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Background: The hemostatic net has been promoted as a safe and effective method to prevent hematoma formation following facelift procedures. To date there is little published evidence to validate the replicability and effectiveness of the technique., Objectives: This study presents 2 cohorts of facelift patients from a single surgeon's practice to assess the impact of the hemostatic net on hematoma formation., Methods: The records of 304 patients were reviewed on whom the hemostatic net was placed following a facelift between July 2017 and October 2022. Data were collected and assessed for complications and compared with a control group of 359 patients who underwent a facelift procedure without placement of a hemostatic net by the same surgeon between 1999 and 2004., Results: A total of 663 patients were included. In this retrospective cohort study, analysis of available data showed a significantly reduced hematoma rate of 0.6% in the intervention group compared with 3.9% in the control group (P = .006722)., Conclusions: The use of the hemostatic net is a safe, reproducible, and effective technique in reducing the risk of hematoma in facelift surgery., (© The Author(s) 2023. Published by Oxford University Press on behalf of The Aesthetic Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: Extracorporeal shock wave therapy (ESWT) represents a promising, non-invasive management strategy supporting the treatment of a variety of conditions related to plastic surgery., Objectives: This literature review aimed to give a systematic overview of current applications, its mechanism of action, and its potential to provide tangible therapies in plastic surgery., Methods: The databases PubMed (National Institute of Health, Bethesda, MD), Embase (via Ovid [Elsevier, Amsterdam, the Netherlands]), and the Cochrane Library (Cochrane, London, UK) were searched for articles published up to June 1, 2021. Clinical studies of any design including ESWT in the context of plastic surgery were included. Two reviewers extracted data, and 46 articles were analyzed after application of the inclusion and exclusion criteria., Results: Forty-six included studies (n = 1496) were categorized into the following broad themes: cellulite/body contouring/skin rejuvenation, burns/scar treatment, diabetic foot ulcers/chronic wound, and future perspectives of ESWT. Overall, applications of ESWT were heterogenous, and the majority of studies reported effectiveness of ESWT as an alternative treatment technique. Flawed methodology and differences in technical standards limit the outcome and conclusion of this review., Conclusions: There is yet insufficient evidence to support the effectiveness of any specific intervention included in this review; however, all included studies reported improvements in key outcomes. Where reported, ESWT displayed a good safety profile with no serious adverse events. Further research is needed to provide more evidence to delineate the indications of ESWT in plastic surgery., (© The Author(s) 2022. Published by Oxford University Press on behalf of The Aesthetic Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Objective: Fat necrosis (FN) is a well-known complication in plastic surgery. Excision of symptomatic FN has been the gold standard, but it often results in contour irregularities that require subsequent treatment. Different alternative surgical and nonsurgical management strategies have been described; however, there are currently no guidelines. This literature review aims to provide an overview of available treatment options and current management standards to support clinical decision making., Method: A literature search in the databases PubMed, Embase (via Ovid), and Web Of Science was carried out to identify eligible articles. The search strategy included combinations of the following terms: "Fat necrosis "AND (treatment OR management OR therapy). Six articles discussing or reporting management strategies of FN in a plastic surgery context were included., Results: A variety of techniques were used to manage symptomatic FN. Asymptomatic or small lesions can be treated conservatively. Oil cyst and moderately sized areas of symptomatic FN can effectively be treated by aspiration, ultrasound-assisted liposuction, or needle aeration. Calcified and large areas of FN require excision and debridement of necrotic fat tissue CONCLUSION: At present, there is no consensus on the management of symptomatic FN. The authors propose a new classification system to aid the guidance of management of symptomatic FN., (Copyright © 2022 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.)

Epitaxial graphene has proven itself to be the best candidate for quantum electrical resistance standards due to its wide quantum Hall plateaus with exceptionally high breakdown currents. However one key underlying mechanism, a magnetic field dependent charge transfer process, is yet to be fully understood. Here we report measurements of the quantum Hall effect in epitaxial graphene showing the widest quantum Hall plateau observed to date extending over 50 T, attributed to an almost linear increase in carrier density with magnetic field. This behaviour is strong evidence for field dependent charge transfer from charge reservoirs with exceptionally high densities of states in close proximity to the graphene. Using a realistic framework of broadened Landau levels we model the densities of donor states and predict the field dependence of charge transfer in excellent agreement with experimental results, thus providing a guide towards engineering epitaxial graphene for applications such as quantum metrology.

