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Though theory suggests that individual differences in neuroticism (a tendency to experience negative emotions) would be associated with altered functioning of the amygdala (which has been linked with emotionality and emotion dysregulation in childhood, adolescence, and adulthood), results of functional neuroimaging studies have been contradictory and inconclusive. We aimed to clarify the relationship between neuroticism and three hypothesized neural markers derived from functional magnetic resonance imaging during negative emotion face processing: amygdala activation, amygdala habituation, and amygdala-prefrontal connectivity, each of which plays an important role in the experience and regulation of emotions. We used general linear models to examine the relationship between trait neuroticism and the hypothesized neural markers in a large sample of over 500 young adults. Although neuroticism was not significantly associated with magnitude of amygdala activation or amygdala habituation, it was associated with amygdala–ventromedial prefrontal cortex connectivity, which has been implicated in emotion regulation. Results suggest that trait neuroticism may represent a failure in top-down control and regulation of emotional reactions, rather than overactive emotion generation processes, per se. These findings suggest that neuroticism, which has been associated with increased rates of transdiagnostic psychopathology, may represent a failure in the inhibitory neurocircuitry associated with emotion regulation.
Associations between high body mass index (BMI) and subsequent cognitive decline, reported in elderly averaging below age 75, become less consistent at older ages. We compared the associations of BMI with cognition in moderately old (ages 75–84, N = 154) and oldest-old (85+, N = 93) samples. BMI and cognition were assessed cross-sectionally in cognitively intact elderly (mean age = 84.5, SD = 4.4) male veterans. Regression analyses of three cognitive domains — executive functions/language, attention, and memory—compared relationship with BMI between the moderately old and oldest-old. Higher BMI was associated with relatively poorer executive functions/language performance in the moderately old, while the opposite relationship, higher BMI associated with relatively better performance, was found in the oldest-old. Associations for the other two cognitive domains did not differ significantly between age groups. The reversal of association direction for executive functions/language performance with higher BMI is consistent with the protected survivor model. This model posits a minority subpopulation with a protective factor—genetic or otherwise—against both mortality and cognitive decline associated with risk factor status. The very old who remain cognitively intact despite the presence of risk factors are more likely to possess protection.
Background: The incidence of brain metastases is increasing with the development of improved systemic therapies with limited impact on intracranial disease. The purpose of this study was to determine if there is a threshold tumor size below which local control (LC) rates approach 100% after stereotactic radiosurgery (SRS). Methods: 200 patients with 1237 tumors were identified from a prospective registry of patients having undergone SRS between 2012-2014. Histology consisted predominantly of non-small cell lung cancer (NSCLC), melanoma and breast cancer. Results: The median tumor size was 6 mm in diameter or 70 mm3 and most commonly NSCLC. Thirty-three tumors had local progression at a median time of 8.8 months. The 1- and 2-year actuarial LC for all tumors were 97% and 93%. LC of 100% was seen for intracranial metastases less than 100 mm3 or 6 mm in diameter, independent of histology. Total tumor volume was an independent predictor of overall survival, after adjusting for age, KPS and extracranial disease status. Conclusions: SRS can achieve LC rates approaching 100% for subcentimeter metastases. The earlier detection and prompt treatment of small intracranial metastases may prevent the development of neurological symptoms, the need for surgical resection, and potentially improve overall survival. The results of this study would favour the implementation of routine staging MRIs.
This study aimed to identify risk factors associated with carbapenem-resistant Enterobacteriaceae (CRE) colonization among patients screened with rectal cultures upon admission to a hospital or long-term acute care (LTAC) center and to compare risk factors among patients who were screen positive for CRE at the time of hospital admission with those screen positive prior to LTAC admission.
A retrospective nested matched case-control study was conducted from June 2009 to December 2011. Patients with recent LTAC exposure were screened for CRE carriage at the time of hospital admission, and patients admitted to a regional LTAC facility were screened prior to LTAC admission. Cases were patients with a positive CRE screening culture, and controls (matched in a 3:1 ratio to cases) were patients with negative screening cultures.
