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A novel polarization-insensitive metasurface with angular stability for ultra-broadband (from 7 to 12 GHz) backscatter radar cross section (RCS) reduction is investigated. The proposed metasurface is composed of carefully arranged unit cells with spatially varied dimension, which can diffuse reflection uniformly and avoid the reflection in the specular direction. A proposed metasurface sample is fabricated and tested to validate RCS reduction behavior predicted by full-wave simulation software ANSYS HFSS. A more than 10 dB RCS reduction within the entire X-band is observed, indicating our metasurface may be potentially applied to future stealth technology.

Volatile sulfur compounds are the main odorants at landfills. In this study, methanethiol (CH3SH) was chosen as a typical volatile organic sulfur compound, and its generation potential was investigated during the anaerobic degradation of the organic fractions of municipal solid waste (MSW) including rice, flour food, vegetable, fish and pork, paper, cellulose textile, and yard wastes. Among the experimental wastes, gas generation was the highest in the fish and pork waste with a high CH3SH concentration of up to 2.5% (v/v). Sulfur reduction in the solid phase was mostly converted into gaseous sulfur compounds. During the whole experiment, the cumulative CH3SH generation from the fish and pork waste was 0.139 L kgdw −1, which was about 2 and 6 orders of magnitude higher than that from the other experimental wastes. The ratio of CH3SH-S to TS reduction was 31.56% in the fish and pork waste. These results would be helpful to understand the generation of volatile sulfur compounds during the anaerobic degradation of MSW and develop techniques to control odor pollution at landfills.

During the Ming Dynasty, based on talent demand, Zhu Yuanzhang require schools to cultivate both civil and military personnel, at all levels of the school building fire garden, archery, and establish the evaluation standard. But due to "ride and shoot" sports content eventually did not enter the scope of the imperial examination, has not been able to officer students' attention, unsettled finally. In the Qing Dynasty, the rulers of the Qing Dynasty based on the social and political needs, riding and shooting education is one of the basic contents of the Eight Banners, riding and shooting will be closely integrated examinations, powerful promote the development of riding and shooting for the Eight Banners school.

This paper introduced one optimized proactive cooling management approach based on power variation trend analysis. Through analyzing the data center historical power telemetries, the power predictor is able to predicate power variation with 5– 15 minutes granularity. The cooling controller uses the observed heat information and estimated thermal variation trend to drive CRAC to manage temperature situation at prediction window. To validate cooling results from different cooling parameters, one risk level evaluation method is proposed and the experiments for different prediction window are conducted and the result is presented.

A novel polarization-independent Mu-negative metamaterial with broad bandwidth named fan-shaped structure, composed of periodically arranged capacity-loaded fan-shaped patches symmetrically printed on the both side of a FR4 substrate, is theoretically and numerically investigated in this paper. First, the effective constitutive parameters are retrieved from the computed scattering parameters and are found having a negative permeability characteristic in the frequency range of 6.86–9.46 GHz, which is much wider than conventional split-ring resonator. Second, simplified equivalent LC models based on detailed study of field and surface current distribution, which can account for the characteristics of its electromagnetic behaviour, are introduced. Expressions of magnetic and electric resonance frequencies, deduced from the LC models, are presented as well. Finally, the dependence of the negative permeability characteristic on the system’s geometrical parameters is analysed through a parametric investigation....

Bench test and computational fluid dynamics (CFD ) simulation of the air pump loss on the 380 hydraulic retarder are completed in this paper . It turns out that the CFD simulation has nice reliability from the contrast of the air pump loss between the test and the simulation . And on this foundation , CFD simulation of two kinds of retarders with different turbulent structures is done . The contrast of the results of the simulation give the effects of different turbulent structures on cutting down the are pump loss .

The bending fretting fatigue tests of 316L austenitic stainless steel, 7075 aluminum alloy, LZ50 steel and 30CrNiMo8 steel have been carried out under different bending stresses and normal contact stresses. The S – N curves of varied materials are set up accordingly, which present the shape like the Greek letter “e” and can be divided into three running regimes similar to fretting wear. Based on the OM, SEM, EDS and TEM, the fretting fatigue damages have been analyzed in detail. The fretting wear damage mechanisms of fretting zone are abrasive wear, oxidative wear and delamination, a damage physical model in the MFR is proposed. According to the TEM results, two crack initiation mechanisms have been proposed based on different material characteristics.

