Coherent zero-state and pi-state in an exciton-polariton condensate array.

The effect of quantum statistics in quantum gases and liquids results in observable collective properties among many-particle systems. One prime example is Bose-Einstein condensation, whose onset in a quantum liquid leads to phenomena such as superfluidity and superconductivity. A Bose-Einstein condensate is generally defined as a macroscopic occupation of a single-particle quantum state, a phenomenon technically referred to as off-diagonal long-range order due to non-vanishing off-diagonal components of the single-particle density matrix. The wavefunction of the condensate is an order parameter whose phase is essential in characterizing the coherence and superfluid phenomena. The long-range spatial coherence leads to the existence of phase-locked multiple condensates in an array of superfluid helium, superconducting Josephson junctions or atomic Bose-Einstein condensates. Under certain circumstances, a quantum phase difference of pi is predicted to develop among weakly coupled Josephson junctions. Such a meta-stable pi-state was discovered in a weak link of superfluid 3He, which is characterized by a 'p-wave' order parameter. The possible existence of such a pi-state in weakly coupled atomic Bose-Einstein condensates has also been proposed, but remains undiscovered. Here we report the observation of spontaneous build-up of in-phase ('zero-state') and antiphase ('pi-state') 'superfluid' states in a solid-state system; an array of exciton-polariton condensates connected by weak periodic potential barriers within a semiconductor microcavity. These in-phase and antiphase states reflect the band structure of the one-dimensional polariton array and the dynamic characteristics of metastable exciton-polariton condensates.

Prevention and surveillance of public health risks during extended mass gatherings in rural areas: the experience of the Tamworth Country Music Festival, Australia.

OBJECTIVE: To describe and evaluate the public health response to the Tamworth Country Music Festival, an annual extended mass gathering in rural New South Wales, Australia; and to propose a framework for responding to similar rural mass gatherings. STUDY DESIGN: Process evaluation by direct observation, archival analysis and focus group discussion. METHODS: The various components of the public health response to the 2011 Tamworth Country Music Festival were actively recorded. An archival review of documentation from 2007 to 2010 was performed to provide context. A focus group was also conducted to discuss the evolution of the public health response and the consequences of public health involvement. RESULTS: Public health risks increased with increasing duration of the rural mass gathering. Major events held within the rural mass gathering further strained resources. The prevention, preparedness, response and recovery principles provided a useful framework for public health actions. Particular risks included inadequately trained food preparation volunteers functioning in poorly equipped temporary facilities, heat-related ailments and arboviral disease. CONCLUSION: Extended mass gatherings in rural areas pose particular public health challenges; surge capacity is limited and local infrastructure may be overwhelmed in the event of an acute incident or outbreak. There is value in proactive public health surveillance and monitoring. Annual mass gatherings provide opportunities for continual systems improvement. Early multi-agency planning can identify key risks and identify opportunities for partnership. Special consideration is required for major events within mass gatherings.

Pattern recognition of MRSI data shows regions of glioma growth that agree with DTI markers of brain tumor infiltration.

Gliomas are the most common primary brain tumors and the majority are highly malignant, with one of the worst prognoses for patients. Gliomas are characterized by invasive growth into normal brain tissue that makes complete surgical resection and accurate radiotherapy planning extremely difficult. We have performed independent component analysis of magnetic resonance spectroscopy imaging data from human gliomas to segment brain tissue into tumor core, tumor infiltration, and normal brain, with confirmation by diffusion tensor imaging analysis. Our data are consistent with previous studies that compared anomalies in isotropic and anisotropic diffusion images to determine regions of potential glioma infiltration. We show that coefficients of independent components can be used to create colored images for easy visual identification of regions of infiltrative tumor growth.

Pneumothorax in patients with acquired immunodeficiency syndrome.

Case histories of 25 consecutive patients with acquired immunodeficiency syndrome in whom pneumothorax developed from January 1985 to the present are reviewed. Spontaneous pneumothorax developed in 10 patients. All patients had a documented pulmonary infection. Four of 10 died, either of progressive respiratory failure or of concurrent infection. Patients with asymptomatic spontaneous pneumothorax can be safely observed. Patients with symptomatic pneumothorax should initially undergo tube thoracostomy. If an air leak persists, thoracotomy, stapling of blebs, and pleurodesis can be safely performed. Because of the prevalence of bilateral disease, a median sternotomy incision is recommended. Two patients underwent surgical treatment. Diffuse bullous disease associated with infiltration of lung parenchyma by Pneumocystis carinii pneumonia was identified in both. Both patients survived and were discharged. Patients whose pneumothorax developed while they were undergoing mechanical ventilation for respiratory failure induced by Pneumocystis carinii pneumonia had a 92.3% mortality rate. In all patients surviving for longer than 7 days after development of the initial pneumothorax, a contralateral pneumothorax later developed. Severe concurrent disease made the patients poor operative candidates. However, in the absence of concurrent illness, if a persistent large air leak is believed to contribute significantly to respiratory failure, surgical intervention may be indicated.

