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Background: There is a paucity of knowledge on the long-term outcome in patients diagnosed with COVID-19. We describe a cohort of patients with a constellation of symptoms occurring four weeks after diagnosis causing different degrees of reduced functional capacity. Although different hypothesis have been proposed to explain this condition like persistent immune activation or immunological dysfunction, to date, no physiopathological mechanism has been identified. Consequently, there are no therapeutic options besides symptomatic treatment and rehabilitation., Methods: We evaluated patients with symptoms that persisted for at least 4 weeks after COVID-19. Epidemiological and clinical data were collected. Blood tests, including inflammatory markers, were conducted, and imaging studies made if deemed necessary. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reverse transcription polymerase chain reaction (RT-PCR) in plasma, stool, and urine were performed. Patients were offered antiviral treatment (compassionate use)., Results: We evaluated 29 patients who reported fatigue, muscle pain, dyspnea, inappropriate tachycardia, and low-grade fever. Median number of days from COVID-19 to positive RT-PCR in extra-respiratory samples was 55 (39-67). Previous COVID-19 was mild in 55% of the cases. Thirteen patients (45%) had positive plasma RT-PCR results and 51% were positive in at least one RT-PCR sample (plasma, urine, or stool). Functional status was severely reduced in 48% of the subjects. Eighteen patients (62%) received antiviral treatment. Improvement was seen in most patients (p = 0.000) and patients in the treatment group achieved better outcomes with significant differences (p = 0.01)., Conclusions: In a cohort of COVID-19 patients with persistent symptoms, 45% of them have detectable plasma SARS-CoV-2 RNA. Our results indicate possible systemic viral persistence in these patients, who may benefit of antiviral treatment strategies., (© 2022. The Author(s).)

The thermoelectric behavior and stability of Cu 2 SnS 3 (CTS) has been investigated in relation to different preparations and sintering conditions, leading to different microstructures and porosities. The studied system is CTS in its cubic polymorph, produced in powder form via a bottom-up approach based on high-energy reactive milling. The as-milled powder was sintered in two batches with different synthesis conditions to produce bulk CTS samples: manual cold pressing followed by traditional sintering (TS), or open die pressing (ODP). Despite the significant differences in densities, ~75% and ~90% of the theoretical density for TS and ODP, respectively, we observed no significant difference in electrical transport. The stable, best performing TS samples reached zT ~0.45, above 700 K, whereas zT reached ~0.34 for the best performing ODP in the same conditions. The higher zT of the TS sintered sample is due to the ultra-low thermal conductivity ( κ ~0.3-0.2 W/mK), three-fold lower than ODP in the entire measured temperature range. The effect of porosity and production conditions on the transport properties is highlighted, which could pave the way to produce high-performing TE materials.

Introduction: Since the SARS-CoV-2 pandemics began, multiple cases of Guillain-Barre syndrome secondary to COVID-19 have been described. Its typical presentation consists of the triad of paresthesia, ascending muscle weakness and areflexia, although there are several regional variants such as facial diplegia., Case Presentation: Two weeks after a contact with a confirmed case of COVID-19, a 35-year-old woman presents with viral myopericarditis. Laboratory studies for autoimmune diseases come back negative, as well as multiple viral serologies. She presents anti-SARS-CoV-2 IgG, with negative PCR. A week after discharge she presents with palsy of both facial nerves, without other neurological abnormalities. She undergoes examination with cranial CT without findings, and an EMG which shows bilateral alteration of facial nerves. She refuses the performance of a lumbar puncture., Discussion: Facial diplegia can occur because of several illnesses, such as meningeal or brainstem tumors, infectious agents, Guillain-Barre syndrome, autoimmune diseases, trauma, metabolic causes or congenital causes. In our patient, having discarded other etiologies with imaging and analytical studies, the most probable cause is the Guillain-Barre syndrome. It is possibly secondary to SARS-CoV-2 infection given the presence of anti-SARS-CoV-2 IgG antibodies after contact with a confirmed case., Conclusion: This case supports the hypothesis that COVID-19 may trigger the Guillain-Barre syndrome, specifically as facial diplegia, which is an atypical variant that should be known to be early diagnosed and treated as part of this syndrome., (Universidad Nacional de Córdoba)

We present the first candidate for the realization of a disorder-induced Topological Anderson Insulator in a real material system. High-energy reactive mechanical alloying produces a polymorph of Cu 2 ZnSnS 4 with high cation disorder. Density functional theory calculations show an inverted ordering of bands at the Brillouin zone center for this polymorph, which is in contrast to its ordered phase. Adiabatic continuity arguments establish that this disordered Cu 2 ZnSnS 4 can be connected to the closely related Cu 2 ZnSnSe 4 , which was previously predicted to be a 3D topological insulator, while band structure calculations with a slab geometry reveal the presence of robust surface states. This evidence makes a strong case in favor of a novel topological phase. As such, the study opens up a window to understanding and potentially exploiting topological behavior in a rich class of easily-synthesized multinary, disordered compounds.

