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Multiple unconventional superconducting phases are suspected to be driven by magnetic fluctuations in the heavy-fermion paramagnet UTe$_2$, and a challenge is to identify the signatures of the electronic correlations, including the magnetic fluctuations, in the bulk physical quantities. Here, we investigate thoroughly the anisotropy of the electrical resistivity of UTe$_2$ under intense magnetic fields up to 70~T, for different electrical-current and magnetic-field configurations. Two characteristic temperatures and an anisotropic low-temperature Fermi-liquid-like coefficient $A$, controlled by the electronic correlations, are extracted. Their critical behavior near the metamagnetic transition induced at $\mu_0H_m\simeq35$~T for $\mathbf{H}\parallel\mathbf{b}$ is characterized. Anisotropic scattering processes are evidenced and magnetic fluctuations are proposed to contribute, via a Kondo hybridization, to the electrical resistivity. Our work appeals for a microscopic modeling of the anisotropic contributions to the electrical resistivity as a milestone for understanding magnetically-mediated superconductivity in UTe$_2$., Comment: - Main text: 10 pages, 5 Figures and 60 References - Supplemental Material: 5 pages, 5 Figures, 1 Table and 11 References - there was a problem with Refs. in version 1 of the preprint, this is corrected in version 2 of the preprint

Superconductivity induced by a magnetic field near metamagnetism is a striking manifestation of magnetically-mediated superconducting pairing. After being observed in itinerant ferromagnets, this phenomenon was recently reported in the orthorhombic paramagnet UTe$_2$. Under a magnetic field applied along the hard magnetization axis b, superconductivity is reinforced on approaching metamagnetism at $\mu_0H_m$ = 35 T, but it abruptly disappears beyond $H_m$. On the contrary, field-induced superconductivity was reported beyond $\mu_0H_m$ = 40-50 T in a magnetic field tilted by $\simeq25-30\deg$ from b in the (b,c) plane. Here we explore the phase diagram of UTe2 under these two magnetic-field directions. Zero-resistance measurements permit to confirm unambiguously that superconductivity is established beyond Hm in the tilted-field direction. While superconductivity is locked exactly at fields either smaller (for a H || b), or larger (for H tilted by $\simeq27\deg$ from b to c), than Hm, the variations of the Fermi-liquid coefficient in the electrical resistivity and of the residual resistivity are surprisingly similar for the two field directions. The resemblance of the normal states for the two field directions puts constraints for theoretical models of superconductivity and implies that some subtle ingredients must be in play., Comment: 18 pages, 5 Figures, includes Supplementary Information (9 pages, 8 Figures)

The discovery of superconductivity in the heavy-fermion paramagnet UTe$_2$ has attracted a lot of attention, particularly due to the reinforcement of superconductivity near pressure- and magnetic-field-induced magnetic quantum phase transitions. A challenge is now to characterize the effects of combined pressure and magnetic fields applied along variable directions in this strongly anisotropic paramagnet. Here, we present an investigation of the electrical resistivity of UTe$_2$ under pressure up to 3~GPa and pulsed magnetic fields up to 58~T along the hard magnetic crystallographic directions $\mathbf{b}$ and $\mathbf{c}$. We construct three-dimensional phase diagrams and show that, near the critical pressure, a field-enhancement of superconductivity coincides with a boost of the effective mass related to the collapse of metamagnetic and critical fields at the boundaries of the correlated paramagnetic regime and magnetically-ordered phase, respectively. Beyond the critical pressure, field-induced transitions precede the destruction of the magnetically-ordered phase, suggesting an antiferromagnetic nature. By bringing new elements about the interplay between magnetism and superconductivity, our work appeals for microscopic theories describing the anisotropic properties of UTe$_2$ under pressure and magnetic field., 12 pages, 7 figures

Purpose: This study identifies factors associated with care engagement along the cancer survivorship care continuum for Floridians. Methods: We identified patients from the OneFlorida Data Trust with a cancer diagnosis at any age and encounters from 2012-2020. Multivariable logistic regression models produced odds ratios (OR) predicting 1) any outpatient non-acute care visit, 2) cancer-related visit with any provider, 3) cancer-related visit with a cancer provider, and 4) survivorship visit with a cancer provider. Encounter-based independent variables were insurance, Social Deprivation Index quartile, and Rural Urban Continuum Area (adjusted for age, sex, race, ethnicity, and treatment). Results: 662,489 survivors were included in the sample. Those with Medicaid and dual eligible status (Medicare and Medicaid) were more likely to have an outpatient visit (Medicaid OR 2.02, 95%CI 1.93-2.12; dual eligible 3.06, 2.91-3.22) or a cancer-related visit with a cancer provider (Medicaid 1.82, 1.77-1.86; dual eligible 1.32, 1.28-1.35), and less likely to have a survivorship visit (Medicaid 0.27, 0.26-0.28; dual eligible 0.20, 0.19-0.21). Uninsured survivors were less likely to have all visit types, while those with Medicare were more likely. Those from the most socially deprived areas were more likely to have an outpatient visit (1.09, 1.03-1.14) and less likely to have a cancer-related visit with any provider (0.90, 0.88-0.92) or a cancer provider (0.93, 0.91-0.95). Survivors from non-metropolitan areas were more likely to have an outpatient visit (1.38, 1.22-1.56), cancer-related visit (1.22, 1.16-1.28), cancer-related visit with a cancer provider (1.45, 1.39-1.52), and a survivorship visit (1.34, 1.22-1.48). Conclusions: Survivors who have public insurance are more likely to have outpatient visits, and those with Medicaid or dual eligible status are less likely to have survivorship visits. Uninsured status is consistently associated with lack of engagement across the care continuum. Those from areas with higher social deprivation are more likely to have outpatient visits, but less likely to have a cancer-related visit with or without a cancer provider. Survivors from non-metropolitan areas are more likely to engage in all visit types along the care continuum.