We report time-of-flight measurements on electrons traveling in quantum Hall edge states. Hot-electron wave packets are emitted one per cycle into edge states formed along a depleted sample boundary. The electron arrival time is detected by driving a detector barrier with a square wave that acts as a shutter. By adding an extra path using a deflection barrier, we measure a delay in the arrival time, from which the edge-state velocity v is deduced. We find that v follows 1/B dependence, in good agreement with the E[over →]×B[over →] drift. The edge potential is estimated from the energy dependence of v using a harmonic approximation.

Experimental evidence from both spin-valve and quantum transport measurements points towards unexpectedly fast spin relaxation in graphene. We report magnetotransport studies of epitaxial graphene on SiC in a vector magnetic field showing that spin relaxation, detected using weak-localization analysis, is suppressed by an in-plane magnetic field B(∥), and thereby proving that it is caused at least in part by spinful scatterers. A nonmonotonic dependence of the effective decoherence rate on B(∥) reveals the intricate role of the scatterers' spin dynamics in forming the interference correction to the conductivity, an effect that has gone unnoticed in earlier weak localization studies.

Energy relaxation of hot Dirac fermions in bilayer epitaxial graphene is experimentally investigated by magnetotransport measurements on Shubnikov-de Haas oscillations and weak localization. The hot-electron energy loss rate is found to follow the predicted Bloch-Grüneisen power-law behaviour of T(4) at carrier temperatures from 1.4 K up to ∼100 K, due to electron-acoustic phonon interactions with a deformation potential coupling constant of 22 eV. A carrier density dependence n(e)(-1.5) in the scaling of the T(4) power law is observed in bilayer graphene, in contrast to the n(e)(-0.5) dependence in monolayer graphene, leading to a crossover in the energy loss rate as a function of carrier density between these two systems. The electron-phonon relaxation time in bilayer graphene is also shown to be strongly carrier density dependent, while it remains constant for a wide range of carrier densities in monolayer graphene. Our results and comparisons between the bilayer and monolayer exhibit a more comprehensive picture of hot carrier dynamics in graphene systems.

We study an epitaxial graphene monolayer with bilayer inclusions via magnetotransport measurements and scanning gate microscopy at low temperatures. We find that bilayer inclusions can be metallic or insulating depending on the initial and gated carrier density. The metallic bilayers act as equipotential shorts for edge currents, while closely spaced insulating bilayers guide the flow of electrons in the monolayer constriction, which was locally gated using a scanning gate probe.

We demonstrate the energy- and time-resolved detection of single-electron wave packets from a clock-controlled source transmitted through a high-energy quantum Hall edge channel. A quantum dot source is loaded with single electrons which are then emitted ~150 meV above the Fermi energy. The energy spectroscopy of emitted electrons indicates that at high magnetic field these electrons can be transported over several microns without inelastic electron-electron or electron-phonon scattering. Using a time-resolved spectroscopic technique, we deduce the wave packet size at picosecond resolution. We also show how this technique can be used to switch individual electrons into different electron waveguides (edge channels).

In this paper, we review the recent extraordinary progress in the development of a new quantum standard for resistance based on graphene. We discuss the unique properties of this material system relating to resistance metrology and discuss results of the recent highest-ever precision direct comparison of the Hall resistance between graphene and traditional GaAs. We mainly focus our review on graphene expitaxially grown on SiC, a system which so far resulted in the best results. We also briefly discuss progress in the two other graphene material systems, exfoliated graphene and chemical vapour deposition graphene, and make a critical comparison with SiC graphene. Finally, we discuss other possible applications of graphene in metrology.

