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A condensed phase of zirconium monoxide (ZrO) was detected in YSZ (Zr_(0.92)Y_(0.08)O_(2-δ)) coatings deposited using plasma spray-physical vapor deposition. The rapid cooling rate of this process can result in the condensation of nonequilibrium states that can be kinetically trapped in the coatings. The columnar microstructure contained a mixture of YSZ, ZrO2, and ZrO phases. The ZrO phase was expected to be conductive based on density functional theory calculations, and preliminary impedance measurements were performed that supported this prediction. When heated in an oxygen-containing environment, the ZrO phase remains in the coating until ∼450 K, at which point it disappears quickly, as confirmed by X-ray diffraction and thermogravimetric methods. The loss of ZrO in the coating was also linked to a loss in electrical conductivity. However, it was shown that this phase can persist at elevated temperatures of ∼1000 K in vacuum or inert environments for at least 100 h.

Review of: Beyond the Hills (2012) Romania Director Cristian Mungiu Runtime 152 minutes

If policy preferences follow material interests, the experience of socioeconomic disadvantage ought to increase support for redistributive policies. However, experiencing disadvantage might also reduce faith in government’s ability to make things better, indirectly reducing support for redistributive action, and leading to a spiral of widening disadvantage and increasing political disengagement. Indeed, disadvantaged communities sometimes favour right-wing platforms over those offering redistribution, as in the taking of ‘red wall’ constituencies in the North and Midlands of England by the UK Conservative party in 2019. This article uses quantitative data from a survey of ‘red wall’ voters (n = 805) to examine the bases of people’s perceptions of redistributive policies. We find that even a radical redistributive policy, Universal Basic Income (UBI), receives consistently high levels of support (69.45 SD 27.24). Lower socioeconomic status, greater financial distress and greater risk of destitution all increase support. These effects are partly mediated by mental distress, which is markedly higher among the less well off. However, the same socioeconomic factors also reduce faith in government, which in turn is associated with lower support. Thus, those who stand to benefit most from redistribution are aware of their material interests, but are also the least confident in the ability of government to improve their lives. As such, there is a clear political challenge for progressive politicians: those whose support they depend upon require a significant redistributive offer, but also need to be persuaded of the viability of reform to support progressive change.

The time-domain thermoreflectance metrology is applied to evaluate the thermal conductivities of filler particles embedded in a composite matrix. Specifically, a system of glass and ceramic microspheres with a diameter of 100 to 150 μm embedded in an epoxy matrix was used as a representation of a typical composite thermal interface material (TIM) suitable for microelectronics applications. These measurements provide a direct characterization of the thermal properties of filler materials. The measured thermal conductivities of both borosilicate glass and yttria stabilized zirconia microspheres agree well with literature values for bulk materials, whereas the thermal conductivity of the alumina microspheres is nearly 50% lower than that of bulk crystals. The reduction in thermal conductivity of the alumina microspheres highlights how important this level of understanding is for TIM development and is attributed to enhanced phonon scattering due to structural heterogeneity, such as defects induced by phase mixing and microvoids. Combining sample preparation, structural characterization, and direct thermal measurements, our study reveals the structure–thermal property relationship for individual microspheres. The results of this work can facilitate the design and engineering of composite-based thermally conductive materials for thermal management applications.

We show that optical coupling can be achieved reproducibly and with high yield by resonance tuning the elements of substrate-emitting and top-emitting vertical-cavity surface-emitting laser arrays. The resonance tuning is enabled by electrical isolation of the lasing elements in the array, which in this paper is done by post fabrication processing. Prior to electrical isolation, the laser arrays exhibit incoherent optical properties. Using resonance tuning, both in-phase and out-of-phase coherent modes are observed.

A grain-selection template was applied to freeze casting to control nucleation of pore-forming crystals and achieve ceramics with highly aligned pore structures. A polymethylsiloxane preceramic polymer was freeze cast with cyclohexane as a solvent to produce dendritic pores in SiOC. Image analysis and permeability measurements were performed to quantify the influence of various templates on sample properties. Results show that the percentage of porosity aligned along the freezing axis increased from 13.9% without a template to 92.6% with an optimal template. The Darcian permeability constant increased by more than 6-fold, from 3.4 × 10^(−12) to 2.1 × 10^(−11) m^2.

