Results of a Search for Sub-GeV Dark Matter Using 2013 LUX Data.

The scattering of dark matter (DM) particles with sub-GeV masses off nuclei is difficult to detect using liquid xenon-based DM search instruments because the energy transfer during nuclear recoils is smaller than the typical detector threshold. However, the tree-level DM-nucleus scattering diagram can be accompanied by simultaneous emission of a bremsstrahlung photon or a so-called "Migdal" electron. These provide an electron recoil component to the experimental signature at higher energies than the corresponding nuclear recoil. The presence of this signature allows liquid xenon detectors to use both the scintillation and the ionization signals in the analysis where the nuclear recoil signal would not be otherwise visible. We report constraints on spin-independent DM-nucleon scattering for DM particles with masses of 0.4-5 GeV/c^{2} using 1.4×10^{4} kg day of search exposure from the 2013 data from the Large Underground Xenon (LUX) experiment for four different classes of mediators. This analysis extends the reach of liquid xenon-based DM search instruments to lower DM masses than has been achieved previously.

First Searches for Axions and Axionlike Particles with the LUX Experiment.

The first searches for axions and axionlike particles with the Large Underground Xenon experiment are presented. Under the assumption of an axioelectric interaction in xenon, the coupling constant between axions and electrons g_{Ae} is tested using data collected in 2013 with an exposure totaling 95 live days ×118 kg. A double-sided, profile likelihood ratio statistic test excludes g_{Ae} larger than 3.5×10^{-12} (90% C.L.) for solar axions. Assuming the Dine-Fischler-Srednicki-Zhitnitsky theoretical description, the upper limit in coupling corresponds to an upper limit on axion mass of 0.12 eV/c^{2}, while for the Kim-Shifman-Vainshtein-Zhakharov description masses above 36.6 eV/c^{2} are excluded. For galactic axionlike particles, values of g_{Ae} larger than 4.2×10^{-13} are excluded for particle masses in the range 1-16 keV/c^{2}. These are the most stringent constraints to date for these interactions.

Limits on Spin-Dependent WIMP-Nucleon Cross Section Obtained from the Complete LUX Exposure.

We present experimental constraints on the spin-dependent WIMP-nucleon elastic cross sections from the total 129.5 kg yr exposure acquired by the Large Underground Xenon experiment (LUX), operating at the Sanford Underground Research Facility in Lead, South Dakota (USA). A profile likelihood ratio analysis allows 90% C.L. upper limits to be set on the WIMP-neutron (WIMP-proton) cross section of σ_{n}=1.6×10^{-41} cm^{2} (σ_{p}=5×10^{-40} cm^{2}) at 35 GeV c^{-2}, almost a sixfold improvement over the previous LUX spin-dependent results. The spin-dependent WIMP-neutron limit is the most sensitive constraint to date.

Results from a Search for Dark Matter in the Complete LUX Exposure.

We report constraints on spin-independent weakly interacting massive particle (WIMP)-nucleon scattering using a 3.35×10^{4} kg day exposure of the Large Underground Xenon (LUX) experiment. A dual-phase xenon time projection chamber with 250 kg of active mass is operated at the Sanford Underground Research Facility under Lead, South Dakota (USA). With roughly fourfold improvement in sensitivity for high WIMP masses relative to our previous results, this search yields no evidence of WIMP nuclear recoils. At a WIMP mass of 50 GeV c^{-2}, WIMP-nucleon spin-independent cross sections above 2.2×10^{-46} cm^{2} are excluded at the 90% confidence level. When combined with the previously reported LUX exposure, this exclusion strengthens to 1.1×10^{-46} cm^{2} at 50 GeV c^{-2}.

First results from the LUX dark matter experiment at the Sanford underground research facility.

The Large Underground Xenon (LUX) experiment is a dual-phase xenon time-projection chamber operating at the Sanford Underground Research Facility (Lead, South Dakota). The LUX cryostat was filled for the first time in the underground laboratory in February 2013. We report results of the first WIMP search data set, taken during the period from April to August 2013, presenting the analysis of 85.3 live days of data with a fiducial volume of 118 kg. A profile-likelihood analysis technique shows our data to be consistent with the background-only hypothesis, allowing 90% confidence limits to be set on spin-independent WIMP-nucleon elastic scattering with a minimum upper limit on the cross section of 7.6 × 10(-46) cm(2) at a WIMP mass of 33 GeV/c(2). We find that the LUX data are in disagreement with low-mass WIMP signal interpretations of the results from several recent direct detection experiments.

Use of 3D imaging and awareness of GEC-ESTRO recommendations for cervix cancer brachytherapy throughout Australia and New Zealand.

