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A topological space X is monotonically star countable if for every open cover u of X we can assign a subspace s(u) ⊆ X, called the kernel, such that s(u) is a countable subset of X, and st(s(u), u) = X, and if V refines u, then s(u) ⊆ s(V), where st(s(u), u) = S {u ∈ u : u ∩ s(u) ≠ ∅}. In this paper we study the relation between monotonically star countable spaces and related spaces, and we also study topological properties of monotonically star countable spaces. [ABSTRACT FROM AUTHOR]

This article reviews the characteristics and construction methods of petroleum hydrocarbon degrading bacterial consortia, especially highlights the theory and principles underlying the consortium construction, the strategies of bacterium selection/combination, and the recent application in the remediation of petroleum hydrocarbon polluted environment. The future focus of the studies in this field was proposed, which includes the further exploring the application of efficient and convenient genome engineering technology, the regulation mechanism of microbial metabolic network and the path way identification of petroleum hydrocarbon degradation. [ABSTRACT FROM AUTHOR]

Due to the growing demand for clean renewable hydrogen fuel, the rational design of electrode materials' composition and structure holds significant importance in achieving efficient energy storage and conversion in electrochemical energy devices. In this study, we synthesize NiCo-MOF74/NF substrate using a one-step hydrothermal method, after which we successfully deposit a layer of Ru metal nanoclusters on the substrate by electrodeposition. Ru NCs@NiCo-MOF74/NF exhibits an exceptionally large specific surface area and excellent interface effects, demonstrating outstanding performance in both overall water splitting and supercapacitor applications. In a 1 M KOH alkaline solution, the device requires only 1.47 V output voltage to deliver a current density of 10 mA cm−2 for overall water splitting. As a supercapacitor, the unique nanoflower structure of Ru NCs@NiCo-MOF74/NF enables fast and reversible Faradaic reactions, providing high specific capacitance and rate performance. It shows a high areal capacitance of 1.664 mAh cm−2 at 1 mA cm−2, indicating excellent charge storage capacity. Assembled into an asymmetric supercapacitor (ASC) with Ru NCs@NiCo-MOF74/NF as the positive electrode, the device achieves a high energy density of 511.88 μWh cm−2 at a power density of 545.68 μW cm−2. After 5000 cycles, the capacitance retention rate is approximately 100 %, demonstrating remarkable cycling stability. This paves the way for the synthesis of multifunctional catalysts, opening up new possibilities in the field. • NiCo-MOF74 nanoarrays loaded with Ru nanoclusters were successfully prepared. • Ru NCs@NiCo-MOF74/NF exhibits excellent electrochemical activity. • Ru NCs@NiCo-MOF74/NF electrode exhibits excellent stability. [ABSTRACT FROM AUTHOR]

• A novel Mn-doped NiFe 2 O 4 nanosheet array was prepared using simple in situ etching and annealing. • The capacitance performance is greatly improved by adjusting the morphology of nanobelt by Mn ions. • The assembled supercapacitor achieves a high energy density of 390 µWh cm−2 at a power density of 544 µW cm−2. This research presents an innovative approach to the in-situ fabrication of Mn-doped NiFe 2 O 4 (Mn-NiFe 2 O 4) nanosheet arrays directly on nickel foam substrates. The formation of precursors on the nickel foam substrates is achieved through spontaneous corrosion, followed by a thermal treatment to form the Mn-NiFe 2 O 4 nanosheet arrays. The material's structure and morphology were thoroughly examined, revealing that the addition of Mn transforms the nanoporous structure on the nickel foam into a nanosheet structure. The average thickness of the nanosheets is 30 nm, and their primary composition is Mn-doped NiFe 2 O 4. The resulting highly porous structure of these nanosheets provides numerous active sites and effective electron and ion diffusion channels, thereby increasing charge density and mechanical stability. Electrochemical assays show that the areal-specific capacity of the synthesized electrode material reaches 4.34 C cm−2 (areal-specific capacitance is 8.68 F cm−2) at 1 mA cm−2. Notably, the constructed hybrid supercapacitor achieves a power density of 544 µW cm−2 at an energy density of 390 µWh cm−2. Furthermore, capacitance retention is 95.2% after 5000 charging cycles. Additionally, the assembled device delivers robust and sustained energy output for LED displays and electric toy cars. This method streamlines the production flow of electrode materials, reducing energy consumption while significantly enhancing the areal capacitance of supercapacitors. The assembled hybrid supercapacitor structure diagram and the assembled devices provide power sources for electric toy cars and LED displays. [Display omitted] [ABSTRACT FROM AUTHOR]

Molecular phosphorescence in the second near‐infrared window (NIR‐II, 1000–1700 nm) holds promise for deep‐tissue optical imaging with high contrast by overcoming background fluorescence interference. However, achieving bright and stable NIR‐II molecular phosphorescence suitable for biological applications remains a formidable challenge. Herein, we report a new series of symmetric isocyanorhodium(I) complexes that could form oligomers and exhibit bright, long‐lived (7–8 μs) phosphorescence in aqueous solution via metallophilic interaction. Ligand substituents with enhanced dispersion attraction and electron‐donating properties were explored to extend excitation/emission wavelengths and enhanced stability. Further binding the oligomers with fetal bovine serum (FBS) resulted in NIR‐II molecular phosphorescence with high quantum yields (up to 3.93 %) and long‐term stability in biological environments, enabling in vivo tracking of single‐macrophage dynamics and high‐contrast time‐resolved imaging. These results pave the way for the development of highly‐efficient NIR‐II molecular phosphorescence for biomedical applications. [ABSTRACT FROM AUTHOR]

