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In this manuscript, we highlight current literature on environmental hygiene techniques to combat reservoirs of antibiotic resistant organisms in the healthcare environment. We discuss several topics for each strategy, including mechanism of action, assessment of effectiveness based on studies, cost, and real-world translatability. The techniques and topics summarized here are not inclusive of all available environmental hygiene techniques but highlight some of the more popular and investigated strategies. We focus on the following: Ultraviolet radiation, hydrogen peroxide vapor, copper-coated surfaces, phages, interventions involving sinks, and educational initiatives.
To compare the recovery of yeast from hospital surfaces from two different collection methods: Eswab moistened with molecular water, and premoistened stick-mounted sponge.
Design:
Comparison of collection methods for the recovery of yeast in the hospital environment.
Setting:
This study took place at intensive care units of a large academic medical center.
To measure SARS-CoV-2 anti-nucleocapsid (anti-N) antibody seropositivity among healthcare personnel (HCP) without a history of COVID-19 and to identify HCP characteristics associated with seropositivity.
Design:
Prospective cohort study from September 22, 2020, to March 3, 2022.
Setting:
A tertiary care academic medical center.
Participants:
727 HCP without prior positive SARS-CoV-2 PCR testing were enrolled; 559 HCP successfully completed follow-up.
Methods:
At enrollment and follow-up 1–6 months later, HCP underwent SARS-CoV-2 anti-N testing and were surveyed on demographics, employment information, vaccination status, and COVID-19 symptoms and exposures.
Results:
Of 727 HCP enrolled, 27 (3.7%) had a positive SARS-CoV-2 anti-N test at enrollment. Seropositive HCPs were more likely to have a household exposure to COVID-19 in the past 30 days (OR 7.92, 95% CI 2.44–25.73), to have had an illness thought to be COVID-19 (4.31, 1.94–9.57), or to work with COVID-19 patients more than half the time (2.09, 0.94–4.77). Among 559 HCP who followed-up, 52 (9.3%) had a positive SARS-CoV-2 anti-N antibody test result. Seropositivity at follow-up was associated with community/household exposures to COVID-19 within the past 30 days (9.50, 5.02–17.96; 2.90, 1.31–6.44), having an illness thought to be COVID-19 (8.24, 4.44–15.29), and working with COVID-19 patients more than half the time (1.50, 0.80–2.78).
Conclusions:
Among HCP without prior positive SARS-CoV-2 testing, SARS-CoV-2 anti-N seropositivity was comparable to that of the general population and was associated with COVID-19 symptomatology and both occupational and non-occupational exposures to COVID-19.
Background: Status dystonicus (SD) is a life-threatening form of dystonia with limited treatments available. We sought to better understand the processes, outcomes, and complications of deep brain stimulation (DBS) for pediatric SD through a systematic review alongside an institutional case series. Methods: Data regarding treatment, stimulation parameters, dystonia severity and outcomes was collected for the case series (n=7) and systematic review (n=70, conducted in accordance with PRISMA guidelines). This was analysed descriptively (rates, outcome measures). For the case series we created probabilistic voxel-wise maps for improvement in dystonia based on brain region stimulated. Results: All patients in our case series and > 95% of patients in the systematic review had resolution of SD with DBS, typically within 2-4 weeks. Most patients in the review (84%) and all patients in the case series had DBS implanted to the globus pallidus internus. In terms of dystonia severity scores, there was a mean improvement of 25% (case series) or 49% (systematic review). Reported mortality was 4% in the systematic review. Conclusions: DBS for pediatric SD is feasible and safe. It allows for increased survival as well as quality of life - however risks still exist. More work is needed to determine timing, eligibility, and stimulation parameters.
Dental healthcare personnel (DHCP) are at high risk of exposure to coronavirus disease 2019 (COVID-19). We sought to identify how DHCP changed their use of personal protective equipment (PPE) as a result of the COVID-19 pandemic, and to pilot an educational video designed to improve knowledge of proper PPE use.
