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Half-metallic semiconductors typically exhibit 100% spin polarization at the Fermi level which makes them desired materials for spintronic applications. In this study, we reported a half-metallic ferromagnetic nature in vacancy-ordered double perovskites Tl2WX6 (X = Cl and Br). The magnetic, electronic, and thermoelectric properties of the material are studied by the use of density functional theory (DFT). For the calculations of exchange-correlation potential, PBE-sol is employed while more accurate electronic band structure and density of states (DOS) are calculated by the mBJ potential. Both materials exhibited structural stability in the cubic structure with Fm3Ìm space-group. The mechanical stability is confirmed by their computed elastic constants while their thermodynamic stability is attested by negative formation energy. The spin-based volume optimization suggested the ferromagnetic nature of the materials which is further confirmed by the negative value of the exchange energy Δ x(pd). Moreover, computed magnetic moment value for Tl2WCl6 and Tl2WBr6 is 2 µB and the majority of this comes from W. The spin-polarized band structure and DOS confirmed that both materials are half-metallic and at the Fermi level they exhibit 100% spin polarization. Furthermore, in the spin-down state, materials behave as semiconductors with wide bandgaps. Lastly, the thermoelectric properties are evaluated by the BoltzTrap code. The thermoelectric parameters which include the Seebeck coefficient, electrical conductivity, thermal conductivity, power factor, and figure of merit (ZT) are investigated in the range of temperatures from 200 to 800 K. The half-metallic ferromagnetic and thermoelectric characteristics make these materials desired for spintronics and thermoelectric applications.
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Efficient conversion of solar power to electrical power through the development of smart, reliable, and environmentally friendly materials is a key focus for the next-generation renewable energy sector. The involvement of degradable and toxic elements present in hybrid perovskites presents serious concerns regarding the commercial viability of these materials for the solar cell industry. In this study, a solar cell with a stable, nondegradable, and lead-free halide-based double perovskite Cs2AgBiBr6 as the absorber layer, Cu2O as a hole transport layer, and GO as the electron transport layer has been simulated using SCAPS 1D. The thickness of the absorber, electron transport, and hole transport layers are tuned to optimize the performance of the designed solar cell. Notably, perovskite solar cells functioned most efficiently with an electron affinity value of 4.0 eV for Cu2O. In addition, the effect of variation of series resistance and temperature on generation and recombination rates, current density, and quantum efficiency has been elaborated in detail. The findings of this study provide valuable insight and encouragement toward the realization of a non-toxic, inorganic perovskite solar device and will be a significant step forward in addressing environmental concerns associated with perovskite solar cell technology.
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The manipulation of electronic device characteristics through electron spin represents a burgeoning frontier in technological advancement. Investigation of magnetic and transport attributes of the Tl2Mo(Cl/Br)6 double perovskite was performed using Wien2k and BoltzTraP code. When the energy states between ferromagnetic and antiferromagnetic conditions are compared, it is evident that the ferromagnetic state exhibits lower energy levels. Overcoming stability challenges within the ferromagnetic state is achieved through the manipulation of negative ΔHf within the cubic state. The analysis of the half metallicity character involves an analysis of band structure (BS) and DOS, elucidating its mechanism through PDOS using double exchange model p-d hybridization. The verification of 100% spin polarization is confirmed through factors such as spin polarization and the integer value of the total magnetic moment. Furthermore, the thermoelectric response, as indicated by the ratios of thermal-electrical conductivity and ZT, underscores the promising applications of these compounds in thermoelectric device applications.
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This comprehensive review critically examines the UK medical curriculum, with a particular focus on progress testing as an innovative assessment strategy. The curriculum, evolving from foundational sciences to practical applications, is encapsulated in the integrated curriculum model (ICM). This model adeptly combines theoretical knowledge with clinical practice, fostering cognitive, affective, and psychomotor skills among medical students. Central to this review is an exploration of progress testing. This method, grounded in constructivist learning theories, emphasises continuous assessment and professional development. Progress testing's regular, comprehensive examinations are instrumental in guiding students through the progressive stages of competence, as outlined in Miller's pyramid, from foundational knowledge to clinical proficiency. The review also addresses the broader impacts of progress testing on teaching approaches, student feedback, academic and pastoral support, and quality assurance. By aligning with the dynamic requirements of 21st-century medical training, progress testing not only nurtures well-rounded professionals but also ensures compliance with regulatory bodies like the General Medical Council. Its emphasis on continuous evaluation aligns with the practical realities of a medical career, driving curricular innovation and aligning with regulatory standards. The implementation of progress testing marks a significant advancement in medical education. Its continuous, holistic nature benefits both students and educators, nurturing a more engaged learning attitude and meeting evolving medical needs. The adoption of this assessment strategy is seen as pivotal in shaping competent medical professionals, ready to face the challenges of modern medical practice.
