bluuebunny/crossref_metadata_2025 huggingface dataset:
What's the Matter? Review of Derek Parfit, On What Matters
Authors: LANG GERALD
Published: May 2012

In the Preface to this enormous work, Derek Parfit makes a reference to Sidgwick's ‘great, drab book’ The Methods of Ethics (xxxiii). The juxtaposition of adjectives is amusing and oddly endearing; for Parfit, Sidgwick's drabness is not in any serious competition with his greatness. Parfit's two-volume book is not drab – though it can be exhausting – and, although it is probably too early to tell for sure, it also shows certain signs of greatness. Time and time again, one is impressed, even moved, by Parfit's enthralling and indefatigable resourcefulness and level of immersion in these issues, and by his dogged and transparently sincere commitment to discovering the truth about them. Despite its length, On What Matters demands careful study by everyone with a serious interest in philosophical ethics.
Neuropsychological Characteristics Associated with Olfactory Hallucinations in Schizophrenia
Authors: Arguedas Deborah , Langdon Robyn , Stevenson Richard
Published: May 2012

Olfactory hallucinations (OHs) are present in a significant minority of people with schizophrenia, yet these symptoms are under-researched and poorly understood. This study aimed to identify the neuropsychological impairments that associate with OHs in schizophrenia. Patients with schizophrenia or schizoaffective disorder were classified into an OH group and a group with auditory-verbal hallucinations (AVHs) and no lifetime history of OHs. Patients were age- and gender-matched to a healthy control group. All participants were assessed using: a test of odor identification; decision-making and socio-emotional tests of orbitofrontal cortex (OFC) and amygdala function; and a battery of standardized executive tests. Patients, as a whole, performed more poorly than controls on the tests of odor identification, emotion processing and executive function, consistent with previous research. Only two tests of OFC functioning: the Object Alternation Task, taken from Oscar-Berman and Zola-Morgan's (1980a, 1980b) Comparative Neuropsychological Tasks, and a test of “faux pas” understanding discriminated between the OH and AVH patients. Findings provide the first preliminary support for OH-specific neuropsychological impairments associated with OFC dysfunction in schizophrenia. (JINS, 2012,18, 1–10)
Mindfulness and psychosocial care in cancer: Historical context and review of current and potential applications
Authors: Greene Paul B. , Philip Errol J. , Poppito Shannon R. , Schnur Julie B.
Published: May 2012

Mindfulness-based interventions and mindfulness techniques have become increasingly popular in psychosocial care.  These interventions have also been increasingly used with cancer patients and survivors. However, more attention is due to issues such as how these techniques may be specifically relevant for an oncology population and whether the religious derivation of mindfulness should be considered by frontline psychosocial clinicians. This article provides a history and overview of the use of mindfulness in psychosocial cancer care.
The effects of L-NAME on neuronal NOS and SOD1 expression in the DRG–spinal cord network of axotomised Thy 1.2 eGFP mice
Authors: Bradman Matthew J. G. , Morris Richard , McArdle Anne , Jackson Malcolm J. , Thippeswamy Thimmasettappa
Published: May 2012

Nitric oxide (NO) plays an important role in pathophysiology of the nervous system. Copper/zinc superoxide dismutase (SOD1) reacts with superoxide, which is also a substrate for NO, to provide antioxidative protection. NO production is greatly altered following nerve injury, therefore we hypothesised that SOD1 and NO may be involved in modulating axotomy responses in dorsal root ganglion (DRG)–spinal network. To investigate this interaction, adult Thy1.2 enhanced membrane-bound green fluorescent protein (eGFP) mice underwent sciatic nerve axotomy and received NG-nitro- <l-arginine methylester (L-NAME) or vehicle 7–9 days later. L4–L6 spinal cord and DRG were harvested for immunohistochemical analyses. Effect of injury was confirmed by axotomy markers; small proline-rich repeat protein 1A (SPRR1A) was restricted to ipsilateral neuropathology, while Thy1.2 eGFP revealed also contralateral crossover effects. L-NAME, but not axotomy, increased neuronal NO synthase (nNOS) and SOD1 immunoreactive neurons, with no colocalisation, in a lamina-dependent manner in the dorsal horn of the spinal cord. Axotomy and/or L-NAME had no effect on total nNOS+and SOD1+neurons in DRG. However, L-NAME altered SOD1 expression in subsets of axotomised DRG neurons. These findings provide evidence for differential distribution of SOD1 and its modulation by NO, which may interact to regulate axotomy-induced changes in DRG–spinal network.
The use of a Cumulative Needs for Care Monitor for individual treatmentv. care as usual for patients diagnosed with severe mental illness, a cost-effectiveness analysis from the health care perspective
Authors: Drukker M. , Joore M. , van Os J. , Sytema S. , Driessen G. , Bak M. , Delespaul Ph.
Published: May 2012

Aims.

To study the systematic assessment of need for care and clinical parameters for use in treatment plans in patients diagnosed with severe mental illness.

Methods.

The Cumulative Needs for Care Monitor (CNCM) includes various validated instruments, such as the Camberwell Assessment of Need. A Markov-type cost-effectiveness model (health care perspective, 5-year time horizon) was used to compare CNCM with care as usual (CAU). Two studies were used to determine model parameters: a before–after study (n = 2155) and a matched-control study (n = 937).