The experimental study of unload on temperature characteristics is put up for heavy vehicle hydraulic retarder, forms the retarder unload testing method of temperature characteristics, confirms the relationship between the temperature of hydraulic retarder inner cavity and unload torquecavity air density, which can be used to instruct the simulation of retarder inside flow field in unload condition and actualize method to reduce air losing, and it lays the foundation for developing mechanism research to reduce air losing of retarder.

Qing Dynasty rulers for political and social needs of the consideration, in the Eight Banners school tried to maintain the horsemanship and archery education, and to develop the important management measures to maintain the effective operation of the horsemanship and archery education. These management features include: the specialized management institutions and experienced management personnel; the strict examination for horsemanship and archery education, and rewards and punishments; object of rewards and punishments include the students, and teacher.

We developed a method that involved an asymmetric conjugate addition of secondary phosphines to α,β-unsaturated enones bearing β-2-pyridyl substituents catalyzed by a PCP pincer–Pd complex. The technique was established for the preparation of chiral P,N-compounds in excellent enantioselectivity (up to 99% ee) under mild conditions.

OBJECTIVE Although plenty of researchers have reported systemic effects originating from chronic periodontitis (CP) on potentially distal inflammatory processes, such as those leading to coronary heart disease, cerebrovascular disease, and cancer, no study has reported the association between CP and sudden sensorineural hearing loss (SSNHL). The present study explored the association between CP and SSNHL using a large, population-based dataset in Taiwan. STUDY DESIGN A case-control study. SETTING Taiwan. PATIENTS We used administrative claims data from the Taiwan National Health Insurance program to identify 2,436 subjects with SSNHL and to randomly select 7,308 controls. MAIN OUTCOME MEASURES A conditional logistic regression analysis was conducted to calculate the odds ratio (OR) for having been previously diagnosed with CP between cases and controls. RESULTS In total, 1,663 (17.1%) of the 9,744 sampled subjects had received a CP diagnosis before the index date; 520 (21.4%) were cases and 1143 (15.6%) were controls. The χ2 test suggested that there was a significant difference in the prevalence of previous SSNHL between cases and controls (p < 0.001). The conditional logistic regression revealed after adjusting for hypertension, diabetes, hyperlipidemia, renal disease, coronary heart disease, obesity, and stroke, the OR of having previously received a CP diagnosis among cases was 1.44 (95% CI = 1.29∼1.63) that of controls. CONCLUSION This study found that SSNHL was significantly associated with a previous diagnosis of CP. Further prospective studies are warranted to confirm our findings and clarify the underlying pathomechanism.

In this paper, we conduct a comprehensive survey on the past developments and recent advances of bilevel programming models, algorithms and practical applications in urban transportation network design problems. Moreover, based on this survey, some open problems and future research directions are proposed.

Severe fever with thrombocytopenia syndrome (SFTS), a new disease of zoonotic natural foci has been increasing in recent years. In this review, the disease of human granulocytic anaplasmosis infection due to tickborne and new Bunia virus infection, have similar clinical symptoms. Total of 11 articles were retrieved. The emergence, etiology, nomenclature and pathogenic mechanisms, clinical diagnosis and genotyping of SFTS were summarized, and the current situation of treatment was also evaluated. In conclusion, early detection, identification and treatment are the key points to SFTS, but how to reduce the mortality of critically ill patients is still the focus in the future.

Fretting damage failure analysis of a Chinese carbon railway axle RD 2 was carried out. Thewheelhubwasinsitucuttoexposethedamagedsurfaceofthewheelseattoavoidadditionaldamage. A small-scale axle test rig was developed, and simulation tests were performed atdifferent rotator speeds of 1800 and 2100rpm. The wear mechanism of fretting damageareaswasacombinationofabrasivewear,oxidativewearanddelamination.Thefracturesur-faces exhibited characterization of multisource and step-profile. The fretting fatigue crackinitiated at the subsurface and propagated along an inclined angle at the first stage. Thefrettingdamageatthehigherspeedwas moreseverecompared withthelowerspeed,whichlead to a relatively shorter fatigue life. The damage morphologies of the axle in the simula-tion tests were in good agreement with that observed in the failure analysis on real axle. Keywords failure analysis; fretting fatigue; press-fitted; railway axle; rotatory bending.NOMENCLATURE BE = binding energyE = Young's modulusFWHM = full width at half maximumHV