Molecular phosphorescence in the second near‐infrared window (NIR‐II, 1000–1700 nm) holds promise for deep‐tissue optical imaging with high contrast by overcoming background fluorescence interference. However, achieving bright and stable NIR‐II molecular phosphorescence suitable for biological applications remains a formidable challenge. Herein, we report a new series of symmetric isocyanorhodium(I) complexes that could form oligomers and exhibit bright, long‐lived (7–8 μs) phosphorescence in aqueous solution via metallophilic interaction. Ligand substituents with enhanced dispersion attraction and electron‐donating properties were explored to extend excitation/emission wavelengths and enhanced stability. Further binding the oligomers with fetal bovine serum (FBS) resulted in NIR‐II molecular phosphorescence with high quantum yields (up to 3.93 %) and long‐term stability in biological environments, enabling in vivo tracking of single‐macrophage dynamics and high‐contrast time‐resolved imaging. These results pave the way for the development of highly‐efficient NIR‐II molecular phosphorescence for biomedical applications. [ABSTRACT FROM AUTHOR]

A space X is said to be cellular-Lindelöf if, for every family U of disjoint non-empty open sets of X, there is a Lindelöf subspace L ⊂ X , such that U ∩ L ≠ ∅ for every U ∈ U . This class of spaces was introduced by Bella and Spadaro in 2007. In this paper, our main result is to show that the Pixley–Roy space F [ X ] is cellular-Lindelöf if and only if it is CCC. We also establish a cardinal inequality for cellular-Lindelöf spaces which have a symmetric g-function. Some open questions are posed. [ABSTRACT FROM AUTHOR]

In this paper, we prove that if 2λ<κ and A [κ]λ is a MADF then the generalized Mrówka space Ψ(A∖B) has no Gλ-diagonal, where B A and |B|≤λ. If a topological space X has a regular Gλ-diagonal and a local decreasing base of cardinality χ(X) for each x X, then |X|≤2dc(X) χ(X) λ, where dc(X) is the discrete cellularity of X and χ(X) is the character of X. As a corollary, we prove that if X is a DCCC (and hence, DC(ω1), weakly Lindelöf or star Lindelöf) first countable space with a regular Gδ-diagonal then |X|≤2ω, which gives a positive answer to a question in [17]. Finally, we give another counterexample to a question of Ginsburg and Woods [6], which has nicer properties than the counterexamples constructed in [15] and [16]. [ABSTRACT FROM AUTHOR]

Thermoplastic elastomer (TPE) is a kind of new automotive interior material with high elasticity and strength. Traditional TPE materials were difficult to meet the new requirements of large-scale automotive interior parts with complex shape. In this study, the TPE material was prepared using different mass ratios with homopolymer polypropylene (PP), styrene-ethylene/butene-styrene copolymer (SEBS), naphthene oil (NO), magnesium stearate (MGST), and polytetrafluoroethylene (PTFE). A quality-prediction and multiobjective optimization method based on a genetic algorithm was applied. The parameters that had an important effect on the forming quality were selected using an orthogonal testing method. Results showed that using the proposed method, a new TPE material is obtained with excellent scratch resistance ability and high MFI. The mechanisms of the addition of PTFE and MGST were analysed according to SEM images. The peel strength of the optimized part was measured to prove the coating quality of TPE material. [ABSTRACT FROM AUTHOR]

A space X is said to be star determined by compact metrizable subspaces (star-CM for short) if for any open cover U of X there is a compact and metrizable subspace Y ⊂ X such that St (Y , U) = X . This notation of star-CM was introduced by van Mill, Tkachuk and Wilson in (Topol Appl 154:2127–2134, 2007). In this paper, we investigate the relations between star-CM spaces and related spaces, and study topological properties of star-CM spaces. We also establish a cardinal theorem for star-CM spaces with symmetric g-functions. [ABSTRACT FROM AUTHOR]

A space X is monotonically star σ-compact if one assigns to each open cover U of X a subspace s(U) ⊆ X, called a kernel, such that s(U) is a σ-compact subset of X, and st(s(U),U) = X, and if V refines U then s(U) ⊆ s(V), where st(s(U),U) = ⋃{U ∈ U : U∩s(U) ≠ ∅}. In this paper, we investigate the relationship between monotonically star σ-compact spaces and related spaces, and also study topological properties of monotonically star σ-compact spaces. [ABSTRACT FROM AUTHOR]

Bal and Kočinac in [2] introduced and studied the class of selectively star-ccc spaces. A space X is called selectively star-ccc if for every open cover U of X and for every sequence (A n : n ∈ ω) of maximal pairwise disjoint open families in X , there exists a sequence (A n : n ∈ ω) such that A n ∈ A n for every n ∈ ω and St (⋃ n ∈ ω A n , U) = X. In this paper, we show that there exists a Tychonoff selectively 2-star-ccc space which is neither strongly star Lindelöf nor selectively star-ccc, which gives a positive answer to a question of Bal and Kočinac [2]. Under 2 ℵ 0 = 2 ℵ 1 , we even provide a normal example of a selectively 2-star-ccc space which is neither strongly star Lindelöf nor selectively star-ccc. Finally, we prove that every open F σ -subset of a selectively star-ccc space is selectively star-ccc. Some new questions are also posed. [ABSTRACT FROM AUTHOR]

The class of weakly linearly Lindelöf spaces was introduced and studied by Juhász, Tkachuk and Wilson in [7]. Recall that a space X is weakly linearly Lindelöf if for any family U of non-empty open subsets of X of regular uncountable cardinality κ , there exists a point x ∈ X such that every neighborhood of x meets κ -many elements of U. In this paper, we show that: (1) If X is a weakly linearly Lindelöf space and U is an open cover of X , then for the open cover { St 2 (x , U) : x ∈ X } of X , there exists a countable subset A ⊂ X such that St 2 (A , U) ‾ = X ; (2) Every weakly linearly Lindelöf normal metaLindelöf space is weakly Lindelöf; (3) If X is a first countable regular space, then M (X) (generated by Moore Machine) is weakly linearly Lindelöf if and only if X is weakly linearly Lindelöf; (4) Every product of a weakly linearly Lindelöf space and a space of countable spread (or a separable space) is weakly linearly Lindelöf; (5) If a subspace X ⊂ ω 1 ω is weakly linearly Lindelöf, then X is second countable (and hence, metrizable); (6) If X is a weakly linearly Lindelöf Baire space with a rank 2-diagonal such that w e (X) ≤ ω 1 , then | X | ≤ c ; (7) The space X is cellular-WLL if and only if it is weakly linearly Lindelöf. [ABSTRACT FROM AUTHOR]

