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Phases with spontaneous time-reversal ( T ) symmetry breaking are sought after for their anomalous physical properties, low-dissipation electronic and spin responses, and information-technology applications. Recently predicted altermagnetic phase features an unconventional and attractive combination of a strong T -symmetry breaking in the electronic structure and a zero or only weak-relativistic magnetization. In this work, we experimentally observe the anomalous Hall effect, a prominent representative of the T -symmetry breaking responses, in the absence of an external magnetic field in epitaxial thin-film Mn 5 Si 3 with a vanishingly small net magnetic moment. By symmetry analysis and first-principles calculations we demonstrate that the unconventional d-wave altermagnetic phase is consistent with the experimental structural and magnetic characterization of the Mn 5 Si 3 epilayers, and that the theoretical anomalous Hall conductivity generated by the phase is sizable, in agreement with experiment. An analogy with unconventional d-wave superconductivity suggests that our identification of a candidate of unconventional d-wave altermagnetism points towards a new chapter of research and applications of magnetic phases. The classification of magnets now includes altermagnets which possess opposite-spin sublattices connected by rotation and share some features with ferro- and antiferromagnets. Here the authors report the anomalous Hall effect in Mn5Si3 and interpret the results in terms of a d-wave altermagnetic phase.

Population growth and urbanization have led to critical environmental challenges worldwide. Chemical pollutants, especially Potentially Toxic Elements (PTEs) such as Cd (Cadmium), Cu (Copper), Zn (Zinc), Al (Aluminum) and Mn (Manganese), as well as macroelements like P (Phosphorus), affect physicochemical and ecological parameters, posing risks to both human health and biodiversity. This study evaluates the influence of seasonality on the concentration of these PTEs in the waters of the Negro River, Manaus, Amazonas. Sampling was conducted at 60 sites along the river in January 2023, September 2023, and March 2024. Sampling, storage, and analyses followed the procedures established in the Standard Methods for the Examination of Water and Wastewater . Results revealed elevated mean Al and P concentrations (above 1250 µg/L and 250 µg/L, respectively), suggesting significant inputs of organic matter and surface urban pollution. Principal Component Analysis (PCA) revealed distinct patterns in January, higher levels of Na, Mg, Ca, Al, P, Ti, Be, and Cu; in September, predominance of K, Rb, and Ba; and in March, Li and Fe. Contamination by PTEs is multifactorial: although seasonality is a key driver, other factors, such as urbanization, proximity to agricultural areas, and industrial discharges, strongly modulate water quality.

The widely used methodology to quantify polyphenols—the Folin-Ciocalteu (FC) method—cannot be applied indiscriminately since different matrices may impair the assay’s accuracy. Thus, this study aimed to adapt the FC method for the açaí seed extract, a tannin-rich extract with potential applications for various therapies. Firstly, a pre-method standardization was established to determine parameters such as reading wavelength (765 nm), reaction time (30 min), and the reference substance (pyrogallol). In the validation step, the adapted method responded linearly to the analyte (R2 = 0.9910), ensuring its selectivity (linearity and selectivity curves statistically parallel) and accuracy (99.18–101.43%). Furthermore, the method proved to be precise (RSD ≤ 2.63%) at the two levels assessed (repeatability and intermediate precision) and robust (RSD ≤ 4.45%) concerning variation on the Na2CO3 concentration and the reaction time. The limits of detection and quantification were also calculated (9.9 µg/mL and 33.1 µg/mL, respectively). An additional step for tannins quantification based on its reported selective precipitation by complexing agents was also evaluated; however, unspecific precipitation was observed, reducing the results’ accuracy. Our work successfully adapted and validated a method for total phenolics quantification of açaí seed extract, resulting in 38 g of pyrogallol equivalent/100 g of extract. Graphic abstract

Skyrmions are topologically protected non-collinear magnetic structures. Their stability is ideally suited to carry information in, e.g., racetrack memories. The success of such a memory critically depends on the ability to stabilize and manipulate skyrmions at low magnetic fields. The non-collinear Dzyaloshinskii-Moriya interaction originating from spin-orbit coupling drives skyrmion formation. It competes with Heisenberg exchange and magnetic anisotropy favoring collinear states. Isolated skyrmions in ultra-thin films so far required magnetic fields as high as several Tesla. Here, we show that isolated skyrmions in a monolayer of Co/Ru(0001) can be stabilized down to vanishing fields. Even with the weak spin-orbit coupling of the 4d element Ru, homochiral spin spirals and isolated skyrmions were detected with spin-sensitive scanning tunneling microscopy. Density functional theory calculations explain the stability of the chiral magnetic features by the absence of magnetic anisotropy energy. Skyrmions are promising for spintronics but usually require large spin-orbit coupling of 5d-metals and external magnetic field. Here the authors realize stabilization of isolated skyrmions at a 4d-metal interface of weak chiral interaction and magnetic anisotropy down to vanishing field.

