Scientific echosounder data provide a predator's view of Antarctic krill (Euphausia superba).

Raw acoustic data were collected in East Antarctica from the RSV Aurora Australis during two surveys: the Krill Availability, Community Trophodynamics and AMISOR Surveys (KACTAS) and the Krill Acoustics and Oceanography Survey (KAOS) in the East Antarctic (centre coordinate 66.5° S, 63° E). The KACTAS survey was conducted between 14th to 21st January and 2001, and the KAOS survey was conducted between 16 January and 1 February 2003. We examine the Antarctic krill (Euphausia superba) component of these surveys and provide scientific echosounder (EK500 and EK60) data collected at 38, 120 and 200 kHz, cold water (-1 °C) echosounder calibration parameters and accompanying krill length frequency distributions obtained from trawl data. We processed the acoustic data to apply calibration values and remove noise. The processed data were used to isolate echoes arising from swarms of krill and to estimate metrics for each krill swarm, including internal density and individual swarm biomass. The krill swarm data provide insights to a predators' views of krill distribution and density.

The characteristics of krill swarms in relation to aggregating Antarctic blue whales.

We model the presence of rare Antarctic blue whales (Balaenoptera musculus intermedia) in relation to the swarm characteristics of their main prey species, Antarctic krill (Euphausia superba). A combination of visual observations and recent advances in passive acoustic technology were used to locate Antarctic blue whales, whilst simultaneously using active underwater acoustics to characterise the distribution, size, depth, composition and density of krill swarms. Krill swarm characteristics and blue whale presence were examined at a range of spatiotemporal scales to investigate sub meso-scale (i.e., <100 km) foraging behaviour. Results suggest that at all scales, Antarctic blue whales are more likely to be detected within the vicinity of krill swarms with a higher density of krill, those found shallower in the water column, and those of greater vertical height. These findings support hypotheses that as lunge-feeders of extreme size, Antarctic blue whales target shallow, dense krill swarms to maximise their energy intake. As both Antarctic krill and blue whales play a key role in the Southern Ocean ecosystem, the nature of their predator-prey dynamics is an important consideration, not only for the recovery of this endangered species in a changing environment, but for the future management of Antarctic krill fisheries.

Severely impaired health status of non-notified Q fever patients leads to an underestimation of the true burden of disease.

Q fever patients are often reported to experience a long-term impaired health status, including fatigue, which can persist for many years. During the large Q fever epidemic in The Netherlands, many patients with a laboratory-confirmed Coxiella burnetii infection were not notified as acute Q fever because they did not fulfil the clinical criteria of the acute Q fever case definition (fever, pneumonia and/or hepatitis). Our study assessed and compared the long-term health status of notified and non-notified Q fever patients at 4 years after onset of illness, using the Nijmegen Clinical Screening Instrument (NCSI). The study included 448 notified and 193 non-notified Q fever patients. The most severely affected subdomain in both patient groups was 'Fatigue' (50·5% of the notified and 54·6% of the non-notified patients had severe fatigue). Long-term health status did not differ significantly between the notified and non-notified patient groups, and patients scored worse on all subdomains compared to a healthy reference group. Our findings suggest that the magnitude of the 2007-2009 Q fever outbreak in The Netherlands was underestimated when only notified patients according to the European Union case definition are considered.

Levels of agreement between student and staff assessments of clinical skills in performing cavity preparation in artificial teeth.

OBJECTIVE: To determine the level of agreement between staff and students' assessment of clinical skills in performing tasks related to cavity preparation on a traditional dental manikin. METHODS: Two studies were conducted with two successive student cohorts: Study 1-138 year 1 BDS students in a 2009/10 cohort and Study 2-135 students in a 2010/11 cohort. Staff members and students rated the students' performance in preparing a cavity on a traditional dental manikin using artificial teeth: hand-held (Study 1) and located in a lower jaw (Study 2). A 5-item criterion-related scoring rubric was developed. The rubric assessed students' abilities to hold the instrument correctly, determine the angle of entry to the tooth, remove the caries, conserve healthy tissues and avoid pulp exposure. RESULTS: Agreement between the students' self-assessment and the staff's assessment was high for three of the five criteria (i.e. removal of artificial caries on the cavity wall, removal of artificial caries from the cavity floor and avoidance of pulp exposure). Levels of agreement for the remaining two criteria were moderate. A change in task difficulty affected the levels of agreement between staff and students, such that the more difficult the task, the greater the discrepancy in ratings. CONCLUSIONS: Students tend to overrate the quality of their performance when compared with staff ratings. Task difficulty has an impact on levels of agreement.

