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By
Gary L. Mullen, Pennsylvania State University, University Park, PA,
Daqing Wan, University of California Irvine, CA,
Qiang Wang, Carleton University, Ottawa
Objective. Ornithonyssus sylviarum (northern fowl mite) and Menacanthus stramineus (chicken body louse) are key poultry pests currently controlled by exclusion or pesticide application. We studied how host beak condition affected their populations over time and how the lice and mites might interact on a host. Methods. Beak-trimmed or beak-intact white leghorn hens were infested initially with either mites or lice and subsequently challenged using the alternate ectoparasite species (reciprocal transfer), while other hens harboured only the initial ectoparasite species. Results. Beak-trimmed hens had far higher ectoparasite numbers relative to beak-intact hens, and the 2 ectoparasites showed evidence of grooming-mediated competitive asymmetry. On beak-trimmed hens, larger numbers of lice quickly nearly completely excluded mites in competition for enemy-free space (lower abdomen), while in the reciprocal transfer mites did not affect louse numbers on beak-trimmed hosts. The 2 ectoparasites co-existed on beak-intact hens, which were better able to defend the lower abdomen habitat by grooming. Conclusion. Lice are somewhat less damaging and much easier to control relative to mites, and might be used to eliminate mites in commercial, beak-trimmed flocks. Beak trimming impairs host grooming and contributes greatly to the high ectoparasite populations seen in commercial flocks. The study adds incentives for poultry breeders to develop more docile hen strains that can be held without beak trimming. This has advantages both to welfare advocates and producers who may no longer need to use insecticides for pest control or be concerned about worker exposure to pesticides.
The goal of this effort was to reduce central venous catheter (CVC)-associated bloodstream infections (BSIs) in pediatric intensive care unit (ICU) patients by means of a multicenter evidence-based intervention.
Methods.
An observational study was conducted in 26 freestanding children's hospitals with pediatric or cardiac ICUs that joined a Child Health Corporation of America collaborative. CVC-associated BSI protocols were implemented using a collaborative process that included catheter insertion and maintenance bundles, daily review of CVC necessity, and daily goals. The primary goal was either a 50% reduction in the CVC-associated BSI rate or a rate of 1.5 CVC-associated BSIs per 1,000 CVC-days in each ICU at the end of a 9-month improvement period. A 12-month sustain period followed the initial improvement period, with the primary goal of maintaining the improvements achieved.
Results.
The collaborative median CVC-associated BSI rate decreased from 6.3 CVC-associated BSIs per 1,000 CVC-days at the start of the collaborative to 4.3 CVC-associated BSIs per 1,000 CVC-days at the end of the collaborative. Sixty-five percent of all participants documented a decrease in their CVC-associated BSI rate. Sixty-nine CVC-associated BSIs were prevented across all teams, with an estimated cost avoidance of $2.9 million. Hospitals were able to sustain their improvements during a 12-month sustain period and prevent another 198 infections.
Conclusions.
We conclude that our collaborative quality improvement project demonstrated that significant reduction in CVC-associated BSI rates and related costs can be realized by means of evidence-based prevention interventions, enhanced communication among caregivers, standardization of CVC insertion and maintenance processes, enhanced measurement, and empowerment of team members to enforce adherence to best practices.
Public figures are at increased risk of attracting unwanted attention in the form of intrusions, stalking and, occasionally, attack. Whereas the potential threat to the British Royal Family from terrorists and organized groups is clearly defined, there is a dearth of knowledge about that from individual harassers and stalkers. This paper reports findings from the first systematic study of this group.
Method
A retrospective study was conducted of a randomly selected stratified sample (n=275) of 8001 files compiled by the Metropolitan Police Service's Royalty Protection Unit over 15 years on inappropriate communications or approaches to members of the British Royal Family. Cases were split into behavioural types. Evidence of major mental illness was recorded from the files. Cases were classified according to a motivational typology. An analysis was undertaken of associations between motivation, type of behaviour and mental illness.
Results
Of the study sample, 83.6% were suffering from serious mental illness. Different forms of behaviour were associated with different patterns of symptomatology. Cases could be separated into eight motivational groups, which also showed significant differences in mental state. Marked differences in the intrusiveness of behaviour were found between motivational groups.