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The Closure Fast™ Endovenous Radiofrequency Ablation Catheter is the latest version of a minimally invasive system for the treatment of patients with superficial venous disease. The Closure Fast™ catheter heats the vein wall to 120°C, causing denaturation of the collagen of the vein wall and contraction of the vessel such that no blood can flow through it. Nearly one million systems have been sold since the product was launched. Many, if not all, patients can be treated under local anesthesia with the Closure Fast™ catheter. Duplex ultrasound reports occlusion rates for the treated vein of 94%–98% at 1 year and 85%–93% at 3 years. The system produces average postoperative pain scores of less than 2 out of 10 on a visual analog score. In the first postoperative week, 76% of patients do not require analgesia. Some 45% of patients return to normal activity on the first postoperative day. Serious complications appear to be rare following the Closure Fast™ procedure. Transient paresthesia occurs in 0.2% of cases, thrombophlebitis in 1%–10%, and thromboembolic events in up to 1.4%, mainly heat-induced thrombosis. Closure Fast™ adds significant costs to treating superficial venous disease but studies have shown it to be cost-effective when used in an office setting.

We have insufficient resources to give every patient the treatments that they and their surgeons might wish for. The problem is not unique to ophthalmology.1 National Institute for Health and Care Excellent guidance is just that, …

ObjectivesTo determine the feasibility and reliability of an online patient completed Aberdeen Varicose Vein Questionnaire (AVVQ) as a tool to guide specialist referral.MethodsThis was a prospective qualitative and quantitative study. One hundred and six patients completed an online questionnaire. Some 43 (40%) completed the AVVQ questionnaire at home and 63 (60%) did it immediately before their appointment.Venous Clinical Severity Score (VCSS) and CEAP grades were assigned by a consultant vascular surgeon. In 11 patients, the questionnaire was repeated at the time of surgery to assess reproducibility and bias.ResultsThe AVVQ correlated with the specialist's VCSS scores (Spearman coefficient 0.795; p

Pressure is the cleanest way to tune heavy fermion systems to a quantum phase transition in order to study the rich physics and competing phases, and the comparison between ytterbium and cerium systems is particularly fruitful. We briefly review the mechanisms in play and show some examples of expected and unexpected behaviour. We emphasize the importance of the valence changes under pressure and show how modern synchrotron techniques can accurately determine this, including at low temperature., Comment: To appear in proceedings of International Conference on Superconductivity and Magnetism ICSM 2012 (Istanbul)

Here we review measurements of the normal and superconducting state properties of iron-based superconductors using high magnetic fields. We discuss the various physical mechanisms that limit superconductivity in high fields, and the information on the superconducting state that can be extracted from the upper critical field, but also how thermal fluctuations affect its determination by resistivity and specific heat measurements. We also discuss measurements of the normal state electronic structure focusing on measurement of quantum oscillations, particularly the de Haas-van Alphen effect. These results have determined very accurately, the topology of the Fermi surface and the quasi-particle masses in a number of different iron-based superconductors, from the 1111, 122 and 111 families. © 2012 Académie des sciences.

To evaluate early patency rate of the heparin-bonded stent grafts in atherosclerotic long femoropopliteal occlusive disease, and to identify factors that affect outcome.Heparin-bonded Viabahn stent grafts were placed in 33 limbs in 33 patients during 2009-2010. The stents were deployed to rescue failed conventional balloon angioplasty. Mean age was 69 (range 44-88) years, and 67 % (22 of 33) were men. Most procedures (21 of 33, 64 %) were performed for critical limb ischemia (33 % for rest pain, 30 % tissue loss). Kaplan-Meier plots and Cox regression analysis were used to identify significant risk factors.The average length of lesions treated was 25 ± 10 cm, and they were predominantly TASC (Transatlantic Intersociety Consensus) D (n = 13) and C (n = 17) lesions. The median primary patency was 5.0 months (95 % confidence interval 1.22-8.77). The mean secondary patency was 8.6 months (95 % confidence interval 6.82-10.42). Subsequently, 4 patients underwent bypass surgery and 5 patients underwent major amputation. One patient died. There were 5 in-stent or edge-stent stenoses. Cox multivariate regression analysis identified TASC D lesions to be a significant risk factor for early occlusion (p = 0.035).TASC D lesions of femoropopliteal occlusions have poor patency rates with the use of heparin-bonded stent grafts after failed conventional angioplasty. Alternative options should be considered for these patients.

