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Ultrathin films and multilayers, with controlled thickness down to single atomic layers, are critical for advanced technologies ranging from nanoelectronics to spintronics to quantum devices. However, for thicknesses less than 10 nm, surfaces and dopants contribute significantly to the film properties, which can differ dramatically from that of bulk materials. For amorphous films being developed as low dielectric constant interfaces for nanoelectronics, the presence of surfaces or dopants can soften films and degrade their mechanical performance. Here we use coherent short-wavelength light to fully and nondestructively characterize the mechanical properties of individual films as thin as 5 nm within a bilayer. In general, we find that the mechanical properties depend both on the amount of doping and the presence of surfaces. In very thin (5-nm) silicon carbide bilayers with low hydrogen doping, surface effects induce a substantial softening - by almost an order of magnitude - compared with the same doping in thicker (46-nm) bilayers. These findings are important for informed design of ultrathin films for a host of nano- and quantum technologies, and for improving the switching speed and efficiency of next-generation electronics.

Stress and anxiety are significant problems for individuals living with HIV. Mind-body therapies such as progressive muscle relaxation training and guided imagery (PMRT-GI) are effective in treating stress and anxiety in chronically ill persons. The purpose of this study was to identify key elements of an effective and culturally acceptable PMRT-GI intervention for economically disadvantaged persons with HIV. PMRT-GI was provided to 24 participants from African American, White, and Hispanic backgrounds. Using Colaizzi's phenomenological method, participants were interviewed about their experiences with PMRT-GI. Responses were tape-recorded, read, and reread; significant phrases and sentences were identified; meanings were formulated; and results were validated with participants. Five themes emerged: another world, feeling content, ease in muscle tension, one-on-one, and soft music. Background information and past experience with complementary and alternative methods were obtained. [ABSTRACT FROM AUTHOR]

There is little data on female-to-female transmission of HIV. Some women who have sex with women (WSW) have other high-risk behaviors that could lead to HIV infection. The belief that WSW are at no risk may lead to unsafe sexual practices. In this study, a convenience sample of 78 women was surveyed in order to explore the perception of HIV risk among lesbians, their sexual behaviors, and their sources of information about safer sex. Fifty-three percent reported they were at low risk for contracting HIV. Women reported knowledge of barrier methods (89% to 99%) and no sex during menstruation (92%). However, 35% to 40% reported no knowledge of less common safer sex practices. Women reported their source of knowledge as media (36%), workshops (22%), and friends (12%). Eighty-five percent stated that their health care provider knew they were lesbian, but only 15% reported receiving safer sex education. Nurses and nurse practitioners are aptly poised to provide critical HIV education and health care for this population. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine how violence co-occurs with drug use and HIV/AIDS high-risk behaviors among women incarcerated for drug use. This study was a supplement to a larger, experimental study designed to reduce HIV/AIDS high-risk behaviors among incarcerated female drug users. The women who participated (N = 170) reported that violence was a major part of their lives and affected many of their behaviors. Among these 170 women, 26.6% used condoms for oral sex, 46.4% for vaginal intercourse, and 65% were either sexually or physically abused. Intimate partner abuse was reported by 33.9% of the women. About 16% reported forced sexual activity; and 17.5% feared their partners. Women who refused to give oral sex to their male partners and those who insisted on condom use during oral sex prior to jail were more likely to be sexually or physically abused (chi square = 4.104; chi square = 3.886, p < .05, respectively). Although statistically significant interrelationships were not found among the three variables, signficant bivariate relationships were found between intimate violence and HIV/AIDS high-risk behaviors. [ABSTRACT FROM AUTHOR]

Posttraumatic stress disorder (PTSD) is associated with an increased risk of developing cardiovascular disease, especially in women. Evidence indicates that men with PTSD exhibit lower maximal oxygen uptake (V̇o 2max ) relative to controls; however, whether V̇o 2max is blunted in women with PTSD remains unknown. Furthermore, it is unclear what determinants (i.e., central and/or peripheral) of V̇o 2max are impacted by PTSD. Therefore, we evaluated the central (i.e., cardiac output; Q̇ c ) and peripheral (i.e., arteriovenous oxygen difference) determinants of V̇o 2max in women with PTSD; hypothesizing that V̇o 2max would be lower in women with PTSD compared with women without PTSD (controls), primarily due to smaller increases in stroke volume (SV), and therefore Q̇ c . Oxygen uptake (V̇o 2 ), heart rate (HR), Q̇ c , SV, and arteriovenous oxygen difference were measured in women with PTSD ( n = 14; mean [SD]: 43 [11] yr,) and controls ( n = 17; 45 [11] yr) at rest, and during an incremental maximal treadmill exercise test, and the Q̇ c /V̇o 2 slope was calculated. V̇o 2max was not different between women with and without PTSD (24.3 [5.6] vs. 26.4 [5.0] mL/kg/min; P = 0.265). However, women with PTSD had higher Q̇ c [ P = 0.002; primarily due to greater SV ( P = 0.069), not HR ( P = 0.285)], and lower arteriovenous oxygen difference ( P = 0.002) throughout exercise compared with controls. Furthermore, the Q̇ c /V̇o 2 slope was steeper in women with PTSD relative to controls (6.6 [1.4] vs. 5.7 [1.0] AU; P = 0.033). Following maximal exercise, women with PTSD exhibited slower HR recovery than controls ( P = 0.046). Thus, despite attenuated peripheral oxygen extraction, V̇o 2max is not reduced in women with PTSD, likely due to larger increases in Q̇ c . NEW & NOTEWORTHY The current study indicates that V̇o 2max is not different between women with and without PTSD; however, women with PTSD exhibit blunted peripheral extraction of oxygen, thus requiring an increase in Q̇ c to meet metabolic demand during exercise. Furthermore, following exercise, women with PTSD demonstrate impaired autonomic cardiovascular control relative to sedentary controls. We interpret these data to indicate that women with PTSD demonstrate aberrant cardiovascular responses during and immediately following fatiguing exercise.

