Search

This document is the product of a stellarator community workshop, organized by the National Stellarator Coordinating Committee and referred to as Stellcon, that was held in Cambridge, Massachusetts in February 2016, hosted by MIT. The workshop was widely advertised, and was attended by 40 scientists from 12 different institutions including national labs, universities and private industry, as well as a representative from the Department of Energy. The final section of this document describes areas of community wide consensus that were developed as a result of the discussions held at that workshop. Areas where further study would be helpful to generate a consensus path forward for the US stellarator program are also discussed. The program outlined in this document is directly responsive to many of the strategic priorities of FES as articulated in “Fusion Energy Sciences: A Ten-Year Perspective (2015–2025)” [1]. The natural disruption immunity of the stellarator directly addresses “Elimination of transient events that can be deleterious to toroidal fusion plasma confinement devices” an area of critical importance for the US fusion energy sciences enterprise over the next decade. Another critical area of research “Strengthening our partnerships with international research facilities,” is being significantly advanced on the W7-X stellarator in Germany and serves as a test-bed for development of successful international collaboration on ITER. This report also outlines how materials science as it relates to plasma and fusion sciences, another critical research area, can be carried out effectively in a stellarator. Additionally, significant advances along two of the Research Directions outlined in the report; “Burning Plasma Science: Foundations—Next-generation research capabilities”, and “Burning Plasma Science: Long pulse—Sustainment of Long-Pulse Plasma Equilibria” are proposed.

The Direct Fusion Drive (DFD), a compact, anuetronic fusion engine, will enable more challenging exploration missions in the solar system. The engine proposed here uses a deuterium–helium-3 reaction to produce fusion energy by employing a novel field-reversed configuration (FRC) for magnetic confinement. The FRC has a simple linear solenoid coil geometry yet generates higher plasma pressure, hence higher fusion power density, for a given magnetic field strength than other magnetic-confinement plasma devices. Waste heat generated from the plasma׳s Bremsstrahlung and synchrotron radiation is recycled to maintain the fusion temperature. The charged reaction products, augmented by additional propellant, are exhausted through a magnetic nozzle. A 1 MW DFD is presented in the context of a mission to deploy the James Webb Space Telescope (6200 kg) from GPS orbit to a Sun–Earth L2 halo orbit in 37 days using just 353 kg of propellant and about half a kilogram of 3He. The engine is designed to produce 40 N of thrust with an exhaust velocity of 56.5 km/s and has a specific power of 0.18 kW/kg.

Study Objective To estimate the safety and efficacy of the HydroThermAblator (HTA) system for performance of endometrial ablation in the medical office setting using local anesthesia and minimal oral sedation and to compare results obtained in patients with submucous myomas with those in patients with normal endometrial cavities. Design Retrospective cohort analysis of 246 HTA procedures (Canadian Task Force classification II-2). Setting Medical offices of a suburban community medical center that is part of a large health maintenance organization. Patients Two hundred forty-six women aged 28 to 63 years (mean [SD], 45.1 [6.0] years) with abnormal uterine bleeding unresponsive to conservative management, including 104 patients (42.3%) with submucous myomas. Type 0 or type I myomas were present in at least 86 patients with submucous myomas (82.7%) and ranged from 1 to 4 cm in greatest diameter. In the other 18 patients, submucous myomas were not classified by type. Patients were evaluated at 2 to 70 months after the procedure (median follow-up, 31.0 months). Three patients were lost to follow-up, and 12 patients underwent hysterectomy for indications other than abnormal bleeding and were excluded from the analysis. Thus, 231 patients were included in the analysis. Interventions Endometrial ablation was performed using the HTA system with paracervical or intracervical block after oral premedication with ibuprophen, diazepam, and acetominophen or hydrocodone and intramuscular ketorolac. No intravenous or intramuscular narcotics were used. The anesthesia regimen was the same in patients with submucous myomas as in those with normal cavities, and the procedure was performed in exactly the same manner. All procedures were performed in the medical office procedure room by 7 board-certified gynecologists; most procedures were performed by the authors. Measurements and Main Results Of the 231 patients included in the analysis, 121 (53.4%) reported postablation amenorrhea, 62 (26.8%) reported light menses or spotting, 21 (9.1%) reported normal menses, 15 (6.5%) reported menorrhagia, and 12 (5.2%) underwent hysterectomy because of bleeding. In the 136 patients with normal cavities, amenorrhea was achieved in 84 patients (61.8%), oligomenorrhea in 35 (25.7%), and eumenorrhea in 12 (8.8%). Four patients (2.9%) continued to have menorrhagia requiring medical treatment. In the 95 patients with submucous myomas, amenorrhea was reported by 37 patients (38.9%), oligomenorrhea by 27 (28.4%), eumenorrhea by 9 (9.5%), and menorrhagia by 11 (11.6%). In 11 patients (11.6%), hysterectomy was performed because of menorrhagia. All patients who underwent hysterectomy had multiple myomas, and 9 (81.8%) also had adenomyosis. The failure rate, defined as patients with menorrhagia or undergoing hysterectomy because of bleeding, was 11.7% overall. The failure rate in patients with submucous myomas and normal cavities was 23.2% and 3.7%, respectively (relative risk, 6.3; 95% confidence interval, 2.5–16.0). While the failure rate in the group with myomas was statistically significantly higher than in the group without myomas, the failure rate in the myoma group was still comparable to that achieved using electrosurgical resection and ablation of similar types of myomas as reported in the literature. The amenorrhea rate achieved in the myoma group (38.9%) was also comparable to that achieved in US Food and Drug Administration pivotal trials in patients with normal cavities treated using all of the nonhysteroscopic global ablation devices as well those treated using rollerball endometrial ablation. The rate of hysterectomy because of bleeding was 5.2% overall. The hysterectomy rate in patients with submucous myomas and normal cavities was 11.6% and 0.7%, respectively. Only 1 procedure was discontinued (at 8 minutes) because of pain. Four patients had postoperative endometritis, with 2 requiring hospitalization for intravenous antibiotic therapy. Two false passages were created while dilating the cervix, with subsequent inability to perform the procedure. Conclusions Hydrothermablation performed in the medical office using local anesthesia seems to be a safe, effective, and cost-saving procedure for treatment of abnormal uterine bleeding in women with both normal and myomatous uteri. Although the success rate in patients with normal cavities was higher than that achieved in patients with submucous myomas, hysterectomy because of abnormal bleeding related to myomas was avoided in 88.4% of the group with myomas.