The present work focused on the microstructural, thermal, electrical, and damping characterization of NiMnGa samples produced through a powder pressing and a sintering process; the effect of sintering times and of the starting powder size were evaluated. Moreover, an observation of the evolution of martensitic transformation typical of NiMnGa ferromagnetic shape memory alloy was conducted in comparison with the cast material behavior and in correlation with the material densification. The optimum powder size and sintering time for the process, i.e., 50 µm or lower and 72 h, were identified considering the investigated physical properties of the sintered samples in comparison to the cast material. The corresponding sample showed the best compromise between density, thermal and electrical properties, and damping and functional behaviour. In general, the outcomes of this study could be the basis of a useful tool for production processes that include a sintering step as well as being a starting point for the evaluation of an alternative low cost fabrication method of this alloy.

Lymphogranuloma venereum (LGV) is a sexually transmitted infection caused by invasive serovars of Chlamydia trachomatis. There have been only a few case reports of oropharyngeal C. trachomatis infection complicated with cervical LGV. We report a case of a HIV-positive male patient with cervical LGV that presented a poor evolution despite appropriate treatment.

Background: Mitochondrial DNA (mtDNA) haplogroups have been associated with advanced liver fibrosis and cirrhosis in patients coinfected with human immunodeficiency virus (HIV) and hepatitis C virus (HCV). Our aim was to determine whether mtDNA haplogroups are associated with liver-related events (LREs) in HIV/HCV-coinfected patients., Methods: We carried out a retrospective cohort study in HIV/HCV-coinfected patients who were potential candidates for therapy with interferon and ribavirin (IFN/Rib) between 2000 and 2009. The primary endpoint was the occurrence of LREs (decompensation or hepatocellular carcinoma). mtDNA genotyping was performed using the Sequenom MassARRAY platform. We used Fine and Gray proportional hazards model to test the association between mtDNA haplogroups and LREs, considering death as a competitive risk., Results: The study population comprised 243 patients, of whom 40 had advanced fibrosis or cirrhosis. After a median follow-up of 7.7 years, 90 patients treated with IFN/Rib achieved sustained viral response (SVR), 18 patients had LREs, and 11 patients died. Patients with haplogroup H had lower cumulative incidence than patients with other haplogroups (p = 0.012). However, patients with haplogroup T had higher cumulative incidence than patients with other haplogroups (p = 0.074). In the multivariate analysis, haplogroup T was associated with an increased hazard of developing LREs [adjusted subhazard ratio (aSHR) = 3.56 (95% CI 1.13;11.30); p = 0.030]; whereas haplogroup H was not associated with lower hazard of LREs [aSHR = 0.36 (95% CI 0.10;1.25); p = 0.105]. When we excluded patients who achieved SVR during follow-up, we obtained similar SHR values., Conclusions: European mitochondrial haplogroups may influence the natural history of chronic hepatitis C.

Bulk samples of kesterite (Cu 2 ZnSnS 4 , CZTS) were produced by cold-pressing and sintering of CZTS powders obtained via reactive ball-milling. An increase in the Seebeck coefficient of more than 100 μV/K, almost doubling the expected value, is noticed around a temperature of 260 °C. As pointed out by thermal analyses, this is due to a second order transition of kesterite from an ordered I-4 to a disordered I-42m crystal structure. Conversely to what happens for solar cell materials, where the transition is considered to be detrimental for the performance, it appears to be beneficial for the thermoelectric Seebeck coefficient, suggesting that higher crystal symmetry and cation-disorder due to the transition lead to thermopower enhancement., Competing Interests: The authors declare no conflict of interest.

The incidence of stroke in human immunodeficiency virus (HIV)-infected individuals has been well analyzed in recent epidemiological studies. However, little is known about the specific contribution of hepatitis C virus (HCV) infection to stroke among HIV-infected individuals. The aims of this study were to analyze trends in the incidence rates of stroke in HIV-infected individuals during the combination antiretroviral (cART) era in Spain and to categorize them by the presence or absence of HCV coinfection. We analyzed hospital discharges with a diagnosis of stroke in Spain according to ICD-9-CM during 1997-2013. The study period was divided into four calendar periods (1997-1999, 2000-2003, 2004-2007, and 2008-2013). Patients were classified according to HCV serology. The number of HIV-infected patients was estimated based on data from the National Centre of Epidemiology. We calculated incidence rates (events per 10,000 patient-years) and in-hospital case fatality rates (CFR). The incidence of hemorrhagic stroke (HS) decreased in HIV-monoinfected patients (15.8 [1997-1999] to 6.5 [2008-2013]; P<0.001) and increased in HIV/HCV-coinfected patients (1.3 [1997-1999] to 5.5 [2008-2013]; P<0.001). The incidence of ischemic stroke (IS) decreased in HIV-monoinfected patients (27.4 [1997-1999] to 21.7 [2008-2013]; P = 0.005) and increased in HIV/HCV-coinfected patients (1.8 [1997-1999] to 11.9 [2008-2013]; P<0.001). The CFR was 3.3 times higher for HS than for IS for the whole study period. The CFR of HS in HIV-monoinfected patients decreased significantly (47.4% [1997-1999] to 30.6% [2008-2013]; P = 0.010) but did not change significantly among HIV/HCV-coinfected patients (41.4% [1997-1999] to 44.7% [2008-2013]; P = 0.784). The CFR of IS in the whole HIV-infected population decreased significantly (14.6% [1997-1999] to 10.9% [2008-2013]; P = 0.034), although no significant differences were found when each group was analyzed separately. In conclusion, after the introduction of cART, HS and IS rates decreased in HIV-monoinfected individuals, but increased steadily in HIV/HCV-coinfected individuals.

