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Improvement of environmental cleaning in hospitals has been shown to decrease in-hospital cross transmission of pathogens. Several objective methods, including aerobic colony counts (ACCs), the adenosine triphosphate (ATP) bioluminescence assay, and the fluorescent marker method have been developed to assess cleanliness. However, the standard interpretation of cleanliness using the fluorescent marker method remains uncertain.
To assess the fluorescent marker method as a tool for determining the effectiveness of hospital cleaning.
A prospective survey study.
An academic medical center.
The same 10 high-touch surfaces were tested after each terminal cleaning using (1) the fluorescent marker method, (2) the ATP assay, and (3) the ACC method. Using the fluorescent marker method under study, surfaces were classified as totally clean, partially clean, or not clean. The ACC method was used as the standard for comparison.
According to the fluorescent marker method, of the 830 high-touch surfaces, 321 surfaces (38.7%) were totally clean (TC group), 84 surfaces (10.1%) were partially clean (PC group), and 425 surfaces (51.2%) were not clean (NC group). The TC group had significantly lower ATP and ACC values (mean ± SD, 428.7 ± 1,180.0 relative light units [RLU] and 15.6 ± 77.3 colony forming units [CFU]/100 cm2) than the PC group (1,386.8 ± 2,434.0 RLU and 34.9 ± 87.2 CFU/100 cm2) and the NC group (1,132.9 ± 2,976.1 RLU and 46.8 ± 119.2 CFU/100 cm2).
The fluorescent marker method provided a simple, reliable, and real-time assessment of environmental cleaning in hospitals. Our results indicate that only a surface determined to be totally clean using the fluorescent marker method could be considered clean.
This paper reports the measurement of the energy loss of protons at the energy of 100 keV penetrating a partially ionized hydrogen plasma. The plasma of ne ≈ 1015–16 cm−3; Te ≈ 1–2 eV and lifetime of about 8 µs is created by the hydrogen gas discharge. The experimental results show an increase of a factor of 2.8 in the energy loss, which are in good agreement with the Bethe, Standard Stopping Model, Li–Petrasso and Vlasov models’ predictions within the error limit. The Bethe–Bloch Coulomb logarithm term is found to increase by a factor of 4.0 for free electrons as compared with the situation where bound electrons prevail. The potential application of protons energy loss for diagnosing the electron density in plasma is proposed too.
The purpose of this study was to investigate the effects of 8-week green tea extract (GTE) supplementation on promoting postexercise muscle glycogen resynthesis and systemic energy substrate utilisation in young college students. A total of eight healthy male participants (age: 22·0 (se 1·0) years, BMI: 24·2 (se 0·7) kg/m2, VO2max: 43·2 (se 2·4) ml/kg per min) participated in this study. GTE (500 mg/d for 8 weeks) was compared with placebo in participants in a double-blind/placebo-controlled and crossover study design with an 8-week washout period. Thereafter, all participants performed a 60-min cycling exercise (75 % VO2max) and consumed a carbohydrate-enriched meal immediately after exercise. Vastus lateralis muscle samples were collected immediately (0 h) and 3 h after exercise, and blood and gaseous samples were collected during the 3-h postexercise recovery period. An 8-week oral GTE supplementation had no effects on further promoting muscle glycogen resynthesis in exercised human skeletal muscle, but the exercise-induced muscle GLUT type 4 (GLUT4) protein content was greater in the GTE supplementation trial (P<0·05). We observed that, during the postexercise recovery period, GTE supplementation elicited an increase in energy reliance on fat oxidation compared with the placebo trial (P<0·05), although there were no differences in blood glucose and insulin responses between the two trials. In summary, 8-week oral GTE supplementation increases postexercise systemic fat oxidation and exercise-induced muscle GLUT4 protein content in response to an acute bout of endurance exercise. However, GTE supplementation has no further benefit on promoting muscle glycogen resynthesis during the postexercise period.