A public health perspective based on social justice and a population health point of view emphasizes pharmacy policy innovations regarding safety and costs. Such policies that effectively reduce costs include controlling profits, establishing profit targets, extending prescription providers, revising prescription classification schemes, emphasizing generic medications, and establishing formularies. Public education and universal programs may reduce costs, but co-pays and "cost-sharing" do not. Switching medications to over-the-counter (OTC) status, pill splitting, and importing medication from abroad are poor substitutes for authentic public health pharmacy policy. Where policy changes yield savings, public health insists that these savings should be used to increase access and improve population health. In the future, pharmacy policies may emphasize public health accountability more than individual liberty because of potential cost savings to society. Fear of litigation, as an informal mechanism of focusing manufacturer's attention on safety, is inefficient; public health pharmacy policy regarding safety looks toward a more active regulatory role on the part of government. A case study of direct-to-consumer advertising illustrates the complexity of public health pharmacy policy.

Sustainability in the context of China is an immediate and massive concept. A society of 1.3 billion has economic growth of 9-10% and a dramatic rise in life expectancy. It has rapidly-accumulating material wealth, major lifestyle changes and growing inequalities. It is putting great pressure on natural resources such as water and air quality. The Chinese Government's new 5-year plan uses the term 'sustainable development' as an important social goal for the first time. Sustainability requires a global effort and Sino-European partnerships are important.

The Medicine and Public Health Initiative (MPHI) was created jointly 10 years ago by the American Medical Association and the American Public Health Association to bridge the nearly century-wide gulf between the respective disciplines. We review the history of MPHI and its growing significance in light of recent terrorism events. We report on current MPHI activities by examining three bellwether states-California, Florida, and Texas-as well as international sites. Upon its inception, MPHI was rapidly embraced and nationally disseminated. Sustainability 10 years later in the post-911 world requires renewed commitment by all collaborators. In order to meet the numerous health challenges facing our nation, from terrorism to chronic disease, and for MPHI to be successful, medicine and public health must work in tandem.