Results.

The CNCM may lead to a gain in psychiatric functioning according to the models. CNCM patients remain in (outpatient) care, while CAU patients drop out more frequently. There is only a small difference in inpatient care. As a result, average costs per patient in the CNCM group are between €2809 (before–after model) and €5251 (matched-control model) higher. The iCER was between €45 127 and €57 839 per life year without psychiatric dysfunction gained.

Conclusions.

CNCM may be only cost-effective when willingness to pay for a life year without psychiatric dysfunction is higher than €45 000. However, this result is highly sensitive to the level of psychiatric dysfunctioning in patients who do not receive care.
Study of kinetic Alfvén wave and whistler wave spectra and their implication in solar wind plasma
Authors: Dwivedi Navin Kumar , Batra Karuna , Sharma R. P.
Published: May 2012

This work presents the numerical simulation of the nonlinear evolution of kinetic Alfvén wave (KAW), in a parametric regime consistent with the solar wind plasmas. The nonlinear dynamical equation of KAW satisfies the modified nonlinear Schrödinger equation when incident pump KAW has a small perturbation. Numerical simulation has been done to solve this model equation when the ponderomotive nonlinearity is incorporated in the KAW dynamics. The localization of pump KAW as a consequence of ponderomotive nonlinearity has been studied in the solar wind at 1 AU. A weak whistler signal propagating in these localized structures is amplified and leads to the development of its own localized structures. Magnetic power spectra and spectral indices for KAW at different times are calculated. The magnetic field power spectra and spectral indices of whistler wave at different times are also calculated. The relevance of steepened KAW and whistler spectra to recent solar wind observations is also pointed out. These localized structures and steeper spectra can be responsible for the plasma heating and particles acceleration in solar wind.
Isolating along‐strike variations in the depth extent of shallow creep and fault locking on the northern Great Sumatran Fault
Authors: Ito Takeo , Gunawan Endra , Kimata Fumiaki , Tabei Takao , Simons Mark , Meilano Irwan , Agustan  , Ohta Yusaku , Nurdin Irwandi , Sugiyanto Didik
Published: May 2012

The Great Sumatran Fault system in Indonesia is a major right‐lateral trench‐parallel system that can be divided into several segments, most of which have ruptured within the last century. This study focuses on the northern portion of the fault system which contains a 200‐km‐long segment that has not experienced a major earthquake in at least 170 years. In 2005, we established the Aceh GPS Network for the Sumatran Fault System (AGNeSS) across this segment. AGNeSS observes large displacements which include significant postseismic deformation from recent large megathrust earthquakes as well as interseismic deformation due to continued elastic loading of both the megathrust and the strike slip system. We parameterize the displacements due to afterslip on the megathrust using a model based on a rate‐ and state‐dependent friction formalism. Using this approach, we are able to separate afterslip from other contributions. We remove predicted deformation due to afterslip from the observations, and use these corrected time series to infer the depth of shallow aseismic creep and deeper locked segments for the Great Sumatran Fault. In the northern portion of this fault segment, we infer aseismic creep down to 7.3 ± 4.8 km depth at a rate of 2.0 ± 0.6 cm/year. In the southwestern portion of the segment, we estimate a locking depth of 14.8 ± 3.4 km with a downdip slip rate of 1.6 ± 0.6 cm/year. This portion of the fault is capable of producing a magnitude 7.0 earthquake.
Evaluation of nonlocal and local planetary boundary layer schemes in the WRF model
Authors: Xie Bo , Fung Jimmy C. H. , Chan Allen , Lau Alexis
Published: May 2012

A realistic reproduction of planetary boundary layer (PBL) structure and its evolution is critical to numerical simulation of regional meteorology and air quality. Conversely, insufficient realism in the simulated physical properties often leads to degraded meteorological and air quality prognostic skills. This study employed the Weather Research and Forecasting model (WRF) to evaluate model performance and to quantify meteorological prediction differences produced by four widely used PBL schemes. Evaluated were two nonlocal PBL schemes, YSU and ACM2, and two local PBL schemes, MYJ and Boulac. The model grid comprised four nested domains at horizontal resolutions of 27 km, 9 km, 3 km and 1 km respectively. Simulated surface variables 2 m temperature and 10 m wind at 1 km resolution were compared to measurements collected in Hong Kong. A detailed analysis of land‐atmosphere energy balance explicates heat flux and temperature variability among the PBL schemes. Differences in vertical profiles of horizontal velocity, potential temperature, bulk Richardson number and water vapor mixing ratio were examined. Diagnosed PBL heights, estimated by scheme specific formulations, exhibited the large intrascheme variance. To eliminate formulation dependence in PBL height estimation, lidar measurements and a unified diagnosis were jointly used to reanalyze PBL heights. The diagnosis showed that local PBL schemes produced shallower PBL heights than those of nonlocal PBL schemes. It is reasonable to infer that WRF, coupled with the ACM2 PBL physics option can be a viable producer of meteorological forcing to regional air quality modeling in the Pearl River Delta (PRD) Region.
Tectono‐stratigraphic signature of multiphased rifting on divergent margins (deep‐offshore southwest Iberia, North Atlantic)
Authors: Pereira Ricardo , Alves Tiago M.
Published: May 2012