The Hardman index is a predictor of 30-day mortality after open ruptured abdominal aneurysm repair through the use of preoperative patient factors. The aim of this study was to assess the Hardman index in patients undergoing endovascular repair of ruptured aortic aneurysms.A retrospective analysis of 95 patients undergoing emergency endovascular repairs of computed tomography-confirmed ruptured aneurysms from 1994 to 2008 in a university hospital was performed. All relevant patient variables, calculations of the Hardman index, and the incidence of 30-day mortality were collected in these patients. Correlation of the relationship between each variable and the overall score with the incidence of 30-day mortality was undertaken.The 24-hour mortality was 16% and 30-day mortality 36%. Increasing scores on the Hardman index showed an increasing mortality rate. Thirty-day mortality in patients with a score of 0 to 2 was 30.5%, and in those with a score of ≥3 was 69.2% (P = .01, risk ratio = 2.26, 95% confidence interval = 0.98 to 5.17). This is lower than predicted in both patient groups based on Hardman index score. Loss of consciousness was the only statistically significant independent predictor of 30-day mortality with a risk ratio of 3.16 (95% confidence interval = 2.00-4.97, P.001).These data suggest that the Hardman index can predict an increased risk of 30-day mortality from endovascular repairs of ruptured aortic aneurysms. However, mortality from endovascular repair is much lower than would be predicted in open repair and it therefore cannot be used clinically as a tool for exclusion from intervention.

Purpose: To review the outcomes of patients undergoing emergency endovascular repair of aortocaval fistula (ACF) secondary to abdominal aortic aneurysm (AAA). Case Report: Four consecutive patients who underwent emergency endovascular repair of ACF associated with AAA in a tertiary institution between 2002 and 2009. Of the 4 patients, 3 had initially been misdiagnosed and managed for several days by other specialists for their symptoms prior to diagnosis of their ACF. Three patients died in the early postoperative period. The fourth patient made a satisfactory postoperative recovery but subsequently required further endovascular surgery to treat a persistent type 1 endoleak. Conclusions: Our experience illustrates the importance of early diagnosis and management of ACF. Even in experienced hands, the management of spontaneous ACF associated with AAA is challenging. Endovascular surgery may still have a role in improving outcomes in these patients.

We investigated the psychology of risk in the context of residential property investment. One hundred and thirty‐seven participants completed a questionnaire that measured their sensation‐seeking, general investment risk attitude, and attitude and confidence about investing in a term deposit, unit trust shares, a residential property syndicate and residential property. People with higher sensation seeking scores found shares and unit trusts more attractive than low sensation seekers, but all groups were most confident about investing in residential property. Overall the results indicate that New Zealanders invest overwhelmingly in real estate because they trust it more than other forms of investment.

Recent studies have suggested that endovascular aneurysm repair (EVAR) may reduce the perioperative mortality of ruptured abdominal aortic aneurysm (AAA). Whether EVAR confers any long-term survival advantage over published results for open repair of ruptured AAA has not been established. We conducted a single-center retrospective study over a 10-year period (1994–2004) examining the long-term outcome of patients who have undergone endovascular repair of ruptured AAA. Fifty-four patients underwent endovascular repair of a ruptured AAA. The median age was 75 years (interquartile range 69.5–79.5 years); 42 (78%) patients were male. The perioperative mortality rate was 37%. During a median follow-up of 32 months (range 14–48 months), there were 5 aneurysm-related and 13 non-aneurysm-related deaths. Overall, the 3- and 5-year survival rates were 36% and 26%, respectively. EVAR does not appear to confer any overall survival advantage in the mid- to long term compared with the published results for open repair. The reasons for this remain unclear. Further, larger studies are required to confirm these results.

Objectives Inadvertent intra-arterial injection is a rare and serious complication of sclerotherapy. Multiple treatments have been used in reported cases, with varying levels of success. We report a rare case of intra-arterial injection being treated with steroids and pulsed dye laser therapy and present a plan for future incidences. Method/Case A 52-year-old woman presented to the clinic looking for aesthetic improvement to telangiectatic veins on the anterior aspect of the right leg. She developed cutaneous necrosis after sclerotherapy injection with 4 mL of 0.5% liquid polidocanol. Results After 23 months of pulsed dye laser therapy and a course of oral prednisolone, the patient made a good recovery and is left with minimal lasting tissue damage. Conclusions More research is needed into the area of treating cutaneous necrosis with a pulsed dye laser, but this case report indicates a possible future therapeutic use after a successful outcome.