Introduction: Women veterans using Veterans Health Care Administration maternity benefits have a high prevalence of mental health disorders, including depression, PTSD, and anxiety. Additionally, women with psychiatric histories often experience a relapse or worsening of symptoms during pregnancy and postpartum. Adequate perinatal mental healthcare engagement is critical to optimizing outcomes for mother and child., Materials and Methods: This study evaluated psychiatric symptom severity and predictors of women veteran's mental health treatment engagement during pregnancy and postpartum at the VA North Texas Health Care System. Seventy women using Veterans Health Administration were assessed longitudinally via chart review and interviews (including the Edinburgh Postnatal Depression Scale) during pregnancy and postpartum. A Friedman test was used to evaluate the change in symptom severity during (1) the 6 months before pregnancy, (2) pregnancy, and (3) postpartum. Multivariate logistic regressions were used to determine predictors of attending outpatient mental health appointments. Potential predictors examined included sociodemographic factors, symptoms of depression, history of military sexual assault, presence of a pre-pregnancy psychiatric diagnosis, and attendance of mental health appointments before pregnancy., Results: Approximately 40% of participants demonstrated at least mild psychiatric symptoms before pregnancy, and symptom severity did not significantly change across the perinatal period (pre-pregnancy, pregnancy, and postpartum) X2 (2, n = 70) = 3.56, P = .17. Depressive symptoms during the 2nd or 3rd trimester were a significant predictor for attendance of mental health appointments during both pregnancy (OR = 1.18, 95% CI, 1.04 to 1.34) and postpartum (OR = 1.18, 95% CI, 1.02 to 1.36). An active psychiatric diagnosis during the 6 months before pregnancy was also a significant predictor of attendance following delivery (OR = 14.63, 95% CI, 1.55 to 138.51)., Conclusion: Our results demonstrate that women with prior histories of mental health conditions will continue to be symptomatic, and this is a good predictor of mental health treatment engagement during the perinatal period., (Published by Oxford University Press on behalf of the Association of Military Surgeons of the United States 2021. This work is written by (a) US Government employee(s) and is in the public domain in the US.)

Muscle sympathetic nerve activity (MSNA) increases during isometric exercise via increased firing of low-threshold action potentials (AP), recruitment of larger, higher-threshold APs, and synaptic delay modifications. Recent work found that women with post-traumatic stress disorder (PTSD) demonstrate exaggerated early-onset MSNA responses to exercise; however, it is unclear how PTSD affects AP recruitment patterns during fatiguing exercise. We hypothesized that women with PTSD (n = 11, 43 [11] [SD] years) would exhibit exaggerated sympathetic neural recruitment compared to women without PTSD (controls; n = 13, 40 [8] years). MSNA and AP discharge patterns (via microneurography and a continuous wavelet transform) were measured during 1 min of baseline, isometric handgrip exercise (IHG) to fatigue, 2 min of post-exercise circulatory occlusion (PECO), and 3 min of recovery. Women with PTSD were unable to increase AP content per burst compared to controls throughout IHG and PECO (main effect of group: P = 0.026). Furthermore, relative to controls, women with PTSD recruited fewer AP clusters per burst during the first (controls: ∆1.3 [1.2] vs. PTSD: ∆-0.2 [0.8]; P = 0.016) and second minute (controls: ∆1.2 [1.1] vs. PTSD: ∆-0.1 [0.8]; P = 0.022) of PECO, and fewer subpopulations of larger, previously silent axons during the first (controls: ∆5 [4] vs. PTSD: ∆1 [2]; P = 0.020) and second minute (controls: ∆4 [2] vs. PTSD: ∆1 [2]; P = 0.021) of PECO. Conversely, PTSD did not modify the AP cluster size-latency relationship during baseline, the end of IHG, or PECO (all P = 0.658-0.745). Collectively, these data indicate that women with PTSD demonstrate inherent impairments in the fundamental neural coding patterns elicited by the sympathetic nervous system during IHG and exercise pressor reflex activation., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany.)

