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We present an investigation into the vertical transport through 13 different superlattice structures, where the well and barrier widths, doping concentration, dopant position, and contact layers were varied. Although superlattices have been extensively studied since 1970, there is a lack of publications on transport through superlattices similarly low doped as THz quantum cascade lasers (QCLs), for which the doping is in the 3-5×10^{10}  cm^{-2} range. The superlattices presented are doped in the same range as THz QCLs, with contact layers and fabrication comparable to high-temperature THz QCLs. The temperature-dependent current-voltage characteristics were measured starting from 5 K and an anomalous temperature effect was observed at the first plateau. The measured current through the superlattice first decreases before increasing again with increasing temperature, resulting in the lowest current occurring at 75-110 K. This behavior is also observed in some THz QCLs. The effect disappears for thinner barriers, higher quantum well doping, or modified contact layers, indicating a strong dependency on band bending, due to the large difference in the doping of the contact layers and the superlattice, which is confirmed with multiscattering Büttiker simulations.

InAs/AlSb quantum cascade detectors (QCDs) grown strain-balanced on GaSb substrates are presented. This material system offers intrinsic performance-improving properties, like a low effective electron mass of the well material of 0.026 m 0 , enhancing the optical transition strength, and a high conduction band offset of 2.28 eV, reducing the noise and allowing for high optical transition energies. InAs and AlSb strain balance each other on GaSb with an InAs:AlSb ratio of 0.96:1. To regain the freedom of a lattice-matched material system regarding the optimization of a QCD design, submonolayer InSb layers are introduced. With strain engineering, four different active regions between 3.65 and 5.5 µm were designed with InAs:AlSb thickness ratios of up to 2.8:1, and subsequently grown and characterized. This includes an optimized QCD design at 4.3 µm, with a room-temperature peak responsivity of 26.12 mA/W and a detectivity of 1.41 × 10 8  Jones. Additionally, all QCD designs exhibit higher-energy interband signals in the mid- to near-infrared, stemming from the InAs/AlSb type-II alignment and the narrow InAs band gap., Competing Interests: Conflict of interest: Authors state no conflicts of interest., (© 2024 the author(s), published by De Gruyter, Berlin/Boston.)

The 2D form of tellurium, named tellurene, is one of the latest discoveries in the family of 2D mono-elemental materials. In a trilayer configuration, free-standing tellurene was predicted theoretically to acquire two crystallographic forms, the α and β phases, corresponding to either a 1T-MoS 2 -like geometry or a trilayer slab exposing the Te(101̄0) surface of bulk Te with helical chains lying in-plane and further reconstructed due to the formation of interchain bonds. Either one or the other of the two phases was observed experimentally to prevail depending on the substrate they were grown onto. In the perspective to integrate tellurene on silicon, we here report an ab initio study of the adsorption of tellurene on the Si(111)- R 30° surface passivated by antinomy. According to the literature, this substrate is chosen for the growth of several tellurides by molecular beam epitaxy. The calculations reveal that on this substrate the adsorption energy mostly compensates the energy difference between the α and β phases in the free-standing configuration which suggests that the prevalence of one phase over the other might in this case strongly depend on the kinetics effects and deposition conditions.