Study objective To assess the efficacy of performing myomectomies through 3- to 6-cm incisions for the removal of myomas up to 14 cm in diameter. Design A retrospective analysis of 139 myomectomies performed at our center from January 1995 through December 2003 (Canadian Task Force classification II-3). Setting A suburban medical center, part of a large prepaid health maintenance organization. Patients One hundred thirty-nine women. Interventions Myomectomies were performed through 3- to 6-cm suprapubic cruciate incisions using atraumatic elastic retractors with or without laparoscopic assist. Myomas were morcellated with a scalpel before being enucleated. The uterus was repaired in a classic three-layered closure in all cases. All procedures were performed in the ambulatory surgery unit of our hospital, which is part of the main operating room. Measurements and main results The median age of the patients in this series was 30.0 years (range 23–56 years). The median weight of the myomas removed was 275.0 g (range of 30–975 g). One hundred thirty-seven (98.5%) of 139 patients were discharged in 23 hours or less, with 24 patients leaving within 4 hours and 61 within 8 hours. The median length of stay was 6.0 hours, with two patients remaining hospitalized for 48 hours. The median operating time was 110 minutes (range 44–260 min). Estimated blood loss ranged from 50 to 2000 mL, with a median of 300 mL. Three hysterectomies were performed: one as an emergency for hemorrhage and two for recurrent myomas. Three patients developed wound seromas, and one developed a wound infection. Conclusions Minilaparotomy myomectomy is a safe, effective minimally invasive alternative to laparoscopic myomectomy. Early discharge and return to normal activities is comparable to laparoscopy and is far more cost effective. It affords the ability to palpate the uterus and close the myometrial defect easily with a standard three-layered closure making it particularly suitable for gynecologists with limited laparoscopic suturing skills.

To estimate the ectopic pregnancy rate at Kaiser Permanente, Northern California, during 1997-2000.Computerized data systems covering inpatient, outpatient, and pharmacy records were reviewed for evidence of ectopic pregnancies during the study period. Denominator data were calculated from computerized utilization and membership data for the same period.We identified 2,617 ectopic pregnancies that occurred between 1997 and 2000 among 126,451 reported pregnancies for an annual rate of 20.70 per 1,000 reported pregnancies and 1.03 per 1,000 women 15-44 years old. There was no evidence of a trend over time in these data. The rate increased with increasing age. Approximately 35% of these women were medically treated, and we observed an increase over time in the proportion of women who were medically treated.Using computerized data systems in a large integrated health delivery system, we found that the rate of ectopic pregnancy in 1997-2000 was similar to the national rate in 1990-1992, when national data were last available. These data suggest that the ectopic pregnancy rate is not increasing, although differences in the study populations need to be kept in mind. Medical treatment seems to be increasing over time.

An overview of the research capabilities and the future plans on the MA-class National Spherical Torus Experiment (NSTX) at Princeton is presented. NSTX research is exploring the scientific benefits of modifying the field line structure from that in more conventional aspect ratio devices, such as the tokamak. The relevant scientific issues pursued on NSTX include energy confinement, MHD stability at high beta, non-inductive sustainment, solenoid-free start-up, and power and particle handling. In support of the NSTX research goal, research tools are being developed by the NSTX team. In the context of the fusion energy development path being formulated in the US, an ST-based Component Test Facility (CTF) and, ultimately a high beta Demo device based on the ST, are being considered. For these, it is essential to develop high performance (high beta and high confinement), steady-state (non-inductively driven) ST operational scenarios and an efficient solenoid-free start-up concept. We will also briefly describe the Next-Step-ST (NSST) device being designed to address these issues in fusion-relevant plasma conditions.

Study Objective To assess the safety and efficacy of the HydroThermAblator (HTA) system to treat patients with menorrhagia and submucous myomas up to 4 cm in diameter. Design Retrospective, multicenter, cohort study (Canadian Task Force classification II-2). Setting Two medical centers from a large, prepaid, multispecialty health maintenance organization. Patients Twenty-two women. Intervention HTA endometrial ablation. Measurements and Main Results The HTA circulates free-flowing, heated (90° C) saline in the uterine cavity for 10 minutes under direct hysteroscopic control. All procedures were performed in the office under local anesthesia after premedication with oral anxiolytic and analgesic agents. At least 1 year after treatment (average follow-up 15.4 mo, range 12–20 mo), women were contacted regarding their menstrual history. Success was defined as no additional medical or surgical intervention. Amenorrhea was defined as no bleeding, eumenorrhea as normal periods, and oligomenorrhea as less than a normal period. Twelve patients (54%) reported complete amenorrhea; 7 were premenopausal (41% amenorrhea rate) and 5 were postmenopausal (100% amenorrhea rate). Five (23%) reported oligomenorrhea and three (14%) eumenorrhea, and were very satisfied with the result. The overall success rate was 91%. Of two failures (9%), one woman had a repeat HTA 13 months later for menorrhagia. The other had a repeat HTA for persistent spotting and sustained a false passage and small perforation before the procedure began. She elected to have a vaginal hysterectomy 1 month later. Although the results are not statistically significant, patients were extremely satisfied with the outcomes, and no serious complications were related to the device or its use for this indication. Conclusion HTA is probably safe and effective in treating women with menorrhagia and submucous myomas up to 4 cm in diameter. It offers advantages over hysterectomy and electrosurgical resection since it is an office-based procedure, and significant advantages over other global ablation technologies that, by their design, are unable to treat significantly distorted uterine cavities.