We report the phase space defined by the quantum Hall effect breakdown in polymer gated epitaxial graphene on SiC (SiC/G) as a function of temperature, current, carrier density, and magnetic fields up to 30 T. At 2 K, breakdown currents (I(c)) almost 2 orders of magnitude greater than in GaAs devices are observed. The phase boundary of the dissipationless state (ρ(xx)=0) shows a [1-(T/T(c))2] dependence and persists up to T(c)>45  K at 29 T. With magnetic field I(c) was found to increase ∝B(3/2) and T(c)∝B2. As the Fermi energy pproaches the Dirac point, the ν=2 quantized Hall plateau appears continuously from fields as low as 1 T up to at least 19 T due to a strong magnetic field dependence of the carrier density.

Single-electron pumps are set to revolutionize electrical metrology by enabling the ampere to be redefined in terms of the elementary charge of an electron. Pumps based on lithographically fixed tunnel barriers in mesoscopic metallic systems and normal/superconducting hybrid turnstiles can reach very small error rates, but only at megahertz pumping speeds that correspond to small currents of the order of picoamperes. Tunable barrier pumps in semiconductor structures are operated at gigahertz frequencies, but the theoretical treatment of the error rate is more complex and only approximate predictions are available. Here, we present a monolithic, fixed-barrier single-electron pump made entirely from graphene that performs at frequencies up to several gigahertz. Combined with the record-high accuracy of the quantum Hall effect and proximity-induced Josephson junctions, quantized-current generation brings an all-graphene closure of the quantum metrological triangle within reach. Envisaged applications for graphene charge pumps outside quantum metrology include single-photon generation via electron-hole recombination in electrostatically doped bilayer graphene reservoirs, single Dirac fermion emission in relativistic electron quantum optics and read-out of spin-based graphene qubits in quantum information processing.

Electron pumps generate a macroscopic electric current by controlled manipulation of single electrons. Despite intensive research towards a quantum current standard over the last 25 years, making a fast and accurate quantized electron pump has proved extremely difficult. Here we demonstrate that the accuracy of a semiconductor quantum dot pump can be dramatically improved by using specially designed gate drive waveforms. Our pump can generate a current of up to 150 pA, corresponding to almost a billion electrons per second, with an experimentally demonstrated current accuracy better than 1.2 parts per million (p.p.m.) and strong evidence, based on fitting data to a model, that the true accuracy is approaching 0.01 p.p.m. This type of pump is a promising candidate for further development as a realization of the SI base unit ampere, following a redefinition of the ampere in terms of a fixed value of the elementary charge.

We have performed magnetotransport measurements on monolayer epitaxial graphene and analyzed them in the framework of the disordered Fermi liquid theory. We have separated the electron-electron and weak-localization contributions to resistivity and demonstrated the phase coherence over a micrometer length scale, setting the limit of at least 50 ps on the spin relaxation time in this material.

We report the observation of nonadiabatic excitations of single electrons in a quantum dot. Using a tunable-barrier single-electron pump, we have developed a way of reading out the excitation spectrum and level population of the dot by using the pump current as a probe. When the potential well is deformed at subnanosecond time scales, electrons are excited to higher levels. In the presence of a perpendicular magnetic field, the excited states follow a Fock-Darwin spectrum. Our experiments provide a simple model system to study nonadiabatic processes of quantum particles.

The quantum Hall effect allows the international standard for resistance to be defined in terms of the electron charge and Planck's constant alone. The effect comprises the quantization of the Hall resistance in two-dimensional electron systems in rational fractions of R(K) = h/e(2) = 25,812.807557(18) Omega, the resistance quantum. Despite 30 years of research into the quantum Hall effect, the level of precision necessary for metrology--a few parts per billion--has been achieved only in silicon and iii-v heterostructure devices. Graphene should, in principle, be an ideal material for a quantum resistance standard, because it is inherently two-dimensional and its discrete electron energy levels in a magnetic field (the Landau levels) are widely spaced. However, the precisions demonstrated so far have been lower than one part per million. Here, we report a quantum Hall resistance quantization accuracy of three parts per billion in monolayer epitaxial graphene at 300 mK, four orders of magnitude better than previously reported. Moreover, by demonstrating the structural integrity and uniformity of graphene over hundreds of micrometres, as well as reproducible mobility and carrier concentrations across a half-centimetre wafer, these results boost the prospects of using epitaxial graphene in applications beyond quantum metrology.