Objectives/Hypothesis Although chronic periodontitis (CP) and chronic rhinosinusitis (CRS) both share immunological disturbances as pathological factors, no prior study has investigated the risk for CP among patients with CRS. This study set out to provide an estimation of risk by utilizing a cohort study design to leverage the statistical power of a population-based dataset in Taiwan. Study Design A retrospective cohort study. Methods In total, 13,782 CRS subjects were included in the study cohort and 41,346 subjects were randomly extracted for the comparison cohort. We individually tracked each subject in this study (N = 55,128) for a 5-year period following their index date to identify those subjects who received a subsequent diagnosis of CP. Cox proportional hazards regression analysis was conducted to calculate the 5-year risk of subsequent CP following a diagnosis of CRS among the sampled subjects. Results The incidence rate of CP during the 5-year follow-up period was 5.12 (95% confidence interval [CI], 4.95-5.30) per 100 person-years and 3.24 (95% CI, 3.17-3.30) per 100 person-years for the study and comparison cohort, respectively. Cox proportional hazards regression revealed that the hazard ratio for CP during the 5-year follow-up period for subjects with CRS was 1.59 times (95% CI, 1.52-1.67) that of comparison subjects after adjusting for monthly income, geographic region, hypertension, diabetes, coronary heart disease, and hyperlipidemia, and censoring for cases who died during the 5-year follow-up period. Conclusions This study detected an increased risk for CP among patients suffering from CRS. CRS patients should be alerted to pay particular attention to their oral hygiene practices to prevent both CP and its downstream sequelae.

The microbiological transformation of the triterpene nigranoic acid (3,4-secocycloarta-4(28),24(Z)-diene-3,26-dioic acid) (1) to 3,4-secocycloarta-4(28),17(20),24(Z)-triene-7β-hydroxy-16β,26-lactone-3-oic acid (2) and 3,4-secocycloarta-4(28),17(20)(Z),24(Z)-triene-7β-hydroxy-16β-methoxy-3,26-dioic acid (3) by the freshwater fungus Dictyosporium heptasporum YMF1.01213 has been demonstrated. The structures of the biotransformation products were determined by spectroscopic and MS analyses. Compound 2, characterized by the presence of a formed C-16/C-26 ester bridge, provided a novel nine-membered lactone ring structural skeleton for 3,4-secocycloartane triterpenoid derivatives. In addition, Compounds 1-3 exhibited weak anti-HIV activity in vitro. Compounds 2 and 3 were reported for the first time as natural product derivatives.

GaMnN thin films were fabricated by using pulsed laser deposition followed by annealing. In our experiments, the impact of the background nitrogen pressure on the crystal quality, morphology and the ferromagnetism of the GaMnN thin films were studied systematically. It is found that the samples deposited at 0.75 Pa have the best crystal quality. All the annealed samples showed ferromagnetic behavior, and the Curie temperature was estimated up to 340 K. We found the magnetization of our samples changes depending on the concentration of Mn3+ ions, and the origin of the room temperature ferromagnetism of our samples can be explained by bound magnetic polaron theory. The nitrogen vacancies may cause the ferromagnetism to be weakened.

The ultrathin DLC coatings with thickness of 2 nm and 5 nm were deposited onto Si(100) substrate by the filtered cathodic arc technique. The nanowear tests were performed on DLC coatings and Si(100) substrate by diamond tip and SiO 2 microspheric tips. The results indicated that the coatings could support an indentation with a peak contact pressure of 7 GPa. During scratch tests, the critical load corresponding to the generation of grooves on silicon substrate could be raised by 75%/125% after the deposition of DLC coating of 2 nm/5 nm in thickness. When the nanowear tests were conducted by a diamond tip, DLC coatings could effectively resist the mechanical wear and prevent the formation of hillock on silicon substrate. Moreover, since two DLC coatings present a close coverage on silicon substrate, they can largely resist the tribochemical wear of silicon substrate by SiO 2 tip in humid air. Under a contact pressure of 1.3 GPa, the wear depth on 2 nm/5 nm DLC coating was only 0.42 nm/0.28 nm, which was less than 5% of that on silicon substrate. Finally, either in humid air or in vacuum, 2 nm DLC coating presented the excellent durability to protect the silicon substrate from wear damage. Therefore, although thicker DLC coating to some extent reveals better wear resistance, 2 nm DLC coating is enough to protect its substrate against nanowear.