Background: There are limited data concerning procedure-related complications of endovascular thrombectomy for large vessel occlusion strokes., Aims: We evaluated the cumulative incidence, the clinical relevance in terms of increased disability and mortality, and risk factors for complications., Methods: From January 2011 to December 2017, 4799 patients were enrolled by 36 centers in the Italian Registry of Endovascular Stroke Treatment. Data on demographic and procedural characteristics, complications, and clinical outcome at three months were prospectively collected., Results: The complications cumulative incidence was 201 per 1000 patients undergoing endovascular thrombectomy. Ongoing antiplatelet therapy (p < 0.01; OR 1.82, 95% CI: 1.21-2.73) and large vessel occlusion site (carotid-T, p < 0.03; OR 3.05, 95% CI: 1.13-8.19; M2-segment-MCA, p < 0.01; OR 4.54, 95% CI: 1.66-12.44) were associated with a higher risk of subarachnoid hemorrhage/arterial perforation. Thrombectomy alone (p < 0.01; OR 0.50, 95% CI: 0.31-0.83) and younger age (p < 0.04; OR 0.98, 95% CI: 0.97-0.99) revealed a lower risk of developing dissection. M2-segment-MCA occlusion (p < 0.01; OR 0.35, 95% CI: 0.19-0.64) and hypertension (p < 0.04; OR 0.77, 95% CI: 0.6-0.98) were less related to clot embolization. Higher NIHSS at onset (p < 0.01; OR 1.04, 95% CI: 1.02-1.06), longer groin-to-reperfusion time (p < 0.01; OR 1.05, 95% CI: 1.02-1.07), diabetes (p < 0.01; OR 1.67, 95% CI: 1.25-2.23), and LVO site (carotid-T, p < 0.01; OR 1.96, 95% CI: 1.26-3.05; M2-segment-MCA, p < 0.02; OR 1.62, 95% CI: 1.08-2.42) were associated with a higher risk of developing symptomatic intracerebral hemorrhage compared to no/asymptomatic intracerebral hemorrhage. The subgroup of patients treated with thrombectomy alone presented a lower risk of symptomatic intracerebral hemorrhage (p < 0.01; OR 0.70; 95% CI: 0.55-0.90). Subarachnoid hemorrhage/arterial perforation and symptomatic intracerebral hemorrhage after endovascular thrombectomy worsen both functional independence and mortality at three-month follow-up (p < 0.01). Distal embolization is associated with neurological deterioration (p < 0.01), while arterial dissection did not affect clinical outcome at follow-up., Conclusions: Complications globally considered are not uncommon and may result in poor clinical outcome. Early recognition of risk factors might help to prevent complications and manage them appropriately in order to maximize endovascular thrombectomy benefits.

Background: Occlusion of the internal carotid artery (ICA), whether isolated or in the setting of a tandem lesion (TL) have a poor response to treatment with intravenous thrombolysis. Previous studies ​​have demonstrated the superiority of mechanical thrombectomy in the treatment of acute ischemic stroke (AIS) following large vessel occlusion, compared to standard intravenous fibrinolysis. The aim of our study was to describe endovascular treatment (EVT) in AIS due to isolated ICA occlusion or TL., Methods: We assessed the association between 90-day outcome and clinical, demographic, imaging, and procedure data in 51 consecutive patients with acute isolated ICA occlusion or TL who underwent EVT. We evaluated baseline NIHSS and mRS, ASPECTS, type of occlusion, stent placement, use of stent retrievers and/or thromboaspiration, duration of the procedure, mTICI, postprocedural therapy and complications., Results: A favorable 90-day outcome (mRS 0-2) was achieved in 34 patients (67 %) and was significantly associated with the use of dual antiplatelet therapy after the procedure (p = 0.008), shorter procedure duration (p = 0.031), TICI 2b-3 (p < 0.001) and lack of post-procedural hemorrhagic transformation (p = 0.001). Four patients did not survive, resulting in a mortality rate of 8 %., Conclusions: Our study has shown that EVT in the treatment of AIS due to ICA occlusion is safe, and effective in determining a good functional outcome. ICA stenting led to good angiographic results and therapy with a glycoprotein IIb / IIIa inhibitor immediately after stent release did not result in a greater risk of hemorrhage. The use of post-procedural dual antiplatelet therapy was associated with favorable outcome, without a significant increase in hemorrhagic transformation., (© 2021. The Author(s).)

Spontaneous intracranial hypotension results from a spinal CSF leak and usually presents with orthostatic headache, although acephalgic presentations have anecdotally been reported. The underlying low CSF volume, rarely, leads to serious complications such as cerebral venous thrombosis and coma. We report a patient presenting with cerebral venous thrombosis secondary to acephalgic spontaneous intracranial hypotension. An epidural blood patch was performed; nonetheless, the patient intracracal condition deteriorated to coma and neuroimages showed a deep brain swelling with midbrain distortion, subsequently complicated by intracranial pontine hemorrhage.