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BACKGROUND: Noncompliance with evidence-based interventions and guidelines contributes to significant and variable recurrence and progression in patients with non-muscle-invasive bladder cancer (NMIBC). The implementation of a quality performance indicator (QPI) programme in Scotland's National Health Service (NHS) aimed to improve cancer outcomes and reduce nationwide variance. OBJECTIVE: To evaluate the effect of hospitals achieving benchmarks for two specific QPIs on time to recurrence and progression in NMIBC. DESIGN, SETTING, AND PARTICIPANTS: QPIs for bladder cancer (BC) were enforced nationally in April 2014. NHS health boards collected prospective data on all new BC patients. Prospectively recorded surveillance data were pooled from 12 collaborating centres. INTERVENTION: QPIs of interest were (1) hospitals achieving detrusor muscle (DM) sampling target at initial transurethral resection of bladder tumour (TURBT) and (2) use of single instillation of mitomycin C after TURBT (SI-MMC). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary and secondary endpoints were time to recurrence and progression, respectively. Kaplan-Meier and Cox multivariable regression analyses were performed. KEY FINDINGS AND LIMITATIONS: Between April 1, 2014 and March 31, 2017, we diagnosed 3899 patients with new BC, of which 2688 were NMIBC . With a median follow up of 60.3 mo, hospitals achieving the DM sampling target had a 5.4% lower recurrence rate at 5 yr than hospitals not achieving this target (442/1136 [38.9%] vs 677/1528 [44.3%], 95% confidence interval [CI] = 1.6-9.2, p = 0.005). SI-MMC was associated with a 20.4% lower recurrence rate (634/1791 [35.4%] vs 469/840 [55.8%], 95% CI = 16.4-24.5, p < 0.001). On Cox multivariable regression, meeting the DM target and SI-MMC were associated with significant improvement in recurrence (hazard ratio [HR] 0.81, 95% CI = 0.73-0.91, p = 0.0002 and HR 0.66, 95% CI = 0.59-0.74, p < 0.004, respectively) as well as progression-free survival (HR 0.62, 95% CI = 0.45-0.84, p = 0.002 and HR 0.65, 95% CI = 0.49-0.87, p = 0.004, respectively). We did not have a national multicentre pre-QPI control. CONCLUSIONS: Within a national QPI programme, meeting targets for sampling DM and SI-MMC in the real world were independently associated with delays to recurrence and progression in NMIBC patients. PATIENT SUMMARY: Following the first 3 yr of implementing a novel quality performance indicator programme in Scotland, we evaluated compliance and outcomes in non-muscle-invasive bladder cancer. In 2688 patients followed up for 5 yr, we found that achieving targets for sampling detrusor muscle and the single instillation of mitomycin C during and after transurethral resection of bladder tumour, respectively, were associated with delays in cancer recurrence and progression.
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The mammalian snout has Meissner's corpuscles (MCs), which transmit epicritic sensations as the animal explores its surroundings. To comprehend the somatosensory acuity in mammals, we examined the structural organization and density of bovine Meissner-like corpuscles (BMLCs) at various ages and compared the changes with other mammalian MCs. The skin from the snout of cows or oxen (2-11 years old) was obtained and processed through routine histological technique. Five-µm thick sections were prepared, silver stained according to the Bielschowsky technique as modified by Winkelman and Schmidt (Mayo Clinic Proceedings, 1957, 217), and observed under a compound light microscope quantitatively and qualitatively. The glabrous skin of the cow snout consisted of two types of BMLCs: One was a cylindrical or elongated structure found in the dermal papillae. The other type was spherical and developed in the superficial layers of the epidermis. BMLCs consisted of both coarse and fine nerve fibres. In the young, the corpuscle comprised thin nerve fibres with indistinct cell outlines. In adults, nerve fibres in the corpuscles were closely packed, and networks, varicosities and end bulbs were well developed. With advancing age, the MCs attenuated into a disorganized mass of nerve fibres. The bovine snout is a highly evolved somatosensory organ due to its rich nerve supply and functionally resembles the anthropoid fingertip. Somatosensory acuity will be lower in the glabrous bovine skin than in primate glabrous skin of the fingertip, as the nerve terminals within the BMLCs are less elaborate in content and structural complexity.
