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A tandem reaction for the synthesis of phenanthrenes from arynes and α-(bromomethyl)styrenes is reported. The transformation proceeds via an ene reaction of α-(bromomethyl)styrenes with arynes, followed by a [4 + 2] cycloaddition reaction. The reaction generates 9-benzylphenanthrene derivatives in moderate to excellent yields.

A Rh(III)-catalyzed tandem reaction for the synthesis of (quinazolin-2-yl)methanone derivatives has been explored from 2,1-benzisoxazoles and α-azido ketones. The transformation involves Rh(III)-catalyzed denitrogenation of α-azido ketones, aza-[4 + 2] cycloaddition, ring opening, and dehydration aromatization processes. Notably, the aza-[4 + 2] cycloaddition of an imine rhodium complex intermediate with 2,1-benzisoxazoles is the key to this reaction.

Background and Purpose. Cardiac autonomic dysfunction is associated with risk of restenosis and cardiovascular mortality in patients after percutaneous transluminal coronary angioplasty (PTCA). Analysis of heart rate variability (HRV) is an important, widely used method for assessing cardiac autonomic regulation. The purpose of this study was to investigate the effect of exercise training on HRV in subjects after PTCA. Subjects and Methods. A total of 84 subjects who had undergone PTCA were recruited for this study. The subjects (age [mean ± SD]=57.0 ± 9.3 years) were randomly assigned to either an exercise group to undergo an 8-week outpatient exercise program or a control group to undergo usual care. Heart rate variability was measured for 5 minutes in the supine resting position at baseline and at the end of 8 weeks. Results. The parasympathetically modulated HRV of the subjects in the exercise group increased significantly compared with the HRV of subjects in the control group. The effects of training on HRV were independent of angioplasty type (balloon or stent) and were unrelated to whether the subjects had received previous PTCA. Discussion and Conclusion. Exercise training can increase parasympathetic modulation of cardiac function in people after they have undergone successful PTCA. Our results suggest that analysis of HRV can be extended to assess the effect of exercise training on cardiac autonomic dysfunction in people after coronary angioplasty. [Tsai MW, Chie WC, Kuo TBJ, et al. Effects of exercise training on heart rate variability after coronary angioplasty. Phys Ther. 2006;86:626-635.] Key Words: Exercise training, Heart rate variability, Percutaneous transluminal coronary angioplasty., Autonomic dysfunction plays a major role in the pathophysiology of ischemic heart disease. (1) Analysis of beat-to-beat heart rate variability (HRV) provides a simple, reproducible, and noninvasive method for quantitatively [...]

Given ever-increasing temperatures, household air conditioner (AC) usage is increasing rapidly, posing significant sustainability challenges. Identifying the drivers of residential demand is critical, especially in developing countries such as China. In contrast to assumptions made by the existing literature, intergenerational parenting and multigenerational households are widespread in China. To address this oversight, this study is the first to use data from an appliance-level, 15-min AC operation database from southern China to quantify the impact of intergenerational parenting families on cooling-related electricity consumption and examine its mechanisms. First, intergenerational parenting significantly positively impacts such consumption. Compared to working-age households, Intergenerational households consume 49% more electricity for cooling, and families with children consume 28% more. In contrast, families with older adults but no children use 6% less electricity for cooling than working-age families. Second, intergenerational families use the AC for 0.5 additional hours per day, set the temperature 0.9°C lower, and keep the AC idle longer than working-age households. Third, intergenerational parenting’s impact shows an M-shaped pattern throughout the day (peaking at 9:00 and 17:00). Fourth, working-age adults significantly moderate the impact of intergenerational parenting on electricity demand.

To study the distribution characteristics and similarity laws of nuclei under different pressures, based on the self-designed decompression chamber and the acoustic measuring system, the size distributions of nuclei in the degassed tap water under negative ambient pressures were measured. A number density distribution function of nuclei based on the modified Weibull distribution function was proposed and verified by the experimental measurement results and some published data of nuclei size distribution. Based on this nuclei number density distribution function, the similarity law of the nuclei size distribution was analyzed: in the scale experiment, the value of exponential in the similarity law of the nuclei number density should be determined by the nuclei size distribution of the water in the prototype experiment and the actual nuclei size distribution of the water in the model experiment. And a precondition is that the nuclei size distributions are similar.