Regional 2D multichannel seismic, borehole, dredge and outcrop data, together with burial models for strata in southwest Iberia, are used to investigate the tectono‐stratigraphic signature of multiphased rifting on divergent margins. Our burial model reveals that Mesozoic extension occurred during three main phases, each comprising distinct subsidence pulses separated by short‐lived periods of crustal uplift. The importance of the three phases varies across discrete sectors of the margin, each one revealing similar depositional architectures and associated tectonic systems tracts: 1) the Rift Initiation phase, characterized by incipient subsidence and overall aggradation/progradation over a basal unconformity, 2) the Rift Climax phase, which marks maxima of tectonic subsidence and is characterized by retrogradation‐progradation, and 3) the Late Rift phase, recording the progradational infill of the basin and the effects of eustasy. The Rift Initiation systems tracts comprise Sinemurian and late Callovian‐early Oxfordian strata. Marine units in the Pliensbachian and Late Oxfordian‐Kimmeridgian represent the Rift Climax phase, a period marked by the development of Maximum Flooding Surfaces. Late Rift deposits were identified in the Rhaetian‐Hettangian, Toarcian‐Bathonian and Kimmeridgian‐Berriasian. The results of this work are important to the economic exploration of deep‐offshore rift basins, as they reveal that sequence stratigraphy can be used to predict sedimentary facies distribution in more distal segments of such basins. Significantly, this work recognizes that multiple tectonic‐stratigraphic (rift) cycles can occur on deep‐offshore rift basins, from the onset of rift‐related extension until continental break‐up, a character that contrast to what is known from deep‐sea drilling data from the distal margin of Northwest Iberia.
Coseismic velocity change in and around the focal region of the 2008 Iwate‐Miyagi Nairiku earthquake
Authors: Takagi Ryota , Okada Tomomi , Nakahara Hisashi , Umino Norihito , Hasegawa Akira
Published: May 2012

The 2008 M7.2 Iwate‐Miyagi Nairiku earthquake occurred in NE Japan where dense seismic networks exist. Using the data from these networks, we determined the coseismic seismic velocity change associated with this earthquake by two different methods: ambient noise interferometry and vertical array interferometry of coda wave. The purpose of this article is to reveal the spatial distribution and the cause of the velocity change by integrating these two approaches. Ambient noise interferometry revealed a coseismic velocity decrease of Rayleigh wave by 0.1–0.5% at 0.25–0.5 Hz. We also estimated the spatial distribution of the velocity change by a tomographic inversion. The velocity decrease was distributed in and around the focal area. In the second method, we applied cross‐correlation analysis to coda waves observed by the KiK‐net vertical array. We detected a shear velocity decrease of approximately 5% in shallow layers up to a few hundred meters depth. Quantitative comparison of the two results reveals that the 5% shear velocity decrease in shallow layers can explain the 0.1–0.5% decrease of Rayleigh wave velocity. The distribution of the velocity decrease is similar to that of the strong ground motion and the static stress change. However, a significant velocity increase is not observed in the compression area, where a velocity increase is expected. Based on the observations, we consider that the primary factor affecting the velocity change is damage in shallow layers due to strong motion. The effect of the static stress change might be masked by the larger effect of the strong motion.
Contribution of tropical cyclones to stratosphere‐troposphere exchange over the northwest Pacific: Estimation based on AIRS satellite retrievals and ERA‐Interim data
Authors: Zhan Ruifen , Wang Yuqing
Published: May 2012

Deep convection associated with tropical cyclones (TCs) is considered to play an important role in the tropical troposphere‐to‐stratosphere transport (TST). In this study, both the AIRS satellite measurements on Aqua and the Interim reanalysis of the European Centre for Medium‐Range Weather Forecasts (ERA‐Interim) are used to estimate the contribution of TCs to the tropical TST over the western North Pacific (WNP). A case study for Typhoon Nock‐ten (2004) demonstrates that both the AIRS and the ERA‐Interim data can infer the direct transport of the tropospheric air into the lower stratosphere in the vicinity of the TC eyewall. A contrast analysis for the inactive and active TC seasons of 2003 and 2004 over the WNP based on the same data sets suggests that in the region where TCs occur frequently the TST is significantly enhanced. As a result, the TC‐induced TST in the active TC season is about 25% higher than that in the inactive TC season. The results based on the ERA‐Interim data for the TC seasons over the WNP from 1989 to 2010 show that TCs can account for more than 10% of the total TST in most of the impact region with the highest contribution up to 30%. Over the entire WNP, TCs account for about 5.6% of the total TST and about 10.9% of the total upward transport across the base of the Tropical Transition Layer (TTL). This suggests that TCs could have a significant contribution to the total upward transport into the TTL over the WNP.
Biomarkers of Neuroglial Injury in Rat Models of Combat TBI: Primary Blast Over-Pressure Compared to “Composite” Blast
Authors: Svetlov Stanislav I. , Prima Victor , Glushakova Olena , Svetlov Artem , Kirk Daniel R. , Gutierrez Hector , Wang Kevin K. W. , Hayes Ronald L.
Published: May 2012

A number of experimental models of blast brain injury have been implemented in rodents and larger animals. However, the variety of blast sources and the complexity of blast wave biophysics have made data on injury mechanisms and biomarkers difficult to analyze and compare. Recently, we showed the importance of rat position towards blasts generated by an external shock tube.

