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In this study, we present a straightforward and environmentally friendly electrochemical approach for achieving selective halogenation of N‐heteroarenes, including indoles, diazoles, pyrroles, quinolinone, and naphthols. Our method utilizes commercially available and affordable ammonium halides as halogen source. A library of valuable halogenated N‐heteroarenes can be synthesized in moderate to excellent yields under mild conditions (transition‐metal‐free, oxidant‐free, ethanol as solvent, atmospheric environment). The approach demonstrates a broad substrate scope, excellent tolerance towards various functional groups, and scalability. [ABSTRACT FROM AUTHOR]

Context: The potential anti-inflammatory bioactivities of b-hydroxyisovalerylshikonin (b-HIVS) remain largely unknown. Objective: This study investigated the anti-inflammatory effects and underlying mechanisms of b-HIVS. Materials and methods: RAW 264.7 cells stimulated with LPS (100 ng/mL) for 24 h were treated with the non-cytotoxic doses of b-HIVS (0.5 or 1 lM, determined by MTT and Trypan blue staining), qRT-PCR and FCM assay were used to examine macrophage polarization transitions. Western blotting was used to evaluate the activation of the AMPK/Nrf2 pathway. In vivo, C57BL/6 mice were randomly divided into vehicle control, LPS (10mg/kg), and b-HIVS (2.5 mg/kg) combined with LPS (10 mg/kg) groups, blood samples, BALF, and lung tissues of mice were subjected to ELISA, qRT-PCR, FCM, and H&E staining. Results: b-HIVS (1 lM) inhibited LPS-induced expression of M1 macrophage markers (TNF-a: 0.29-fold, IL-1b: 0.32-fold), promoted the expression of M2 macrophage markers (CD206: 3.14-fold, Arginase-1: 3.98-fold) in RAW 264.7 cells; mechanistic studies showed that b-HIVS increased the expression of nuclear Nrf2 (2.04-fold) and p-AMPK (3.65-fold) compared with LPS group (p<0.05). In vivo, b-HIVS decreased the levels of pro-inflammatory cytokines (TNF-a: 1130.41 vs. 334.88 pg/mL, IL-1b: 601.89 vs. 258.21 pg/mL in serum; TNF-a: 893.07 vs. 418.21 pg/mL, IL-1b: 475.22 vs. 298.54 pg/mL in BALF), decreased the proportion of M1 macrophages (77.83 vs. 68.53%) and increased the proportion of M2 macrophages (13.55 vs. 19.56%) in BALF, and reduced lung tissue damage and septic mice survival (p<0.05). Conclusions: These results indicate that b-HIVS may be a new potential anti-inflammatory agent. [ABSTRACT FROM AUTHOR]

Rapid urbanizations impose increasing challenges on safety decompositions of those buildings that reached service life, so there is an urgent call for eco-friendly demolition methods. As a green demolition method, the technique of soundless cracking demolition agents (SCDAs) can effectively eliminate dust and noise pollution commonly encountered in conventional methods, and thus attract rising attention in light of increasing concerns for sustainable and low-carbon developments. Herein, this paper provides a state-of-art review of SCDAs and associated applications. SCDA, a powdery material, mainly consists of quicklime (CaO), which tends to expand significantly when mixed with water. The expansion properties of SCDAs are susceptible to internal and external factors, such as compositions, ambient temperature, mixing water temperature, and water/cement (W/C) ratio, restraint conditions, among others. Therefore, substantial efforts have been made to improve the expansion performance of SCDAs by regulating the abovementioned factors. The resulting expansion force from SCDA expansion can effectively crack brittle materials, e.g., concrete and rocks, the cracking process of which can be measured using strain gauges and Acoustic Emission (AE). More recently, digital image correlation and computed tomography have been employed to monitor the SCDA-induced cracking process, and the implementation of those new techniques promotes the observations of crack developments and underlying mechanisms. To gain a cost-effective application of SCDAs, extensive efforts have been undertaken to optimize the design in hole parameters. Accordingly, several empirical equations have been proposed for determinations of optimal hole parameters, but the application of the equations is restricted to particular conditions where they are proposed. Despite the successful usage of the SCDA technique in demolitions of construction structures, mining, unconventional gas and oil recovery, some limitations, namely hard rock fragmentation, precise numerical works and blowout, still need to be addressed for further applications. Overall, this paper gives a brief review of SCDAs, covering scopes of compositions, expansion properties, applications, inadequacies and prospects, deepening our understanding of SCDAs, and providing recommendations for future research priorities. • Factors influencing the expansion characteristics of SCDAs are analyzed. • Some new technologies for observing the process of crack development are presented. • The optimum usage of SCDA related to the hole design parameters is summarized. • Further work in the research and application of SCDA is proposed. [ABSTRACT FROM AUTHOR]