The exercise of quantifying the energy consumption data assembled through household surveys, either by the recall-based approach or the meter-based approach, remains a challenging task, especially in rural areas of developing countries. In this article, we propose a device-based bottom-up accounting method for estimating household energy consumption. This method provides microlevel disaggregated estimates at the intensive margin and documents other difficult-to-measure energy consumption such as biomass at the extensive margin. Even though measurement errors of the household survey might still exist, the structured questionnaire of daily routine behavior questions should greatly alleviate the problem. The new method supplements the existing household energy statistical system, improves its flexibility, and is particularly applicable in developing countries and/or rural areas. We apply the method to a Chinese rural household survey and discuss its differences and similarities with the conventional methods.

A series of zinc complexes, [LXZnEt](1–5) and [LXZn2(OAc)3] (6–9), associated with NNO‐tridentate Schiff base ligands (2‐(((2‐((cyclohexyl[methyl]amino)methyl)phenyl)imino)methyl)phenolate (CAP) derivatives), were synthesized, and their activity toward ring‐opening polymerization (ROP) of L‐lactide (LA) and the reaction of CO2with cyclohexene oxide were also investigated. All of [LXZnEt]revealed excellent catalytic activity to ring‐opening polymerization (ROP) of LA in the presence of benzyl alcohol. Among them, [LHZnEt] (1)showed the highest activity with 82% conversation within 45 s. In contrast, [LXZn2(OAc)3] (6–9)were inactive in ROP of L‐lactide. In addition, all of these Zn complexes demonstrated moderate activity in the reaction of CO2with cyclohexene oxide in the presence of Bu4NCl. A series of Zn complexes associated Schiff base ligands were synthesized, and their applications in L‐lactide polymerization and the reaction of CO2with cyclohexene oxide were studied. Ethyl Zn complexes with electron donation group or steric bulky group on the phenyl ring revealed the low catalytic activity in L‐lactide polymerization..

The spectrum and evolution of proliferation rates in stage IV lung carcinoids is poorly defined. In particular, there are limited data on the prevalence and characteristics of tumors exceeding the standard upper proliferative criteria—as defined largely based on early-stage carcinoids—in metastatic setting. Sixty-six patients with stage IV lung carcinoids were identified, and all evaluable samples (n= 132; mean 2 samples per patient) were analyzed for mitotic counts and Ki-67 rate. Clinicopathologic and genomic features associated with elevated proliferation rates (>10 mitoses per 2 mm2and/or >20% hot-spot Ki-67), and evolution of proliferation rates in serial specimens were analyzed. We found that mitoses and/or Ki-67 exceeded the standard criteria in 35 of 132 (27%) samples, primarily (31/35 cases) at  metastatic sites. Although neuroendocrine neoplasms with >10 mitoses per 2 mm2are currently regarded as de facto neuroendocrine carcinomas, the notion that these cases are part of the spectrum of carcinoids was supported by (1) well-differentiated morphology, (2) conventional proliferation rates in other samples from same patient, (3) genetic characteristics, including the lack of RB1/TP53alterations in all tested samples (n= 19), and (4) median overall survival of 2.7 years, compared to <1 year survival of stage IV neuroendocrine carcinomas in the historic cohorts. In patients with matched primary/metastatic specimens (48 pairs), escalation of mitoses or Ki-67 by ≥10 points was observed in 35% of metastatic samples; clonal relationship in one pair with marked proliferative progression was confirmed by next-generation sequencing. Notably, escalation of proliferation rate was documented in a subset of metastases arising from resected typical carcinoids, emphasizing that the diagnosis of typical carcinoid in primary tumor does not assure low proliferation rate at metastatic sites. In conclusion, stage IV lung carcinoids frequently exceed the standard proliferative criteria established for primary tumors, and commonly exhibit proliferative escalation at metastatic sites. Despite the overlap of proliferation rates, these tumors show fundamental morphologic, genomic and clinical differences from neuroendocrine carcinomas, and should be classified separately from those tumors. Awareness of the increased proliferative spectrum in metastatic carcinoids is critical for their accurate diagnosis. Further studies are warranted to explore the impact of proliferation indices on prognosis and therapeutic responses of patients with metastatic carcinoids.

The energy efficiency of heating systems has become a critical concern for academic study and public welfare worldwide. Developing a comparable measurement tool among various residential space heating systems can offer policy-makers a benchmark for monitoring efficiency, guide them in setting appropriate energy conservation goals and promote overall efficiency improvements through heating system transitions. In the present study, we establish a framework to accommodate heterogenetic space heating systems and model the energy efficiency for performance assessment. By taking the heating area and heating hours into account, two energy intensity indicators are developed. Data from the Chinese Residential Energy Consumption Survey (CRECS) is used to examine the energy intensity for Northern and Southern residences. Our results show opposite findings from other studies, and the interpretation is presented.