Progress has been made in applying genetic information to disease management in the postgenomic era, and precision medicine is emerging in prostate cancer management. The prostate health index, the 4-kallikrein (4K) score, and the PCA3, TMPRSS2- ERG, and Prostarix tests have potential for refining prostate cancer screening in conjunction with traditional prostate-specific antigen testing. The Confirm MDx and PCA3 tests have shown promise in identifying men who need be rebiopsied after a primary negative biopsy. Oncotype DX, Prolaris, the biopsy-based Decipher prostate cancer test, and ProMark may improve predictive risk stratification in addition to the traditional Gleason score and tumor stage. Decipher and Prolaris may predict biochemical recurrence and metastasis after radical prostatectomy and possibly help identify patients who need adjuvant therapy. Androgen receptor splice variant 7 appears effective in guiding the selection of second hormonal manipulation with abiraterone or enzalutamide versus chemotherapy when treating metastatic castration-resistant prostate cancer.

Coupled semiconductor laser arrays are naturally non-Hermitian optical systems. We show that in a weakly coupled semiconductor laser array, the control for gain/loss is dominated by the nonlinearities, rather than simply following the pump profile.

Vertical-cavity surface-emitting laser arrays can be designed to operate in a coherently coupled mode, however, high yield has been challenging in past efforts. We discuss microcavity laser arrays that are designed to be optically coupled but with independent bias current injection into each array element. We demonstrate that these arrays can be electronically tuned to coherently coupled operation and at bias conditions not previously realized. Control of injection bias conditions to individual array elements allows resonance tuning of each element with the result that the phase relation and coherence of the array can be engineered. This control enables increased output power in either in-phase or out-of-phase coherent operation from a single array, and ensures coherent operation from nearly all arrays. This ability to tune into coherence will enhance the performance of phased vertical cavity laser arrays as well as improve their fabrication yield.

We show a significant improvement of modulation bandwidth from $2\times 1$ photonic crystal vertical-cavity surface-emitting laser arrays. Control of injection bias conditions to array elements enables resonance tuning of each element with variation of the phase relation and coherence of the array, resulting in the ability to tailor the modulation response. A bandwidth of 37 GHz is obtained under highly single-mode coherent operation with narrow spectral width and increased output power while the laser array is biased at low current density. Lasers with such performance characteristics may greatly enhance high-rate data transfer in computer server, data center, and supercomputer applications with potentially long device lifetime.

Two-dimensional coherently coupled photonic crystal ion-implanted bottom emitting vertical cavity surface emitting laser arrays are demonstrated. Subthreshold luminescence shows uniform current injection below threshold, benefiting from the improved contact alignment compared with the top emitting arrays. In-phase operation has been achieved in $2\times 2$ and $3\times 3$ arrays at lasing threshold. A remaining challenge is achieving uniform current distribution above lasing threshold for larger arrays due to the variation of series resistance through each of the elements of the arrays.

Positive surgical margins (PSMs) may reflect incomplete surgical resection, while extraprostatic extension (EPE) could suggest that complete tumor resection is more difficult. This study evaluated cases with both EPE and PSMs in robotic-assisted radical prostatectomy (RARP) specimens to determine the respective locations of each. A single institutional retrospective review of RARP performed between 2007 and 2009 was conducted to identify cases with both EPE and PSM. Prostates were entirely submitted and processed in whole mount format. All locations of EPE and PSM were recorded as was the size of the largest focus of EPE and PSM. About 8.5 % (112/1,315) of RARP had both EPE and PSM. Analysis of cases with concurrent EPE and PSM revealed that EPE occurred most commonly in the mid-gland, particularly in the posterolateral mid-prostate. In contrast, PSM was most frequent at the base (bladder neck), specifically the anterior base. 51.8 % of the cases had EPE and PSM in discordant locations, 19.6 % had EPE and PSM in the same location, and 28.6 % had areas of EPE and PSM both in the same location as well as in different locations. Cases with both concordant and discordant locations of EPE and PSM had significantly more high-risk features including higher tumor volume, more frequent positive nodes, and more frequent Gleason score ≥ 8 compared to concordant or discordant subgroups. PSMs frequently did not occur in the same location as EPE. A better understanding of where EPE and PSMs occur may help guide surgical technique to decrease residual tumor.

