Achievement of Target Gain Larger than Unity in an Inertial Fusion Experiment

On December 5, 2022, an indirect drive fusion implosion on the National Ignition Facility (NIF) achieved a target gain G_{target} of 1.5. This is the first laboratory demonstration of exceeding "scientific breakeven" (or G_{target}>1) where 2.05 MJ of 351 nm laser light produced 3.1 MJ of total fusion yield, a result which significantly exceeds the Lawson criterion for fusion ignition as reported in a previous NIF implosion [H. Abu-Shawareb et al. (Indirect Drive ICF Collaboration), Phys. Rev. Lett. 129, 075001 (2022)PRLTAO0031-900710.1103/PhysRevLett.129.075001]. This achievement is the culmination of more than five decades of research and gives proof that laboratory fusion, based on fundamental physics principles, is possible. This Letter reports on the target, laser, design, and experimental advancements that led to this result.

Lawson Criterion for Ignition Exceeded in an Inertial Fusion Experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion.

Nurses' perspectives on whether medical aid in dying should be accessible to incompetent patients with dementia: findings from a survey conducted in Quebec, Canada

We conducted a survey in a random sample of 514 Quebec nurses caring for the elderly to assess their attitudes towards extending medical aid in dying to incompetent patients and to explore associated factors. Attitudes were measured using clinical vignettes featuring a hypothetical patient with Alzheimer disease. Vignettes varied according to the stage of the disease (advanced or terminal) and the presence or absence of a written request. Of the 291 respondents, 83.5% agreed with the current legislation that allows physicians to administer aid in dying to competent patients who are at the end of life and suffer unbearably. A similar proportion (83%, p = 0.871) were in favor of extending medical aid in dying to incompetent patients who are at the terminal stage of Alzheimer disease, show signs of distress, and have made a written request before losing capacity.

Progressive facial asymmetry resulting from condylar osteochondroma - A case report detailing the resection, subsequent orthognathic intervention and custom joint replacement

We discuss a 37 year old male - who presented with marked facial asymmetry and signs/symptoms suggestive of condylar hyperplasia. Imaging confirmed a large exophytic growth arising from the right mandibular condylar head. Treatment included tumour resection, orthognathic intervention and total joint replacement. The clinical presentation, pathology and treatment, along with a brief discussion are described in this report.

Pereira's attack on legalizing euthanasia or assisted suicide: smoke and mirrors

OBJECTIVE

To review the empirical claims made in: Pereira J. Legalizing euthanasia or assisted suicide: the illusion of safeguards and controls. Curr Oncol 2011;18:e38-45.

DESIGN

We collected all of the empirical claims made by Jose Pereira in "Legalizing euthanasia or assisted suicide: the illusion of safeguards and controls." We then collected all reference sources provided for those claims. We compared the claims with the sources (where sources were provided) and evaluated the level of support, if any, the sources provide for the claims. We also reviewed other available literature to assess the veracity of the empirical claims made in the paper. We then wrote the present paper using examples from the review.

RESULTS

Pereira makes a number of factual statements without providing any sources. Pereira also makes a number of factual statements with sources, where the sources do not, in fact, provide support for the statements he made. Pereira also makes a number of false statements about the law and practice in jurisdictions that have legalized euthanasia or assisted suicide.

CONCLUSIONS

Pereira's conclusions are not supported by the evidence he provided. His paper should not be given any credence in the public policy debate about the legal status of assisted suicide and euthanasia in Canada and around the world.

Natural options for the management of hyperpigmentation

Facial hyperpigmented disorders are a common complaint in the adult population of all races. First-line topical treatments are usually hydroquinone or topical retinoids, which can cause irritant reactions. The need for better tolerated, yet effective, skin lightening agents that could be utilized by a wider population has led to the investigation of several potential botanical/natural compounds. There are currently many topical cosmetic formulations claiming skin depigmenting effects. A few of the ingredients (e.g. soy) are supported not only by in vitro results but also by a body of controlled clinical efficacy studies; other ingredients, instead, are backed mostly by in vitro data and a few small uncontrolled clinical studies. In this review, we describe the most common natural ingredients used for skin depigmentation and their major published studies: soy, licorice extracts, kojic acid, arbutin, niacinamide, N-acetylglucosamine, COFFEEBERRY(™) and green tea.