To provide a more comprehensive reconstruction of China’s energy consumption, this paper built a machine-learning-based geospatial model that shows great accuracy in recovering historical biomass consumption data using the household survey dataset for China, combined with province-level characteristics and spatiotemporal information. Our study suggested that 6.9 ± 2.6 giga-tons of coal equivalent of biomass were uncounted in China’s statistics, representing 15.9 ± 6.0 percent for China and 2.5 ± 0.9 percent for global final energy consumption. This new estimate significantly reshaped our understanding of China’s energy composition, sectoral mix, indoor air pollutants, and the factors driving energy consumption. These findings provide a replicable template for developing countries hoping to uncover the biomass demand to better design public policy to achieve Sustainable Development Goals.JEL Classification:Q41, Q53, R12, C81, O13

A newly truncated micro-cone array film as light extraction layer for organic light emitting diodes (OLEDs) has been developed, which was fabricated by process combined with photolithography, polydimethylsiloxane (PDMS) molding, self-assembled anti-adhesion, and ultraviolet (UV) forming techniques. In this study, by varying the sidewall angle and fill factor of this film, their influences on the optical properties and light extraction efficiency for OLED are fully investigated. As a result, device performance of OLED employed truncated micro-cone array film, with a high fill factor and sidewall angle of 76.49⁰, was found to be significantly enhanced up to 52% compared with the reference OLED. Notably, the proposed truncated micro-cone array film also stabilized emissive color stability while the viewing angle changes from 0° to 70°, achieving an excellent angular shift with CIE-indices of (0.0025, 0.0066). Aforementioned findings contribute to the development in advanced OLEDs for display and lighting applications.

Objective: To describe growth before and after menarche. Design: Nine hundred five fourth grade school girls were identified as a closed cohort from the first semester of 1993 for the observational study of the onset of menarche and its predictive factors. Settings: Eight elementary schools in Taipei City and Taipei County, Taiwan. Main Outcome Measures: Data were collected from self-administered questionnaires and school records. Height and weight were measured in September, January, February, and June, or only in September and February of each year. Results: All subjects remained in the cohort until sixth grade, 410 of whom had their first menstruation before graduating from elementary school. Height, weight, and body mass index (calculated as weight in kilograms divided by the square of height in meters) at each time point were plotted against 2 time scales: chronological age and time from the onset of menarche. Growth velocity of height and weight across the onset of menarche was assessed with slope change using the mixed-effect model analysis. Conclusions: The results support the hypothesis that height velocity reaches a peak 1 year before menarche but height velocity stopped increasing within 1 year after menarche. The change in weight velocity reveals no obvious growth spurt at age of menarcheal onset. Arch Pediatr Adolesc Med. 2000;154:880-884

Proper clinical transfers of patient care (known as handovers) are important to patient safety. The aim of this study was to investigate the efficacy and satisfaction of an electronic system for clinical transfers of patients with complex surgical procedures. The design was a single-center observational study auditing the handover process. The electronic handover system combined with an electronic health record system was developed to help verbal handover. The system has a checklist to guide the structured handover process and provided information from the health record system. With the system, the elapsed time for surgical handover decreased from 10.5 to 5.4 minutes. The questionnaire analysis showed that clinician satisfaction with surgical handover increased from 69.4% to 79.3%, and the perception of communication completeness increased from 67.2% to 81.6%. The electronic handover system improved communication for the transfer of care for surgical patients.

AbstractTaiwanese artist Chen Chieh-Jen’s video works directly address Taiwan’s post-martial law condition. His video installations demonstrate what I propose to identify as ‘the aesthetics of the multitude’. Through the process of filmmaking, Chen imagines the possibility of a collective political alliance. Theorized by Michael Hardt and Antonio Negri, the multitude rejects reductive identity politics and acts against capitalism. The multitude depicted in Chen’s work suggests a democratic potential that has the capacity to resist the sustained exploitation and homogenization that exists under neo-liberal globalization. His first video installation, Lingchi: Echoes of a Historical Photograph (2002), not only sets the tone for his later works but also signals a paradigm shift in Taiwanese contemporary art from the national to the global after 2000. I argue that Chen’s aesthetics of the multitude move beyond the contentious issue of national identity that characterizes Taiwan’s postcolonial art in the 1990s and anticipates the formation of a postnational subjectivity.

We developed a 5.5 inch real HD AMOLED smartphone with IGZO backplane. The a‐IGZO TFT with Etching Stop Layer (ESL) structure was fabricated at Gen 6 glass substrate. The aIGZO shows its superiority in low cost and low leakage current. The high reliability of a‐IGZO TFT was demonstrated. The optical and electrical characteristics of OLED cell are also shown.