Cellulose nanocrystals (CNCs) are high-strength sustainable nanomaterials, the
incorporation of which to a host polymer matrix can potentially lead to
nanocomposites with superior mechanical properties. However, the mismatch in
surface energy of CNCs and common structural polymers is a challenge that needs
to be overcome to prevent the aggregation of CNCs and ensure the robust
integration of CNCs into a polymer matrix. Herein, we report an approach
involving the functionalization of CNCs with maleated-anhydride polypropylene
(MAPP) through diethylenetriamine (DETA) linkers to significantly enhance the
compatibility between CNCs and polypropylene. Polypropylene/modified CNC
nanocomposites displayed 74% and 76% increase in elastic modulus in comparison
to neat polypropylene and polypropylene/untreated CNC nanocomposites,
respectively. The tensile strength was also higher for nanocomposites with
modified CNC than neat polypropylene, as well as nanocomposites with untreated
CNCs. The tensile strength at 5.5% strain of polypropylene/modified CNC
nanocomposites was 32% and 28% larger that of polypropylene and
polypropylene/untreated CNC nanocomposites, respectively. Finally, such
CNC-based nanocomposites have a lower density than many competitive systems
resulting in opportunities to propagate this environmentally-responsible
technology to nanocomposites used in additive manufacturing, automotive
applications, construction materials and consumer products.
We investigated the electrical properties of the rf-sputtered HfxZn1-xO/ZnO heterostructures. The thermal annealing on ZnO prior to the HfxZn1-xO deposition greatly influences the properties of the heterostructures. A highly conductive interface formed at the interface between HfxZn1-xO and ZnO thin films as the ZnO annealing temperature exceeded 500°C, leading to the apparent decrease of the electrical resistance. The resistance decreased with an increase of either thickness or Hf content of the HfxZn1-xO capping layer. The Hf0.05Zn0.95O/ZnO heterostructure with a 200-nm-thick 600°C-annealed ZnO exhibits a carrier mobility of 14.3 cm2V-1s-1 and a sheet carrier concentration of 1.93×1013 cm-2; the corresponding values for the bare ZnO thin film are 0.47 cm2V-1s-1 and 2.27×1012 cm-2, respectively. Rf-sputtered HfZnO/ZnO heterostructures can potentially be used to increase the carrier mobility of thin-film transistors in large-area electronics.
The encapsulation failure is a serious problem which leads to power degradation and life time reduction of silicon based thin film solar module. Therefore, the encapsulation material and related technology research and development become more and more important. This article describes some different junction box and middle foil encapsulation technology of the silicon based thin film solar module, different encapsulation materials and processes are compared and their impact on the manufacturing cost and module performance are discussed. The aim of this study is to find an appropriate solution of module encapsulation failure.
A novel allergy biosensor is designed and fabricated by using thin film bulk acoustic resonator (TFBAR) devices with shear mode ZnO piezoelectric thin films. To fabricate TFBAR devices, the off-axis RF magnetron sputtering method for the growth of piezoelectric ZnO piezoelectric thin films is adopted. The influences of the relative distance and sputtering parameters are investigated. In this report, the piezoelectric ZnO thin films with tilting angle are set by controlling the deposition parameters. The properties of the shear mode ZnO thin films are investigated by X-ray diffraction and scanning electron microscopy. The frequency response is measured using an HP8720 network analyzer with a CASCADE probe station. The resonance frequency of the shear mode is 796.75 MHz. The sensitivity of the shear mode is calculated to be 462.5 kHz·cm2/ng.
The significant time older people typically spend at home affects both their level of physical activity and quality of life. This prospective cohort study was designed to identify the effects that living in a high-rise residence retirement community has on physical activity and quality of life in older people with leprosy. The relocation group was comprised of study participants who had relocated voluntarily to a high-rise apartment building. The comparison group was comprised of study participants who had chosen not to relocate to that building. Data were collected using a personal information survey, Modified Baecke's Questionnaire, and the brief version of the World Health Organization Quality of Life assessment (WHOQOL-BREF). The groups were significantly similar in terms of household activities, leisure time activities, total physical activity score, and quality of life physical and social aspects, and significantly different in terms of quality of life overall (F=7.864, p=0.006), psychological (F=5.403, p=0.021) and environmental (F=23.099, p=0.000) aspects. This study indicates that living in a high-rise apartment environment does not decrease physical activity and may promote overall quality of life, and psychological and environmental aspects, in retirement community residents. The findings enhance understanding of the effect of different living environments on physical activity and quality of life. Greater health professional participation in retirement community design to ensure such designs facilitate residents’ health and quality of life is recommended.