Outstanding ZT values registered on single crystals recently renewed the interest of thermoelectric community for SeSn compound. Owing to the strong anisotropy of the phenomenon, so far only single crystals proved to be the suitable for its application. Here we present the production and the characterization of bulk polycrystalline materials processed by open die pressing, aimed at reducing the gap with single crystal materials by taking advantage from the highly texture degree derived by the processing and by the improved phonon scattering promoted by grain boundaries. The resulting bulks display good compaction, improved mechanical properties and strong texture of the phase. Structural and morphological analyses confirmed the successful orientation according to the (400) cleavage plane. The structural transition responsible for the ultra-low thermal conductivity has been investigated and possible irreversible effects on the starting phase due to thermal cycling have been evaluated. Preliminary measurements of thermal conductivity are reported.

Nowadays, a big challenge in the thermoelectric field is the identification of efficient thermoelectric materials but inexpensive, easy to synthesize, and comprised of Earth-abundant elements. On this basis, tetrahedrite mineral family (Cu(12−x)Tr(x)Sb₄S₁₃ where Tr = Cu, Mn, Fe, Co, Ni, Zn) seems to be an attractive p-Type Pb-free thermoelectric material, showing a relatively high conversion efficiency. In this work, a solvothermal synthesis method was developed for undoped tetrahedrite Cu₁₂Sb₄S₁₃ and the introduction of Zn and Ni as substituents of copper was also tested. The influence of the stoichiometry and the synthesis conditions on the tetrahedrite phase content and density of the samples were investigated by X-ray diffraction (with profile Rietveld refinements) and scanning electron microscope (equipped with energy dispersive X-ray spectroscopy). Preliminary sintering test were performed by Open Die Pressing.

In this work the thermoelectric generator (TEG) based on catalytic combustion already developed in our lab has been further investigated and improved. The system made of two thermoelectric (TE) modules coupled with a catalytic combustor has been used in this work to obtain higher overall efficiency by adding hydrogen to the fuel mixture. Since implementation of hydrogen as a fuel has shown low and stable combustion temperature in literature, it is expected to achieve good overall efficiency of TEG. Moreover, hydrogen can be used to improve the system inducing self-ignition. Focus of the present work is the implementation of different mixture proportions, varying the amount of hydrogen, and the investigation of their effects on the overall efficiency. The overall TEG efficiency, has been evaluated by parallel characterization of thermoelectric modules and exhaust gases composition. The system performances have been characterized using different mixtures: the results indicate that addition of H₂ to the fuel contribute to increase the chemical and overall TEG efficiency respect to previous work, producing up to 5.92 W of electrical power. Finally, the effects of H₂ for on self-ignition conditions have been investigated finding the minimum H₂ amount for different gas flow rates.

Background: Leprosy remains infrequent in non-endemic areas. The objective of this study was to describe the cases of leprosy reviewed at a referral unit for imported diseases in Europe and to compare these findings with published data on imported leprosy., Methods: Cases of leprosy evaluated at a referral centre are described and salient features of autochthonous and imported cases are compared. A review of the literature on imported leprosy was performed., Results: During the study period, 25 patients with leprosy were followed-up (10 were autochthonous cases and 15 were considered to be imported). Regarding imported cases, the majority were diagnosed in Latin American immigrants (10/15, 67%), mean age was 42 years, there were no differences in gender distribution, estimated average time from arrival in Spain to first visit at the unit was 3 years and from symptom onset to diagnosis was 2 years. Over 80% of imported cases had multibacillary disease and over one third of patients had been previously diagnosed with leprosy. One third had received alternate incorrect diagnoses initially, <50% of patients with imported leprosy completed standard therapy and were considered cured and over one third were lost to follow-up., Conclusions: Leprosy remains a complex disease for healthcare professionals unfamiliar with this infection. Manifestations are polymorphic so misdiagnoses and consequent delays in diagnosis are not infrequent and may lead to resulting disabilities. Early diagnosis and management are essential to prevent sequelae and possible transmission. Improving access to health care, especially for vulnerable groups, would be necessary to advance in the control of this disease., (Copyright © 2016 Elsevier Ltd. All rights reserved.)