Nine hundred five cultures were performed on 679 patients. Forty-eight (7.1%) cases were matched to 144 controls. One hundred fifty-eight patients were screened upon hospital admission and 521 prior to LTAC admission. Independent predictors for CRE colonization included Charlson's score greater than 3 (odds ratio [OR], 4.85 [95% confidence interval (CI), 1.64–14.41]), immunosuppression (OR, 3.92 [95% CI, 1.08–1.28]), presence of indwelling devices (OR, 5.21 [95% CI, 1.09–2.96]), and prior antimicrobial exposures (OR, 3.89 [95% CI, 0.71–21.47]). Risk factors among patients screened upon hospital admission were similar to the entire cohort. Among patients screened prior to LTAC admission, the characteristics of the CRE-colonized and noncolonized patients were similar.
These results can be used to identify patients at increased risk for CRE colonization and to help target active surveillance programs in healthcare settings.
We used mandatory public reporting as an impetus to perform a statewide study to define risk factors for surgical site infection. Among women who underwent abdominal hysterectomy, blood transfusion was a significant risk factor for surgical site infection in patients who experienced blood loss of less than 500 mL.
Son preference has been considered as a determinant of women's risk of intimate partner violence (IPV) experience in India, although quantitative evidence from large nationally representative studies testing this relationship is limited. This study examines the association between husband's son preference, sex composition of children and risk of physical and sexual IPV victimization among wives. Information was collected for 26,284 couples in the nationally representative 2005–2006 National Family Health Survey of India. The exposures were husband's son preference measured as husband's desire for one or more sons greater than the number of daughters and sex composition of the household: only sons, only daughters and mixed. Outcome included past year physical and/or sexual IPV. The results showed that husband's reported son preference (RR: 1.05; 95% CI: 0.98–1.13) and sex composition of children were not associated with risk for IPV victimization in the models adjusted for socio-demographic factors. The findings from this first population-based study of socio-cultural norms around son preference and married Indian women's risk for IPV victimization indicate that cultural preference for sons does not influence women's risk for IPV victimization.
Polydimethylsiloxane [PDMS]-modified SiO2-TiO2, glasses have been prepared via the sol-gel route. Polymer compositions varied between 17 and 67 wt% PDMS, using PDMS of molecular weights 1,700 and 36,000. Also varied was the Si/Ti ratio for a given polymer content and the nature of the Ti alkoxide.A general synthetic procedure was found which made optically clear samples. Dense monolithic structures were obtained at room temperature for all compositions. The room temperature densification is attributed to relaxation and flow in the sample due to the presence of the polymer. The effects on properties of the overall composition and molecular weight of the polymer are reported, and implications in terms of structural models are considered.
Electrical characterization of MOS structures and device modeling require accurate information about dopant concentration, particularly at the poly-Si/SiO2 interface. We compare four experimental techniques (secondary ion mass spectrometry SIMS, resonant ion mass spectrometry RIMS, differential Hall effect profiling, and spreading resistance analysis) to measure boron and free carrier concentrations in poly-Si, SiO2 and crystalline Si. We find that no single technique completely characterizes the entire MOS structure, and that spreading resistance analysis in particular substantially underestimates the free carrier concentration at the poly-Si/SiO2 interface. We conclude that in most cases of technological interest the magnitude of the poly depletion effect scales with the average carrier concentration at some distance away from the interface and that the interfacial effects, such as dopant segregation, are of only secondary importance. These findings are supported by theoretical modeling of capacitance-voltage behavior of boron-doped MOS capacitors.
ESCA studies of two molecules which are similar in structure to the PMDA and ODA constituents of the PMDA-ODA polyimide monomer are discussed. Their interaction with in-situ evaporated Cr and Cu films are compared. The PMDA model compound interacts with Cr through the imide group, while very little interaction is observed with Cu. The ODA model compound (oxydianiline) interacts with Cr via the ether linkage and the terminal amino groups, whereas very little interaction is observed with Cu.
XPS data obtained during the initial stages of vapor deposition of chromium atoms onto a PMDA-ODA polyimide substrate is presented. Utilizing the results of molecular orbital calculations it is emphasized that the data is consistent with the formation of a charge transfer complex between the deposited metal atoms and the PMDA unit of the polymer.