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Mecanorreceptores , Pele , Feminino , Bovinos , Animais , Mecanorreceptores/fisiologia , Fibras Nervosas , Evolução Biológica , MamíferosRESUMO
Cadmium (Cd) is the most toxic element which may cause serious consequences to microbial communities, animals, and plants. The use of green technologies like phytoremediation employs plants with high biomass and metal tolerance to extract toxic metals from their rooting zones. In the present work, Hydrocotyle umbellata was exposed to five Cd concentrations (2, 4, 6, 8, and 10 µmol) in triplicates to judge its phytoextraction ability. Effects of metal exposure on chlorophyll (Chl), bio-concentration factor (BCF), translocation factor (TF), and electrolyte leakage (EL) were analyzed after 10 days of treatment. Metal-responding genes were also observed through transcriptomic analysis. Roots were the primary organs for cadmium accumulation followed by stolon and leaves. There was an increase in EL. Plants showed various symptoms under increasing metal stress namely, chlorosis, browning of the leaf margins, burn-like areas on the leaves, and stunted growth, suggesting a positive relationship between EL, and programmed cell death (PCD). Metal-responsive genes, including glutathione, expansin, and cystatin were equally expressed. The phytoextraction capacity and adaptability of H. umbellata L. against Cd metal stress was also demonstrated by BCF more than 1 and TF less than 1.
The results of the current study demonstrated that Hydrocotyle umbellata is a good choice for environmental cleanup in areas with mild Cd contamination. According to TF and BCF, the plant demonstrated a considerable uptake of Cd. Additionally, H. umbellata's eligibility as a phytoremediation agent for Cd was supported by the transcription of numerous metal-responsive genes, including glutathione, expansin, cystatin, and other genes associated with growth.
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Biodegradação Ambiental , Cádmio , Poluentes do Solo , Cádmio/metabolismo , Poluentes do Solo/metabolismo , Folhas de Planta/metabolismo , Raízes de Plantas , Transcrição Gênica , Regulação da Expressão Gênica de Plantas , Estresse FisiológicoRESUMO
Extensive investigations have been conducted on the thermoelectric and optoelectronic characteristics of double perovskite compounds using the full potential linearized augmented plane wave (FP-LAPW) approach. Here we investigated Rb2NaGaZ6 (Z = Br, I) to explore its band structure, and electronic, optical and transport properties. Born's stability criteria have confirmed the mechanical stability of these compounds. Analysis of the elastic properties reveals their ductile nature, as indicated by a Poisson coefficient (υ) greater than 0.26 and a Pugh ratio exceeding 1.75 for Rb2NaGaZ6 (Z = Br, I). Computation of the bandgap values shows that both compositions possess a direct bandgap nature, with respective values of 2.90 eV and 1.25 eV. This suggests that substituting Br with I brings the band edges closer together, resulting in a decrease in the bandgap value. The optical properties are assessed based on the absorption coefficient, reflectivity, and dielectric constants. The thermoelectric properties, including thermal and electrical conductivities, power factor (PF), and figure of merit (ZT), are determined using the BoltzTrap code. The ZT values indicate that both compositions exhibit promising potential for various transportation applications.
