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Abstract Human manganese superoxide dismutase (MnSOD) is a crucial oxidoreductase that maintains the vitality of mitochondria by converting superoxide (O2 ●−) to molecular oxygen (O2) and hydrogen peroxide (H2O2) with proton-coupled electron transfers (PCETs). Human MnSOD has evolved to be highly product inhibited to limit the formation of H2O2, a freely diffusible oxidant and signaling molecule. The product-inhibited complex is thought to be composed of a peroxide (O2 2−) or hydroperoxide (HO2 −) species bound to Mn ion and formed from an unknown PCET mechanism. PCET mechanisms of proteins are typically not known due to difficulties in detecting the protonation states of specific residues that coincide with the electronic state of the redox center. To shed light on the mechanism, we combine neutron diffraction and X-ray absorption spectroscopy of the product-bound, trivalent, and divalent states of the enzyme to reveal the positions of all the atoms, including hydrogen, and the electronic configuration of the metal ion. The data identifies the product-inhibited complex, and a PCET mechanism of inhibition is constructed.

ABSTRACT Purpose: This video aims to present an in-depth, step-by-step tutorial on microsurgical reconstruction for obstructive azoospermia, featuring a distinctive case involving anastomosis from vas deferens to rete testis. The primary aim of this endeavor is to offer thorough and practical insights for healthcare professionals and researchers within the realm of reproductive medicine. The video endeavors to disseminate expertise, methodologies, and perspectives that can be advantageous to individuals grappling with obstructive azoospermia, providing a significant contribution to the progress of reproductive medicine and the augmentation of existing treatment alternatives. Materials and Methods: Surgical footage was recorded using the ORBEYE 4K 3D Orbital Camera System by Olympus America, with patient consent acquired for research purposes. Additionally, a retrospective examination of patient records was undertaken to compile relevant medical histories. Results: This video furnishes an exhaustive guide to microsurgical reconstruction for obstructive azoospermia, encompassing a distinctive instance of anastomosis from vas deferens to rete testis. State-of-the-art technology, such as the ORBEYE 4K 3D Orbital Camera, heightens procedural transparency, accentuating the significance of advanced instrumentation. The ethical underpinning is emphasized by obtaining patient consent for footage utilization, and a retrospective chart review augments the repository of valuable patient data. This comprehensive approach serves as an invaluable reservoir of knowledge for medical professionals and underscores excellence in clinical and ethical healthcare research. Conclusions: Anastomosis from vas deferens to rete testis emerges as a viable surgical reconstruction alternative for obstructive azoospermia, particularly when confronted with non-dilated tubules within the epididymis.

Abstract Causing one-third of all volcanic fatalities, pyroclastic density currents create destruction far beyond our current scientific explanation. Opportunities to interrogate the mechanisms behind this hazard have long been desired, but pyroclastic density currents persistently defy internal observation. Here we show, through direct measurements of destruction-causing dynamic pressure in large-scale experiments, that pressure maxima exceed theoretical values used in hazard assessments by more than one order of magnitude. These distinct pressure excursions occur through the clustering of high-momentum particles at the peripheries of coherent turbulence structures. Particle loading modifies these eddies and generates repeated high-pressure loading impacts at the frequency of the turbulence structures. Collisions of particle clusters against stationary objects generate even higher dynamic pressures that account for up to 75% of the local flow energy. To prevent severe underestimation of damage intensities, these multiphase feedback processes must be considered in hazard models that aim to mitigate volcanic risk globally.

Abstract We formulate a Majorana mean-field theory for the extended J KΓ Kitaev model in a magnetic Zeeman field of arbitrary direction, and apply it for studying spatially inhomogeneous states harboring vortices. This mean-field theory is exact in the pure Kitaev limit and captures the essential physics throughout the Kitaev spin liquid phase. We determine the charge profile around vortices and the corresponding quadrupole tensor. The quadrupole-quadrupole interaction between distant vortices is shown to be either repulsive or attractive, depending on parameters. We predict that electrically biased scanning probe tips enable the creation of vortices at preselected positions. Our results paves the way for the electric manipulation of Ising anyons in Kitaev spin liquids.