The PolyScope(®) (Lumenis, Santa Clara, CA) is a disposable flexible ureteroscope composed of a single-use flexible catheter and a reusable fiber optic bundle. We tested the resilience of the optical properties of the reusable optical fiber after repeat sterilization.Optical properties evaluated were resolution, distortion, and light transmission. Two different optical fibers were tested, one for each sterilization method. Measurements on each fiber were obtained at baseline and were repeated after each set of 10 sterilization cycles for a total of 100 cycles. To measure resolution, the 1951 USAF Contrast Resolution Chart Target was used to subjectively identify the clearest image on the grid by two different operators. To measure distortion, three images of the distortion grid target were captured with a digital camera and analyzed within Image Pro Plus Software. Light transmission was measured using a digital light meter at 50% and 100% transmission.There was no significant difference in resolution after 100 sterilization cycles between either Steris or Sterrad NX. Distortion changed by 8.7% and 11.2% for Steris and Sterrad NX, respectively. For Steris at 100% light transmission, baseline was 59 foot-candles and this increased to 85 foot-candles after 100 cycles. For Sterrad NX at 100% light transmission, baseline was 50 foot-candles and this increased to 92 foot-candles after 100 cycles. Results were similar at 50%. There was no significant difference between groups at 50%, 100%, or between sterilization modalities.The PolyScope fiber optic bundle appears durable after 100 cycles of sterilization with either Steris or Sterrad NX.

Coherently coupled vertical cavity laser arrays are modeled using dynamic coupled mode theory. Beam steering, mode evolution and hopping are predicted using parity-time symmetry considerations. Mode evolution and hopping with hysteresis is reported and compared with theory and shows quantitative agreement.

High immunohistochemical expression of carbonic anhydrase IX (CAIX) is found in clear cell renal cell carcinoma (ccRCC), but no studies have assessed CAIX in metastatic ccRCC (mccRCC) of the lung. As 75% of patients with mccRCC show lung involvement, characterization of protein expression in these lesions is warranted. This investigation analyzed CAIX immunohistochemical expression in pulmonary/pleural tumors including mccRCC (n = 22), mesothelioma (n = 19), squamous cell carcinoma (n = 27), small cell carcinoma (n = 9), and adenocarcinoma (n = 49), as well as other mesothelial lesions (n = 4). Membranous immunoreactivity was semiquantitatively evaluated for percent of cells stained and intensity. All cases of mccRCC (1+, 4.5%; 3+, 95.5%) and mesothelioma (2+, 10.5%; 3+, 89.5%) expressed CAIX. Most cases of lung squamous cell carcinoma (0, 11.1%; 1+, 25.9%; 2+, 22.2%; 3+, 40.7%) and small cell carcinoma were reactive (0, 11.1%; 1+, 22.2%; 2+, 33.3%; 3+, 33.3%), while CAIX was detected less frequently in pulmonary adenocarcinoma (0, 61.2%; 1+, 16.3%; 2+, 12.2%; 3+, 10.2%). In addition, CAIX was positive in adenomatoid tumor (3+, 100%) and mesothelial hyperplasia (3+, 100%). We demonstrate that CAIX is sensitive for mccRCC within the lung and a novel immunohistochemical marker for mesothelial proliferations, notably mesothelioma. Variable immunoreactivity is present among primary pulmonary epithelial tumors. Knowledge of expression overlap between these entities may prevent an incorrect interpretation of immunohistochemical results, particularly when limited tissue is available. As new carbonic anhydrase inhibitors are being evaluated, testing additional tumors for CAIX may lead to novel treatment options.