In this study, we further characterized blasts producing moderate traumatic brain injury (TBI) and defined “composite” blast and primary blast exposure setups. Schlieren optics visualized interaction between the head and a shock wave generated by an external shock tube, revealing strong head acceleration upon positioning the rat on-axis with the shock tube (composite blast), but negligible skull movement upon peak over-pressure exposure off-axis (primary blast). Brain injury signatures of a primary blast hitting the frontal head were assessed and compared to damage produced by composite blast. Low to negligible levels of neurodegeneration were found following primary blast compared to composite blast by silver staining. However, persistent gliosis in the hippocampus and accumulation of GFAP/CNPase in the circulation was detected after both primary and composite blasts.

In conclusion, neuro-glial biomarkers of brain injury were elevated at all blast setups. The most significant and persistent changes in neuronal markers were found after composite blast, while astrocyte and oligodendrocyte biomarkers GFAP and CNPase were up-regulated following both composite and primary blast exposure.
Molecular Dynamics Structure Prediction of a Novel Protein–DNA Complex: Two HU Proteins with a DNA Four-way Junction
Authors: Wheatley Elizabeth G. , Pieniazek Susan N. , Vitoc Iulia , Mukerji Ishita , Beveridge D.L.
Published: May 2012

The DNA four-way junction (4WJ) is a non-canonical structure of DNA that is involved in homologous replication and recombination. There are essentially two forms of 4WJ in solution, an open form (OPN) characterized in a square plane configuration by a mobile center and four duplex arms, and a stacked-X form (STX), with two pseudo-duplex strands stacked on top of one another and intersecting at the positions of strand exchange. The prokaryotic architectural protein HU is known to bind damaged or nicked duplex DNA as well as the STX form of the 4WJ with nanomolar affinity. Recent spectroscopic studies demonstrated that the stoichiometric ratio of HU:4WJ in the complex is 2:1, but the molecular structure of the complex has not been determined. A set of distances within the complex have been obtained using Förster resonance energy transfer (FRET) but the results are insufficient to provide details of the location and orientation of the proteins with respect to the DNA. In this project, we have constructed a series of possible models for the 2HU-4WJ complex using computer graphics, docking, energy minimization, and all-atom molecular dynamics (MD) simulation including explicit solvent. Three models with the proteins situated in various orientations were investigated in detail. A structure with the two HU proteins docked in a face-to-face orientation across the junction provided the closest overall agreement between calculated and observed FRET results. This structure was dynamically stable over the course of 30ns of MD simulation.
Computer-aided Drug Discovery: Two Antiviral Drugs for HIV/AIDS
Authors: Andrew McCammon J.
Published: May 2012

Computational, structure-based methods developed in the author's group have contributed to the discovery of two antiviral drugs that are effective in the treatment of HIV/AIDS. A brief account of this work is presented.
Acceptance and Commitment Therapy for People Who Stutter
Authors: Beilby Janet M. , Byrnes Michelle L.
Published: May 2012

In contemporary clinical allied health and medical settings, there has been a proliferation of Acceptance and Commitment Therapy (ACT) programs. These clinically effective programs have reduced comorbid anxiety, depression, and stress for individuals suffering from chronic medical and psychosocial issues. However, to date, there has been no published work examining the effectiveness of an integrated ACT program for individuals who stutter. In this review, we will provide a platform from which readers will be able to (a) appraise the literature regarding combined speech pathology and psychology therapeutic programs for people who stutter, (b) appreciate an overview of ACT in the context of stuttering disorders, and (c) understand the relevant psychosocial outcome measures that constitute therapeutic change. This unique review of ACT will distinguish the processes of self-concept, defusion, acceptance, mindfulness, values, and committed action in support for people who stutter who experience psychosocial distress. In the culmination of the review, we advance the integration of ACT into current treatments for individuals who stutter.
A Preliminary Report on Outcomes of the American Institute for Stuttering Intensive Therapy Program
Authors: Pollard Ryan
Published: May 2012

In this study, we documented the effects of a 3-week, intensive stuttering treatment program on overt and covert symptoms of stuttering and participants’ levels of social anxiety. This study was a preliminary report in which we used a single-group pretest-posttest design to analyze outcomes data with reference to each participant individually and described general group trends. Researchers gave 5 adult participants who stuttered a battery of self-report instruments and collected speech samples before and after treatment. We found that disfluencies lessened considerably for all participants, although most continued to stutter at levels above those of normally fluent speakers. All participants except for 1 were far less negatively affected by stuttering after treatment and greatly reduced their reported levels of social anxiety. Several participants in this sample displayed pathological levels of social anxiety pretreatment. Preliminary data indicate that this intensive program generally achieved its stated goals of facilitating improved stuttering/speech management and psychological/attitudinal management. We need further investigations to document the durability of the gains reported herein, as well as the clinical implications of social anxiety as a comorbid condition in some persons who stutter.
The Walsham Hotel: The Mechatronic KoolNitro 346 Mini-bar
Authors: Adams Dennis A , Ives Blake , Junglas Iris
Published: May 2012