Femtosecond study of the deuteron-transfer dynamics of naphtol salts in water.

We study the rate and mechanism of deuteron transfer from the photoacids 1-naphtol-4-sulfonate (1-NPS) and 2-naphtol-3,7-disulphonate (2-NPS) to acetate base in aqueous (D(2)O) solution. The photoacids are activated by excitation with 100 fs laser pulses at 267 nm. The electronic absorption and stimulated emission spectra of the photoacid and the conjugate photobase and the vibrational absorption spectra of the hydrated deuteron and the acetate base are probed with broad-band delayed 100 fs pulses at visible and mid-infrared wavelengths, respectively. A significant fraction of the deuteron transfer events are observed to occur on a timescale of <1 ps within hydrogen-bonded contact photoacid-acetate complexes. For 1-NPS, this fraction is much higher than for 2-NPS. At later delay times, the reaction is dominated by deuteron transfer through short-living water wires of different lengths that connect the photoacid and the acetate base.

Direct observation of proton transfer in ice Ih using femtosecond spectroscopy.

We studied proton transfer in ice samples containing the photoacid 8-hydroxypyrene-1,3,6-trisulfonic acid and the base sodium formate using femtosecond pump-probe spectroscopy. Pump pulses, centered at a wavelength of 400 nm, electronically excited the photoacid molecules which released their protons. These protons subsequently traveled from the photoacid through the ice lattice to the base and were observed as they arrived at the base using the transient absorption of an infrared probe pulse. Both the temperature and concentration dependence of the proton transfer dynamics were modeled using a discrete set of two intrinsic transfer rates, associated with short and long-range proton transfer, respectively. Proton transfer in configurations where the acid and base were separated by up to about two water molecules, was found to occur on a approximately 1 ps time scale for all temperatures (240-270 K). Long range direct proton transfer through water wires of about four water molecules in length was found to occur on a approximately 300 ps time scale at 270 K. This latter process was observed to slow down significantly with decreasing temperature, with an activation energy of approximately 80 kJ/mol.

Making a mark--taking assessment to technology.

During any course of study, students are assessed usually through a range of methods which may include written examinations, coursework assignments, professional practice, oral tests and practical examinations. This article considers the various forms of assessment in dental education and how information and communication technology is being applied to them. As innovative teaching and learning methods such as computer simulations are introduced, the assessment of results, successes and failures is taking on new forms in many traditional courses. The web is also spreading its tentacles into assessment, with the benefits of offering almost instant feedback and support. However, technology brings its own problems, not least by making ever more ingenious methods of plagiarism easier. Educational establishments, therefore, must be aware of such problems and have policies in place to counteract them.

An intricate web - designing and authoring a web-based course.

The Internet offers a great opportunity to deliver dental education in new ways. However, to achieve the maximum benefit from this medium, it is necessary to understand its strengths and weaknesses and, above all, not to lose sight of the key principle that in education it is the message and not the messenger (the content and not the medium) that should be given priority. After a brief introduction, this paper considers the principles of designing online programmes. It stresses the need for ensuring that students have easy access to the materials that have been designed and then describes 'learning objects' and virtual learning environments (VLEs). It concludes that with some notable exceptions, dental educators have hardly begun to grasp the benefits of web-based teaching and learning.

Parallel proton transfer pathways in aqueous acid-base reactions.