The root maggot fly, Delia sanctijacobi (Bigot, 1885) (Diptera: Anthomyiidae), is an emerging pest of many vegetables. In this note, we report for the first time the occurrence of D. sanctijacobi damaging the tomato (Solanum lycopersicum L.) culture in Brazil. The occurrence was recorded in a tomato field located in the municipality of Coronel Freitas, Santa Catarina. The damage was characterized by roots consumption, opening of galleries in the stem and plant stand reduction. The first detection of D. sanctijacobi on tomato in Brazil brings an alert to growers and the need of future research about population dynamics and development of management strategies for this species.

Abstract Over the last decades, air pollution emissions have decreased substantially; however, inequities in air pollution persist. We evaluate county-level racial/ethnic and socioeconomic disparities in emissions changes from six air pollution source sectors (industry [SO2], energy [SO2, NOx], agriculture [NH3], commercial [NOx], residential [particulate organic carbon], and on-road transportation [NOx]) in the contiguous United States during the 40 years following the Clean Air Act (CAA) enactment (1970-2010). We calculate relative emission changes and examine the differential changes given county demographics using hierarchical nested models. The results show racial/ethnic disparities, particularly in the industry and energy generation source sectors. We also find that median family income is a driver of variation in relative emissions changes in all sectors—counties with median family income >$75 K vs. less generally experience larger relative declines in industry, energy, transportation, residential, and commercial-related emissions. Emissions from most air pollution source sectors have, on a national level, decreased following the United States CAA. In this work, we show that the relative reductions in emissions varied across racial/ethnic and socioeconomic groups.

Scientific evidence exists about the association between neurological diseases (i.e., Parkinson's disease, Alzheimer's disease, amyotrophic lateral sclerosis (ALS), multiple sclerosis, depression, and memory loss) and oxidative damage. The increasing worldwide incidence of such diseases is attracting the attention of researchers to find palliative medications to reduce the symptoms and promote quality of life, in particular, in developing countries, e.g., South America and Africa. Among potential alternatives, extracts of Cannabis Sativa L. are suitable for people who have neurological disorders, spasticity, and pain, nausea, resulting from diseases such as cancer and arthritis. In this review, we discuss the latest developments in the use of Cannabis, its subtypes and constituents, extraction methods, and relevant pharmacological effects. Biomedical applications, marketed products, and prospects for the worldwide use of Cannabis Sativa L. extracts are also discussed, providing the bibliometric maps of scientific literature published in representative countries from South America (i.e., Brazil) and Africa (i.e., South Africa). A lack of evidence on the effectiveness and safety of Cannabis, besides the concerns about addiction and other adverse events, has led many countries to act with caution before changing Cannabis-related regulations. Recent findings are expected to increase the social acceptance of Cannabis, while new technologies seem to boost the global cannabis market because the benefits of (−)-trans-delta-9-tetrahydrocannabinol (Δ9-THC) and cannabidiol (CBD) use have been proven in several studies in addition to the potential to general new employment.

ABSTRACT Considering the spectral differences between broadleaf weeds and narrow-leaf crops and the influence of terrain and soil variables on weed infestations, integrating such information into a machine-learning algorithm can lead to accurate weed maps. Therefore, we aim to evaluate the effectiveness of these variables in classifying the occurrence of broadleaf weeds in narrow-leaf crops. Weed data was collected at georeferenced points across two areas covering 200 ha (pasture) and 106 ha (sorghum), creating classes 0 (absence) and 1 (presence). For each sample point, we obtained 11 variables: soil clay content, cation exchange capacity, soil organic matter, terrain elevation, slope, NDVI, EVI, CIgreen, BGND (derived from PlanetScope images), and spatial information (X and Y coordinates). These variables were used as predictors of broadleaf weed presence and absence in the Random Forest classification algorithm. The presence and absence of broadleaf weeds were correctly classified in 84% and 74% of all predictions in the test sample sets for pasture and sorghum areas, respectively. This strategy represents an efficient way to map and manage the occurrence of broadleaf weeds in narrow-leaf crops.

