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Buffering Acid Mine Drainage (AMD) is an essential part of the remediation procedures aimed to reduce the environmental impact of high-sulfur waste and tailing dumps. As solubility of most of the heavy metals dramatically decreases at increasing pH, buffering also results in a strong reduction of potentially toxic elements load of waters.Adding carbonate-based materials, like lime, can neutralize acid mine drainage by raising pH of water and triggering precipitation of metals as hydroxides (Grieco et al., 2021), but the treatment processes are often expensive in terms of capital and operating costs. The use of mining waste as buffering agent, on the other hand, could positively contribute to a circular economy strategy for the secondary recovery of metals from abandoned mine wastes and tailings. The addition of the buffering agent to reworked tailings can result in secondary dumps with highly reduced or even absent acid mine drainage potential.The aim of the present research is to evaluate the buffering potential and the leaching waters heavy metal load reduction of feldspar mining wastes and the effect of doping it with a minor fraction of carbonate-rich limestone quarrying wastes. The frame of the research is the evaluation of potential metal recovery from the dumps of the many abandoned sulfide mines of Sardinia as the island also hosts major feldspar mines that produce a high amount of carbonate-bearing waste.Selected samples were collected from sulfide-rich lead-zinc Campo Pisano and gold Furtei abandoned mines. The former is part of a giant and high-grade MVT and SEDEX Zn-Pb-Fe district while the latter exploited an epithermal deposit.Mineralogy and chemistry of the samples were determined by XRD and XRF and the acidification potential by standard Lapakko modified Acid Base Accounting tests. Leaching tests simulated the contaminant release from tailings following the Synthetic Precipitation Leaching Procedure. Leachates were analyzed for major and trace elements by ICP-MS and were then buffered with material from feldspar wastes, provided by Minerali Industriali. The Potential Toxic Element contents of buffered materials was also determined by ICP-MS.All samples show positive Net Acid Potential Production, with higher values at Campo Pisano. Leaching tests show pH around 3 and high metal contents at Furtei. Campo Pisano leachates are only slightly acidic and the metal load is much lower due to the initial internal buffering by the carbonate gangue.Buffering with feldspar waste was efficient on highly acidic Furtei samples, even though the amount of buffered material required is high. Doping feldspar waste with carbonate-rich limestone waste grants the same buffering capacity at a highly reduced amount of buffering agent added.The results show that limestone waste-doped feldspar waste can be an effective acid buffering agent both for mixing with secondary tailings and for treatment of polluted acidic waters.ReferencesGrieco, G., Sinojmeri, A., Bussolesi, M., Cocomazzi, G. and Cavallo, A. (2021). Environmental impact variability of copper tailing dumps in Fushe Arrez (Northern Albania): The role of pyrite separation during flotation. Sustainability, 13(17), 9643.

We compute, via motivic wall-crossing, the generating function of virtual motives of the Quot scheme of points on ${\mathbb{A}}^3$ , generalising to higher rank a result of Behrend–Bryan–Szendrői. We show that this motivic partition function converges to a Gaussian distribution, extending a result of Morrison.

Technological advances in massively parallel sequencing have led to an exponential growth in the number of known protein sequences. Much of this growth originates from metagenomic projects producing new sequences from environmental and clinical samples. The Unified Human Gastrointestinal Proteome (UHGP) catalogue is one of the most relevant metagenomic datasets with applications ranging from medicine to biology. However, the lack of sequence annotation impairs its usability. This work aims to produce a family classification of UHGP sequences to facilitate downstream structural and functional annotation. This is achieved through the release of theDPCfam-UHGP50 datasetcontaining 10,778 putative protein families generated using DPCfam clustering, an unsupervised pipeline grouping sequences into multi-domain architectures. DPCfam-UHGP50 considerably improves family coverage at protein and residue levels compared to the manually curated repository Pfam. It is our hope that DPCfam-UHGP50 will foster future discoveries in the field of metagenomics of the human gut by the release of a FAIR-compliant database easily accessible via a searchable web server and Zenodo repository.

Protein language models (pLMs) transform their input into a sequence of hidden representations whose geometric behavior changes across layers. Looking at fundamental geometric properties such as the intrinsic dimension and the neighbor composition of these representations, we observe that these changes highlight a pattern characterized by three distinct phases. This phenomenon emerges across many models trained on diverse datasets, thus revealing a general computational strategy learned by pLMs to reconstruct missing parts of the data. These analyses show the existence of low-dimensional maps that encode evolutionary and biological properties such as remote homology and structural information. Our geometric approach sets the foundations for future systematic attempts to understand thespaceof protein sequences with representation learning techniques.

Deep Learning models for protein structure prediction, such as AlphaFold2, leverage Transformer architectures and their attention mechanism to capture structural and functional properties of amino acid sequences. Despite the high accuracy of predictions, biologically insignificant perturbations of the input sequences, or even single point mutations, can lead to substantially different 3d structures. On the other hand, protein language models are often insensitive to biologically relevant mutations that induce misfolding or dysfunction (e.g. missense mutations). Precisely, predictions of the 3d coordinates do not reveal the structure-disruptive effect of these mutations. Therefore, there is an evident inconsistency between the biological importance of mutations and the resulting change in structural prediction. Inspired by this problem, we introduce the concept of adversarial perturbation of protein sequences in continuous embedding spaces of protein language models. Our method relies on attention scores to detect the most vulnerable amino acid positions in the input sequences.Adversarial mutationsare biologically diverse from their references and are able to significantly alter the resulting 3d structures.

