼33–35 × 10−7 m3 kg−1 is the maximum susceptibility that pedogenesis can generate for the last interglacial palaeosol unit (S1). In practice, χph would be useful to quantify the aeolian inputs to the Chinese Loess plateau.

Low-field magnetic susceptibility has been widely used to determine the pedostratigraphy of the Chinese loess/paleosol sequences. However, uncertainties remain in correlating between the loess magnetic susceptibility and the marine oxygen isotope records because susceptibility variations are affected by both global and local paleoclimatic changes. To provide a more sound paleoclimatic interpretation of magnetic susceptibility variations, age models across Marine Oxygen Isotope Stage (MIS) 5 for the Jiuzhoutai (JZT) and Yuanbao (YB) sections, western Chinese Loess Plateau, were constructed through an integrated approach by linking the major pedostratigraphic boundaries of the loess profiles to the SPECMAP oxygen isotope curve, and by correlating relative magnetic paleointensity records with both the SINT800 global paleointensity stack from marine sediments and 36Cl records from the GRIP ice core. Results indicate good correlation of SIRM60 mT (a residual remanence of saturation isothermal remanent magnetization after a 60 mT alternating field demagnetization) variations between these two sites, which agree well with fluctuations in subtropical Atlantic sea surface temperatures. All cooling events recorded by ice-core and Atlantic marine sediments within MIS5 have counterparts in SIRM60 mT. SIRM60 mT is partially controlled by the degree of low-temperature oxidation, which is strongly temperature dependent. However, strong pedogenesis can decrease SIRM60 mT due to further oxidation of partially oxidized magnetites above some critical points. Therefore, we propose that SIRM60 mT is best suited to record paleotemperature changes in loess profiles from the western Chinese Loess Plateau, where pedogenesis is the weakest. Furthermore, by inter-profile correlation between the YB and JZT sections, we note that the seemingly uniform sub-paleosol unit with a broad susceptibility peak (previously assigned to MIS5c) between ∼34.4 and ∼37.4 m in the YB profile actually consists of two independent units (lower part of S1L1/MIS5b and S1S2/MIS5c). This indicates that susceptibility values can be strongly affected by local factors (e.g., mainly precipitation). Therefore, beside the simplistic traditional paleoclimatic interpretation of variations in loess susceptibility involving only cold/dry and warm/humid scenarios, cold/humid and warm/dry scenarios should also be considered.

We have examined finely exsolved oxides of the hematite-ilmenite solid-solution series found in slowly cooled middle Proterozoic igneous and metamorphic rocks. These oxides impart unusually strong and stable remanent magnetization. Transmission electron microscopy (TEM) analysis shows multiple generations of ilmenite and hematite exsolution lamellae, with lamellar thicknesses ranging from millimeters to 1-2 nanometers. Rock-magnetic experiments suggest that the remanence is thermally locked to the antiferromagnetism of the hematite component of the intergrowths, yet is stronger than expected for a canted antiferromagnetic hematite or coexisting paramagnetic Fe-Ti- ordered (R 3) ilmenite. In alternating field experiments a stable magnetization is observed in these samples to fields of 100 to 120 mT, indicating that the natural remanent magnetization (NRM) is stable over billions of years. This feature has implications for understanding magnetism of deep rocks on Earth, or on planets like Mars that no longer have a magnetic field. Atomic-scale simulations of an (R 3) ilmenite lamella in a hematite host, based on empirical cation-cation and spin-spin pair interaction parameters, show that boundary regions of the lamellae are occupied by "contact layers" with a hybrid composition of Fe ions, intermediate between Fe 2+ -rich layers in ilmenite and Fe 3+ -rich layers in hematite. In this paper we review current data and explore further the nature of the interface.