Exercise limitation in patients with polymyositis.

To examine the hypothesis that patients with inflammatory muscle disease have impairments in cardiac and/or pulmonary function that are masked by peripheral muscle weakness, complete PFTs, echo/Doppler studies and exercise testing were performed in 11 patients with polymyositis. Maximal inspiratory and expiratory pressures and expiratory flow rates were normal. One patient had evidence of restrictive lung disease; two had a reduced Dsb. Seven patients had evidence of pulmonary hypertension. Only three patients had normal aerobic capacity; VO2 max in the other 8 patients was 46 +/- 8 percent of predicted when they stopped exercising. Four patients had a normal O2 pulse; seven patients had a reduced O2 pulse while five of seven patients exceeded 85 percent of their target heart rate. We conclude that while asymptomatic impairments in pulmonary function are uncommon in polymyositis, the incidence of pulmonary hypertension is high, but symptoms may be masked by the peripheral muscle weakness.

Lysozyme-mediated de-chaining of Streptococcus mutans and its antibacterial significance in an acidic environment.

The ability of physiological amounts of lysozyme to de-chain two serotype c strains of Streptococcus mutans was determined. Both human and hen lysozymes were equally effective in chain breakage of S. mutans DPR and S. mutans DJR. De-chaining did not affect growth of cultures, but resulted in finely dispersed suspensions, at stationary phase, which were visibly different from untreated cultures. Less than 50 micrograms lysozyme per ml culture medium reduced chain length to virtually all diplococci and single cells, and this chain disruption increased total viable cell count. De-chaining required an active enzyme indicating that a degree of hydrolysis of the peptidoglycan occurred at the septae of the streptococci. De-chained S. mutans did not survive as well as streptococci of normal chain length when incubated under acidic conditions (pH 5.5), but gross cellular lysis was not apparent. The reduced aciduric property of the disrupted chains may have been due to a participation of autolysins or to a lethal triggered by the lysozyme-damaged peptidoglycan. De-chaining may be a mechanism by which lysozyme could regulate the levels of S. mutans in acidogenic plaque samples.

Noninvasive cardiovascular studies in patients with inflammatory myopathy.

The authors prospectively performed echocardiographic and Doppler studies on 13 patients with inflammatory myopathy to evaluate ventricular function, to assess valve morphology and function, and to obtain hemodynamic data. No patient had a reduction in left ventricular function or evidence of significant valvular disease. Hemodynamic assessment suggested evidence of pulmonary hypertension in 9 patients. They conclude that cardiomyopathy in association with inflammatory myopathy is unusual and that the suggestion of pulmonary hypertension is unexplained and merits further evaluation.

Rhetoric to practice: the challenge of collaboration of academe and industry.

Community health nursing is a complex practice that encompasses nurses working in many diverse settings. This article discusses the development of a project which focused on better preparation of students for potential employment in community settings. The formation of the working team and the development of the curriculum is outlined. A focus is given to the linking of primary health care principles in the teaching and facilitation of students within hospital and community settings. Comprehensive conclusions cannot be made yet from the project's preliminary findings. However, the process of collaboration has demonstrated several issues. These will have an impact on everyone who has been part of this project, and the issues are discussed in this article. The article provides an overview of the first year of collaboration of a 4-year project.

Health promotion--a focus for hospitals.

A hospital is in a unique position, both as a service provider and an employer, to provide a focus for disease prevention and health maintenance based on a greater understanding of the relationship between social and physical environment and lifestyle factors on health. Developing hospitals to become a resource for health instead of merely another link in the sick-care chain requires a substantial change in philosophy, management and practice. Reaching out into the community, establishing new and different relationships with consumers, and creating an environment conducive to healthy behaviour are only some of the changes necessary to reflect a health promotion focus. This paper discusses the experiences of establishing, developing and maintaining health promotion services at Flinders Medical Centre.

Bridging the gap. Community partnerships in nursing education: advancing primary health care in practice.

An innovative approach to nursing education was piloted by the School of Nursing at Flinders University and Noarlunga Health Services, a generic community health service, in Adelaide, South Australia. The approach, encapsulated in the four-year Community Enrichment Project (CEP), focused on Primary Health Care (PHC) and nursing practice. The CEP developed curriculum and organised student placements, which promoted understanding of PHC in a way that integrated acute and community sectors. This paper considers the impact of splitting the students' third year final practicum, of seven weeks, between acute and community placements. Integral to the overall outcome of the project was the community agencies' cooperation in accepting students for longer clinical placements than had previously been the norm. This resulted in students being engaged in activities and projects in diverse areas. The students were aided in linking PHC theory to practice by the CEP team members who mentored them throughout these placements. Outcomes demonstrated the ability of students to integrate PHC theory to practice, across a variety of health settings. Students moved from a position of little knowledge or understanding of PHC, to an integrated knowledge of PHC principles and the relationship to enhanced nursing practice.