We study the mechanism of proton transfer (PT) between the photoacid 8-hydroxy-1,3, 6-pyrenetrisulfonic acid (HPTS) and the base chloroacetate in aqueous solution. We investigate both proton and deuteron transfer reactions in solutions with base concentrations ranging from 0.25 M to 4 M. Using femtosecond midinfrared spectroscopy, we probe the vibrational responses of HPTS, its conjugate photobase, the hydrated proton/deuteron, and chloroacetate. The measurement of these four resonances allows us to follow the sequence of proton departure from the acid, its uptake by the water solvent, and its arrival at the base. In recent studies it was shown that proton transfer to carboxylate bases proceeds via Grotthuss conduction through a water wire connecting the acid and the base [Mohammed et al., Science 310, 83 (2005);Agnew. Chem. Int. Ed. 46, 1458 (2007);Siwick and Bakker, J. Am. Chem. Soc. 129, 13412 (2007); J. Phys. Chem. B 112, 378 (2008)]. Here we show that, for the weaker base chloroacetate, an alternative channel for proton transfer arises. In this channel the proton is first transferred to the water solvent and only later taken up from the water by the base. We study the base concentration dependence of the two competing channels.

Top of the pops--CD-ROM and DVDs in dental education.

In many ways the CD-ROM was the first digital teaching aid, the precursor of what was to develop into e-learning. Launched in the mid-1980s, its first educational application was as a storage medium for reference material. Since then the list of its uses has grown as has its storage capacity, ability to hold data in different formats - text, audio image and video - and its interactive properties have allowed developers to produce discs which enhance both the processes and enjoyment of teaching and learning. In this article the stages involved in production of an educational CD-ROM, typical content and the benefits are considered, prior to a review of a number discs that have been used in dental education. The varied titles reveal how versatile CD-ROMs can be. They range from a course showing students the importance of good patient communications and how to achieve them, to an in-depth exposition in the 'Head and Neck Anatomy' disc, a subject important not just for dentistry, but for other medical disciplines as well. The last section of this article considers a study undertaken amongst its students by the Open University, which investigated the effectiveness of CD-ROM in education. In conclusion, it can be said that although the CD-ROM format is a versatile, popular and valuable aid, with the emergence of DVD it may soon be seen as 'old technology' and replaced by the newer format.

Long-range proton transfer in aqueous Acid-base reactions.

We study the mechanism of proton transfer (PT) in the aqueous acid-base reaction between the photoacid 8-hydroxy-1,3,6-pyrenetrisulfonic acid (HPTS) and acetate by probing the vibrational resonances of HPTS, acetate, and the hydrated proton with femtosecond mid-infrared laser pulses. We find that PT takes place in a distribution of hydrogen-bound reaction complexes that differ in the number of water molecules separating the acid and the base. The number of intervening water molecules ranges from 0 to 5, which, together with a strongly distance-dependent PT rate, explains the observed highly nonexponential reaction kinetics. The kinetic isotope effect for the reaction is determined to be 1.5, indicating that tunneling does not play a significant role in the transfer of the proton. Rather, the transfer mechanism is best described in terms of the adiabatic PT picture as it has been formulated by Hynes and co-workers [Staib, A.; Borgis, D.; Hynes, J. T. J. Chem. Phys. 1995, 102, 2487. Ando, K.; Hynes, J. T. J. Phys. Chem. B 1997, 101, 10464.], where solvent fluctuations play an essential role in forming the correct hydrogen-bond configuration and solvent polarization to facilitate PT.

Age-specific seroprevalence to an immunodominant Cryptosporidium sporozoite antigen in a Brazilian population.

The seroepidemiology of Cryptosporidium infection was investigated in a representative sample of a normal population in the State of Sao Paulo, Brazil using a recombinant form of the immunodominant 27-kDa sporozoite antigen. IgG seropositivity was low in infants following loss of maternal antibody but quickly increased to approximately 60% by 5 years, then 80% by the age of 10 years, after which prevalence remained constant. The broad range of antibody concentrations is consistent with previous reports that the IgG response to C. parvum is short-lived. There is also evidence that average antibody concentrations increase with age. Results suggest that the recombinant antigen may be a more sensitive method of measuring seroprevalence than the native antigen in Western blot. Although cross-sectional studies can provide an insight into the epidemiology of C. parvum in normal populations, further studies investigating the dynamics of the humoral immune responses to Cryptosporidium and the use of serology in epidemiological studies are required.