The Walsham hotel is an upscale hotel, located in a large southern city. Its clientele have high expectations and, given the Walsham's urban location, likely includes many senior executives. The case focuses on the hotel's Director of Rooms and, in particular, the hotel's profitable mini-bar department. A major face-lift for the property's rooms provides an opportunity to replace the refrigeration units in the mini-bar, units that have been in place for over 10 years. The Director is considering either a more energy-efficient version of the current unit or a much more expensive unit, the KN346. The latter has some interesting electronic features including sensing technology and peer-to-peer networking that, together, would permit remote real-time access to the mini-bar inventory. This unit could drive down labor costs, reduce disagreements at check-out, improve customer service, and allow personalized mini-bar stocking. The case is arranged in four parts. Only Part A should be distributed in advance. Part B should be distributed only after Part A is discussed. Parts C and D could be similarly distributed only after discussion of their preceding parts.
Effects of substrate strain and electrical stress on lattice dynamics, defects, and traps in strained-Si/Si0.81Ge0.19 n-type metal-oxide-semiconductor field effect transistors
Authors: Mukherjee C. , Sengupta S. , Maiti C. K. , Maiti T. K.
Published: May 2012

Defects and traps in strained-Si n-type metal-oxide-semiconductor field effect transistors (MOSFETs) are studied in detail. The inelastic electron tunneling spectroscopy (IETS) technique is shown to be capable of probing traps in ultrathin gate dielectrics and obtain the energies and spatial locations of the traps. Detailed analyses of electrical stress-induced build-up of traps and electrically active bonding defects and identification of the trap-features including trap-assisted conduction and charge-trapping have been performed. The location and energies of the traps are estimated from the IETS spectra measured at both bias polarities. Identification of the acoustic and optical phonon modes (inelastic) as well as trap-features (elastic) helps in better understandings of the complex transport-mechanisms in gate dielectrics on strained layers.
Parametric optomechanical oscillations in two-dimensional slot-type high-Q photonic crystal cavities
Authors: Zheng Jiangjun , Li Ying , Sirin Aras Mehmet , Stein Aaron , Shepard Ken L. , Wei Wong Chee
Published: May 2012

We experimentally demonstrate an optomechanical cavity based on an air-slot photonic crystal cavity with optical quality factor Qo = 4.2 × 104 and a small modal volume of 0.05 cubic wavelengths. The optical mode is coupled with the in-plane mechanical modes with frequencies up to hundreds of MHz. The fundamental mechanical mode shows a frequency of 65 MHz and a mechanical quality factor of 376. The optical spring effect, optical damping, and amplification are observed with a large experimental optomechanical coupling rate gom/2π of 154 GHz/nm, corresponding to a vacuum optomechanical coupling rate g*/2π of 707 kHz. With sub-mW or less input power levels, the cavity exhibits strong parametric oscillations. The phase noise of the photonic crystal optomechanical oscillator is also measured.
Modeling technique of capacitive discharge pumping of metal vapor lasers for electrode capacitance optimization
Authors: Gubarev F. A. , Evtushenko G. S. , Vuchkov N. K. , Sukhanov V. B. , Shiyanov D. V.
Published: May 2012

To estimate optimum gas discharge tube (GDT) electrode capacitance of metal vapor lasers (MVLs) pumped by a longitudinal capacitive discharge, we offer to use series connection of capacitors to the electrodes of a conventionally pumped GDT with inner electrodes. It has been demonstrated that the maximum output power in CuBr lasers is obtained when the capacitances of high-voltage and ground electrodes are equal. When using a model circuit an average output power reaches 12 W that suggests the possibility of generating high average output power (>10 W) in MVLs pumped using a capacitive discharge.
Enhanced thermoelectric figure-of-merit ZT for hole-doped Bi2Sr2Co2Oy through Pb substitution
Authors: Hsu H. C. , Lee W. L. , Wu K. K. , Kuo Y. K. , Chen B. H. , Chou F. C.
Published: May 2012

Single crystals of Bi2–xPbxSr2Co2Oy (0 ≤ x ≤ 0.55) have been grown using optical floating-zone method. The chemical compositions were determined using combined electron probe microanalysis and iodometric titration. Physical properties including electrical resistivity (ρ), Seebeck coefficient (S), and thermal conductivity (κ) were measured using single crystal specimens. Successful hole doping through Pb substitution is confirmed through combined iodometry titration, electrical transport, and Seebeck coefficient measurements. Significant reduction on both in-plane resistivity and thermal conductivity was found as a result of Pb substitution to the Bi site. The thermoelectric figure-of-merit ZT for x ∼ 0.55 is raised 20 folds from the undoped sample at room temperature.
Demonstration of shortwavelength infrared photodiodes based on type-II InAs/GaSb/AlSb superlattices
Authors: Hoang A. M. , Chen G. , Haddadi A. , Abdollahi Pour S. , Razeghi M.
Published: May 2012

We demonstrate the feasibility of the InAs/GaSb/AlSb type-II superlattice photodiodes operating at the short wavelength infrared regime below 3 μm. An n-i-p type-II InAs/GaSb/AlSb photodiode was grown with a designed cut-off wavelength of 2 μm on a GaSb substrate. At 150 K, the photodiode exhibited a dark current density of 5.6 × 10−8 A/cm2 and a front-side-illuminated quantum efficiency of 40.3%, providing an associated shot noise detectivity of 1.0 × 1013 Jones. The uncooled photodiode showed a dark current density of 2.2 × 10−3 A/cm2 and a quantum efficiency of 41.5%, resulting in a detectivity of 1.7 × 1010 Jones.
Electrostatically driven collapsible Au thin films assembled using transfer printing for thermal switching
Authors: Keum Hohyun , Seong Myunghoon , Sinha Sanjiv , Kim Seok
Published: May 2012