Purpose: To determine in a retrospective analysis the incidence of renal impairment (RI) following endovascular repair (EVR) of abdominal aortic aneurysm (AAA), to assess the morbidity and mortality in endograft patients with preoperative RI, and to examine the impact of suprarenal stent-grafts on renal function. Methods: From March 1994 to October 2001, 315 AAA patients (289 men; mean age 72.4±7.0 years) undergoing EVR were entered prospectively into a vascular registry. The patients received either an in-house custom-made stent-graft or one of several commercially made devices implanted with infrarenal or suprarenal fixation. Renal function was monitored by serum creatinine measurements prior to discharge and at 3, 6, and 12 months and annually thereafter. Preoperative RI was defined as a serum creatinine > 130 μmol/L and/or long-term dialysis. Postoperative RI referred to a >20% increase in the serum creatinine over baseline. Additional deterioration of renal function in patients with preoperative RI was referred to as postoperatively worsened RI. Results: Of the 315 patients treated, 220 (69.8%) were considered high risk (ruptured AAA or ASA grade III or IV). Sixty-nine (21.9%) patients had preoperative RI (6 [1.9%] on preoperative dialysis). A suprarenal stent-graft was used in 169 (53.7%) patients and infrarenal stent-graft in the remaining 146 (46.3%). The mean follow-up was 30.1 ±22.7 months. Postoperative RI occurred in 53 (16.8%) patients (24 [7.6%] transient, 29 [9.2%] persistent). Patients with preoperative RI had a significantly higher incidence of postoperatively worsened RI (37.7% versus 11.0%, pConclusions: Endovascular AAA repair may lead to persistent postoperative RI in nearly 10% of cases, especially in patients with preoperative RI. Suprarenal stent-graft fixation does not seem to have any deleterious effect on renal function. Further long-term studies are required to confirm the innocuous nature of transrenal stent placement.

Endovascular aneurysm repair (EVAR) is a controversial technique, which remains the subject of a number of prospective randomised trials. Although questions remain regarding its long-term durability objective evidence exists which demonstrates its reduced physiological impact compared with conventional open repair. If this technique could be used in patients with ruptured abdominal aortic aneurysm (AAA) it may reduce the high peri-operative mortality. A review of the literature identified a limited experience with EVAR of ruptured AAA. Only a small number of case series with selected patients exist. The majority of patients were haemodynamically stable. However, the selective use of aortic occlusion balloons allowed successful endovascular management in a small number of unstable cases. All investigators had access to an “off the shelf” endovascular stent-graft (EVG). Per-operative mortality ranged from 9 to 45% and may reflect increasing experience and patient selection. A number of patients who underwent successful EVAR were turned down for open repair. A number of important lessons have been learned from these studies but questions remain regarding patient suitability and staffing issues. If these difficulties can be surmounted then the technique may offer an alternative to open repair. Eur J Vasc Endovasc Surg 25, 191–201 (2003)

Background measurement of ankle brachial pressure indices (ABPI) is important in the assessment of patients with peripheral vascular disease. Methods thirty-one hospitals with a vascular surgeon were selected at random. A telephone questionnaire was completed to assess the method used for the measurement of ABPI. Following the survey, 14 patients with peripheral vascular disease had their ABPI measurement done by two observers, a pre-registration house officer and a clinical nurse practitioner. Observers were blinded to their own and each other's results. Brachial systolic pressures were obtained using a DINAMAPTM(Critikon, Tampa, U.S.A.) automated blood pressure monitor, the Korotkoff method (12 cm cuff, parallel wrap) and an 8 MHz Doppler probe (Huntleigh) and sphygmomanometer. Ankle systolic pressures were obtained using the Doppler probe. The results were analysed using the Wilcoxon signed rank test. Results the survey demonstrated that at the majority of centres with vascular laboratories the brachial artery systolic pressures were measured using a Doppler probe. In contrast, at centres where the house officers performed the routine measurements, over 60% used the Korotkoff method to obtain this reading. One in four nurse practitioners used the Korotkoff method. When the ABPI values were calculated, the DINAMAP produced significantly higher median values than the Korotkoff (0.79 vs 0.72, p=0.003) and Doppler methods (0.79 vs 0.70, p

