The fast and accurate analysis of chiral chemical mixtures is crucial for many applications but remains challenging. Here we use elliptically-polarized femtosecond laser pulses at high repetition ...rates to photoionize chiral molecules. The 3D photoelectron angular distribution produced provides molecular fingerprints, showing a strong forward-backward asymmetry which depends sensitively on the molecular structure and degree of ellipticity. Continuously scanning the laser ellipticity and analyzing the evolution of the rich, multi-dimensional molecular signatures allows us to observe real-time changes in the chemical and chiral content present with unprecedented speed and accuracy. We measure the enantiomeric excess of a compound with an accuracy of 0.4% in 10 min acquisition time, and follow the evolution of a mixture with an accuracy of 5% with a temporal resolution of 3 s. This method is even able to distinguish isomers, which cannot be easily distinguished by mass-spectrometry.
Catalysis by gold Bond, G. C. (Geoffrey Colin); Louis, Catherine; Thompson, David T
2006, 2006., 2006-08-15, Volume:
6
eBook, Book
Gold has traditionally been regarded as inactive as a catalytic metal. However, the advent of nanoparticulate gold on high surface area oxide supports has demonstrated its high catalytic activity in ...many chemical reactions. Gold is active as a heterogeneous catalyst in both gas and liquid phases, and complexes catalyse reactions homogeneously in solution. Many of the reactions being studied will lead to new application areas for catalysis by gold in pollution control, chemical processing, sensors and fuel cell technology. This book describes the properties of gold, the methods for preparing gold catalysts and ways to characterise and use them effectively in reactions. The reaction mechanisms and reasons for the high activities are discussed and the applications for gold catalysis considered.
The monitoring of adverse drug reactions (ADRs) through pharmacovigilance is vital to patient safety. Spontaneous reporting of ADRs is one method of pharmacovigilance, and in the UK this is ...undertaken through the Yellow Card Scheme (YCS). Yellow Card reports are submitted to the Medicines and Healthcare products Regulatory Agency (MHRA) by post, telephone or via the internet. The MHRA electronically records and reviews information submitted so that important safety issues can be detected. While previous studies have shown differences between patient and health-care professional (HCP) reports for the types of drugs and reactions reported, relatively little is known about the pharmacovigilance impact of patient reports. There have also been few studies on the views and experiences of patients/consumers on the reporting of suspected ADRs.
To evaluate the pharmacovigilance impact of patient reporting of ADRs by analysing reports of suspected ADRs from the UK YCS and comparing reports from patients and HCPs. To elicit the views and experiences of patients and the public about patient reporting of ADRs.
(1) Literature review and survey of international experiences of consumer reporting of ADRs; (2) descriptive analysis of Yellow Card reports; (3) signal generation analysis of Yellow Card reports; (4) qualitative analysis of Yellow Card reports; (5) questionnaire survey of patients reporting on Yellow Cards; (6) qualitative analysis of telephone interviews with patient reporters to the scheme; (7) qualitative analysis of focus groups and usability testing of the patient YCS; and (8) national omnibus telephone survey of public awareness of the YCS.
Patients (n = 5180) and HCPs (n = 20,949) submitting Yellow Card reports from October 2005 to September 2007. Respondents to questionnaire survey (n = 1362). Participants at focus groups and usability testing sessions (n = 40). National omnibus telephone survey (n = 2028).
The literature review included studies in English from across the world. All other components included populations from the UK; the omnibus survey was restricted to Great Britain.
None.
Characteristics of patient reports: types of drug and suspected ADR reported; seriousness of reports; and content of reports. The relative contributions of patient reports and of HCP reports to signal generation. Views and experiences of patient reporters. Views of members of the public about the YCS, including user-friendliness and usability of different ways of patient reporting. Public awareness of the YCS. Suggestions for improving patient reporting to the YCS.
Compared with HCPs, patient reports to the YCS contained a higher median number of suspected ADRs per report, and described reactions in more detail. The proportions of reports categorised as 'serious' were similar; the patterns of drugs and reactions reported differed. Patient reports were richer in their descriptions of reactions than those from HCPs, and more often noted the effects of ADRs on patients' lives. Combining patient and HCP reports generated more potential signals than HCP reports alone; some potential signals in the 'HCP-only' data set were lost when combined with patient reports, but fewer than those gained; the addition of patient reports to HCP reports identified 47 new 'serious' reactions not previously included in 'Summaries of Product Characteristics'. Most patient reporters found it fairly easy to make reports, although improvements to the scheme were suggested, including greater publicity and the redesign of web- and paper-based reporting systems. Among members of the public, 8.5% were aware of the YCS in 2009.