SUMMARY New rock magnetic data including low- and high-temperature thermomagnetic runs and hysteresis loops, as well as X-ray diffraction measurements, are presented from the Chinese loess/palaeosols at JiuZhoutai, on the northwestern margin of the Chinese loess plateau, to provide sound constraints on the partial oxidation model of magnetites and variations in magnetic mineralogy, grain size and oxidation states of loess samples during thermal treatments from room temperature up to 700 °C. The results show that the partially oxidized magnetites in samples are first reduced, probably as a result of the burning of organic matter below 300 °C, and then reoxidized above that. However, even after heating to 700 °C the highly diminished (in size) magnetite core still remains stoichiometric as revealed by the 120 K Verwey transition. We conclude that the diffusion of Fe2+ from the magnetite core to the surrounding maghemite rim is confined to the oxidation front (magnetite-core/maghemite-rim boundary), and has less effect on the stoichiometry of the magnetite core. The new results also reveal that the absolute number of superparamagnetic grains (magnetite/maghemite) remains relatively stable during heating. Furthermore, the left-downward shift in the data points of Day plots (mainly between 25 and 150 °C) is caused by a decrease in the oxidation gradient. In contrast, the right-upward (mainly between 500 and 650 °C) shift of the Day plots corresponds to a much higher degree of oxidation, resulting in the increase of a new oxidation gradient between the magnetite core (or the residual maghemite mantle) and the newly developed haematite outer rim, which is transformed from maghemite by heating. These new results place strong constraints on the fidelity of palaeomagnetic results from the Chinese loess constructed by thermal demagnetization, and provide a more accurate interpretation of the Day plot and low-temperature magnetic behaviours for these partially oxidized magnetites. Furthermore, this study provides robust lines of evidence for the core–rim coupling model between different magnetic phases (magnetite, maghemite and haematite).

SUMMARY The separation of paramagnetic and ferromagnetic anisotropy of magnetic susceptibility (AMS) is achieved in this study by using a vibrating sample magnetometer and a torque magnetometer performing directional anisotropy measurements in sufficiently high fields to saturate the ferromagnetic phases. The studied material, a migmatite from Minnesota, has a magnetic mineralogy characterized by ferrimagnetic multidomain titanomagnetite, paramagnetic biotite and a diamagnetic quartzo-feldspathic matrix. The low-field AMS represents the sum of ferromagnetic and paramagnetic contributions because the quartz contribution can be neglected, its magnetic susceptibility being two orders of magnitude smaller than that of biotite. In contrast, measurements in a high field isolate the paramagnetic component of the magnetic fabric. The high-field AMS is consistent between specimens and correlates well with measurements done using the torque magnetometer. The magnetic fabrics of the ferromagnetic and of the paramagnetic minerals are not co-axial, i.e. the subfabrics of the biotite and the magnetite are distinct. We propose that this non-coaxiality is due to a vorticity component during regional deformation and that it reflects the general conditions of deep crustal orogenic deformation.

SUMMARY In order to better document the climatic origin of pedogenized loess deposits west of Sahara, rock-magnetic measurements were performed on a Last Glacial coastal sand sequence from La Mala (LM) quarry (Lanzarote, Canary Islands) containing six interbedded loess–palaeosol units. Hysteresis and susceptibility data point to a coarse-grained magnetic enhancement in the coastal sand, which contrasts with the superparamagnetic (SP) to pseudo-single domain (PSD) behaviour of the Saharan loess and palaeosol. High- and low-temperature experiments show that oxidized titanomagnetite contributions dominate in the sand, while fine-grained (SP to PSD) iron oxidation products such as maghemite and goethite are evidenced in the Saharan loess/palaeosol units. At room temperature, the detrital PSD–multidomain titanomagnetite contribution of local origin is tentatively estimated from the AC-field dependence of magnetic susceptibility. Surface oxidation of detrital spinel grains and authigenesis of fine-grained iron oxides (including SP goethite) are proposed to explain the magnetic properties of the primarily fine, Saharan-dust-bearing material. The dry, local climate of the present-day and Late Holocene means that loess deposits are not preserved. The six pedogenized loess units, however, point to dust trapping under semi-arid, wetter conditions, probably illustrating periods of reduced latitudinal temperature gradients and climate variability of the North Atlantic climate, respectively. These findings suggest that both the Canary palaeosol and its content of (ultra)fine iron oxide might be constrained by (wet) deposition and trapping of fine Saharan dust.