Donato D P, Johnson M T, Yang X J & Zynger D L (2011) Histopathology 59, 1229–1239 Expression of carbonic anhydrase IX in genitourinary and adrenal tumours Aims: High expression of carbonic anhydrase IX (CAIX) is reported for clear cell renal cell carcinoma (RCC), with a paucity of data for non-renal genitourinary or adrenal tumours. This study investigated the immunohistochemical expression of CAIX throughout the genitourinary tract and adrenal gland. Methods and results: High expression in the renal cortex was restricted to clear cell, papillary and clear cell papillary RCC and carcinoid. Core biopsies of clear cell RCC were consistently positive. Positivity within the urothelial tract was seen in urothelial carcinoma including squamous, small-cell, sarcomatoid and adenomatous differentiation and clear cell adenocarcinoma. Signet ring and plasmacytoid variants of urothelial carcinoma were negative. Phaeochromocytoma, adrenal cortical adenoma, seminoma, yolk sac tumour, choriocarcinoma, Leydig cell tumour and prostatic adenocarcinoma were predominately negative, with variable reactivity in adrenal cortical carcinoma, embryonal carcinoma, teratoma and Sertoli cell tumour. Conclusions: Carbonic anhydrase IX is a sensitive marker for clear cell RCC in core biopsies. However, other genitourinary or adrenal tumours that can have a clear cell appearance including urothelial, squamous cell, clear cell adeno and adrenal cortical carcinoma and Sertoli cell tumour express CAIX. Knowledge of expression overlap between these entities may prevent incorrect interpretation of immunohistochemical results, particularly if limited tissue is available.

We report on an optically pumped vertical-external-cavity surface-emitting laser array exhibiting coherent coupling. Imaging of the far field shows interference consistent with in-phase coherent coupling, and a majority of total power is present in the central on-axis lobe. The physical mechanism of operation is attributed to diffractive coupling, wherein a small portion of the light emitting from each emitter is shared with adjacent emitters of the array.

Prostate cancer is a cause of significant morbidity and mortality in men. Endogenous levels of androgen, produced by the testis and adrenal gland, have a complex and controversial role in the development and progression of prostate cancer. Androgen deprivation therapy (ADT) is a common treatment for prostate cancer, particularly in metastatic tumor cases and in certain cases of locally advanced disease. This paper reviews the surgical and medical options used to produce androgen blockade. Bilateral orchiectomy is the historic gold standard with fewer side effects than medical castration, although currently less frequently utilized. Gonadotropin releasing hormone (GnRH) agonists are the most commonly used medications for achieving castration. Other medications include estrogens, GnRH antagonists, steroidal and non-steroidal anti-androgens and 5-alpha reductase inhibitors. The advantages and side effects of each type of medication are described. Intermittent therapy and continuous androgen deprivat...

Recently groups reached differing conclusions when examining the prognostic significance of renal cell carcinoma perinephric and sinus fat invasion. We evaluated the impact of these pathological features on renal cell carcinoma survival and recurrence.We identified the pathological and clinical records of 110 patients treated surgically for renal cell carcinoma with extrarenal extension at our institution between 1997 and 2007. Patients with von Hippel-Lindau disease were excluded from study. We used Kaplan-Meier survival curves with the log rank statistic to evaluate differences between groups. Cox logistic regression analysis was used to control for metastatic disease, tumor size and renal vein involvement to determine differences among the groups.Patients with perinephric plus sinus fat invasion had worse cancer specific survival than those with perinephric or sinus fat invasion alone (p0.005). There was no difference in cancer specific survival between those with sinus vs perinephric fat invasion (p = 0.248). On multivariate analysis perinephric plus sinus fat invasion was a significant prognostic factor for death from renal cell carcinoma compared to sinus fat invasion alone (p = 0.038).Patients with combined renal sinus and perinephric fat invasion had a worse prognosis than those with either alone. Considerations should be made to stage these cases accordingly.