Peritoneal macrophages from Toll-like receptor (TLR) 4-deficient ScCr mice produced less tumor necrosis factor, interleukin (IL)-1alpha, and IL-1beta than did macrophages of control mice, when stimulated with conidia, but not with hyphae, of Aspergillus fumigatus, a finding suggesting that TLR4-mediated signals are lost during germination. This hypothesis was confirmed by use of a TLR4-specific fibroblast reporter cell line (3E10) that responded to the conidia, but not to the hyphae, of A. fumigatus. In contrast, macrophages from TLR2-knockout mice had a decreased production of proinflammatory cytokines in response to both Aspergillus conidia and Aspergillus hyphae, and these results were confirmed in 3E10 cells transfected with human TLR2. In addition, Aspergillus hyphae, but not Aspergillus conidia, stimulated production of IL-10 through TLR2-dependent mechanisms. In conclusion, TLR4-mediated proinflammatory signals, but not TLR2-induced anti-inflammatory signals, are lost on Aspergillus germination to hyphae. Therefore, phenotypic switching during germination may be an important escape mechanism of A. fumigatus that results in counteracting the host defense.

Fulminant meningococcal sepsis (FMS) is considered the prototypical Gram-negative sepsis. Lipopolysaccharide (LPS) is thought to be the main toxic element that induces pro-inflammatory cytokine production after interaction with CD14 and toll-like receptor 4 (TLR4). However, there is increasing evidence that LPS is not the sole toxic element of meningococci. The aim of the present study was to determine the role of CD14 and TLR4 in pro-inflammatory cytokine induction by meningococci. To this end, cytokine induction by isolated meningoccal LPS, wild-type N. meningitidis H44/76 (LPS+-meningococci) matched for concentrations of LPS and LPS-deficient N. meningitidis H44/76lpxA (LPS - -meningococci) was studied in human PBMCs and murine peritoneal macrophages (PMs). Pre-incubation of PBMCs with WT14, a monoclonal antibody against CD14, abolished TNF-alpha and IL-1beta induction by E. coli LPS, while cytokine induction by meningococcal LPS was only partially inhibited. When LPS+- and LPS - -meningococci at higher concentrations were used as stimuli, anti-CD14 had a minimal effect. In C3H/HeJ murine PMs, devoid of a functional TLR4, minimal IL-1alpha, IL-6 and TNF-alpha production was seen after stimulation with 10 ng/mL E. coli or meningococcal LPS. However, at higher concentrations (1000 ng LPS/mL) the production of TNF-alpha, but not IL-1alpha or IL-6, occurred also independently of TLR4. The expression of a functional TLR4 in murine PMs had no effect on the cytokine induction by LPS+- or LPS - -meningococci. It is concluded that pro-inflammatory cytokine induction by N. meningitidis can occur independently of CD14 and TLR4.

An important stage in visual processing is the quantification of optical attributes of the outside world. We argue that the metrics used for this quantification are flexible, and that this flexibility is exploited to optimise the discriminative power of the metrics. We derive mathematical expressions for such optimal metrics and show that they exhibit properties resembling well-known visual phenomena. To conclude, we discuss some of the implications of flexible metrics for visual identification.

The bioavailability of lithium citrate syrup was compared with that of regular lithium carbonate tablets in 18 healthy male human volunteers. Blood samples were collected up to 48 h after dosing. Lithium serum concentrations were determined by means of AAS. The absorption rate following oral administration of the syrup was greater (tmax 0.8 h) than following administration of regular tablets (tmax 1.4 h). Maximum lithium serum concentrations, however, were only about 10 per cent higher after syrup dosing and serum concentrations resulting from syrup and tablets were almost superimposable from 2 h after dosing. The terminal half-life of lithium was found to be 22 h after syrup as well as after tablet dosing. No side-effects were observed during the study. The bioavailability of lithium from syrup relative to tablets was found to be bioequivalent with respect to the maximum lithium serum concentration and the extent of drug absorption (AUC).