We compare new anisotropy of magnetic susceptibility (AMS) data with previously-determined paleoclimatically sensitive parameters for a loess profile at Lingtai, central Loess Plateau, China, to unravel factors that control loess AMS. Magnetic lineations are clustered along NE–SW and NW–SE orientations during cold and warm periods, respectively, which probably corresponded to paleowind directions of both winter and summer monsoons. Anomalously steep magnetic foliations coincidentally occur at the paleoclimatic stage boundaries, indicating sediment disturbance. Lineation strength appears to be sensitive to millennial-scale rapid paleoclimatic fluctuations. Generally, the winter monsoon produces a lower degree of lineation than the summer monsoon. Furthermore, by studying lineation subsets for the cold and warm periods, we find that the cold-interval lineation strengths co-vary with grain size over the last ∼70 ka. During the last interglacial (about 74–128 ka), the lineation and declination of the susceptibility maximum (Dec- K max ) are sensitive to rapid fluctuations in winter and summer monsoons. Long-term trends of magnetic foliation and anisotropy degree replicate grain size variations, with superimposed short-term peaks related to post-depositional compaction, as suggested by density. The AMS shape parameter ( T ) indicates oblate fabrics. These new findings will not only improve our understandings of loess AMS, but also expand the possibilities of paleoclimatic studies in the Chinese loess.

SUMMARY This paper proposes a new method to distinguish between interglacial deposits and pedogenically-overprinted glacial loess based on the concentration variations of coarse-grained aeolian (magnetically pseudo-single domain and multidomain) magnetite. We apply the method to a sequence from the upper part of the loess unit L2 (marine isotope stage MIS 6) to the sub-loess unit S1L2 (MIS 5d) at the YuanBo (YB) section in the Chinese Loess Plateau. The method is based on the differences in low temperature properties between the coarse-grained (multidomain and pseudo-single domain) detrital magnetite and the pedogenic magnetic particles including superparamagnetic (SP) particles and relatively larger (>SP) maghemite particles. The former is characterized by a crystallographic Verwey transition around 120 K. In contrast, the magnetization of the latter continuously decreases in intensity with increasing temperatures. The method involves two steps: (1) calculating the first-derivative of the low temperature thermal demagnetization of the saturated isothermal remanent magnetization acquired at 20 K (LT-SIRM), which enhances the behaviour related to the Verwey transition, and (2) fitting a third-order polynomial background to the data between both 50‐70 and 150‐ 300 K, and then subtracting this background from the total derivative curves. The area under the background-corrected derivative curves represents the absolute intensity drop associated with the Verwey transition (� J TV). This is caused by the aeolian coarse-grained magnetite, which is very sensitive to the changes in the intensity of the winter monsoon, and in turn re)

The Chinese loess/paleosol sequences can provide excellent paleomagnetic records for detailed studies on both magnetostratigraphy and secular variations of the Earth’s magnetic field. However, the nature of the loess/paleosol characteristic remanent magnetization (ChRM), isolated by thermal demagnetization from the natural remanent magnetization, still remains in debate. In this study, we directly measure the thermal, alternating field, and low-temperature demagnetization (cooling/warming cycle of remanence in zero field between 300 and 50 K) spectra of ChRM of the loess samples at Touxiangdao, Xining, PR China. The results show that coarse-grained, pseudo-single-domain (PSD)/multi-domain (MD) magnetite and PSD maghemite particles are the main magnetic carriers of the loess and paleosol ChRMs, respectively. By comparing the ChRM characteristics across a loess/paleosol transition zone, we have found that during pedogenesis, the thermally separable ChRM (original detrital remanent magnetization) carried by the PSD/MD magnetite in loess is gradually overprinted by the chemical remanent magnetization carried by PSD maghemite. Even moderate pedogenesis (e.g., for the pedogenically altered loess) can strongly affect the loess ChRM. Thus more attention has to be focused on the paleosol ChRM separated solely by thermal demagnetization, especially when constructing a continuous paleomagnetic record covering both loess and paleosol units.

(2003). The safety of the realm in retrospect and prospect. The RUSI Journal: Vol. 148, No. 4, pp. 55-59.