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Endoscopic retrograde cholangiopancreatography (ERCP) is the most technically demanding endoscopic procedure with significant adverse events that mandate appropriate training, competence and careful decision-making. The American Society for Gastrointestinal Endoscopy (ASGE) and the European Society of Gastrointestinal Endoscopy (ESGE) updated a list of quality indicators and performance measures for pancreatobiliary endoscopy. Nevertheless, real-life data are scarce, especially from developing countries. The study aimed to assess overall quality, procedural success, and indications of ERCP at our center. Methods: An audit of our endoscopy center at the start of the study for quality and performance indicators and a retrospective analysis of the 4 years of the prospectively maintained data of patients who underwent ERCP regarding procedural success and indications was done. Results: The study showed that ERCP is performed by meeting good quality standards, but structured training, sedation practice, and microbiological surveillance are subpar. A total of 3544 procedures were carried out with successful cannulation of the naive papilla in 93%, with 60% of procedures carried out on females, 80.5% of procedures done for benign diseases, and 19.5% on suspected or proven malignancy (47% men and 53% women) with perihilar obstruction being commonest in both sexes (32-33%) followed by carcinoma gallbladder in women (21%) and distal cholangiocarcinoma in men (27%). Among benign diseases (2711), 12% had benign pancreatic diseases, and 64.8% had common bile duct (CBD) stones, with 31% of CBD stones requiring more than one session for clearance. Conclusion: ERCP at our center is performed by meeting quality standards and by competent endoscopists with good procedural success. Improving sedation strategies, microbiological surveillance, and training programs remains an unmet need.
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Defect fluorite structure with A 2 B 2O7 composition exhibits an intense potential for utilization in modern smart electrical devices. Efficient energy storage with low loss factors like leakage current makes them a prominent candidate for energy storage applications. Here we report a series of the form Nd2-2x La2x Ce2O7 with x = 0.0, 0.2, 0.4, 0.6, 0.8, and 1.0, synthesized via a sol-gel auto-combustion route. The fluorite structure of Nd2Ce2O7 is slightly expanded with the incorporation of La without any phase transformation. A gradual replacement of Nd with La causes a decrease in grain size, which increases the surface energy and thus leads to grain agglomeration. The formation of exact composition without any impurity element is confirmed by energy-dispersive X-ray spectra. The polarization versus electric field loops, energy storage efficiency, leakage current, switching charge density, and normalized capacitance, which are considered key features of any ferroelectric material, are comprehensively examined. The highest energy storage efficiency, low leakage current, small switching charge density, and large value of normalized capacitance are observed for pure Nd2Ce2O7. This reveals the enormous potential of the fluorite family for efficient energy storage devices. The temperature-dependent magnetic analysis exhibited very low transition temperatures throughout the series.
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Background: Endoscopic surgery has emerged in recent years as an alternative to conventional microsurgical approaches for removal of intraventricular tumors. Endoports have enhanced tumor access and visualization with a significant reduction in brain retraction. Objective: To evaluate the safety and efficacy of endoport-assisted endoscopic technique for the removal of tumors from the lateral ventricle. Methods: The surgical technique, complications, and postoperative clinical outcomes were analyzed with a review of the literature. Results: Tumors were primarily located in one lateral ventricular cavity in all 26 patients, and extension to the foramen Monro and the anterior third ventricle was observed in seven and five patients, respectively. Except for three patients with small colloid cysts, all other tumors were larger than 2.5 cm. A gross total resection was performed in 18 (69%), subtotal in five (19%), and partial removal in three (11.5%) patients. Transient postoperative complications were observed in eight patients. Two patients required postoperative CSF shunting for symptomatic hydrocephalus. All patients improved on KPS scoring at a mean follow-up of 4.6 months. Conclusions: Endoport-assisted endoscopic technique is a safe, simple, and minimally invasive method to remove intraventricular tumors. Excellent outcomes comparable to other surgical approaches can be achieved with acceptable complications.
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Neoplasias do Ventrículo Cerebral , Neuroendoscopia , Humanos , Neoplasias do Ventrículo Cerebral/cirurgia , Ventrículos Laterais/cirurgia , Neuroendoscopia/instrumentação , Neuroendoscopia/métodosRESUMO
In the original publication [...].