PURPOSE. Cataract surgery is one of the most successful procedures in medicine, and outcome is typically measured by a single factor – improvement in visual acuity. Health-related functional outcome testing, which quantifies the patient's self-reported perception of impairment, can be integrated with objective clinical findings. Based on the patient's self-assessed lifestyle impairment, the physician and patient together can make an informed decision on the treatment that is most likely to benefit the patient. METHOD. A functional outcome test (the Houston Vision Assessment Test – HVAT, copyrighted 1990, 1992) was evaluated in a cataract population of 149 patients from seven study centers. Test results were correlated with objective ophthalmic endpoints. The HVAT divides an estimated total impairment into subcomponents of Visual Impairment (correctable by cataract surgery) and non-visual Physical Impairments (co-morbidities not affected by cataract surgery). RESULTS. In this prospective study, the average...

Purpose Cataract surgery is one of the most successful procedures in medicine, and outcome is typically measured by a single factor - improvement in visual acuity. Health-related functional outcome testing, which quantifies the patient's self-reported perception of impairment, can be integrated with objective clinical findings. Based on the patient's self-assessed lifestyle impairment, the physician and patient together can make an informed decision on the treatment that is most likely to benefit the patient. Method A functional outcome test (the Houston Vision Assessment Test - HVAT, copyrighted 1990, 1992) was evaluated in a cataract population of 149 patients from seven study centers. Test results were correlated with objective ophthalmic endpoints. The HVAT divides an estimated total impairment into subcomponents of Visual Impairment (correctable by cataract surgery) and non-visual Physical Impairments (co-morbidities not affected by cataract surgery). Results In this prospective study, the average Visual Impairment score improved by 19 points (65%) following cataract extraction (the mean HVAT Visual Impairment score was 29 points before surgery and 10 points at 5 months post-surgery, a change of 65%). Physical Impairment remained unchanged by surgery. Visual acuity was a poor predictor of Visual Impairment. Conclusions The HVAT has 11 simple questions. It may be self-administered and is available on the Internet: http://www.DHAC.com. The physician may err if his decision in favor of cataract surgery is based only on visual acuity. The HVAT has the potential to guide the decision-making process between patient and physician.

Electrosurgical vaporization, first performed by urologists in prostate surgery, is useful during operative hysteroscopy for endometrial ablation and myomectomy. From June 1995 through May 1996, 9 surgeons performed 44 endometrial ablations and hysteroscopic myomectomies using the vaporization electrode. Our experience with this technique thus far has been very favorable. The procedure is less expensive than laser ablation and is easier to teach than wire loop resection. It is also less tedious than wire loop resection since myoma chips that often obstruct the operator's view are eliminated. Long-term efficacy of this technique remains to be proved.

This article discusses two approaches to controlling the newly identified influenza A (H1N1): via Bayesian and frequentist statistical reasoning. This study reviewed the measures implemented in China as an example to illustrate these two approaches. Since May 2009, China has deployed strict controlling mechanisms based on the strong prior Bayesian assumption that the origin of influenza A (H1N1) was from outside China and as such strict border control would keep the virus from entering China. After more than 4 months of hard work by Chinese health professionals and officials, the number of confirmed influenza A (H1N1) has increased steadily against the expectations of the general public. Taking into account the great financial burden in maintaining strict measures, Chinese health authorities have slowly adjusted their policies of controlling influenza A (H1N1) in China according to frequentist reasoning since July 2009.

Hysteroscopy and endometrial ablation using the second-generation devices are safe, generally well tolerated, and effective when performed in the medical office as opposed to the ambulatory surgery center or hospital operating room. Not only does this benefit the patient and physician in terms of convenience and cost savings, and the overall economic benefit to the health care system is great. The availability of modern hysteroscopic and video equipment, the advent of second-generation "global"endometrial ablation devices, and use of minimal sedation combined with effective local anesthesia have made office procedures possible. Several states have enacted specific regulations and requirements for office based surgery. It is incumbent on the physician to be aware of which local regulations are applicable and the level of procedure he or she is willing to perform before embarking on an office-based surgery program. The AAGL ListServ discussion forum provides members with an invaluable source of clinical opinion about patient care issues in minimally invasive gynecology. These opinions come from experts around the world representing both academic centers and clinical practice who respond to questions or issues posed by colleagues. This review discusses each of the second-generation endometrial ablation devices in detail and some of the more pertinent issues related to office hysteroscopy and global endometrial ablation that were posted on the ListServ. Rollerball and transcervical resection of the endometrium are not discussed because the overwhelming majority of these procedures are performed in the operating room and there is little potential for their becoming office procedures. Practical clinical tips based on the evidence in the literature are discussed.