We report deterministic assembly of 100 nm thick suspended gold films using transfer printing that are mechanically collapsible. We demonstrate the latter using electrostatic force to establish and break physical contact between the film and a silicon dioxide substrate in a reversible and repeatable manner. Modeling the thermal conductance at the interface between the suspended film and the substrate, we show that the fabricated structure behaves as a thermal switch. The on-state corresponds to the collapsed film and the off-state to the fully suspended film. The on- to off-state ratio for thermal conductance exceeds 106 in theory.
Spin splitting in bulk wurtzite AlN under biaxial strain
Authors: Kao Hsiu-Fen , Lo Ikai , Chiang Jih-Chen , Lee Meng-En , Wu C. L. , Wang W. T. , Chen Chun-Nan , Hsu Y. C.
Published: May 2012

The spin-splitting energies in biaxially strained bulk wurtzite material AlN are calculated using the linear combination of atomic orbital (LCAO) method, and the equi-spin-splitting distributions in k-space near the minimum-spin-splitting (MSS) surfaces are illustrated. These data are compared with those derived analytically by two-band k · p (2KP) model. It is found that the results from these two methods are in good agreement for small k. However, the ellipsoidal MSS surface under biaxial compressive strain does not exist in the 2KP model, because the data points are far from the Γ point. Instead, three basic shapes of the MSS surface occur in the wurtzite Brillouin zone: a hyperboloid of two sheets, a hexagonal cone, and a hyperboloid of one sheet, evaluated from the LCAO method across the range of biaxial strains from compressive to tensile.
Nonvolatile organic write-once-read-many-times memory devices based on hexadecafluoro-copper-phthalocyanine
Authors: Wang Lidan , Su Zisheng , Wang Cheng
Published: May 2012

Nonvolatile organic write-once-read-many-times memory device was demonstrated based on hexadecafluoro-copper-phthalocyanine (F16CuPc) single layer sandwiched between indium tin oxide (ITO) anode and Al cathode. The as fabricated device remains in ON state and it can be tuned to OFF state by applying a reverse bias. The ON/OFF current ratio of the device can reach up to 2.3 × 103. Simultaneously, the device shows long-term storage stability and long retention time in air. The ON/OFF transition is attributed to the formation and destruction of the interfacial dipole layer in the ITO/F16CuPc interface, and such a mechanism is different from previously reported ones.
Exciton confinement and trapping dynamics in double-graded-bandgap quantum nanowires
Authors: Szeszko J. , Belykh V. V. , Gallo P. , Rudra A. , Karlsson K. F. , Sibeldin N. N. , Kapon E.
Published: May 2012

We fabricate and study quantum dot structures incorporating quasi-one-dimensional excited states. The structures are realized by graded bandgap GaAs/AlGaAs quantum wires self-formed inside inverted tetrahedral pyramids. The ground state transitions exhibit typical characteristics of fully confined excitons, including single photon emission. Efficient carrier thermalization and relaxation, as well as correlated photon emission is observed also among the excited states, indicating the formation of quasi-one-dimensional multi-exciton states. These structures offer interesting possibilities for collecting and directing charge carriers towards heterostructured potential traps.
Self-assembled formation and transformation of In/CdZnTe(110) nano-rings into camel-humps
Authors: Cohen-Taguri G. , Ruzin A. , Goldfarb I.
Published: May 2012

We used in situ scanning tunneling microscopy to monitor in real time the formation of nano-rings at the molecular beam epitaxially grown In/CdZnTe(110) surface, and Auger electron spectroscopy to explore the corresponding compositional changes. In-diffusion of In and segregation of Cd to the surface in course of annealing lead to a formation of elliptically distorted nano-rings, elongated along the fast [1¯10] diffusion direction. Exacerbated diffusion anisotropy in the liquid state, at temperatures above the melting point of In, further distorts the nano-rings into a camel-hump shape.
Electrodiffusion of lipids on membrane surfaces
Authors: Zhou Y. C.
Published: May 2012

Lateral translocation of lipids and proteins is a universal process on membrane surfaces. Local aggregation or organization of lipids and proteins can be induced when the random lateral motion is mediated by the electrostatic interactions and membrane curvature. Although the lateral diffusion rates of lipids on membranes of various compositions are measured and the electrostatic free energies of predetermined protein-membrane-lipid systems can be computed, the process of the aggregation and the evolution to the electrostatically favorable states remain largely undetermined. Here we propose an electrodiffusion model, based on the variational principle of the free energy functional, for the self-consistent lateral drift-diffusion of multiple species of charged lipids on membrane surfaces. Finite sizes of lipids are modeled to enforce the geometrical constraint of the lipid concentration on membrane surfaces. A surface finite element method is developed to appropriate the Laplace-Beltrami operators in the partial differential equations of the model. Our model properly describes the saturation of lipids on membrane surfaces, and correctly predicts that the MARCKS peptide can consistently sequester three multivalent phosphatidylinositol 4,5-bisphosphate lipids through its basic amino acid residues, regardless of a wide range of the percentage of monovalent phosphatidylserine in the membrane.
Biased internal potential distributions in a bulk-heterojunction organic solar cell incorporated with a TiOx interlayer
Authors: Kong Jaemin , Lee Jongjin , Jeong Yonkil , Kim Maengjun , Kang Sung-Oong , Lee Kwanghee
Published: May 2012

