Femtosecond soliton pulse delivery at 800nm wavelength in hollow-core photonic bandgap fibers

We describe delivery of femtosecond solitons at 800nm wavelength over five meters of hollow-core photonic bandgap fiber. The output pulses had a length of less than 300fs and an output pulse energy of around 65nJ, and were almost bandwidth limited. Numerical modeling shows that the nonlinear phase shift is determined by both the nonlinearity of air and by the overlap of the guided mode with the glass.

'Part of the family': sources of job satisfaction amongst a group of community-based dementia care workers

The development of community-based services for people with dementia brings new challenges for health and social care providers, not least that of sustaining an enthusiastic workforce who are motivated to provide care and support under potentially isolating and difficult conditions. The present paper, based on interview data gathered from a group of community-based dementia care workers, seeks to identify their sources of job satisfaction and reward. Interviews were conducted with seven workers at two points in time and the data were analysed using a case by theme matrix approach. The results indicate that there were high levels of job satisfaction amongst the group, which were enhanced by several factors, including: good organisational support; day-to-day autonomy; the ability to maintain relationships with people with dementia and their families; and staffs' feelings of contributing to and improving the status and quality of life of people with dementia. Implications for workforce development are briefly considered.

Designer femtosecond pulses using adaptive optics

We describe a femtosecond pulse shaper using a deformable membrane mirror. The pulses are measured with a real time second-harmonic-generation frequency-resolved optical gating system. Pulse shapes are modified according to a prescribed spectral phase. Accurate spectral phase design as well as pulse intensity modulation was achieved by using negative feedback mirror-surface control. Convergence to the chosen spectral phase design was typically achieved within several seconds.

Refeeding syndrome: effective and safe treatment with Phosphates Polyfusor

BACKGROUND

Severe hypophosphataemia associated with refeeding syndrome requires treatment with intravenous phosphate to prevent potentially life-threatening complications. However, evidence for replacement regimens is limited and current regimens are complex and replace phosphate inadequately.

AIM

To assess the effectiveness and safety of 50 mmol intravenous phosphate infusion, given as a 'Phosphates Polyfusor', for the treatment of severe hypophosphataemia in refeeding syndrome.

METHODS

Patients with refeeding syndrome and normal renal function received a Phosphates Polyfusor infusion for the treatment of severe hypophosphataemia (< 0.50 mmol/L). The outcome measures were serial serum phosphate, creatinine and calcium concentrations for 4 days following phosphate infusion and adverse events.

RESULTS

Over 2 years, 30 patients were treated. Following treatment, 37% of cases had a normal serum phosphate concentration and 73% had a serum phosphate concentration of > 0.5 mmol/L within 24 h. Ten patients required more than one Phosphates Polyfusor infusion. Within 72 h, 93% of cases had achieved a serum phosphate concentration of > or = 0.50 mmol/L. No patient developed renal failure. Three episodes of transient mild hyperphosphataemia were recorded. Four patients developed mild hypocalcaemia.

CONCLUSIONS

This is the largest published series of the use of intravenous phosphate for the treatment of severe hypophosphataemia (< 0.50 mmol/L), and is the most effective regimen described. All patients had refeeding syndrome and were managed on general wards.

Gastroschisis: A sixteen-year review

PURPOSE

The aim of this study was to examine the incidence of gastroschisis in Saskatchewan over a 16-year period and identify risk factors associated with mortality.

METHODS

Information was obtained by retrospective review of all infant charts at the only 2 provincial neonatal intensive care centers from January 1985 through December 2000. Factors recorded were gestational age, birth weight, gender, Apgar score, time to operation, method of closure, time to attain full feedings, presence of sepsis, and length of hospital stay. Live birth data for the province was obtained, and the incidence per 10,000 live births for 3 time intervals was calculated. Analysis was performed with mortality as the dependent variable.