Background: Women Veterans using Veterans Affairs (VA) maternity care represent a high-risk population owing to the high prevalence of psychiatric disorders, such as depression, anxiety, and posttraumatic stress disorder (PTSD). Given the increased risk of symptom recurrence and/or medication discontinuation during pregnancy, the aim of this study was to understand the relationship between mental health and health care utilization in pregnant Veterans within the Veterans Health Administration (VHA). Materials and Methods: Women with a confirmed pregnancy were recruited from 15 VA sites across the United States. Data sources included diagnosis codes, clinic stop codes for outpatient visits, and 30-day antidepressant prescriptions in the electronic health record. Results: Overall, mental health visits increased slightly from prepregnancy to pregnancy before decreasing in the postpartum period. For women with a prepregnancy diagnosis of depression, anxiety, and/or PTSD, there was an increase in psychotherapy utilization during the pregnancy and postpartum periods, whereas the percentage of women utilizing antidepressants only or antidepressants plus therapy decreased during these same time periods. A small proportion of women with histories of mental health conditions did not utilize mental health care within the VA during pregnancy and postpartum. Conclusions: These results inform our understanding of VA health care utilization patterns in pregnant Veterans, particularly those with a history of depression, PTSD, and/or anxiety. The strong utilization of VA mental health services during this time emphasizes the importance of optimizing the coordination of care between VA mental health providers and community-provided obstetric care to enhance outcomes for both mother and child.

Posttraumatic stress disorder (PTSD) is more prevalent in women and associated with greater risk of major forms of cardiovascular disease, but physiological mechanisms underlying this association remain unknown. We hypothesized that abnormal sympathetic responses to sympathoexcitatory stimuli might predispose PTSD patients to a greater risk of cardiovascular disease. We examined changes in integrated muscle sympathetic nerve activity (MSNA) burst and multiunit action potential (AP) recruitment patterns as well as hemodynamic responses during cold pressor test (CPT) in 14 women with PTSD and 14 healthy control subjects. Data were collected during 1-min baseline, 2-min CPT, and 3-min recovery. At baseline, blood pressure (BP) was not different between groups; however, heart rate and sympathetic neural activity were greater in women with PTSD [MSNA burst frequency (BF): 27 ± 13 vs. 18 ± 14 bursts/min ( P = 0.04); AP frequency: 272 ± 152 vs. 174 ± 146 spikes/min ( P = 0.03)]. In response to CPT, BP responses exhibited a significant group × time interaction ( P = 0.01) highlighted by a significant diastolic BP main group effect ( P = 0.048) despite the finding that increases in integrated MSNA burst responses were not different between groups ( P > 0.05). However, compared with control subjects, AP firing frequency (group × time interaction P = 0.0001, group P = 0.02) and AP per burst (group × time interaction P = 0.03, group P = 0.03) were augmented in women with PTSD. Collectively, women with PTSD exhibited a greater pressor response and an exaggerated sympathetic neural recruitment pattern during sympathoexcitatory stimuli that may, in part, explain the propensity toward developing hypertension and cardiovascular disease later in life. NEW & NOTEWORTHY The novel findings of the present study are that women with posttraumatic stress disorder (PTSD) have an augmented pressor response to the sympathoexcitatory stimulus of a cold pressor test (CPT) compared with healthy control subjects. Although integrated muscle sympathetic nerve activity burst responses were not significantly different between groups, total sympathetic action potential discharge in response to the CPT was markedly elevated in women with PTSD exhibiting increased firing of low-threshold axons as well as the recruitment of latent subpopulations of larger-sized axons that are otherwise silent at baseline. Aberrant autonomic circulatory control in response to sympathoexcitatory stimulus may in part explain the propensity toward developing hypertension and cardiovascular disease in this population.

Posttraumatic stress disorder (PTSD) is a psychiatric illness that is more prevalent in women, and accumulating evidence suggests a link between PTSD and future development of cardiovascular disease. The underlying mechanisms are unclear, but augmented sympathetic reactivity to daily stressors may be involved. We measured muscle sympathetic nerve activity (MSNA), blood pressure (BP), and heart rate responses in 14 women with PTSD and 14 healthy women (controls) during static handgrip (SHG) exercise to fatigue at 40% of maximal voluntary contraction (MVC). Two minutes of postexercise circulatory arrest (PECA) was followed immediately after SHG to fatigue. MVC and the time to fatigue during SHG did not differ between groups (both P > 0.05). At the first 30 s of SHG, women with PTSD showed augmented sympathetic neural [mean ± SD, ∆MSNA burst frequency (BF): 5 ± 4 vs. 2 ± 3 bursts/30 s, P = 0.02 and ∆MSNA total activity (TA): 82 ± 58 vs. 25 ± 38 arbitrary units/30 s, P = 0.004] and pressor (∆systolic BP: 10 ± 5 vs. 4 ± 3 mmHg, P = 0.003) responses compared with controls. However, MSNA and BP responses at fatigue and during PECA were not different between groups. More interestingly, the augmented initial neural and pressor responses to SHG were associated with greater awake systolic BP variability during ambulation in women with PTSD (MSNA BF: r  = 0.55, MSNA TA: r  = 0.62, and SBP: r  = 0.69, all P < 0.05). These results suggest that early onset exercise pressor response in women with PTSD may be attributed to enhanced mechano- rather than metaboreflexes, which might contribute to the mechanisms underlying the link between PTSD and cardiovascular risk. NEW & NOTEWORTHY The novel findings of the current study are that women with posttraumatic stress disorder (PTSD) exhibited augmented sympathetic neural and pressor responses at the first 30 s of submaximal isometric muscle contraction. More interestingly, exaggerated neurocirculatory responses at the onset of muscle contraction were associated with greater ambulatory awake systolic blood pressure fluctuations in women with PTSD. Our findings expand the knowledge on the physiological mechanisms that perhaps contribute to increased risk of cardiovascular disease in such a population.

