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.

Unilateral soft palate palsy secondary to blunt neck trauma: a case report

Unilateral soft palate paralysis is rare. No cases of unilateral soft palate paralysis with associated velopharyngeal insufficiency (VPI) secondary to minor blunt neck trauma have been reported to date. This case details the presentation of a man with isolated unilateral soft palate paralysis and associated velopharyngeal insufficiency following a collision with an opponent when playing soccer.

HIV infection and risk factors among the armed forces personnel stationed in Kinshasa, Democratic Republic of Congo

Despite recent declines in HIV incidence, sub-Saharan Africa remains the most heavily affected region in the global HIV/AIDS epidemic. Estimates of HIV prevalence in African military personnel are scarce and inconsistent. We conducted a serosurvey between June and September 2007 among 4043 Armed Forces personnel of the Democratic Republic of Congo (FARDC) stationed in Kinshasa, Democratic Republic of Congo (DRC) to determine the prevalence of HIV and syphilis infections and describe associated risk behaviours. Participants provided blood for HIV and syphilis testing and responded to a demographic and risk factor questionnaire. The prevalence of HIV was 3.8% and the prevalence of syphilis was 11.9%. Women were more likely than men to be HIV positive, (7.5% vs. 3.6% respectively, aOR: 1.66, 95% C.I: 1.21-2.28, p < 0.05). Factors significantly associated with HIV infection included gender and self-reported genital ulcers in the 12 months before date of enrollment. The prevalence of HIV in the military appears to be higher than the general population in DRC (3.8% vs. 1.3%, respectively), with women at increased risk of infection.

Assembly of high-areal-density deuterium-tritium fuel from indirectly driven cryogenic implosions

The National Ignition Facility has been used to compress deuterium-tritium to an average areal density of ~1.0±0.1 g cm(-2), which is 67% of the ignition requirement. These conditions were obtained using 192 laser beams with total energy of 1-1.6 MJ and peak power up to 420 TW to create a hohlraum drive with a shaped power profile, peaking at a soft x-ray radiation temperature of 275-300 eV. This pulse delivered a series of shocks that compressed a capsule containing cryogenic deuterium-tritium to a radius of 25-35 μm. Neutron images of the implosion were used to estimate a fuel density of 500-800 g cm(-3).

Tacrolimus-induced pain syndrome in a pediatric orthotopic liver transplant patient

Post-transplant complications are common among patients receiving immunosuppressive medications, including pain syndromes. Recently, a pain syndrome, calcineurin-inhibitor induced pain syndrome (CIPS) has been described. To our knowledge, this article is the second report of tacrolimus-associated CIPS, and the first report in the pediatric setting.

Hepatic progenitors and strategies for liver cell therapies

Liver cell therapies, including liver cell transplantation and bioartificial livers, are being developed as alternatives to whole liver transplantation for some patients with severe liver dysfunction. Hepatic progenitors are proposed as ideal cells for use in these liver cell therapies given their ability to expand extensively, differentiate into all mature liver cells, have minimal immunogenicity, be cryopreservable, and reconstitute liver tissue when transplanted. We summarize our ongoing efforts to develop clinical programs of hepatic progenitor cell therapies with a focus on hepatic stem cell biology and strategies that have emerged in analyzing that biology.

Quick splint for acute boutonniére injuries

Injuries to the proximal interphalangeal (PIP) joint are common in athletes, especially in contact and ball sports(1). Most PIP injuries involve disruption of the volar plate or dorsal dislocation. Less common is the "boutonniére" injury, which, if left undiagnosed and untreated, results in a boutonniére deformity. This deformity is difficult to manage and often requires prolonged immobilization and/or surgery to regain function(2).