Plasma decompositions of n-butanol (n-b) in air over working gases of air (n-b/air with 21 vol.% O2) and Ar (nb/ air/Ar with 5 vol.% O2) were studied using an atmospheric-pressure plasma jet (APPJ) reactor with and without Pt/Al2O3catalyst. The utilization of catalytic APPJ (CAPPJ) shows excellent performance in terms of the conversion of n-butanol in n-b/air of 94.7% and n-b/air/Ar of 99.5% at plasma energy density = 3.75 kJ L-1and space velocity = 17,400 h-1. By comparing the working gases of air and Ar, the results indicate that n-b/air/Ar system exhibits slightly better performance than n-b/air system in APPJ and CAPPJ, suggesting that energetic primary electrons from Ar discharge would sufficiently retain the plasma reactive species for facilitating the decomposition of n-butanol. The proposed kinetic models show good agreement with the experimental data of APPJ and CAPPJ. The information obtained is useful for the operation, design and analysis of plasma system.

Background Because guanine-based herpes simplex virus thymidine kinase inhibitors are not orally available, we synthesized various 6-deoxy prodrugs of these compounds and evaluated them with regard to solubility in water, oral bioavailability, and efficacy to prevent herpes simplex virus-1 reactivation from latency in a mouse model.Methods Organic synthesis was used to prepare compounds, High Performance Liquid Chromatography (HPLC) to analyze hydrolytic conversion, Mass Spectrometry (MS) to measure oral bioavailability, and mouse latent infection and induced reactivation to evaluate the efficacy of a specific prodrug.Results Aqueous solubilities of prodrugs were improved, oxidation of prodrugs by animal cytosols occurred in vitro, and oral absorption of the optimal prodrug sacrovir™ (6-deoxy-mCF3PG) in the presence of the aqueous adjuvant Soluplus® and conversion to active compound N2-[3-(trifluoromethyl)pheny])guanine (mCF3PG) were accomplished in mice. Treatment of herpes simplex virus-1 latent mice with sacrovir™ in 1% Soluplus in drinking water significantly suppressed herpes simplex virus-1 reactivation and viral genomic replication.Conclusions Ad libitum oral delivery of sacrovir™ was effective in suppressing herpes simplex virus-1 reactivation in ocularly infected latent mice as measured by the numbers of mice shedding infectious virus at the ocular surface, numbers of trigeminal ganglia positive for infectious virus, number of corneas that had detectable infectious virus, and herpes simplex virus-1 genome copy numbers in trigeminal ganglia following reactivation. These results demonstrate the statistically significant effect of the prodrug on suppressing herpes simplex virus-1 reactivation in vivo.

Inequality is a growing public concern and economic threat. The degree of which, however, varies greatly depending on the choice of indicators for measurement. In this paper, we compare the strength and weaknesses of the existing indicators such as income and wealth and propose a new measure of inequality based on household electricity consumption. We believe that our measure has the advantage of capturing both service flows and stock values of durables, embodying both the outcome and opportunity inequality, and confronting fewer measurement issues. The new inequality measure based on electricity consumption may complement the existing ones by providing a relatively complete and well-balanced picture of the overall welfare inequality.

The slot coating process in the production of polymer films has a wide range of applications. However, the process cannot be systemized. This study used the computational fluid dynamics software Polyflow to analyze the slot coating process and investigate the influence that the process parameters have on the characteristics of thin-film coating to reduce the time and cost consumed in the experimental methods. The rheological characteristics of the non-Newtonian fluid used in this study were first identified by conducting experiments, and then configured in the simulation software for fitting with mathematical models. In addition, the models of the slot coating process were constructed, and the Arbitrary Lagrangian-Eulerian (ALE) calculation methods were then used in the Polyflow software. The simulation results were then compared to the experimental results and the findings reported in relevant literature, to determine the influence that the process parameters have on the characteristics of thin-film coating. The simulation results were represented graphically in a coating window plot. The comparison results indicate that the viscosity-shear rate characteristic of the material in the shear rate range of optical film coating is an excellent fit for the Cross Law. When the coating speed is too high or the amount of fluid supply is insufficient, phenomena such as break lines, uneven thickness, and air entrainment can occur.

