Research and development of magnesium/aluminum electroforming process for solar concentrators Final report, 13 May 1966 - 10 May 1967

Magnesium and aluminum electroforming process for solar concentrator

Probing ultrafast carrier dynamics and nonlinear absorption and refraction in core-shell silicon nanowires

We investigate the relaxation dynamics of photogenerated carriers in silicon nanowires consisting of a crystalline core and a surrounding amorphous shell, using femtosecond time-resolved differential reflectivity and transmission spectroscopy at photon energies of 3.15 eV and 1.57 eV. The complex behavior of the differential transmission and reflectivity transients is the mixed contributions from the crystalline core and the amorphous silicon on the nanowire surface and the substrate where competing effects of state filling and photoinduced absorption govern the carrier dynamics. Faster relaxation rates are observed on increasing the photo-generated carrier density. Independent experimental results on crystalline silicon-on-sapphire help us in separating the contributions from the carrier dynamics in crystalline core and the amorphous regions in the nanowire samples. Further, single beam z-scan nonlinear transmission experiments at 1.57 eV in both open and close aperture configurations yield two-photon absorption coefficient \$beta$ (~3 cm/GW) and nonlinear refraction coefficient \$gamma$ (-2.5x10^-4 cm2/GW).Comment: 6 pages, 6 figure

Commission des Communautes Europeennes: Groupe du Porte-Parole = Commission of European Communities: Spokesman Group. Spokesman Service Note to National Offices Bio No. (81) 276, 8 July 1981

This paper presents a novel approach for multi-lingual sentiment classification in short texts. This is a challenging task as the amount of training data in languages other than English is very limited. Previously proposed multi-lingual approaches typically require to establish a correspondence to English for which powerful classifiers are already available. In contrast, our method does not require such supervision. We leverage large amounts of weakly-supervised data in various languages to train a multi-layer convolutional network and demonstrate the importance of using pre-training of such networks. We thoroughly evaluate our approach on various multi-lingual datasets, including the recent SemEval-2016 sentiment prediction benchmark (Task 4), where we achieved state-of-the-art performance. We also compare the performance of our model trained individually for each language to a variant trained for all languages at once. We show that the latter model reaches slightly worse – but still acceptable – performance when compared to the single language model, while benefiting from better generalization properties across languages

Design of a ferrite rod antenna for harvesting energy from medium wave broadcast signals

Radio frequency (RF) energy harvesting is an emerging technology that has the potential to eliminate the need for batteries and reduce maintenance costs of sensing applications. The antenna is one of the critical components that determines its performance and while antenna design has been well researched for the purpose of communication, the design for RF energy harvesting applications has not been widely addressed. The authors present an optimised design for such an antenna for harvesting energy from medium wave broadcast transmissions. They derive and use a model for computing the optimal antenna configuration given application requirements on output voltage and power, material costs and physical dimensions. Design requirements for powering autonomous smart meters have been considered. The proposed approach was used to obtain the antenna configuration that is able to deliver 1 mW of power to 1 kΩ load at a distance of up to 9 km, sufficient to replace batteries on low-power sensing applications. Measurements using a prototype device have been used to verify the authors simulations

The challenge of differentiating vaso-occlusive crises from osteomyelitis in children with sickle cell disease and bone pain: A 15-year retrospective review

Purpose The paediatric sickle cell disease (SCD) osteomyelitis (OM) incidence is 0.3% to 12%. Differentiating vaso-occlusive crises (VOC) from OM is a diagnostic challenge, with limited evidence guiding management. We present a 15-year review of a paediatric sickle cell cohort. We aim to identify OM incidence and provide a management protocol for these children presenting with bone pain. Methods A prospective database of children with haemoglobinopathies (2002 to 2017) was analyzed for temperature, C-reactive protein (CRP) and white cell count (WCC) on admission as well as imaging, treatment and cultures. OM diagnosis was supported by imaging and blood cultures. VOC was defined as bone pain that improved without antibiotics. Results Over 15 years, 96 children with SCD presented 358 times to hospital. Empirical antibiotics were given in 308 presentations. There were five cases of OM (1.4%); two acute and three chronic. In all, 50 presentations of VOC were identified. No significant differences in age were noted between the OM and VOC group. Temperature and CRP were significantly elevated in the OM group with no significant difference in WCC. Cultures were only positive in the chronic OM admissions. There were no cases of septic arthritis. No surgical intervention was required. Conclusion In children with SCD presenting with persistent bone pain, fever, elevated CRP and WCC, OM should be suspected and prompt antibiotic treatment started. Our treatment pathway was successful avoiding OM in 98.6% and septic arthritis in 100%. Further research on novel biological markers distinguishing OM from VOC should be investigated. Level of Evidence II

