The knowledge of pre‐exponential factors and activation energies for low temperatures and short annealing times in nanoscaled systems is important for the downscaling of thermal processes. Here, the diffusion coefficients in aluminum–nickel, aluminum–titanium, titanium–silicon, and aluminum–copper bilayers were determined using rapid thermal annealing. The annealing time was set to 500 s and the investigated bilayer thin film thicknesses were 2 µm. The temperatures ranged from 389 to 613 K depending on the bilayer system. For the various material combinations, the diffusion coefficients were determined by elemental depth profiling and compared to literature values. For the aluminum–copper system, a good agreement with literature and a single set of values was found, whereas for aluminum–nickel, aluminum–titanium, and titanium–silicon two or more sets of values were observed.

The need for interoperation and data exchange through the Internet has made Extensible Markup Language (XML) a dominant standard language. Much work has already been done on translating relational data into XML documents and vice versa. However, there is not an integrated method to combine them together as a unifying technology for database interoperability on the Internet. Users may not be familiar with various query language syntax. We propose database gateways built on the top of a Relational Database (RDB) and an XML Database (XMLDB). Users can access both databases at the same time through the query language SQL or XQL (an XML query language) to access data stored in either RDB or XMLDB. The translation process adopts query graph translation between a RDB and an XMLDB. Thus, a stepwise procedure of query translation is devised and amenable to implementation. The procedure also provides an XML interface to a RDB as well as a relational interface to XMLDB. A location counter sequence number is used to position tuples in a RDB for subsequent transforming the tuples into the corresponding positioning element instances in the XML documents. As a result, both XMLDB and RDB can co-exist, and be accessible by the users.

Numerical simulation was carried out to determine the dynamic properties of the Tsing Ma Suspension Bridge. Both the structure as a whole and individual subcomponents were modeled. Classical analytical solutions for simplified models from the available literature were compared with the results obtained from a finite-element code. Quantitative results for static deflection, natural frequencies, and mode shapes were compared with analytical solutions from linear theory. Out-of-plane modes were shown to be dominant. For in-plane antisymmetric and symmetric bending modes, in which the suspension cable and bridge deck vibrate in the same direction, the natural frequency of the main span of the bridge is determined to be approximately equal to the square root of the sum of the squares of the frequencies of the cable and bridge deck.

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Background Thyroiditis and Graves’ disease have been reported after COVID-19 vaccination. Patients with hypothyroidism due to various etiologies may be at risk of thyroid-specific outcomes. We aimed to evaluate the risks of thyroid-specific outcomes and adverse events after COVID-19 vaccination among patients treated for hypothyroidism. Methods In this population-based cohort from Hong Kong Hospital Authority electronic health records with Department of Health vaccination records linkage, levothyroxine users were categorized into unvaccinated, vaccinated with BNT162b2 (mRNA vaccine) or CoronaVac (inactivated vaccine) between 23 February and 9 September 2021. Propensity score (PS) weighting with inverse probability of treatment weighting (IPTW) was applied to balance the baseline characteristics among the three groups, which included age, sex, history of COVID-19, health care utilization, comorbidities, baseline thyroid-stimulating hormone (TSH) level (within the 6 months before the index date), and recent use of medications including anti-hypertensive, anti-diabetic and lipid-lowering agents. Study outcomes were dosage reduction or escalation in levothyroxine, emergency department visit, unscheduled hospitalization, adverse events of special interest (AESI) according to World Health Organization's Global Advisory Committee on Vaccine Safety, and all-cause mortality. Results In total, 47,086 levothyroxine users were identified (BNT162b2: n=12,310; CoronaVac: n=11,353; unvaccinated: n=23,423). After PS weighting, all baseline characteristics had standardised differences of less than 0.2, implying a balance of covariates among the three groups. COVID-19 vaccination was not associated with increased risks of levothyroxine dosage reduction (BNT162b2: HR=0.971, 95% CI 0.892–1. 058; CoronaVac: HR=0.968, 95% CI 0.904–1. 037) or escalation (BNT162b2: HR=0.779, 95% CI 0.519–1.169; CoronaVac: HR=0.715, 95% CI 0.481–1. 062). Besides, COVID-19 vaccination was not associated with a higher risk of emergency department visits (BNT162b2: HR=0.944, 95% CI 0.700-1.273; CoronaVac: HR=0.851, 95% CI 0.647-1.120) or unscheduled hospitalization (BNT162b2: HR=0.905, 95% CI 0.539-1.520; CoronaVac: HR=0.735, 95% CI 0.448-1.207). There were two (0. 016%) deaths and six (0. 062%) AESI recorded for BNT162b2 recipients, and one (0. 009%) and three (0. 035%) for CoronaVac recipients, respectively. Sensitivity analyses were performed by stratifying the groups according to age, sex and pre-vaccination thyroid status. The results were largely consistent with the main analysis. Conclusion BNT162b2 or CoronaVac vaccination is not associated with unstable thyroid status or an increased risk of adverse outcomes among patients treated for hypothyroidism. These reassuring data should encourage them to get vaccinated against COVID-19 for protection from potentially worse COVID-19-related outcomes. Presentation: No date and time listed