This article demonstrates a proof-of-concept system capable of producing Fourier-transform limited ns-pulses tunable over a wide spectral range. By combining the large tuning range of the Ti:saphire crystal and combinations of nonlinear frequency conversion processes including sum-and difference frequency mixing with the pump radiation, a spectral coverage of 180 nm to 5000 mum is possible when considering up to three nonlinear processes.

In the 1960s or 1970s, gynecology residency training emphasized vaginal hysterectomy as the preferred technique for treating many conditions now managed by less invasive alternatives. This led gynecologists to become very skilled at operating through very small incisions. More recently, as these less invasive procedures are rapidly becoming the standard of care, and women are having fewer babies, vaginal surgery is performed less often. Because our young colleagues are acquiring less experience with this technique, the skill of operating through a very small incision is becoming a lost art. Of the 600,000 hysterectomies done in the United States each year—a number which has remained stable for the past 20 years—65% to 75% are done through large abdominal incisions.1 Rates in the Kaiser Permanente Northern California (KPNC) Region are somewhat better: The rate of abdominal hysterectomy is 68%, the rate of vaginal hysterectomy is 21%, and 11% of these procedures are done laparoscopically. Although laparoscopic hysterectomy offers a minimally invasive alternative when vaginal hysterectomy is contraindicated or considered too difficult by the surgeon, laparoscopic hysterectomy has many drawbacks. The procedure is very costly because of its requirements for equipment and time in the operating suite and because the procedure has a very steep learning curve. However, when length of hospital stay and postoperative utilization of medical services are taken into account, laparoscopic hysterectomy in the KPNC Region is less expensive than abdominal hysterectomy but substantially more expensive than vaginal hysterectomy. In addition, compared with patients who have the more invasive (ie, abdominal) procedure, our patients who undergo vaginal or laparoscopic hysterectomy have better postoperative quality of life.2 Minilaparotomy is technically less difficult to perform than laparoscopic myomectomy … Development of Minilaparotomy Techniques Use of minilaparotomy in surgery for benign gynecologic disease has been well established.3 Laparoscopically assisted myomectomy was first reported by Nezhat et al in 1994.4 In their review of 57 cases, these authors concluded that the use of the minilaparotomy incision is a safe alternative to myomectomy done by laparotomy. Minilaparotomy is technically less difficult to perform than laparoscopic myomectomy, allows better closure of the uterine defect, and may require less time to perform. Most women in the series reported by Nezhat et al4 returned to normal activity within three weeks. In 2002, we adopted the Pelosi minilaparotomy hysterectomy technique as an effective alternative to laparoscopic hysterectomy and standard open laparotomy hysterectomy. First presented at the Global Congress of Gynecologic Endoscopy in 2002 and described in OBG Management in April 2003,5 the procedure relies on traditional open techniques learned by all Ob/Gyn residents and relies also on use of an inexpensive, soft, sleeve-type self-retaining abdominal retractor. Minilaparotomy is a minimally invasive procedure ideal for gynecologists who are less skilled in vaginal or laparoscopic surgery and who are more comfortable with the (standard) abdominal approach. In addition to combining the surgical principles and techniques of vaginal and laparoscopic surgery, minilaparotomy requires the same postoperative care as less invasive procedures. Detailed description of the surgical technique would be more appropriate for an obstetrics/gynecology journal; here I describe some of the most important technical principles of minilaparotomy.

Research on the Spherical Torus (or Spherical Tokamak) is being pursued to explore the scientific benefits of modifying the field line structure from that in more moderate aspect-ratio devices, such as the conventional tokamak. The Spherical Tours (ST) experiments are being conducted in various U.S. research facilities including the MA-class National Spherical Torus Experiment (NSTX) at Princeton, and three medium-size ST research facilities: Pegasus at University of Wisconsin, HIT-II at University of Washington, and CDX-U at Princeton. In the context of the fusion energy development path being formulated in the U.S., an ST-based Component Test Facility (CTF) and, ultimately a Demo device, are being discussed. For these, it is essential to develop high-performance, steady-state operational scenarios. The relevant scientific issues are energy confinement, MHD stability at high beta (B), noninductive sustainment, ohmic-solenoid-free start-up, and power and particle handling. In the confinement area, the NSTX experiments have shown that the confinement can be up to 50% better than the ITER-98-pby2 H-mode scaling, consistent with the requirements for an ST-based CTF and Demo. In NSTX, CTF-relevant average toroidal beta values bT of up to 35% with the near unity central betaT have been obtained. NSTX will be exploring advanced regimes where bT up to 40% can be sustained through active stabilization of resistive wall modes. To date, the most successful technique for noninductive sustainment in NSTX is the high beta-poloidal regime, where discharges with a high noninductive fraction ({approx}60% bootstrap current + neutral-beam-injected current drive) were sustained over the resistive skin time. Research on radio-frequency-based heating and current drive utilizing HHFW (High Harmonic Fast Wave) and EBW (Electron Bernstein Wave) is also pursued on NSTX, Pegasus, and CDX-U. For noninductive start-up, the Coaxial Helicity Injection (CHI), developed in HIT/HIT-II, has been adopted on NSTX to test the method up to Ip {approx} 500 kA. In parallel, start-up using radio-frequency current drive and only external poloidal field coils are being developed on NSTX. The area of power and particle handling is expected to be challenging because of the higher power density expected in the ST relative to that in conventional aspect-ratio tokamaks. Due to its promise for power and particle handling, liquid lithium is being studied in CDX-U as a potential plasma-facing surface for a fusion reactor.

