Fabrication and electrical characteristics of high-performance ZnO nanorod field-effect transistors

We report on fabrication and electrical characteristics of high-mobility field-effect transistors (FETs) using ZnO nanorods. For FET fabrications, single-crystal ZnO nanorods were prepared using catalyst-free metalorganic vapor phase epitaxy. Although typical ZnO nanorod FETs exhibited good electrical characteristics, with a transconductance of similar to140 nS and a mobility of 75 cm(2)/V s, the device characteristics were significantly improved by coating a polyimide thin layer on the nanorod surface, exhibiting a large turn-ON/OFF ratio of 10(4)-10(5), a high transconductance of 1.9 muS, and high electron mobility above 1000 cm(2)/V s. The role of the polymer coating in the enhancement of the devices is also discussed. (C) 2004 American Institute of Physics.X11333sciescopu

Source of tubercle bacilli in cervical lymph nodes: A prospective study

A prospective study searching for associated mycobacterial infection of the upper aerodigestive tract in patients with cervical tuberculous lymphadenitis (TBLN) was carried out. One hundred and thirteen patients with a clinical suspicion of cervical TBLN were included. All patients had a physical examination of the upper aerodigestive tract. Routine endoscopy and biopsy of the nasopharynx were performed. All of them had surgery to the cervical lymph node. Seventy-five patients had histologically confirmed cervical TBLN. Culture of the lymph node specimen showed Mycobacterium tuberculosis in 68 (90 per cent). In 45 (60 per cent) patients with cervical TBLN the primary foci of infection could not be found. Twenty-nine (39 per cent) had radiographic evidence of active or healed pulmonary tuberculosis. Sputum culture from two patients showed Mycobacterium tuberculosis. Five patients (six per cent) had tuberculous nasopharyngitis. In one of them (one per cent) the tuberculous nasopharyngitis was primary as no other evidence of mycobacterial infection was found. In the present study, mycobacterial infection of other parts of the upper aerodigestive tract was not found.published_or_final_versio

Average-Case Optimal Approximate Circular String Matching

Approximate string matching is the problem of finding all factors of a text t of length n that are at a distance at most k from a pattern x of length m. Approximate circular string matching is the problem of finding all factors of t that are at a distance at most k from x or from any of its rotations. In this article, we present a new algorithm for approximate circular string matching under the edit distance model with optimal average-case search time O(n(k + log m)/m). Optimal average-case search time can also be achieved by the algorithms for multiple approximate string matching (Fredriksson and Navarro, 2004) using x and its rotations as the set of multiple patterns. Here we reduce the preprocessing time and space requirements compared to that approach

Tud-1 supported vanadium-doped titania photocatalyst

New photocatalyst of Techniche Universiteit Delft-1 (TUD-1) supported 5 mol% V doped TiO2 (5V-TiO2 /TUD-1) exhibited enhanced activity in methylene blue photodegradation. XRD results revealed the presence of both anatase and rutile phases in the V-doped TiO2 sample. After loading onto TUD-1, the crystallinity of the sample dropped significantly, implying well dispersion of both V and TiO2 on the TUD-1. DRUV-Vis results suggested alteration of Ti species in the presence of TUD-1. Besides, the band gap energy of V-doped TiO2 decreased after loading onto TUD-1. The sample 5V-TiO2 /TUD-1 possessed high surface area of 626 m2 /g. The photocatalytic performance of the sample was evaluated through the photodegradation of methylene blue under UV irradiation. It has been demonstrated that 5V-TiO2 /TUD-1 was a better photocatalyst compared to TUD-1 and unsupported V-doped TiO2 . The current findings strongly indicated that TUD-1 played an important role as support to improve the photocatalytic activity of V-doped TiO2