By using an atomic force microscopy, the wear tests of Si(100) surface against SiO 2 microsphere were performed both in water and in air. During the tests, the contact pressure was varied between 0.78 GPa and 1.1 GPa, the displacement amplitude was set as 250 nm and the number of wear cycles was 200. As a comparison, the wear tests of Si(100) surface against diamond tip were also performed in water and air. The experimental results indicated that water environment played an important role in the wear behaviour of Si/SiO 2 pair. Under a contact pressure of 1.1 GPa, the wear depth of silicon in water was about 0.25 nm, which was less than 10% of that in air. Since the wear depths of silicon in water were similar at various velocities (0.04–5 μm/s), the hydrodynamic lubrication was not the main reason causing the slight wear of silicon in water. Further analysis indicated that the distinct wear behaviour of Si/SiO 2 pair in air and in water could be mainly explained as the different intensity of chemical reactions in two environments for the pair of Si/SiO 2 . In air, the SiOSi bridges could easily form between SiO 2 microsphere and silicon substrate and induced serious tribochemical wear of silicon. When the Si/SiO 2 pair was immersed in water, the tribochemical reaction was largely resisted by the electrical double layer and the wear of silicon was slight. Even though, since the contact pressure was too low to induce the mechanical wear of silicon, the limited wear of silicon in water was still attributed to the tribochemical reaction. The results may help us understand the nanowear mechanism of silicon and optimize the tribological design of dynamic MEMS working in water environment.

Dual-rotary fretting (DRF) is a complex fretting wear mode combining torsional mode with rotational mode. With the contact configuration of ball-on-flat (7075 aluminum alloy flats against AISI 52100 steel balls), the DRF wear tests in oil and water were carried out respectively under varied rotary angular displacement amplitudes and tilt angles. By combining the dynamic behavior analyses with damage morphology examinations, the wear mechanisms of DRF in dry condition, oil and water were analyzed in detail. Compared with the dry friction condition, both oil and water acted as lubricants and played an important role during the running and damage processes of DRF, which significantly changed the fretting running regimes and third-body behaviors. It is found that the oil media can effectively mitigate DRF damage, especially when the tilt angle and the angular displacement amplitude are large, because the oil can penetrate into the contact interface and form a lubricant film. Relatively, the water can easily penetrate into the micro-cracks on the surface and promote the propagation of cracks because the viscosity of water is low. Therefore, the delamination is more obvious in the water.

Bending fretting fatigue tests of 7075 aluminum alloy cylinders against 52100 steel cylinders orthogonally have been carried out under a same normal load and varied bending loads. The S–N curve of the bending fretting fatigue showed a characteristic of “C curve”. Based on the OM, SEM, and TEM, the fretting fatigue damages of 7075 alloy have been analyzed in detail. A physical model was set up to describe the surface damage and the crack formation process in MFR. The TEM analyses showed that the stress concentration at the wall of dislocation cells was the reason of the fatigue crack initiation.

By using an atomic force microscopy, the wear tests of Si(100) surface against SiO 2 microsphere were performed both in water and in air. During the tests, the contact pressure was varied between 0.78 GPa and 1.1 GPa, the displacement amplitude was set as 250 nm and the number of wear cycles was 200. As a comparison, the wear tests of Si(100) surface against diamond tip were also performed in water and air. The experimental results indicated that water environment played an important role in the wear behaviour of Si/SiO 2 pair. Under a contact pressure of 1.1 GPa, the wear depth of silicon in water was about 0.25 nm, which was less than 10% of that in air. Since the wear depths of silicon in water were similar at various sliding velocities (0.04–5 μm/s), the hydrodynamic lubrication was not the main reason causing the slight wear of silicon in water. Further analysis indicated that the distinct wear behaviour of Si/SiO 2 pair in air and in water could be mainly explained as the different intensity of chemical reactions in two environments for the pair of Si/SiO 2 . In air, the SiOSi bridges could easily form between SiO 2 microsphere and silicon substrate and induced serious tribochemical wear of silicon. When the Si/SiO 2 pair was immersed in water, because of the different structure of the adsorbed water layer on silicon surface and the effect of the electrical double layer, the tribochemical reaction was largely resisted and the wear of silicon was slight. Even though, since the contact pressure was too low to induce the mechanical wear of silicon, the limited wear of silicon in water was still attributed to the tribochemical reaction. The results may help us understand the nanowear mechanism of silicon and optimize the tribological design of dynamic MEMS working in water environment.