Curriculum collaboration and the Ottawa Charter: a nursing initiative.

The World Health Organization (WHO) and the International Council of Nurses (ICN) have been consistent in their call for nurses to be involved with Primary Health Care (PHC). This paper will demonstrate how an innovative partnership between the School of Nursing, Flinders University of South Australia (FUSA) and Noarlunga Health Services (NHS) has been instrumental in developing an undergraduate nursing curriculum which has the potential to guide future nursing practice. The Community Enrichment Project (CEP) has been an example of health promotion in practice and demonstrates how a PHC philosophy can permeate all levels of health care.

Innovations in community health nursing: examples from practice.

The Ottawa Charter for Health Promotion is cited internationally as an appropriate conceptual framework for healthcare service delivery yet the literature reveals minimal evidence of nursing services interpreting and applying the Ottawa Charter strategies into nursing practice. Nurses with the community services of Noarlunga Health Services and the Drug and Alcohol Services Council of South Australia, however, do use the strategies to plan and implement their services. The Ottawa Charter strategies of developing personal skills; creating supportive environments; strengthening community action; building healthy public policy; and re-orienting services in the interest of health can be used as a tool to assist nurses to identify the purpose of their interventions and select a comprehensive range of nursing actions which address the needs of individuals while acknowledging the broader determinants of health. This article presents a nursing analysis of the Charter and provides examples of how the strategies are used to influence nursing practice in both organizations. The examples provided from the two different nursing services also demonstrate the adaptability and relevance of the strategies to diverse community nursing practice settings.

Intramedullary nailing of tibial diaphyseal fractures in adolescents with open physes.

An analysis of 36 adolescent patients who presented with tibial diaphyseal fractures and open tibial physes has been undertaken. All patients were treated by reamed intramedullary nailing using a hollow, slotted nail. They were examined clinically and radiologically for late evidence of the effects of premature physeal closure secondary to nailing damage, but none were found. The speed of union in Tscherne C0 and C1 fractures in 13-16-year-old patients is highlighted and shown to be considerably faster than in adult patients. The speed of union in Tscherne C2 fractures is similar in adolescents and adults. The relatively high incidence of compartment syndrome in this age group is noted. Intramedullary nailing of tibial diaphyseal fractures in adolescents with open physes, using a slotted nail, appears to be safe and does not cause late growth problems.

Pharmacologic therapy of low output syndromes after cardiac surgery.

With the advancement of surgical techniques and myocardial protection we can expect that patients previously felt to be inoperable because of poor ventricular function will be surgical candidates. This group of patients will on occasion develop severe left ventricular dysfunction in the peri-operative period. Optimum management in this setting will require acquisition of haemodynamic data, assessment of ventricular loading conditions and inotropic state and the selection of appropriate drug therapy. Drugs are available with specific haemodynamic profiles and therapy is enhanced by matching the abnormal haemodynamics of patients with an appropriate therapeutic agent. If the patient fails to respond quickly to pharmacotherapy, consideration should be directed toward use of an intra-aortic balloon pump.

Left ventricular outflow obstruction by a mitral valve prosthesis: Doppler ultrasound and cardiac catheterization findings.

Left ventricular outflow tract obstruction by a mitral valve prosthesis was noted several years following surgery when symptoms of congestive heart failure occurred. The diagnosis was made using two-dimensional echocardiography and Doppler techniques and confirmed at heart catheterization, using micromanometer tipped catheters.

Strength and endurance in the therapeutic evaluation of prednisolone-treated MDX mice.

The dystrophin-deficient, X-linked dystrophic mouse (mdx) was used to evaluate the efficacy of prednisolone treatment. A test protocol was used to take advantage of the quantifiable weakness and disability as well as molecular genetic defect shared with the X-linked Duchenne muscular dystrophy (DMD). Whole-body weakness and fatigue were determined by non-invasive force-transducer physiographic and variable-speed treadmill techniques, respectively. Other measurements included hind-limb muscle protein, calcium, and histomorphology. Subcutaneously-administered prednisolone elicited significant improvements in whole body strength throughout a two-month test period. Increases in strength were also accompanied by measurable increments in running endurance. In fact, prednisolone treatment appeared to protect mdx mice from the stressful effect of continuous running as determined by strength and muscle fiber diameter. Test results from this study support the limited therapeutic benefit observed previously in DMD patients treated with the glucocorticoid.