INTRODUCTION: A 2005 survey of practices indicated limited use of three-dimensional (3D) imaging modalities and planning methods in cervix cancer brachytherapy in Australia and New Zealand. However, advancing technologies and published recommendations are influencing change. This survey aims to identify both changes in practice and awareness and uptake of Groupe European de Curietherapie of the European Society for Therapeutic Radiology and Oncology (GEC-ESTRO) recommendations. METHODS: A survey was emailed to all radiotherapy departments with brachytherapy facilities. Twenty departments practise brachytherapy for cancer of the cervix. The survey consisted of five questions enquiring about use and type of 3D imaging; rate of reimaging and replanning; and contouring, prescribing and reporting practices. RESULTS: A 100% response rate was obtained. Sixty-five per cent of departments use 3D CT imaging to plan brachytherapy insertions. Thirty per cent of departments use two-dimensional (2D) x-rays. Four departments (20%) use a combination of imaging modalities including CT, ultrasound and MRI. Sixty-five per cent of departments reimage and replan for each insertion. Four departments (20%) contour, prescribe dose and report treatment according to GEC-ESTRO recommendations. CONCLUSIONS: There has been a marked increase in the use of 3D imaging and awareness of GEC-ESTRO recommendations. Implementation and reporting of image-based gynaecological brachytherapy is strongly dependent on local resources and infrastructure.

Brachytherapy for cancer of the cervix: an Australian and New Zealand survey of current treatment techniques.

Establishing guidelines for the practice of brachytherapy throughout Australia and New Zealand is one of the goals of the Australasian Brachytherapy Group. To better appreciate Australasian resources and conditions, the group conducted a survey in early 2005. The aims were to survey current practices, to emphasize variations in practice and to determine the availability of advanced imaging and treatment methods to assess resources. A survey was sent to all Australian and New Zealand radiotherapy departments. The survey requested details of treatment with respect to external beam radiotherapy, brachytherapy, optimization methods, reporting methods, scheduling brachytherapy and access to imaging and methods of work-up. Thirty-four departments were contacted with 27 (79%) responses returned. Twenty-one departments use brachytherapy. Doses and fractionation schedules varied and use of sectional imaging was minimal. Individualized dosimetry is practised in a limited fashion by 60% of the surveyed departments. There is high compliance with International Commission on Radiation Units 38 dose reporting recommendations. All brachytherapy units identified have access to CT and 85% to MRI within the hospital settings. Brachytherapy for cancer of the cervix is, currently, largely based on the Manchester system. The survey did emphasize considerable variation in dose and fractionation schemes between departments. The Australasian Brachytherapy Group subgroup intends to proceed with the process of formulating recommendations for cervix brachytherapy. It is intended that these will cover the use of image-based planning and treatment, target definition(s), verification of brachytherapy treatments and a uniform dose-reporting mechanism.

Leadership: a skill, not a role.

The ever-changing healthcare landscape demands leaders who can help navigate through the turbulence. At a time when the demand for leaders in healthcare continues to grow, many wonder whether there is a pending leadership shortage. This perception is fostered by the confusion about how leaders are defined. For many the definition of a leader is synonymous with a job title or role, such as a Manager or Director. Leadership, however, is not a job description; rather, it is influencing others to contribute to a positive outcome. All clinicians, particularly advanced practice nurses, must take the responsibility of finding solutions to the current challenges in healthcare and work through others to achieve a better outcome. In this article leadership is defined by skill sets, not job title, and offers specific strategies to enhance advanced practice nurses' leadership skills.

Mantle irradiation alone for clinical stage I-II Hodgkin's disease: long-term follow-up and analysis of prognostic factors in 261 patients.

PURPOSE: To evaluate mantle radiotherapy (MRT) alone as the initial therapy of patients with clinical stage (CS) I-II Hodgkin's disease (HD). PATIENTS AND METHODS: We performed a retrospective study of patients treated with MRT alone for CS I-II supradiaphragmatic HD between 1969 and 1994. Prognostic factor analysis was performed for progression-free survival (PFS) and overall survival (OS). Outcome was also assessed in favorable cohorts defined in the literature. RESULTS: There were 261 eligible patients. The median follow-up period for surviving patients was 8.4 years (range, 1.8 to 27.4 years). The 10-year OS rate was 73%. Multifactor analysis for OS showed that age was the only important prognostic factor. The 10-year PFS rate was 58%. On multifactor analysis for PFS, the most important prognostic factors were clinical stage, B symptoms, histology, number of sites, and tumor bulk. The 10-year PFS rate for lymphocyte-predominant disease was 81% for stage I and 78% for stage II. In favorable patient cohorts defined in the literature, the 10-year PFS rate ranged from 70% to 73% for the whole group and from 71% to 90% in patients with favorable stage I disease, but only from 48% to 57% in patients with favorable stage II disease. On competing-risks analysis, the cumulative 10-year incidence of first site of failure in the para-aortic/splenic region alone was 10.5%. Sixty percent of relapsed patients remain progression-free at 10 years after chemotherapy salvage. CONCLUSION: These results support the use of MRT alone in patients with favorable CS I HD and CS I-II HD with lymphocyte-predominant histology. The remainder of patients with CS I-II HD require more intensive treatment.

