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The beneficial effect of microbially induced carbonate precipitation on building materials has been gradually disclosed in the last decade. After the first applications of on historical stones, promising results were obtained with the respect of improved durability. An extensive study then followed on the application of this environmentally friendly and compatible material on a currently widely used construction material, concrete. This review is focused on the discussion of the impact of the two main applications, bacterial surface treatment and bacteria based crack repair, on concrete durability. Special attention was paid to the choice of suitable bacteria and the metabolic pathway aiming at their functionality in concrete environment. Interactions between bacterial cells and cementitious matrix were also elaborated. Furthermore, recommendations to improve the effectiveness of bacterial treatment are provided. Limitations of current studies, updated applications and future application perspectives are shortly outlined.

Microbial-induced CaCO 3 precipitation has been widely applied in bacterial-based self-healing concrete. However, the limited biogenetic CaCO 3 production by bacteria after they were introduced into the incompatible concrete matrix is a major challenge of this technology. In the present study, the potential of combining two metabolic pathways, urea hydrolysis and nitrate reduction, simultaneously in one bacteria strain for improving the bacterial CaCO 3 yield has been investigated. One bacterial strain, Ralstonia eutropha H16, which has the highest Ca 2+ tolerance and is capable of performing both urea hydrolysis and nitrate reduction in combined media was selected among three bacterial candidates based on the enzymatic examinations. Results showed that H16 does not need oxygen for urea hydrolysis and urease activity was determined primarily by cell concentration. However, the additional urea in the combined medium slowed down the nitrate reduction rate to 7 days until full NO 3 − decomposition. Moreover, the nitrate reduction of H16 was significantly restricted by an increased Ca 2+ ion concentration in the media. Nevertheless, the overall CaCO 3 precipitation yield can be improved by 20 to 30% after optimization through the combination of two metabolic pathways. The highest total CaCO 3 precipitation yield achieved in an orthogonal experiment was 14 g/L. It can be concluded that Ralstonia eutropha H16 is a suitable bacterium for simultaneous activation of urea hydrolysis and nitrate reduction for improving the CaCO 3 precipitation and it can be studied later, on activation of multiple metabolic pathways in bacteria-based self-healing concrete.

Renicoris gen. nov. and its type species Renicoris robustus sp. nov. (Hemiptera: Heteroptera: Reduviidae: Harpactorinae) from Yunnan, China, are described and illustrated. A key to separate the new genus and its closely related genera is provided.

A new species, Dindymus albonotum Zhao & Cao, sp. nov. , and two newly recorded species, Euscopus robustus Stehlík, 2005 and Brancucciana (Rubriascopus) orientalis Stehlík & Jindra, 2008, belonging to the family Pyrrhocoridae Amyot & Serville, 1843 (Hemiptera, Heteroptera, Pyrrhocoroidea) from China are described and illustrated.

Magnesium slag (MS) is a solid by-product during magnesium production using the Pidgeon process. Around 5–6 million tons of magnesium slag was produced in China in 2023, which accounted for 83% of the total disposal of magnesium slag worldwide. To explore the innovative and high-end application of MS in building materials, this study investigated the preparation of calcium carbonate cementitious composites produced by high-volume (80%) MS and 20% of traditional ordinary Portland cement (OPC), low-carbon cement–calcium sulfoaluminate cement (CSA), or green cement–alkali-activated materials after CO2 curing. The effects of OPC, CSA, and AAM on the performance evolution of MS blends before and after carbonation curing were analyzed. The results indicated that AAM contributed to a superior initial strength (7.38 MPa) of MS composites after standard curing compared to OPC (1.18 MPa) and CSA (2.72 MPa). However, the lack of large pores (around 1000 nm) in the AAM-MS binder caused the slowest CO2 penetration during the carbonation curing period compared to the OPC- and CSA-blended samples. Less than 3 days were required for the full carbonation of the CSA- and OPC-blended MS mortar, while 7 days were required for the AAM blends. After carbonation, the OPC-blended MS exhibited the highest strength performance of 51.58 MPa, while 21.38 MPa and 9.3 MPa were reached by the AAM- and CSA-blended MS mortars, respectively. OPC-blended MS composites exhibited the highest CO2 uptake of 13.82% compared to the CSA (10.85%) and AAM (9.41%) samples. The leaching of Hg was slightly higher than the limit (<50 µg/L) in all MS mortars, which should be noticed in practical application.

The recycling of coal gangue has considerable potential to produce secondary environmental hazards, which significantly influence the high-end application of coal gangue in practical engineering. The present study investigates the effects of activation treatment on the physical, chemical properties and leaching behavior of coal gangue. The mineral composition, micro-pore structure and element leaching were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Thermogravimetry Analysis (TG), Low-Temperature Nitrogen Adsorption (LTNA) and Inductively Coupled Plasma (ICP). The results indicate that kaolinite and pyrite in coal gangue experienced reconstruction after 600 °C during thermal activation. The density of thermally activated coal gangue is increased with the calcination temperature as well as the alkalinity (from 4.8–7.1) due to the burning of organic and the oxidation of pyrite. The calcination treatment induced the reduction in macropore volume (>50 nm), and enhancement in mesopore (<5 nm) volume. Leachable Ni, Cd, Mn, Cu, Zn and Pd decreased by 99%, 67%, 86%, 40%, 99% and 93% after calcination at 800 °C, respectively. The Si and Al in 800 °C calcined coal gangue exhibited a high leaching ability in alkalinity solution; leachable Al reached 106.4 mg/kg, while leachable Si reached 86.1 mg/kg after 48 h of dynamic leaching.