BACKGROUND: This study was undertaken to evaluate the accuracy of touch preparation (touch prep) in the evaluation of sentinel lymph nodes (SLNs). METHODS: We performed a retrospective review of 402 breast cancer patients who underwent SLN biopsy. RESULTS: A SLN was identified in 381 patients. Of 61 patients with a true positive result, 59 underwent axillary node dissection, and in 22 the SLN was the only node with metastases. Thirty-six (9.44%) had at least 1 false negative result. Twenty-five with a false negative results were due to macrometastases, with 17 (2.4%) false negatives occurring in patients with invasive ductal and 6 (5.5%) in those with invasive lobular histology, P = .04. Touch prep had an overall sensitivity of 62.89% and specificity of 98.94%. CONCLUSIONS: Touch prep for the evaluation of SLNs in breast cancer compares favorably to reported results for frozen section. False negative findings are more likely with micrometastases and invasive lobular histology.

Optically coupled semiconductor laser arrays are described by coupled rate equations. The coupled mode equations and carrier densities are included in the analysis, which inherently incorporate the carrier-induced nonlinearities including gain saturation and amplitude-phase coupling. We solve the steady-state coupled rate equations and consider the cavity frequency detuning and the individual laser pump rates as the experimentally controlled variables. We show that the carrier-induced nonlinearities play a critical role in the mode control, and we identify gain contrast induced by cavity frequency detuning as a unique mechanism for mode control. Photon-mediated energy transfer between cavities is also discussed. Parity-time symmetry and exceptional points in this system are studied. Unbroken parity-time symmetry can be achieved by judiciously combining cavity detuning and unequal pump rates, while broken symmetry lies on the boundary of the optical locking region. Exceptional points are identified at the intersection between broken symmetry and unbroken parity-time symmetry.

Sentinel lymph node biopsy (SLNB) has become the standard of care in axillary staging of clinically node-negative breast cancer patients. We hypothesized that certain clinical parameters are associated with failure to identify a SLN.We performed an institutional review board-approved, retrospective analysis of 402 consecutive breast cancer patients who underwent SLNB from 2000 to 2007.Of 402 patients, 399 had lymphoscintigraphy (LSG) performed at the time of radiocolloid injection. No significant differences in successful identification of a SLN were found with respect to patient age, histology, or pathologic status of the SLN. Thirteen of 27 patients with no nodes imaged on LSG failed to have a SLN identified at surgery, whereas only 8 of 372 patients with positive imaging on LSG failed to have a SLN identified at surgery (P.0001). Patients with a body mass index (BMI)or =40 had a significantly higher rate of failure to detect a SLN by LSG (5/29 patients) compared with patients with a normal BMI (4/145 patients; P.01). There was a trend for association with increasing BMI and failure to identify a SLN at surgery. The rate of failure to identify a SLN demonstrated a significant improvement in LSG after 200 patients and in surgical success after 100 patients (P.001).Successful identification of a SLN was influenced by BMI, institutional experience, and successful imaging by LSG. After gaining appropriate experience, the probability of successfully identifying a SLN at the time of surgery in a patient with BMI40 who imaged on LSG was 99.7%.

We demonstrate that photonic crystal anti-guided VCSEL arrays can be tuned to coherent operation by control of the cavity resonance by independent control of the bias currents.

In this study, FTIR spectroscopy and solid-state magic angle spinning (MAS) NMR were used to investigate the adsorption and thermal reaction of the nerve gas simulant dimethyl methylphosphonate (DMMP) in nanocrystalline NaY with a crystal size of approximately 30 nm. DMMP adsorbs molecularly in nanocrystalline NaY at 25 degrees C. Gas-phase products of the reaction of DMMP and oxygen in nanocrystalline NaY at 200 degrees C were monitored by FTIR spectroscopy and determined to be carbon dioxide (major product), formaldehyde, and dimethyl ether. In the presence of water, the thermal reaction of DMMP in nanocrystalline NaY at 200 degrees C yielded methanol (major product), carbon dioxide, and dimethyl ether. When the thermal reaction of DMMP in nanocrystalline NaY at 200 degrees C was conducted in the presence of water and oxygen, the predominant products were methanol and carbon dioxide. Hydroxyl sites located on the external zeolite surface were consumed during the DMMP thermal reactions as monitored by FTIR spectroscopy and were therefore determined to be the active sites in this reaction. 31P solid-state MAS NMR experiments were used to identify the surface-bound phosphorus complexes. The reactivity per gram of zeolite was comparable to other recently studied metal oxides such as MgO, Al2O3, and TiO2, and was found to have comparable, if not higher reactivity. Future improvements in reactivity may be achieved by incorporating a reactive transition metal ion or metal oxide nanocluster into the nanocrystalline NaY to enhance reaction rates and to achieve complete reaction of DMMP.