RESULTS

Seventy-one infants were identified. Overall survival rate was 93% (66 of 71). During the 3 time intervals examined, the incidence of gastroschisis per 10,000 live births increased from 1.85 in 1985 to 1990 to 3.66 in 1991 to 1995 to 4.06 in 1996 to 2000. The analysis found that intestinal atresia P =.009, OR = 18.3 (95%CI: 2.457-136) and intestinal necrosis P =.050, OR = 10.33 (95%CI: 1.32-80.68) were significantly associated with mortality.

CONCLUSIONS

The incidence of gastroschisis is increasing. Intestinal atresia and the development of intestinal necrosis were associated with poor outcome. Patients who had these complications all had short bowel, and full feedings could not be established. They required continuation of total parenteral nutrition and experienced episodes of sepsis.

The perceived expressed emotion in staff scale

Recent research has highlighted the role of expressed emotion by ward staff in determining the well-being of psychiatric inpatients. Existing methods of assessing staff expressed emotion involve standardized interviews and are expensive and time-consuming. We report the development of a questionnaire measure of expressed emotion in staff as perceived by patients. In study 1, factor analysis of items administered to patients in a variety of settings led to the development of a questionnaire with three subscales: supportiveness, criticism and intrusiveness. In study 2, the test-retest reliability of the questionnaire was found to be adequate, and some evidence of concurrent validity for the scale was obtained against expressed emotion rated from staff speech samples. In study 3, the scale was shown to have good concurrent validity against the ward atmosphere scale, and scores were found to be independent of insight or experience of admission to hospital. The perceived expressed emotion in staff scale is a convenient measure, which may have utility for both research and clinical purposes.

Effects of a wheelchair-mounted rigid pelvic stabilizer on caregiver assistance for children with cerebral palsy

A within-subjects repeated measures (A1, B, A2) design was used to study the impact of a rigid pelvic stabilizer (RPS) compared with a traditional lap belt on the caregiver assistance requirements of six children with cerebral palsy as they completed functional tasks from their wheelchair seating system. Study participants wore a lap belt during the 3-week baseline phases (A1 and A2). The RPS was used during the 5-week intervention phase (B). At baseline, each child and parent identified five bimanual or reaching tasks with which the child had difficulty. Using a six-point scale, each parent (caregiver) rated the degree of assistance the child required to do each task. Parents also maintained a log, recording how many times the child was repositioned daily. The RPS appeared to impact directly on reducing caregiver assistance for 30% of the tasks, as the need for assistance was less during phase B when the RPS was used and was greater during phases A1 and A2 when the lap belt was worn. Five children required repositioning less often during phase B than during the A phases. The RPS reduced the child's need for caregiver assistance for some bimanual and reaching tasks as well as for repositioning.

Effects of automatic cluster remover settings on average milking duration, milk flow, and milk yield

A crossover study design was used in five commercial dairy herds to study the effect of altering the switch point settings for automatic cluster remover units on the average duration of unit attachment, milk flow, and milk yield. Automatic cluster remover switch point settings were alternated, for 1-wk periods, between 0.50 and 0.64 kg/min (1.1 and 1.4 lb/min) in one herd and between 0.73 and 0.82 kg/min (1.6 and 1.8 lb/min) in the four remaining herds. Parlor data were captured at 329 separate milking sessions (range 39 to 92 per herd), representing 239,393 individual cow milkings. While increasing the automatic cluster remover switch point setting was not associated with a change in average milking duration in one herd, it had the effect of significantly reducing the average milking duration by between 10.2 and 15.6 s per cow in the remaining four herds. Milk flow was significantly increased at higher switch point settings for all five herds. Higher automatic cluster remover switch point settings did not have a negative effect on milk yield in any of the herds studied and, in fact, were associated with increased milk yield in two of the five herds. Decreasing milking duration while either maintaining or increasing the volume of milk harvested should ultimately lead to improved milking efficiency and parlor performance. Modifying systems to increase automatic cluster remover switch point settings offers an important potential opportunity to increase parlor efficiency in commercial dairy herds.