Inter-laboratory and absolute calibrations of rock magnetic parameters are fundamental for grounding a rock magnetic database and for semi-quantitative estimates about the magnetic mineral assemblage of a natural sample. Even a dimensionless ratio, such as anhysteretic susceptibility normalized by magnetic susceptibility (Ka/K) may be biased by improper calibration of one or both of the two instruments used to measure Ka and K. In addition, the intensity of the anhysteretic remanent magnetization (ARM) of a given sample depends on the experimental process by which the remanence is imparted. We report an inter-laboratory calibration of these two key parameters, using two sets of artificial reference samples: a paramagnetic rare earth salt, Gd2O3 and a commercial “pozzolanico” cement containing oxidized magnetite with grain size of less than 0.1 μm according to hysteresis properties. Using Gd2O3 the 10 Kappabridges magnetic susceptibility meters (AGICO KLY-2 or KLY-3 models) tested prove to be cross-calibrated to within 1%. On the other hand, Kappabridges provide a low-field susceptibility value that is ca. 6% lower than the tabulated value for Gd2O3, while average high-field susceptibility values measured on a range of instruments are indistinguishable from the tabulated value. Therefore, we suggest that Kappabridge values should be multiplied by 1.06 to achieve absolute calibration. Bartington Instruments magnetic susceptibility meters with MS2B sensors produce values that are 2–13% lower than Kappabridge values, with a strong dependence on sample centering within the sensor. The Ka/K ratio of ca. 11, originally obtained on discrete cement samples with a 2G Enterprises superconducting rock magnetometer and a KLY-2, is consistent with reference parameters for magnetites of grain size

The 21 papers in this special issue focus on interoperability architectures and arrangements for multi-disciplinary earth observation systems and applications.

SUMMARY Most rocks contain both ferromagnetic and paramagnetic minerals that contribute to their bulk magnetic susceptibility and the anisotropy of magnetic susceptibility. Anisotropy of magnetic susceptibility techniques typically measure the net susceptibility and are not able to separate paramagnetic and ferromagnetic contributions. Since different minerals may form at various times and/or under different conditions, examination of their individual contributions provides unique information related to the rock’s formation and evolution. By subjecting a sample to high magnetic fields, the ferromagnetic minerals become saturated and the contribution of the paramagnetic minerals can be evaluated (the slope of the line at high field values, on a field vs magnetization plot). Using this approach, we developed a new technique that separates the ferromagnetic and paramagnetic components of standard 1 inch cylindrical samples using a Vibrating Sample Magnetometer. This separation is tested by artificially combining separate samples with known paramagnetic-only and ferromagnetic-only behaviour. By comparing the high-field results of a combined paramagnetic and ferromagnetic signal to the classic low field alternating current susceptibility of the paramagnetic-only signal, we demonstrate that the high field anisotropy is the result solely of the paramagnetic fabric even when the low field anisotropy of magnetic susceptibility is dominated by the ferromagnetic minerals. A ferromagnetic-only fabric is calculated for the combined paramagnetic and ferromagnetic rock, by tensor subtraction of the high field (paramagnetic-only) and low field (paramagnetic plus ferromagnetic) measurements on the same sample. Application of this technique to natural samples of combined paramagnetic and ferromagnetic behaviour is discussed.

Recently, several RCTs have provided preliminary evidence that cognitive-behavioural therapy (CBT) is effective in the treatment of people suffering from schizophrenia. However, none of these trials has provided complete demonstrations of therapist adherence. Since no suitable scale existed already, the authors devised the Cognitive Therapy for Psychosis Adherence Scale (CTPAS). The main aim of the present research was to test whether the 12 items of this scale could be rated reliably. Ratings were made on 29 sessions of CBT for schizophrenia by two raters independently and their agreement was found to be at least adequate on 10 of the items of the CTPAS. Ratings were also made on relevant items of the Collaborative Study Psychotherapy Rating Scale and agreement was found to be more than adequate for three factor-based subscales derived from these items. The results suggest therapist adherence to CBT for psychosis can be rated reliably and that the CTPAS is likely to be useful in future research on this form of treatment.