Patient reporting of suspected ADRs has the potential to add value to pharmacovigilance by reporting types of drugs and reactions different from those reported by HCPs; generating new potential signals; and describing suspected ADRs in enough detail to provide useful information on likely causality and impact on patients' lives. These findings suggest that further promotion of patient reporting to the YCS is justified, along with improvements to existing reporting systems. In order of priority, future work should include further investigation of (1) the pharmacovigilance impact of patient reporting in a longer-term study; (2) the optimum approach to signal generation analysis of patient and HCP reports; (3) the burden of ADRs in terms of impact on patients' lives; (4) the knowledge and attitudes of HCPs towards patient reporting of ADRs; (5) the value of using patient reports of ADRs to help other patients and HCPs who are seeking information on patient experiences of ADRs; and (6) the impact of increasing publicity and/or enhancements to reporting systems on the numbers and types of Yellow Card reports from patients.
The National Institute for Health Research Health Technology Assessment programme.
The optical properties of the light-absorbing, carbonaceous substance often called "soot," "black carbon," or "carbon black" have been the subject of some debate. These properties are necessary to ...model how aerosols affect climate, and our review is targeted specifically for that application. We recommend the term
light-absorbing carbon
to avoid conflict with operationally based definitions. Absorptive properties depend on molecular form, particularly the size of sp
2
-bonded clusters. Freshly-generated particles should be represented as aggregates, and their absorption is like that of particles small relative to the wavelength. Previous compendia have yielded a wide range of values for both refractive indices and absorption cross section. The absorptive properties of light-absorbing carbon are not as variable as is commonly believed. Our tabulation suggests a mass-normalized absorption cross section of 7.5 ± 1.2 m
2
/g at 550 nm for uncoated particles. We recommend a narrow range of refractive indices for strongly-absorbing carbon particles, of which the highest is 1.95-0.79i. Our refractive indices are consistent with most measurements reported in the literature, and values used in present-day climate modeling are in error. Realistic refractive indices underpredict measured absorption by about 30% when used with common theories for spherical particles or aggregates. Field programs since about 1970 have measured quantities relevant to light absorption, but have only recently made enough measurements to isolate the light-absorbing carbonaceous component and determine its absorptive properties.
Controlling architecture of electrode composites is of particular importance to optimize both electronic and ionic conduction within the entire electrode and improve the dispersion of active ...particles, thus achieving the best energy delivery from a battery. Electrodes based on conventional binder systems that consist of carbon additives and nonconductive binder polymers suffer from aggregation of particles and poor physical connections, leading to decreased effective electronic and ionic conductivities. Here we developed a three-dimensional (3D) nanostructured hybrid inorganic-gel framework electrode by in situ polymerization of conductive polymer gel onto commercial lithium iron phosphate particles. This framework electrode exhibits greatly improved rate and cyclic performance because the highly conductive and hierarchically porous network of the hybrid gel framework promotes both electronic and ionic transport. In addition, both inorganic and organic components are uniformly distributed within the electrode because the polymer coating prevents active particles from aggregation, enabling full access to each particle. The robust framework further provides mechanical strength to support active electrode materials and improves the long-term electrochemical stability. The multifunctional conductive gel framework can be generalized for other high-capacity inorganic electrode materials to enable high-performance lithium ion batteries.
To determine whether the absence or presence of clinical pharmacists in intensive care units (ICUs) results in differences in mortality rates, length of ICU stay, and ICU charges for Medicare ...patients with nosocomial-acquired infections, community-acquired infections, and sepsis.
The type and level of pharmacy services provided to ICUs were obtained from a 2004 national survey. Clinical pharmacy services were defined as having at least a partial pharmacist full-time equivalent specifically devoted to the ICU for the purpose of direct involvement in patient care. Infections were defined using International Classification of Diseases, Ninth Revision, Clinical Modification codes. ICU outcome data were drawn from the 2004 modified Medicare provider analysis and review. Depending on the infection studied, the involvement of clinical pharmacists was evaluated in 8,927-54,042 patients from 265 to 276 hospitals.
None.