Women are two to three times more likely to develop posttraumatic stress disorder (PTSD) compared with men after exposure to a major trauma, and PTSD is associated with increased risk for cardiovascular disease in later life. The underlying mechanisms are unclear, but alterations in cardiac function may be involved. We hypothesized that women with PTSD have reduced left ventricular (LV) diastolic function. We studied 14 women with PTSD (PTSD group) and 14 women without PTSD (controls) using echocardiography Doppler to evaluate LV diastolic function, including peak velocities (E and A waves) in transmitral flow; diastolic, atrial kick, and systolic waveform velocities (e', a', and s') in tissue Doppler; the ratio between early mitral inflow velocity and mitral annular early diastolic velocity (E/e'); and velocity of propagation ( V p ) . Baseline characteristics including age, body size, blood pressure, and heart rate were not significantly different between the two groups. Compared with the control group, women with PTSD showed greater E/e' (controls vs. PTSD group: 7.0 ± 1.3 vs. 9.1 ± 1.3, P = 0.002) and smaller V p (controls vs. PTSD group: 63.7 ± 11.3 vs. 47.5 ± 6.9 cm/s, P = 0.003). These results suggest that women with PTSD have reduced LV diastolic function, which may contribute, at least in part, to the increased risk of cardiovascular disease later in life.

Posttraumatic stress disorder (PTSD) is associated with structural and functional alterations in a number of interacting brain regions, but the physiological mechanism for the high risk of cerebrovascular disease or impairment in brain function remains unknown. Women are more likely to develop PTSD after a trauma than men. We hypothesized that cerebral blood flow (CBF) regulation is impaired in women with PTSD, and it is associated with impairment in cognitive function. To test our hypothesis, we examined dynamic cerebral autoregulation (CA) and cognitive function by using a transfer function analysis between arterial pressure and middle cerebral artery blood velocity and the Stroop Color and Word test (SCWT), respectively. We did not observe any different responses in these hemodynamic variables between women with PTSD ( n = 15) and healthy counterparts (all women; n = 8). Cognitive function was impaired in women with PTSD; specifically, reaction time for the neutral task of SCWT was longer in women with PTSD compared with healthy counterparts ( P = 0.011), but this cognitive dysfunction was not affected by orthostatic stress. On the other hand, transfer function phase, gain, and coherence were not different between groups in either the supine or head-up tilt (60°) position, or even during the cognitive challenge, indicating that dynamic CA was well maintained in women with PTSD. In addition, there was no relationship between cognitive function and dynamic CA. These findings suggest that PTSD-related cognitive dysfunction may not be due to compromised CBF regulation. NEW & NOTEWORTHY Cognitive function was impaired; however, dynamic cerebral autoregulation (CA) as an index of cerebral blood flow regulation was not impaired during supine and 60° head-up tilt in women with PTSD compared with healthy females. In addition, there was no relationship between cognitive function and dynamic CA. These findings suggest that the mechanism of PTSD-related cognitive dysfunction may not be due to CBF regulation.

Extrusion-based fused deposition modeling (FDM) introduces inter-bead pores into dense materials, which results in part-to-part mechanical property variations, i.e., low mechanical reliability. In addition, the internal structure of FDMed materials can be made porous intentionally to tailor mechanical properties, introduce functionality, reduce material consumption, or decrease production time. Despite these potential benefits, the effects of porosity on the mechanical reliability of FDMed composites are still unclear. Accordingly, we investigated the stochastic fracture of 241 FDMed short-carbon-fiber-reinforced-ABS with porosity ranging from 13 to 53 vol.% under tensile load. Weibull analysis was performed to quantify the variations in mechanical properties. We observed an increase in Weibull modulus of fracture/tensile strength for porosity higher than ~40 vol.% and a decrease in Weibull modulus of fracture strain for an increase in porosity from 25 to 53 vol.%. Micromechanics-based 2D simulations indicated that the mechanical reliability of FDMed composites depends on variations in bead strength and elastic modulus of beads. The change in raster orientation from 45°/-45° to 0° more than doubled the Weibull modulus. We identified five different types of pores via high-resolution X-ray computed tomography. A 22% and 48% decrease in carbon fiber length due to extrusion was revealed for two different regions of the filament.

Introduction: The safety, feasibility, and efficacy of a 12-week structured exercise program targeting post-traumatic stress disorder (PTSD) in women Veterans of childbearing age was tested in a pilot study., Materials and Methods: Thirty-one women Veterans of childbearing age were enrolled in the study, 22 remained eligible after the baseline assessment, and 16 completed the exercise protocol. The exercise program consisted of moderate intensity aerobic exercise (brisk walking), 4 times a week, for 12 weeks. Data were collected on duration, intensity, and side effects. The Clinician Administered PTSD Scale was administered at baseline and at the end of 12 weeks. Weekly assessments provided data on PTSD and depression symptoms, pain, and quality of life., Results: Both post-traumatic and depressive symptoms improved significantly by the end of study. There were no adverse events related to exercise. A small focus group provided subjective experiences supporting positive effects of exercise on emotion and physical health., Conclusion: The preliminary results of this study suggests that 12 weeks of moderate intensity aerobic exercise may be a promising intervention for PTSD in women Veterans of childbearing potential. Further controlled studies are warranted to determine efficacy of moderate intensity exercise as a treatment modality for this population., (Reprint & Copyright © 2017 Association of Military Surgeons of the U.S.)