Design:
The study comprised 2 sets of semistructured qualitative interviews.
Setting:
The study was conducted in 8 dental clinics in a Midwestern metropolitan area.
Participants:
In total, 70 DHCP participated in the first set of interviews; 63 DHCP participated in the second set of interviews.
Methods:
In September–November 2020 and March–October 2021, we conducted 2 sets of semistructured interviews: (1) PPE use in the dental community during COVID-19, and (2) feedback on the utility of an educational donning and doffing video.
Results:
Overall, 86% of DHCP reported having prior training. DHCP increased the use of PPE during COVID-19, specifically N95 respirators and face shields. DHCP reported real-world challenges to applying infection control methods, often resulting in PPE modification and reuse. DHCP reported double masking and sterilization methods to extend N95 respirator use. Additional challenges to PPE included shortages, comfort or discomfort, and compatibility with specialty dental equipment. DHCP found the educational video helpful and relevant to clinical practice. Fewer than half of DHCP reported exposure to a similar video.
Conclusions:
DHCP experienced significant challenges related to PPE access and routine use in dental clinics during the COVID-19 pandemic. An educational video improved awareness and uptake of appropriate PPE use among DHCP.
The transition from military service to civilian life is a high-risk period for suicide attempts (SAs). Although stressful life events (SLEs) faced by transitioning soldiers are thought to be implicated, systematic prospective evidence is lacking.
Methods
Participants in the Army Study to Assess Risk and Resilience in Servicemembers (STARRS) completed baseline self-report surveys while on active duty in 2011–2014. Two self-report follow-up Longitudinal Surveys (LS1: 2016–2018; LS2: 2018–2019) were subsequently administered to probability subsamples of these baseline respondents. As detailed in a previous report, a SA risk index based on survey, administrative, and geospatial data collected before separation/deactivation identified 15% of the LS respondents who had separated/deactivated as being high-risk for self-reported post-separation/deactivation SAs. The current report presents an investigation of the extent to which self-reported SLEs occurring in the 12 months before each LS survey might have mediated/modified the association between this SA risk index and post-separation/deactivation SAs.
Results
The 15% of respondents identified as high-risk had a significantly elevated prevalence of some post-separation/deactivation SLEs. In addition, the associations of some SLEs with SAs were significantly stronger among predicted high-risk than lower-risk respondents. Demographic rate decomposition showed that 59.5% (s.e. = 10.2) of the overall association between the predicted high-risk index and subsequent SAs was linked to these SLEs.
Conclusions
It might be possible to prevent a substantial proportion of post-separation/deactivation SAs by providing high-risk soldiers with targeted preventive interventions for exposure/vulnerability to commonly occurring SLEs.
During the years 1883-1886 different launches here were driven by aërial propellers or revolving sails, and the intention was a simultaneous utilisation of wind and steam power, nearly 80 per cent, of the wind directions being utilised, when sailing in a circular course. It was found that the efficiency of an aërial propeller, when correctly constructed, is a trifle superior (on account of the elasticity of the air) to that of a water propeller; at present, therefore, where the aerial propeller has come into practical use for driving aeroplanes its theory may perhaps attract attention.
The origin and the development of scientific disciplines has been a topic of reflection for several decades. The few extensive case studies support the thesis that scientific disciplines are not monolithic structures but can be characterized by distinct social, organizational and scientific–technical practices. Nonetheless, most disciplinary histories of genetics confine themselves largely to an uncontested account of the content of the discipline or occasionally institutional factors. Little attention is paid to the large number of researchers who, by their joint efforts, ultimately shaped the discipline. We contribute to this aspect of disciplinary historiography by discussing the role of women researchers at the Institute for Heredity Research, founded in 1914 in Berlin under the directorship of Erwin Baur, and the sister of the John Innes Institute at Cambridge. This paper investigates how and why Baur built a highly successful research programme that relied on the efforts of his female staff, whose careers, notably Elisabeth Schiemann's, are also assessed in toto. These women undertook the necessary ‘technoscience’ and in some cases innovative work and helped increase the prestige of the institute and its director. Together they played a pivotal role in the establishment of genetics in Germany. Without them the discipline would have developed much more slowly and along a divergent path.