ABSTRACTPseudomonas aeruginosa, a bacterium causing infections in immunocompromised individuals, regulates several of its virulence functions using three interlinked quorum sensing (QS) systems (las, rhl, and pqs). Despite its presumed importance in regulating virulence, dysfunction of the las system regulator LasR occurs frequently in strains isolated from various environments, including clinical infections. This newfound abundance of LasR-defective strains calls into question existing hypotheses regarding their selection. Indeed, current assumptions concerning factors driving the emergence of LasR-deficient isolates and the role of LasR in the QS hierarchy must be reconsidered. Here, we propose that LasR is not the primary master regulator of QS in all P. aeruginosa genetic backgrounds, even though it remains ecologically significant. We also revisit and complement current knowledge on the ecology of LasR-dependent QS in P. aeruginosa, discuss the hypotheses explaining the putative adaptive benefits of selecting against LasR function, and consider the implications of this renewed understanding.

Abstract A hallmark of cancer is a tumor cell’s ability to evade immune destruction. Somatic mutations in tumor cells that prevent immune destruction have been extensively studied. However, somatic mutations in tumor infiltrating immune (TII) cells, to our knowledge, have not been previously studied. Understandably so since normal hematopoiesis prevents the accumulation of somatic mutations in immune cells. However, clonal hematopoiesis does result in the accumulation of somatic mutations in immune cells. These mutations cannot “drive” tumor growth, however, they may “facilitate” it by inhibiting an effective anti-tumor immune response. To identify potential immunosuppressive clonal hematopoietic (CH) mutations in TII cells, we analyzed exome and RNA sequencing data from matched tumor and normal blood samples, and single-cell RNA sequencing data, from breast cancer patients. We selected mutations that were somatic, present in TII cells, clonally expanded, potentially pathogenic, expressed in TII cells, unlikely to be a passenger mutation, and in immune response associated genes. We identified eight potential immunosuppressive CH mutations in TII cells. This work is a first step towards determining if immunosuppressive CH mutations in TII cells can affect the progression of solid tumors. Subsequent experimental confirmation could represent a new paradigm in the etiology of cancer.

This paper presents a method for designing low carbon bio-based building materials, also named bio-concretes, produced with wood wastes in shavings form (WS) and cementitious pastes. As the aggregates phase of bio-concretes is composed of plant-based particles, known as porous and high water-absorbing materials, the bio-concretes cannot be designed by using the traditional design rules used for conventional mortar or concrete. Then, the method used in the current paper is an adaptation of a previous one that has been developed in a recent paper where bio-concretes were produced with a cement matrix, three types of bio-aggregates, and a proposal of a design abacus. However, when that abacus is used for designing WBC with low cement content in the matrix, the target compressive strength is not reached. In the present paper, the method is extended to low cement content matrix (up to 70% of cement substitution) and also considering the greenhouse gas (GHG) emission of the WBC. To obtain data for proposing a new design abacus, an experimental program was carried out by producing nine workable WBCs, varying wood volumetric fractions (40–45–50%), and water-to-binder ratios. The bio-concretes produced presented adequate consistency, lightness (density between 715 and 1207 kg/m3), and compressive strength ranging from 0.64 to 12.27 MPa. In addition, the GHG emissions of the WBC were analysed through the Life Cycle Assessment methodology. From the relationships obtained between density, compressive strength, water-to-binder ratio, cement consumption, and GHG emissions of the WBC, calibration constants were proposed for developing the updated and more complete abacus regarding an integrated mix design methodology.