Background The aim of this study was to determine the outcome of patients who presented with sudden onset of incapacitating claudication of less than 2 weeks' duration and who were treated with peripheral arterial thrombolysis. Methods The database of the Thrombolysis Study Group was searched retrospectively for patients who received thrombolysis for acute-onset claudication. Some 108 patients (65 men, median age 69 (range 29–94) years) were treated with intra-arterial tissue plasminogen activator at 14 hospitals. The median duration of symptoms was 72 h (range from 2 h to 2 weeks). There were 52 graft and 56 native vessel arterial occlusions. Results The immediate outcome of thrombolysis for native vessel arterial occlusion was thrombus clearance in 50 patients (89 per cent) and failed lysis in six (11 per cent). Thirty-six patients (64 per cent) had a secondary radiological or surgical procedure carried out after lysis. After 30 days four patients (7 per cent) had a major amputation, eight (14 per cent) had died, 38 (68 per cent) were symptom free and seven (12 per cent) continued to have claudication. Three patients (5 per cent) suffered a major haemorrhage. The immediate outcome of thrombolysis for graft occlusion was thrombus clearance in 48 patients (92 per cent) and failed lysis in four (8 per cent); 27 patients (52 per cent) had a secondary procedure. After 30 days four patients (8 per cent) had a major amputation, seven (13 per cent) had died, 32 (62 per cent) were symptom free and nine (17 per cent) had persistent claudication. Three patients (6 per cent) suffered a major haemorrhage. Conclusion Patients who presented with acute onset of incapacitating claudication had an outcome similar to that after thrombolysis for critical ischaemia. It is recommended that patients who present in this way should be observed and treated with thrombolysis only if they progress to critical ischaemia.

Objective: Endovascular repair (EVR) of abdominal aortic aneurysm (AAA) has many potential advantages, one of which may be reduced blood product requirements. The aim of this study was to compare the current blood product usage in our unit for three types of elective operation: EVR of AAA, open AAA repair and femorofemoral crossover grafts. Design: Prospective data analysis with historical controls. Materials: One-hundred and thirty-two patients undergoing elective EVR of AAA, 35 patients undergoing elective open repair of AAA and 37 patients having femorofemoral crossover grafts. Methods: Data was collected on the blood product requirements of patients having EVR of AAA, with open AAA repair and femorofemoral crossover graft providing historical controls. Results: There was no difference in the haematological parameters preoperatively between the three groups but postoperatively patients having EVR had a slightly lower haemoglobin than the open group (10.6 g/dl vs. 10.85 g/dl, p = 0.015). The number of patients who received blood transfusion in the EVR group was 82/132 (62%) and the open group 27/35 (77%), p = 0.4. Conclusion: Patients undergoing EVR of AAA require blood transfusion in the same numbers when compared to those undergoing open repair.

Background The aim of this study was to determine whether the routine use of an antibiotic-bonded gelatin-coated Dacron graft could reduce the incidence of prosthetic graft infection. Extra-anatomic grafts were chosen for study as they have the highest risk of graft infection. This paper reports early results up to 1 month after surgery. Methods This multicentre study involved 14 vascular units in the UK. A total of 257 patients underwent extra-anatomic bypass. Patients were randomized to rifampicin bonding (1 mg/ml rifampicin soak for 15 min before graft insertion) or a control group. Routine three-dose antibiotic prophylaxis was administered to patients in both groups. Results There were 178 men and 79 women of median age 69 (range 43–92) years. Rifampicin-bonded (n=123) and control (n=134) groups were well matched for clinical details, risk factors and operative techniques. No side-effects were noted from rifampicin bonding. Only one patient (in the control group) developed a graft infection and this proved fatal. There were no significant differences between bonded and unbonded grafts in terms of perioperative mortality rate (9 and 5 per cent respectively), median hospital stay (10 days for both groups), total infective complications (15 and 21 per cent respectively) or need for postoperative antibiotics (13 and 18 per cent respectively). Conclusion Early results from this study have not identified any significant advantage in the routine use of rifampicin bonding, but the rate of graft infection was very low (0·4 per cent). Gelatin coating alone may provide protection against infection. Definitive recommendations about the role of antibiotic bonding cannot be made until longer follow-up becomes available.

Transport measurements on a single crystal of the heavy fermion superconductor CeCu2Si2 have been performed under pressure in a diamond anvil cell with helium as pressure transmitting medium. Probably because of the very hydrostatic conditions, the superconducting transition is shown to remain narrow under pressure. The temperature dependence of the upper critical field, Hc2, is analyzed assuming strong coupling. The effective mass is found to decrease consistently with other reports, but the expected sharp increase of Tc under pressure is not found in the sample here.

The magnetic properties of the cubic NaCl uranium and neptunium monopnictides (UX, NpX; X=N, P, As, Sb, Bi) have been widely studied at ambient pressure. Properties ranging from itinerant to localized magnetism, and a variety of ordered magnetic structures have been observed. In particular the profusion of non-collinear double- k or triple- k structures is a consequence of strongly anisotropic exchange interactions. The application of pressure is a clean way of continuously varying the lattice parameter, and the exchange interactions, from one compound to another. A number of studies have been performed using different high pressure techniques. Some of the effects of pressure can be understood in a simple picture of a continuous variation of the lattice parameter, but some highly anomalous effects are also found which are discussed in relation to the possible nature of the magnetic interactions.