Precise characterization of the mechanical properties of ultrathin films is of paramount importance for both a fundamental understanding of nanoscale materials and for continued scaling and improvement of nanotechnology. In this work, we use coherent extreme ultraviolet beams to characterize the full elastic tensor of isotropic ultrathin films down to 11 nm in thickness. We simultaneously extract the Young's modulus and Poisson's ratio of low-k a-SiC:H films with varying degrees of hardness and average network connectivity in a single measurement. Contrary to past assumptions, we find that the Poisson's ratio of such films is not constant but rather can significantly increase from 0.25 to >0.4 for a network connectivity below a critical value of ∼2.5. Physically, the strong hydrogenation required to decrease the dielectric constant k results in bond breaking, lowering the network connectivity, and Young's modulus of the material but also decreases the compressibility of the film. This new understanding of ultrathin films demonstrates that coherent EUV beams present a new nanometrology capability that can probe a wide range of novel complex materials not accessible using traditional approaches.

Analytical probes capable of mapping molecular composition at the nanoscale are of critical importance to materials research, biology and medicine. Mass spectral imaging makes it possible to visualize the spatial organization of multiple molecular components at a sample's surface. However, it is challenging for mass spectral imaging to map molecular composition in three dimensions (3D) with submicron resolution. Here we describe a mass spectral imaging method that exploits the high 3D localization of absorbed extreme ultraviolet laser light and its fundamentally distinct interaction with matter to determine molecular composition from a volume as small as 50 zl in a single laser shot. Molecular imaging with a lateral resolution of 75 nm and a depth resolution of 20 nm is demonstrated. These results open opportunities to visualize chemical composition and chemical changes in 3D at the nanoscale.

Understanding thermal transport from nanoscale heat sources is important for a fundamental description of energy flow in materials, as well as for many technological applications including thermal management in nanoelectronics and optoelectronics, thermoelectric devices, nanoenhanced photovoltaics, and nanoparticle-mediated thermal therapies. Thermal transport at the nanoscale is fundamentally different from that at the macroscale and is determined by the distribution of carrier mean free paths and energy dispersion in a material, the length scales of the heat sources, and the distance over which heat is transported. Past work has shown that Fourier's law for heat conduction dramatically overpredicts the rate of heat dissipation from heat sources with dimensions smaller than the mean free path of the dominant heat-carrying phonons. In this work, we uncover a new regime of nanoscale thermal transport that dominates when the separation between nanoscale heat sources is small compared with the dominant phonon mean free paths. Surprisingly, the interaction of phonons originating from neighboring heat sources enables more efficient diffusive-like heat dissipation, even from nanoscale heat sources much smaller than the dominant phonon mean free paths. This finding suggests that thermal management in nanoscale systems including integrated circuits might not be as challenging as previously projected. Finally, we demonstrate a unique capability to extract differential conductivity as a function of phonon mean free path in materials, allowing the first (to our knowledge) experimental validation of predictions from the recently developed first-principles calculations.

The recent surge in Operation Enduring Freedom/Operation Iraqi Freedom/Operation New Dawn (OEF/OIF/OND) era women Veterans, most of whom are younger compared to other women Veterans, presenting with mental health issues is expected to pose new clinical challenges. Treatment of mental health conditions in women Veterans is not considered comprehensive without adequate examination of the impact of reproductive events across the life span, such as their menstrual cycle, pregnancy and postpartum period, and menopausal transition. The overarching aim of this article is to discuss emerging clinical issues in managing common psychiatric conditions such as posttraumatic stress disorder and major depression during pregnancy and postpartum period in the VA healthcare system and secondly, to identify steps to advance the knowledge and understanding of these complex issues. Information to be gained in this area has immediate clinical application in the overall management of major psychiatric conditions in women Veterans during pregnancy and postpartum, and implications for policy-making decisions.

A self-contained electro-optical module for scanning extreme ultraviolet (EUV) reflection microscopy at 13.5 nm wavelength has been developed. The system has been designed to work with stand-alone commercially available EUV high harmonic generation (HHG) sources through the implementation of narrowband harmonic selecting multilayers and off-axis elliptical short focal length zoneplates. The module has been successfully integrated into an EUV mask scanning microscope achieving diffraction limited imaging performance (84 nm point spread function).

We demonstrate the first real-space recording of nanoscale dynamic interactions using single-shot soft x-ray (SXR) full-field laser microscopy. A sequence of real-space flash images acquired with a table-top SXR laser was used to capture the motion of a rapidly oscillating magnetic nanoprobe. Changes of 30 nm in the oscillation amplitude were detected when the nanoprobe was made to interact with stray fields from a magnetic sample. The table-top visualization of nanoscale dynamics in real space can significantly contribute to the understanding of nanoscale processes and can accelerate the development of new nanodevices.