Medication safety program reduces adverse drug events in a community hospital.

BACKGROUND: There is widespread interest in improving medication safety, particularly in the hospital setting. Numerous suggestions have been made as to how this should be done, but there is a paucity of data demonstrating the effectiveness of any of the interventions that have been proposed. OBJECTIVES: To assess the impact of a wide ranging, community hospital based patient safety program on patient harm as measured by the rate of adverse drug events. DESIGN: An audit of discharged hospital patients was conducted from January 2001 to December 2003. Baseline data were collected for the first 6 months and multiple drug protocols and other interventions were instituted on the nursing units and in the pharmacy department over the subsequent 9 months (transition period). These interventions were largely based on information about medication risks acquired from internal medication event reporting. Each month of the study adverse drug events (ADE) were sought from a random sample of inpatient charts. A trigger tool was used to detect clues to ADEs, the presence of which was confirmed or excluded by detailed manual chart review. The severity of these events was categorized using the classification system of the National Coordinating Council for Medication Error and Reporting and Prevention. MAIN OUTCOME MEASURES AND RESULTS: Median ADEs per 1000 doses of medication dispensed declined significantly from 2.04 to 0.65 (p<0.001). Median ADEs per 100 patient days declined significantly from 5.07 to 1.30 (p<0.001). The proportion of inpatients with one or more ADE in the baseline period was 31% and declined threefold (p<0.001). The severity of reported medication events also declined. The number of ADEs associated conclusively with patient harm was 1.67 per total doses delivered in the baseline period and declined eightfold (p<0.001). CONCLUSION: The implementation of a carefully planned series of low cost interventions focused on high risk medications, driven by information largely from internal event reporting, and designed to improve a hospital's medication safety leads to a significant decrease in patient harm.

Serological survey of anti-group A rotavirus IgM in UK adults.

Rotaviral associated disease of infants in the UK is seasonal and infection in adults not uncommon but the relationship between these has been little explored. Adult sera collected monthly for one year from routine hospital samples were screened for the presence of anti-group A rotavirus immunoglobulin M class antibodies as a marker of recent infection. Anti-rotavirus IgM was seen in all age groups throughout the year with little obvious seasonal variation in the distribution of antibody levels. IgM concentrations and the proportion seropositive above a threshold both increased with age with high concentrations consistently observed in the elderly. Results suggest either high infection rates of rotavirus in adults, irrespective of seasonal disease incidence in infants, IgM persistence or IgM cross-reactivity. These results support recent evidence of differences between infant and adult rotavirus epidemiology and highlight the need for more extensive surveys to investigate age and time related infection and transmission of rotavirus.

Nosocomial primary bloodstream infections in intensive care unit patients in a nonteaching community medical center: a 21-month prospective study.

All patients admitted to the medical and surgical intensive care units of a 500-bed nonteaching suburban hospital were followed prospectively for the occurrence of nosocomial primary bloodstream infections for 21 months. The incidence of primary bloodstream infection was 38 (1%) of 3163 patients; among patients with central venous catheters, it was 34 (4%) of 920 patients, or 4.0 infections per 1000 catheter-days. Ventilator-associated pneumonia, congestive heart failure, and each intravascular catheter inserted were independently associated with the development of a nosocomial primary bloodstream infection. Among infected patients, the crude mortality rate was 53%, and these patients had longer stays in intensive care units and the hospital than did uninfected patients. Bloodstream infection, however, was not an independent risk factor for death. The incidence, risk factors, and serious outcomes of bloodstream infections in a nonteaching community hospital were similar to those seen in tertiary-care teaching hospitals.

CD-ROM nutrient analysis database assists self-monitoring behavior of active duty Air Force personnel receiving nutrition counseling for weight loss.

