Moving Dirac nodes by chemical substitution.

Dirac fermions play a central role in the study of topological phases, for they can generate a variety of exotic states, such as Weyl semimetals and topological insulators. The control and manipulation of Dirac fermions constitute a fundamental step toward the realization of novel concepts of electronic devices and quantum computation. By means of Angle-Resolved Photo-Emission Spectroscopy (ARPES) experiments and ab initio simulations, here, we show that Dirac states can be effectively tuned by doping a transition metal sulfide, [Formula: see text], through Co/Ni substitution. The symmetry and chemical characteristics of this material, combined with the modification of the charge-transfer gap of [Formula: see text] across its phase diagram, lead to the formation of Dirac lines, whose position in k-space can be displaced along the [Formula: see text] symmetry direction and their form reshaped. Not only does the doping x tailor the location and shape of the Dirac bands, but it also controls the metal-insulator transition in the same compound, making [Formula: see text] a model system to functionalize Dirac materials by varying the strength of electron correlations.

Charge Transfer and Orbital Reconstruction at an Organic-Oxide Interface.

The two-dimensional electron system (2DES) located at the surface of strontium titanate (STO) and at several other STO-based interfaces has been an established platform for the study of novel physical phenomena since its discovery. Here we report how the interfacing of STO and tetracyanoquinodimethane (TCNQ) results in a charge transfer that depletes the number of free carriers at the STO surface, with a strong impact on its electronic structure. Our study paves the way for efficient tuning of the electronic properties, which promises novel applications in the framework of oxide/organic-based electronics.

Strain engineering of the charge and spin-orbital interactions in Sr2IrO4.

In the high spin-orbit-coupled Sr2IrO4, the high sensitivity of the ground state to the details of the local lattice structure shows a large potential for the manipulation of the functional properties by inducing local lattice distortions. We use epitaxial strain to modify the Ir-O bond geometry in Sr2IrO4 and perform momentum-dependent resonant inelastic X-ray scattering (RIXS) at the metal and at the ligand sites to unveil the response of the low-energy elementary excitations. We observe that the pseudospin-wave dispersion for tensile-strained Sr2IrO4 films displays large softening along the [h,0] direction, while along the [h,h] direction it shows hardening. This evolution reveals a renormalization of the magnetic interactions caused by a strain-driven cross-over from anisotropic to isotropic interactions between the magnetic moments. Moreover, we detect dispersive electron-hole pair excitations which shift to lower (higher) energies upon compressive (tensile) strain, manifesting a reduction (increase) in the size of the charge gap. This behavior shows an intimate coupling between charge excitations and lattice distortions in Sr2IrO4, originating from the modified hopping elements between the t2g orbitals. Our work highlights the central role played by the lattice degrees of freedom in determining both the pseudospin and charge excitations of Sr2IrO4 and provides valuable information toward the control of the ground state of complex oxides in the presence of high spin-orbit coupling.

Triple-Point Fermions in Ferroelectric GeTe.

Ferroelectric α-GeTe is unveiled to exhibit an intriguing multiple nontrivial topology of the electronic band structure due to the existence of triple-point and type-II Weyl fermions, which goes well beyond the giant Rashba spin splitting controlled by external fields as previously reported. Using spin- and angle-resolved photoemission spectroscopy combined with ab initio density functional theory, the unique spin texture around the triple point caused by the crossing of one spin-degenerate and two spin-split bands along the ferroelectric crystal axis is derived. This consistently reveals spin winding numbers that are coupled with time-reversal symmetry and Lorentz invariance, which are found to be equal for both triple-point pairs in the Brillouin zone. The rich manifold of effects opens up promising perspectives for studying nontrivial phenomena and multicomponent fermions in condensed matter systems.

LEGO MINDSTORMS Fraction Collector: A Low-Cost Tool for a Preparative High-Performance Liquid Chromatography System.