Diffraction efficiency of multilayer-coated blazed gratings (MBG) strongly depends on the perfection of the sawtooth-shaped layers in the overall composite structure. Growth of multilayers on sawtooth substrates should be carefully optimized to reduce groove profile distortion and, at the same time, to avoid significant roughening of multilayer interfaces. In this work, we report on a way to optimize growth of sputter-deposited Mo/Si multilayers on sawtooth substrates through variation of the sputtering gas pressure. We believe a new record for diffraction efficiency of 44% was achieved for an optimized MBG with groove density of 5250 lines/mm at the wavelength of 13.1 nm.

Ultra-high spectral resolution in the EUV and soft x-ray energy ranges requires the use of very high line density gratings with optimal design resulting in use of a Blazed Multilayer Grating (BMG) structure. Here we demonstrate the production of near-atomically perfect Si blazed substrates with an ultra-high groove density (10,000 l/mm) together with the measured and theoretical performance of an Al/Zr multilayer coating on the grating. A 1st order absolute efficiency of 13% and 24.6% was achieved at incidence angles of 11° and 36° respectively. Cross-sectional TEM shows the effect of smoothing caused by the surface mobility of deposited atoms and we correlate this effect with a reduction in peak diffraction efficiency. This work shows the high performance that can be achieved with BMGs based on small-period anisotropic etched Si substrates, but also the constraints imposed by the surface mobility of deposited species.

The type and quality of the provider-patient health care relationship impacts patient adherence. The study purpose was to convert the 5-item paper and pencil Relationships With Health Care Provider Scale (RHCPS) to a reliable and valid computer-based scale for use with older adults. Outpatient adults (N = 121) older than 59 years were recruited. The RHCPS underwent several iterations documenting internal consistency reliability, content and factorial validity, and scale usability in a computer tablet format. A total of 5 expert judges rated all 5 items as valid, which resulted in a scale content validity index of 1. Cronbach's standardized alpha was .81. Principal components analysis extracted 1 factor (eigenvalue > 1; confirmed by scree plot) as anticipated. Computer-based RHCPS has the potential to reveal valuable clinical and scientific data on patient-provider relationships among older adults.

The aim of this phenomenological study was to explore and describe patients with HIV/AIDS experiences with nausea as it affects their abilities to take medications, to eat, and to engage in life activities. Forty-five men and 21 women with a mean age of 42.33 years (SD = 8.44 years) participated in the study. Data were analyzed using Colaizzi's phenomenological method. Five themes emerged: (a) daily anticipation, (b) sensory invasion, (c) emotional medley, (d) stigma and secrecy, and (e) searching for solutions. Recommendations for staff development educators on the basis of partnerships with academia are presented.

Volume x-ray gratings consisting of a multilayer coating deposited on a blazed substrate can diffract with very high efficiency, even in high orders if diffraction conditions in-plane (grating) and out-of-plane (Bragg multilayer) are met simultaneously. This remarkable property, however, depends critically on the ability to create a structure with near atomic perfection. In this Letter we report on a method to produce these structures. We report measurements that show, for a 5000l/mm grating diffracting in the third order, a diffraction efficiency of 37.6% at a wavelength of 13.6nm. This work now shows a direct route to achieving high diffraction efficiency in high order at wavelengths throughout the soft x-ray energy range.

To extend soft x-ray microscopy to a resolution of order 10 nm or better, we developed a new nanofabrication process for Fresnel zone plate lenses. The new process, based on the double patterning technique, has enabled us to fabricate high quality gold zone plates with 12 nm outer zones. Testing of the zone plate with the full-field transmission x-ray microscope, XM-1, in Berkeley, showed that the lens clearly resolved 12 nm lines and spaces. This result represents a significant step towards 10 nm resolution and beyond.

This article reports the findings of a study investigating coping strategies used by hypersexual patients (n = 71), compared with a control group (n = 73), in their attempts to defend against shame. Coping strategies were measured using the Compass of Shame Scale (CoSS) and hypersexual behaviour was measured by the Hypersexual Behavior Inventory (HBI). A multivariate analysis of variance of between-group differences was significant, and examination of post hoc univariate tests revealed that the sample of hypersexual patients defended against shame with higher levels of withdrawal and higher tendencies to attack self and others when compared with the control group. The effect sizes of these differences were moderate to large. A categorical analysis of the patient group indicated that the greatest percentages of elevated shame scores were clustered on the Withdrawal and Attack Self subscales of the CoSS. Between-group differences on the Avoidance subscale of the CoSS were not significant. The results of this study are discussed as they pertain to clinical practice, and future recommendations for research are offered.

We report the demonstration of a reflection microscope that operates at 13.2 nm wavelength with a spatial resolution of 55+/-3 nm. The microscope uses illumination from a tabletop extreme ultraviolet laser to acquire aerial images of photolithography masks with a 20 s exposure time. The modulation transfer function of the optical system was characterized.

We have demonstrated near-wavelength resolution microscopy in the extreme ultraviolet. Images of 50 nm diameter nanotubes were obtained with a single ~1 ns duration pulse from a desktop-size 46.9 nm laser. We measured the modulation transfer function of the microscope for three different numerical aperture zone plate objectives, demonstrating that 54 nm half-period structures can be resolved. The combination of near-wavelength spatial resolution and high temporal resolution opens myriad opportunities in imaging, such as the ability to directly investigate dynamics of nanoscale structures.