OBJECTIVE: We compared quality of life, utilization, and costs for women undergoing elective abdominal, laparoscopically assisted vaginal, or vaginal hysterectomy within a managed-care organization. STUDY DESIGN: A prospective study of 287 women who underwent an elective hysterectomy was performed. RESULTS: Patients undergoing a vaginal hysterectomy reported returning to normal activity levels sooner and had more favorable quality-of-life scores than did those undergoing laparoscopically assisted vaginal hysterectomy or abdominal hysterectomy. Laparoscopically assisted vaginal hysterectomy was often nearly as favorable as vaginal hysterectomy, particularly at 28 days after the operation, whereas the abdominal hysterectomy group consistently reported the poorest postoperative quality-of-life scores. No significant differences were noted in utilization or costs in the 60-day preoperative period, whereas hospitalization and postoperative costs were highest among the abdominal hysterectomy group and lowest for those undergoing a vaginal hysterectomy. CONCLUSIONS: Vaginal hysterectomy resulted in better quality-of-life outcomes and lower utilization and costs compared with laparoscopically assisted vaginal or abdominal hysterectomy. (Am J Obstet Gynecol 1998;178:91-100.)

The investigation of animal cells in microstructures fabricated by semiconductor technology is a new field of research and has found its first biotechnological and medical uses. This paper contains selected examples of three-dimensional structures to handle and characterise adherently growing cells, to determine their adhesion, surface migration and to cultivate them under strong electric field. Two new principles, (i) the use of electronic resonances to increase polarisation forces and (ii) the computer-based investigation of cell rotation/cell dielectrophoresis by photoelement signal analysis, are explained. Additionally, some results dealing with the trapping and concentration of submicron particles such as viruses in extremely miniaturised electric field cages are given. Perspectives for such semiconductor micro-devices are outlined.

This report is an account of research undertaken to describe the steady, axisymmetric flow of plasmas through rocket nozzles, with attention directed to the use of magnetic fields for guiding or propelling the plasmas. The primary emphasis is on simply connected nozzles containing strictly longitudinal (B sub r, O, B sub z) magnetic fields to guide the plasma, with secondary consideration given to annular nozzles containing strictly azimuthal (O, B sub theta, O) magnetic fields to propel the plasma. The possibility and desirability of using hot plasmas in a repetitive mode is discussed, and motivates our consideration of an extensive range of parameters. Although slightly ionized gases having low temperatures (a fracture of an eV) and low magnetic Reynolds numbers often are the objects of valid and useful research (for example, in connection with MHD generators, with MPD thrusters, and with arc heaters to provide sources of hot gas for expanding gas-dynamic flow fields) , the focus is upon the effective and efficient interaction of substantial plasmas with guiding or driving magnetic fields. Thus, focus is primarily on highly ionized plasmas that are not dominated by resistive dissipation. Some of the principal physics issues associated with these concepts are addressed, including the assumptions and limitations of the ideal MHD model, the magnitude and scaling of classical and anomalous transport losses and of radiation losses in hydrogen plasma during transit of plasma through the nozzle, and the transport-related detachment problem of how the plasma leaves the exit region of the nozzle.

This study investigates whether there is a built-up demand for health services that surfaces when people enroll through a group plan in a Health Maintenance Organization. The study population consists of newly enrolled subscriber units of the Kaiser Foundation Health Plan (Oregon Region). The utilization variables examined include the number of inpatient and outpatient contacts with the Plan, the number and type of specific services performed, and the type of outpatient contact. The enrollees were followed over 12 quarters (three years). The analysis showed that the first quarter stood out in three respects: its average number of inpatient and outpatient contacts were the lowest of any quarter; the mean numbers of radiology services and laboratory tests per outpatient contact were the highest during this quarter; and the highest proportion of regularly scheduled contacts and the lowest rate of patient cancellation of visits occurred during the first quarter. Hence, these data are not supportive of the idea of a built-up demand. Rather they suggest that the enrollee requires some time to learn how to deal with the system; and, once a new member contacts the system, the system may perform a number of tests to obtain baseline data about the enrolee. Additional analysis did not suggest the presence of any time trends in the utilization data.