The bioavailability of two prazosin formulations was studied in 12 healthy volunteers. 1 Subject left the study. Based on the statistical tests of the pharmacokinetic parameters of prazosin in 11 volunteers, such as t 1/2, Cmax, tmax and AUC, it could be concluded that both preparations had comparable bioavailabilities.

Diclofenac 100 mg suppository is well absorbed from the gastrointestinal tract of six human volunteers. Plasma concentrations of 4'-hydroxydiclofenac and diclofenac could be measured; the concentrations of the three other metabolites were below the detection limit of the HPLC analysis. The apparent half-lives of diclofenac and 4'-OH-diclofenac are, respectively 1.3 +/- 0.3 h and 4.3 +/- 1.0 h. When the t 1/2 values are derived from the renal excretion rate-time profiles, they are as follows: diclofenac 1.8 +/- 0.9 h, 3'-OH-, and 5-OH-diclofenac 2.3 +/- 1.0 h and 2.5 +/- 0.4 h, respectively, while those of 4'-OH- and 4',5-diOH-diclofenac are, respectively 3.6 +/- 0.5 h and 3.1 +/- 1.3 h. Diclofenac is excreted for 13.6 +/- 6.5%, its renal clearance (Clr) = 3.23 +/- 1.03 ml/min. The main metabolite excreted in the urine is 4'-OH-diclofenac (27.2 +/- 12% dose; Clr = 6.14 +/- 4.04 ml/min). The total body clearance of the parent drug and the apparent total body clearance of the main metabolite are similar, 28.0 +/- 11.9 l/h and 27.5 +/- 10.9 l/h.

In a three-week study, the metabolism of the bronchodilator theophylline and its major metabolites formed by C-8 oxidation (1,3-dimethyluric acid) and N-demethylation (3-methylxanthine and 1-methyluric acid) was investigated in two healthy volunteers. Metabolic studies were performed following intravenous infusion of a single 6 mg/kg dose of aminophylline. During Week 1, theophylline was given alone (blank period), and during Weeks 2 and 3 it was given during oral coadministration of ofloxacin and enoxacin, respectively. Dosage of each quinolone was 200 mg twice daily for four days, starting three days prior to the theophylline infusion. During enoxacin coadministration, elimination half-lives of theophylline increased from 8.7 to 17.4 hours and from 6.1 to 12.3 hours, respectively. Total body clearance of theophylline decreased in both volunteers, whereas renal clearance did not alter. From this it was concluded that the decreased elimination results from a reduced metabolic clearance. During enoxacin coadministration, the formation of the metabolites 1-methyluric acid and 3-methylxanthine clearly was decreased, whereas the formation of 1,3-dimethyluric acid was less affected compared with the blank period. Interference with theophylline disposition by enoxacin is based predominantly on inhibition of microsomal N-demethylation. Ofloxacin comedication did not cause a change in the plasma parameters or renal excretion of theophylline and its metabolites compared with the blank period.

The bioavailability of a new ambroxol sustained release preparation (75 mg) based on a dialyzing membrane for controlled release was studied in healthy volunteers after single and multiple oral dose in comparison with a standard sustained release formulation in a cross-over study under carefully controlled conditions. Plasma concentrations of ambroxol were measured by means of a HPLC method. Based on AUC data both preparations are found to be bioequivalent, but show different plasma concentration profiles. The test preparation showed a more pronounced sustained release profile than the reference preparation (single dose) resulting in significantly higher steady state plasma levels.

The use of durable medical equipment in the home, while not a recent development, was formally recognized by the Congress with the passage of the original Medicare legislation. Since that time the statute has been amended to provide for a more workable, economical, and desirable interface among the administrative, supplier, and user communities. To assist in achieving this end, a research project was begun in October 1976 that has yielded data on Federal expenditures for reimbursement of rental and purchase costs of this equipment. Data were extracted from the Beneficiary History Files of five Part B carrier in 11 geographic areas covering the period 1976-1977. These data included the type of equipment; rental or purchase decision; submitted charges; allowed charges, and reimbursement by Medicare. Some 1.3 million individual records, from approximately 400,000 beneficiaries, were tabulated and analyzed. The exploratory nature of this research has provided a benchmark for future research and policy considerations. This article details various characteristics of the data collected for the project.