Both a dramatic decline in CD8 responses and a switch to memory T cell predominance occur with aging. The extent to which the loss of responsiveness is the consequence of the accumulation of more differentiated vs intrinsically defective T cells (or both) has been unclear. Using similar conditions of Ag stimulation, we have examined the responses generated by CD8+ cells isolated from aged TCR transgenic mice. We found that the naive transgene+ CD8+ cells from aged 2C mice expressed activation markers, produced IL-2, proliferated, and differentiated into cytotoxic T cells as efficiently as their young counterparts. The extent of responsiveness and the level of the responses were comparable in both age groups regardless of the stimulatory conditions used, i.e., partial costimulation/adhesion molecule expression on APCs, or presentation of lower affinity peptide or diminished peptide concentrations. By day 4 after Ag stimulation, no significant age-related differences were observed in the number of effector cells generated nor in the levels of secreted IL-2 or IFN-γ. Upon restimulation of effector cells, IL-2 secretion and to a lesser extent TNF-α expression, but not IFN-γ secretion, were diminished with age. These findings suggest that age-associated alterations in naive CD8 cell function are not found after primary stimulation, but may become apparent upon restimulation.

The Collaborations Workshop 2014 (CW14) brought together representatives from across the research community to discuss the issues around software’s role in reproducible research. In this paper we summarise the themes, practices and ideas raised at the workshop. We also consider how the “unconference” format of the CW14 helps in eliciting information and forming future collaborations around aspects of reproducible research. In particular, we describe three distinct areas of concern which emerged from the event: collaboration readiness, capability enhancement and advocacy

This paper describes the analysis of an airborne alerting system for aircraft that are landing on closely spaced parallel runways. Such alerting systems have the potential to increase airport capac...

Chemical remagnetization of many carbonate rock units occurred by diagenetic alteration of iron sulfide precursors and by authigenesis of fine-grained magnetite, which can commonly be recognized by a distinctive set of rock-magnetic attributes. These carbonates also typically exhibit anomalously high unblocking temperatures for recent thermoviscous components that have overprinted the characteristic chemical remanence. Recent work has shown that departures from Neel theory (as applied in the model of Pullaiah et al.) can generally be attributed to VRM carried by multidomain particles, to which the theory does not apply. In the remagnetized carbonates, however, rock-magnetic data all point to an overwhelming dominance of fine superparamagnetic and stable single-domain particles. Therefore we explore possible alternative causes for the anomalous unblocking temperatures, including maghemitization and magnetocrystalline rather than shape anisotropy. New blocking–unblocking models for these cases, however, fail to match the observed behavior, leading to the conclusion that the anomalous unblocking temperatures are indeed probably attributable to multidomain carriers. A possible alternative explanation is an increase in coercivity due to maghemitization of single-domain particles after acquisition of the viscous overprint, causing a significant increase in their unblocking temperatures. New frequency-dependent susceptibility measurements at low temperatures allow us to focus on the time–temperature behavior of the particles at the superparamagnetic-stable single-domain threshold, and we find that these do closely follow the predictions of Neel theory, as formulated in the models of Pullaiah et al. and Walton–Middleton–Schmidt.

An investigation of rock magnetic properties using the temperature-dependence of susceptibility (TDS) and X-ray diffraction (XRD) analyses was conducted on specimens of the last glacial loess (L1) and the last interglacial soil (S1) along a NW-SE transect of the loess plateau in China. Parallel subsamples were used for different heating/cooling runs in an argon atmosphere to detail the TDS characteristics. Also, “thermal pre-treatment” was carried out for investigating magnetic mineral changes under oxidizing conditions. We find that the TDS behavior in the temperature interval of 250–500°C is useful in identifying the pedogenic maghemitized magnetite in both loess and paleosol, and that it can be used as a proxy of the degree of pedogenesis, which is closely linked to climatic conditions.