Airway inflammation, basement membrane thickening and bronchial hyperresponsiveness in asthma

BACKGROUND

There are few data in asthma relating airway physiology, inflammation and remodelling and the relative effects of inhaled corticosteroid (ICS) treatment on these parameters. A study of the relationships between spirometric indices, airway inflammation, airway remodelling, and bronchial hyperreactivity (BHR) before and after treatment with high dose inhaled fluticasone propionate (FP 750 microg bd) was performed in a group of patients with relatively mild but symptomatic asthma.

METHODS

A double blind, randomised, placebo controlled, parallel group study of inhaled FP was performed in 35 asthmatic patients. Bronchoalveolar lavage (BAL) and airway biopsy studies were carried out at baseline and after 3 and 12 months of treatment. Twenty two normal healthy non-asthmatic subjects acted as controls.

RESULTS

BAL fluid eosinophils, mast cells, and epithelial cells were significantly higher in asthmatic patients than in controls at baseline (p<0.01). Subepithelial reticular basement membrane (rbm) thickness was variable, but overall was increased in asthmatic patients compared with controls (p<0.01). Multiple regression analysis explained 40% of the variability in BHR, 21% related to rbm thickness, 11% to BAL epithelial cells, and 8% to BAL eosinophils. The longitudinal data corroborated the cross sectional model. Forced expiratory volume in 1 second improved after 3 months of treatment with FP with no further improvement at 12 months. PD(20) improved throughout the study. BAL inflammatory cells decreased following 3 months of treatment with no further improvement at 12 months (p<0.05 v placebo). Rbm thickness decreased in the FP group, but only after 12 months of treatment (mean change -1.9, 95% CI -3 to -0.7 microm; p<0.01 v. baseline, p<0.05 v. placebo). A third of the improvement in BHR with FP was associated with early changes in inflammation, but the more progressive and larger improvement was associated with the later improvement in airway remodelling.

CONCLUSION

Physiology, airway inflammation and remodelling in asthma are interrelated and improve with ICS. Changes are not temporally concordant, with prolonged treatment necessary for maximal benefit in remodelling and PD(20). Determining the appropriate dose of inhaled steroids only by reference to symptoms and lung function, as specified in current international guidelines, and even against indices of inflammation may be over simplistic. The results of this study support the need for early and long term intervention with ICS, even in patients with relatively mild asthma.

Growth processes in teeth distinguish modern humans from Homo erectus and earlier hominins

A modern human-like sequence of dental development, as a proxy for the pace of life history, is regarded as one of the diagnostic hallmarks of our own genus Homo. Brain size, age at first reproduction, lifespan and other life-history traits correlate tightly with dental development. Here we report differences in enamel growth that show the earliest fossils attributed to Homo do not resemble modern humans in their development. We used daily incremental markings in enamel to calculate rates of enamel formation in 13 fossil hominins and identified differences in this key determinant of tooth formation time. Neither australopiths nor fossils currently attributed to early Homo shared the slow trajectory of enamel growth typical of modern humans; rather, both resembled modern and fossil African apes. We then reconstructed tooth formation times in australopiths, in the approximately 1.5-Myr-old Homo erectus skeleton from Nariokotome, Kenya, and in another Homo erectus specimen, Sangiran S7-37 from Java. These times were shorter than those in modern humans. It therefore seems likely that truly modern dental development emerged relatively late in human evolution.

Bronchoalveolar lavage macrophage and lymphocyte phenotypes in lung transplant recipients

Recent publications have demonstrated potentially pathologic changes in bronchoalveolar lavage (BAL) from clinically stable lung transplant recipients (SLTRs), but there are few available data on alveolar macrophages (AMs). We formulated the hypothesis that changes in BAL AM and lymphocyte phenotypes would be apparent even in SLTRs.A cross-sectional study using a standardized 3 x 60 ml BAL, investigating lymphocyte and AM phenotypes in 19 SLTRs, 5 subjects with bronchiolitis obliterans syndrome (BOS) and 18 normal control volunteers. BAL lymphocyte and AM markers were assessed using flow cytometry. We confirmed a significant elevation of neutrophils in all lung transplant recipients with a more marked elevation in the BOS subjects. Flow-cytometric analysis showed increased numbers of natural killer (NK; CD56/CD16-positive) cells, increased CD11b- and CD11c-positive CD3 lymphocytes, increased CD8-positive lymphocytes and increased HLA-DR expression in CD8 cells from the lung transplant recipients, when compared with normals (p <.005). In contrast, the expression of a number of AM surface markers, associated with a range of host defense functions against bacteria, fungi and viruses (CD11a, CD11b, CD11c, HLA-DR, CD14), was lower in both SLTRs and those with BOS (p <.05). These novel findings are consistent with complex lymphocyte and macrophage changes that may result from clinically silent infection, partially suppressed rejection, or both.

