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.

Investigation and management of prosthetic joint infection in knee replacement: A BASK Surgical Practice Guideline

BACKGROUND

The burden of knee replacement prosthetic joint infection (KR PJI) is increasing. KR PJI is difficult to treat, outcomes can be poor and it is financially expensive and limited evidence is available to guide treatment decisions.

AIM

To provide guidelines for surgeons and units treating KR PJI.

METHODS

Guideline formation by consensus process undertaken by BASK's Revision Knee Working Group, supported by outputs from UK-PJI meetings.

RESULTS

Improved outcomes should be achieved through provision of care by revision centres in a network model. Treatment of KR PJI should only be undertaken at specialist units with the required infrastructure and a regular infection MDT. This document outlines practice guidelines for units providing a KR PJI service and sets out: CONCLUSIONS: KR PJI patients treated within the NHS should be provided the best care possible. This report sets out guidance and support for surgeons and units to achieve this.

Analysis of the use of fortified medium in continuous culture of mammalian cells

Continuous culture is frequently used in the cultivation of mammalian cells for the manufacturing of recombinant protein pharmaceuticals. In such operations a large volume of medium is turned over each day, especially in the case where cell recycle, or perfusion cultivation, is practiced. In principle, the volumetric throughput of medium can be reduced by using a more concentrated feed while maintaining the same nutrient provision rate. Overall, the medium components are divided into two categories: 'consumable nutrients' and 'unconsumable inorganic bulk salts'. In such fortified medium, the concentrations of consumable nutrients, but not bulk salts, are increased. With a stoichiometrically-balanced medium, the large amount of nutrients fed into the culture is largely consumed by cells to give rise to residual concentrations of these nutrients in their optimal range. However, unless care is taken to initiate the continuous culture, overshoot of nutrients may occur during the transient period. The high nutrient concentration during overshoot may be inhibitory by itself, or the resulting high osmolality may retard the growth. Using a mathematical model that incorporates the growth inhibitory effect of high osmolality we demonstrate such a potentially catastrophic effect of nutrient and osmolality overshoot by simulation. To avoid overshoot a controlled nutrient feeding scheme should be devised at the initiation of continuous culture.

The influence of postoperative coronal alignment on revision surgery in total knee arthroplasty

This study examines the association between postoperative coronal tibiofemoral alignment and revision surgery in knee arthroplasty. We retrospectively reviewed the case notes and post-operative long-leg radiographs of 197 Kinemax knee arthroplasty with mean follow-up of 9 years (SD 2.2). They were divided into three groups: neutral, valgus and varus. Revision or decision to revise was used as a hard endpoint. There was no statistical difference among the three groups (p=0.78). We conclude that aseptic failure of a total knee is multifactorial. Coronal tibio-femoral alignment may not be as important a cause of failure as has been previously thought.

Survivorship analysis of 3234 primary knee arthroplasties implanted over a 26-year period: a study of eight different implant designs

We conducted a survivorship analysis of 3234 primary total knee replacements performed at our hospital between 1969 and 1995. Each knee replacement was entered once only. Revision was defined as the end point. Data were collected both from patient records and by postal questionnaire. Eight types of knee prostheses were evaluated with best-case and worst-case scenarios compared over a 5-, 10- and 15-year period. The evidence suggests that the "Condylar type devices" which include the Total Condylar, Press Fit Condylar (PFC), Kinematic, Kinemax and Anatomic Modular Knee (AMK) have very similar survivorship curves and in the main have performed well up to a 10-year period. The LCS mobile bearing knee performed well at 5 years. The earlier design prostheses had a poor result in terms of survivorship and are hence were discontinued.

Ulnopalmar dislocation of the fifth carpometacarpal joint. A rare injury

Volar dislocation of the carpometacarpal joint of the little finger is an uncommon injury. It is subdivided in ulnopalmar and radiopalmar dislocations. The injury can easily be missed on standard x-rays. Closed reduction and K-wire fixation has commonly been used in the treatment, although closed reduction and casting has been reported. Only 10 cases of an ulnopalmar dislocation were published previously. We report a case of a simultaneous dislocation of the 4th metacarpophalangeal joint and an ulnopalmar dislocation of the 5th carpometacarpal joint. The combination of these injuries has not been reported yet. We review the available literature and discuss the methods of treatment.

Chronic sialadenitis with pleomorphic adenoma of the parotid: coincidental or causal?