Use of high-frequency ultrasound in the assessment of injectable dermal fillers

BACKGROUND

The use of dermal fillers for enhancing lips and reducing wrinkles is currently one of the fastest growing sectors of the cosmetic surgery market. There are numerous fillers available, some are synthetic others are isolated from biological material. Once injected the fillers have a varied lifespan ranging from months to years depending upon the material, site of injection and individual response. Current assessment techniques of filler performance are mostly limited to evaluations of the skin surface topography, and not to what is happening to the filler beneath the skin surface. The aim of this work was to see if high-frequency ultrasound could be used to image and measure filler dimensions in situ.

METHOD

This was a pilot study of six healthy female volunteers aged 36-53 visiting the surgical outpatients department of a hospital in Glasgow. Volunteers had been injected with filler material into their upper lip 6 months before the visit. The patients all had their upper lip scanned using high-frequency ultrasound. The subsequent images were then assessed using the scanner software to assess the dimensions of the filler.

RESULTS

The filler material was clearly visible with the ultrasound and subsequently measurable in each scan. Each scan procedure was completed within a short time period meaning quantitative data could be acquired with minimum trauma to the volunteer. The scan images and data also provided valuable information for the volunteers and reinforced their perception of the fillers effect on their features.

CONCLUSIONS

High-frequency ultrasound scanning provides a non-invasive, convenient and rapid technique for the assessment of filler performance. This pilot study produced three valuable pieces of information: The ultrasound can image the filler material from which quantitative measurements can be made. The technique is rapid and cost effective ...This investigation helped to reinforce the volunteer's perception of the filler effect.

Family override of valid donor consent to postmortem donation: issues in law and practice

In 2005, 3974 Canadians were on waiting lists for organ transplants and 275 patients died while waiting. Canada's organ shortage has led to calls for changes to Canada's organ donation system and its legal framework. Herein we examine an issue in which law reform could both increase the number of available organs and better align practice with respect for autonomy, a core value underpinning the Canadian legal system: the issue of family overrides of a valid donor consent to postmortem donation. That is, we examine what should happen when an individual consented to postmortem donation but the family would like to override that consent. First, we examine the requirements for valid donor consent. Second, we consider the legal status of family overrides of valid donor consent in relation to postmortem donation. Third, we describe the available data with regard to the practice of permitting families to override valid donor consent and discuss the possible reasons for this practice. Finally, we describe and defend the desired results with respect to law reform and describe the actions needed to realize these results.

Maternal psychosocial well-being in pregnancy and breastfeeding duration

AIM

An increased duration of breastfeeding has many advantages for the child and mother. However, little research to date has investigated the influence of maternal psychosocial well-being during pregnancy on the duration of breastfeeding. This study aimed to examine whether experience of life stress events, social contact/support in pregnancy and postpartum emotional disturbance had an effect on breastfeeding duration.

METHODS

Using data from the Western Australian Pregnancy Cohort Study for 2420 women followed from 18 weeks gestation, we analyzed prevalent breastfeeding for 4 months or longer and its association with maternal psychosocial and socio-demographic factors in pregnancy, using multivariable logistic regressions.

RESULTS

Experience of stressful life events during pregnancy increased the odds for the early cessation of prevalent breastfeeding (OR 1.34, p < 0.05, 95% CI 1.04-1.71) independent of maternal socio-demographic characteristics and biomedical factors. Stress events associated with separation or divorce, financial problems and residential moves in pregnancy were important predictors for a shorter duration of prevalent breastfeeding.

CONCLUSION

Experience of stressful life events during pregnancy increased the odds for the early cessation of prevalent breastfeeding. Interventions that move beyond hospital-based antenatal care to address the causes of maternal stress in pregnancy and socioeconomic disparities between women are required to increase breastfeeding duration.

Gyrus bipolar electrovaporization vs transurethral resection of the prostate: a randomized prospective single-blind trial with 1 y follow-up

The Gyrus system uses bipolar electrocautery with saline irrigation to vaporize prostatic tissue and is compared to transurethral resection of the prostate (TURP) in a randomized prospective study with 1 y follow-up. Outcomes measured were fluid absorption, blood loss, period of catheterization, hospital stay, symptom scores, quality of life, flow rates, and post-void residual volumes at 3, 6, and 12 months. All measured parameters were similar, although re-catheterization rates were higher (30% vs 5%) in the Gyrus group. Clot evacuation rates were higher in the TURP group (19% vs 0%). The Gyrus device is safe and produces results that are similar to TURP at 1 y.