In financial optimization problem, the optimal portfolios usually depend heavily on the distributions of uncertain return rates. When the distributional information about uncertain return rates is partially available, it is important for investors to find a robust solution for immunization against the distribution uncertainty. The main contribution of this paper is to develop an ambiguous value-at-risk (VaR) optimization framework for portfolio selection problems, where the distributions of uncertain return rates are partially available. For tractability consideration, we deal with new safe approximations of ambiguous probabilistic constraints under two types of random perturbation sets and obtain two equivalent tractable formulations of the ambiguous probabilistic constraints. Finally, to demonstrate the potential for solving portfolio optimization problems, we provide a practical example about the Chinese stock market. The advantage of the proposed robust optimization method is also illustrated by comparing it with the existing optimization approach via numerical experiments. [ABSTRACT FROM AUTHOR]

Abstract Given a topological property (or a class) P , the class P ′ consists of spaces X such that for any neighbourhood assignment ϕ on X , there exists a subspace Y ⊂ X with property P for which ϕ (Y) = ⋃ { ϕ (y) : y ∈ Y } is dense in X. The class P ′ are called the weak dual of P or weakly dually P (with respect to neighbourhood assignments). We establish that DCCC is weakly self-dual in the class of weakly regular spaces. If P ∈ { weakly Lindelöf , CCC , separable } , then P is weakly self-dual in the class of Baire developable spaces. By using Erdös–Radó's theorem, we also prove that: (1) If X is a Baire, weakly dually CCC Hausdorff space with a rank 2-diagonal, then X has cardinality at most 2 ω ; (2) If X is a Baire, weakly dually DCCC Hausdorff space with a rank 3-diagonal, then X has cardinality at most 2 ω ; (3) If X is a weakly dually DCCC Hausdorff space with a rank 4-diagonal, then X has cardinality at most 2 ω. [ABSTRACT FROM AUTHOR]

Abstract Whenever P is a topological property, we say that a topological space X is star P if whenever U is an open cover of X , there is a subspace Y ⊂ X with property P such that St (Y , U) = X. We study the relationships of star P properties for P ∈ { DCCC , weakly Lindelöf , CCC } with other chain conditions. By using Erdös–Radó's theorem, we also establish several cardinal inequalities for star CCC spaces. [ABSTRACT FROM AUTHOR]

Abstract Phytoremediation with aquatic macrophyte has been considered as an eco-friendly technique for controlling harmful cyanobacteria outbreak and proven to be effective. The conventional water quality parameters are frequently measured to evaluate the effectiveness of phytoremediation. However, the concentration of microcystin-leucine-arginine (MC-LR) in different vegetated water still remains uncertain. In this study, the contents of MC-LR in four macrophyte-vegetated lagoons were determined by solid phase extraction and ultra-high-performance liquid chromatography with tandem mass spectrometry technology. Results indicated that MC-LR was found in Nymphaea tetragona lagoon (lagoon-S), Vallisneria spiralis lagoon (lagoon-B) and another Vallisneria spiralis lagoon (lagoon-J). Only in lagoon dominated by Pistia stratiotes L. (lagoon-D), MC-LR concentration was undiscovered regardless of seasonal variation. The levels of MC-LR varied seasonally and were affected by the different vegetated aquatic macrophytes. The results suggest that in addition to conventional physicochemical parameters and indicators of water quality, MC-LR levels should be taken into consideration when the effectiveness of phytoremediation is assessed. Graphical abstract Image 1 Highlights • Eliminating the matrix effects on MC-LR detection occurred in vegetated water environment. • MC-LR concentrations in studied lagoons showed seasonal variation. • Nymphaea tetragona and Pistia stratiotes L. are inclined to inhibit MC-LR releases. • The different vegetated macrophytes and epiphytic materials affected the levels of MC-LR. [ABSTRACT FROM AUTHOR]

Abstract In this paper, we make some observations on chain conditions and dually properties. In particular, we show that: (1) A subspace X ⊂ ω 1 ω is dually CCC then e (X) ≤ ω and a normal subspace X ⊂ ω 1 ω is DCCC if and only if e (X) ≤ ω ; (2) There is a Tychonoff pseudocompact subspace X ⊂ (ω 1 + 1) 2 which is not dually CCC; (3) In the class of o-semimetrizable spaces, dually separable is self-dual with respect to neighbourhood assignments. As an application, we obtain an example of a CCC normal Moore space which is not dually separable under MA+¬CH; (4) There exists an example of a large normal CCC semi-stratifiable space, which answers a question of Xuan and Song (2018) [21, Question 4.11] ; (5) Every dually separable and monotonically monolithic space is Lindelöf, which gives a partial answer to a question of Alas, Junqueira, van Mill, Tkachuk and Wilson (2011) [2, Question 2.1] ; (6) A dually separable Hausdorff space with a strong rank 1-diagonal has cardinality at most 2 c. The conclusion is also true for regular spaces if we replace "strong rank 1-diagonal" with " G δ -diagonal"; (7) A dually separable ω -monolithic Hausdorff space with a G δ -diagonal has cardinality at most c. [ABSTRACT FROM AUTHOR]

Abstract The class of cellular-Lindelöf spaces was introduced and studied by A. Bella and S. Spadaro (2017) [4]. We say that a topological space X is cellular-Lindelöf if for every family U of pairwise disjoint non-empty open sets of X there is a Lindelöf subspace L ⊂ X such that U ∩ L ≠ ∅ , for every U ∈ U. In this paper, we first study topological properties of cellular-Lindelöf spaces, and the relations between cellular-Lindelöf spaces and related spaces. In particular, we obtain a Tychonoff example of a weakly Lindelöf space which is not cellular-Lindelöf, which gives a positive answer to a question of A. Bella and S. Spadaro ([4, Question 2]). We also prove that every monotonically normal W -space is cellular-Lindelöf if and only if it is Lindelöf. Finally, by using Erdös–Radó's theorem, we establish some cardinal inequalities for cellular-Lindelöf spaces. Some new questions are also posed. [ABSTRACT FROM AUTHOR]