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BACKGROUND: Endovascular stenting of the deep venous system has been proposed as a method to treat patients with symptomatic iliofemoral outflow obstruction. The purpose of this systematic review and meta-analysis was to compare the effectiveness of this treatment at 1-year following the development of dedicated venous stents. METHOD AND RESULTS: We searched MEDLINE and EMBASE for studies evaluating the effectiveness of venous stent placement. Data were extracted by disease pathogenesis: non-thrombotic iliac vein lesions (NIVL), acute thrombotic (DVT), or post-thrombotic syndrome (PTS). Main outcomes included technical success, stent patency at 1 year and symptom relief. A total of 49 studies reporting outcomes in 5154 patients (NIVL, 1431; DVT, 950; PTS, 2773) were included in the meta-analysis. Technical success rates were comparable among groups (97%-100%). There were no periprocedural deaths. Minor bleeding was reported in up to 5% of patients and major bleeding in 0.5% upon intervention. Transient back pain was noted in 55% of PTS patients following intervention. There was significant heterogeneity between studies reporting outcomes in PTS patients. Primary and cumulative patency at 1 year was: NIVL-96% and 100%; DVT-91% and 97%; PTS (stents above the ligament)-77% and 94%, and; PTS (stents across the ligament)-78% and 94%. There were insufficient data to compare patency outcomes of dedicated and nondedicated venous stents in patients with acute DVT. In NIVL and PTS patients, stent patency was comparable at 1 year. There was inconsistency in the use of validated tools for the measurement of symptoms before and after intervention. When reported, venous claudication, improved in 83% of PTS patients and 90% of NIVL patients, and ulcer healing occurred in 80% of PTS patients and 32% of NIVL patients. CONCLUSIONS: The first generation of dedicated venous stents perform comparably in terms of patency and clinical outcomes to non-dedicated technologies at 1 year for the treatment of patients with NIVL and PTS. However, significant heterogeneity exists between studies and standardized criteria are urgently needed to report outcomes in patients undergoing deep venous stenting.
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Procedimentos Endovasculares , Síndrome Pós-Trombótica , Procedimentos Endovasculares/efeitos adversos , Humanos , Síndrome Pós-Trombótica/diagnóstico por imagem , Síndrome Pós-Trombótica/etiologia , Síndrome Pós-Trombótica/terapia , Estudos Retrospectivos , Stents , Resultado do Tratamento , Grau de Desobstrução VascularRESUMO
BACKGROUND: Breast cancer is an uncommon (rare) disease in men, approximately 1% of the total breast cancer cases in the world. By reason of the rare occurrence, there is no clinical or hospital study giving the information about the essential trace and toxic elements in the biological samples of male breast cancer patients. METHODS: The aim of current study was to estimate association among essential trace {zinc (Zn), iron (Fe) and copper (Cu)} and toxic {cadmium (Cd) and lead (Pb)} elements in human biological samples particularly blood, serum, scalp hair, of male breast cancer patients (n = 14, age range 52 - 58 years) residents of Hyderabad, Pakistan. For comparative purposes, the biological samples of referent persons (n = 37) of the same age groups were also be analyzed. Microwave oven mediated digestion method was employed, and digestion of samples was carried out with the help of 2:1 mixture solution of HNO3 (65%) and H2O2 (30%). Atomic absorption spectrometry was employed for the determination of elemental concentrations from the microwave oven employed digested samples. RESULTS: The found average of essential elements (zinc, iron, and copper) in samples of male breast cancer patients was found to be lower, while cadmium and nickel were found to be higher, when compared with samples from referents (p < 0.001). CONCLUSIONS: These data will be helpful for treatment of male breast cancer patients to improve his health and life.