We have developed a SQUID picovoltmeter and precise temperature control ( ∼μK) to measure sharp R(T) superconducting transitions of low impedance samples, with low current densities. We present measurements obtained on a bulk cylinder of lead (Φ0.25 mm) in transverse magnetic field. A distinctive hysteretic step structure is observed. It is washed out on increasing the current, and reinforced in higher field. Classical models for the dissipation mechanisms in the intermediate state are briefly reviewed and used to give a first interpretation of these results, although a complete understanding is not reached yet.

We report on high-pressure studies performed on the neptunium pnictides NpAs and NpBi via electrical resistance up to $\ensuremath{\sim}25\mathrm{GPa}$ between 1.3 K and room temperature, and on a high-pressure investigation up to 9 GPa and at 4.2 K on NpSb using ${}^{237}\mathrm{Np}$ M\"ossbauer spectroscopy. This work extends previous high-pressure studies carried out on NpAs via M\"ossbauer spectroscopy, on NpSb via resistance, and on all pnictides via x-ray study. In $\mathrm{Np}X$ $(X=\mathrm{A}\mathrm{s},\mathrm{S}\mathrm{b},\mathrm{B}\mathrm{i})$ crystallizing in the cubic-NaCl phase the ground state is antiferromagnetic and displays a noncollinear 3k spin structure. The strong increase of the resistivity with decreasing temperature observed in the temperature range of the 3k order at ambient pressure collapses at 0.23 (NpAs), 2.7 (NpSb), and 3.9 GPa (NpBi). No significant change of the hyperfine interactions is found in NpAs or NpSb at the pressure where the resistance collapse is observed. The Kondo anomaly of the resistivity observed at ambient pressure disappears above 25 GPa (NpAs), 2.7 GPa (NpSb), and 3 GPa (NpBi). The N\'eel temperature ${T}_{N}$ of all compounds and the ordered moment of NpAs and NpSb decrease with reduced volume. For NpAs and NpBi the resistance indicates the presence of magnetic order at least up to 16 GPa. The compounds undergo a pressure-induced structural transition with a volume reduction by $\ensuremath{\sim}10%.$ Although in the resistance of NpSb the signature of magnetic order is lost already at 8 GPa in the high-pressure phase, a magnetic hyperfine field is present, which is reduced by $\ensuremath{\sim}30%$ relative to the NaCl phase. It is suggested that the resistance collapse is caused by a change of the magnetic structure, that the decrease of ${T}_{N}$ is due to a modification of the Fermi surface besides a small $5f$ delocalization, and that in NpSb the volume reduction in the structural high-pressure phase leads to an enhanced $5f$ delocalization.

Introduction Accelerated thrombolysis with high-dose bolus tissue plasminogen activator (tPA) may enable patients with more severe acute leg ischaemia to be treated without recourse to surgery. This study was a randomized comparison of two thrombolytic regimens. Methods One hundred patients with acute leg ischaemia of less than 30 days' duration were randomized to receive either high-dose bolus tPA (three doses of 5 mg over 30 min, then 3.5 mg/h for up to 4 h, then 05-1.0 mg/h) or conventional low-dose tPA (0.5-1.0 mg/h). The groups were well matched for age, cardiovascular risk factors, duration and severity of ischaemia, site, cause and length of arterial occlusion. Results The median duration of infusion in the high-dose group was 40 (range 0.25-46) h compared with 21 (range 2-46) h for low-dose infusion (P < 0.0001). Successful thrombolysis was achieved in 45 of 49 high-dose and 39 of 44 low-dose infusions but significantly more adjunctive procedures were required following high-dose bolus infusion (26 versus 16 patients) (P = tJ002). Thirty days aftcr treatment was commenced, limb salvage was achieved in 39 of 49 patients in the high-dose group compared with 37 of 44 who had a low-dose infusion of tPA. Six and two patients respectively required amputation. Four patients in the high-dose group and five in the low-dose group died. Three patients in each group suffered a major haemorrhage and one in the low-dose group had a stroke. Conclusion High-dose bolus therapy significantly accelerated thrombolysis with tPA without compromising outcome. Some 50 per cent of patients were treated within 4 h enabling thrombolysis to be used as primary therapy for patients with acute critical ischaemia.