Preparative high-performance liquid chromatographic (prep-HPLC) systems are used in many research schemes including purifying products from reaction mixtures, fractionating natural product extracts, and isolating compounds. Manual fraction collection from a prep-HPLC is a common method; however, it often lacks the reproducibility of automated fraction collectors due to human error. Automated fraction collectors for prep-HPLC systems can add thousands of dollars to the cost of prep-HPLC and are thus not always available to budgetary constrained research programs. Nevertheless, an automated fraction collector is a tremendous resource for any lab that employs prep-HPLC methods. Using LEGO MINDSTORMS pieces and easily obtained lumber and a steel C-channel, we were able to deploy an automated fraction collector for only a fraction of the cost of a commercial instrument. The programming software allows for a simple interface to create fraction collection programs tailored to individual HPLC methods. This fraction collector can be connected to any LC system and tailored to collect fractions in nearly any size or shaped container. This fraction collector was designed to provide maximum versatility and will make automated fraction collection more accessible to all researchers. The simple interface allows for quickly adapting the fraction collector method to any liquid chromatographic separation, no matter how complex.

Manipulating the Topological Interface by Molecular Adsorbates: Adsorption of Co-Phthalocyanine on Bi2Se3.

Topological insulators are a promising class of materials for applications in the field of spintronics. New perspectives in this field can arise from interfacing metal-organic molecules with the topological insulator spin-momentum locked surface states, which can be perturbed enhancing or suppressing spintronics-relevant properties such as spin coherence. Here we show results from an angle-resolved photemission spectroscopy (ARPES) and scanning tunnelling microscopy (STM) study of the prototypical cobalt phthalocyanine (CoPc)/Bi2Se3 interface. We demonstrate that that the hybrid interface can act on the topological protection of the surface and bury the Dirac cone below the first quintuple layer.

Water Formation for the Metalation of Porphyrin Molecules on Oxidized Cu(111).

Herein the formation of water molecules in the intermediate step of the redox reaction of porphyrins self-metalation on O/Cu(111) is demonstrated. Photoemission measurements show that the temperature on which porphyrins pick-up a substrate metal atom on O/Cu(111) is reduced by about 185±15 K with respect to the pure Cu(111). DFT calculations clearly indicate that the formation of a water molecule is less expensive than the formation of H2 on the O/Cu(111) substrate and, in some cases, it can be also exothermic.

A pharmacoeconomic analysis from Italian guidelines for the management of prolactinomas.

Background: Prolactinoma, the most common pituitary adenoma, is usually treated with dopamine agonist (DA) therapy like cabergoline. Surgery is second-line therapy, and radiotherapy is used if surgical treatment fails or in relapsing macroprolactinoma. Objective: This study aimed to provide economic evidence for the management of prolactinoma in Italy, using a cost-of-illness and cost-utility analysis that considered various treatment options, including cabergoline, bromocriptine, temozolomide, radiation therapy, and surgical strategies. Methods: The researchers conducted a systematic literature review for each research question on scientific databases and surveyed a panel of experts for each therapeutic procedure's specific drivers that contributed to its total cost. Results: The average cost of the first year of treatment was €2,558.91 and €3,287.40 for subjects with microprolactinoma and macroprolactinoma, respectively. Follow-up costs from the second to the fifth year after initial treatment were €798.13 and €1,084.59 per year in both groups. Cabergoline had an adequate cost-utility profile, with an incremental cost-effectiveness ratio (ICER) of €3,201.15 compared to bromocriptine, based on a willingness-to-pay of €40,000 per quality-adjusted life year (QALY) in the reference economy. Endoscopic surgery was more cost-effective than cabergoline, with an ICER of €44,846.64. Considering a willingness-to-pay of €40,000/QALY, the baseline findings show cabergoline to have high cost utility and endoscopic surgery just a tad above that. Conclusions: Due to the favorable cost-utility profile and safety of surgical treatment, pituitary surgery should be considered more frequently as the initial therapeutic approach. This management choice could lead to better outcomes and an appropriate allocation of healthcare resources.

Weyl spin-momentum locking in a chiral topological semimetal.

Spin-orbit coupling in noncentrosymmetric crystals leads to spin-momentum locking - a directional relationship between an electron's spin angular momentum and its linear momentum. Isotropic orthogonal Rashba spin-momentum locking has been studied for decades, while its counterpart, isotropic parallel Weyl spin-momentum locking has remained elusive in experiments. Theory predicts that Weyl spin-momentum locking can only be realized in structurally chiral cubic crystals in the vicinity of Kramers-Weyl or multifold fermions. Here, we use spin- and angle-resolved photoemission spectroscopy to evidence Weyl spin-momentum locking of multifold fermions in the chiral topological semimetal PtGa. We find that the electron spin of the Fermi arc surface states is orthogonal to their Fermi surface contour for momenta close to the projection of the bulk multifold fermion at the Γ point, which is consistent with Weyl spin-momentum locking of the latter. The direct measurement of the bulk spin texture of the multifold fermion at the R point also displays Weyl spin-momentum locking. The discovery of Weyl spin-momentum locking may lead to energy-efficient memory devices and Josephson diodes based on chiral topological semimetals.