Iron overload and nitric oxide-derived oxidative stress following lung transplantation

BACKGROUND

Reactive oxygen species (ROS) may contribute to airway injury and the development of the bronchiolitis obliterans syndrome (BOS) following lung transplantation (LT). Chemically active iron released from ferritin stores and nitric oxide (NO)-derived radicals may add to the oxidative burden.

METHODS

We determined the concentrations of ferritin and the aqueous NO derivative nitrite (NO2(-)) within bronchoalveolar lavage fluid (BALF) of 14 stable LT recipients (ST) and 7 subjects with BOS and 21 normal controls. We also assessed the relationship between BALF ferritin and hemosiderin-laden macrophages (HLMs) using a hemosiderin score (HS) and determined BALF albumin concentration as a marker of microvascular leakage.

RESULTS

BALF ferritin concentrations and HSs were significantly elevated in LT recipients overall compared with normal controls (p < 0.05). BALF NO2(-) levels were elevated in BOS subjects and STs compared with normal controls (p = 0.002 and p = 0.09, respectively), but there was no difference between transplant groups. BALF albumin concentrations were elevated in BOS patients compared with normal controls (p = 0.02) and ST (p = 0.05), but there was no difference between STs and controls. There was a significant relationship between BALF ferritin concentration and HS in LT recipients overall (r(s) = 0.7, p < 0.001). In BOS subjects, but not ST, BALF ferritin was significantly related to BALF albumin (r(s) = 0.8, p = 0.05) and there was a weak relationship with NO2(-) concentration (r(s) = 0.6, p = 0.1). BALF NO2(-) was strongly related to BALF % neutrophils in BOS subjects (r(s) = 0.9, p < 0.01), but there was no such relationship in STs.

CONCLUSIONS

Our findings suggest that the allograft could be subject to significant iron-generated oxidative stress, which may be exacerbated by NO and neutrophil-derived ROS, particularly in BOS. Microvascular leakage may be a feature of established chronic rejection, which potentiates the iron overload and contributes to further airway damage and remodeling.

Introduction to NMR of proteins

This unit aims to overview the application of NMR spectroscopy to proteins. It is not intended to provide an exhaustive "how to" guide, but rather to give a flavor of both well-established and emerging NMR techniques used in the elucidation of protein structure. It starts with a brief introduction to the basic principles of NMR and the information provided by this technique, and goes on to discuss the instrumentation involved, spectral assignment methods for small and large proteins, and the utility of other spin active nuclei (e.g., (13)C and (15)N) to aid assignment of the latter.

Normally suppressing CD40 coregulatory signals delivered by airway macrophages to TH2 lymphocytes are defective in patients with atopic asthma

BACKGROUND

We have previously shown that airway macrophages (AMs) from atopic nonasthmatic subjects, but not atopic asthmatic subjects, inhibit T-cell IL-5 production during an allergen-dependent interaction. However, the mechanisms responsible for the IL-5-modulating effect of the AMs are less clear.

OBJECTIVES

The aim of the present study was to define the roles of B7 and CD40 costimulatory signals delivered by AMs in regulating T-cell IL-5 responses in an allergen-stimulated coculture system.

METHODS

Peripheral blood CD4(+) T cells and AMs were cocultured under different conditions.