Abstract Oocyte meiosis is a complex process coordinated by multiple endocrinal and molecular circuits. Recently, N6-methyladenosine (m6A) epigenetic modification on RNA is revealed to be important for meiotic maturation. However, the molecular mechanism of how m6A modification exerts its effect on oocyte maturation is largely unknown. Here, we showed that endogenous m6A writers (Mettl3 and Wtap) and eraser (Fto) elevated their transcript levels during meiotic maturation of pig oocytes. From germinal vesicle (GV) to metaphase II (MII) stages, global m6A level significantly increased, and existed mostly in ooplasm. Methyl donor (betaine, 16 mM) treatment of porcine cumulus-oocyte complexes (COCs) during in vitro maturation (IVM) significantly boosted nucleic acid m6A level within oocytes, but unchanged meiotic process and oocyte subsequent development. By contrast, methylation inhibitor (cycloleucine, 20 mM) reduced nucleic acid m6A level, and significantly decreased the germinal vesicle breakdown (GVBD) rate, the extrusion rate of the first polar body, and the cleavage and blastocyst rates of parthenotes. In addition, in cycloleucine-treated oocytes Wtap increased but Lin28 decreased their abundances significantly, along with the higher incidence of spindle defects and chromosome misalignment. Furthermore, pT161-CDK1 protein level in pig oocytes was confirmed to be decreased after cycloleucine treatment for 24 h. Taken together, chemical induced reduction of nucleic acid m6A methylation during pig oocyte meiosis could impair meiotic maturation and subsequent development potency, possibly through down-regulating pluripotency marker Lin28 mRNA abundance and disturbing MPF-regulated chromosome/spindle organization. Highlights • Endogenous m6A writers Mettl3 and Wtap, eraser Fto elevated their transcript levels in maturing pig oocytes. • Global m6A modification level significantly increased in maturing pig oocytes. • Betaine treatment significantly boosted m6A level, but unaffected oocyte meiosis and subsequent development ability. • Cycloleucine treatment significantly reduced m6A level, that impaired meiotic maturation and subsequent development potency. • Cycloleucine could down-regulate Lin28 and disturb MPF-regulated chromosome/spindle organization to affect porcine oocytes. [ABSTRACT FROM AUTHOR]

We prove that a Hausdorff metaLindelöf weakly star countable space is feebly Lindelöf and a Hausdorff metacompact weakly star finite space is almost compact which partially answers a question of Alas and Wilson (2017) [2, Question 3.14] . We also obtain a normal example of a weakly star countable space which is neither almost star countable nor star Lindelöf without any set-theoretic assumptions, which answers a question implicitly asked by Song (2015) [13, Remark 2.8] and a question asked by Alas, Junqueira and Wilson (2011) [3, Question 4] . Under MA+¬CH, there even exists a normal weakly star countable Moore space which is not almost star countable. An example of a Tychonoff star compact and weakly star finite space which is not star countable is also given. Finally, we prove that every weakly star countable Hausdorff space with a rank 4-diagonal has cardinality at most 2 ω . [ABSTRACT FROM AUTHOR]

A space X is weakly star countable if for each open cover U of X there exists a countable subset F of X such that Ux∈FSt(x; U) = X. In this paper, we investigate topological properties of weakly star countable spaces. [ABSTRACT FROM AUTHOR]

The strengthening mechanism of an ultrasonic vibration-strengthened adhesive bonding method was studied via experimental and numerical analyses. This processing method was found to enhance the bonding strength and stability of CFRP-to-aluminum joints by 40% and 60%, respectively. Ultrasonic vibration could promote the flow of adhesive to fill the bonding gap through the vibration conversion and transmission in the CFRP laminate. The high-frequency vibration of the adhesive caused large bubbles in the adhesive layer to stretch, deform towards the nearby flow front and burst on account of the asymmetric resistance offered by the bubbles to the vibration-induced flow. Ultrasonic vibration made it easier for the adhesive to permeate into the fine structure of the surface, because the permeation was driven by the hydraulic pressure difference produced by the prompted flow of the adhesive. The processing method improves the adhesion strength and bonding stability by utilizing external energy to effectively facilitate the adhesive bonding process; hence, it is an active enhancement method. [ABSTRACT FROM AUTHOR]

A space X is said to be neighborhood star-Menger if for every sequence (Un : n∈N) of open covers of X one can choose finite An ⊆ X, n∈N such that for every open On ⊇ An, n∈N, {St(On, Un) : n∈N} is an open cover of X. We investigate the relationship between neighborhood star-Menger spaces and related spaces, and study the topological properties of neighborhood star-Menger spaces. [ABSTRACT FROM AUTHOR]

A space X is selectively absolutely star-Lindelöf [1,3] if for each open cover U of X and any sequence ( D n : n ∈ ω ) of dense subsets of X , there are finite sets F n ⊆ D n ( n ∈ ω ) such that S t ( ⋃ n ∈ ω F n , U ) = X . In this paper, we continue to investigate topological properties of selectively absolute star-Lindelöf spaces, and show the following statements: (1) There exists a Tychonoff selectively a-star-Lindelöf, pseudocompact space X having a regular closed G δ subset which is not star-Lindelöf (hence not selectively a-star-Lindelöf); (2) Assuming 2 ℵ 0 = 2 ℵ 1 , there exists a normal selectively a-star-Lindelöf space X having a regular closed G δ subset which is not star-Lindelöf (hence not selectively a-star-Lindelöf); (3) An open F σ -subset of a selectively a-star-Lindelöf space is selectively a-star-Lindelöf; (4) For any cardinal κ , there exists a Tychonoff selectively a-star-Lindelöf, pseudocompact space X such that e ( X ) ≥ κ . [ABSTRACT FROM AUTHOR]