Objectives/Hypothesis: It has been recognized that chronic rhinosinusitis (CRS) involves intracranial vessels and may be associated with stroke occurrence. However, the detailed epidemiological profile of stroke risk among patients with CRS is still not well understood. Therefore, this study aimed to explore the frequency and risk for stroke among patients with CRS by conducting a large scale population-based cohort study in Taiwan. Methods: All study cohorts were retrieved from the Taiwan Longitudinal Health Insurance Database. This study included 15,846 CRS subjects in the study cohort and 47,538 randomly selected subjects in the comparison cohort. We individually tracked each subject in this study for a 5 year period following their index dates to identify each subject that received a subsequent diagnosis of stroke. Stratified Cox proportional hazards regressions were analyzed to compare the 5 year risk of subsequent stroke following a diagnosis of CRS. Results: The incidence rate of stroke during the 5-year follow-up period was 10.65 (95% CI: 9.93–11.41) per 100 person years and 7.53 (95% CI: 7.18–7.89) per 100 person years for the study and comparison cohort, respectively. The covariate-adjusted hazard ratio (HR) for stroke revealed that that subjects with CRS were more likely than comparison subjects to have a diagnosis of ischemic stroke during the 5-year follow-up period (HR = 1.34, 95% CI = 1.18–1.53). However, there was no significant difference in the risk of subarachnoid hemorrhage (HR = 1.52, 95% CI = 0.94–2.47) or intracerebral hemorrhage (HR = 0.96, 95% CI = 0.71–1.31). Conclusions: Patients with CRS were at higher risk for stroke occurrence during the 5 year follow-up.

Using the integrated method of finite element and multi-body dynamics to build leaf spring model considering assembly pre-stress. Based on the stiffness testing platform, the simulation platform has been built. Finally , the experiment results verified the stiffness simulation results. The results show that the leaf spring model considering assembly pre-stress accords to the leaf spring property，the simulation result agrees with the experiment result and verify the accuracy of the modeling method. The results from the stiffness simulation platform and the test platform have high consistency, so the simulation platform can be used for the stiffness testing of leaf spring like this.

Being a widely used clean and renewable energy, the wind power has attracted the attention of all nations in the world. The application of air cooled close-loop self-circulation evaporative cooling technology in the cooling of large wind power generator is a new attempt in the discovery of wind power energy. The structure of the air cooling condenser has great effect on the smooth running of the natural temperature close-loop self-circulation (CLSC) evaporative cooling system of large wind power generator. An optimum structure of the air cooling condenser for the evaporative cooling system is introduced in this paper which can do great help to insure the successful running of wind generator. All these will do great help to the development of the evaporative cooling large wind power generator.

Aim This study set out to explore the association between obstructive sleep apnoea (OSA) and prior chronic periodontitis (CP) by utilizing a population-based data set with a case-control design in Taiwan. Materials and Methods We included 7673 subjects with OSA as cases, and randomly selected 21,963 subjects without a history of OSA as controls. We performed conditional logistic regression analyses to explore the association between OSA and having been previously diagnosed with CP. Results There was a significant difference in the prevalence of prior CP between cases and controls (33.8% versus 22.6%, p

Regioregular head-tail poly(3-hexylthiophenes) (HT-P3HT) with a controlled high molecular weight and a small polydispersity have been synthesized via an improved Kumada catalyst-transfer polycondensation (KCTP) by using the new-prepared hexylmagnesium bromide as the Grignard reagent. As the amount of nickel catalyst dichloro[1,3-diphenylphosphinopropane] nickel (Ni(dppp)Cl2) was 0.5% mol of the amount of monomer 2,5-dibromo-3-hexylthiophene (DBHT) we can obtain a HT-P3HT with a high molecular weight Mn (38 449) and a small polydspersity (1.18). By using of LiCl as a co-catalyst, the regioregularity of the P3HT with high molecular weight (40 270) is maintained and the PDI (1.03) is smaller than that of the P3HT polymerized in the absence of LiCl but the conversion ratio of the monomer is promoted. The HT-P3HT with high molecular weight and small polydispersity will be an attractive candidate applied in solar cells.

The Mn-doped GaN (GaMnN) films on c-plane sapphire substrates were prepared by using Laser Molecular Beam Epitaxy (LMBE) at different base nitrogen pressure, followed by annealing in the ammonia atmosphere at 950 °C for 30 min, to study the original reason of the room-temperature ferromagnetism of GaMnN films. We found the crystalline quality was sensitive to the base nitrogen pressure during growth. X-ray photoelectron spectra (XPS) analysis confirmed that the Mn3+ and Mn2+ coexist in our samples. The room-temperature ferromagnetic behavior can be explained by double exchange. The ferromagnetism would be weakened by the nitrogen vacancies, which plays a role of donor.