Specimens of {0 0 1} MgO, prepared for analysis in the transmission electron microscope (TEM), have been heated in situ in a conventional TEM in order to study the effect of different heat treatments on the surface of the MgO specimens. A previous study, using a similar in situ heat treatment of MgO, found that at elevated temperatures (∼500 K) a film of different structure and composition formed on the surface of the sample. The previous study concluded that the composition and structure corresponded to that of MgO 2 . In the present study, similar results to those shown previously have been found. However, the interpretation of these results is quite different. The films are shown to be of a composition and crystal structure that is consistent with forsterite, Mg 2 SiO 4 . The films can form as a result of contamination during the high-temperature in situ annealing process.

Thin films of MgFe2O4 spinel on a (001) substrate of MgO have been heated to elevated temperatures in an applied electric field. The externally applied electric field produces a large driving force that influences the kinetic behavior of the spinel film and results in the formation of an MgO layer at the cathode due to the higher mobility of the Mg2+ cations in the spinel. Through the use of both scanning and transmission electron microscopy, the evolution of this layer was followed through a series of heat treatments. Analysis of the decomposition process shows that initially isolated pockets of MgO form at the cathode surface. These pockets grow and eventually coalesce to form a continuous MgO layer. The two MgO/spinel heterojunctions behave differently since one is morphologically stable while the other is morphologically unstable. TEM analysis showed that during the decomposition process, dislocation loops are formed in the vicinity of the MgO pockets. It is proposed that these dislocation loops form to accommodate the lattice misfit at the interface between the precipitating MgO and spinel.

Vector space models (VSMs) are mathematically well-defined frameworks that have been widely used in text processing. In these models, high-dimensional, often sparse vectors represent text units. In an application, the similarity of vectors -- and hence the text units that they represent -- is computed by a distance formula. The high dimensionality of vectors, however, is a barrier to the performance of methods that employ VSMs. Consequently, a dimensionality reduction technique is employed to alleviate this problem. This paper introduces a new method, called Random Manhattan Indexing (RMI), for the construction of L1 normed VSMs at reduced dimensionality. RMI combines the construction of a VSM and dimension reduction into an incremental, and thus scalable, procedure. In order to attain its goal, RMI employs the sparse Cauchy random projections.

Electrically-injected vertical external cavity surface emitting laser (VECSEL) arrays are an attractive source for lowcost, high-brightness applications. Optical pumping can be used to investigate the emission properties of such devices without undergoing complex device fabrication. The design of such arrays is based on a single VECSEL chip, a 2D lens array, and a flat output coupling dichroic mirror. In this work, we report on the demonstration of an optically pumped, coherently-coupled VECSEL array. The array achieves a maximum total output power of >60 mW and lasing spectrum indicates single-mode operation. Near-field characterization reveals 37 individual lasing elements in a hexagonal array. Far-field measurements show an interference pattern which is consistent with inphase coherent coupling, with >60% of the total output power present in the on-axis central lobe. The physical origin of coherent coupling is attributed to diffractive coupling. The simplicity of the optical cavity design suggests scalability to much larger arrays, making the result of particular interest to the development of low-cost, highbrightness diode sources.

We demonstrate 2-dimentional coherently coupled bottom-emitting VCSEL arrays. In-phase operation has been obtained from 3-element triangular arrays, while out-of-phase operation has been obtained from 2x2, 3x3, and 4x4 arrays.

