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Amid the search for efficient terahertz transmission and gas sensing, all‐polymer terahertz waveguides attract significant interest due to their compactness and capability for providing environmentally robust systems. The high loss within metals and dielectrics in the terahertz range makes it challenging to build a low loss, mechanically stable, and broadband terahertz waveguides. In this context, hollow waveguides made of Zeonex are promising for attaining low transmission loss in the terahertz range. Herein, a microstructured hollow hexagonal‐core fiber (HCF) is investigated, which exhibits low loss, near‐zero dispersion, wide operating bandwidth, and is suitable as a gas sensor. Notably, HCF fabrication is carried out by exploiting an efficient single‐step extrusion method—by a standard filament extruder and a puller; hence the production cost is low compared with conventional extrusion methods. This introduces a novel way of fabricating complex and low‐loss terahertz fibers. The experiments demonstrate that an HCF can achieve remarkably low attenuation and near‐zero flattened dispersion as compared with any other terahertz fibers. The resulting HCFs are easy to handle and have high thermal and chemical stability. These results bring significant advancements for terahertz fiber fabrication, low‐loss ultrafast short‐distance terahertz transmission, and sensing in the terahertz spectral domain.

To evaluate a newly developed noninvasive ambulatory, quantitative polymerase chain reaction (Q-PCR) Epstein-Barr virus (EBV) DNA detection and screening system (NP Screen™) for nasopharyngeal carcinoma (NPC).Correlation of the nasopharyngeal epithelial EBV-DNA levels and clinical findings by nasopharyngoscopy and final pathologic diagnosis of NPC with biopsy.Multicenter ENT/Oncology clinics in Hong Kong (Radiation Oncology Clinic at the Queen Elizabeth Hospital and Radiation Oncology Clinic and Head and Neck Clinic, Queen Mary Hospital, University of Hong Kong) and in Toronto, Canada (the Otolaryngology-Head and Neck Clinic at the Rouge Valley Health System and 2 large ENT practices in Toronto).A single-use trans-oral brush was used for rapid, nontraumatic nasopharyngeal (NP) epithelial cells DNA harvest in 600 Chinese patients, combined with a preservation and shipping kit for remote, real-time Q-PCR EBV DNA determinations.All 600 patients had NP brushings using NP Screen in an ambulatory environment, and no adverse events or complications were recorded. A final 578 patients were included with sufficient amount of DNA for completion of the Q-PCR assay. Of these 578 patients, 94 were confirmed positive for NPC histologically. The study yielded a sensitivity of 98.9%, specificity of 99.3%, positive predictive value (PPV) of 96.9%, and negative predictive value (NPP) of 99.7% for NP Screen in detecting NPC. Endoscopy had a sensitivity of 94%, specificity 97.1%, PPV 85%, and NPP 98.9%.The trans-oral brushing system fulfills the characteristics of a noninvasive, sensitive, specific detection method suitable for routine, large-scale ambulatory NPC risk assessment for high-risk NPC populations.

Objectives:Obstructive sleep apnea (OSA) is a common sleep disorder due primarily to upper airway obstruction. Certain ethnic groups, particularly Chinese, are more susceptible to a severe degree of OSA irrespective of body weight due in part to inherent narrow upper airway anatomy. In this study, we investigated the treatment outcome of combined upper airway surgeries: septoplasty (SP), turbinate reduction (TR), tonsillectomy, and uvulopalatoplasty (UVPP) on OSA in this ethnic group who have clinical identifiable upper airway anatomical obstruction and are unable to tolerate continuous positive airway pressure (CPAP) treatment.Methods:A retrospective study to analyze the effect of either: (1) SP and TR (inferior turbinectomy) only or (2) in combination with UVPP (partial uvulectomy and lateralization of palatal pillars) and standard tonsillectomy, on Chinese patients diagnosed with OSA. Outcome measures were obtained from pre- and postoperative polysomnographs (PSG) where sleep parameters, AHI, and oxyge...

The remaining life for a hypothetical pressure vessel containing a defect which is subject to thermal shock has been calculated. Twelve cases of thermal shock loads of different severity characterized by the dimensionless parameters, Biot (B) and Fourier (F) numbers, were analysed by finite element modelling (FEM). The estimation of remaining life for each case was carried out based on the PD6493 defect assessment procedure (1). The effect of thermal shock on the crack growth rate was quantified showing that more severe shocks accelerate crack growth while less severe shocks may lead to slow growth or eventual crack arrest.

Electric utility engineers have commented that extruded distribution cables frequently fail during or shortly after a thunder storm. These engineers also comment that failures often reoccur on cable circuits where previous failures were located with a thumper. Linemen at Georgia Power often make similar comments. To investigate this observation, crosslinked (XLPE) and tree retardant crosslinked (TRXLPE) power cable designs were subjected to accelerated water treeing tests. Samples were subjected to simulated lightning surges or simulated thumping surges. Crosslinked cables removed after 15 years of service operation were also subjected to these surges. The results show that, in some cases, lightning surges do reduce extruded distribution cable life. Also, high level thumping surges appear to reduce cable life once cables are well aged. >

Recently, there have been numerous food scares particularly with the production of milk powders for infants. This has been caused by the addition of excess melamine to increase the tested protein count of a powder. In this paper we investigate the potential of THz-TDS for use in food quality control and compare this technique to other established techniques. Refereed/Peer-reviewed