This paper presents the preparation of bimodal crystalline macro-/mesoporous titania powders by using a pluronic polymer (EO20PO70EO20, P123) as a template through a hydrothermal treatment. The as-prepared powders were characterized by X-ray diffraction (XRD), nitrogen adsorption-desorption, scanning electron microscope (SEM) and transmission electron microscope (TEM). The results reveal that the amount of P123 has a significant effect on the surface area of the mesoporous titania. When the mass ratio of P123:TBOT is 1:14, the crystalline macro-/mesoporous titania has the largest surface area (120.96 m2/g), the average pore diameter of this sample reaches a minimum of 6.67 nm.

Objectives The study aimed to estimate the risk of developing chronic rhinosinusitis (CRS) among children who had undergone a tonsillectomy by utilizing a cohort study based on a population-based database. Methods Data for this retrospective cohort study were sourced from the Taiwan ”Longitudinal Health Insurance Database 2000”. We included 202 children who had undergone a tonsillectomy as the study group and 2020 sex- and age-matched children as the comparison group. We used stratified Cox proportional hazard regressions to calculate the hazard ratio (HR) and its corresponding 95% confidence interval (CI) for CRS during the 3-year follow-up period. Results Of 2222 sampled children, the incidence rate of CRS during the 3-year follow-up period was 3.2 (95% CI = 2.0–4.8) 1000 person-years; 18.2 (95% CI = 9.1–32.5) per 1000 person-years and 1.7 (95% CI = 0.8–3.0) per 1000 person-years for the study and comparison group, respectively. The stratified Cox proportional analysis showed that the adjusted hazard ratio for CRS during the 3-year follow-up period was 8.28 (95% CI = 3.24–21.16) for children who had undergone a tonsillectomy than comparison patients. Conclusions We demonstrated that the risk of developing CRS is significantly increased among children who have undergone a tonsillectomy.

A novel polarization insensitive metasurface for monostatic Radar Cross Section (RCS) reduction is designed, fabricated, and investigated. The proposed metasurface is comprised of carefully arranged unit cells with spatially varied dimension, which enables approximate uniform diffusion of incoming electromagnetic energy and avoids reflection at the specular direction. A theoretical model based on reflectarray theory is introduced to demonstrate the operating principle of the metasurface. By utilizing Gravitational Search Algorithm (GSA) and a fast far-field scattering pattern analysis method based on Inverse Fast Fourier transform technology (IFFT), a rapid and efficient design method is demonstrated. A metasurface sample is fabricated and tested to validate RCS reduction behavior predicted by full wave simulation. An over 20dB RCS reduction is observed in the vicinity of 9.5GHz, indicating our metasurface may be potentially applied in future stealth technology.

Palatoplasty can significantly decrease their middle ear re-intubation rate with a relatively lower hazard ratio compared to children who underwent VTI only.In children with cleft palate, questions remain about the overall effect of ventilation tube insertion (VTI) and palatoplasty for their OME. A large-scale study might offer more evidence for the roles of palatal surgery.This was a retrospective birth cohort study based upon a national database. We analyzed children born between 1999-2004 and diagnosed as cleft palate and/or lips. These children, according to their surgeries, were separated into two groups: (1) VTI only, and (2) VTI and palatoplasty. Kaplan-Meier analysis and log-rank test were used to calculate their cumulative tube re-insertion rates. Their hazard ratios of tube re-insertion were also analyzed.In total, 1205 cleft children were collected, with 151 in the VTI only group and 1054 in the VTI + palatoplasty group. Ventilation tube re-insertion rates were significantly lower in the VTI + palatoplasty group (p = 0.002). The cumulative re-insertion rates also showed a significant difference (p = 0.001). When compared to the VTI only group, the adjusted hazard ratio was 0.528 in the VTI + palatoplasty group (p = 0.001).

In today's data center, in order to achieve higher density and better energy efficiency, the traditional server systems with dedicated fans and power supply units are evolving to the Rack Scale System with shared cooling and shared power supply at rack level, some examples are Open Compute Project and China Scorpio Rack. This evolution brings the challenges of how to efficiently control the rack cooling and effectively manage the rack power at coarse granularity level, e.g. at the whole rack or half rack level, while no increasing in system cost and management complexity. In this paper, the management architecture for the Rack Scale System is introduced, the cooling zone, power zone, and the parameters for thermal and power management are elaborated. Some new virtual sensors for thermal management are also introduced in this paper, the modeling method for the volumetric airflow virtual sensor is described, and the validation test results are presented. With the rack thermal and power management, the IT devices can be closely associated with the datacenter facilities, and thus be intelligently orchestrated and adapted to the workload for TCO (Total Cost of Ownership) saving and reliability improvement.