Botanical inhibitors of SARS-CoV-2 viral entry: a phylogenetic perspective.

Throughout the SARS-CoV-2 pandemic, the use of botanical dietary supplements in the United States has increased, yet their safety and efficacy against COVID-19 remains underexplored. The Quave Natural Product Library is a phylogenetically diverse collection of botanical and fungal natural product extracts including popular supplement ingredients. Evaluation of 1867 extracts and 18 compounds for virus spike protein binding to host cell ACE2 receptors in a SARS-CoV-2 pseudotyped virus system identified 310 extracts derived from 188 species across 76 families (3 fungi, 73 plants) that exhibited ≥ 50% viral entry inhibition activity at 20 µg/mL. Extracts exhibiting mammalian cytotoxicity > 15% and those containing cardiotoxic cardiac glycosides were eliminated. Three extracts were selected for further testing against four pseudotyped variants and infectious SARS-CoV-2 and were then further chemically characterized, revealing the potent (EC50 < 5 µg/mL) antiviral activity of Solidago altissima L. (Asteraceae) flowers and Pteridium aquilinum (L.) Kuhn (Dennstaedtiaceae) rhizomes.

Italian Guidelines for the Management of Prolactinomas.

INTRODUCTION: This guideline (GL) is aimed at providing a reference for the management of prolactin (PRL)-secreting pituitary adenoma in adults. However, pregnancy is not considered. METHODS: This GL has been developed following the methods described in the Manual of the Italian National Guideline System. For each question, the panel appointed by Associazione Medici Endocrinologi (AME) has identified potentially relevant outcomes, which have then been rated for their impact on therapeutic choices. Only outcomes classified as "critical" and "important" have been considered in the systematic review of evidence and only those classified as "critical" have been considered in the formulation of recommendations. RESULTS: The present GL provides recommendations regarding the role of pharmacological and neurosurgical treatment in the management of prolactinomas. We recommend cabergoline (Cab) vs. bromocriptine (Br) as the firstchoice pharmacological treatment to be employed at the minimal effective dose capable of achieving the regression of the clinical picture. We suggest that medication and surgery are offered as suitable alternative first-line treatments to patients with non-invasive PRL-secreting adenoma, regardless of size. We suggest Br as an alternative drug in patients who are intolerant to Cab and are not candidates for surgery. We recommend pituitary tumor resection in patients 1) without any significant neuro-ophthalmologic improvement within two weeks from the start of Cab, 2) who are resistant or do not tolerate Cab or other dopamine-agonist drugs (DA), 3) who escape from previous efficacy of DA, and 4) who are unwilling to undergo a chronic DA treatment. We recommend that patients with progressive disease notwithstanding previous tumor resection and ongoing DA should be managed by a multidisciplinary team with specific expertise in pituitary diseases using a multimodal approach that includes repeated surgery, radiotherapy, DA, and possibly, the use of temozolomide. CONCLUSION: The present GL is directed to endocrinologists, neurosurgeons, and gynecologists working in hospitals, in territorial services or private practice, and to general practitioners and patients.

Infectious complications after surgery for perihilar cholangiocarcinoma: A single Western center experience.

