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Depression contributes to persistent opioid analgesic use (OAU). Treating depression may increase opioid cessation.
To determine if adherence to antidepressant medications (ADMs) v. non-adherence was associated with opioid cessation in patients with a new depression episode after >90 days of OAU.
Patients with non-cancer, non-HIV pain (n = 2821), with a new episode of depression following >90 days of OAU, were eligible if they received ≥1 ADM prescription from 2002 to 2012. ADM adherence was defined as >80% of days covered. Opioid cessation was defined as ≥182 days without a prescription refill. Confounding was controlled by inverse probability of treatment weighting.
In weighted data, the incidence rate of opioid cessation was significantly (P = 0.007) greater in patients who adhered v. did not adhered to taking antidepressants (57.2/1000 v. 45.0/1000 person-years). ADM adherence was significantly associated with opioid cessation (odds ratio (OR) = 1.24, 95% CI 1.05–1.46).
ADM adherence, compared with non-adherence, is associated with opioid cessation in non-cancer pain. Opioid taper and cessation may be more successful when depression is treated to remission.
A rare subclass of Type Ia supernovae (SNe Ia) shows evidence of strong interaction with a hydrogen-rich circumstellar medium (CSM); these objects are referred to as SNe Ia-CSM. PTF11kx began life as a SN Ia, but after a month it began to show indications of significant interaction with its CSM. This well-studied object solidified the connection between SNe Ia-CSM and more typical SNe Ia, despite their spectral similarity to Type IIn SNe (which likely come from massive star progenitors, as opposed to the white dwarf progenitors for the SNe Ia-CSM). The spectra of all ~20 known SNe Ia-CSM are dominated by Hα emission (with widths of ~2000 km s−1) and exhibit large Hα/Hβ intensity ratios; moreover, they have an almost complete lack of He I emission (see left panel of Figure 1). They also show possible evidence of dust formation through a decrease in the red wing of Hα 75–100 days past maximum brightness. The absolute magnitudes of SNe Ia-CSM are found to be -21.3 mag ≤ MR ≤ −19 mag (see right panel of Figure 1), and they also show ultraviolet emission at early times and strong infrared emission at late times (but no detected radio or X-ray emission). Finally, the host galaxies of SNe Ia-CSM imply that these objects come from a relatively young stellar population.
As a product of natural selection, pain behavior must serve an adaptive function for the species beyond the accurate portrayal of the pain experience. Pain behavior does not simply refer to the pain experience, but promotes survival of the species in various and complex ways. This means that there is no purely respondent or operant pain behavior found in nature.
Knowledge of the mechanical properties of interlevel dielectric films and their impact on sub-micron interconnect reliability is becoming more and more important as critical dimensions in ULSI circuits are scaled down. For example, lateral aluminum (Al) extrusions into spaces between metal lines, which become a more of a concern as the pitches shrink, appear to depend partially on properties of SiO2 underlayers. In this paper, the mechanical properties of several common interlevel dielectric SiO2 films such as undoped silica glass using a silane (SiH4) precursor, undoped silica glass using a tetraethylorthosilicate (TEOS) precursor, phosphosilicate glass (PSG) deposited by plasma-enhanced chemical vapor deposition (PECVD) and borophosphosilicate glass (BPSG) deposited by sub-atmosphere chemical vapor deposition (SACVD) were studied. Among the four common interlevel layers, BPSG exhibits the smallest modulus (E), hardness (H) and the highest the coefficients of thermal expansion (CTE). BPSG again has the lowest as-deposited compressive stress and the lowest local Si-O-Si strain before annealing. Stress interactions between the various SiO2 underlayers and the Al metal film are further investigated. The impact of dielectric elastic properties on interconnect reliability during thermal cycles is proposed.
Chlorine-containing precursors are attractive for chemical vapor deposition (CVD) of SiC because they are less hazardous and more economical than silane precursors. The reactivity of HCl, a by-product of these reactions, on SiC is of particular interest because it has been reported that HCl inhibits SiC CVD, but the mechanism for this inhibition has not been identified. In this work the adsorption of HCl on polycrystalline β-SiC was examined with Auger Electron Spectroscopy (AES) and Temperature Programmed Desorption (TPD). HCl adsorbs readily on SiC, with an initial sticking probability of 0.1 at 300 K, and forms a strong bond, with an activation energy for desorption of 64 kcal/mol. The only product detected by TPD is HCl, which desorbs in a peak centered at 1010 K. There are no Si- or C-containing desorption products, demonstrating that HCl does not etch SiC under TPD conditions. These results are consistent with a site-blocking mechanism for HCl inhibition of SiC CVD, but not with an etching mechanism.
Measurements of the decomposition of mixtures of boron trichloride (BCl3), titanium tetrachloride (TiCl4), and hydrogen at elevated temperatures are presented. The decomposition of BCl3 with hydrogen appears to drive the chemistry in this system. The species depositing boron on the surface contains at least 2 chlorine atoms. Once deposited, the surface chlorine is removed by reaction with hydrogen to form HCl and, presumably, surface B-H bonds.
Since NH3 is an important component of TiN chemical vapor deposition (CVD) processes, understanding the NH3/TiN surface interaction is crucial to developing a model for the overall reaction. Temperature programmed desorption experiments show that NH3 adsorbs molecularly on amorphous TiN surfaces. Chemisorption occurs at only ∼5% of the surface sites, with an activation energy for desorption of 24 kcal/mol. The sticking probability into this state is 0.06 at 100 K. In addition, NH3 adsorbs with high probability into a multilayer state with an activation energy for desorption of 7.3 kcal/mol, similar to that found in other systems. NH3 does not dissociate on TiN. Under CVD conditions, however, the reactivity of NH3 on TiN may increase and surface reactions may play a part in film growth.
The kinetics of gas-phase reactions occurring during the CVD of boron nitride (BN) from BCl3 and NH3 are investigated using an elementary reaction mechanism whose rate constants were obtained from theoretical predictions and literature sources. Plug-flow calculations using this mechanism predict that unimolecular decomposition of BCl3 is not significant under typical CVD conditions, but that some NH3 decomposition may occur, especially for deposition occurring at atmospheric pressure. Reaction of BCl3 with NH3 is rapid under CVD conditions and yields species containing both boron and nitrogen. One of these compounds, Cl2BNH2, is predicted to be a key gas-phase precursor to BN.