Professional recommendations: disclosing facts and values

It is not unusual for patients and their families, when confronted with difficult medical choices, to ask their physicians for advice. This paper outlines the shades of meaning of two questions frequently put to physicians: "What should I do?" and "What would you do?" It is argued that these are not questions about objective matters of fact. Hence, any response to such questions requires an understanding, appreciation, and disclosure of the personal context and values that inform the recommendation. A framework for considering and articulating a response to these questions is suggested, using as a heuristic the phrasing "If I were you.../If it were me...".

A Practice-Research Model for Collaborative Partnership

The ability to integrate education, practice and research initiatives is well documented and the nursing literature presents several collaborative models that have emerged between educational institutions and service agencies to achieve this aim. However, a collaborative partnership agreement does more than integrate these initiatives; it is a vehicle by which the theory-clinical practice gap is bridged and best practice outcomes are achieved. This paper outlines an innovative collaborative partnership agreement between Fremantle Hospital and Health Service and Curtin University of Technology in Perth, Western Australia. The partnership engages academics in the clinical setting in two formalised collaborative appointments. This partnership not only enhances communication between educational and health services, but fosters the development of nursing research and knowledge. The process of the collaborative partnership agreement involved the development of a Practice-Research Model (PRM) of collaboration. This model encourages a close working relationship between registered nurses and academics, and has also facilitated strong links at the health service with the Nursing Research and Evaluation Unit, medical staff and other allied health professionals. Links have also been established with other health services and agencies in the metropolitan area. The key concepts exemplified in the application of the model include practice-driven research development, collegial partnership, collaborative ownership and best practice. Many specific outcomes have been achieved through implementation of the model, but overall the partnership between registered nurses and academics in the pursuit of research to support clinical practice has been the highlight. This has resulted in changes and innovations in current nursing practice and, importantly, dissemination of best practice outcomes.

Are universities preparing nurses to meet the challenges posed by the Australian mental health care system?

The preparedness of comprehensive nurses to work with the mentally ill is of concern to many mental health professionals. Discussion as to whether current undergraduate nursing programs in Australia prepare a graduate to work as a beginning practitioner in the mental health area has been the centre of debate for most of the 1990s. This, along with the apparent lack of interest and motivation of these nurses to work in the mental health area following graduation, remains a major problem for mental health care providers. With one in five Australians now experiencing the burden of a major mental illness, the preparation of a nurse who is competent to work with the mentally ill would appear to be a priority. The purpose of the present study was to determine third year undergraduate nursing students' perceived level of preparedness to work with mentally ill clients. The results suggested significant differences in students' perceived level of confidence, knowledge and skills prior to and following theoretical and clinical exposure to the mental health area. Pre-testing of students before entering their third year indicated that the philosophy of comprehensive nursing: integration, although aspired to in principle, does not appear to occur in reality.

Direct visualization of HIV-1-specific cytotoxic T lymphocytes during primary infection

OBJECTIVE

HIV-specific cytotoxic T lymphocytes (CTL) are believed to play an important role in containing viral replication throughout HIV-1 infection. Previous studies have attempted to quantify the HIV-1-specific CTL precursor frequency during primary HIV infection by using limiting dilution analysis, which almost certainly underestimates the true CTL frequency. Here we use a relatively new technique to quantify HIV-specific CD8 T cells in primary HIV infection.

METHODS

We have used soluble tetrameric complexes of HLA class I molecules complexed with HIV epitope peptides to study the dynamics and frequency of HIV-specific CD8 T cells in relation to plasma viral load in early HIV infection, in three patients with a highly focused HIV-specific CTL response.

RESULTS

We show that the frequencies of HIV-1-specific CD8 T cells in acute infection are significantly higher than previously documented and can be demonstrated well before full seroconversion. These studies also confirm the immunodominance of the B27-restricted response in HIV infection and demonstrate a close temporal relationship between the numbers of circulating HIV-specific CD8 T cells and viral load.

CONCLUSIONS

These findings strongly suggest that HIV-1-specific CD8 T cells are responding directly to the level of viral replication in early HIV infection and are a major factor in its control. In addition, the data indicate that immunodominance for CD8 T-cell responses is established in the acute phase of HIV infection.