Non-operative management (NOM) of hemodynamically stable patients with blunt splenic injury (BSI) is the standard of care, although it is associated with a potential risk of failure. Hemodynamically unstable patients should always undergo immediate surgery and avoid unnecessary CT scans. Angioembolization might help to increase the NOM rates, as well as NOM success rates. The aim of this study was to review and critically analyze the data from BSI cases managed at the Maggiore Hospital Trauma Center during the past 5 years, with a focus on NOM, its success rates and outcomes. A further aim was to develop a proposed clinical practical algorithm for the management of BSI derived from Clinical Audit experience. During the period between January 1, 2009 and December 31, 2013 we managed 293 patients with splenic lesions at the Trauma Center of Maggiore Hospital of Bologna. The data analyzed included the demographics, clinical parameters and characteristics, diagnostic and therapeutic data, as well as the outcomes and follow-up data. A retrospective evaluation of the clinical outcomes through a clinical audit has been used to design a practical clinical algorithm. During the five-year period, 293 patients with BSI were admitted, 77 of whom underwent immediate surgical management. The majority (216) of the patients was initially managed non-operatively and 207 of these patients experienced a successful NOM, with an overall rate of successful NOM of 70 % among all BSI cases. The success rate of NOM was 95.8 % in this series. All patients presenting with stable hemodynamics underwent an immediate CT-scan; angiography with embolization was performed in 54 cases for active contrast extravasation or in cases with grade V lesions even in absence of active bleeding. Proximal embolization was preferentially used for high-grade injuries. After a critical review of the cases treated during the past 5 years during a monthly clinical audit meeting, a clinical algorithm has been developed with the aim of standardizing the clinical management of BSI by a multidisciplinary team to include every patient within the correct diagnostic and therapeutic pathway, in order to improve the outcomes by potentially decreasing the NOM failure rates and to optimize the utilization of resources.

A case of superior vena cava thrombosis secondary to the thoracic outlet syndrome is reported. The diagnosis was revealed by CT-scan and confirmed by phlebography performed to insert a catheter for intrathrombotic infusion of urokinase. The thrombolytic treatment was followed by complete clot lysis. A hyperabduction manoeuvre confirmed costoclavicular compression as the cause of the subclavian-axillary vein thrombosis for which the patient underwent first rib resection. Axillary-subclavian vein thrombosis (or Paget-von Schroetter syndrome) is a relatively frequent complication of the thoracic outlet syndrome often treated with anticoagulants on the basis of a duplex examination. Involvement of the superior vena cava is not readily detected by duplex ultrasound so a partial thrombosis, with a possible fatal outcome could remain undiagnosed. Full investigation by phlebography or CT-scan is therefore recommended. In addition, transcatheter thrombolytic therapy has a lower incidence of follow-up complications than heparin.

This study was aimed at retrospectively assessing the effectiveness of transarterial chemoembolization by reviewing our six years' experience. From January, 1988, to December, 1993, chemoembolization was performed in more than 400 patients. Of them, 321 patients with complete follow-up were selected. The treatment was retrospectively analyzed according to survival rates. The average survival of chemoembolized patients is 12 months after the first treatment session. Average survival rates in Child A, B and C patients were, respectively, 13.79, 11.2 and 6.01 months. The patients were also divided according to tumor spread and the results follow: patients with single localizations had 15.19 months' survival, those with multiple localization 12.06 and those with tumor spread had 9.51 months' survival. The patients were divided into two groups: complete chemoembolization (group A) and incomplete chemoembolization (group B). The average survival was 15.95 months for 160 group A patients and 10.11 months for 161 group B patients. As for the number of chemoembolization sessions, 123 patients underwent only one session, 112 patients two sessions, 70 patients three, 12 patient four and 4 patients five sessions--625 sessions in all. Chemoembolization was performed every 3-4 months and was always preceded by a CT exam. Our patients were compared with an untreated group where average survival was 6.32 months. The value of CT after the first treatment in predicting survival was also studied. Finally, the methods used in all treatment are reported on, together with the general results and those in the different classes of patients.

The authors report their experience with angiographic techniques in the diagnosis of vascular complications after liver transplantation. From 1986 to 1990, 78 patients were transplanted in our Hospital; of them, 8 underwent angiographic investigations for vascular complications. Angiography is very important when vascular complications are suspected, in the patients with a rise in cytolytic enzymes and in bilirubine levels, with hyperpyrexia, and with bioptic confirmation of no rejection. Duplex US is useful in the evaluation of portal canalization; if there are any doubts, angiography is performed also in the preoperative phase.