Postoperative adjuvant radiotherapy and 5-fluorouracil chemotherapy for rectal carcinoma.

Postoperative combined modality therapy with radiotherapy and 5-fluorouracil (5FU) chemotherapy is an effective adjuvant approach that reduces locoregional and distant metastatic disease in patients with high-risk rectal carcinoma. However, this approach results in a treatment regimen of at least 6 months' duration. The present prospective study investigates the integration of radiotherapy and 5FU chemotherapy in a protocol designed to minimize toxicity and reduce the overall treatment time. A total of 40 patients with TNM stage II or III disease received postoperative radiotherapy at four fractions per week with weekly 5FU bolus injections delivered on the fifth non-radiotherapy day. Patients also received systemic chemotherapy with leucovorin both before and after pelvic irradiation, with the total treatment duration extending for only 18 weeks. Patients were able to complete radiotherapy in 90% of cases, while the delivery of full-dose chemotherapy was achievable in the vast majority. The incidence of haematologic and gastrointestinal toxicities requiring the cessation of treatment was acceptable. With a median follow-up of 20.9 months among surviving patients, the estimated progression-free and overall survival at 2 years were 71% and 79%, respectively.

The development of a provincial radiation oncology service: the first year report and its implications for future developments.

This study compares the actual first year's workload of a new radiation oncology department with that predicted, and assesses the impact of the differences, and their implications for future similar developments. The treatment records and diaries for the Geelong Hospital Radiation Oncology Department were reviewed after the first 12 months of operation (opened in June 1992). Statistics relating to the number of patients seen, number treated, diagnosis, etc., were evaluated and compared to the original estimates based upon population statistics and likely referral rates. Nine hundred and seven new patients were seen in this period, and from them 718 courses of treatment were initiated. One hundred and eighty-nine cases (20% of referrals) were seen but not treated. A further 102 treatment courses (14% of total) were initiated upon patients who had previously been irradiated. Forty-six per cent of patients were managed by 10 fractions or fewer, and a further 23% by 25 or more fractions. Eighty per cent of patients were managed by one or two fields. Electrons were used in only 14% of cases. Further calculations suggested a further possible 441 cases of referral could be expected, based upon current population statistics. Referral rates for radiation oncology are highly dependent on a number of factors. As a result, estimates of referrals and hence the size of a department required for a given population vary widely. Our data support these concepts, and the concept that referral is also strongly dependent upon the distance patients need to travel. In considering the development of units outside of major cities it is suggested that referrals are likely to be on the high side of estimates and a minimum two-machine unit is essential to cover the given workload.

Future expectations for critical care nurses. Competence in immunotherapy.

Immunotherapy is a promising therapy for the treatment of some forms of cancer. This research therapy uses normal immune system substances such as IL-2 to stimulate the immune system to kill tumor cells while sparing normal tissues. Many side effects of IL-2 have been identified. The most serious of these effects involves the cardiovascular, renal, and pulmonary systems. Patients who experience these IL-2-related toxicities are effectively managed in the intensive care unit. The critical care nurse has a major role in the monitoring and management of this patient population. Hospitals that participate in this research treatment for cancer are increasing. In the near future, competence in immunotherapy will be an expectation for many critical care nurses.

The form and presentation of tuberculosis over a 10-year interval in Leeds.

Over the 10-year period 1973-82 1958 cases of tuberculosis were notified in Leeds (population 728 000). Records were traced for 1673 patients and analysed for age, race, sex, sputum status, site of tuberculosis, route of diagnosis and occupation. These results are presented. The tuberculosis screening service at the Leeds Chest Clinic diagnosed 172 cases of tuberculosis from 13 794 contacts screened and 41 cases from 12 572 newly arrived immigrants representing 10.3% and 2.4% respectively of the cases for whom records could be traced. Of these cases discovered by the tuberculosis screening service 25 were sputum positive. A further 15 cases were diagnosed from 2638 contacts screened by the static Mass Miniature Unit. The cost of the screening service at the Leeds Chest Clinic is estimated to be a minimum of 2000 pounds for every case of tuberculosis diagnosed.