High frequency of cytomegalovirus-specific cytotoxic T-effector cells in HLA-A*0201-positive subjects during multiple viral coinfections

How the cellular immune response copes with diverse antigenic competition is poorly understood. Responses of virus-specific cytotoxic T lymphocytes (CTL) were examined longitudinally in an individual coinfected with human immunodeficiency virus type 1 (HIV-1), Epstein-Barr virus (EBV), and cytomegalovirus (CMV). CTL responses to all 3 viruses were quantified by limiting dilution analysis and staining with HLA-A*0201 tetrameric complexes folded with HIV-1, EBV, and CMV peptides. A predominance of CMV-pp65-specific CTL was found, with a much lower frequency of CTL to HIV-1 Gag and Pol and to EBV-BMLF1 and LMP2. The high frequency of CMV-specific CTL, compared with HIV-1- and EBV-specific CTL, was confirmed in an additional 16 HLA-A*0201-positive virus-coinfected subjects. Therefore, the human immune system can mount CTL responses to multiple viral antigens simultaneously, albeit with different strengths.

Multilayer volume holographic optical memory

We demonstrate a scheme for volume holographic storage based on the features of shift selectivity of a speckle reference-wave hologram. The proposed recording method permits more-efficient use of the recording medium and yields greater storage density than spherical or plane-wave reference beams. Experimental results of multiple hologram storage and replay in a photorefractive crystal of iron-doped lithium niobate are presented. The mechanisms of lateral and longitudinal shift selectivity are described theoretically and shown to agree with experimental measurements.

Aetiology of childhood proptosis

OBJECTIVE

To retrospectively analyse causes of childhood proptosis and their investigations and treatment.

METHODOLOGY

The records of children under 15 years of age presenting with proptosis to The Children's Hospital, Camperdown, Sydney, were reviewed for the period 1983-93 inclusive.

RESULTS

Fifty-seven cases of proptosis were found. In order of frequency the causes were; orbital cellulitis 22, thyroid eye disease 8, optic nerve +/- optic chiasm glioma 8, orbital rhabdomyosarcoma 7, metastatic neuroblastoma 4, orbital neurofibroma 3, orbital haemangioma 2, metastatic Ewing's sarcoma 2 and orbital dermoid cyst 1. Treatment depended on the cause (antibiotics, antithyroid drugs, chemotherapy, radiotherapy, surgery) and was multidisciplinary.

CONCLUSIONS

The most common cause of proptosis in children presenting to The Children's Hospital, Camperdown, Sydney, was infective orbital cellulitis. The most useful initial investigation was an orbital computed tomography scan. Treatment depended on the cause of the proptosis and was multidisciplinary.

Assessment of self-report in HIV surveillance: a pilot study

The basis of HIV exposure category classification was investigated among selected cases of newly diagnosed HIV infection. Questionnaires seeking specific information on patient-reported exposure to HIV were forwarded to doctors who had requested the HIV antibody test for patients who met the study sample criteria. The cases of interest were those newly diagnosed between 1 January and 31 October 1991 and notified to state and territory health authorities as having been attributed to exposures to HIV other than male homosexual contact or receipt of blood, blood products or tissue. A total of 158 questionnaires was forwarded and 59 per cent were returned. Among the returned questionnaires included in the study sample, exposure to HIV on the original notification to the health authority was given as injecting drug use (8 per cent, 3 of 37), heterosexual contact (46 per cent, 17 of 37), or unavailable (46 per cent, 17 of 37). A clear basis for HIV exposure category classification was provided on the questionnaires for 70 per cent (7 of 10) of cases among women, whereas among men whose infection was attributed to heterosexual contact, a basis for exposure category classification was specified for only 43 per cent (10 of 23) of cases. Although the study was limited by the low response rate, use of the questionnaire provided a relatively simple means for assessing self-reported HIV exposure history.

Wound management in patients with epidermolysis bullosa

An examination of the treatment options available — including dressings and antimicrobial therapy — for patients with this condition

Prophylaxis against postsplenectomy pneumococcal infection

An excess risk of overwhelming sepsis following splenectomy is well established. In view of this, surgical responsibility must embrace the administration of pneumococcal prophylaxis. Current recommendations vary, but routine pneumococcal vaccination, together with penicillin prophylaxis in selected patients, is advocated widely. This retrospective review of 75 patients undergoing splenectomy was undertaken in order to evaluate the extent to which current practice complies with these recommendations. Among surviving patients, the incidence of vaccination with polyvalent pneumococcal vaccine (PPV) was found to vary according to operative indication. All haematological patients received pre-operative PPV. Two-thirds of multitrauma patients were vaccinated, while 42% of patients who required splenectomy following accidental intra-operative trauma received PPV. Only 11% of patients who underwent incidental splenectomy were vaccinated. Long-term antibiotic prophylaxis was commenced in 33% of surviving patients under 20 years of age, and in 8% with underlying malignancy. These results highlight a need for greater vigilance in the administration of pneumococcal prophylaxis, particularly following accidental or incidental splenectomy.