The brilliant cresyl blue (BCB) test is used in both basic biological research and assisted reproduction to identify oocytes likely to be developmentally competent. However, the underlying molecular mechanism targeted by the BCB test is still unclear. To explore this question, we first confirmed that BCBpositive porcine oocytes had higher rates of meiotic maturation, better rates of cleavage and development into blastocysts, and lower death rates. Subsequent single-cell transcriptome sequencing on porcine germinal vesicle (GV)-stage oocytes identified 155 genes that were significantly differentially expressed between BCB-negative and BCB-positive oocytes. These included genes such as cdc5l, ldha, spata22, rgs2, paip1, wee1b, and hsp27, which are enriched in functionally important signaling pathways including cell cycle regulation, oocyte meiosis, spliceosome formation, and nucleotide excision repair. In BCB-positive GV oocytes that additionally had a lower frequency of DNA double-strand breaks, the CDC5L protein was significantly more abundant. cdc5l/CDC5L inhibition by short interference (si)RNA or antibody microinjection significantly impaired porcine oocyte meiotic maturation and subsequent parthenote development. Taken together, our single-oocyte sequencing data point to a potential new role for CDC5L in porcine oocyte meiosis and early embryo development, and supports further analysis of this protein in the context of the BCB test. [ABSTRACT FROM AUTHOR]

The Ordovician acritarch genusBarakellaCramer & Díez 1977 and two species,B. felixandB. fortunata, bearing characteristic anastomosing filamentous elements at one pole were first described from the subsurface of the Kasba Tadla Basin, Morocco. Subsequently, another species was described from the South Chinese Ordovician and was later attributed to the genus asBarakella rara. New material from the type locality in Morocco and additional sections in South China are used for a review of the genusBarakella. Based on this review, including statistical analysis,Barakella rarais considered a junior synonym ofBarakella felix.Barakellais a useful taxon for biostratigraphical applications in the Ordovician. Its first appearance datum (FAD) lies in the early Floian (Early Ordovician, time slices 2a–2b) in both South China and Wales. Except for a doubtful record from Sweden, all records ofBarakellaare from the peri-Gondwana margin, making the genus an indicator of the peri-Gondwana palaeoprovince. The appearance ofBarakellain South China indicates thatBarakellapossibly originated in shallow-water nearshore environments, and later spread to offshore environments. [ABSTRACT FROM PUBLISHER]

In the present work, we report a simple method to develop pure copper phosphate nanoflowers without any assistance of additives. The blooming state of these nanoflowers can be controlled precisely by the growth time, pH value, temperature, and component of the precursor solution. A three-step growth mechanism is proposed, and the roles of the different factors are discussed for the formation of the nanoflowers. Relying on the hierarchical porous structure, the nanoflowers exert effective immobilization of enzymes. Compared with the free enzyme, the immobilized one maintains significantly enhanced catalytic activity against extreme pH and temperature variations as well as the presence of a denaturant. Such results can push the development of more hierarchical porous materials which hold promising applications for enzyme immobilization and biotechnology. [ABSTRACT FROM AUTHOR]

In the present work, we report a simple method to develop pure copper phosphate nanoflowers without any assistance of additives. The blooming state of these nanoflowers can be controlled precisely by the growth time, pH value, temperature, and component of the precursor solution. A three-step growth mechanism is proposed, and the roles of the different factors are discussed for the formation of the nanoflowers. Relying on the hierarchical porous structure, the nanoflowers exert effective immobilization of enzymes. Compared with the free enzyme, the immobilized one maintains significantly enhanced catalytic activity against extreme pH and temperature variations as well as the presence of a denaturant. Such results can push the development of more hierarchical porous materials which hold promising applications for enzyme immobilization and biotechnology. [ABSTRACT FROM AUTHOR]

The Early–Middle Ordovician peri-Gondwana and Baltica acritarch provinces are easily recognizable, illustrating a clear provincialism of global phytoplankton. However, acritarch assemblages have been reported to become increasingly similar towards the Late Ordovician, revealing a general cosmopolitanism, although, based on more recent studies, their assemblages from Laurentia and Baltica are reported to be rather different from those from peri-Gondwana. In this decade, new acritarch assemblages reported from South America, the Baltic region, Iran and Siberia, as well as the new material from South China and Tarim, provide additional data that help to understand the palaeobiogeographical distribution and evolution of phytoplankton during the Late Ordovician in more detail. The binary dataset was compiled based on published information from about 120 localities in South China, the Middle East, North Africa, South America, India, Bohemia, Avalonia, Laurentia, Baltica, North China, Tarim and Siberia. This dataset was used for Cluster Analysis (CA), Nonmetric Multidimensional Scaling (NMDS), and Network Analysis (NA) to understand acritarch palaeogeography in the Late Ordovician. Re-evaluation of the global palaeobiogeographical distribution of acritarchs revealed their clear provincialism also during the Late Ordovician, particularly in the Katian. The Late Ordovician acritarch provinces were related to global climatic zones. The highly diverse acritarch assemblage normally existed around 30° in the Southern Hemisphere, which is similar to the latitudinal diversity gradient model proposed by Zacaï et al. (2021) for the Late Ordovician. The total diversity of acritarchs was highest and their palaeobiogeographical differentiation strongest in the Katian. The higher acritarch diversity recorded in this time interval may have resulted from their clearly developed provincialism. Acritarch diversity decreased rapidly at the end of the Ordovician, evidently due to the Late Ordovician Mass Extinction (LOME). The relative proportion of endemic taxa in the assemblages in different regions was very high during the main part of the Late Ordovician. However, as a consequence of the LOME, the relative proportion of cosmopolitan taxa increased in the Hirnantian and became higher than in the Sandbian and Katian. Acritarch assemblages from different plates (regions) reacted to the LOME differently and exhibited various diversity trends. [ABSTRACT FROM AUTHOR]