RESULTS

Compared with those from well-matched atopic nonasthmatic subjects, AMs from atopic asthmatic subjects demonstrated a significantly lower expression of B7-1 and CD40, but not B7-2 and HLA-DR, after either fresh isolation or coculture with allergen-reactive CD4(+) T cells. Lower IL-12 production by the AMs from asthmatic subjects was also observed under the same conditions. Allergen-related T-cell IFN-gamma and IL-5 production was inhibited by the addition of either neutralizing B7-1 or B7-2 antibody to the cocultures in both atopic groups. In contrast, IL-5 production was significantly increased by the addition of blocking CD40 antibody, whereas IL-12 production by the AMs was inhibited. Anti-IL-12 mAb enhanced IL-5 production in the cocultures from atopic nonasthmatic subjects, whereas a dose-dependent suppressive effect of recombinant human IL-12 on IL-5 production was seen in atopic asthmatic subjects.

CONCLUSION

In this coculture model system, lower IL-12 production by AMs and higher IL-5 production by CD4(+) T cells in atopic asthmatic subjects compared with that found in atopic nonasthmatic subjects are related to the lower expression of CD40 rather than B7-1 signals on the AMs from these patients.

The ICAROS registry of carotid artery stenting. Imaging in Carotid Angioplasties and Risk of Stroke

ICAROS (Imaging in Carotid Angioplasties and Risk Of Stroke) is a multicenter international registry of carotid artery stenting designed to determine the criteria for identifying patients at higher or lower risk of periprocedural stroke and restenosis at 1 year. The aim of the registry is to improve patient selection and consequently reduce the risk of cerebral embolization during carotid stenting. The registry is open to all interventionists performing carotid stenting, and the participants are free to apply their own endovascular techniques and devices, including cerebral protection mechanisms. All cerebral ischemic events following the procedure will be reported. Follow-up surveillance to 1 year will include periodic duplex scanning and neurological examinations. Echographic plaque images will be standardized for comparison, processed for echodensity, and analyzed by computer at the Registry Center. Correlation will be investigated between the echographic index (gray-scale median) and the risk of embolism and outcome of carotid stenting.

Technical knowledge and the mental universe of Manchester's early cotton manufacturers

Through the reinterpretation of evidence long available but still underutilized, the authors explore the role of mechanical and technical knowledge in the making of the industrial revolution in cotton. Traditionally, science — understood in eighteenth-century Britain to be largely, although not exclusively, the science of mechanics — has been seen to have little to do with spinning machines and power weaving. But the steam engine required a degree of technical knowledge which the leaders in Manchester cotton manufacturing possessed. Furthermore, this study of Manchester in the period from 1790 to 1820 focuses on the urban setting as a locus of innovation and the chapel life of Unitarians as providing a site for the inculcation of religious values compatible with an ethic for both entrepreneurs and workers. The article contributes to the growing (and often neo-Weberian) cultural history of the first Industrial Revolution. M’Connell and Kennedy led the Manchester cotton industry for over two decades and they stamped their values and knowledge base into the community through their avid participation in scientific societies and chapel life. Their manuscripts at the John Rylands Library, Deansgale, Manchester form the core of this article.

Evidence that ceramide mediates the ability of tumor necrosis factor to modulate primitive human hematopoietic cell fates

In this study, it is shown that short-term exposure of normal human marrow CD34(+)CD38(-) cells to low concentrations of tumor necrosis factor (TNF) in the presence of 100 ng/mL Flt3 ligand and Steel factor and 20 ng/mL interleukin-3 (IL-3), IL-6, and granulocyte colony-stimulating factor, in either bulk or single-cell serum-free cultures, markedly reduces their ability subsequently to generate colony-forming cells (CFCs) in 6-week stromal cell-containing long-term cultures without affecting their viability, mitogenic response, or short-term ability to produce CFCs. A similar differential effect on the functional attributes of CD34(+)CD38(-) cells was seen when C2- or C6-ceramide, but not dihydro-C2-ceramide (an inactive analog of ceramide), was substituted for TNF. The addition of D-erythro-MAPP (a specific inhibitor of intracellular ceramide degradation) enhanced the ability of TNF to selectively eliminate long-term culture-initiating cell (LTC-IC) activity. These findings indicate that TNF can directly modulate the ability of CD34(+)CD38(-) cells to maintain their LTC-IC function at doses below those required to initiate apoptosis, cell cycle arrest, or both, and they suggest that this may be mediated by the TNF-induced generation of intracellular ceramide. Identification of a signaling intermediate that can influence primitive hematopoietic cell fate decisions offers a new approach to the investigation of signaling mechanisms in normal stem cell populations and to how these may be altered in leukemic cells.