BACKGROUND: The aim of this study was to analyze the risk factors for surgical infectious complications and the outcomes of patients undergoing surgery for perihilar cholangiocarcinoma according to the microbiological examinations. METHODS: Patients who underwent surgery for perihilar cholangiocarcinoma in the last decade were enrolled, and all clinical and microbiological data were collected from a retrospective monocentric database. Univariate and multivariate analyses were performed distinguishing patients who developed at least 1 surgical infectious complication (surgical site infections, acute bacterial cholangitis, bacteremia). RESULTS: A total of 98 patients were included. Among patients who developed surgical infectious complications (51%), many preoperative characteristics were significantly more frequent: American Society of Anesthesiologists score ≥3 (P = .026), neutrophil-to-lymphocyte ratio ≥3.4 (P = .001), endoscopic sphincterotomy (P = .032), ≥2 biliary drainage procedures (P = .013), acute cholangitis (P = .012), multidrug resistant (P = .009), and ≥3 microorganisms' detection (P = .042); whereas during the postoperative period, surgical infectious complications were associated to increased incidence of intensive care unit readmission (P = .031), major complications (P < .001), posthepatectomy liver failure (P = .005), ascites (P = .008), biliary leakage (P = .008), 90-day readmission (P = .003), and prolonged length of hospital stay (P < .001). At the multivariate analysis 3 independent preoperative risk factors for surgical infectious complications were identified: neutrophil-to-lymphocyte ratio ≥3.4 (P = .004), endoscopic sphincterotomy (P = .009), and acute cholangitis (P = .013). The presence of multidrug-resistance in the perioperative biliary cultures was related to postoperative multidrug-resistant species from all cultures (P < .001) and organ/space and incisional-surgical site infections (P ≤ .044). CONCLUSION: Infective complications after surgery for perihilar cholangiocarcinoma worsen the short-term outcomes. A careful microbiological surveillance should be carried out in all cases to prevent and promptly treat surgical infectious complications.

Italian Association of Clinical Endocrinologists (AME) and International Chapter of Clinical Endocrinology (ICCE). Position statement for clinical practice: prolactin-secreting tumors.

Prolactinomas are the most frequent pituitary adenomas. Prolactinoma may occur in different clinical settings and always require an individually tailored approach. This is the reason why a panel of Italian neuroendocrine experts was charged with the task to provide indications for the diagnostic and therapeutic approaches that can be easily applied in different contexts. The document provides 15 recommendations for diagnosis and 54 recommendations for treatment, issued according to the GRADE system. The level of agreement among panel members was formally evaluated by RAND-UCLA methodology. In the last century, prolactinomas represented the paradigm of pituitary tumors for which the development of highly effective drugs obtained the best results, allowing to avoid neurosurgery in most cases. The impressive improvement of neurosurgical endoscopic techniques allows a far better definition of the tumoral tissue during surgery and the remission of endocrine symptoms in many patients with pituitary tumors. Consequently, this refinement of neurosurgery is changing the therapeutic strategy in prolactinomas, allowing the definitive cure of some patients with permanent discontinuation of medical therapy.

A risk-analysis approach to the evaluation of analytical quality.

BACKGROUND: Setting specifications for analytical quality is always difficult. The risk-management approach might be a way to do so. In this approach, the definition of the required analytical quality is based on the evaluation of patient risk. Risk derives from the probability of error and from the damage that such an error might cause. METHODS: Eight Italian laboratories took part in this experiment. Measurements of glucose and total calcium were taken as examples. Analytical quality was evaluated using a specific ring trial with a frozen serum pool and by means of internal quality-control data. The total allowable error was defined according to biological variation specifications. The probability of error was extracted from the imprecision and comparative bias data of each laboratory. The damage caused by a wrong result was evaluated using the absolute probability judgment approach. RESULTS: According to the iso-risk plots (standardized hyperboles on a graph where the x-axis represents damage and the y-axis represents probability) for glucose, all the laboratories were working with an analytical quality that guaranteed low risk for patients. On the contrary, for total calcium none of the laboratories exhibited sufficient quality to guarantee low risk for patients, the presence of bias being the most relevant problem. CONCLUSIONS: The results seem to demonstrate the applicability of the risk approach to the analytical phase, indicating a new possible way to define analytical quality targets.

Ethnobotany of the Aegadian Islands: safeguarding biocultural refugia in the Mediterranean.