Molecular rotational spectroscopy based on a strong-field-ionization-induced nitrogen laser is employed to investigate the time evolution of the rotational wave packet composed by a coherent superposition of quantum rotational states created in a field-free molecular alignment. We show that this technique uniquely allows real-time observation of the ultrafast dynamics of the molecular rotational wave packet. Our analysis also shows that there exist two channels of generation of the nitrogen laser, shedding light on the population inversion mechanism behind the air laser generated by intense femtosecond laser pulses. [ABSTRACT FROM AUTHOR]

This study was aimed to investigate dynamic characteristics of a milling machine with horizontal spindle tooling system, which was feed through the linear feeding mechanism combined with the sliding guides and linear roller guide modulus. To predict the dynamic characteristics, we created finite element model of the milling machine with the introduction of the contact stiffness defined at the sliding and rolling interface, respectively. The results of the finite element simulations reveal that linear guides with different preloads greatly affect the dynamic responses of the horizontal spindle tool. The maximum dynamic compliance can be increased by 7.4 % in X-axis direction and increased by 12 % in Y-axis direction, respectively when the linear guides are changed from low to high preload. Overall, current results clearly illustrate that the proposed modeling approach of feeding mechanism can quantify the preload effect of the guideway system on the dynamic performance of a milling machine.

HD Radio standard can realize the smooth transition from analog to digital using "in-band on-channel (IBOC)" technology, which is the most advantageous choice for analog broadcasting digitized. In HD Radio Hybrid and Extended waveform type, the digital signal employs the same carrier with the analog signal, and is transmitted on both sides of the analog FM signal. Since the digital carrier adjacent analog signal, the core to implement IBOC is the interference problem of digital signal to analog signal at the beginning of broadcasting digitized. For the interference evaluation model, this paper apply noise masking ratio (NMR) and objective evaluation level (ODG) as a combined evaluation factor for digital-analog interference in IBOC broadcasting. This interference evaluation method which utilizes the comprehensive advantages of NMR and ODG, with more scientific than the SNR measurements, can be widely used as an evaluation index for audio interference.

The objectives of this study were to develop and validate an instrument for the measurement of health-related quality of life (HRQoL) based on view of Traditional Chinese Medicine (TCM).

In this paper, a time-domain analysis method based on probability density estimation is presented for rotating machine fault detection. Generally, the vibration signals obtained from a rotating machine are time-variant since they are strongly related to the rotational speed that is not constant even in the macro steady state. Since the mostly used signal processing method, the Fourier analysis is only suitable for stationary signals, the development of the joint time-frequency analysis is demanded. Here, the probability density estimation method based on Parzen window is introduced. The probability density function of the vibration signal of the rotating machine is estimated by Parzen window, and a threshold value is predefined to decide the state of the rotating machine. By inspecting the change of the probability density of the vibration signal, the condition of the machine is monitored. Air gap eccentricity and ball cage broken bearing are considered in the experiment section, they are difficult to be detected in frequency domain while the rotating speed is not constant. The validity of the method is proved by the experiment.

We report on the generation of an intense extreme-ultraviolet (EUV) supercontinuum with photon energies spanning from 35 to 50 eV (i.e., supporting an isolated attosecond pulse with a duration of ∼271 as) by loosely focusing 35 fs, 11 mj pulses from a femtosecond laser amplifier into a 10-mm-long gas cell filled with krypton gas. The dramatic change in spectral and temporal properties of the driver pulses after passing through the gas cell indicates that propagation effects play a significant role in promoting the generation of the EUV supercontinuum. [ABSTRACT FROM AUTHOR]

We present experimental and theoretical evidence on the breakdown of the simple man's model in the high-energy recollision region by examining both the energy-resolved angular distribution of photoelectrons in above-threshold ionization and the spectrum of high-order harmonics generated in elliptically polarized driver fields. With the help of a semiclassical model calculation, we show that, surprisingly, even for the high-energy recollision electrons, their wave-packet dynamics can be influenced strongly by the Coulomb field. [ABSTRACT FROM AUTHOR]

We demonstrate that the peak intensity in the filament core, which is inherently limited by the intensity clamping effect during femtosecond laser filamentation, can be significantly enhanced using spatiotemporally focused femtosecond laser pulses. In addition, the filament length obtained by spatiotemporally focused femtosecond laser pulses is ~25 times shorter than that obtained by a conventional focusing scheme, resulting in improved high spatial resolution. [ABSTRACT FROM AUTHOR]

A mathematical model for the output waveform of SPWM VSI (voltage source inverter) is created specific to the harmonic problem of SPWM voltage source inverter. Through theoretical analysis and calculation, we can get the distribution regularity of the output harmonic wave in the process of frequency conversion and voltage transformation. Utilizing the matlab to verify the simulation, we can get such results like “frequency conversion will lead to the shift of the harmonic wave’s distribution center”, “voltage transformation will cause the valuable change of the harmonic wave and the valuable change direction of harmonic wave is opposite to that of the fundamental wave”. All of these will have significant guide meaning to the application of SPWM.

