Statistical evaluation of control inputs and eye movements in the use of instruments clusters during aircraft landing

Two different types of analyses were done on data from a study in which eye movements and other variables were recorded while four pilots executed landing sequences in a Boeing 737 simulation. Various conditions were manupulated, including changes in turbulence, starting position, and instrumentation. Control inputs were analyzed in the context of the various conditions and compared against ratings of workload obtained using the Cooper-Harper scale. A number of eye-scanning measures including mean dwell time and transition from one instrument to another were entered into a principal components factor analysis. The results show a differentiation between control inputs and eye-scanning behavior. This shows the need for improved definition of workload and experiments to uncover the important differences among control inputs, eye-scanning and cognitive processes of the pilot

Spire stimulates nucleation by Cappuccino and binds both ends of actin filaments.

The actin nucleators Spire and Cappuccino synergize to promote actin assembly, but the mechanism of their synergy is controversial. Together these proteins promote the formation of actin meshes, which are conserved structures that regulate the establishment of oocyte polarity. Direct interaction between Spire and Cappuccino is required for oogenesis and for in vitro synergistic actin assembly. This synergy is proposed to be driven by elongation and the formation of a ternary complex at filament barbed ends, or by nucleation and interaction at filament pointed ends. To mimic the geometry of Spire and Cappuccino in vivo, we immobilized Spire on beads and added Cappuccino and actin. Barbed ends, protected by Cappuccino, grow away from the beads while pointed ends are retained, as expected for nucleation-driven synergy. We found that Spire is sufficient to bind barbed ends and retain pointed ends of actin filaments near beads and we identified Spire's barbed-end binding domain. Loss of barbed-end binding increases nucleation by Spire and synergy with Cappuccino in bulk pyrene assays and on beads. Importantly, genetic rescue by the loss-of-function mutant indicates that barbed-end binding is not necessary for oogenesis. Thus, increased nucleation is a critical element of synergy both in vitro and in vivo

Linear response separation of a solid into atomic constituents: Li, Al, and their evolution under pressure

We present the first realization of the generalized pseudoatom concept introduced by Ball, and adopt the name enatom to minimize confusion. This enatom, which consists of a unique decomposition of the total charge density (or potential) of any solid into a sum of overlapping atomiclike contributions that move rigidly with the nuclei to first order, is calculated using (numerical) linear response methods, and is analyzed for both fcc Li and Al at pressures of 0, 35, and 50 GPa. These two simple fcc metals (Li is fcc and a good superconductor in the 20-40 GPa range) show different physical behaviors under pressure, which reflects the increasing covalency in Li and the lack of it in Al. The nonrigid (deformation) parts of the enatom charge and potential have opposite signs in Li and Al; they become larger under pressure only in Li. These results establish a method of construction of the enatom, whose potential can be used to obtain a real-space understanding of the vibrational properties and electron-phonon interaction in solids.Comment: 13 pages, 9 figures, 1 table, V2: fixed problem with Fig. 7, V3: minor correction

User Identification and Authentication using Multi-Modal Behavioral Biometrics

Biometric computer authentication has an advantage over password and access card authentication in that it is based on something you are, which is not easily copied or stolen. One way of performing biometric computer authentication is to use behavioral tendencies associated with how a user interacts with the computer. However, behavioral biometric authentication accuracy rates are worse than more traditional authentication methods. This article presents a behavioral biometric system that fuses user data from keyboard, mouse, and Graphical User Interface (GUI) interactions. Combining the modalities results in a more accurate authentication decision based on a broader view of the user\u27s computer activity while requiring less user interaction to train the system than previous work. Testing over 31 users shows that fusion techniques significantly improve behavioral biometric authentication accuracy over single modalities on their own. Between the two fusion techniques presented, feature fusion and an ensemble based classification method, the ensemble method performs the best with a False Acceptance Rate (FAR) of 2.10% and a False Rejection Rate (FRR) 2.24%

Paths to Positivity: Relational Trajectories and Interaction in Positive Stepparent-Stepchild Dyads

Stepfamilies are inherently complex family systems, marked by change, flexible boundaries, and early conflict. But the developmental pathways by which long-term stepparent relationships become positive require more study. We interviewed 38 stepchildren who had reached adulthood, to understand how their relationships with a stepparent became positive. Four relational trajectories defined these positive relationships: punctuated, consistent positive, progressive incline, and modulated turbulent. Distinctive communicative practices were associated with each trajectory, such as communicating assurances, “siding,” or revelations of character. In addition, the trajectories shared three common processes: responsiveness to stepchild vulnerability, stepparent “adding value” to the family, and maturation/ reframing of the past. Findings support the existence of multiple pathways to positivity and suggest that major fluctuations are experienced along the way. Findings are interpreted in light of existing research on stepfamily development and Afifi’s theory of resilience and relational load. Recommendations are offered for stepfamilies and professionals who serve them