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Neoplasias da Mama Masculina , Oligoelementos , Cádmio/análise , Humanos , Peróxido de Hidrogênio , Masculino , Pessoa de Meia-Idade , Paquistão , Espectrofotometria Atômica , Oligoelementos/análise , ZincoRESUMO
OBJECTIVE: Sofosbuvir/ledipasvir (SOF/LED) is recommended for treatment of genotypes 1, 4, 5 and 6. Despite some preliminary data from the ELECTRON-2 trial regarding use of SOF/LED combination in chronic hepatitis C genotype 3, there are no guidelines recommending this combination in such patients. We conducted this study to evaluate the efficacy of the overall sustained virologic response at 12 weeks (SVR 12) and safety of SOF/LED in chronic hepatitis C genotype 3 infection in our population. METHODS: It was a prospective, hospital-based observational study. All patients with chronic hepatitis C genotype 3 treated with SOF/LED were divided into two groups: patients with cirrhosis and without cirrhosis. Patients without cirrhosis received SOF/LED (90/400 mg) for 12 weeks; however, patients with cirrhosis received treatment for 24 weeks. RESULTS: We enrolled 104 patients with chronic hepatitis C over a period of 24 months. Of the total, 66 were women (63.5%) and 38 were men (36.5%). The average age was 40 years (range: 18-76 years). Of 104 patients, 86 (82.7%) were of genotype 3, 15 (14.9%) were of genotype 1 and 3 (2.9%) were of genotype 4. Ninety-two (88%) were noncirrhotic and 12 (11.5%) were cirrhotic. Ninety-five (95.2%) were treatment naïve. Among genotype 1 and 4, all patients achieved rapid virologic response and SVR 12. Of 86 genotype 3 patients, 78 (90.6%) were noncirrhotic and 8 (9.3%) were cirrhotic. Among genotype 3 patients without cirrhosis, 75 (96%) achieved SVR 12 while 6 (75%) with cirrhosis achieved SVR 12. All patients tolerated the combination well; however, some patients experienced nausea (26%), headache (25%) and fatigue (21%). No patient had to discontinue therapy due to adverse drug reactions. CONCLUSIONS: Single tablet LED and SOF combination is safe and effective in genotype 3 patients without cirrhosis even without ribavirin. Being effective in genotype 3, the combination can be used as a pangenotypic drug in patients without cirrhosis.
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Giant cell myocarditis is a rare, often rapidly progressive and potentially fatal, disease due to T-cell lymphocyte-mediated inflammation of the myocardium that typically affects young and middle-aged adults. Frequently, the disease course is marked by acute heart failure, cardiogenic shock, intractable ventricular arrhythmias, and/or heart block. Diagnosis is often difficult due to its varied clinical presentation and overlap with other cardiovascular conditions. Although cardiac biomarkers and multimodality imaging are often used as initial diagnostic tests, endomyocardial biopsy is required for definitive diagnosis. Combination immunosuppressive therapy, along with guideline-directed medical therapy, has led to a paradigm shift in the management of giant cell myocarditis resulting in an improvement in overall and transplant-free survival. Early diagnosis and prompt management can decrease the risk of transplantation or death, which remain common in patients who present with cardiogenic shock.
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Células Gigantes/patologia , Miocardite/terapia , Algoritmos , Biomarcadores/sangue , Biópsia , Fármacos Cardiovasculares/uso terapêutico , Desfibriladores Implantáveis , Eletrocardiografia , Endocárdio/patologia , Coração/diagnóstico por imagem , Transplante de Coração , Coração Auxiliar , Humanos , Imunossupressores/uso terapêutico , Miocardite/diagnóstico , Peptídeo Natriurético Encefálico/sangue , Troponina I/sangueRESUMO
BACKGROUND: Tuberculum sellae (TS) meningiomas are benign lesions that produce neurological deficits through a mass effect on vital neurovascular structures. The treatment of choice is surgical removal with the ultimate goal to improve vision and achieve total tumor removal. OBJECTIVE: We analyzed clinical features, tumor characteristics, and surgical approaches in 62 consecutive patients with TS meningiomas to identify factors influencing the postoperative outcome. METHODS: The authors reviewed the medical records of all patients of TS meningiomas who underwent surgery at our institute between 2005 and 2018. Pre- and postoperative clinical data, including the operative findings, of these patients were analyzed. RESULTS: Sixty-two patients who underwent surgery for removal of TSM, transcranial (TCA) in 38, and endoscopic endonasal (EEA) in 24, were identified. Gross total resection was performed in 84% and 87.5% patients in the TCA and EEA groups, respectively. A significantly higher rate of visual improvement was observed in the EEA group as compared to TCA (96% versus 79%). Visual worsening after surgery was greater with TCA than EEA (21% versus 4%). Fourteen (37%) patients in the TCA group experienced different postoperative complications, and CSF leak was the main complication in the EEA group. CONCLUSIONS: TCA and EEA are both associated with higher rates of GTR and visual improvement without compromising the safety of the procedure. An optimal outcome, however, depends on the careful selection of cases based on the tumor location and morphology, and the surgeon's familiarity with the surgical approach.