The role of episodic mass loss in evolved massive stars is one of the outstanding questions in stellar evolution theory. Integral field spectroscopy of nebulae around massive stars provide information on their recent mass-loss history. η Car is one of the most massive evolved stars and is surrounded by a complex circumstellar environment. We have conducted a three-dimensional morpho-kinematic analysis of η Car’s ejecta outside its famous Homunculus nebula. SHAPE modelling of VLT MUSE data establish unequivocally the spatial cohesion of the outer ejecta and the correlation of ejecta with the soft X-ray emission.
In many developing countries, people rely on natural resources for subsistence and cash income. The trade ban on species listed as critically endangered by the International Union for the Conservation of Nature (IUCN) Red List may be counter-productive, as increasing the rarity and thus price of these species acts as a stimulus to illegal markets rather than a deterrent. Since illegal markets cannot have legal property rights, there is no basis for any form of sustainable harvesting based on property rights. The Malagsy radiated tortoise (Astrochelys radiata) is an example of a species that is threatened by domestic and international trade; legalizing international trade could, under certain circumstances, provide financial incentives that might effectively reduce the domestic trade and subsistence harvest of this animal. This paper argues this critically-endangered species may be more effectively conserved by assigning trading rights to local communities, rather than demanding a trade ban that cannot be enforced successfully.
At the Institute of Microstructure Technology (IMT) of the Karlsruhe Institute of Technology (KIT), a new type of refractive X-ray optics has been developed. Owing to its comparably easy fabrication method and the large aperture, the so-called Rolled X-ray Prism Lenses (RXPL) have the potential to be used with X-ray tubes in an industrial environment as a low-cost alternative to existing optics. The lens itself is built out of a micro-structured foil which is cut into shape and rolled around a winding core to form a refracting element for X-rays. The resulting refractive structure can be used as illumination optics. Diffractometry experiments with an NIST 1976a sample were performed and showed up to an 18-fold enhanced integrated intensity compared to that acquired with a steel tube collimator.
In the present study, we hypothesised whether in vitro digestion of salmon oil would release different amounts of PUFA depending on the origin of the lipolytic enzymes used. For this purpose, in vitro digestion of salmon oil (SO) was performed using human duodenal juice (HDJ) or a commercial enzyme preparation consisting of porcine pancreatin and bile (PB). The lipolytic effect was determined by measuring the release of fatty acids (FA) using solid-phase extraction and GC–flame ionisation detection, withdrawing samples every 20 min during digestion. The amount of FA released indicated that a plateau was reached after 80 min with approximately similar amounts of FA detected using both HDJ and PB (379 (sd 18) and 352 (sd 23) mg/g SO, respectively). However, the release of 18 : 2, EPA (20 : 5) and DHA (22 : 6) was significantly different during in vitro digestion. At 80 min, HDJ and PB released 43 and 33 % of 18 : 2, 14 and 9 % of EPA and 11 and 9 % of DHA, respectively. Both enzyme preparations released approximately the same amounts of the other FA analysed. The effect of the addition of bile salts (BS) was significantly different in the two enzyme systems, where porcine pancreatin highly responded to the increase in BS concentration, in contrast to HDJ.