Sun-as-a-Star Spectrum Variations 1974-2006

We have observed selected Fraunhofer lines, both integrated over the Full Disk and for a small circular region near the center of the solar disk, on 1,215 days for the past 30 years. Full Disk results: Ca II K 393 nm nicely tracks the 11 year magnetic cycle based on sunspot number with a peak amplitude in central intensity of ~37%. The wavelength of the mid-line core absorption feature, called K3, referenced to nearby photospheric Fe, displays an activity cycle variation with an amplitude of 3 milli-Angstroms. Other chromospheric lines track Ca II K intensity with lower relative amplitudes. Low photosphere: Temperature sensitive CI 5380 nm appears constant in intensity to 0.2%. High photosphere: The cores of strong Fe I lines, Na D1 and D2, and the Mg I b lines, present a puzzling signal perhaps indicating a role for the 22 y Hale cycle. Solar minimum around 1985 was clearly seen, but the following minimum in 1996 was missing. This anomalous behavior is not seen in comparison atmospheric O2. Center Disk results: Both Ca II K and C I 538 nm intensities are constant, indicating that the basal quiet atmosphere is unaffected by cycle magnetism within our observational error. A lower limit to the Ca II K central intensity atmosphere is 0.040. The wavelength of Ca II K3 varies with the cycle by 6 milli-Angstroms, a factor of 2X over the full disk value. This may indicate the predominance of radial motions at Center Disk. This is not an effect of motions in plages since they are absent at Center Disk. This 11 y variation in the center of chromospheric lines could complicate the radial velocity detection of planets around solar-type stars. An appendix provides instructions for URL access to both the raw and reduced data.Comment: 38 pages with 20 figures. Accepted for publication in The Astrophysical Journa

Fermionic solution of the Andrews-Baxter-Forrester model II: proof of Melzer's polynomial identities

We compute the one-dimensional configuration sums of the ABF model using the fermionic technique introduced in part I of this paper. Combined with the results of Andrews, Baxter and Forrester, we find proof of polynomial identities for finitizations of the Virasoro characters $\chi_{b,a}^{(r-1,r)}(q)$ as conjectured by Melzer. In the thermodynamic limit these identities reproduce Rogers--Ramanujan type identities for the unitary minimal Virasoro characters, conjectured by the Stony Brook group. We also present a list of additional Virasoro character identities which follow from our proof of Melzer's identities and application of Bailey's lemma.Comment: 28 pages, Latex, 7 Postscript figure

Better the donor you know?:A qualitative study of renal patients' views on ‘altruistic’ live-donor kidney transplantation

AbstractBackgroundIn the UK there is a short-fall between individuals requiring a renal transplant and kidneys available for transplantation. Non-directed ‘altruistic’ living kidney donation has emerged as a strategy for bridging this gap between supply and demand, with the number increasing each year.ObjectiveThis study aimed to explore the views of potential recipients towards non-directed ‘altruistic’ live-donor kidney transplantation.MethodsSemi-structured interviews with 32 UK deceased-donor kidney transplant recipients were performed. Interviews explored willingness to consider directed and non-directed live-donor kidney transplants (LDKTs). Interviews were recorded, transcribed verbatim and transcripts were analysed using the constant comparison method described in Grounded Theory.ResultsFor those not willing to accept a non-directed ‘altruistic’ LDKT, the following themes were identified: i) Prioritising other recipients above self; ii) Fear of acquiring an unknown donor's characteristics, and iii) Concern for the donor – unnecessary risk. For those willing to accept a non-directed ‘altruistic’ LDKT the following themes were identified: iv) Prioritising known above unknown persons, v) Belief that they are as deserving as other potential recipients, and vi) Advantages of a LDKT.ConclusionsDrawing on ‘gift exchange theory’, this study contributes to our understanding of the experience of the intended recipient of a gift. The anonymity of the donor-recipient appears to be seen as a benefit of non-directed ‘altruistic’ live-donor transplants, freeing recipients from the obligations of the gift. However, those who feel unworthy of the ‘gifted transplant’ are concerned about the donor and by the lack of opportunity for direct reciprocity. Highlighting the ‘reciprocal benefits’ reported by donors may allow individuals whose preference is a live-donor transplant to accept one if offered. These insights provide the transplant community with targets for intervention, through which the concerns of potential recipients might be addressed

Subclinical infection of macaques and baboons with a baboon simarterivirus

Simarteriviruses (Arteriviridae: Simarterivirinae) are commonly found at high titers in the blood of African monkeys but do not cause overt disease in these hosts. In contrast, simarteriviruses cause severe disease in Asian macaques upon accidental or experimental transmission. Here, we sought to better understand the host-dependent drivers of simarterivirus pathogenesis by infecting olive baboons (n = 4) and rhesus monkeys (n = 4) with the simarterivirus Southwest baboon virus 1 (SWBV-1). Surprisingly, none of the animals in our study showed signs of disease following SWBV-1 inoculation. Three animals (two rhesus monkeys and one olive baboon) became infected and sustained high levels of SWBV-1 viremia for the duration of the study. The course of SWBV-1 infection was highly predictable: plasma viremia peaked between 1 × 107 and 1 × 108 vRNA copies/mL at 3–10 days post-inoculation, which was followed by a relative nadir and then establishment of a stable set-point between 1 × 106 and 1 × 107 vRNA copies/mL for the remainder of the study (56 days). We characterized cellular and antibody responses to SWBV-1 infection in these animals, demonstrating that macaques and baboons mount similar responses to SWBV-1 infection, yet these responses are ineffective at clearing SWBV-1 infection. SWBV-1 sequencing revealed the accumulation of non-synonymous mutations in a region of the genome that corresponds to an immunodominant epitope in the simarterivirus major envelope glycoprotein GP5, which likely contribute to viral persistence by enabling escape from host antibodies