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Neoplasias Meníngeas , Meningioma , Neuroendoscopia , Neoplasias da Base do Crânio , Humanos , Neoplasias Meníngeas/cirurgia , Meningioma/cirurgia , Procedimentos Neurocirúrgicos , Estudos Retrospectivos , Sela Túrcica/cirurgia , Neoplasias da Base do Crânio/cirurgia , Resultado do TratamentoRESUMO
In ferromagnetic semiconductors, the coupling of magnetic ordering with semiconductor character accelerates the quantum computing. The structural stability, Curie temperature (Tc), spin polarization, half magnetic ferromagnetism and transport properties of ZnX2Se4 (X = Ti, V, Cr) chalcogenides for spintronic and thermoelectric applications are studied here by density functional theory (DFT). The highest value of Tc is perceived for ZnCr2Se4. The band structures in both spin channels confirmed half metallic ferromagnetic behavior, which is approved by integer magnetic moments (2, 3, 4) µB of Ti, V and Cr based spinels. The HM behavior is further measured by computing crystal field energy ΔEcrystal, exchange energies Δx(d), Δx (pd) and exchange constants (Noα and Noß). The thermoelectric properties are addressed in terms of electrical conductivity, thermal conductivity, Seebeck coefficient and power factor in within a temperature range 0-400 K. The positive Seebeck coefficient shows p-type character and the PF is highest for ZnTi2Se4 (1.2 × 1011 W/mK2) among studied compounds.
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There is an increasing number of patients worldwide with sleep disturbances and diabetes. Various sleep disorders, including long or short sleep duration and poor sleep quality of numerous causes, may increase the risk of diabetes. Some symptoms of diabetes, such as painful peripheral neuropathy and nocturia, or associated other sleep disorders, such as sleep breathing disorders or sleep movement disorders, may influence sleep quality and quantity. Both sleep disorders and diabetes may lead to cognitive impairment. The risk of development of cognitive impairment in diabetic patients may be related to vascular and non-vascular and other factors, such as hypoglycemia, hyperglycemia, central insulin resistance, amyloid and tau deposits and other causes. Numerous sleep disorders, e.g., sleep apnea, restless legs syndrome, insomnia, and poor sleep quality are most likely are also associated with cognitive impairment. Adequate functioning of the system of clearance of the brain from toxic substances, such as amyloid ß, i.e. glymphatic system, is related to undisturbed sleep and prevents cognitive impairment. In the case of coexistence, sleep disturbances and diabetes either independently lead to and/or mutually aggravate cognitive impairment.
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Disfunção Cognitiva , Diabetes Mellitus Tipo 2 , Transtornos do Sono-Vigília , Peptídeos beta-Amiloides , Disfunção Cognitiva/etiologia , Diabetes Mellitus Tipo 2/complicações , Humanos , Sono , Transtornos do Sono-Vigília/complicações , Transtornos do Sono-Vigília/epidemiologiaRESUMO
A number of elderly patients commit suicide due to the interaction of various factors, including, for example, feelings of loneliness, financial distress, alcohol abuse, chronic pain, progressive diseases, and personality disorders. The data from the EU countries with the highest rates of suicide and suicide attempts among people over 55 years of age warrant the consideration of new approaches to address this social problem. METHODS: PubMed and other databases, including Polish National data, were used for the analyses. RESULTS: The average European suicide-attempt rate is 18 per 100 thousand inhabitants. More cases of suicides were reported among those over 55 years of age. Suicide attempts from the year 2012 to 2014 and deaths in 2012 have been reviewed. The risk factors involved in these events, such as depression and social situations including loneliness, health condition, etc., have been discussed to suggest a plausible preventative approach for this important elderly problem. CONCLUSION: The psychophysiology of elderly persons affected by retirement, socio-economic changes, limited personal autonomy, loneliness, lack of support by the family, and diseases ultimately may lead elderly patients to commit suicide. Thus, financial freedom, family support (respect, love, and care), proper medications, psychological and psychiatric interventions may help the elderly avoid suicidal thoughts and prevent attempts.