Ablation of holes with diameters as small as 82 nm and very clean walls was obtained in poly(methyl methacrylate) focusing pulses from a Ne-like Ar 46.9 nm compact capillary-discharge laser with a freestanding Fresnel zone plate diffracting into third order. These results demonstrate the feasibility of using focused soft x-ray laser beams for the direct nanoscale patterning of materials and the development of new nanoprobes.

A dextran-modified poly(vinyl amine) comb-like surfactant polymer, poly(N-vinyl dextran aldonamide-co-N-vinyl hexanamide), that can surface-adsorb on hydrophobic polymeric substrates, was designed to improve the interfacial blood-compatibility of polymeric biomaterials. Medical-grade polycarbonate was selected as a model substrate because of its extensive use in blood-contacting biomedical devices like hemodialyzers, blood pumps and oxygenators. The surfactant polymer was physisorbed from aqueous solution onto the polycarbonate substrate. The surfactant coating was stable under dynamic shear conditions in whole blood, as confirmed by fluorescence microscopy and total internal reflection fluorescence (TIRF) experiments with fluorescein-labeled surfactant polymer. The coated disks and uncoated control disks were exposed to platelet-rich plasma (PRP) and whole human blood in a rotating disk system (RDS) to study platelet-adhesion under dynamic shear stress environments. Adhered platelets were stained with fluorescein isothiocyante (FITC)-tagged anti-CD41a monoclonal antibody and imaged by epifluorescence microscopy. Complimentary images were obtained by phase-contrast microscopy. Platelet adhesion on the surfactant-coated disks was reduced by approximately 90%, compared with uncoated disks. The images also showed a concomitant reduction in platelet-derived microparticles on surfactant-coated disks, compared with uncoated disks. The results suggest potential application of carbohydrate-modified surfactant polymers as a glycocalyx-mimetic non-thrombogenic interfacial coating for blood-contacting biomaterials.

We have acquired images with a spatial resolution better than 38 nm by using a tabletop microscope that combines 13 nm wavelength light from a high-brightness tabletop laser and Fresnel zone plate optics. These results open a gateway to the development of compact and widely available extreme-ultraviolet imaging tools capable of inspecting samples in a variety of environments with a 15-20 nm spatial resolution and a picosecond time resolution.

Full-field soft X-ray microscopy in combination with X-ray magnetic circular dichroism as contrast mechanism is a powerful technique to image with elemental specificity magnetic nanostructures and multilayered thin films at high lateral resolution down to 15nm by using Fresnel zone plates as X-ray optical elements. Magnetization reversal phenomena on a microscopic level are studied by recording the images in varying external magnetic fields. Local spin dynamics at a time resolution below 100ps can be addressed by engaging a stroboscopic pump-and-probe scheme taking into account the time pattern of synchrotron storage rings. Characteristic features of magnetic soft X-ray microscopy are reviewed and an outlook into future perspectives with regard to increased lateral and temporal resolution is given.

Images with a spatial resolution of 120-150 nm were obtained with 46.9 nm light from a compact capillary-discharge laser by use of the combination of a Sc-Si multilayer-coated Schwarzschild condenser and a free-standing imaging zone plate. The results are relevant to the development of compact extreme-ultraviolet laser-based imaging tools for nanoscience and nanotechnology.

Analytical tools that have spatial resolution at the nanometre scale are indispensable for the life and physical sciences. It is desirable that these tools also permit elemental and chemical identification on a scale of 10 nm or less, with large penetration depths. A variety of techniques in X-ray imaging are currently being developed that may provide these combined capabilities. Here we report the achievement of sub-15-nm spatial resolution with a soft X-ray microscope--and a clear path to below 10 nm--using an overlay technique for zone plate fabrication. The microscope covers a spectral range from a photon energy of 250 eV (approximately 5 nm wavelength) to 1.8 keV (approximately 0.7 nm), so that primary K and L atomic resonances of elements such as C, N, O, Al, Ti, Fe, Co and Ni can be probed. This X-ray microscopy technique is therefore suitable for a wide range of studies: biological imaging in the water window; studies of wet environmental samples; studies of magnetic nanostructures with both elemental and spin-orbit sensitivity; studies that require viewing through thin windows, coatings or substrates (such as buried electronic devices in a silicon chip); and three-dimensional imaging of cryogenically fixed biological cells.

As the development of extreme-ultraviolet (EUV) lithography progresses, interest grows in the extension of traditional optical components to the EUV regime. Because of the strong absorption of EUV by most materials and because of its extremely short wavelength, however, it is difficult to implement many components that are commonplace in the longer-wavelength regimes. One such example is the diffuser that is often implemented with ordinary ground glass in the visible light regime. Here we demonstrate the fabrication of reflective EUV diffusers with high efficiency within a controllable bandwidth. Using these techniques, we have fabricated diffusers with efficiencies exceeding 10% within a moderate angular single-sided bandwidth of approximately 0.06 rad.