A 12-year-old boy with a pleomorphic adenoma of the parotid is reported. The excised gland specimen also showed evidence of chronic sialadenitis. The co-existence of these two entities has not been previously reported in the literature surveyed by us. The authors feel that the two conditions may have a common underlying etiology.

Does temporary clamping of drains following knee arthroplasty reduce blood loss? A randomised controlled trial

In a randomised, blinded study 76 patients undergoing primary total knee arthroplasty were assigned to either immediate drain opening (n = 45) or drains opened at 2 h (n = 31). No significant differences were found between the groups for the volume of drained blood, transfusion requirements, knee motion or wound status. The authors conclude that the practice of clamping drains has no benefit in routine knee arthroplasty. However, when faced with immediate brisk blood loss, the results suggest that drains can be clamped without any excess morbidity.

Characterization of DNA immobilized on electrochemically prepared conducting polypyrrole-polyvinyl sulfonate films

The article describes the adsorption characteristics of DNA onto electrochemically generated polypyrrole-polyvinyl sulfonate (PPY-PVS) films obtained as a function of pH. Adsorption on PPY doped with an anion proceeds by anion exchange, and since DNA possesses a fixed negative charge owing to PO4-, it favors a very strong binding displacing PVS with favorable energetic interactions. Characterization of adsorbed DNA onto the PPY-PVS films was carried out by ultraviolet-visible, Fourier transform infrared spectroscopy, and cyclic voltammetric studies.

Preparation and characterization of poly-N-vinyl carbazole Langmuir-Blodgett films

Langmuir monolayers of poly-N-vinyl carbazole (PNVK) were obtained by dispensing PNVK dissolved in tetrahydrofuran onto an air-water interface. Surface pressure-area isotherms of mixed monolayer of the PNVK were studied under different subphase conditions such as temperature and pH of the subphase. It was demonstrated that the monolayer of PNVK remained stable over a temperature range of 10-40 degrees C. The area per molecule of the solid phase was found to be 31 A2. These monolayers were transferred onto indium-tin-oxide-coated glass plates and characterized by spectroscopic and electrochemical techniques.

Coimmobilization of urease and glutamate dehydrogenase in electrochemically prepared polypyrrole-polyvinyl sulfonate films

Immobilization of urease and glutamate dehydrogenase enzymes in electrochemically prepared polypyrrole-polyvinyl sulfonate films (PPY-PVS) was carried out using physical adsorption and electrochemical entrapment techniques. Detailed studies on optimum pH, Fourier transform infrared spectroscopy, cyclic voltammetry, and scanning electron microscopy of the enzymes in the immobilized state were conducted. The value of the apparent Michaelis-Menten constant was experimentally determined to be 2.5 and 2.7 for physically adsorbed and electrochemically entrapped urease in PPY-PVS films, respectively.

Cybernetic modeling and regulation of metabolic pathways in multiple steady states of hybridoma cells

Hybridoma cells utilize a pair of complementary and partially substitutable substrates, glucose and glutamine, for growth. It has been shown that cellular metabolism shifts under different culture conditions. When those cultures at different metabolic states are switched to a continuous mode, they reach different steady states under the same operating conditions. A cybernetic model was constructed to describe the complementary and partial substitutable nature of substrate utilization. The model successfully predicted the metabolic shift and multiple steady-state behavior. The results are consistent with the experimental observation that the history of the culture affects the resulting steady state.

Lipoblastoma of the neck

Lipoblastoma and lipoblastomatosis are benign tumours arising from embryonal fat cells. These rare tumours essentially occur in infancy and early childhood. The males are affected more than females often in the ratio of 3:1. These tumours usually arise in extremities. The involvement of neck is rare with only 10 cases reported so far in English literature. We herein report lipoblastoma of the neck in a 3 year old girl.