Based on the finding that aerobic Gram-positive antibacterials that inhibit DNA polymerase IIIC (pol IIIC) were potent inhibitors of the growth of anaerobic Clostridium difficile (CD) strains, we chose to clone and express the gene for pol IIIC from this organism. The properties of the recombinant enzyme are similar to those of related pol IIICs from Gram-positive aerobes, e.g. B. subtilis. Inhibitors of the CD enzyme also inhibited B. subtilis pol IIIC, and were competitive with respect to the cognate substrate 2-deoxyguanosine 5-triphosphate (dGTP). Significantly, several of these inhibitors of the CD pol IIIC had potent activity against the growth of CD clinical isolates in culture.

Winner by aggregate: Incorporating an anion‐binding squaramide group into a polymeric architecture results in drastic alterations in the selectivity and magnitude of its anion‐induced response, resulting in a sensitive and discriminating turn‐on fluorescence sensor for dihydrogenphosphate ions. This unusual behavior is the result of a cooperative, anion‐triggered aggregation process (see picture; scale bar: 1 μm).

The multifunction evaluation system for coal-bed gas adsorption isothermal and pollution of drilling fluids is used for detecting the isothermal curves of adsorption and desorption needed in coal-bed gas exploration and development, at the same time, the system is used for studying the influences of external conditions applied on the coal bed such as reservoir temperature, moisture in the coal, the component of adsorbed gas, the drilling fluids and fracturing fluids on the coal beds, and pertaining to the technical area of the test instruments of coal-bed gas for drilling, exploration and development. Structure of the system is rational with advanced performance and high automation, its pressure and temperature are controlled by high precision sensors, and the microcomputer matched with the instrument has functions of rapid data acquisition, data process and chart plotting. This evaluation system can not only be used for detecting the isothermal curves of adsorption and desorption of single component gases, also can be used for detecting the isothermal curves of multi-component gases and deriving the diffusion coefficient of gas in the coal beds. Also the system can be used for evaluating the restoration value of the coal-bed desorption ability both before and after being polluted by drilling fluids and estimating the influence of drilling fluid and fracturing fluid, by which the shortcomings of unicity of adsorption and desorption test of coal bed gas, low automation level and low accuracy at present are eliminated, and it has the characteristics of clear flow-sheet, easy operation, modules of experiment software and standardization of experiment data.

ABSTRACTThe incidence of and risk factors for acquiring community-associated methicillin-resistant Staphylococcus aureus(CA-MRSA) among patients staying in intensive care units (ICUs) remain unclear. We enrolled patients staying in two ICUs at the Far Eastern Memorial Hospital during the period of 1 September 2008 to 30 September 2009 to clarify this issue. Surveillance cultures for MRSA were taken from nostril, sputum or throat, axillae, and the inguinal area in all enrolled patients upon admission to the ICU, every 3 days thereafter, and on the day of discharge from the ICU. For each MRSA isolate, we performed multilocus sequence typing, identified the type of staphylococcal cassette chromosome mec, detected the presence of the Panton-Valentine leukocidin gene, and conducted drug susceptibility tests. Among the 1,906 patients who were screened, 203 patients were carriers of MRSA before their admission to the ICU; 81 patients acquired MRSA during their stay in the ICU, including 31 who acquired CA-MRSA. The incidence rates of newly acquired MRSA and CA-MRSA during the ICU stay were 7.9 and 3.0 per 1,000 patient-days, respectively. Prior usage of antipseudomonal penicillins and antifungals and the presence of a nasogastric tube were found to be independent risk factors for acquiring CA-MRSA during the ICU stay when data for CA-MRSA carriers and patients without carriage of MRSA were compared (P= 0.0035, 0.0330, and 0.0262, respectively). Prior usage of carbapenems was found to be a protective factor against acquiring CA-MRSA when data for patients with CA-MRSA and those with health care-associated MRSA acquired during ICU stay were compared (P= 0.0240).

Community-associated methicillin-resistant Staphylococcus aureus(MRSA) has become an important pathogen in community and nosocomial infections. The impact of these emerging MRSA strains on mortality in adult patients with community-onset S aureusbacteremia remains uncertain. We defined community strain MRSA (CoSt-MRSA) and hospital strain MRSA (HoSt-MRSA) according to the results of staphylococcus cassette chromosome mec (SCCmec) molecular typing CoSt-MRSA isolates had SCCmec type IV or V genes, and HoSt-MRSA isolates had SCCmec type I, II, or III genes. We quantitatively evaluated the impact of the MRSA strain on mortality in patients with CoSt-MRSA or HoSt-MRSA bacteremia by comparison with mortality in patients with methicillin-susceptible S aureus(MSSA) bacteremia.

