Optical Interferometry with Quantum Networks.

We propose a method for optical interferometry in telescope arrays assisted by quantum networks. In our approach, the quantum state of incoming photons along with an arrival time index are stored in a binary qubit code at each receiver. Nonlocal retrieval of the quantum state via entanglement-assisted parity checks at the expected photon arrival rate allows for direct extraction of the phase difference, effectively circumventing transmission losses between nodes. Compared to prior proposals, our scheme (based on efficient quantum data compression) offers an exponential decrease in required entanglement bandwidth. Experimental implementation is then feasible with near-term technology, enabling optical imaging of astronomical objects akin to well-established radio interferometers and pushing resolution beyond what is practically achievable classically.

Ultrasound-guided breast-conserving surgery for early-stage palpable and nonpalpable invasive breast cancer: decreased excision volume at unchanged tumor-free resection margin.

Ultrasound guidance (USG) during breast-conserving surgery improves tumor-free surgical resection margins. The objective of this study was to evaluate whether USG reduces resection volumes without compromising margin status. 134 patients with palpable or nonpalpable T1-2N0-1 invasive breast cancer were treated with USG and compared with a historical reference control group (CON) consisting of palpation-guided (PAG) or wire-guided localization (WIG) breast-conserving surgery. Primary outcomes were excess resection volume and clear margin status, and secondary outcome was re-excision rate. 66 patients underwent USG. In the CON group (n = 68), PAG was performed in 24 (35 %) and WIG in 44 (64 %) patients. Median excision volume [39 (IQR 20-66) vs 56 (38-94) cm(3); p = 0.001] and median calculated resection ratio [1.7 (1.0-2.9) vs 2.8 (1.4-4.6) (p = 0.005)] were significantly smaller in the USG than in the CON group. Median minimal distance to the resection margin [4 mm (IQR 2-5 mm) vs 2 mm (1-4 mm), p = 0.004] was significantly larger. Clear resection margins were achieved in 58 of the USG patients (88 %) and in 58 of the CON patients (86 %) (p = 0.91); this was true in patients with palpable as well as nonpalpable lesions. Reexcision was needed in 6.1 and 7.2 % respectively. Relative risk for re-excision in the USG group was 0.82 (95 % CI 0.23-2.93). In patients with palpable and nonpalpable breast cancers, USG allows for lower excision volume and reduced resection of healthy breast tissue, without increased re-excision rate.

Nuclear magnetic resonance detection and spectroscopy of single proteins using quantum logic.

Nuclear magnetic resonance spectroscopy is a powerful tool for the structural analysis of organic compounds and biomolecules but typically requires macroscopic sample quantities. We use a sensor, which consists of two quantum bits corresponding to an electronic spin and an ancillary nuclear spin, to demonstrate room temperature magnetic resonance detection and spectroscopy of multiple nuclear species within individual ubiquitin proteins attached to the diamond surface. Using quantum logic to improve readout fidelity and a surface-treatment technique to extend the spin coherence time of shallow nitrogen-vacancy centers, we demonstrate magnetic field sensitivity sufficient to detect individual proton spins within 1 second of integration. This gain in sensitivity enables high-confidence detection of individual proteins and allows us to observe spectral features that reveal information about their chemical composition.

SSX2-4 expression in early-stage non-small cell lung cancer.

The expression of cancer/testis antigens SSX2, SSX3, and SSX4 in non-small cell lung cancers (NSCLC) was examined, since they are considered promising targets for cancer immunotherapy due to their immunogenicity and testis-restricted normal tissue expression. We characterized three SSX antibodies and performed immunohistochemical staining of 25 different normal tissues and 143 NSCLCs. The antibodies differed in binding to two distinctive splice variants of SSX2 that exhibited different subcellular staining patterns, suggesting that the two splice variants display different functions. SSX2-4 expression was only detected in 5 of 143 early-stage NSCLCs, which is rare compared to other cancer/testis antigens (e.g. MAGE-A and GAGE). However, further studies are needed to determine whether SSX can be used as a prognostic or predictive biomarker in NSCLC.

Subnanometre resolution in three-dimensional magnetic resonance imaging of individual dark spins.