This paper studies the location–allocation problem of distribution centers (DCs) for fresh products, in which it requires to determine the number and locations of DCs and design the allocation scheme for fresh products. The main challenge in optimizing this problem is to handle the uncertain demands with only partially known probability distribution information. To address this challenge, this paper first characterizes the ambiguous probability distributions of fresh products demands by an ambiguity set. Then, from different perspectives, this paper proposes two distributionally robust (DR) location–allocation models to find the optimal decisions that perform best in view of the worst-case distribution within the ambiguity set. The first model is with ambiguous expectation, which is transformed into a mixed-integer linear programming (MILP) model via employing the linear decision rule technique. The second model is with ambiguous chance constraints. This model is a semi-infinite chance constraint programming problem, which is transformed into a mixed-integer second-order cone programming (MISOCP) model by deriving safe approximations of the ambiguous chance constraints. To verify the feasibility and effectiveness of the proposed models, a case study about Hema fresh chain stores in Beijing is addressed. The experimental results demonstrate that the optimal decision provided by the proposed optimization methods can immunize against ambiguous probability distributions of demands with a small cost price. • Two DR location–allocation models of DCs for fresh products are raised. • The distribution information of uncertain demands is only partially known. • The DR model with ambiguous expectation is transformed into an MILP model. • The DR model with ambiguous chance constraints is transformed into an MISOCP model. • A case study shows the feasibility and effectiveness of the proposed DR models. [ABSTRACT FROM AUTHOR]

The present paper reviews all investigations of Silurian acritarchs in China. Since Silurian acritarchs were first reported in China in 1978, significant progress has been made in Chinese Silurian acritarch research. A total of 30 scientific articles and theses have been published on Silurian acritarchs from China. The majority of these papers recorded acritarchs from South China, and most Silurian acritarch studies concentrated on the Llandovery. Two papers describing material thought to be Silurian have since been shown to be Ordovician acritarch assemblages. We have updated the systematics of the taxa in these reported assemblages and documented their biostratigraphic distribution within China. Investigations of Silurian acritarchs, however, are still very limited, and more research is needed for systematic, biostratigraphic, and palaeoecological interpretations. [ABSTRACT FROM AUTHOR]

Meiotic maturation of mammalian oocytes is a precisely orchestrated and complex process. Dimethyl sulfoxide (DMSO), a widely used solvent, drug, and cryoprotectant, is capable of disturbing asymmetric cytokinesis of oocyte meiosis in mice. However, in pigs, DMSO’s effect on oocyte meiosis still remains unknown. We aimed to evaluate if DMSO treatment will affect porcine oocyte meiosis and the underlying molecular changes as well. Interestingly, we did not observe the formation of the large first polar body and symmetric division for porcine oocytes treated with DMSO, contrary to findings reported in mice. 3% DMSO treatment could inhibit cumulus expansion, increase nuclear abnormality, disturb spindle organization, decrease reactive oxygen species level, and elevate mitochondrial membrane potential of porcine oocytes. There was no effect on germinal vesicle breakdown rate regardless of DMSO concentration. 3% DMSO treatment did not affect expression of genes involved in spindle organization (Bub1 and Mad2) and apoptosis (NF-κB, Pten, Bcl2, Caspase3 and Caspase9), however, it significantly decreased expression levels of pluripotency genes (Oct4, Sox2 and Lin28) in mature oocytes. Therefore, we demonstrated that disturbed cumulus expansion, chromosome alignment, spindle organization and pluripotency gene expression could be responsible for DMSO-induced porcine oocyte meiotic arrest and the lower capacity of subsequent embryo development. Our results provide new insights on DMSO’s effect on porcine oocyte meiosis and raise safety concerns over DMSO’s usage on female reproduction in both farm animals and humans. [ABSTRACT FROM AUTHOR]

In hub location problems, a decision-maker may encounter hybrid uncertain environments where randomness and fuzziness are in the state of affairs. The purpose of this paper is to develop a new two-stage uncapacitated hub location (UHL) problem with recourse, in which uncertain parameters are characterized by both probability and possibility distributions. When demands are the only uncertain parameters, we show that the proposed two-stage UHL model is equivalent to a static optimization problem subject to equilibrium constraint. In the case that the randomness of uncertain demands follows normal distributions, we reduce the equilibrium constraint to its equivalent credibility constraint. Furthermore, when the fuzziness of uncertain demands follows triangular distributions, we discuss the convexity of equilibrium objective function, and establish the equivalent deterministic programming model of the original UHL problem. In general case, we adopt fuzzy simulation (FS) method to approximate uncertain parameters. To solve the proposed hub location problem, we design a hybrid heuristic algorithm by integrating genetic algorithm (GA), variable neighborhood search (VNS) and FS. We conduct some numerical experiments and compare the computational results obtained by the VNS-based GA and standard GA. The computational results together with convergence analysis demonstrate that the VNS-based GA achieves the better performance than standard GA. Finally, we carry out the sensitivity analysis to recognize the most significant parameter of the proposed optimization model. [ABSTRACT FROM AUTHOR]

A space X is star-K-Menger if for each sequence (Un : n ∈ N) of open covers of X there exists a sequence (Un : n ∈ N) of compact subsets of X such that {St(Kn, Un) : n ∈ N} is an open cover of X. In this paper, we construct an example of a Hausdorff star-Menger space that is not star-K- Menger which gives an answer to a question of Song [12], and continue to investigate topological properties of star-K-Menger spaces. [ABSTRACT FROM AUTHOR]

A space X is monotonically star-compact if one can assign to for each open cover U a subspace s ( U ) ⊆ X , called a kernel, such that s ( U ) is a compact subset of X , and st ( s ( U ) , U ) = X , and if V refines U then s ( U ) ⊆ s ( V ) , where st ( s ( U ) , U ) = ⋃ { U ∈ U : U ∩ s ( U ) ≠ ∅ } . In this paper, we investigate topological properties of monotonically star-compact spaces. [ABSTRACT FROM AUTHOR]

A space X is almost Menger (weakly Menger) if for each sequence (Un : n ∊ N) of open covers of X there exists a sequence (Vn : n ∊ N) such that for every n ∊ N, Vn is a finite subset of Un and Un∊NU {V : V ∊ Vn} = X (respectively, Un∊NU{V : V ∊ Vn} = X). We investigate the relationships among almost Menger spaces, weakly Menger spaces and Menger spaces, and also study topological properties of almost Menger spaces and weakly Menger spaces. [ABSTRACT FROM AUTHOR]