Stridor in Asian infants: assessment and treatment

Stridor is the main symptomof upper airway obstruction in infants. It can be congenital or acquired, acute or chronic. Pathologies can be located from the nose down to the trachea. Common causes include laryngomalacia, vocal cord palsy, subglottic stenosis, tracheal anomaly, laryngeal cleft, vascular and lymphatic malformation, laryngeal papillomas, craniofacial abnormalities and even head and neck tumours. In this paper, we will discuss our approach to infants with stridor including assessment with flexible and rigid endoscopy and treatments to various conditions in a tertiary centre. Causes of stridor in infants undergoing rigid laryngotracheobronchoscopy in Queen Mary Hospital, University of Hong Kong Medical Centre between 2005 and 2011 will be retrospectively reviewed. Treatments according to various conditions will be discussed. Successful management of these neonates requires accurate diagnosis, early intervention, and multidisciplinary care by ENT surgeons, paediatricians, and paediatric anaesthetists.published_or_final_versio

Effect of using micropalm oil fuel ash as partial replacement of cement on the properties of cement mortar

This study investigates the effects of micropalm oil fuel ash (mPOFA) on compressive strength and pore structure of cement mortar. Various experimental techniques, such as compression test, isothermal calorimetry, mercury intrusion porosimetry, and X-ray diffraction, are performed to figure out the effect of using mPOFA as partial replacement of cement on the hydration of cement and determine its optimal replacement level to increase mechanical property of the mortar specimens. 10 wt.% of cement replacement with mPOFA is found to give the highest level of compressive strength, achieving a 23% increase over the control specimens after 3 days of curing. High K2O contents in mPOFA stimulate C3S in cement to form C-S-H at early ages, and high surface area of mPOFA acts as a nucleus to develop C-S-H. Also, small mPOFA particles and C-S-H formed by pozzolanic reaction fill the pores and lead to reduction in large capillary pores. In XRD analysis, a decrease in Ca(OH)2 and SiO2 contents with age confirmed a high pozzolanic reactivity of mPOFA

Effects of Treated Manure Conditions on Ammonia and Hydrogen Sulfide Emissions from a Swine Finishing Barn Equipped with Semicontinuous Pit Recharge System in Summer

Gaseous emissions from animal production systems affect the local and regional air quality. Proven farm-scale mitigation technologies are needed to lower these emissions and to provide management practices that are feasible and sustainable. In this research, we evaluate the performance of a unique approach that simultaneously mitigates emissions and improves air quality inside a barn equipped with a manure pit recharge system. Specifically, we tested the effects of summertime feeding rations (used by farmers to cope with animal heat stress) and manure management. To date, the pit recharge system has been proven to be effective in mitigating both ammonia (NH3; approximately 53%) and hydrogen sulfide (H2S; approximately 84%) emissions during mild climate conditions. However, its performance during the hot season with a high crude protein diet and high nitrogen loading into the pit manure recharge system is unknown. Therefore, we compared the emissions and indoor air quality of the rooms (240 pigs, ~80 kg each) equipped with a conventional slurry and pit recharge system. The main findings highlight the importance and impact of seasonal variation and diet and manure management practices. We observed 31% greater NH3 emissions from the pit recharge system (33.7 ± 1.4 g·head−1·day−1) compared with a conventional slurry system (25.9 ± 2.4 g·head−1·day−1). Additionally, the NH3 concentration inside the barn was higher (by 24%) in the pit recharge system compared with the control. On the other hand, H2S emissions were 55% lower in the pit recharge system (628 ± 47 mg·head−1·day−1) compared with a conventional slurry pit (1400 ± 132 mg·head−1·day−1). Additionally, the H2S concentration inside the barn was lower (by 54%) in the pit recharge system compared with the control. The characteristics of the pit recharge liquid (i.e., aerobically treated manure), such as the total nitrogen (TN) and ammonium N (NH4-N) contents, contributed to the higher NH3 emissions from the pit recharge system in summer. However, their influence on H2S emissions had a relatively low impact, i.e., emissions were still reduced, similarly as they were in mild climate conditions. Overall, it is necessary to consider a seasonal diet and manure management practices when evaluating emissions and indoor air quality. Further research on minimizing the seasonal nitrogen loading and optimizing pit recharge manure characteristics is warranted