MgZnO becomes amorphous or short-range-ordered with the addition of hafnium oxide. The films are rf-sputter deposited onto glass substrates (Eagle 2000, Corning Inc.) from Mg0.05HfxZn0.95-xO targets (x=0, 0.025, 0.05, 0.075, 0.1) in pure Ar ambient at room temperature. The sputtered Mg0.05Zn0.95O exhibits strong (002) preferred orientation with XRD peak located at 2θ=34.16o. The XRD peak intensity is also greatly reduced, indicating the material amorphorization proceeds with the addition of Hf. The grain size, estimated from the full-width-at-half-maximum (FWHM) of the (002) XRD peak, decreases from 24.1 to 3.3 nm as the Hf content x increases from 0 to 0.025 in Mg0.05HfxZn0.95-xO. No sharp XRD peaks are detected in the as-sputtered films when more than 5.0 at.% Hf are added into the materials. The films remain in amorphous or short-range-ordered states after annealing at 600 oC for 30 mins. All Mg0.05HfxZn0.95-xO films (100 nm in thickness) are highly transparent (> 80 %) in the visible region from 400 to 800 nm and have sharp absorption edges in the UV region. The tauc bandgap ΔE (eV), as a function of hafnium composition x, is fitted as ΔE=3.336+6.08x for room temperature as-deposited films, and ΔE=3.302+2.60x for films after 30 min 600 oC annealing. The annealing process decreases the bandgap shift caused by the incorporation of Hf in the materials.
Staggered bottom-gate hydrogenated nanocrystalline silicon (nc-Si:H) thin-film transistors (TFTs) were demonstrated on flexible colorless polyimide substrates. The dc and ac bias-stress stability of these TFTs were investigated with and without mechanical tensile stress applied in parallel to the current flow direction. The findings indicate that the threshold voltage shift caused by an ac gate-bias stress was smaller compared to that caused by a dc gate-bias stress. Frequency dependence of threshold voltage shift was pronounced in the negative gate-bias stress experiments. Compared to TFTs under pure electrical gate-bias stressing, the stability of the nc-Si:H TFTs degrades further when the mechanical tensile strain is applied together with an electrical gate-bias stress.
Taiwan Photon Source (TPS) is under construction at the National Synchrotron Radiation Research Center (NSRRC). This 518 m circumference synchrotron accelerator will generate 3 GeV and 500 mA high-energy X-rays. Absorbers in the storage ring will receive relatively high power densities (at a distance of 2.2 m from the dipole source). Three types of crotch absorbers for B1–B3 storage chambers were designed and prototyped. An end absorber in B3 is also designed and implemented to protect the downstream components in the chamber from being heated by the synchrotron radiation. Intensive vacuum brazing between Oxygen Free High Conductivity copper (OFHC) and stainless steel was carried out while fabricating the absorber assembly. The analysis, design and construction of several absorbers are reported in this paper.
The meta-foil is an all-metal self-supported electromagnetic metamaterial that features a space-grid that is locally stiff, yet globally flexible. Owing to its mechanical, thermal, chemical and radiative robustness, it lends itself to widespread applications.
National Synchrotron Radiation Research Center (NSRRC) in Taiwan has initialized the construction of Taiwan Photon Source (TPS) synchrotron accelerator project. This 3 GeV, 500 mA beam current third-generation synchrotron accelerator will have a total of seven insertion device beam lines at day 1 after commissioning. That is, there will be one 2 × EPU48, five IU22 and one U5 undulator beamline. Corresponding front end components such as fixed masks, photon beam position monitor, photon absorber, slits and heavy metal shutter have been designed; manufacturing of these subsystems are on the way. Several prototype assemblies are completed, tested and will be reported in this paper.
Betel-nut use is associated with metabolic syndrome and obesity. However, the association between betel-nut chewing and risk for chronic kidney disease (CKD) is unknown. The present study was conducted to determine the association between betel-nut chewing and CKD in men.
We retrospectively reviewed health-check records of 3264 men in a hospital-based cross-sectional screening programme from 2003 to 2006. CKD was defined as estimated glomerular filtration rate less than 60 ml/min/1·73 m2 calculated by the Modification of Diet in Renal Disease formula. Risk factors for CKD including diabetes, hypertension, BMI, smoking, alcohol consumption and age were also considered.