Sulfadiazine, sulfamerazine, sulfadimidine and their corresponding N4-acetyl derivatives were administered to man. The percentages of acetylation and deacetylation, protein binding, half-lives of elimination and apparent and true renal clearance values were measured. Methyl substitution in the N1-pyrimidine ring favours acetylation by an additional N-acetyltransferase isoenzyme present in 'fast' acetylators only. Methyl substitution in the N1-pyrimidine ring favours renal clearance of the N4-acetylsulfonamide derivatives. The N1-substituent probably reinforces the binding of the N4-acetyl group to the active tubular transport mechanism. The renal clearance of these sulfonamides is not dependent on the structure of the N1-substituent.

After a rectal dose of 500 mg in a suppository, naproxen is 6-O-demethylated (20%) and glucuronidated (40%), the metabolites are subsequently excreted renally. The elimination half-life is 15.2 +/- 2.6 h. Ten out of 22 subjects show biphasic elimination kinetics with half-lives of 7 and 15 h, respectively. There is a wide range in the percentage of the dose that is glucuronidated and demethylated (20-70%). This variation does not deviate from a normal distribution.

The pharmacokinetic parameters of theophylline and its major metabolites were measured in two healthy volunteers, after the administration of theophylline alone and during co-medication with ofloxacin, 200 mg twice daily, or enoxacin, 200 mg twice daily. During enoxacin co-medication, elimination half-lives of theophylline increased from 8.7 h to 17.4 h and from 6.1 to 12.3 h, respectively. As the renal clearance of theophylline did not change, the decreased elimination of theophylline during enoxacin co-medication must result from a reduced metabolic clearance. Enoxacin co-medication caused a clearly decreased formation of the metabolites 1-methyluric acid and 3-methylxanthine, formed by N-demethylation, whereas the C-8 oxidation of theophylline was less influenced compared to the blank. Enoxacin's interference with the theophylline disposition is predominantly based on the inhibition of the microsomal N-demethylation. Ofloxacin co-medication did not induce a change in the plasma parameters or renal excretion of theophylline and its metabolites.

The pharmacokinetic parameters of 16 patients in the intensive care unit, sedated with midazolam, were evaluated. A large variation was observed in the plasma concentration of midazolam and between the plasma concentration of midazolam and its metabolite 1-hydroxymethylmidazolam glucuronide. The plasma albumin concentration governs the volume of distribution of midazolam. Decreased plasma albumin concentration (25 gm/L) results in an increased volume of distribution and a decreased elimination rate of midazolam. The observed plasma concentration ratio between the parent drug and its metabolite 1-hydroxymethylmidazolam glucuronide is governed by the variables of protein binding, the metabolic rate of midazolam, and the renal clearance of the glucuronide metabolite itself (which can be considered as a measure of the kidney function of the patient).

In five cases of carbamazepine (CBZ) intoxication, the time curves of the plasma concentration and of the renal excretion rate of carbamazepine and its metabolites carbamazepine 10,11-epoxide (CBZ-epoxide) and trans-10,11-dihydro-10,11-dihydroxy-CBZ (CBZ-diol) were measured. Pseudo-steady-state or plateau-like plasma concentration-time curves were observed when doses of 12 or 18 g of CBZ were ingested. Hemoperfusion lowers the plasma concentration of CBZ and its metabolites by affecting the half-life. The effect of hemoperfusion is reduced by the continuous absorption from the gastrointestinal tract and redistribution from the tissues. The renal clearances of CBZ and of CBZ-epoxide are low (1 and 8 ml/min, respectively); both are flow dependent. The renal clearance of CBZ-diol is approximately 160-350 ml/min and is independent of the urine flow. Although urine stimulation increases the renal clearance of CBZ by 100%, the overall amount excreted increases only 1-2% of the dose. Protein binding of CBZ is approximately 80%, of CBZ-epoxide 50%, and of CBZ-diol 70%.