Multiple steady states with distinct cellular metabolism in continuous culture of mammalian cells

Mammalian cells have the ability to proliferate under different nutrient environments by utilizing different combinations of the nutrients, especially glucose and the amino acids. Under the conditions often used in in vitro cultivation, the cells consume glucose and amino acids in great excess of what is needed for making up biomass and products. They also produce large amounts of metabolites with lactate, ammonia, and some non-essential amino acids such as alanine as the most dominant ones. By controlling glucose and glutamine at low levels, cellular metabolism can be altered and can result in reduced glucose and glutamine consumption as well as in reduced metabolite formation. Using a fed-batch reactor to manipulate glucose at a low level (as compared to a typical batch culture), cell metabolism was altered to a state with substantially reduced lactate production. The culture was then switched to a continuous mode and allowed to reach a steady-state. At this steady-state, the concentrations of cells and antibody were substantially higher than a control culture that was initiated from a batch culture without first altering cellular metabolism. The lactate and other metabolite concentrations were also substantially reduced as compared to the control culture. This newly observed steady-state was achieved at the same dilution rate and feed medium as the control culture. The paths leading to the two steady-states, however, were different. These results demonstrate steady-state multiplicity. At this new steady-state, not only was glucose metabolism altered, but the metabolism of amino acids was altered as well. The amino acid metabolism in the new steady-state was more balanced, and the excretion of non-essential amino acids and ammonia was substantially lower. This approach of reaching a more desirable steady-state with higher concentrations of cells and product opens a new avenue for high-density- and high-productivity-cell culture.

Electrostatic properties of membranes containing acidic lipids and adsorbed basic peptides: theory and experiment

The interaction of heptalysine with vesicles formed from mixtures of the acidic lipid phosphatidylserine (PS) and the zwitterionic lipid phosphatidylcholine (PC) was examined experimentally and theoretically. Three types of experiments showed that smeared charge theories (e.g., Gouy-Chapman-Stern) underestimate the membrane association when the peptide concentration is high. First, the zeta potential of PC/PS vesicles in 100 mM KCl solution increased more rapidly with heptalysine concentration (14.5 mV per decade) than predicted by a smeared charge theory (6.0 mV per decade). Second, changing the net surface charge density of vesicles by the same amount in two distinct ways produced dramatically different effects: the molar partition coefficient decreased 1000-fold when the mole percentage of PS was decreased from 17% to 4%, but decreased only 10-fold when the peptide concentration was increased to 1 microM. Third, high concentrations of basic peptides reversed the charge on PS and PC/PS vesicles. Calculations based on finite difference solutions to the Poisson-Boltzmann equation applied to atomic models of heptalysine and PC/PS membranes provide a molecular explanation for the observations: a peptide adsorbing to the membrane in the presence of other surface-adsorbed peptides senses a local potential more negative than the average potential. The biological implications of these "discreteness-of-charge" effects are discussed.

Alteration of cellular metabolism by consecutive fed-batch cultures of mammalian cells

The metabolism of myeloma cells was altered to reduce lactate production in consecutive fed-batch cultures. The glucose concentration was maintained at low levels (0.28-0.55 mM) by employing a dynamic nutrient feeding method based on on-line measurement of the oxygen uptake rate (OUR) to estimate the metabolic demand of the cells. This strategy has been previously reported to be applied to cultures of hybridoma cells, in which the production of lactate was significantly reduced by thus maintaining the glucose concentration at low levels. However, for this cell line, a single fed-batch culture was not sufficient to alter the cellular metabolism, even at a glucose concentration of 0.28 mM. Two consecutive fed-batch cultures were employed to ensure that the cells were cultivated under a low glucose concentration for a sufficiently prolonged period of time to allow a switch of the cellular metabolism from a glycolytic (high lactate production) to oxidative (low lactate production) state.

Omphalopagus parasite: a rare congenital anomaly

Omphalopagus parasite is a very rare congenital anomaly. Presented here is a case in which an extra truncus was attached to an infant in the region of the epigastrium. The truncus had well-formed extremities, an abdomen, and a hypoplastic thorax. The infant had a small omphalocoele in addition to the truncus. Surgery performed in the neonatal period helped to achieve a successful separation of the truncus from the host.

The problem of transition from the chemical to the biological evolution: some possible solutions

On the basis of evidence that several low-molecular-weight substances as well as enzymes are compartmentalised within the so-called soluble phase of the cell, and other considerations, it is argued that DNA may not contain information for certain types of organisation found in living cells. It may be necessary for a cell to possess the "non-DNA-controlled" organisation for performance of its minimum functions; such organisation would then also serve as a "template" for its appearance in the daughter cell. The problem of transition from chemical to biological evolution (that is, the formation of the "first cell") may be essentially the problem of emergence of such intracellular organisation for which information may not reside in DNA. Two possible mechanisms through which this may have happened are stated.