The retention patterns of the Kaiser Foundation Health Plan (Oregon Region) were studied over a six-year period using a life table analysis. A 5% random sample, consisting of subscriber units that were enrolled at the initiation of the study of subsequently joined during the six-year period, were followed with respect to enrollment retention. The analysis presented here focuses on the 2,112 subscribers enrolled during the 1967-1970 period. These subscribers were characterized by the year they joined the plan and by their age and sex. The analyses showed that age of the subscriber and length of time on the plan consistently affected the probability of continued enrollment. The sex of the subscriber and the initial year of enrollment showed only a slight differential affect. A general pattern of high attrition in the first year, but rapid slackening thereafter, existed in all subgroup specific analyses. The utility of the analyses and the impact of the effect of differential membership retention on the plan are discussed.

be dismissed as simply a bit of hyperbole to attract the readers attention. While these comments are a reaction to research findings that contradict the beliefs of their author, they also reflect a very prevalent antiquantitative mindset that has contributed to a dangerous constriction of quantitative-based health services research and policy applications. This mindset is not doctrinaire. It exists among social critics and policymakers in liberal and conservative camps. Constrictions in both federal and state expenditures and shifts in funding priorities are moving to the detriment of health services research and inquiry into health care delivery. The nation's press has taken note of dramatic cutbacks in support for information systems and programs vital

The catastrophic health insurance bills introduced during the 96th U.S. Congress failed to consider the current role that Health Maintenance Organizations (HMO's) play in providing catastrophic protection and the potential negative impact such legislation may have on their competitive position. This article demonstrates that HMO's are providing this coverage by using the simulated health care expenditures for families in one HMO. The estimated proportion of families that incur catastrophic expenditures varies from 0.3 to 14.4%, depending on the definition used for catastrophic. The paper closes with a discussion of the potential adverse impact that the legislation would have had on HMO's.

This research applied the life table technique to nursing personnel data in two types of hospitals to illustrate how administrators can examine patterns of continued employment. Although a large proportion of nurses were short-stay employees, the teaching hospital was found to have a higher retention rate than the community hospital corporation. The retention patterns are examined by personal and professional characteristics, as well as by reason for termination. Implications of our findings are discussed with respect to policy concerns related to hiring, retention, productivitv, and staff development.

An asymptotic expression for the dielectric tensor e of a hot magnetized plasma is obtained employing the steepest descents method, via the transformation of the components of ε into their integral representation. The electrostatic Bernstein dispersion relation for oblique and perpendicular propagation is discussed under this treatment. It is shown that with this procedure the computation of the dispersion relation is up to 20 times faster when it is compared with the original expression, and the relative accuracy is usually as good as O·l% for a typical case.

The authors examine the extent and nature of mental health coverage within health maintenance organizations. Information was gathered on staffing and referral patterns, service location, and planning and administration of mental health services within health maintenance organizations. Findings from this national survey help clarify the present extent to which mental health services are integrated within health maintenance organizations in the context of the growing importance of health maintenance organizations as an alternative health care delivery system.

A national sample of short-term hospitals is examined for differences in implementation of five innovative health programs. Findings are analyzed to differentiate the effects of selected demographic and organiTational variables. Greater implementation is associated with large voluntary hospitals, hospitals located in metropolitan areas, and those located in the Northeastern states. Differential implementation patterns through time are shown to be well developed only for rehabilitation services. For all program areas, implementation rates approximate the normal diffusion curve. DURING THE PAST DECADE there has been growing interest in maximizing the effectiveness and efficiency of the health care system. This concern has resulted in increasing attention to innovation and to factors underlying the implementation and acceptance of new programs and methods of delivering health care.t

Procaine penicillin (procaine benzylpenicillin) given from the first day after hatching to slaughter led to a total increase in output of 11 and 15.4% respectively in two trials on different strains of table cockerels. The improved yield was partly due to improved growth and partly to a reduction in cull rate. Penicillin improved food-conversion up to seven weeks of age, but this advantage was no longer evident at 15 weeks.

The degree to which mental health services and coverage have been integrated into prepaid health plans (PHPs) on a national level is unknown. Using two self-administered mail questionnaires, the authors obtained descriptive data on the organization and delivery of mental health services within 205 PHPs throughout the United States and Guam. After discussing the growth of PHPs in the United States and the development of prepaid mental health services, the authors analyze the survey data using the PHP as the unit of analysis. Although 94 percent of the PHPs in the survey offered mental health benefits as part of their basic health plan, the authors found that the varied organizational characteristics of both the PHPs and their mental health components may have affected the specific mental health services provided as well as their costs, utilization, and referral patterns. The authors believe that further analysis of the various PHP organizational models is necessary to understand the utilization and costs of prepaid mental health services.