ABSTRACTIn order to determine the prevalence of methicillin (meticillin)-resistant Staphylococcus aureus(MRSA) colonization among adults in community settings in Taiwan and identify its risk factors, we conducted the present study. For a 3-month period, we enrolled all adults who attended mandatory health examinations at three medical centers and signed the informed consent. Nasal swabs were taken for the isolation of S. aureus. For each MRSA isolate, we performed multilocus sequence typing, identification of the staphylococcal cassette chromosome mec, tests for the presence of the Panton-Valentine leukocidin gene, and tests for drug susceptibilities. Risk factors for MRSA colonization were determined. The results indicated that the MRSA colonization rate among adults in the community settings in Taiwan was 3.8% (119/3,098). Most MRSA isolates belonged to sequence type 59 (84.0%). Independent risk factors for MRSA colonization included the presence of household members less than 7 years old (P< 0.0001) and the use of antibiotics within the past year (P= 0.0031). Smoking appeared to be protective against MRSA colonization (P< 0.0001).

The neuroprotective effect of schizandrin on the glutamate (Glu)-induced neuronal excitotoxicity and its potential mechanisms were investigated using primary cultures of rat cortical cells. After exposure of primary cultures of rat cortical cells to 10 μM Glu for 24 h, cortical cell cultures exhibited remarkable apoptotic death. Pretreatment of the cortical cell cultures with schizandrin (10, 100 μM) for 2 h significantly protected cortical neurons against Glu-induced excitotoxicity. The neuroprotective activity of schizandrin was the most potent at the concentration of 100 μM. Schizandrin reduced apoptotic characteristics by DAPI staining in Glu-injured cortical cell cultures. In addition, schizandrin diminished the intracellular Ca2+influx, inhibited the subsequent overproduction of nitric oxide (NO), reactive oxygen species (ROS), and cytochrome c, and preserved the mitochondrial membrane potential. Furthermore, schizandrin also increased the cellular level of glutathione (GSH) and inhibited the membrane lipid peroxidation malondialdehyde (MDA). As indicated by Western blotting, schizandrin attenuated the protein level changes of procaspase-9, caspase-9, and caspase-3 and cleaved poly(ADP-ribose) polymerase (PARP). Taken together, these results suggest that schizandrin protected primary cultures of rat cortical cells against Glu-induced apoptosis through a mitochondria-mediated pathway and oxidative stress.

New cobalt‐containing secondary phosphine oxides [(μ‐PPh2CH2PPh2)Co2(CO)4{μ,η‐PhCCP(O)(H)(R)}] (8 a: R=tBu; 8 b: R=Ph) were prepared by reaction of secondary phosphine oxides PhCCP‐ (O)(H)(R) (6 a: R=tBu; 6 b: R=Ph) with dppm‐bridged dicobalt complex [(μ‐PPh2CH2PPh2)Co2(CO)6] (2). The molecular structures of 8 aand 8 bwere determined by single‐crystal X‐ray diffraction. Although palladium‐catalyzed Heck reactions employing 8 bas ligand gave satisfying results, 8 aperformed poorly in the same reaction. Judging from these results, a tautomeric equilibrium between 8 band its isomeric form [(μ‐PPh2CH2PPh2)Co2(CO)4{μ,η‐PhCCP(OH)(Ph)}] 8 b′indeed takes place, but it is unlikely between 8 aand [(μ‐PPh2CH2PPh2)Co2(CO)4{μ,η‐PhCCP(OH)(tBu)}] (8 a′). The DFT studies demonstrated that reasonable activation energies for the tautomeric conversions can be achieved only via a bimolecular pathway. Since a tBu group is much larger than a Ph group, the conversion is presumably only feasible in the case of 8 b⇌8 b′, but not in the case of 8 a⇌8 a′. Another cobalt‐containing phosphine, namely, [(μ‐PPh2CH2PPh2)Co2(CO)4{μ,η‐PhCCP(NEt2)(tBu)}] (7 a), and its oxidation product [(μ‐PPh2CH2PPh2)Co2(CO)4{μ,η‐PhCCP(O)(NEt2)(tBu)}] 7 a′were prepared from the reaction of PhCCP(NEt2)(tBu) (5 a) with 2. The molecular structures of 7 aand 7 a′were determined by single‐crystal X‐ray diffraction. The phosphorus atom is surrounded by substituents in a tetrahedral environment. A PN single bond (1.676(3) Å) is observed in the molecular structure of 7 a. Heck reactions employing 7 a/Pd(OAc)2as catalyst system exhibited efficiency comparable to that of 8 a/Pd(OAc)2.