A new type of hierarchical hemisphere-likeCaCO3(HSCC) was developed by a biomineralization methodand incorporated into poly(p-dioxanone) (PPDO) by in situring opening polymerization (ROP) to develop thecomposites with comprehensive and good performances. The mechanicalproperty, thermal stability, crystallization behavior, and degradationbehavior of PPDO/HSCC composites were investigated. The tensile strength,the elongation at break, and the modulus of PPDO were enhanced simultaneouslyby the addition of HSCC, because of its good dispersion and interfacialadhesion with PPDO matrix. In addition, HSCC in composites also actedas a nucleating agent and enhanced the crystallinity of PPDO. Thedegradation rate of the PPDO/HSCC composites was enhanced with introducing3 wt % HSCC, while 1 wt % HSCC did not change the degradationrate of PPDO. It was worth mentioning that, compared to PPDO, thepH value of incubation solution was more stable for PPDO/HSCC composites.Because HSCC could neutralized the acid residue, which illustratedthe inflammation risk caused by the acid residue could be reduced.In particular, the good cell attachment and proliferation of bothL929 and MG-63 cells was obtained for PPDO/HSCC with an HSCC amountof 3 wt %. The results indicated hierarchical HSCC played a very importantrole in improving the physical and biological properties of PPDO,which made PPDO/HSCC composites hold a promising application in bonetissue engineering material. [ABSTRACT FROM AUTHOR]

Regeneration of Pb-loaded magnetic biochar prepared with eucalypts leaf residue was studied by using EDTA-2Na as a regenerant. The desorption efficiency was found to be 84.1% in 120 min with iron leaching amount of 1.1 mg g −1 . Higher S BET and pore volume were observed in regenerated magnetic biochars and no significant band shifts occurred in FTIR spectra during 6 regeneration cycles. The decrease of Pb(II) adsorption capacity (from 52.4 to 41.5 mg g −1 ) was only found in the first regeneration cycle. Magnetic separation performance of adsorbents was not significantly affected by multiple regeneration cycles. [ABSTRACT FROM AUTHOR]

To explore genetic mechanism of genetic generalized epilepsies (GGEs) is challenging because of their complex heritance pattern and genetic heterogeneity. KCNJ10 gene encodes Kir4.1 channels and plays a major role in modulating resting membrane potentials in excitable cells. It may cause GGEs if mutated. The purpose of this study was to investigate the possible association between KCNJ10 common variants and the susceptibility and drug resistance of GGEs in Chinese population. The allele-specific MALDI–TOF mass spectrometry method was used to assess 8 single nucleotide polymorphisms (SNPs) of KCNJ10 in 284 healthy controls and 483 Chinese GGEs patients including 279 anti-epileptic drug responsive patients and 204 drug resistant patients. We found the rs6690889 TC+TT genotypes were lower frequency in the GGEs group than that in the healthy controls (6.7% vs 9.5%, p = 0.01, OR = 0.50[0.29–0.86]). The frequency of rs1053074 G allele was lower in the childhood absence epilepsy (CAE) group than that in the healthy controls (28.4% vs 36.2%, p = 0.01, OR = 0.70[0.53–0.93]). The frequency of rs12729701 G allele and AG+GG genotypes was lower in the CAE group than that in the healthy controls (21.2% vs 28.4%, p = 0.01, OR = 0.74[0.59–0.94] and 36.3% vs 48.1%, p = 0.01, OR = 0.83[0.72–0.96], respectively). The frequency of rs12402969 C allele and the CC+CT genotypes were higher in the GGEs drug responsive patients than that in the drug resistant patients (9.3% vs 5.6%, OR = 1.73[1.06–2.85], p = 0.026 and 36.3% vs 48.1%, p = 0.01, OR = 0.83[0.72–0.96], respectively). This study identifies potential SNPs of KCNJ10 gene that may contribute to seizure susceptibility and anti-epileptic drug resistance. [ABSTRACT FROM AUTHOR]

Under expected value of fuzzy variable and continuous Archimedean triangular norms, this paper discusses a renewal process and a renewal reward process for T-independent L - R fuzzy variables in fuzzy decision systems. First, a renewal process with T-independent L - R fuzzy interarrival times is discussed, some limit theorems on renewal variable, average renewal time, and long-term renewal rate in (fuzzy) measure are obtained, and a fuzzy elementary renewal theorem is proved for the limit of the long-term expected renewal rate. Second, a renewal reward process with T-independent L - R fuzzy interarrival times and rewards is discussed, a limit theorem on reward rate in (fuzzy) measure is derived, and a fuzzy renewal reward theorem is proved for the limit value of expected reward rate. Finally, the comparison with stochastic counterparts shows an interesting and reasonable homology in convergence mode and limit value between the results obtained in fuzzy renewal processes and the corresponding results in stochastic renewal processes, though they build on two essentially different mathematical cornerstones, possibility theory and probability theory, respectively. [ABSTRACT FROM AUTHOR]

Magnetic biochar was prepared with eucalyptus leaf residue remained after essential oil being extracted. Batch experiments were conducted to examine the capacity of the magnetic biochar to remove Cr (VI) from electroplating wastewater and to be separated by an external magnetic field. The results show that the initial solution pH plays an important role on both sorption and separation. The removal rates of Cr (VI), total Cr, Cu (II), and Ni (II) were 97.11%, 97.63%, 100% and 100%, respectively. The turbidity of the sorption-treated solution was reduced to 21.8 NTU from 4075 NTU after 10 min magnetic separation. The study also confirms that the magnetic biochar still retains the original magnetic separation performance after the sorption process. [ABSTRACT FROM AUTHOR]