The relationship between obstructive sleep apnea (OSA) and chronic rhinosinusitis (CRS) still remains unclear. This retrospective cohort study aimed to investigate the relationship between OSA and subsequent CRS using a population-based dataset. The study used data from the Taiwan Longitudinal Health Insurance Database 2005. We selected 971 patients with OSA for the study cohort and 4855 patients without OSA for the comparison cohort. Each patient was tracked for 5 years to determine those who were subsequently diagnosed with CRS. Stratified Cox proportional hazard regression analyses were performed to examine the association of OSA with subsequent CRS. The results revealed that 161 (2.76%) of the total sampled patients were subsequently diagnosed with CRS. Subsequent incidences of CRS were found in 64 (6.59%) patients with OSA and 97 (2.00%) patients without OSA. The adjusted hazard ratio (HR) of subsequent CRS for patients with OSA was 3.18 (95% confidence interval: 2.27~4.45) compared to those without OSA. Furthermore, the HR for CRS was similar for subjects with OSA for both genders (with an adjusted HR of 3.44 for males and 2.63 for females). We concluded that patients with OSA had a higher risk of subsequent CRS compared to patients without OSA regardless of sex.

Thin copper sheets as marker material were embedded into weld path of 2024 aluminium alloy plates and their final position after friction stir welding was examined by metallographic techniques. Referring to the visualized material flow patterns, a three-dimensional model was developed to conduct the numerical simulation of the temperature profile and plastic material flow in friction stir welding. The calculated velocity contour of plastic flow in close proximity of the tool is generally consistent with the visualized results. As the tool rotation speed increases at a constant tool travel speed, the material flow near the pin gets stronger. The predicted shape and size of the weld nugget zone match with the experimentally measured ones.

As a clean and renewable energy, the wind power has attracted the attention of all nations in the world. Evaporative cooling technology has successfully been used in the research and development of wind power generator, but some key technique has to be studied in advance to insure the reliability of the very technology. The application of evaporative cooling technology in the cooling of large wind power generator is a new attempt in the discovery of wind power energy. Thorough study is carried out on the key technique of the application of close-loop self-circulation (CLSC) evaporative cooling technology on the running of wind power generator. The flow resistance of the coolant in the air cooling condenser is discussed in this paper, and a new approach is founded for the improvement of the reliability.

Objective To explore the effect of perivascular sympathetic nerve on cerebral collateral arteriogenesis in chronic cerebral hypoperfusion models of rats. Materials and Methods Chronic cerebral hypoperfusion model was established by right common carotid artery ligation for 8 weeks, while sympathetic denervation was performed by superior cervical ganglionectomy. The male Sprague-Dawley rats were randomly divided into 4 groups including sham group ( n = 21), denervation group ( n = 21), artery ligation group ( n = 21) and combined group with both artery ligation and denervation ( n = 21). After 8 weeks of surgery, the rats in each group were randomly divided into 3 subgroups including subgroup A ( n = 7), subgroup B ( n = 7) and subgroup C ( n = 7). The 3 subgroups were subjected to latex perfusion, permanent right middle cerebral artery occlusion and immunohistochemical staining, respectively. Results The diameters of right leptomeningeal anastomoses in artery ligation group significantly enlarged compared with sham group. When sympathetic denervation was performed in the presence of artery ligation, diameter of collateral vessel decreased, although larger than in sham group. After 8 weeks of permanent right middle cerebral artery occlusion, the cerebral perfusion over the right middle cerebral artery area in combined group was significantly lower than in artery ligation group, although both were higher than in denervation group and sham group. Triphenyltetrazolium chloride staining showed that cerebral infarct volume in combined group was significantly larger than in artery ligation group, and smaller than in denervation group and sham group. Neurologic functional scoring showed that scores in combined group were significantly higher than in artery ligation group, and lower than in denervation group and sham group. Immunohistochemical staining for α-smooth muscle actin showed that compared with sham group, tunica media thickness of right leptomeningeal anastomoses in artery ligation group increased significantly. Thickness in combined group was thinner than in artery ligation group, although thicker than in sham group. Conclusions Perivascular sympathetic denervation can impair the cerebral collateral arteriogenesis under condition of chronic cerebral hypoperfusion.