We prove that, given integers $m\geq 3$, $r\geq 1$ and $n\geq 0$, the moduli space of torsion free sheaves on $\mathbb P^m$ with Chern character $(r,0,\ldots,0,-n)$ that are trivial along a hyperplane $D \subset \mathbb P^m$ is isomorphic to the Quot scheme $\mathrm{Quot}_{\mathbb A^m}(\mathscr O^{\oplus r},n)$ of $0$-dimensional length $n$ quotients of the free sheaf $\mathscr O^{\oplus r}$ on $\mathbb A^m$., Minor improvements. Final version

The progressive depletion of the main feldspathic flux deposits in the World is forcing the ceramic industry to search for suitable substitutes. The aim of this study is to assess the potential of some feldspar sources in the Egyptian Eastern Desert, particularly syenites from Abu Khruq, in the manufacture of ceramic tiles. Beneficiated samples obtained by lab-scale mineral processing were tested into porcelain stoneware batches (from 10% to 30% wt in replacement of feldspars) and compared with a reference body through a laboratory reproduction of the industrial processing. The technological behavior of unfired tiles does not suffer any significant alteration due to the use of syenites. On the other hand, syenite-bearing bodies exhibit some changes in the phase composition and the chemistry of the melt, which turns richer in alkali, especially K2O. The consequently increased sintering rate depends mainly on the viscosity of the liquid phase formed during firing. In conclusion, syenites can be used without technological hindrances to manufacture porcelain stoneware tiles. The firing behavior of syenite-bearing batches can be reasonably adjusted by setting key parameters (e.g., the feldspar amount and the Na/K ratio), but the color of fired bodies requires to furtherly lower the iron oxide.

This paper is motivated by the question of how motivic Donaldson--Thomas invariants behave in families. We compute the invariants for some simple families of noncommutative Calabi--Yau threefolds, defined by quivers with homogeneous potentials. These families give deformation quantizations of affine three-space, the resolved conifold, and the resolution of the transversal $A_n$-singularity. It turns out that their invariants are generically constant, but jump at special values of the deformation parameter, such as roots of unity. The corresponding generating series are written in closed form, as plethystic exponentials of simple rational functions. While our results are limited by the standard dimensional reduction techniques that we employ, they nevertheless allow us to conjecture formulae for more interesting cases, such as the elliptic Sklyanin algebras.

This paper presents new data on platinum-group-mineral (PGM)-bearing chromitites from the Ranomena mine, the only past-producing chromite mine in the North Toamasina chromite district of Eastern Madagascar. Such data can provide an insight on tectonic setting that led to emplacement of their host ultramafic body and can help to highlight the differences with other chromite deposits of Madagascar. Chromitite host rocks are harzburgite and pyroxenite and gangue minerals are orthopyroxene and minor olivine. Chromite mineral chemistry shows a strong affinity with chromitites from layered intrusions and PGE patterns are similar to those from the stratigraphically lowest chromitites in the Bushveld Complex. PGMs are dominated by laurite and are free of alloys. PGE mineralogy is consistent with early crystallization of laurite–erlichmanite at low fS2. Previous studies have suggested that the North Toamasina ultramafic bodies are fragments of dismembered ophiolites and that their presence within the so-called suture zone supports the suggestion that they mark the closure of an ocean between east and west Gondwana. Even though these ultramafic bodies have been interpreted as ophiolitic, our data better support an origin as small layered intrusions, rather than as fragments of oceanic crust.

Bulbourethral transobturator sling data from other investigators report a success rate from 53% to 85%. Since the degree of sling tension and its adjustment seems to be important for achieving complete urinary continence we present results on the first consecutive 12 patients, with mild post prostatectomy stress urinary incontinence--defined as--less than 500 ml, who underwent a new perineal tensive transobturator polypropylene tape (T-TOT) procedure at our institution.Pre-operative mean abdominal leak point pressure (ALPP) was 23 cm H2O (sd +/- 10), retrograde leak point pressure (RLPP) was 24 cm H2O (sd +/- 6) and the mean pad test was 324 g (sd +/- 176). The overall success rate has been of 58.3% (7 patients) complete responders (CR), 33.3% (4 pts) partial responders (PR) and 8.33% (1 patient) failure. No significant urodynamic outlet obstruction nor urethral erosion occurred at 9-month follow up occurred. Post operative ICIQ-SF questionnaire score dropped from 11 to 3 with significant statistical evidence (p0.01).Perineal T-TOT showed safe and effective results similar to conventional bulbourethral transobturator male slings without obstructive symptoms despite maximal tension was used. Anyway longer prospective follow up is needed to determine the long-term efficacy of this procedure and the effective preservation from urethral erosion.

The surgical therapy of the urethral strictures is still controversial as it interests the choice of an appropriate technique among many methods. In cases of complex urethral strictures, urethroplasties using genital or extragenital tissue for reconstruction are indicated. Scrotal in-lay was popular some years ago, but the complications rate was high. Nowdays, the two techniques with better outcome are the mesh graft urethroplasty and the buccal mucosa on-lay urethroplasty.