External-biased potential distributions of a polymer bulk-heterojunction (BHJ) solar cell, incorporated with electron/hole transporting layers, were directly obseved through a cross-sectional Kelvin probe force microscopy. The bulk electric field of BHJ was found to be nearly field-free even under reverse biases, and the field-free region was probed to expand with the incorporation of TiOx electron transporting layer; as a result, inducing a decrease of quasi-Fermi level splitting region in obtaining a high fill factor in the TiOx-interlayered junction photodiodes.
Flexoelectric coefficient measurements in the nematic liquid crystal phase of 5CB
Authors: Castles F. , Green S. C. , Gardiner D. J. , Morris S. M. , Coles H. J.
Published: May 2012

We report measurements of the bulk flexoelectric coefficient (e1 − e3) of 5CB (4-Cyano-4′-pentylbiphenyl), in the temperature range 20–34 °C, with a relative combined standard uncertainty of 2 %. The chiral flexoelectro-optic method was used with 1 wt % high-twisting-power chiral additive. At 25 °C, (e1 − e3) = 7.10 pC/m with a combined standard uncertainty of 0.14 pC/m.
Australian maternity reform through clinical redesign
Authors: Hartz Donna L. , White Jan , Lainchbury Kathleen A. , Gunn Helen , Jarman Helen , Welsh Alec W. , Challis Daniel , Tracy Sally K.
Published: May 2012

The current Australian national maternity reform agenda focuses on improving access to maternity care for women and their families while preserving safety and quality. The caseload midwifery model of care offers the level of access to continuity of care proposed in the reforms however the introduction of these models in Australia continues to meet with strong resistance. In many places access to caseload midwifery care is offered as a token, usually restricted to well women, within limited metropolitan and regional facilities and where available, places for women are very small as a proportion of the total service provided. This case study outlines a major clinical redesign of midwifery care at a metropolitan tertiary referral maternity hospital in Sydney. Caseload midwifery care was introduced under randomised trial conditions to provide midwifery care to 1500 women of all risk resulting in half of the publicly insured women receiving midwifery group practice care. The paper describes the organisational quality and safety tools that were utilised to facilitate the process while discussing the factors that facilitated the process and the barriers that were encountered within the workforce, operational and political context. What is known about the topic? Caseload midwifery models of care have been established in a variety of community based and hospital settings throughout Australia with a reported reduction in clinical intervention rates while maintainning safety of mothers and babies. What does this paper add? This case study illustrates the strategies used to achieve a large sustainable clinical service redesign project based on the introduction of the caseload midwifery model of care. What are the implications for practitioners? Establishing midwifery group practice care within the mainstream maternity services has far reaching implications for the retention and recruitment of midwives and the improvement of clinical outcomes in childbirth.
Leadership collaboration during health reform: an action learning approach with an interagency group of executives in Tasmania
Authors: Harpur Siobhan
Published: May 2012

Objective. To use an action learning approach to encourage a group of executive leaders, responsible for the implementation of a state health reform agenda, to consider the leadership required to drive improvement in healthcare services. Methods. Based on an assertion that knowledge is co-produced and that deliberative and structured conversation can be a mechanism to drive change, an action learning approach was used to facilitate an interagency group of executive leaders, responsible for the implementation of a state health reform agenda, who were encouraged to consider the leadership required to drive improvement in healthcare services. Results. It was difficult to assert how the group contributed specifically to the implementation of the health reform agenda but individuals gained insights and there was informal resolution of institutional tensions and differences. The method may provide new knowledge to the reform process over time. Conclusions. Getting the participants together was challenging, which may reflect the reality of time-poor executives, or a low commitment to giving time to structured and deliberative informal dialogue. Further work is required to test this thesis and the action learning approach with other parts of healthcare workforce.
Magnetic stripes and skyrmions with helicity reversals
Authors: Yu Xiuzhen , Mostovoy Maxim , Tokunaga Yusuke , Zhang Weizhu , Kimoto Koji , Matsui Yoshio , Kaneko Yoshio , Nagaosa Naoto , Tokura Yoshinori
Published: May 2012