Trace metals in ancient hair from the Karluk Archaeological Site, Kodiak, Alaska

Considerable interest exists in characterizing the extent of changes in methylmercury exposures from preindustrial to modern-day times. Hair is often preserved over centuries and has been useful in determining the extent of dietary trace metal exposures, particularly methylmercury. We examined 16 human hair samples taken from human hair bundles buried in the soil of the Karluk One Archaeological site located near the current Karluk village on the Kodiak Archipelago of Alaska. Hair samples were analyzed for total mercury, methylmercury, selenium, and cadmium. The mean total mercury level was 1.33 ppm (SD = 1.09). The mean methylmercury level, however, was considerably lower than the total mercury concentration: the mean methylmercury level was 0.03 ppm (SD = 0.02). The mean cadmium level was 0.15 ppm (SD = 0.14) and the mean selenium level was 5.22 ppm (SD = 5.73). While the concentration of total mercury in the Karluk hair samples is comparable to those observed in ancient hair from other locations, direct methylmercury quantization demonstrated that methylmercury levels were less than 2% of the total mercury in these hair samples. Because the hair was subjected to a variety of environmental influences over the centuries, the possibility of degradation of methylmercury in the hair over the last 400 to 800 years cannot be ruled out. The use of hair from remains found in more protected frozen or dry environments may provide the best evidence for the extent of preindustrial exposures to methylmercury and other trace metals.

A statewide, population-based, time series analysis of access to liver transplantation

While the number of patients listed for liver transplant has increased, the pool of donor organs has remained constant. Questions have arisen regarding equitable access to organs. The purpose of this study was to analyze factors associated with access to liver transplantation (LT) using a large, population-based, hospital discharge database. The primary hypothesis was that a variety of factors other than medical need could be associated with access to LT. The rate of LT was defined as the number of liver transplants per admission for liver disease. The data sources were selected to allow a population-based, time-series analysis of all patients admitted with liver disease and those receiving liver transplants in all 157 nonfederal hospitals in North Carolina from 1988 to 1993. The hypotheses of this study were that age, gender, payment source, type of liver disease, distance from the transplant center, and rural county of residence were associated with patients' likelihood of access to LT. During the six years studied, 56,803 patients were admitted with liver disease and 126 underwent liver transplantation (LT). The rate of LT increased from 0.07% to 0.27%. Age, gender, source of payment, type of liver disease, rural county of residence, and distance of residence from the transplant center were associated with rates of transplantation. In the multivariate model, source of payment appeared to have the strongest association with the likelihood of LT. These findings raise important questions associated with equitable access to health care, need for physician education, and transplant center regionalization.

Liver transplantation for alcoholic liver disease

Orthotopic liver transplantation (OLT) for individuals with alcoholic liver disease (ALD) remains controversial. This review was designed to evaluate the survival, recidivism, and rehabilitation of the alcoholic liver transplant recipient in a single transplant center.

METHODS

Between 10/86 and 11/92 203 liver transplants were performed in 179 patients. In 42 patients (23%) the primary etiologic diagnosis was ALD (36 males, 6 females, median age 47 yr). All ALD patients were evaluated preoperatively by social service, psychiatry, and medical psychology, in addition to hepatology and transplant surgery. A minimum abstinence period of 3-6 months was encouraged, although exceptions were made for cases of extreme medical urgency in which a good prognosis for abstinence was predicted.

RESULTS

In OLT recipients with ALD, actuarial survival at 1, 2, and 3 yr was 74%, 71%, and 71%, respectively, compared to 71%, 71%, and 69% for all OLT recipients. One- and two-year survival was 85% in the most recently transplanted 86 patients, 20 of whom (23%) had ALD with 1- and 2-yr survival of 84% (N.S.). Recidivism was monitored postoperatively by interviews with the patient and family, supplemented by random urine and serum toxicology. Of the 29 survivors, 2 (7%) returned temporarily to alcohol use but are presently abstinent. Although none of the ALD patients in this study was able to work prior to OLT, 76% of the survivors at least 4 months post-transplantation were employed.

CONCLUSIONS

Although our experience is small, our results suggest that OLT is appropriate therapy for carefully selected patients with end-stage liver failure due to ALD. The multi-disciplinary approach to preoperative evaluation of the alcoholic liver transplant candidate is effective in determining those patients committed to abstinence after a successful transplant.