ZnMgO thin films have been deposited on Si(111) substrates by pulsed laser deposition (PLD) technique at growth temperature from 300 to 700°C in nitrogen ambient of 1.0 Pa. The effects of growth temperature on structural and optical properties of deposited ZnMgO thin films have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), infrared absorption (IR) spectra and photoluminescence (PL) spectra. The results of XRD and SEM analyses show that the film fabricated at 400°C possesses good crystallinity with hexagonal wurtzite structure and surface morphology. The Mg has been incorporated into ZnO in the form of substitutional Zn. The IR spectra reveal the typical absorption peaks of ZnMgO. The band-gap values have been obtained from 2.96 to 4.23 eV with increasing growth temperature. The PL spectra show that the highest UV emission is obtained at growth temperature of 600°C, and the obvious blue-shift is observed. This may be assigned as the change of the band-gap due to the increasing incorporation of Mg2+ ions with the increasing growth temperature.

Bending fretting fatigue tests of 316L austenitic stainless steel plates against 52100 steel cylinders have been carried out under same normal load and varied bending loads. Tests of plain bending fatigue were carried out as a control group. The S – N curves of the bending fatigue were made. The results indicated that there was an obvious drop of life under the condition of bending fretting fatigue due to higher local contact stress. A dislocation model of micro-crack nucleation mechanism, as a manner of zig-zag mode, was created to explain the nucleation of fretting fatigue cracks.

A natural mineral, palygorskite clay, was used to synthesize pure zeolite X via a two-stage method. The synthetic parameters, such as calcination, crystallization time, and SiO2/Al2O3molar ratio, were investigated. The results indicated that calcination enhanced the extraction of silica from palygorskite clay and was beneficial for the formation of zeolite X. Micro-sized pure zeolite X with the particle size of 1-4 μm was obtained in the gel with the SiO2/Al2O3molar ratio range of 1.93 to 3 after hydrothermal treatment at 80 °C for 5 h. The synthetic zeolite X showed high specific surface area (487 m2/g) and low Si/Al ratio (1.17).

In order to further study the mechanism of hydrolysis reactions to sugars using cornstalk on plasma, preliminary study of reactive process are carried out. Model compounds of cornstalk components are chosen and hydrolyzed on plasma. Activation energy of elementary reactions, which are single-molecule reactions, free radical reactions and bimolecular reactions, are calculated by bond energy percentage rules. Elementary reactions and preliminary reaction mechanism model, which cornstalk hydrolyzes to sugars on plasma are identified.

Objectives: The primary aim of this study was to obtain the mean hearing thresholds among school-age children residing in the Datong and Jhongshan Districts of Taipei City, Taiwan. Design: Hearing thresholds were obtained from a stratified sample of 1411 students in grades 1, 4, 7, and 10 based on their participation in the annual health examination of school-age children carried out by the Taipei City Government. After otoscopic examination, audiometric testing was undertaken at 0.5 to 4 kHz along with tympanometric screening. The means and SDs obtained from these examinations are reported by grade, gender, ear, and frequency. Results: The mean hearing thresholds ranged between 6.8 and 16.7 dB HL, with the highest (poorest) hearing threshold being obtained at a test frequency of 0.5 kHz. At all the tested frequencies, the hearing thresholds of boys were found to be higher than those of girls. Logistic regressions demonstrating that those students with the highest odds ratios of hearing loss were to be found in the sample of children in grade 1. The odds ratios of hearing loss were also found to be higher among boys than girls and for the left ear rather than the right. Conclusions: These results indicate that the mean thresholds among the study sample were well above (meaning poorer) the pure-tone average of 15 dB HL, as recommended in a previous study. Therefore, the results of this study suggest the need to further determine the etiology of hearing loss among children in grades 1, 4, 7, and 10 in the Datong and Jhongshan Districts of Taipei City and perhaps Taiwan.

In order to obtain good welding quality, it is necessary to apply quality control because there are many influencing factors in laser welding process. The key to realize welding quality control is to obtain the quality information. Abundant weld quality information is contained in weld pool and keyhole. Aiming at Nd:YAG laser welding of stainless steel, a coaxial visual sensing system was constructed. The images of weld pool and keyhole were obtained. Based on the gray character of weld pool and keyhole in images, an image processing algorithm was designed. The search start point and search criteria of weld pool and keyhole edge were determined respectively.