Objectives: To assess the association of diagnostic predictors available in the emergency department (ED) with the outcome diagnosis of severe acute respiratory syndrome (SARS). Methods: This retrospective cohort study describes all patients from the Amoy Garden complex who presented to an ED SARS screening clinic during a 2-month outbreak. Clinical and diagnostic predictors were recorded, along with ED diagnoses. Final diagnoses were established independently based on diagnostic tests performed after the ED visit. Associations of key predictors with the final diagnosis of SARS were described. Results: Of 821 patients, 205 had confirmed SARS, 35 undetermined SARS and 581 non-SARS. Multivariable logistic regression showed that the strongest predictors of SARS were abnormal chest x-ray (odds ratio [OR] = 17.4), subjective fever (OR = 9.7), temperature >38°C (OR = 6.4), myalgias (OR = 5.5), chills and rigors (OR = 4.0) and contact exposure (OR = 2.6). In a subset of 176 patients who had a complete blood cell count performed, the strongest predictors were temperature ≥38ºC (OR = 15.5), lymphocyte count Conclusions: Two components of the World Health Organization case definition — fever and contact exposure — are helpful for ED decision-making, but respiratory symptoms do not discriminate well between SARS and non-SARS. Emergency physicians should consider the presence of diarrhea, chest x-ray findings, the absolute lymphocyte count and the platelet count as significant modifiers of disease likelihood. Prospective validation of these findings in other clinical settings is desirable.

Tables of normal values are available for the measurement of four sagittal diameters (Roof, FM, C1 and C2) and areas of the soft tissue of the nasopharynx as seen in the lateral neck radiograph. The lateral neck radiographs of 100 nasopharyngeal carcinoma (NPC) cases as well as 100 normal controls of corresponding sex and age distribution are measured to ascertain the usefulness of the above measurement in the detection of NPC. Depending on the method of calculation, figures for positive results (sensitivity) may rise to as high as 85% but the specificity (i.e. probability of a correct diagnosis in a person without NPC) is at the same time lowered to 92%. The detection of NPC from any lateral neck radiograph, however, presents a different problem compared to the situation when a person clinically suspected of having NPC is referred for radiography. Many factors are involved in the former situation and it is to this situation that the predictive value (PV) of the scores has to be employed.

Laboratory tests were performed to investigate the effects of lightning and thumping impulses on the performance of various 15 kV cable designs. The cable designs were aged in the laboratory using an accelerated water treeing test. Some samples were subjected to lightning impulses, some were subjected to thumping impulses, and some were aged without impulses applied. The impulse effects were evaluated using time to failure data, AC breakdown data, and impulse breakdown data. The results show that lightning or thumping impulses do not affect cable AC or impulse breakdown strength. There is also no visual difference between wafers taken from impulsed and control samples. However, there is a strong indication that lightning impulses can reduce cable life. Almost all the aging failures occurred while the cables were warm. No failures occurred during the impulse application. It is also shown that increased cable wall thickness extends cable life for the tree-resistant high-molecular-weight insulation material tested, but not for the crosslinked polyethylene insulation material tested. >

The authors recommend measurement of four sagittal diameters of the soft tissue of the nasopharynx, namely, “Roof”, “FM”, “Cl” and “C2”. Values of these diameters are derived from a study of lateral neck radiographs of 640 Chinese in Singapore, and their means and standard deviations presented by age and sex. Significant age and sex differences of varying degrees are found in all parameters. Age and sex should therefore be taken into consideration when assessing individual observations. The value of the lateral neck radiograph in the detection of masses of the nasopharynx was recognized since the early 1930s. Thus, Groth (1931) described adenoid vegetations. Digby and Khoo (1934) stated that in nasopharyngeal carcinoma X rays could show up as an irregularity of the nasopharyngeal clear space. Ho (1961) suggested a method of measurement of the roof and upper posterior wall of nasopharynx. Oon (1964) supplied a table of normal diameters from a study of 150 adults of various races. Johannesson (1968...

A case of systemic lupus erythematosus is described in which for 10 years the only significant findings were erythema multiforme and vasculitis. Gross hepatosplenomegaly with persistent pancytopenia developed, and bone marrow examination revealed the presence of sideroblasts. The patient's condition deteriorated, and subsequently she developed a severe bleeding tendency, terminating in erythroleukaemia.

Underground power cables on electric utility systems are frequently subjected to lightning impulses during normal service. They can also be subjected to impulses from fault locating equipment (thumpers). The effects of these impulses on the power cable's life is not well defined. Various cable designs were aged in the laboratory using an accelerated water treeing test. Some samples were subjected to lightning impulses, some to thumping impulses and some were aged without impulses applied. The impulse effects were evaluated using time to failure data, ac breakdown data and impulse breakdown data. The results show that lightning or thumping impulses do not affect cable ac or impulse breakdown strength. There is also no visual difference between wafers taken from impulsed and control samples. However, there is a strong indication that lightning impulses can reduce cable life. Interestingly, almost all the aging failures occurred while the cable were warm. No failures occurred during the impulse application. Also, increased cable wall thickness extended cable life for one insulation but not for another. ..