Magnetic resonance imaging (MRI) has revolutionized biomedical science by providing non-invasive, three-dimensional biological imaging. However, spatial resolution in conventional MRI systems is limited to tens of micrometres, which is insufficient for imaging on molecular scales. Here, we demonstrate an MRI technique that provides subnanometre spatial resolution in three dimensions, with single electron-spin sensitivity. Our imaging method works under ambient conditions and can measure ubiquitous 'dark' spins, which constitute nearly all spin targets of interest. In this technique, the magnetic quantum-projection noise of dark spins is measured using a single nitrogen-vacancy (NV) magnetometer located near the surface of a diamond chip. The distribution of spins surrounding the NV magnetometer is imaged with a scanning magnetic-field gradient. To evaluate the performance of the NV-MRI technique, we image the three-dimensional landscape of electronic spins at the diamond surface and achieve an unprecedented combination of resolution (0.8 nm laterally and 1.5 nm vertically) and single-spin sensitivity. Our measurements uncover electronic spins on the diamond surface that can potentially be used as resources for improved magnetic imaging. This NV-MRI technique is immediately applicable to diverse systems including imaging spin chains, readout of spin-based quantum bits, and determining the location of spin labels in biological systems.

Metabolic activity in early tendon repair can be enhanced by intermittent pneumatic compression.

Since Achilles tendon healing is protracted, more knowledge of metabolites known to meet the demands for biosynthesis and proliferation is needed. We hypothesized that essential metabolites, glutamate, glucose, lactate, pyruvate and glycerol, are present and upregulated in healing Achilles tendons. We moreover hypothesized that adjuvant intermittent pneumatic compression (IPC), which increases blood flow, upregulates metabolite concentrations. Twenty patients with acute Achilles tendon rupture were recruited, operated, and included. The control group, 15 patients, received plaster cast immobilization, while five patients received adjuvant foot IPC beneath the plaster cast. At 2 weeks postoperatively, microdialysis of the healing and contralateral intact Achilles tendons was followed by quantification of metabolites. Healing compared to intact tendons of the controls exhibited significantly increased concentrations (mM) of glutamate (60 ± 14 vs 20 ± 11), lactate (1.15 ± 0.60 vs 0.64 ± 0.35), and pyruvate (81 ± 29 vs 35 ± 25, µM). Healing tendons of the IPC vs control group displayed higher levels of glutamate (84 ± 15 vs 62 ± 16) and glucose (3.44 ± 0.62 vs 2.62 ± 0.72); (P < 0.05) and trends toward higher concentrations of pyruvate, lactate, and glycerol (P < 0.10). The present study demonstrates that early Achilles tendon repair entails and upregulates local essential metabolites. This metabolic response can, during tendon healing with plaster cast immobilization, be promoted by adjuvant IPC.

Nanomechanical measurement of magnetostriction and magnetic anisotropy in (Ga,Mn)As.

A GaMnAs nanoelectromechanical resonator is used to obtain the first measurement of magnetostriction in a dilute magnetic semiconductor. Resonance frequency shifts induced by field-dependent magnetoelastic stress are used to simultaneously map the magnetostriction and magnetic anisotropy constants over a wide range of temperatures. Owing to the central role of carriers in controlling ferromagnetic interactions in this material, the results appear to provide insight into a unique form of magnetoelastic behavior mediated by holes.

Interrater reliability of three clock drawing test scoring systems.

This study demonstrates the reliability of 3 Clock Drawing Test (CDT) scoring systems when applied to the protocols of stroke patients. The sample included 20 randomly selected sets of both freehand and predrawn circle versions ofthe CDT completed by patients undergoing comprehensive stroke rehabilitation. The protocols were scored independently by 2 raters using each of 3 published scoring systems (Freedman et al., 1994; Libon, Malamut, Swenson, Sands, & Cloud, 1996; Rouleau, Salmon, Butters, Kennedy, & McGuire, 1992). Interrater agreement and intrarater consistency were measured using the intraclass correlation coefficient (ICC). The results demonstrate that the raters used comparable criteria for each score (high interrater reliability) and that each applied similar scoring criteria throughout the set of protocols (high intrarater consistency). Scores related to the overall contour of the clockface tended to have lower ICCs. Reliability coefficients were comparable for both CDT versions. The results provide evidence for the accurate and consistent scoring of the CDT in stroke.

A double-blind placebo-controlled crossover study of phenytoin in individuals with impulsive aggression.