Properties and Device Applications of Hydrogenated Amorphous Silicon Carbide Films

Hydrogenated amorphous silicon carbide (a‐SiC:H) films were deposited with a radio‐frequency plasma‐enhanced chemical vapor deposition system which utilizes a dc electric field applied independently of the inductively coupled rf field. The source gases were SiH4 and CH4. It was found that application of an electric field directed out of the substrate surface enhances the growth rate and yields some improvements in photoconductivity. The compositions of the films were evaluated by x‐ray photoelectron spectroscopy for a range of source gas mixtures. In order to assess the applicability of a‐SiC:H thin films, heterojunction a‐SiC:H/crystalline Si (c‐Si) diodes were fabricated and their electrical characteristics evaluated. The diode capacitance‐voltage results confirmed a step junction, which was consistent with the abruptness of the interface demonstrated by high‐resolution transmission electron microscopy. The heterojunction diodes also showed good rectifying properties, suggesting promise for a‐SiC: H in device applications

Airway smooth muscle pathology in Pompe Disease

Pompe disease is a rare autosomal recessive disease which results from a deficiency of acid α-glucosidase (GAA) - an enzyme that degrades lysosomal glycogen. Patients with Pompe disease develop intra-lysosomal accumulation of glycogen in multiple tissues including skeletal muscle, CNS and smooth muscle. Pulmonary dysfunction is a hallmark of Pompe disease and has classically been attributed to muscle weakness and CNS neuropathology. However, the potential role of respiratory smooth muscles in the respiratory pathology is unknown. Therefore we postulated that GAA deficiency results in airway smooth muscle glycogen accumulation that leads to airway smooth muscle dysfunction. Using the Pompe mouse model, the Gaa-/- mouse, we examined the airway smooth muscle structure and function. We used in vivo forced oscillometry measurements (N=7WT, N=7 Gaa-/-) to examine pulmonary physiology and administered methacholine challenges to assess in vivo airway resistance. Also, we used ex-vivo contraction testing (N=6WT, N=5 Gaa-/-) to determine bronchi contractility. In response to the highest dose methacholine challenge (100mg/ml), there was a significant decrease in conducting airway resistance in Gaa-/- versus WT mice (p=0.007). Also, ex vivo bronchi contraction testing demonstrated a significantly weaker response to potassium chloride (p=0.008) and methacholine (2-way ANOVA p=0.005) in Pompe mice compared to WT mice, suggesting impaired smooth muscle contraction. Furtherly, we performed PAS staining on fresh-frozen tissue to examine the degree of glycogen accumulation as a result of GAA deficiency. PAS staining revealed robust glycogen accumulation in the trachea and bronchi of Pompe mice and a disruption of the airway smooth muscle architecture. In conclusion, GAA deficiency results in glycogen accumulation and a disruption of the architecture in the airway smooth muscles of Gaa-/- mice. Furthermore, both in vivo and ex vivo tests reveal that Gaa-/- murine airways have impaired function as evidenced by decreased contractility and a decreased response to methacholine

The Role of Artificial Intelligence for Business Value

An increasing number of organizations are investing in Artificial intelligence (AI), but not all AI implementation leads to improved performance. To contribute to organizational business value, two components of AI resources, AI assets and AI capabilities, should be complementary in the business value creation process. In this study, based on IT business value literature and through the lens of dynamic capabilities, the role of AI resources in organizational value creation is explored. It is proposed that AI resources would enable organizations to develop process-oriented dynamic capabilities (PDCs), contributing to business value. This study will examine how organizations build AI capabilities and the roles of AI resources in creating business values through case studies. This research will offer a framework that guides and assists practitioners in utilising AI resources and building AI capabilities. A deeper understanding of the subject through this study also enriches the growing body of literature on AI

The Static and Dynamic Lattice Changes Induced by Hydrogen Adsorption on NiAl(110)

Static and dynamic changes induced by adsorption of atomic hydrogen on the NiAl(110) lattice at 130 K have been examined as a function of adsorbate coverage. Adsorbed hydrogen exists in three distinct phases. At low coverages the hydrogen is itinerant because of quantum tunneling between sites and exhibits no observable vibrational modes. Between 0.4 ML and 0.6 ML, substrate mediated interactions produce an ordered superstructure with c(2x2) symmetry, and at higher coverages, hydrogen exists as a disordered lattice gas. This picture of how hydrogen interacts with NiAl(110) is developed from our data and compared to current theoretical predictions.Comment: 36 pages, including 12 figures, 2 tables and 58 reference