This study observed the effect of using a computerized vs manual method of self-monitoring among Air Force personnel receiving nutrition counseling for weight loss. Subjects who enrolled during the first 2 weeks of the 4-week recruitment period completed food records for 6 weeks using a CD-ROM nutrient database (intervention group) whereas those who enrolled during the last 2 weeks used a food record booklet (comparison group). Of the 42 subjects (n = 23 intervention group and n = 19 comparison group), only 113 intervention and 11 comparison group subjects (57% of study enrollees) submitted at least 1 food record during the study and were included in the analysis, which included review of pre- and poststudy questionnaires, food records, and focus group data. There were no significant differences between the number of days per week documented or average number of items recorded daily. All 9 intervention as compared to 2 comparison group subjects who completed a poststudy questionnaire searched for lower-energy and lower-fat items and reported changing their dietary intake as a result. All intervention group subjects who participated in a focus group (n=6) had favorable comments about using the CD-ROM for monitoring and changing eating habits, indicating that it is a beneficial self-monitoring tool. Participants enjoyed the immediate dietary feedback, and computerized food records may be easier to interpret by nutrition counselors. A number of computerized nutrient databases are available to assist patients and consumers in managing nutritional concerns.

Venomous snake husbandry in Thailand.

A captive breeding program for venomous Thai snakes was established at the Queen Saovabha Memorial Institute at Bangkok, Thailand. This was necessary to secure a stable, healthy, and species-confirmed source of snake venom for antivenom production. In 1994, wild-caught specimens were collected, sexed, quarantined, and housed appropriately. All data in this report, with the exclusion of Table 6, were collected from 1994 to 1997. Two species were bred successfully in captivity to date during this study period. Although captive breeding has not yet been achieved with all species and subspecies, our early success was encouraging.

Isolation and phenotypic characterization of Pseudomonas aeruginosa pseudorevertants containing suppressors of the catabolite repression control-defective crc-10 allele.

The amiE gene encodes an aliphatic amidase capable of converting fluoroacetamide to the toxic compound fluoroacetate and is one of many genes whose expression is subject to catabolite repression control in Pseudomonas aeruginosa. The protein product of the crc gene, Crc, is required for repression of amiE and most other genes subject to catabolite repression control in this bacterium. When grown in a carbon source such as succinate, wild-type P. aeruginosa is insensitive to fluoroacetamide (due to repression of amiE expression). In contrast, mutants harboring the crc-10 null allele cannot grow in the presence of fluoroacetamide (due to lack of repression of amiE). Selection for succinate-dependent, fluoroacetamide-resistant derivatives of the crc-10 mutant yielded three independent pseudorevertants containing suppressors that restored a degree of catabolite repression control. Synthesis of Crc protein was not reestablished in these pseudorevertants. All three suppressors of crc-10 were extragenic, and all three also suppressed a Delta crc::tetA allele. In each of the three pseudorevertants, catabolite repression control of amidase expression was restored. Catabolite repression control of mannitol dehydrogenase production was also restored in two of the three isolates. None of the suppressors restored repression of glucose-6-phosphate dehydrogenase or pyocyanin production.

The spherical aberration of the crystalline lens of the human eye.

The in vivo spherical aberration of the lenses of 26 subjects was estimated from the measured total aberration of the eye and that predicted from the measured shape of the anterior corneal surface. Since it was only possible to estimate the aberration contribution from the posterior corneal surface, its value led to an uncertainty in the final aberration level of the lens. For all the subjects and for a wide range of possible aberration levels at the posterior corneal surface, the spherical aberration of the relaxed lens was found to be negative.

Fathers' participation in family research: is there a self-selection bias?

The representativeness of fathers who participate in family research was examined among 661 families. Approximately two thirds of eligible fathers participated. Mothers' and observers' reports on families of participating and non-participating fathers were compared. Participating fathers underrepresented fathers with less education, later-born children, more ambivalent marriages, partners with more traditional child-rearing beliefs, families with less optimal parenting environments, and infants who were unplanned, had more difficult temperaments, and were less healthy. Also underrepresented were ethnic minority families and working-class fathers. However, no differences were found in regard to child gender, family income, mothers' psychosocial functioning, either parent's employment experiences, or child-care arrangements. Implications for the generalizability of findings and the recruitment of fathers are discussed.