• The optimum usage of SCDA in fragmentating SFRC is comprehensively investigated. • The cracking process is commonly controlled by hole parameters and SFRC properties. • Effectivecracked area is proposed to assess the cracking performance of SCDA. • An equation is formulated to quantitatively evaluate the fragmentation ability. A better application of Soundless Chemical Demolition Agents (SCDAs) in fragmentation is based on our knowledge on their expansive characteristics. In this study, an integration of experimental and modeling approaches was developed to investigate SCDA expansion and corresponding cracking processes of Steel Fiber Reinforced Concrete (SFRC). The expansive properties of the selected SCDA were first estimated by free volume expansion (FVE) tests and expansion pressure (EP) tests. Then, cracking experiments were performed on 150 mm cubic SFRC blocks with a predrilled hole, and the cracking process was monitored by using Acoustic Emission (AE) and Digital Image Correlation (DIC) techniques. Generally, the cracking process can be divided into three phases, termed micro-cracking phase, macro-cracking phase, and failure phase. It was observed the hole diameter and fiber content exert significant influences on the cracking process. The crack initiation time was shortened as the hole diameter increases, while it was prolonged with increasing fiber content. The cracked area ratio was further proposed and measured to assess the cracking performance of SCDA. The ratio increases from 2.73% to 8.293% as the hole diameter increases from 16 mm to 26 mm, while it decays from 9.75% to 1.823% as the fiber content increases from 0 to 2.4%. After verified with the experimental data, a modified Concrete Damaged Plasticity (CDP) model was adopted to extend the fragmentation of SFRC from the centimeter scale to the meter scale. The simulations were conducted on SFRC models with various hole diameters, spacings, and fiber contents. The simulated results show the fragmentation performance is related to both hole parameters (e.g., hole diameter, spacing, etc.) and SFRC properties (including elastic modulus, fiber content, etc.). In particular, the cracked area (DamageT > 0.9) varies directly with hole spacing, diameter, and fiber content. Built on the simulated results, an empirical equation was formulated to quantitatively evaluate the fragmentation ability of individual holes. In addition, extra simulations were conducted to assess the efficiency of SCDA in cracking PC/SFRC beams of various sizes. The obtained cracked area tends to decrease first and then approach a constant value with increasing beam sizes, indicating the existence of a size effect, which is primarily due to variations in concrete restraints provided by beams of different sizes. This work quantitatively evaluates expansive properties of SCDA and SCDA-induced cracks, and thus provides a reference for optimizing the field application parameters. [ABSTRACT FROM AUTHOR]

Inflammation is an innate immune response of the body against pathogens and other irritants. The NLRP3 (NACHT, LRR and PYD domains-containing protein 3) inflammasome is a major player in the inflammatory response against pathogenic microorganisms. In this study, we analyzed the relationship between the NLRP3 inflammasome and the influenza virus NS1 protein, which is involved in host immune escape. The canine influenza virus NS1 protein transcriptionally attenuated proinflammatory cytokines by inhibiting the nuclear factor-κB (NF-κB) activator. NS1 also directly interacted with NLRP3 and blocked ASC (Apoptosis-associated speck-like protein containing CARD) oligomerization, which deactivated the NLRP3 inflammasome. In addition, NS1 inhibited pro-caspase 1 cleavage into caspase-1, which prevents maturation of IL-1β and IL-18 from their respective precursors, eventually reducing the inflammatory response. Taken together, the influenza NS1 protein evades host immunity, and our findings provide a theoretical basis for the prevention and treatment of canine influenza. [ABSTRACT FROM AUTHOR]

A highly sensitive mid-infrared evanescent wave sensor based on side-polished (SPF) chalcogenide fiber (ChG) was proposed in this work. The optimum optical fiber parameters were determined via numerical simulation by detecting the leakage intensity of evanescent waves from the optical fiber of different polish depths. The SPF remarkably enhanced the evanescent wave sensing while maintaining fiber loss and strength. Graphene oxide (GO) was coated on the fiber to enhance the sensitivity of SPF sensor for butane (C 4 H 10). GO has a great specific surface area and abundant oxygen-containing functional groups, which enlarges the contact area of GO with gas molecules and enables to adsorb gas. Results show that the GO-SPF sensor can be three and five times more sensitive than the original fiber optic sensor and SPF sensor for butane gas detection, and has a fast response time and good repeatability. [ABSTRACT FROM AUTHOR]