Novel Gram-positive (Gram+) antibacterial compounds consisting of a DNA polymerase IIIC (pol IIIC) inhibitor covalently connected to a topoisomerase/gyrase inhibitor are described. Specifically, 3-substituted 6-(3-ethyl-4-methylanilino)uracils (EMAUs) in which the 3-substituent is a fluoroquinolone moiety (FQ) connected by various linkers were synthesized. The resulting “Fr−FQ” hybrid compounds were significantly more potent than the parent EMAU compounds as inhibitors of pol IIIC and were up to 64-fold more potent as antibacterials in vitro against Gram+ bacteria. The hybrids inhibited the FQ targets, topoisomerase IV and gyrase, with potencies similar to norfloxacin but 10-fold lower than newer agents, for example, ciprofloxacin and sparfloxacin. Representative hybrids protected mice from lethal Staphylococcus aureus infection after intravenous dosing, and one compound showed protective effect against several antibiotic-sensitive and -resistant Gram+ infections in mice. The AU−FQ hybrids are a promising new family of antibacterials for treatment of antibiotic-resistant Gram+ infections.

A copper(II)-promoted denitrogenation/oxidation reaction for the preparation of primary α-ketoamides was developed using α-azido ketones as a substrate and TEMPO as an oxidant. α-Azido ketones were denitrogenated in situ to form an imino ketone intermediate, which underwent a radical addition process and radical migration to form α-ketoamides. It is worth noting that the imino ketone intermediate is the key to this reaction.

China’s efforts to encourage energy transition from coal to cleaner methods of space heating have gained great achievement. However, not all progress met expectations; that is, some households still rely on solid fuel. Sociocultural factors provide one plausible explanation. While existing studies have examined and quantified the socioeconomic factors, little attention has been paid to the peer effects that are often critical in the Chinese cultural context. This study first presents household energy consumption patterns using household-level data on the coal-switching program in rural Beijing. It shows that the coal-switching program did not completely eliminate the use of solid fuel for space heating as expected. To explore the underlying determinants, we apply an econometric model of the forces driving energy transition, focusing on peer effects. The results confirm that the coal-switching program significantly reduces the use of solid fuel. Moreover, it reveals that the peer effect, measured by the average village-level solid fuel use rate, matters for households’ fuel choices. We also find that the peer effect varies with different income levels and policies. These findings provide new evidence and insights for future policy design.

The easily synthesized B, B-dihaloalkylboranes, in the presence of either Et 3N or i-Pr 2NEt, converts ethyl ketones, RCOEt, to 96- ≥ 99% Z-enolates, converted by aldehydes to essentially pure syn-aldols.

Treatment of the diisopinocampheylborinates of a representative series of methyl ketones with a representative series of aldehydes, both of differing steric requirements provides aldols whose enantiomeric purities depend on the steric requirements of both the ketones and the aldehydes. This study has shown that increasing the steric requirements of the R group in the ketones has a pernicious effect on the ee, while increasing the steric requirements of the R group in the aldehydes exerts a beneficial effect on the ee.

In this paper, a two-level decomposition method for design optimization is proposed which is an extension of the model coordination methods. The method couples the global monotonicity analysis of the first-level subproblem(s) with an optimization method (single-level method) or the second-level problem. Three classes of problems are considered where in the first-level they have: (1) one subproblem with one local variable, (2) several subproblems with one local variable, and (3) several subproblems with several local variables. Some test results have been presented which shows the improved performance of the proposed approach over a conventional single-level optimization method.

One hundred and seventy four (81% of all) pathologically confirmed new incident cases of female breast cancer identified from a medical center in Taipei from February, 1993 to June, 1994 were selected as the case group. Four hundred and fifty three inpatient controls who were without obstetric-gynecological, breast, or malignant diseases were individually matched for each case by age and date of admission. Information was obtained through direct interview and review of medical records. Conditional logistic regression was used to estimate the effects of each risk factor. After adjusting for education level, body mass index, age at menarche and first full-term pregnancy, parity, menopausal status and age at menopause, lifetime lactation, use of lactation inhibition hormones, and family history of breast cancer, breast cancer risk significantly elevated in use of OC before 25 years old and before 1971. In stratified analysis, significantly higher risk were found in OC use before 25 years old and in duration of use less than one year among post-menopausal subjects. Our results support the notion that OC use in early life for younger women and in early calendar years increase breast cancer risk. Int. J. Cancer 77:219–223, 1998.© 1998 Wiley-Liss, Inc.