Conclusions
The high prevalence of mental illness indicates the relevance of psychiatric intervention. This would serve the health interests of psychotic individuals and alleviate protection concerns without the necessity of attempting large numbers of individual risk predictions. The finding that some motivations are more likely to drive intrusive behaviours than others may help focus both health and protection interventions.
Important material properties of dielectric oxide films fabricated by aqueous chemical solution deposition, such as crystallization, topography, contamination and interfacial layer were evaluated and related to the films' dielectric properties.
Functional ultrathin films (<20 nm thickness) of zirconia, barium zirconate and strontium niobate were deposited. The films were all subjected to the same thermal treatment, based on the high similarity of their precursors' thermal decomposition behavior. The evolution of the films' chemical purity as a function of temperature and the effect of annealing on the interfacial SiO2 layer was studied by grazing angle ATR-FTIR. The films' crystallization behavior was dependent on film thickness and composition as shown by high temperature XRD. C-V characterization of the films demonstrated a k-value in the same order of magnitude as for the ZrO2 reference material. This is lower than the bulk material's value, thus leaving room for further optimization of the current materials or alternatively selection of other material compositions.
Mental health clinicians are frequently asked to assess the risks presented by patients making threats to kill, but there are almost no data to guide such an evaluation.
Method
This data linkage study examined serious violence following making threats to kill and the potential role of mental disorder. A total of 613 individuals convicted of threats to kill had their prior contact with public mental health services established at the time of the index offence. The group's subsequent criminal convictions were established 10 years later using the police database. Death from suicidal or homicidal violence was also established.
Results
Within 10 years, 44% of threateners were convicted of further violent offending, including 19 (3%) homicides. Those with histories of psychiatric contact (40%) had a higher rate (58%) of subsequent violence. The highest risks were in substance misusers, mentally disordered, young, and those without prior criminal convictions. Homicidal violence was most frequent among threateners with a schizophrenic illness. Sixteen threateners (2.6%) killed themselves, and three were murdered.
Conclusions
In contrast to the claims in the literature that threats are not predictive of subsequent violence, this study revealed high rates of assault and even homicide following threats to kill. The mentally disordered were over-represented among threat offenders and among those at high risk of subsequent violence. The mentally disordered threateners at highest risk of violence were young, substance abusing, but not necessarily with prior convictions. Those who threaten others were also found to be at greater risk of killing themselves or being killed.
In May 2000, public health authorities in Dublin, Ireland, identified a cluster of unexplained severe illness among injecting drug users (IDUs). Similar clusters were also reported in Scotland and England. Concurrent investigations were undertaken to identify the aetiology and source of the illnesses. In Dublin, 22 IDUs were identified with injection-site inflammation resulting in hospitalization or death; eight (36%) died. Common clinical findings among patients with severe systemic symptoms included leukaemoid reaction and cardiogenic shock. Seventeen (77%) patients reported injecting heroin intramuscularly in the 2 weeks before illness. Of 11 patients with adequate specimens available for testing, two (18%) were positive by 16S rDNA PCR for Clostridium novyi. Clinical and laboratory findings suggested that histotoxic Clostridia caused a subset of infections in these related clusters. Empiric treatment for infections among IDUs was optimized for anaerobic organisms, and outreach led to increased enrolment in methadone treatment in Dublin. Many unique legal, medical, and public health challenges were encountered during the investigation of this outbreak.
The lack of prospective studies and data on male victims leaves major questions regarding associations between child sexual abuse and subsequent psychopathology.
Aims
To examine the association between child sexual abuse in both boys and girls and subsequent treatment for mental disorder using a prospective cohort design.
Method
Children (n=16L2; 1327 female) ascertained as sexually abused at the time had their histories of mental health treatment established by data linkage and compared with the general population of the same age over a specified period.
Results
Both male and female victims of abuse had significantly higher rates of psychiatric treatment during the study period than general population controls (12.4% v. 3.6%). Rates were higher for childhood mental disorders, personality disorders, anxiety disorders and major affective disorders, but not for schizophrenia. Male victims were significantly more likely to have had treatment than females (22.8% v. 10.2%).
Conclusions
This prospective study demonstrates an association between child sexual abuse validated at the time and a subsequent increase in rates of childhood and adult mental disorders.