Why do firms pay different wages? Empirical evidence suggests the presence of substantial differences in firm pay controlling for worker skill. Moreover, these differences are uncorrelated with skills, indicating the absence of sorting. I show that the face value interpretation is inconsistent with evidence on coworker segregation. I interpret the evidence by applying a sorting model and show that the correlation is biased. I identify nonmonotonicities in wages as the reason for this bias and show that a measure of worker-coworker sorting is more accurate. By calibrating the model to US data, I confirm that the model matches many job market characteristics.

Enzymes are biocatalysts that are widely used in different industries and generate billions of dollars annually. With the advancement of biotechnology, new enzymatic sources are being evaluated, especially microbial ones, in order to find efficient producers. Endophytic fungi are promising sources of biomolecules; however, Amazonian species are still poorly studied as to their enzymatic production potential. In this sense, the production of hydrolases (amylases, lipases, cellulases and pectinases) was evaluated in endophytic fungi isolated from the leaves, roots and stems of açai palms (Euterpe precatoria). A qualitative test was carried out to detect the enzymatic synthesis in each isolate, and the most promising ones were cultivated using submerged fermentation. The enzyme extracts were quantified to determine those with the greatest activity. Cellulolytic and amylolytic extracts showed the highest enzymatic activities and were partially characterized. Among 50 isolates, 82.9% produced pectinase, 58.5% produced cellulase, 31.7% produced amylase, and 12.2% produced lipase. Penicillium sp. L3 was the best producer of amylase and Colletotrichum sp. S1 was the best producer of cellulase in liquid medium cultivation. The amylolytic extract showed the highest enzymatic activity at pH 8.0 and 45 °C, and the cellulolytic extract at pH 5.0 and 35 °C. The cellulase and amylase produced by the endophytes had their molecular masses estimated between 38 and 76 kDa. These results indicate that endophytic fungi from the açai palm can be used as a new source of hydrolytic enzymes, which can be applied in numerous biotechnological processes.

Stem cells therapies are a promising therapeutic option, and although not yet widely used in daily clinical practice in companion animals, they have shown great potential in the treatment of a variety of diseases. This study aims to investigate the individual profile of Portuguese veterinary practitioners, their knowledge about this type of therapy and their interest in its future use and application. This questionnaire-based descriptive study was carried out in Portugal from November 2021 to January 2022. A questionnaire-based survey was conducted online, using an electronic platform. The following topics were surveyed: (i) profile of veterinarians; (ii) knowledge about cell therapies; and (iii) interest in future use and application. After an internal validation, the survey was released online for three months in Portuguese veterinary social network groups. Data were collected and descriptive analysis and Chi-square test were performed. A total of 275 responses were obtained and analysed. Analysis of the results showed that the participating veterinarians know what mesenchymal stromal cells (MSCs) are (90.9%) and are generally aware of their therapeutic potential (94.5%). Regarding their use, 56.7% of the respondents do not know their application in veterinary pathologies. The remaining 43.3% indicated the situations in which they knew of its use. Orthopaedic and dental or oral diseases were the most frequently mentioned. Regarding the immunological effect of MSCs, there is a great lack of information. Data analysis showed that 72.4% of respondents were unaware of the possibility of an immunogenic response following their administration. However, 53.5% stated that they were aware of the positive immunomodulatory capacity. Most professionals who participated in this survey consider this topic relevant in veterinary medicine (95.6%), as well as the existence of this type of service in the national territory (96.4%). The great interest shown by 96.7% of the respondents in learning more about the subject highlights the importance of raising awareness, conducting further studies and promoting knowledge sharing in their daily clinical practice and research. The relationship between the national status of stem-cell therapy and veterinarians’ knowledge is influenced by limited regulation but growing professional interest and driven by private companies and professional organisations. This study contributes to a better understanding of the trends related to this topic in the context of veterinary practice in Portugal.