LOFAR (Low Frequency Array) is an innovative radio telescope optimized for the frequency range 30–240 MHz. The telescope is realized as a phased aperture array without any moving parts. Digital beam forming allows the telescope to point to any part of the sky within a second. Transient buffering makes retrospective imaging of explosive short-term events possible. The scientific focus of LOFAR will initially be on four key science projects (KSPs): (i) Detection of the formation of the very first stars and galaxies in the universe during the so-called epoch of reionization by measuring the power spectrum of the neutral hydrogen 21-cm line (Shaver et al. 1999) on the ∼ 5′ scale; (ii) Low-frequency surveys of the sky with of order 108 expected new sources; (iii) All-sky monitoring and detection of transient radio sources such as γ-ray bursts, X-ray binaries, and exo-planets (Farrell et al. 2004); and (iv) Radio detection of ultra-high energy cosmic rays and neutrinos (Falcke & Gorham 2003) allowing for the first time access to particles beyond 1021 eV (Scholten et al. 2006). Apart from the KSPs open access for smaller projects is also planned. Here we give a brief description of the telescope.
By
Peter H. Vogt, Section Molecular Genetics and Infertility, Department of Gynecology Endocrinology and Reproductive Medicine, University of Heidelberg, Heidelberg, Germany
From mouse and Drosophila knock out experiments it has been deduced that the products of more than 3000 genes are involved in the genetic control regulating the expression of male (and female) fertility (Cooke and Saunders, 2002, Hackstein et al., 2000; Matzuk and Lamb, 2002). In human, the molecular identification of male fertility genes is hampered by the fact that human is not an experimental species. An infertile man is only recognised after the couple desiring for a child has asked for some therapeutic treatments in an infertility clinic.
Genetic lesions causing male infertility can be roughly grouped in three classes: (I) Chromosomal aneuploidies and rearrangements where batteries of genes on specific chromosomes have increased or decreased their expression dosage or have changed their normal nuclear territorium; (II) submicroscopic deletions (i.e. the genomic AZF deletions) where deletions or rearrangements of multiple genes – mapped in a molecular neighbourhood – have lost or altered their normal expression pattern and (III) single gene defects where the expression of a single gene is changed or lost causing then male infertility (e.g. the CFTR gene). This chapter offers a basic science perspective to the molecular genetic principles causing male infertility in the three different genetic-abnormality groups. Thereby one aim is to point to the practical prerequisites which will be needed for their proper analysis in the infertility clinic reducing time and costs and increasing the patient's success rate for conceiving a child without an inherited genetic abnormality.
Background and aim: The neuromuscular effects of a bolus dose of rocuronium 0.6 mg kg−1 under propofol anaesthesia in renal failure patients are prolonged compared to healthy patients. The present study aims to describe the neuromuscular effects of 0.3 mg kg−1 rocuronium under propofol anaesthesia in patients with renal failure and to compare these effects with healthy control patients. Methods: With institutional approval and informed consent, 18 healthy patients and 18 patients with renal failure took part in this prospective open label study. The renal failure patients were undergoing either renal transplantation or insertion of a shunt. Rocuronium 0.3 mg kg−1 was given intravenously after induction of anaesthesia with propofol 1–2 mg kg−1 and fentanyl 2 μg kg−1. Propofol 6–12 mg kg−1 h−1 was used for maintenance of anaesthesia. Four acceleromyographic responses of the thumb after supramaximal stimulation of the ulnar nerve using surface electrodes at 2 Hz every 15 s were measured and recorded. The onset time, the time to recovery of the first twitch to 25% recovery and the time to a train-of-four ratio of 0.7 were all recorded. Wilcoxon rank sum testing was used to compare the pharmacodynamics and to see if medication, gender or electrolytes influenced the duration of the block. P < 0.05 was significant. Results: No statistical differences were seen in the neuromuscular blocking effects of rocuronium between the two groups but there was a significant difference (P < 0.00001) in the variability of the total duration of the block. Conclusions: Rocuronium 0.3 mg kg−1 is suitable for use in patients with renal failure when endotracheal intubation and neuromuscular block for a short period of time are needed. Tracheal intubation is facilitated within 4 min and the block can be antagonized within 20 min.