Kočinac and Singh [4] introduced and studied the class of set selectively k-star-ccc spaces. Let k ∈ N , a space X is said to be set selectively k-star-ccc if for each nonempty subset B of X and for every collection U of open sets in X such that B ‾ ⊂ ∪ U and for every sequence (A n : n ∈ N) of maximal cellular open families in X , there is a sequence (A n : n ∈ N) such that for every n ∈ N , A n ∈ A n and B ⊆ S t k (⋃ n ∈ N A n , U). In this paper, we show that for k ∈ N , there exists a Tychonoff pseudocompact selectively 2-star-ccc space X which is not set selectively k-star-ccc, which gives an answer to the Problem 5.1 of [4] , and construct an example of a Tychonoff set selectively star-ccc space having a regular closed G δ -subspace which is not set selectively star-ccc, which gives an answer to the Problem 5.3 of [4]. We also prove that every open F σ -subset of a set selectively star-ccc space is set selectively star-ccc, which gives a positive answer to the Problem 5.6 of [4]. Finally, we obtain a normal example of a selectively 2-star-ccc space X which is neither set strongly star-Lindelöf nor set selectively star-ccc under some set-theoretic assumption, which gives a consistent positive answer to Problem 5.4 of [4]. [ABSTRACT FROM AUTHOR]

New palynological studies from the Xiaoyangqiao section (Jilin Province, north-east China), which has been selected as an Auxiliary Boundary Stratigraphic Section and Point (ASSP) for the base of the Ordovician, confirms the presence of Goniomorpha Yin 1986 in intervals ranging from the late Cambrian (Furongian) to the Early Ordovician (Tremadocian), and allow us to clarify its morphology and affinities. Despite being compared originally to vesicular microfossils with processes arising from one pole, Goniomorpha lacks an enclosed cavity, so it cannot be classified as an acritarch in the strict sense. Instead, we find that the specimens originally described as Goniomorpha are actually part of a wider spectrum of morphologies that are identifiable as the pharyngeal teeth of priapulid worms. The best-preserved specimens resolve the 'processes' as denticles arising from an arch on the margins of a cuticular pad, sometimes with an extending spur and polygonal microstructure. Closely equivalent forms have been reported from Cambrian assemblages of small carbonaceous fossils (SCFs) and in situ on Burgess Shale specimens of the priapulid Ottoia. The findings from the Xiaoyangqiao section extend the taphonomic range of Cambrian-type SCFs into the Ordovician, and provide the first evidence for priapulids from the Ordovician of northern China. More generally, our results demonstrate the reciprocal insights from palynological and SCF-type processing for identifying problematic microfossils. [ABSTRACT FROM AUTHOR]

We explore two different geometric quantum discords defined respectively viathe trace norm (GQD-1) and Hilbert-Schmidt norm (GQD-2) in multipartite systems. A rigorous hierarchy relation is revealed for the two GQDs in a class of symmetric two-qubit X-shape states. For multiqubit pure states, it is found that both GQDs are related to the entanglement concurrence, with the hierarchy relation being saturated. Furthermore, we look into a four-partite dynamical system consisting of two cavities interacting with independent reservoirs. It is found that the GQD-2 can exhibit various sudden change behaviours, while the GQD-1 only evolves asymptotically, with the two GQDs exhibiting different monogamous properties. [ABSTRACT FROM AUTHOR]

We prove exactly that the squared entanglement of formation, which quantifies the bipartite entanglement, obeys a general monogamy inequality in an arbitrary multiqubit mixed state. Based on this kind of exotic monogamy relation, we are able to construct two sets of useful entanglement indicators: the first one can detect all genuine multiqubit entangled states even in the case of the two-qubit concurrence and n-tangles being zero, while the second one can be calculated via quantum discord and applied to multipartite entanglement dynamics. Moreover, we give a computable and nontrivial lower bound for multiqubit entanglement of formation. [ABSTRACT FROM AUTHOR]

In order to make the laboratory testing and management more electronization, automation and intelligence, reduce man-made interference factors, improve the efficiency of the experiment and the accuracy and traceability of the results, etc., the paper puts forward the idea for establishing environmental friendly intelligence laboratory. From the three aspects of laboratory planning, hardware facilities and software, an adaptive ventilation and exhaust gas treatment system is designed. The system can automatic real-time adjust parameters, realize the indoor environment and emissions control automatically, implement networked and visual energy conservation. It achieves the environment friendly in the laboratory. Sample transport, checking inspection process and report are zero distance to communicate with the customers by network. RFID was used to monitor the samples and the main materials management in the whole process, so the testing process and instruments were also controlled. The laboratory quality control level was increased sharply. The processing system can automatically record and calculate instrument data and automatically report. The system reduced the workload improved work efficiency, reduced the human error, and achieved the low carbon energy conservation and emissions reduction. [ABSTRACT FROM AUTHOR]

Acritarchs and prasinophytes representing 39 species in 26 genera are identified from the Early–Middle Ordovician Meitan Formation in the Guanyinqiao section, Qijiang, Chongqing in South China. This palynomorph assemblage is dominated by the generaPolygonium(35.2%),Striatotheca(15.2%),Stelliferidium(12.5%) andLeiosphaeridia(10.2%) showing similarities to assemblages fromdeflexus–suecicusgraptolite biozone (Meitan Formation, upper Floian–lower Dapingian) in the Honghuayuan section and can be correlated to the contemporaneous global acritarch assemblages. The composition of the acritarch assemblage from the Meitan Formation of the Guanyinqiao section implies an inner-shelf depositional environment for the studied successions. [ABSTRACT FROM AUTHOR]

To solve the problems of ventilation design unscientific, running instability, high energy consumption and exhaust gas processing difficulties in the large-scale laboratory, the design of a fully automatic control of the closed-loop negative pressure adaptive ventilation and exhaust gas disposal systems was made. The ventilation characteristics and requirements of a large-scale comprehensive laboratory were analyzed, and integrated into the new design concept. Focus on the design of the closed-loop piping and the negative pressure adaptive ventilation system, the design of the exhaust gas treatment system, and the automatic control system. The adaptive regulation system in the ventilation frequency energy saving, emission environmental treatment and monitoring automatically run superiority. This design results has been fully completed made in an inspection and quarantine laboratory. The system was stable, good ventilation, waste gas treatment fully meet the requirements of environmental protection, energy-saving remarkable, and achieved a good human-computer interaction of visual automatic control, fully meet the design requirements. It will be a good reference for large-scale laboratory ventilation and waste gas disposal system design. [ABSTRACT FROM AUTHOR]