Lateral dopant diffusion is a well known problem in dual-gate W-polycide CMOS devices. We have recently demonstrated that RTA processing helps to alleviate this problem and at the same time ensures sufficient dopant activation. However, due to the complex micro-structural changes in both poly-Si and WSix (x˜2.5) layers during the RTA process, the time dependence of the diffusion processes and dopant distribution are difficult to predict. Consequently, the process optimization and device simulations are rather unreliable. We describe a new experimental technique to measure lateral dopant diffusion and 2-dimensional dopant distribution in RTA processed W-polycide structures using conventional SIMS analysis of lithographically defined test structures. Our experiments show that the technique is capable of measuring lateral dopant diffusion over distances between one and tens of microns without losing the vertical resolution of conventional SIMS profiling. The technique can be used to study diffusion processes in a variety of materials and multi-layer structures.
By using a combination of smooth epi substrates (0.7 Å rms roughness),
in-situ UV/Cl2 processing, and rapid thermal oxidation, highly
reliable ultrathin gate oxides were produced with ≤ 1.0 Å rms interface
Deep submicron CMOS technology for low-power, low-voltage applications requires the use of symmetric n+/p+ poly gate structures. This requirement introduces a number of processing challenges, involving fundamental issues of atomic diffusion over distances of 1Å to ∼30μm. Two of the critical issues are dopant cross-diffusion between P- and NMOS devices with connected gates, resulting in large threshold voltage shifts, and boron penetration through the gate oxide. We show that in devices with W-polycide dual-gat:e structure most of these problems can be alleviated by using rapid thermal annealing, RTA, in combination with a few additional, simple processing steps (e. g., low-temperature recrystallization of a-Si layer and selective nitrogen coimplants). The RTA step, in particular, ensures thai: the boron activation in the p+ poly-Si remains high and negates any effects of arsenic cross-diffusion. CMOS devices with properly processed gates have low gate stack profiles, small threshold voltage shifts (<30mV), and excellent device characteristics.
An understanding of dielectric breakdown mechanisms is critical for continued oxide scaling. Although working transistors have been demonstrated with sub-2nm SiO2 gate dielectrics, the manufacturability of such devices hinges on the reliability of the oxide. As oxides become thinner and operating voltages become lower, a fundamentally different mode of dielectric breakdown occurs. This has been called soft breakdown and is considered to be the formation of a small, localized tunneling path through a dielectric. For transistors with 2-nm gate oxides, threshold voltage and maximum transconductance are not affected by soft breakdown, implying that circuits may continue to operate after soft breakdown. The increase in gate current or voltage noise associated with soft breakdown is not a limiting factor for many applications. However, some cases will be shown in which soft breakdown does degrade device function.
In order to make comparisons of ultra-thin oxide quality, it is important to be able to reliably detect soft breakdown. J-ramp, a commonly used ramped-current measurement to determine oxide quality, is unable to detect soft breakdown in ultra-thin oxides. We will demonstrate the incorporation of noise measurements in a commercial J-ramp algorithm.
In the past, coronary arterial anomalies have been difficult to diagnose by non-invasive methods. Identification of coronary arterial origins is now a routine part of the standard paediatric echocardiogram. Anomalous origin of a coronary artery from the pulmonary trunk is an extremely important diagnosis to make. Many echocardiographic features are not directly related to the visualisation of the coronary arterial origin. Left ventricular dilation and abnormal ventricular performance are common, along with mitral regurgitation and evidence of collateralisation of the flow from the coronary artery that has an aortic origin. In some cases, the anomalous coronary artery can be seen to arise directly from the pulmonary trunk. Congenital atresia of the main stem of the left coronary artery has a similar echocardiographic presentation, except that its aortic origin is not determined. Anomalous aortic origin of the coronary artery has important implications, as the first presenting symptom can be sudden death. With meticulous attention to the origins of the coronary arteries, echocardiographic diagnosis can also be achieved. In contrast to the anomalous origin of a coronary artery from the pulmonary trunk, ventricular performance is usually normal. Whenever there is doubt as to the definition of the origin of the coronary arteries and, indeed, when there is serious clinical concern that a coronary artery has an anomalous origin, other testing, such as cine-computed tomography, magnetic resonance imaging, or cardiac catheterisation may be indicated for confirmation or to provide greater anatomic detail.