Stem cells therapies are a promising therapeutic option, and although not yet widely used in daily clinical practice in companion animals, they have shown great potential in the treatment of a variety of diseases. This study aims to investigate the individual profile of Portuguese veterinary practitioners, their knowledge about this type of therapy and their interest in its future use and application. This questionnaire-based descriptive study was carried out in Portugal from November 2021 to January 2022. A questionnaire-based survey was conducted online, using an electronic platform. The following topics were surveyed: (i) profile of veterinarians; (ii) knowledge about cell therapies; and (iii) interest in future use and application. After an internal validation, the survey was released online for three months in Portuguese veterinary social network groups. Data were collected and descriptive analysis and Chi-square test were performed. A total of 275 responses were obtained and analysed. Analysis of the results showed that the participating veterinarians know what mesenchymal stromal cells (MSCs) are (90.9%) and are generally aware of their therapeutic potential (94.5%). Regarding their use, 56.7% of the respondents do not know their application in veterinary pathologies. The remaining 43.3% indicated the situations in which they knew of its use. Orthopaedic and dental or oral diseases were the most frequently mentioned. Regarding the immunological effect of MSCs, there is a great lack of information. Data analysis showed that 72.4% of respondents were unaware of the possibility of an immunogenic response following their administration. However, 53.5% stated that they were aware of the positive immunomodulatory capacity. Most professionals who participated in this survey consider this topic relevant in veterinary medicine (95.6%), as well as the existence of this type of service in the national territory (96.4%). The great interest shown by 96.7% of the respondents in learning more about the subject highlights the importance of raising awareness, conducting further studies and promoting knowledge sharing in their daily clinical practice and research. The relationship between the national status of stem-cell therapy and veterinarians' knowledge is influenced by limited regulation but growing professional interest and driven by private companies and professional organisations. This study contributes to a better understanding of the trends related to this topic in the context of veterinary practice in Portugal.

A hypoxic microenvironment promotes the aggressiveness of lung adenocarcinoma (LUAD) through treatment resistance and generation of new lymphatic vessels (i.e., lymphangiogenesis) favoring metastatic dissemination. Transcriptomic analysis of cohorts of LUAD patients highlighted LINC01116, a long noncoding RNA, associated with a bad prognosis, a high rate of recurrence, and induced by hypoxia in tumors. Gain‐ (overexpression) and loss‐of‐function (CRISPRi (Clustered Regularly Interspaced Short Palindromic Repeats interference, RNA interference)) approaches performed in LUAD cancer cell lines did not reveal a clear regulatory role for LINC01116 in tumor cells. Analyses of LUAD single‐cell RNA sequencing data sets and RNA Fluorescent In Situ Hybridization (RNA‐FISH) showed high expression of LINC01116 in lymphatic endothelial cells (LEC) pointing to this transcript as a specific biomarker of tumoral lymphangiogenesis. Efficient knockdown of LINC01116 in LEC in normoxic or hypoxic conditions impacted the proliferation rate under hypoxic stimulation and revealed a gene signature associated with proliferation and hypoxia sensing. Together, our data suggest a role for LINC01116 in pathological lymphangiogenesis of lung tumors. The LINC01116 long noncoding RNA is induced by hypoxia and associated with poor prognosis and high recurrence rates in two cohorts of lung adenocarcinoma patients. Here, we demonstrate that besides its expression in cancer cells, LINC01116 is markedly expressed in lymphatic endothelial cells of the tumor stroma in which it participates in hypoxia‐sensing and cell proliferation control in lymphangiogenesis.

We propose an algorithm for estimating the ionospheric scintillation phase on global navigation satellite systems (GNSS) receivers for scintillation monitoring. The algorithm comprises linear time-invariant filtering of available observables or easily derived in traditional or Kalman filter-based carrier tracking loop structures, exploiting their complementary frequency content to provide real-time scintillation phase estimates for monitoring purposes. This algorithm is developed for receivers with traditional and Kalman frequency locked loops, but can be adapted to receivers with traditional and Kalman phase locked loops. The performance of the algorithm is evaluated via simulations with synthetic severe scintillation data, showing its capability to provide the scintillation phase estimates. In addition, we evaluated the algorithm with real data presenting equatorial scintillation collected by a professional GNSS receiver, where the scintillation phase standard deviation computed from the estimates provided by the real-time algorithm is compared to the standard deviation derived by post-processing, showing good agreement.