Management and treatment perceptions among young adults with asthma in Melbourne: the Australian experience from the European Community Respiratory Health Survey

OBJECTIVES

As part of the European Community Respiratory Health Survey (ECRHS) in 1992-1993 we assessed management practices and treatment perceptions among young asthmatic adults in Melbourne, Australia.

METHODOLOGY

We conducted a postal questionnaire survey of 4500 randomly selected adults (aged 20-44 years), drawn from three electoral districts, of whom 3200 (71%) subjects responded. A randomly selected sample of 1642 respondents, 'enriched' by a further 433 symptomatic subjects, was invited to complete a second phase respiratory questionnaire.

RESULTS

The questionnaire was completed by 757 subjects who underwent laboratory testing. A further 119 subjects who were unable to attend the laboratory completed an identical questionnaire by telephone interview (42% response rate). In the second phase, 16% of subjects reported 'current asthma' (group I) as defined by physician confirmation and a recent attack (within 1 year), 10% had confirmed asthma but reported no recent attack (group II) and 74% did not have asthma (group III). Inhaled corticosteroid use was significantly higher in group I than in group II subjects (45% vs 24%, P<0.01), but only 11% of asthmatic subjects overall reported daily prophylactic use. Regular treatment in any form was considered to be 'bad' by 65% of asthmatic subjects and only 43% took medication as prescribed all of the time.

CONCLUSION

Despite national education campaigns, the majority of young asthmatic adults in Melbourne did not adhere to prescribed treatment, but continued to rely upon beta2-agonists alone with neglect of regular inhaled corticosteroid which has probably contributed to Australia's continued high asthma morbidity and mortality rates.

Prevalence of HIV among pregnant women in Dundee 1988-1997: evidence to gauge the effectiveness of HIV prevention measures

OBJECTIVES

During November 1988-July 1990, an HIV prevalence survey of pregnant women in Dundee, which used a combined voluntary diagnostic testing and voluntary unlinked anonymous approach, revealed a rate of 0.3%, the highest recorded prevalence among such a population in the U.K. at the time. To determine if, and why, any changes in HIV prevalence had occurred during the early to mid 1990s, further studies were conducted.

METHODS

During January 1993-December 1997, antenatal patients of, and women undergoing therapeutic termination of pregnancy at, Ninewells Hospital, Dundee, were offered a diagnostic HIV antibody test. For those declining, residual sera from rubella specimens were tested for HIV antibodies using an unlinked anonymous approach which did not necessitate the securement of informed consent. Information about injecting drug use was obtained from all women and linked to their HIV test results.

RESULTS

For all pregnant women, a significant decline in HIV prevalence (P<0.05) from 0.3% (19/6228) during 1988-1990 to 0.12% (22/17899) during 1993-1997 was observed. For those who injected drugs, prevalence decreased significantly (P<0.05) from 27.5% (11/40) to 7% (6/85), while among women who had never injected drugs prevalence decreased slightly, but not significantly (P>0.05), from 0.13% (8/6188) to 0.09% (16/17814).Prevalence in the non-injectors who reported no sexual intercourse with an injector was low at 0.04% (8/17682) during 1993-1997. No significant trends in HIV prevalence were seen over the 5 years up to 1997.

CONCLUSION

The decline in HIV prevalence among pregnant women in Dundee during the early to mid-1990s can be explained predominantly by the control of HIV transmission among the city's injectors, and from them to the wider heterosexual population. It is likely that interventions designed to reduce needle/syringe sharing among injectors have been successful. It is imperative that the preventive effort is not allowed to be weakened.