We used a partial heating/cooling method (Van Velzen and Dekkers, 1999) for the analysis of representative samples of the Holocene loess of the Chinese loess plateau, in order to investigate magnetic mineralogical changes during thermal treatment. The temperature-dependence of susceptibility (TDS) results show significant alteration of magnetic phases during heating and cooling, and provide further evidence that magnetite and maghemite are the dominant ferrimagnetic minerals in the Holocene eolian deposits of the loess plateau. The TDS measurements suggest that the degree of the thermally-induced alteration is closely related to pedogenesis, which is a function of climate, and thus the alteration itself could be a useful climate indicator. Our TDS results along a NW-SE transect in the loess plateau suggest that stronger pedogenesis results in higher content of maghemite and greater susceptibility decrease during thermal treatment. This behavior seems to indicate that the final product of pedogenic magnetite in Chinese loess and paleosols is maghemite, which plays an important role in the enhancement of the magnetic susceptibility of Chinese eolian deposits.

Yucca Mountain Tuff contains small titanomagnetite grains with narrow size distributions in the superparamagnetic range [Schlinger et al., 1988]. Magnetic measurements on three samples (comprising hysteresis loops at low and ambient temperatures, acquisition and demagnetization of isothermal remanent magnetization, thermal demagnetization of the saturation remanence and of a low-temperature thermoremanence, and frequency- and temperature-dependent susceptibilities) allow evaluation of the magnetic properties in terms of Neel's [1949] single-domain theory. Precise grain volume distributions have been obtained by applying the blocking volume concept to thermal demagnetization results. In contrast, an attempt to derive mean particle volumes by fitting a Langevin curve to the room temperature magnetization curves fails, probably because the precondition for the Langevin function, KV/kT≪1, is not met. It is only for the sample with the smallest grains and in weak fields (

Detailed magnetic analyses of samples from the Jiuzhoutai well section on the western Chinese Loess Plateau reveal high-resolution signals of summer monsoon change. The last interglacial period is represented here by the 8-meter thick S1 paleosol complex. We have used low-temperature remanence studies to analyze variations in the concentration of Superparamagnetic (SP) grains, which previous studies have shown to be largely of pedogenic origin. The SP concentration, interpreted as a proxy for the extent of pedogenesis, shows millennial scale variations within S1. We conclude that the last interglacial period in Asia was characterized by rapid climate fluctuations, with at least one brief return to near-glacial conditions in the middle of oxygen-isotope substage 5e.

Trajectory prediction in air trafe c management computes the most likely or the most desirable aircraft trajectories by using models of aircraft performance and atmospheric conditions, as well as measurements of aircraft states. In comparison, actual trajectories are obtained using feedback control from a pilot or autopilot to track e ight objectives, while theaircrafte iesthrough an actual atmosphere. This paperintroduces the concept ofclosedloop sensitivities, which are dee ned as differences between actual and computed trajectories per unit of modeling errors, in thepresenceof pilot/autopilotfeedback controls.Modeling errorsareexpressed asuncertain parameters and/or uncertain functions. Pilot/autopilot control actions are approximated by nonlinear feedback control laws, designedwith themethod of feedback linearization. Both theaircraft equations of motion and the feedbackcontrol laws are linearized around computed reference trajectories, and these linearized equations are used to determine expressions for closed-loop terminal sensitivities. The proposed method is applied to the Center/Terminal Radar Approach Control (TRACON) Automation System as well as e ight management systems.

Magnetic measurements have been performed on volcanic catchment rocks, present-day soils, and cored sediments from Lake Massoko, an oligotrophic maar-lake from SW Tanzania. Magnetic concentration proxies, low- and high- temperature experiments, and hysteresis behavior, suggest significant contributions of Ti-magnetite and SP/SD (oxidized) magnetite in tuff-ring material transformed by pedogenesis (modern soil, littoral sand). In contrast, the basalt is characterized by relatively low concentrations of PSD-SD magnetite. Three depth/time intervals present magnetic signatures similar to the modern soils and littoral sands, at ~43-38 kyr, ~12-1.3 kyr, and 400-300yr BP (the uppermost 30 cm). They likely correspond to humid (high-lake stand) periods, with increased pedogenic processes and runoff. Other sediments have magnetic signatures closer to the catchment basalt, possibly indicating arid/low-stand periods with increased detrital inputs from the basaltic crater wall. Sediments deposited during the Last Glacial Maximum (~38-12kyr) present high Jrs/Js-high Hcr/Hc intervals, indicating an additional high coercivity component of unknown origin.