A total of 677 (20·7 %) men were found to have CKD and 427 (13·1 %) participants reported a history of betel-nut use. The prevalence (24·8 %) of CKD in betel-nut users was significantly higher than that (11·3 %) of participants without betel-nut use (P = 0·026). In multivariate logistic regression analysis with adjustments for age, hypertension, diabetes and hyperlipidaemia, betel-nut use was independently associated with CKD (P < 0·001). The adjusted odds ratio for betel-nut use was 2·572 (95 % CI 1·917, 3·451).
Betel-nut use is associated with CKD in men. The association between betel-nut use and CKD is independent of age, BMI, smoking, alcohol consumption, hypertension, diabetes and hyperlipidaemia.
Few studies have been conducted to investigate the influence of recombinant human erythropoietin (rhEPO) on the long-term prognosis of end-stage renal disease (ESRD).
A retrospective cohort study.
The largest regional hospital renowned for haemodialysis in northern Taiwan.
A total of 702 ESRD patients undergoing haemodialysis between 1993 and 2002 were evaluated.
The rate of overall use of rhEPO, vitamin D3 or Fe therapy was 62 %. The 10-year survival rate in patients with rhEPO supplementation was statistically more favourable than that in patients without rhEPO (hazard ratio (HR) = 0·38, 95 % CI 0·30, 0·47, P < 0·0001). Similar findings were noted for patients receiving vitamin D3 (HR = 0·36, 95 % CI 0·21, 0·64, P = 0.0004) and Fe (HR = 0·45, 95 % CI 0·33, 0·61, P < 0·0001). After adjusting for age, education and aetiology, the administration of rhEPO resulted in statistically significant improvements in long-term survival rate either with (HR = 0·30, 95 % CI 0·22, 0·42) or without (HR = 0·48, 95 % CI 0·38, 0·61) combined use of Fe or vitamin D3.
We demonstrated a reduction in long-term mortality related to supplementation therapy with rhEPO, vitamin D3 and Fe. The findings provide a justification for the administration of combined supplement therapy in patients undergoing haemodialysis.
ZnO has shown great promise for the application in optoelectronic devices. Since the modulation of conductivity is one of the key issues in device performances, we have applied the Monte Carlo method to analyze the mobility of poly-crystalline MgZnO/ZnO heterostructure thin film layer in this paper. The effects of the grain boundary scattering, ionized impurity scattering, as well as phonon scattering are considered. Our study shows that with a design of modulation doping by including the effects of spontaneous and piezoelectric polarization, the grain boundary potential can be suppressed to improve the mobility of the ZnO layer by order(s) of magnitude. Simulation results are also confirmed by our experimental works that polarization effects play an important role to attract carriers and to increase the mobility.
Pulsed THz wave spectroscopy using air as the THz wave emitter with the excitation of femtosecond laser provides intense (>100 kV/cm) and broadband THz waves (usable bandwidth from 0.3 to 11 THz). Using the air-biased-coherent-detection (ABCD) method, air can also coherently detect pulsed THz waves over a broadband spectrum. By utilizing these two technologies, we developed a prototype THz air photonics time-domain reflection spectrometer, and applied it on many materials in normal reflection geometry. Optical properties of CaCO3 crystals and several other samples in the THz range were studied. The system provided a signal-to-noise ratio (SNR) over 1000:1, with 0.1 cm−1 frequency resolution. The results acquired from both transmission and reflection measurements were then compared.
We analyzed the effect of electromechanical stressing on the electrical characteristics of hydrogenated amorphous silicon thin-film transistors. It had been shown that the TFTs, fabricated at 150 °C, respond to tension/compression by a rise/fall in electron mobility. In TFTs fabricated using the same process, a slight shift of threshold voltage was observed under prolonged high compressive strain and the gate leakage current slightly increases after ˜2% compressive strain. In general, the change of TFT performance due to pure mechanical straining is small in comparison to electrical gate-bias stressing. From the comparison among Maxwell stress (induced by electrical gate-bias stressing), mechanical stress (applied by bending), and drifting electrical force for passivated hydrogen atom, the most significant cause for the change of electrical characterization of a-Si:H TFTs should be the trapping charges inside the dielectric, under combined electrical and mechanical stressing. The mechanical stress does not act on Si-H bonds to drift hydrogen atoms, while it is mainly balanced by the rigid Si-Si networks in a-Si:H or a-SiNx. Therefore, mechanical stress has very little effect on the instability of low temperature processed a-Si:H TFTs.