BACKGROUND: The Aegadian Islands are located west of Trapani, Sicily. Once the site of bountiful tuna fisheries and fruit orchards (plums, peaches, apricots), grapevines, prickly pears, and grains, the local economy is now based on tourism, and many traditional agricultural and maritime practices have been abandoned. In this study, we aimed to evaluate the state of traditional ecological knowledge (TEK) concerning the use of wild and cultivated plants and fungi for human health, food, maritime, and agricultural purposes on the islands of Levanzo, Favignana, and Marettimo and compare present-day practices with those documented in the past. METHODS: In-depth semi-structured interviews were conducted in Italian with 48 participants with prior informed consent from May 2016 to July 2017 and October 2018. Herbarium voucher specimens of wild species were collected for herbarium deposit. A rigorous literature review of scientific and other local reports on TEK of wild flora and their application in food, health, and household applications was undertaken for the purpose of comparing findings from this field study with prior reports. RESULTS: A total of 122 plant and five fungal taxa representing 54 families were cited for 355 uses. Among the most pervasive species in the landscape, Agave americana and A. sisalana had diverse applications in the past, which ranged from cordage for agricultural and maritime applications to tools for sewing, eating land snails, and constructing furniture. Fields of Ferula communis also dominate the landscape, and the dry stems were used extensively in furniture making; this species also serves as an environmental indicator for the location of the most preferred edible mushrooms, Pleurotus eryngii var. ferulae. Other important flora included topical medicinal applications of Glaucium flavum for hematomas and Artemisia arborescens for ritual bathing of newborns. CONCLUSION: While many plant-based traditions have disappeared from daily practice, especially those related to traditional fishing and health practices, they remain in the memories of the eldest subset of the population. Documenting this knowledge before it disappears from oral history is a key factor in reducing loss of TEK and biocultural diversity, safeguarding the role of the Aegadian Islands as biocultural refugia.

Universal Structural Influence on the 2D Electron Gas at SrTiO3 Surfaces.

The 2-dimensional electron gas (2DEG) found at the surface of SrTiO3 and related interfaces has attracted significant attention as a promising basis for oxide electronics. In order to utilize its full potential, the response of this 2DEG to structural changes and surface modification must be understood in detail. Here, a study of the detailed electronic structure evolution of the 2DEG as a function of sample temperature and surface step density is presented. By comparing the experimental results with ab initio calculations, it is shown that local structure relaxations cause a metal-insulator transition of the system around 135 K. This study presents a new and simple way of tuning the 2DEG via surface vicinality and identifies how the operation of prospective devices will respond to changes in temperature.

Band Structure Extraction at Hybrid Narrow-Gap Semiconductor-Metal Interfaces.

The design of epitaxial semiconductor-superconductor and semiconductor-metal quantum devices requires a detailed understanding of the interfacial electronic band structure. However, the band alignment of buried interfaces is difficult to predict theoretically and to measure experimentally. This work presents a procedure that allows to reliably determine critical parameters for engineering quantum devices; band offset, band bending profile, and number of occupied quantum well subbands of interfacial accumulation layers at semiconductor-metal interfaces. Soft X-ray angle-resolved photoemission is used to directly measure the quantum well states as well as valence bands and core levels for the InAs(100)/Al interface, an important platform for Majorana-zero-mode based topological qubits, and demonstrate that the fabrication process strongly influences the band offset, which in turn controls the topological phase diagrams. Since the method is transferable to other narrow gap semiconductors, it can be used more generally for engineering semiconductor-metal and semiconductor-superconductor interfaces in gate-tunable superconducting devices.

Proximity-Induced Novel Ferromagnetism Accompanied with Resolute Metallicity in NdNiO3 Heterostructure.

Employing X-ray magnetic circular dichroism (XMCD), angle-resolved photoemission spectroscopy (ARPES), and momentum-resolved density fluctuation (MRDF) theory, the magnetic and electronic properties of ultrathin NdNiO3 (NNO) film in proximity to ferromagnetic (FM) La0.67 Sr0.33 MnO3 (LSMO) layer are investigated. The experimental data shows the direct magnetic coupling between the nickelate film and the manganite layer which causes an unusual ferromagnetic (FM) phase in NNO. Moreover, it is shown the metal-insulator transition in the NNO layer, identified by an abrupt suppression of ARPES spectral weight near the Fermi level (EF ), is absent. This observation suggests that the insulating AFM ground state is quenched in proximity to the FM layer. Combining the experimental data (XMCD and AREPS) with the momentum-resolved density fluctuation calculation (MRDF) reveals a direct link between the MIT and the magnetic orders in NNO systems. This work demonstrates that the proximity layer order can be broadly used to modify physical properties and enrich the phase diagram of RENiO3 (RE = rare-earth element).

PATHFAST NT-proBNP (N-terminal-pro B type natriuretic peptide): a multicenter evaluation of a new point-of-care assay.