Background Acute leg ischaemia is both life threatening and limb threatening. This audit was designed to determine the incidence and outcome of acute leg ischaemia in a single county. Methods Using multisource data collection for a 1-year interval in 1994 all patients with acute leg ischaemia were identified prospectively using hospital and general practice records in the county of Gloucestershire, population 540 000. Results Seventy-seven patients with 84 events of acute leg ischaemia were identified, giving an incidence of one per 7000 per year rising to one per 6000 per year when bypass graft occlusions were included. All but four patients were treated in hospital. Sixteen of 80 hospital events involved conservative treatment; after 30 days nine patients had died and two required amputation. The remaining five patients had borderline ischaemic rest pain and accepted their symptoms without intervention. Sixty-four of 80 events were managed by either primary surgery and angioplasty (n = 31) or thrombolysis (n = 33). The 30-day outcome in patients treated actively was: limb salvage in 50 (78 per cent), amputation in four (6 per cent) and death in ten (16 per cent). Conclusion In Gloucestershire almost all cases of acute leg ischaemia are managed by, or discussed with vascular surgeons. A flexible integrated policy of surgery and peripheral thrombolysis has resulted in a limb salvage rate of 78 per cent in patients suitable for active treatment.

WHAT THIS PAPER ADDSThis single-centre retrospective study demonstrates that young patients with abdominal aortic aneurysms havesignificant comorbidities and do not necessarily have a long life expectancy. It would be therefore reasonable tooffer endovascular repair to this subgroup of patients.Objectives: To compare the mid-term outcome and secondary intervention rate following elective open andendovascular aortic aneurysm repair (EVAR) in patients aged 65 years and younger.Methods: A retrospective analysis of patients aged 65 years and younger who had elective abdominal aorticaneurysm repair (AAA) between 1994 and 2012.Results: One hundred and sixty-five patients under the age of 65 years (mean age: 61 years 4; 8 women) hadelective abdominal aneurysm repair (97 EVAR and 68 open). The overall 30-day mortality rate was 3.7% (2.1%EVAR and 5.9% open). Forty per cent of patients had died at a median follow up of 77 months (interquartilerange, 36e140). Most deaths were not related to aneurysm.There was no difference in the long-term mortalitybetween the EVAR and open groups (hazard ratio [HR] ¼ 1.22; 95% confidence interval [CI] 0.75e1.98, p ¼ .43),but there was a trend of better outcomes with the use of commercially made endografts over open repair(HR ¼ 2.9; 95% CI 0.9e10.0, p ¼ .08) and custom-made endografts (HR ¼ 3.1, 95% CI 0.9e10.3;p ¼ .07). Elevenper cent of patients who had EVAR required a further procedure compared with 13% who had open repair. Allbut one of the re-interventions in the EVAR group was performed on patients who had custom-madeendografts.Conclusions: Young patients with AAA have significant comorbidities and do not necessarily have long lifespans.In the less fit younger patients with AAA, the results with EVAR are comparable with fit patients who had openAAA repair.The management of fitter young patients with AAA remains controversial, but improving results withEVAR over time may increase the role of EVAR in this group. 2013 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.Article history: Received 21 December 2012, Accepted 22 April 2013, Available online XXXKeywords: Abdominal aortic aneurysm, Endovascular aortic aneurysm repair, OutcomesINTRODUCTIONRandomised studies have demonstrated benefit fromendovascular aneurysm repair (EVAR) when compared withopen repair of abdominal aortic aneurysms (AAAs).

Central venous catheterization is a common procedure performed in the critically ill patient. The complication associated with this invasive procedure is well established. However, complication related to the guide wire is rare. We present a case of knotted and entrapped guide wire following central venous catheterization using the Seldinger method and technique to retrieve it nonoperatively.

The cost of attempting limb salvage in patients who presented with acute lower limb ischaemia was recorded prospectively for 20 months. Seventy-five patients were admitted during the study; 45 were treated primarily by radiological intervention and 18 had primary surgery. The remainder were treated conservatively. Patients who had primary surgery required fewer visits to the operating theatre than those who had primary thrombolysis, but there was no difference in the total time that the theatre or radiology suite was occupied: median 2·3 (10th centile range 1·5–5·0) h and 3·0 (2·0–5·0) h respectively. Median (range) cost of disposables for performing surgery was £82 (58–169) and for thrombolysis was £407 (252–596). When the costs of using the theatre or radiology suite were included, the costs of both treatments were similar: surgery £683 (309–1438) and lysis £861 (611–1244). Median (10th centile range) inpatient stay for surgical patients was 9 (3–18) days and for those having thrombolysis 11 (2–29) days. Median (10th centile range) costs for bed occupancy were similar in both groups: surgery £2497 (643–9115) and lysis £2189 (902–6020). Mean cost for attempting limb salvage by surgery was £3429 (1094–10 065) compared with £3230 (1543–8353) for thrombolysis.

High-pressure resistance and neutron scattering measurements have been performed on single crystals of USb. It is shown that the effect of pressure is to reduce the ordering temperature of the antiferromagnetic triple-k phase at a rate of -17 K/GPa. This phase exists at least up to 6 GPa. However, above 2 GPa, a second magnetic phase transition occurs at low temperature, below about 80 K. From the neutron data, the new phase is found to have the same wave vector, k = (1,0,0), as the triple-k structure, but a careful analysis of domain population effects suggests that it is most likely single-k. The appearance of a single-k structure at low temperature, while a multi-k structure is stable at a higher temperature, is at variance with the behaviour normally encountered in this type of systems. However, it is shown to fit into a unified phase diagram of the uranium monopnictides.