It was recently realized that topological spin textures do not merely have mathematical beauty but can also give rise to unique functionalities of magnetic materials. An example is the skyrmion—a nano-sized bundle of noncoplanar spins—that by virtue of its nontrivial topology acts as a flux of magnetic field on spin-polarized electrons. Lorentz transmission electron microscopy recently emerged as a powerful tool for direct visualization of skyrmions in noncentrosymmetric helimagnets. Topologically, skyrmions are equivalent to magnetic bubbles (cylindrical domains) in ferromagnetic thin films, which were extensively explored in the 1970s for data storage applications. In this study we use Lorentz microscopy to image magnetic domain patterns in the prototypical magnetic oxide–M-type hexaferrite with a hint of scandium. Surprisingly, we find that the magnetic bubbles and stripes in the hexaferrite have a much more complex structure than the skyrmions and spirals in helimagnets, which we associate with the new degree of freedom—helicity (or vector spin chirality) describing the direction of spin rotation across the domain walls. We observe numerous random reversals of helicity in the stripe domain state. Random helicity of cylindrical domain walls coexists with the positional order of magnetic bubbles in a triangular lattice. Most unexpectedly, we observe regular helicity reversals inside skyrmions with an unusual multiple-ring structure.
Full-length axon regeneration in the adult mouse optic nerve and partial recovery of simple visual behaviors
Authors: de Lima Silmara , Koriyama Yoshiki , Kurimoto Takuji , Oliveira Julia Teixeira , Yin Yuqin , Li Yiqing , Gilbert Hui-Ya , Fagiolini Michela , Martinez Ana Maria Blanco , Benowitz Larry
Published: May 2012

The mature optic nerve cannot regenerate when injured, leaving victims of traumatic nerve damage or diseases such as glaucoma with irreversible visual losses. Recent studies have identified ways to stimulate retinal ganglion cells to regenerate axons part-way through the optic nerve, but it remains unknown whether mature axons can reenter the brain, navigate to appropriate target areas, or restore vision. We show here that with adequate stimulation, retinal ganglion cells are able to regenerate axons the full length of the visual pathway and on into the lateral geniculate nucleus, superior colliculus, and other visual centers. Regeneration partially restores the optomotor response, depth perception, and circadian photoentrainment, demonstrating the feasibility of reconstructing central circuitry for vision after optic nerve damage in mature mammals.
Molecular signaling network complexity is correlated with cancer patient survivability
Authors: Breitkreutz Dylan , Hlatky Lynn , Rietman Edward , Tuszynski Jack A.
Published: May 2012

The 5-y survival for cancer patients after diagnosis and treatment is strongly dependent on tumor type. Prostate cancer patients have a >99% chance of survival past 5 y after diagnosis, and pancreatic patients have <6% chance of survival past 5 y. Because each cancer type has its own molecular signaling network, we asked if there are “signatures” embedded in these networks that inform us as to the 5-y survival. In other words, are there statistical metrics of the network that correlate with survival? Furthermore, if there are, can such signatures provide clues to selecting new therapeutic targets? From the Kyoto Encyclopedia of Genes and Genomes Cancer Pathway database we computed several conventional and some less conventional network statistics. In particular we found a correlation (
R
2
= 0.7) between degree-entropy and 5-y survival based on the Surveillance Epidemiology and End Results database. This correlation suggests that cancers that have a more complex molecular pathway are more refractory than those with less complex molecular pathway. We also found potential new molecular targets for drugs by computing the betweenness—a statistical metric of the centrality of a node—for the molecular networks.
Nanoelectrodes for determination of reactive oxygen and nitrogen species inside murine macrophages
Authors: Wang Yixian , Noël Jean-Marc , Velmurugan Jeyavel , Nogala Wojciech , Mirkin Michael V. , Lu Cong , Guille Collignon Manon , Lemaître Frédéric , Amatore Christian
Published: May 2012

Reactive oxygen and nitrogen species (ROS and RNS) produced by macrophages are essential for protecting a human body against bacteria and viruses. Micrometer-sized electrodes coated with Pt black have previously been used for selective and sensitive detection of ROS and RNS in biological systems. To determine ROS and RNS inside macrophages, one needs smaller (i.e., nanometer-sized) sensors. In this article, the methodologies have been extended to the fabrication and characterization of Pt/Pt black nanoelectrodes. Electrodes with the metal surface flush with glass insulator, most suitable for quantitative voltammetric experiments, were fabricated by electrodeposition of Pt black inside an etched nanocavity under the atomic force microscope control. Despite a nanometer-scale radius, the true surface area of Pt electrodes was sufficiently large to yield stable and reproducible responses to ROS and RNS in vitro. The prepared nanoprobes were used to penetrate cells and detect ROS and RNS inside macrophages. Weak and very short leaks of ROS/RNS from the vacuoles into the cytoplasm were detected, which a macrophage is equipped to clean within a couple of seconds, while higher intensity oxidative bursts due to the emptying of vacuoles outside persist on the time scale of tens of seconds.
Amorphous diamond-structured photonic crystal in the feather barbs of the scarlet macaw
Authors: Yin Haiwei , Dong Biqin , Liu Xiaohan , Zhan Tianrong , Shi Lei , Zi Jian , Yablonovitch Eli
Published: May 2012

Noniridescent coloration by the spongy keratin in parrot feather barbs has fascinated scientists. Nonetheless, its ultimate origin remains as yet unanswered, and a quantitative structural and optical description is still lacking. Here we report on structural and optical characterizations and numerical simulations of the blue feather barbs of the scarlet macaw. We found that the sponge in the feather barbs is an amorphous diamond-structured photonic crystal with only short-range order. It possesses an isotropic photonic pseudogap that is ultimately responsible for the brilliant noniridescent coloration. We further unravel an ingenious structural optimization for attaining maximum coloration apparently resulting from natural evolution. Upon increasing the material refractive index above the level provided by nature, there is an interesting transition from a photonic pseudogap to a complete bandgap.