A number of the compounds proposed as replacements for substances controlled under the Montreal Protocol have extremely short atmospheric lifetimes, on the order of days to a few months. An important example is n-propyl bromide (also referred to as 1-bromopropane, CH2BrCH2CH3 or simplified as 1-C3H7Br or nPB). This compound, useful as a solvent, has an atmospheric lifetime of less than 20 days due to its reaction with hydroxyl. Because nPB contains bromine, any amount reaching the stratosphere has the potential to affect concentrations of stratospheric ozone. The definition of Ozone Depletion Potentials (ODP) needs to be modified for such short-lived compounds to account for the location and timing of emissions. It is not adequate to treat these chemicals as if they were uniformly emitted at all latitudes and longitudes as normally done for longer-lived gases. Thus, for short-lived compounds, policymakers will need a table of ODP values instead of the single value generally provided in past studies. This study uses the MOZART2 three-dimensional chemical-transport model in combination with studies with our less computationally expensive two-dimensional model to examine potential effects of nPB on stratospheric ozone. Multiple facets of this study examine key questions regarding the amount of bromine reaching the stratosphere following emission of nPB. Our most significant findings from this study for the purposes of short-lived replacement compound ozone effects are summarized as follows. The degradation of nPB produces a significant quantity of bromoacetone which increases the amount of bromine transported to the stratosphere due to nPB. However, much of that effect is not due to bromoacetone itself, but instead to inorganic bromine which is produced from tropospheric oxidation of nPB, bromoacetone, and other degradation products and is transported above the dry and wet deposition processes of the model. The MOZART2 nPB results indicate a minimal correction of the two-dimensional results in order to derive our final results: an nPB chemical lifetime of 19 days and an Ozone Depletion Potential range of 0.033 to 0.040 for assumed global emissions over landmasses, 19 days and 0.021 to 0.028, respectively, for assumed emissions in the industrialized regions of the Northern Hemisphere, and 9 days and 0.087 to 0.105, respectively, for assumed emission in tropical Southeast Asia.

Epitactic thin films of nickel ferrite spinel (NiFe 2 O 4 ) have been grown on (0 0 0 1) oriented sapphire substrates using pulsed-laser deposition. Three different methods were used to produce the films. The first was direct deposition using a stoichiometric NiFe 2 O 4 target. In the other two methods, a solid-state reaction between NiO and Fe 2 O 3 was utilized to produce the spinel. In one case, the spinel was formed in situ while film growth occurred in the deposition system; in the other case, a NiO/Fe 2 O 3 heterostructure was reacted ex situ at elevated temperatures in air. The resulting ferrite films were analyzed in cross section using both conventional and high-resolution transmission electron microscopy. In general, the predominant defects found in the spinel films were twin boundaries. However, the topology of the twin boundaries in each of the three films was different. These differences were attributed to, and correlated with, the growth method and reaction processes used to produce the spinel film.

The effectiveness of Pt in marking the initial location of heterophase boundaries between two reactants in a thin-film solid-state reaction is discussed. The Pt markers were produced by dewetting a continuous Pt film at elevated temperatures, thus forming an array of small isolated particles. These particles can then serve as fine-scale markers for tracking the motion of interfaces. The thin-film diffusion couples with Pt markers were used, in this study, to investigate the effect of an applied electric field on a spinel-forming reaction. The reacted diffusion couples with Pt markers were analysed using both transmission and scanning electron microscopy. Analysis of the diffusion couples showed that the Pt markers could be affected by, or themselves affect, the reaction process. The interface between the Pt marker and surrounding oxide matrix plays an important role in the reliability of Pt as an effective marker.

The use of Pt to mark the initial location of heterophase boundaries in solid-state reactions was extended to investigate the motion of interfaces during a thin-film solid-state reaction between In2O3 and MgO in the presence of an electric field. The Pt markers were prepared by sputtering a thin Pt film onto a single-crystal substrate. The resulting multilayer was then heated prior to thin-film deposition to de-wet the Pt film and thus form an array of small, isolated particles. These particles serve as fine-scale markers for tracking the motion of interfaces. However, there are certain situations in which the markers can move with the interface.