The present study examines the behavioral and psychophysiological effects of phenytoin (PHT) in individuals who display impulsive-aggressive outbursts. In a double-blind placebo-controlled crossover design, individuals meeting previously established criteria for impulsive aggression were administered PHT and placebo during separate 6-week conditions. The efficacy measures used were the Overt Aggression Scale (OAS) and the Profile of Mood States (POMS). Psychophysiological measures (evoked potentials) were taken at baseline and at the end of each 6-week condition. Photic stimulation was used to evoke the mid-latency P1-N1-P2 waveform complex. Analysis indicated a significant decrease in the frequency of impulsive-aggressive outbursts during PHT administration compared to baseline and placebo. Analysis of the psychophysiological data showed significantly increased P1 amplitude and significantly longer N1 latency during PHT administration. In addition, a reduction in N1 amplitude during PHT administration was also suggested. These findings indicate reparation of physiological abnormalities previously observed in impulsive-aggressive individuals and imply more efficient sensory processing and effective orienting of attention. Taken together, these results provide insight as to the physiological mechanisms by which PHT serves to ameliorate impulsive-aggressive behavior.

The WCST-64: a standardized short-form of the Wisconsin Card Sorting Test.

The Wisconsin Cart Sorting Test (WCST) is a well-established measure of executive function. Practical and financial constraints have increased the need for abbreviated neuropsychological procedures. A number of abbreviated versions of the WCST have been introduced and cogent arguments can be made for one over another in certain situations. However, the single deck, 64-card WCST (WCST-64) is the most logical and practical short form. Psychological Assessment Resources (PAR) has recently published a new manual with comprehensive norms for the WCST-64. This paper reviews the new product, discusses the comparability of the WCST-64 and the standard version, and suggests directions for future research.

NF2 status of meningiomas is associated with tumour localization and histology.

In approximately 60% of sporadic meningiomas, the tumour suppressor gene NF2, located on chromosome 22q, is inactivated. Mutations in the NF2 gene have been specifically reported in transitional and fibrous, but not meningothelial, meningiomas. Since meningothelial meningiomas frequently occur in anterior parts of the skull base, the association between tumour localization, size, histological subtype and NF2 status was investigated in a group of 42 sporadic meningiomas. NF2 status was determined by LOH analysis, karyotyping and FISH. Tumour size and site were evaluated by CT scans and MRIs. A strong correlation between tumour localization in the anterior skull base and intact 22q was revealed (p=0.003). On the other hand, tumour localization at the convexity was associated with disruption of NF2 (p=0.023). Furthermore, an association between chromosome 22 status and histological subtype was observed: abnormalities of chromosome 22q were more frequent in transitional and fibrous meningiomas than in the meningothelial variant (p<0.001). Also, the meningothelial meningiomas were more often located in the anterior skull base (p<0.006). Based on these findings, it is concluded that an alternative histogenesis and genetic pathway is likely to exist for meningiomas arising in the anterior skull base.

Personality and neurocognitive correlates of impulsive aggression in long-term survivors of severe traumatic brain injury.

This study addresses a common outcome of severe traumatic brain injury (TBI), disinhibited aggressive behaviour. This behaviour has been classified in aggression literature as 'impulsive aggression' (IA). The purpose was to: (1) characterize those TBI patients who are likely to be an aggression risk, and (2) determine if TBI patients with IA demonstrate personality style and neurocognitive performance similar to that seen in other IA groups. Participants were 45 survivors of severe TBI (26 of whom had persisting problems with IA), who were clients of a residential brain injury treatment facility. IA participants had a higher incidence of pre-morbid aggressive behaviour, were younger, had a shorter tenure in the programine, and were more impulsive, irritable, and antisocial than the non-aggressive control participants. Unlike past research, no neurocognitive differences were found. The results are discussed in terms of the conceptualization, identification, and treatment of persisting IA in severe TBI.

Identification of malingered head injury on the wechsler adult intelligence scale - 3rd edition.

Head injured patients show an IQ subtest pattern that can be discriminated from the profile produced by individuals who attempt to malinger intellectual decline due to head trauma. The current paper demonstrates that previously replicated methods for making this discrimination on the WAIS - R generalize to the WAIS - 3. The discriminant function equation accurately classified 83% of nonlitigating head-trauma patients with documented injuries and 72% of persons simulating intellectual impairment due to head trauma. A total of 45% of litigating mild head-trauma patients with purported intellectual decline but no documented loss of consciousness, hospitalization, or CT abnormality were classified as malingering by the discriminant function. A Vocabulary-Digit Span difference score provided 71% overall diagnostic accuracy, and may be informative when screening profiles by visual inspection or when complete WAIS - 3 results are unavailable.

Classification accuracy of the portland digit recognition test in traumatic brain injury.