Background China’s HIV-1 epidemic originated in the border regions of Yunnan Province in the late 1980s. Although domestic transmission has been effectively contained in recent years, the border regions continue to face public health challenges. In order to track the dynamic transmission of HIV-1, a molecular epidemiology study was conducted in a China-Myanmar-Laos border area. Methods Between 2022 and 2023, 570 individuals newly diagnosed with HIV/AIDS were recruited in Xishuangbanna prefecture. The viral gene sequences were obtained through amplification and sequencing. The characteristics of the HIV-1 genotype distribution, genetic drug resistance and molecular networks were analyzed to identify relevant influencing factors. Results Of 486 samples that were genotyped, 16 different HIV-1 genotypes were identified. The predominant strains were CRF08_BC (41.5%), CRF01_AE (20.1%), CRF07_BC (16.6%) and unique recombinant forms (URFs, 13.1%). The main HIV-1 genotypes exhibited specific associations with demographic factors, including registered residence, age, education level, infection status and reported area. The analysis of the dynamic molecular network revealed that local registered residence and age groups of 29 years and under and 50–59 years, were linked to network expansion. The overall prevalence of sequences carrying drug resistance-associated mutations (DRMs) was 39.1% (195/499). HIV-1 genotypes were significantly associated with the distribution of DRMs. High-frequency resistance mutations exhibited genotype-specific distributions: V179D/VD and V179E of NNRTIs were significantly associated with CRF08_BC and “other” genotypes, respectively; S68G/SG of NRTIs was significantly associated with CRF01_AE. Drug-resistant strains were most prevalent among divorced/widowed individuals (OR = 1.799, 95% CI: 1.025–3.157) and in those infected with CRF08_BC (OR = 2.981, 95% CI: 1.434–6.194). URFs were found to have a significantly higher risk of resistance to PIs (OR = 12.649, P  = 0.002), while CRF08_BC was found to have a higher risk of resistance to NNRTIs (OR = 4.138, P  = 0.004). Conclusion This study revealed the genetic diversity of HIV-1 and increasing drug resistance, as well as the transmission dynamics, in a high-risk transnational border region. The findings emphasized the importance of HIV-1 molecular surveillance in exploring high-risk populations and developing public health strategies to reduce HIV-1 transmission and control drug resistance in this area.

Most assassin bugs are predators that act as important natural enemies of insect pests. Mitochondrial (mt) genomes of these insects are double-strand circular DNAs that encode 37 genes. In the present study, we explore the duplication and rearrangement of tRNA genes in the mt genome of Reduvius tenebrosus, the first mt genome from the subfamily Reduviinae. The gene order rearranges from CR (control region)-trnI-trnQ-trnM-ND2 to CR-trnQ-trnI2-trnI1-trnM-ND2. We identified 23 tRNA genes, including 22 tRNAs commonly found in insects and an additional trnI (trnI2), which has high sequence similarity to trnM. We found several pseudo genes, such as pseudo-trnI, pseudo-CR, and pseudo-ND2, in the hotspot region of gene rearrangement (between the control region and ND2). These features provided evidence that this novel gene order could be explained by the tandem duplication/random loss (TDRL) model. The tRNA duplication/anticodon mutation mechanism further explains the presence of trnI2, which is remolded from a duplicated trnM in the TDRL process (through an anticodon mutation of CAT to GAT). Our study also raises new questions as to whether the two events proceed simultaneously and if the remolded tRNA gene is fully functional. Significantly, the duplicated tRNA gene in the mitochondrial genome has evolved independently at least two times within assassin bugs.

In this paper, we construct a new two-grid algorithm of the finite element method for the Schrödinger equation in backward Euler and Crank–Nicolson fully discrete schemes. On the coarser grid, we solve coupled real and imaginary parts of the Schrödinger equation. On the fine grid, real and imaginary parts of the Schrödinger equation are decoupled, and we solve the elliptic equation about real and imaginary parts, respectively. Then, we obtain error estimates of the exact solution with the two-grid solution in the H1-norm and carry out two numerical experiments.

Rhizobia in legume root nodules fix nitrogen in symbiosomes, organelle-like structures in which a membrane from the host plant surrounds the symbiotic bacteria. However, the components that transport plant-synthesized lipids to the symbiosome membrane remain unknown. This study identified and functionally characterized the Chinese milk vetch (Astragalus sinicus) lipid transfer protein AsE246, which is specifically expressed in nodules. It was found that AsE246 can bind lipids in vitro. More importantly, AsE246 can bind the plant-synthesized membrane lipid digalactosyldiacylglycerol in vivo. Immunofluorescence and immunoelectron microscopy showed that AsE246 and digalactosyldiacylglycerol localize in the symbiosome membrane and are present in infection threads. Overexpression of AsE246 resulted in increased nodule numbers; knockdown of AsE246 resulted in reduced nodule numbers, decreased lipids contents in nodules, diminished nitrogen fixation activity, and abnormal development of symbiosomes. AsE246 knockdown also resulted in fewer infection threads, nodule primordia, and nodules, while AsE246 overexpression resulted in more infection threads and nodule primordia, suggesting that AsE246 affects nodule organogenesis associated with infection thread formation. Taken together, these results indicate that AsE246 contributes to lipids transport to the symbiosome membrane, and this transport is required for effective legume-rhizobium symbiosis.