The effect of an external electric field applied, at elevated temperatures, to a thin-film diffusion couple has been studied. Thin films of epitactic Fe-oxide were deposited on {001} MgO by means of pulsed-laser deposition. The diffusion couple was then reacted at 1150 °C in air for 2 h in an applied field of 5 kV cm −1 . The distribution of phases after the reaction was determined using backscatter low-voltage scanning electron microscopy. In performing the analysis, images taken from the field-applied diffusion couple were compared to those of a standard diffusion couple of the same geometry with no applied field. The results showed that the application of an electric field affects both the diffusion of the cations and the interface morphology.

Solid-state reactions are known to occur in composite materials during fabrication, processing or service. In the present study, a model approach for studying such reactions is illustrated. The goal of this approach is to understand the effects of, for example, temperature, time and other driving forces on the earliest stages of such reactions. Three different materials systems were used in order to investigate some of the fundamental processes occurring. Two of the systems involve spinel formation while the other is more complicated, since three different compounds can form between the end-members. For all of these systems a thin-film reaction geometry was utilized. High-quality thin films of the various oxides were deposited on bulk substrates by pulsed-laser deposition. NiO was deposited on four orientations of α-Al2O3 in order to study the effect of crystal orientation (and therefore interfacial structure) on the growth kinetics of the nickel–aluminate spinel. The effect of an external electric field at elevated temperatures on the spinel-forming reaction between Fe oxide and monocrystalline (001) MgO has been analysed. Thin films of Y2O3 were reacted with monocrystalline substrates of α-Al2O3 at elevated temperatures to determine the reaction sequence: up to three different yttrium aluminates can form.

The work has demonstrated both top and bottom emitting coherently coupled VCSEL arrays operating in the preferred in-phase supermode. Moreover, it was shown that phase tuning between the array elements is possible with varying injection current to the array elements. With the bottom emitting arrays, these would be able to scale up the array size, maximum power, and beam steering properties.

We demonstrate the first clearly in-phase emission and first continuous-wave operation from a bottom-emitting, coherent VCSEL array. A 2×1 array with an antiguided index profile was used, representing a critical step towards coherent, high-brightness arrays.

The determination of orientation relationships between thin oxide films and the underlying single-crystal oxide substrates using electron backscattered diffraction (EBSD) in scanning electron microscopy (SEM) is discussed. In these well-defined systems, complementary information concerning the local chemistry can be obtained using high-resolution backscattered electron (BSE) imaging. Recent studies have shown the value of using EBSD patterns (EBSPs) in SEM.

Two potential applications of coherently coupled vertical cavity surface emitting laser (VCSEL) phased arrays include beam-steering [1,2] and high-brightness sources [3]. While a major difficulty for high brightness VCSEL arrays has been that typical evanescent coupling designs lead to the undesired out-of-phase supermode [4], we have shown reliable in-phase operation using ion-implantation and photonic crystal confinement, which requires a relatively simple fabrication process [5]. Common to both beam-steering and high power applications is the need to carefully control the phase difference between neighboring elements of the optically coupled array. We report measurement of the relative phase in coherently-coupled in-phase VCSEL arrays and show that the phase can be varied by differential current injection over a full range of π, requiring < 200 μA, which is several orders of magnitude lower than phase tuning by similar methods in slab-coupled lasers [6].

Electronically steerable laser sources have applications in areas such as optical display, free space communications, and illumination. Among the multiple figures of merit for beam steering, speed is still a limiting factor for many applications including laser radar [1]. While mechanical methods clearly have inertial limitations, even the fastest available liquid crystal optical phased array techniques are limited to speeds under 10 kHz [2, 3]. We show that electronic beam steering using phased vertical cavity surface emitting laser (VCSEL) arrays [4–6] can be steered as fast as 100 MHz while possessing the inherent advantages of system robustness, radiation hardness, and energy efficiency.