We report on a novel series of biomimetic polymers exhibiting interfacial properties similar to the extracellular matrix. A series of well-defined surfactant polymers were synthesized by simultaneously incorporating arginine-glycine-aspartic acid (RGD) peptide, dextran oligosaccharide, and hexyl ligands with controlled feed ratios onto a poly(vinyl amine) (PVAm) backbone. The peptide sequence was H-GSSSGRGDSPA-NH(2) (Pep) having a hydrophilic extender at the amino terminus and capped carboxy terminus. The peptide-to-dextran (Pep:Dex) ratios were varied to create surfactants having 0, 25, 50, 75, and 100 mol-% peptide relative to dextran. The surfactants were characterized by IR, NMR and atomic force microscopy (AFM) for composition and surface active properties. AFM confirmed full surface coverage of PVAm(Pep)(100%) on graphite, and supported the mechanism of interdigitation of hexyl ligands between surfactant molecules within a specified range of hexyl chain densities. the attachment and growth of human pulmonary artery endothelial cells on the PVAm(Pep)(100%) surface was identical to the fibronectin positive control. Cell adhesion decreased dramatically with decreasing peptide density on the surfactant polymers. Molecular model of a peptide surfactant polymer, consisting of poly(vinyl amine) backbone with peptide, dextran oligosaccharide and hexyl branches coupled to the polymer chain.

Successful engineering of a tissue-incorporated vascular prosthesis requires cells to proliferate and migrate on the scaffold. Here, we report on a series of "ECM-like" biomimetic surfactant polymers that exhibit quantitative control over the proliferation and migrational properties of human microvascular endothelial cells (HMVEC). The biomimetic polymers consist of a poly(vinyl amine) (PVAm) backbone with hexanal branches and varying ratios of cell binding peptide (RGD) to carbohydrate (maltose). Proliferation and migration behavior of HMVEC was investigated using polymers containing RGD: maltose ratios of 100:0, 75:25 and 50:50, and compared with fibronectin (FN) coated glass (1 microg/cm2). A radial Teflon fence migration assay was used to examine HMVEC migration at 12 h intervals over a 48 h period. Migration was quantified using an inverted optical microscope, and HMVEC were examined by confocal microscopy for actin and focal adhesion organization/ arrangement. Over the range of RGD ligand density studied (approximately 0.19-0.6 peptides/nm2), our results show HMVEC migration decreases with increasing RGD density in the polymer. HMVEC were least motile on the 100% RGD polymer (approximately 0.38-0.6 peptides/nm2) with an average migration of 0.20 mm2/h in area covered, whereas HMVEC showed the fastest migration of 0.48+/-0.06 mm2/h on the 50% RGD surface ( approximately 0.19-0.30 peptides/nm2). In contrast, cell proliferation increased with increasing surface peptide density; proliferation on the 50% RGD surface was 1.5%+/-0.06/h compared with 2.2%+/-0.07/h on the 100% RGD surface. Our results show that surface peptide density affects cellular functions such as growth and migration, with the highest peptide density supporting the most proliferation but the slowest migration.

Cognitive representations of illness determine behavior. How persons living with AIDS image their disease might be key to understanding medication adherence and other health behaviors. The authors' purpose was to describe AIDS patients' cognitive representations of their illness. A purposive sample of 58 men and women with AIDS were interviewed. Using Colaizzi's (1978) phenomenological method, rigor was established through application of verification, validation, and validity. From 175 significant statements, 11 themes emerged. Cognitive representations included imaging AIDS as death, bodily destruction, and just a disease. Coping focused on wiping AIDS out of the mind, hoping for the right drug, and caring for oneself. Inquiring about a patient's image of AIDS might help nurses assess coping processes and enhance nurse-patient relationships.

We have imaged a 2D buried Ni nanostructure at 8 nm resolution using coherent x-ray diffraction and the oversampling phasing method. By employing a 3D imaging reconstruction algorithm, for the first time we have experimentally determined the 3D structure of a noncrystalline nanostructured material at 50 nm resolution. The 2D and 3D imaging resolution is currently limited by the exposure time and the computing power, while the ultimate resolution is limited by the x-ray wavelengths. We believe these results pave the way for the development of atomic resolution 3D x-ray diffraction microscopy.

The motion of electrons through quantum dots is strongly modified by single-electron charging and the quantization of energy levels. Much effort has been directed towards extending studies of electron transport to chemical nanostructures, including molecules, nanocrystals and nanotubes. Here we report the fabrication of single-molecule transistors based on individual C60 molecules connected to gold electrodes. We perform transport measurements that provide evidence for a coupling between the centre-of-mass motion of the C60 molecules and single-electron hopping--a conduction mechanism that has not been observed previously in quantum dot studies. The coupling is manifest as quantized nano-mechanical oscillations of the C60 molecule against the gold surface, with a frequency of about 1.2 THz. This value is in good agreement with a simple theoretical estimate based on van der Waals and electrostatic interactions between C60 molecules and gold electrodes.

We use electrostatic force microscopy and scanned gate microscopy to probe the conducting properties of carbon nanotubes at room temperature. Multiwalled carbon nanotubes are shown to be diffusive conductors, while metallic single-walled carbon nanotubes are ballistic conductors over micron lengths. Semiconducting single-walled carbon nanotubes are shown to have a series of large barriers to conduction along their length. These measurements are also used to probe the contact resistance and locate breaks in carbon nanotube circuits.