This 1982 national survey of all operational health maintenance organizations (HMOs) provides information on the current status of mental health services, benefits, costs, and utilization within HMOs, updating and augmenting a 1978 study. Approximately 94 per cent of the responding HMOs offered mental health service coverage; over one-half (54 per cent) offered alcohol and drug abuse service coverage. The present coverage benefits and utilization of mental health services within HMOs continue to reflect greater variability vis-a-vis other health services within HMOs. Over one-half (57 per cent) of the HMOs provided for 30 days of inpatient mental health coverage (per member per year). Three out of four (77 per cent) of the health plans provided for 20 ambulatory visits (per member per year). The mean mental health hospital utilization rate was 32 days (per 1,000 members per year). The mean mental health ambulatory utilization rate was 0.33 encounters (per member per year). Further studies should investigate the combined influence of organization characteristics, mental health service organization characteristics, and service benefits on the costs and utilization of HMO mental health services.

1) Training experience is closely related to whether or not handicapped children are treated. If practitioners attended a postgraduate pedodontic training program, or received classroom education or clinical training in the treatment of handicapped children, they are much more likely to treat such patients. (Worth noting is the fact that one fourth of the pedodontists treating handicapped children had not received postgraduate pedodontic training and 20-30 percent reported no training on the treatment of such patients at all.) 2) Slightly less than half of the general practitioners and 96 percent of the pedodontists surveyed report that they currently treat the dental problems of handicapped children. 3) Practitioners currently treating handicapped children report treating more such patients during their dental training and are more likely to feel that they received sufficient exposure to these patients during their training. (Twenty percent of the general practitioners and 53 percent of the pedodontists felt they had sufficient exposure.) 4) Dentists treating handicapped children were more likely to report both classroom education and clinical training about the use of multidisciplinary health manpower in the treatment of their patients, and to report using such personnel as consultants in their dental practice.

This study reports the results of a 1986 national survey of mental health, alcohol, and substance abuse services within health maintenance organizations in the United States. Ninety-seven percent of responding health maintenance organizations (HMOs) offered mental health service coverage and two-thirds of responding HMOs offered alcohol and substance abuse service coverage. Annual mean mental health hospitalization was 36.90 days per 1,000 members and annual mean ambulatory mental health utilization was 0.29 physician encounters per member.

Laminaria tents have proved to be an extremely useful adjunct to the performance of therapeutic abortion. Their use has markedly decreased the discomfort of mechanical cervical dilatation, and has facilitated the performance of first-trimester abortion without hospitalization. In 1,000 instances of laminaria use there were no uterine perforations and only four cervical lacerations. In four patients a false passage was created at the time of insertion, which was recognized at the time of curettage. Immediate and delayed postabortal complication rates compared favorably with prelaminaria data and the tents may be safely reused after ethylene oxide gas sterilization.

This 1978 national survey of all operating Health Maintenance Organizations (HMOs) provided information on the current status of mental health services utilization and service coverage within HMOs. It achieved a 68 per cent response rate. Approximately 90 per cent (108) of the HMOs offered mental health services through basic or supplemental coverage plans; HMO organization characteristics reflected relative heterogeneity; the mean monthly costs for basic health plan coverage (physical and mental health services) were $33.85 (for individuals) and $95.15 (for families); HMOs reported lower physical and mental health hospital utilization and higher ambulatory utilization when compared to more traditional forms of health insurance coverage. The present coverage and uitlization of mental health services within HMOs reflect greater variability of benefits and utilization within HMOs. There is need for further studies of mental health utilization in relation to organizational structure and delivery pattern relationships within HMOs.

Physalaemin and eledoisin and perhaps substance P belong to a group of peptides having similar pharmacological actions (Bertaccini et al., 1965a,b) both in vitro and in vivo. In vivo, these peptides affect the systemic arterial blood pressure in a similar way, but physalaemin is two to four times more active than eledoisin in decreasing blood pressure in dogs and increasing it in chickens. As previously reported, both the increase of blood flow and the ypotension provoked by eledoisin in several animal species, including man, could be explained by the peripheral vasodilating property of this peptide. Therefore, since physalaemin seemed to be closely related to eledoisin, we decided to investigate the peripheral vascular effects of physalaemin as well. In addition, since we had no data for proving whether the dilator action of eledoisin on vascular beds was a direct or an indirect action via the peripheral nervous system, we performed experiments on denervated vascular beds and made comparisons with other vasodilator drugs.