OBJECTIVE: The study objective was to evaluate the feasibility of laparoscopic aortofemoral bypass in a porcine model. SUMMARY BACKGROUND DATA: Laparoscopic techniques have been applied to numerous general and thoracic surgical procedures. Their application to vascular surgery has been virtually nonexistent. Open surgery for aortoiliac occlusive disease is accompanied by significant morbidity rates, and minimally invasive procedures have the disadvantage of reduced patency rates. Laparoscopic aortofemoral replacement has the theoretical advantage of long-term patency with reduced postoperative complications. METHODS: Between January and September 1993, laparoscopic surgery was performed on 16 pigs: 6 underwent transperitoneal laparoscopic aortic dissection and vessel control alone; 7 underwent complete transperitoneal laparoscopic aortofemoral bypass; and 3 underwent a retroperitoneal approach. The aortic anastomosis was performed using a combination of sutures and titanium clips in an end-to-side fashion in five pigs, and a custom-made nonsutured graft was secured with use of an end-to-end method in five pigs. Femoral anastomoses were performed with the standard open technique. RESULTS: Technical success was achieved in all 10 animals and with no major complications. Mean blood loss was 20 ml (range, 5-50 ml), and mean operative time was 2.45 hours (range, 2-4 hrs). On aortic-clamp release, 2 of the end-to-side anastomoses required additional sutures to stop bleeding between oversized staples, and 2 of the end-to-end anastomoses required additional ties to reinforce loose ties. All 10 grafts and anastomoses were patent and free of leaks after completion of the procedure. CONCLUSIONS: Laparoscopic aortofemoral bypass is technically feasible in a porcine model. Further experimental work with new instrumentation and technical refinement will make laparoscopic surgery feasible for the treatment of vascular disease in humans.

We report resistance data for americium metal under pressure up to 25 GPa and at temperatures down to 1.3 K. Samples of 243 Am with the double-hexagonal-closed-packed (d.h.c.p.) structure and also with the f.c.c. structure at ambient pressure were studied. The superconducting transition temperature of americium is shown to increase in both cases considerably with pressure, reaching a maximum value of 2.3 K at 6.6 GPa in the case of d.h.c.p. americium. The pressure variation of the superconducting critical temperature and the normal state properties of americium metal exhibit several anomalies, which are discussed with respect to phase transitions established by high pressure X-ray crystallography.

Aim: To determine the feasibility of subintimal angioplasty (SIA), aided by reentry device in iliac artery occlusions. Methods: Forty-eight patients with severe claudication (Fontaine-III, n = 24) or critical limb ischaemia (Fontaine-IV, n = 24) had SIA, aided with a reentry device, for chronic iliac occlusions TASC C (n =28) and D (n = 20). The primary outcome was arterial patency at duplex follow-up. Secondary outcomes were primary failure, postprocedural complications, stent use, late occlusions, and length of hospital stay. Results: The patency rate was 89% at a mean follow-up of 13 (±11) months. There were 2 primary failures, no postprocedural complications, and 5 late occlusions. Almost 80% of patients were ready for discharge within 24 hours. Conclusions: Subintimal angioplasty with a reentry device for long iliac occlusions provides a feasible option with excellent results and short hospital stay. A randomized trial of SIA of iliac occlusion versus open reconstruction is now required.

Measurement of the Ce valence in the heavy fermion ${\mathrm{CeCu}}_{2}{\mathrm{Si}}_{2}$ is reported for the first time under pressure and at low temperature ($T=14\text{ }\text{ }\mathrm{K}$) in proximity of the superconducting region. ${\mathrm{CeCu}}_{2}{\mathrm{Si}}_{2}$ is considered as a strong candidate for a new type of pairing mechanism related to critical valence fluctuations which could set in at high pressure in the vicinity of the second superconducting dome. A quantitative estimate of the valence in this pressure region was achieved from the measurements of the Ce ${L}_{3}$ edge in the high-resolution partial-fluorescence yield mode and subsequent analysis of the spectra within the Anderson impurity model. While a clear increase of the Ce valence is found, the weak electron transfer and the continuous valence change under pressure suggests a crossover regime with the hypothetical valence line terminating at a critical end point ${T}_{\mathrm{cr}}$ close to zero.

The aim of this article is to discuss recent developments in the management of venous disease. A literature search was done of English language journals from 1995 to 2000 to identify articles that discussed new innovations. In addition, the proceedings of specialist meetings were reviewed to include opinions of experts leading the field of venous practice. The article discusses the use of non-invasive investigations, thermal ablation of varicose veins, the economics of superficial and deep venous disease and the possible changes that might occur in the future management of patients with venous disease.