This study examined the classification accuracy of the Portland Digit Recognition Test (PDRT) in traumatic brain injury (TBI). It differs from past studies in assigning patients to malingering and control groups on the basis of compensation-seeking status and the presence of external markers for malingering. Sensitivity and Specificity were.77 and 1.00, respectively. Past research comparing compensation-seekers to noncompensation-seekers reported Sensitivities of.33 or lower (Specificity is always high). This study demonstrates that past research has seriously underestimated the Sensitivity of the PDRT and raises questions about the true Sensitivity of other malingering techniques as well.

Symptom validity testing: a critical review.

This paper provides a comprehensive review of the published literature on symptom validity tests (SVT) and, with the accompanying tables, serves as a reference to assist in their selection, interpretation, and defense. Because malingering is inherently an applied problem that frequently arises in a medico-legal context, the use of SVTs must meet certain standards. Thus, a number of methodological and theoretical weaknesses of SVT research which limit the use of SVTs as clinical tools and sources of evidence are highlighted. These criticisms incorporate recommendations which must be addressed if conclusions based on SVT data are to meet the increasingly rigorous standards for the admissibility of scientific evidence.

Paced Visual Serial Addition Test: an alternative measure of information processing speed.

The Paced Auditory Serial Addition Test (PASAT; Gronwall, 1977; Gronwall & Sampson, 1974) is a measure of attention and information processing speed sensitive to mild traumatic brain injury (MTBI), but it is aversive and inappropriate for many other neurologically impaired patients. This study examines a simpler, less aversive visual analog of the PASAT (the Paced Visual Serial Addition Test; PVSAT) in a sample of 74 college students (26 with a history of TBI). Results indicated that the PVSAT is moderately correlated with and less difficult than the PASAT. Both tests had identical relations to other measures of attention. Neither the PVSAT, PASAT, nor the other attentional measures differentiated participants with MTBI from normal controls in a college population. This preliminary study thus demonstrates the comparability of the two tests and presents the PVSAT as a viable alternative to the PASAT. Directions for future research and applications of these findings are discussed.

Developmental changes in California Card Sorting Test performance.

The purpose of the present study was to determine 1) if performance on the California Card Sorting Test (CCST) follows the same developmental gradient as other measures of concept formation and 2) whether the components of concept formation tapped by the CCST are developmentally dissociable. Participants were 68 children and young adults in four age-based groups: 7 to 9 years (n = 13); 10 to 12 years (n = 16); 17 to 19 (n = 20); and, 20 to 22 years (n = 19). All were of average or higher measured intelligence and screened for neurological, psychiatric, reading and attentional disorder. The findings of the present study suggest that like many other concept formation tasks, CCST performance approximates adult levels by age 10. Further, the different components of concept formation measured by the CCST are dissociable in the youngest children with the development of concept recognition preceding sorting ability.

Construct validity and predictive value of the Hooper Visual Organization Test in stroke rehabilitation.

The Hooper Visual Organization Test (HVOT; Hooper, 1958) is a commonly used measure of visual perceptual function. However, serious questions have recently been raised about its construct validity (i.e., the role of object naming). This study further examined the HVOT's construct validity and began exploring its contribution to outcome prediction in stroke rehabilitation. Participants were 101 rehabilitation inpatients suffering from recent cerebrovascular accidents. Each participant was administered the HVOT as part of a comprehensive neuropsychological evaluation. Wechsler Adult Intelligence Scale-Revised (Wechsler, 1981) Object Assembly, Picture Completion, and Cognistat Naming were significantly and uniquely correlated with the HVOT and accounted for about 45% of its variance. The HVOT's value in outcome prediction was examined by correlating HVOT with admission and discharge Functional Independence Measure (FIM; Granger & Hamilton, 1990; Hamilton, Granger, Sherwin, Zielezny, & Tashman, 1987) scores. While correlating weakly with some FIM domains, when admission FIM was controlled, the relation between HVOT and discharge FIM became nonsignificant. Implications of these data for the HVOT's clinical utility are discussed.

Temporal stability of the Wisconsin Card Sorting Test in an untreated patient sample.

This study evaluates the temporal stability of the Wisconsin Card Sorting Test (WCST). The only previous similar study found unacceptably low test-retest stability in a non-patient elderly sample. In contrast, the present study utilizes 29 untreated obstructive sleep apnea patients who are more typical of persons likely to receive the WCST clinically. The 11 WCST scores examined demonstrated test-retest correlations from .34 to .83 (mean = .64). Six of 11 correlations were within .10 of the .80 criterion for clinical utility and there was minimal change across sessions. The current findings justify greater optimism regarding the test-retest reliability of the WCST.