What is the best way to promote bicycle transportation? Are people afraid to ride bicycles because motorists will run them over? Are there enough bicycle facilities available? Is promoting bicycle transportation a wise use of tax dollars? What percentage of the population currently rides bicycles? The San Diego Association of Governments allocates approximately $2 million annually on bicycling projects throughout San Diego County, California. Both the county of San Diego and the city of San Diego employ full-time bicycle coordinators. Periodically, questions and comments will arise regarding bicycling policies. “Why are they spending so much money on bicycle lanes? No one ever bicycles down this street.” “If they would build more bicycle paths, I would ride my bicycle to work instead of drive.” “How do they expect people to ride bicycles if they don’t maintain the pavement?” The San Diego County Bicycle Use and Attitude Survey was commissioned at the behest of the San Diego County Public Works Department to determine existing levels of bicycle usage and bicycling attitudes among San Diego County residents. A total of 3,800 interviews, conducted during February and March 1994 by telephone throughout the county, provided valuable insight into a large range of bicycling issues. The survey found that a majority (58 percent) of those residents polled reported that they were bicycle owners, and that a majority (68 percent) of those households in which bicycles were present reported that the adults bicycled. Respondents who bicycle chose bicycle paths, which are separated from motor vehicles, as their preferred bikeway facility. Almost three-fourths of the respondents (73 percent) stated that they did not bicycle at night. Only 15 percent of respondents who rode a bicycle at least once within the past year reported riding for transportation purposes. Over 99 percent of all respondents stated that they did not belong to a bicycling organization. A majority of respondents (over 70 percent) had not heard of various government programs that provided bicycle maps and bicycle information, and less than 10 percent of respondents have used these services. The majority of bicycling households (86 percent) reported being at least somewhat satisfied with the level of bikeway maintenance provided. Overall, survey respondents expressed support for government efforts to promote bicycle transportation.

A recent study of the relationship between spiritual experience and psychopathology (reported in detail elsewhere) suggested that psychotic phenomena could occur in the context of spiritual experiences rather than mental illness. In the present paper, this finding is illustrated with three detailed case histories. Its implications are then explored for psychopathology, for psychiatric classification, and for our understanding of the concept of mental illness. It is argued that pathological and spiritual psychotic phenomena cannot be distinguished by 1) form and content alone (as in traditional psychopathology), 2) by their relationship either with other symptoms or with pathological causes (as in psychiatric classification), or 3) by reference to the descriptive criteria of mental illness implied by the "medical" model. The distinction is shown to depend, rather, on the way in which psychotic phenomena themselves are embedded in the values and beliefs of the person concerned. This in turn is shown to have implications for diagnosis (it shows the need for clinicians to attend to the values and beliefs of individual patients), for treatment (it points to a cognitive problem-solving model), and for research in psychopathology (especially as related to the emerging sciences of dynamic brain imaging and cognitive neuroscience).

Imaging cerebral glucose metabolism with positron emission tomography (PET) has been widely used in studying Alzheimer's disease (AD) and mild cognitive impairment (MCI). In this study, we used fluoro-deoxyglucose (FDG) PET images to investigate reduced glucose metabolism in 90 AD subjects, 90 MCI subjects and 90 healthy elderly normal controls (NC). Compared to NC, the AD showed a significant hypometabolism in left and right middle temporal, left cingulate gyrus, medial frontal gyrus and left parahippocampal gyrus. Compared to NC, the MCI showed a significant hypometabolism in the right inferior temporal gyrus and right fusiform gyrus. Compared to MCIs, the AD also showed a significant hypometabolism in left and right middle temporal, left cingulate gyrus, left angular gyrus and right parahippocampal gyrus. This study demonstrates the different cerebral metabolic patterns of AD, MCI and controls. It also shows that glucose metabolism is a sensitive measure of change in cognition and functional ability in AD and MCI, and that might be valuable in predicting future cognitive decline.