BACKGROUND: The biochemical determination of cardiac natriuretic peptides, primarily brain natriuretic peptide (BNP) and the amino-terminal fragment of its pro-hormone proBNP (NT-proBNP), are reliable tools for diagnosing cardiac disease, establishing prognosis and evaluating the effectiveness of treatment. These biomarkers have proven to be of particular value in the management of chronic and acute heart failure patients, and in the outpatient and the emergency setting. METHODS: A multicenter evaluation was performed to assess the practicability, and the analytical and clinical performance of a new point-of-care testing (POCT) PATHFAST NT-proBNP assay. This is an immunochemiluminescent assay using two polyclonal antibodies in a sandwich test format, and performed with a PATHFAST automated analyzer. RESULTS: The limit of detection (mean+3 SD of the signal of 20 replicates of the zero calibrator obtained in one run) was 0.535 ng/L. An imprecision study, performed in accordance with the CLSI protocol, showed coefficients of variation of 4.0%-6.4% (within-run imprecision), 0.0%-3.4% (between-run imprecision), 5.5%-7.2% (between-day imprecision), 7.6%-8.9% (total imprecision). The method was linear to 28,755 ng/L. Slopes and intercepts ranged from 0.89 to 0.90 and from 10.96 to 22.85, respectively when lithium-heparin plasma samples (n=100) were used to compare the assay under evaluation with the routine laboratory methods (Dimension RxL, Stratus CS). When testing matched samples (n=52), a significant difference was found between the 50th percentile NT-proBNP concentration in K(2)EDTA whole blood, K(2)EDTA plasma, lithium-heparin plasma and serum. No significant interference was observed for NT-proBNP in lipemic (tryglicerides up to 28.54 mmol/L), icteric (total and conjugated bilirubin up to 513 and 13 micromol/L, respectively) or hemolyzed (hemoglobin up to 13.50 g/L) samples. The NT-proBNP concentration in a group of 180 healthy donors was significantly influenced by age and gender. In a selected population of patients (n=56) with acute dyspnea admitted to the emergency department, a marked reduction in cardiac natriuretic peptide concentrations was observed in hospitalized patients suffering from heart failure who had a better prognosis compared with those with a poorer prognosis (NT-proBNP mean Delta change, % from -22 to -71 vs. +9 to -11). CONCLUSIONS: The satisfactory analytical and clinical performance of the PATHFAST NT-proBNP assay, together with its excellent practicability, suggests that it would be a reliable tool in clinical practice, in the emergency setting for point-of-care testing, as well as in the central laboratory.

Evaluation of analytical performance of the Pathfast cardiac troponin I.

BACKGROUND: Cardiac troponins are considered the cornerstone for risk stratification and diagnosis of patients with acute coronary syndrome (ACS). Following Clinical Laboratory Standards Institute (CLSI) guidelines, we assessed the analytical performances of the Pathfast (Mitsubishi, Japan) cTnI method. METHODS: We evaluated different sample types. Control materials and lithium heparin plasma pools were used to determine: limit of blank (LoB), limit of detection (LoD), imprecision and linearity. The effects of potential endogenous interfering substances and the possibility of falsely increased cardiac troponin I (cTnI) concentrations attributable to the presence of heterophilic antibodies (HA), rheumatoid factor (RF) and human anti-mouse antibodies (HAMA) in high concentrations were evaluated. The 99th percentile limit of the cTnI value distribution was determined from 320 Caucasian reference individuals. RESULTS: No significant differences were found when cTnI concentrations of 40 lithium-heparin plasma samples were compared with the matched values of K(2)-EDTA plasma, whole blood and serum samples. The LoB and the LoD of the cTnI method were 0.0048 and 0.0066 microg/L, respectively. cTnI mean values from 0.66 to 6.0 microg/L showed a total CV% from 6.0 to 6.4. cTnI at a concentration of 0.02 microg/L was associated with a total CV of 9.6%. The method gave a linear response for cTnI concentrations within the measurement range. In six of 12 samples containing HA, a positive interference was demonstrated. The 99th percentile limit of the cTnI distribution in the reference population was 0.013 microg/L. CONCLUSIONS: The data indicate that the cTnI Pathfast method may be suitable for helping clinicians in the management of patients with ACS.