Mortality rates, length of ICU stay, Medicare charges, drug charges, and laboratory charges for each of the infections categorized according to the absence or presence of clinical pharmacists. Compared to ICUs with clinical pharmacists, mortality rates in ICUs that did not have clinical pharmacists were higher by 23.6% (p < 0.001, 386 extra deaths), 16.2% (p = 0.008, 74 extra deaths), and 4.8% (p = 0.008, 211 extra deaths) for nosocomial-acquired infections, community-acquired infections, and sepsis, respectively. Similarly, ICU length of stay was longer by 7.9% (p < 0.001, 14,248 extra days), 5.9% (p = 0.03, 2855 extra days), and 8.1% (p < 0.001, 19,215 extra days) for nosocomial-acquired infections, community-acquired infections, and sepsis, respectively. ICUs that did not have clinical pharmacists had greater total Medicare billings of 12% (p < 0.001, $132,978,807 extra billing charges), 11.9% (p < 0.001, $32,240,378 extra billing charges), and 12.9% (p < 0.001, $224,694,784 extra billing charges) for nosocomial-acquired infections, community-acquired infections, and sepsis, respectively. Similar findings were observed for Medicare drug charges and laboratory charges.
The involvement of clinical pharmacists in the care of critically ill Medicare patients with infections is associated with improved clinical and economic outcomes. Hospitals should consider employing clinical ICU pharmacists.
Extrasolar planet host stars have been found to be enriched in key planet-building elements. These enrichments have the potential to drastically alter the composition of material available for ...terrestrial planet formation. Here, we report on the combination of dynamical models of late-stage terrestrial planet formation within known extrasolar planetary systems with chemical equilibrium models of the composition of solid material within the disk. This allows us to determine the bulk elemental composition of simulated extrasolar terrestrial planets. A wide variety of resulting planetary compositions are found, ranging from those that are essentially 'Earth like', containing metallic Fe and Mg silicates, to those that are dominated by graphite and SiC. This shows that a diverse range of terrestrial planets may exist within extrasolar planetary systems.
Understanding the biogeochemical cycling of mercury is critical for explaining the presence of mercury in remote regions of the world, such as the Arctic and the Himalayas, as well as local ...concentrations. While we have good knowledge of present-day fluxes of mercury to the atmosphere, we have little knowledge of what emission levels were like in the past. Here we develop a trend of anthropogenic emissions of mercury to the atmosphere from 1850 to 2008for which relatively complete data are availableand supplement that trend with an estimate of anthropogenic emissions prior to 1850. Global mercury emissions peaked in 1890 at 2600 Mg yr–1, fell to 700–800 Mg yr–1 in the interwar years, then rose steadily after 1950 to present-day levels of 2000 Mg yr–1. Our estimate for total mercury emissions from human activities over all time is 350 Gg, of which 39% was emitted before 1850 and 61% after 1850. Using an eight-compartment global box-model of mercury biogeochemical cycling, we show that these emission trends successfully reproduce present-day atmospheric enrichment in mercury.
Objective: To determine if hospital‐based clinical pharmacy services and pharmacy staffing continue to be associated with mortality rates.
Methods: A database was constructed from 1998 MedPAR, ...American Hospital Association's Annual Survey of Hospitals, and National Clinical Pharmacy Services databases, consisting of data from 2,836,991 patients in 885 hospitals. Data from hospitals that had 14 clinical pharmacy services were compared with data from hospitals that did not have these services; levels of hospital pharmacist staffing were also compared. A multiple regression analysis, controlling for severity of illness, was used.
Results: Seven clinical pharmacy services were associated with reduced mortality rates: pharmacist‐provided drug use evaluation (4491 reduced deaths, p=0.016), pharmacist‐provided in‐service education (10,660 reduced deaths, p=0.037), pharmacist‐provided adverse drug reaction management (14,518 reduced deaths, p=0.012), pharmacist‐provided drug protocol management (18,401 reduced deaths, p=0.017), pharmacist participation on the cardiopulmonary resuscitation team (12,880 reduced deaths, p=0.009), pharmacist participation on medical rounds (11,093 reduced deaths, p=0.021), and pharmacist‐provided admission drug histories (3988 reduced deaths, p=0.001). Two staffing variables, number of pharmacy administrators/100 occupied beds (p=0.037) and number of clinical pharmacists/100 occupied beds (p=0.023), were also associated with reduced mortality rates.
Conclusion: The number of clinical pharmacy services and staffing variables associated with reduced mortality rates increased from two in 1989 to nine in 1998. The impact of clinical pharmacy on mortality rates mandates consideration of a core set of clinical pharmacy services to be offered in United States hospitals. These results have important implications for health care in general, as well as for our profession and discipline.
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