We present preliminary analysis of new HST observations of the transiting extrasolar planet HD 209458b. Photometric observations were obtained with the Fine Guidance Sensor (FGS) on the Hubble Space Telescope (HST), providing milli-mag precision and high time resolution (40 Hz). The FGS photometry allows us to derive precise stellar/orbital parameters (ephemeris, inclination, limb darkening) and planetary radius, and also allows a search for the presence of planetary rings and satellites. We discuss preliminary results and two approaches to modelling the observations.
Determining the ubiquity of top-down control effects of predators on their prey and ecosystem processes is important for understanding community and ecosystem-level consequences that may result from predator loss. We conducted experiments at two spatial scales to investigate the effects of terrestrial frogs (Eleutherodactylus coqui) on aerial and litter invertebrates, plant growth and herbivory, and litter decomposition. At both scales, frogs reduced aerial invertebrates and leaf herbivory, but had no effect on litter invertebrates. At the smaller scale, frogs increased foliage production rates, measured as the number of new leaves and new leaf area produced, by 80% and decomposition rates by 20%. The influence of E. coqui on increasing primary productivity and decomposition rates at the smaller scale appeared to be a result of elimination and excretion rather than of controlling prey. While the results provide evidence for frogs controlling herbivorous prey at both scales, species effects on ecosystem processes were only detectable at the smaller scale. The results highlight the difficulties in conducting experiments at large spatial scales. The findings from this study imply that the loss of amphibians and other species of higher trophic levels may affect nutrient cycling rates in tropical forests.
Kjeldsen et al. (1995) detected excess power in the GO subgiant η Boo from measurements of Balmer-line equivalent widths. The excess was at the expected level, and these authors were able to extract frequency separations and individual frequencies which agreed well with theoretical models (Christensen-Dalsgaard et al., 1995; Guenther & Demarque, 1996). A more detailed discussion of theoretical models for η Bootis was given by Di Mauro & Christensen-Dalsgaard (2001).
Kjeldsen et al. (1995) estimated the average amplitude of the strongest modes to be 7 times solar, corresponding to 1.6 m/s in velocity. 13 individual oscillation modes were identified consistent with a large frequency separation of 40.3 μHz. We note, however, that a search for velocity oscillations in this star by Brown et al. (1997) failed to detect a signal, setting limits at a level below that expected on the basis of the Kjeldsen et al. result.
In this paper we report further observations made in 1998. We observed this star in Balmer-line equivalent width with the 2.5-m Nordic Optical Telescope and in velocity with the 24-inch Lick CAT.
In the last 30 years investigations into side-effects of pesticides on beneficial organisms have gained more and more importance. The increase in knowledge is the basis for reducing the undesirable effects of pesticide applications, which among others, is an important principle of integrated production (Cross & Dickler, 1994). Whereas in former years companies presented data on side-effects of a pesticide on a voluntary basis to the authorities for the registration procedure, in 1986 this became obligatory in Germany (Anon., 1986; Brasse, 1990) and recently in all European countries, as regulated by the Council Directive 91/414/EEC. Factors to be considered when studying side-effects were published by Franz (1974). The IOBC/WPRS working group ‘Pesticides and Beneficial Organisms’, founded in 1974, has contributed considerably to research of side-effects caused by pesticides. The group is working (in close co-operation with registration authorities, EPPO) on the development, improvement, and validation of test methods (laboratory, semi-field, and field) and on rearing methods, and it carries out joint testing programmes to investigate the impact of pesticides on about 30 beneficial organisms (Hassan et al., 1983, 1985, 1987, 1988, 1991, 1994; Hassan, 1988, 1989, 1992, 1994; Samsøe-Petersen, 1989; Vogt, 1994; Sterk et al., 1999). Comprehensive data on research findings focusing on the interaction of pesticides with entomophagous arthropods have been published by Croft (1990).