A new percutaneous technique for establishing venous bypass access in orthotopic liver transplantation

Partial veno-venous bypass (VVB) is commonly used in orthotopic liver transplantation (OLT). Venous access for blood return during VVB classically uses a surgical cutdown on the left axillary vein (LAV), which may prolong operating time and can be associated with significant complications. The authors have developed an alternative means of establishing venous access whereby the anesthesia team places 8.5F venous cannulae preoperatively in one or two vessels (internal jugular, antecubital, or subclavian) percutaneously using the Seldinger technique. These cannulae then serve to accept venous return from below the diaphragm via a centrifugal pump. The aim fo the present study was to compare the hemodynamic profiles obtained during the anhepatic phase of OLT in patients in whom either a conventional LAV catheter (group 1) or percutaneous catheters (group 2) were used for return flow from a centrifugal pump. There were no identifiable complications related to venous access in either group of patients. Total operating room time was 800 +/- 30 minutes in group 1 and 720 +/- 40 minutes in group 2 (P = 0.17). Hemodynamic parameters were determined from continuous strip chart recordings of arterial, right atrial, and inferior vena caval (IVCP) pressures. Cardiac output (CO) was measured by thermodilution whereas pump flow was determined by an electromagnetic probe. Renal perfusion pressure (RPP) was calculated as the difference between mean arterial pressure (MAP) and IVCP. Bypass pump flow was greater, but not significantly different between group 1 (3.0 +/- 0.2 L/min) and group 2 (2.4 +/- 0.2 L/min) (P = 0.09).(ABSTRACT TRUNCATED AT 250 WORDS)

Factor XI deficiency acquired by liver transplantation

Factor XI deficiency (the Rosenthal syndrome), an autosomal recessive genetic defect, was transmitted to a patient after orthotopic liver transplantation. The deficiency was manifested by an isolated prolonged activated partial thromboplastin time (aPTT) after surgery. Hematologic evaluation using specific factor analysis revealed an absolute deficiency of factor XI. Stored serum obtained from the organ recipient before transplantation showed normal factor XI levels. When the liver donor's family was questioned, it was discovered that he was of Ashkenazi Jewish descent and that he had a history of bleeding after dental procedures. Before his death from intracerebral bleeding, he was documented to have an isolated prolonged aPTT value. This case shows that potentially morbid genetic defects can be transmitted by organ transplantation. It also provides evidence confirming that the liver is the only site of factor XI production.

Reduction of morbidity and mortality from biliary complications after liver transplantation

Over a 4-yr period that began October 1, 1986, 103 orthotopic liver transplants were performed on 91 patients at the Johns Hopkins Hospital. Biliary reconstruction at the time of transplantation was performed in standard fashion by an appropriately trained member of the surgical team. Six (7%) patients developed biliary complications, which included three cases of common bile duct stricture and one case each of bile duct obstruction caused by biopsy-related hemobilia, biloma and a retained fragment of a T tube after removal. Five of the six patients were treated successfully by nonoperative interventional radiological procedures performed under local anesthesia with light intravenous sedation. Reoperative surgery (to remove the T-tube fragment from subcutaneous tissue) was required for only one patient, and no deaths (0 of 91) were attributable to biliary complications. All six patients are alive and well 6 to 33 mo after the operation with excellent liver function. Our findings would suggest that most biliary complications of orthotopic liver transplants are avoidable and that the few that do appear can usually be managed both safely and effectively by an interventional radiological approach.

Exercise management

Aerobic exercise is receiving increasing emphasis as an important health promoting behavior. This paper provides a model for assessment and management of the healthy exercising adult. A data base is presented that enables the practitioner to determine the presence of risk factors and/or disease, to identify health problems which might modify exercise prescription and to collect information to individualize the prescription. The remainder of the paper details the elements of exercise prescription with a specific focus on patient education.