Substance abuse and addiction are difficult problems both theoretically and clinically in pain management and palliative care. Cancer patients with histories of substance abuse are often seen by palliative care specialists, especially in community-based settings. Whereas concurrent drug abuse is problematic, there is the additional problem regarding the diagnosis and understanding of the less obvious aberrant drug-taking behaviors sometimes in evidence in the treatment of patients without formal psychiatric histories of substance use disorders. Such aberrant drug-taking behavior can be manifest, for example, when a patient with advanced disease and pain is unilaterally escalating drug doses, is using medications to treat other symptoms, or when prescriptions are being mishandled. The clinician is challenged to understand such circumstances and plan interventions accordingly. Once these aberrant behaviors are identified the clinician must decide on a course of action that is fair and in the best interests of the patient as well as his or her own career. Thus, the problem of chemical dependence and drug abuse spans a continuum from formal psychiatric disorders to problematic behaviors in the absence of these disorders.
With the pressure of regulatory scrutiny and our duty to treat pain but contain abuse or diversion, clinicians often think that they must avoid being duped by those abusing prescription pain medications at all costs. Thus, although the differential diagnosis of aberrant drug-related behavior is complex, clinicians tend to simplify the assessment of this issue to either addiction or not addiction. It is important to note, however, that the clinician attempting to diagnose the meaning of aberrant drug-related behaviors during pain management may not be correct in the final assessment.
The anhydrous acid strontium oxalate Sr(HC2O4)⋅½(C2O4) was obtained by thermal decomposition of the hydrated acid strontium oxalate Sr(HC2O4)⋅½(C2O4)⋅H2O. This non-hygroscopic compound crystallizes in the space group P 21/c (No. 14) with unit cell parameters: a=0.796 61(7) nm, b=0.9205(1) nm, c=0.731 98(8) nm, and β=102.104(8)°. Final refinement of the X-ray powder data yielded RB=3.2% and Rwp=11.1% (background-corrected data). In this structure, Sr is eight-fold coordinated by O. These polyhedra are connected together by edge-sharing to form two-dimensional (2D) layers along the bc-plane, which means that there is an increased dimensionality from 1D to 2D with decreasing water content of the acid oxalates.
Ba0.5Sr0.5TiO(C2O4)2·5H2O, which is used as a precursor for Ba0.5Sr0.5TiO3 (BST), has been characterized by X-ray powder diffraction. In accordance with the known structure of BaTiO(C2O4)2·yH2O, the crystal system was found to be monoclinic with unit cell parameters: a=1.3965(1) nm, b=1.3811(2) nm, c=1.3306(2) nm, and β=92.15(1)°. The space group is P21/n, ρ=2.292(2) g cm−3, and Z=8.
The effects of plant density on the growth and yield of winter
oilseed rape
(Brassica napus) were
examined in a series of five multifactorial experiments at Rothamsted Experimental
Station between
1984 and 1989. Plant densities, manipulated by changing the seed rate and
row spacing, or because
of overwinter losses, ranged from 13·5 to 372 plants/m2.
Normalized yields for the multifactorial
plots increased with densities up to 50–60 plants/m2.
In very high density plots in 1987/88, yield
decreased as density increased >150 plants/m2. Plants
grown at high density had fewer pod-bearing
branches per plant but produced more branches/m2. Branch
dry matter (DM) per plant was
decreased by 42%, the number of fertile pods per plant and pod DM/plant
by 37%. There was no
effect of density on the number or DM of pods/m2. Over 74%
of the fertile pods were carried on the
terminal and uppermost branches of plants grown at high density in 1987/88
compared with only
34% in plants grown at low density in 1988/89. Seed DM/plant decreased
with increase in density
but seed size (1000-seed weight) increased. There was no effect of density
on seed glucosinolate or oil
contents.
The Dickson polynomial Dn, (x, a) of degree n is defined by denotes the greatest integer function. In particular, we define D0 (x, a) = 2 for all real x and a. By using Dickson polynomials we present new types of generalized Stirling numbers of the first and second kinds. Some basic properties of these numbers and a combinatorial application to the enumeration of functions on finite sets in terms of their range values is also given.