Evaluating actual crop evapotranspiration (ETc) variations and their determining factors under changing climates is crucial for agricultural irrigation management and crop productivity improvement in nonhumid regions. This study analyzed the spatiotemporal characteristics and detected the determining factors of ETc for winter wheat and summer maize rotation system from 2000 to 2017 in the North China Plain (NCP), by combining the FAO-56 dual crop coefficient approach with remotely sensed vegetation indices (VIs). The results indicated that daily air temperature increased in varying degrees while wind speed and sunshine hours decreased slightly during the growing season of winter wheat and summer maize over the study period. The trends of relative humidity and effective precipitation varied in crop growing seasons. Based on the validated relationship of dual crop coefficients and VIs, the estimated multi-year average ETc of winter wheat (370.29 ± 31.28 mm) was much higher than summer maize (281.85 ± 20.14 mm), and the rotation cycle was 652.43 ± 27.67 mm. Annual ETc of winter wheat and the rotation cycle increased by 2.96 mm a-1 and 1.77 mm a-1, respectively. However, the ETc of summer maize decreased with distinct spatial variation. Spatially, winter wheat ETc increased significantly in the northeast NCP, covering the Beijing-Tianjin-Hebei areas. Meanwhile, significant increases in summer maize ETc were detected in the southwest NCP. The sensitivity and contribution analysis showed that ETc of winter wheat and summer maize was positively sensitive to temperature, wind speed, and sunshine hours while negatively to relative humidity. Moreover, wind speed and sunshine hours contributed most to changes in ETc (around 20%-40%). [ABSTRACT FROM AUTHOR]

The early detection of esophageal cancer is crucial for enhancing patient survival. Surface-enhanced Raman scattering (SERS), renowned for its precise detection capabilities of low-concentration molecules and organisms, holds immense promise for early diagnosis. However, the use of silver nanoparticles to enhance the Raman signal can disrupt the detection process. To address this problem in this study, we synthesized polyethylene glycol (PEG)-coated silver nanocubes (PEG-AgNCs) as stable, label-free, and low-toxicity nanoprobes for detecting esophageal cancer. AgNCs with sharp corners and edges are selected as the SERS substrate to increase the strength of the Raman signal. To minimize the toxicity of AgNCs, the surface is coated with PEG, which exhibits outstanding biocompatibility. The SERS effectiveness of PEG-AgNCs was evaluated using 4-mercaptobenzoic acid as a Raman probe molecule, and the toxicity of PEG-AgNCs at different concentrations was investigated using human keratinocytes (HaCaT) and human esophageal carcinoma cells (TE-1). Results showed that PEG-AgNCs can effectively reduce the toxicity of AgNCs while maintaining a strong SERS signal. Remarkable differences in Raman spectra were observed between HaCat and TE-1 cells within the spectral range of 588–768 cm−1, indicating the potential of PEG-AgNCs in the early detection of esophageal cancer using Raman detection. Our study highlights the potential of developing low-toxicity SERS biosensors for biological and chemical analyses. • The toxicity of AgNCs to living organisms was systematically investigated by two different methods. • PEG-AgNCs was can effectively reduce the toxicity of AgNCs while maintaining a strong SERS signal. • The prepared PEG-AgNCs have great potentialfor early esophageal cancer detection. [ABSTRACT FROM AUTHOR]

Esophageal foreign body impaction is a notable clinical emergency. If the high-risk esophageal foreign bodies are not removed in time, life-threatening complications, such as perforation, infection and injury to the vessels, may occur. In the present study, the case of a patient experiencing a foreign body sensation in the throat after ingesting a fish bone by mistake is presented. A high risk of impending arterial puncture was confirmed using thoracic CT and thoracic aorta CT angiography scanning. The ends of the fish bone were first confirmed using a fibro-bronchoscopy light source passing through the bronchial and esophageal walls, before biopsy forceps were used to successively free the thoracic aorta and bronchial ends under gastroscopy. Finally, the fish bone was safely removed using a combination of gastroscopy and the rarely used fibro-bronchoscopy, and the patient recovered well after standard care. In certain cases of foreign bodies, it is necessary to use multiple strategies in a timely manner according to the type and location of the ingested foreign body. [ABSTRACT FROM AUTHOR]

Objectives The genus Streptococcus contains species of important zoonotic pathogens such as those that cause bovine mastitis. Unfortunately, many Streptococcus species have developed antibiotic resistance. Phage lysins are considered promising alternatives to antibiotics because it is difficult for bacteria to develop lysin resistance. However, there remains a lack of phage lysin resources for the treatment of streptococci-induced mastitis. Methods We identified the prophage lysin Lys0859 from the genome of the Streptococcus suis SS0859 strain. Lys0859 was subsequently characterized to determine its host range, MIC, bactericidal activity in milk, and ability to clear biofilms in vitro. Finally, to determine the effects of Lys0859 on the treatment of both bovine mastitis and S. suis infection in vivo , we established models of Streptococcus agalactiae ATCC 13813-induced mastitis and S. suis serotype 2 SC19 systemic infection. Results Our results demonstrate that Lys0859 possesses broad-spectrum lytic activity against Streptococcus and Staphylococcus species isolated from animals with bovine mastitis and 15 serotypes of S. suis isolated from swine. Intramammary and intramuscular injection of Lys0859 reduced the number of bacteria in mammary tissue by 3.75 and 1.45 logs compared with the PBS group, respectively. Furthermore, 100 μg/mouse of Lys0859 administered intraperitoneally at 1 h post-infection protected 83.3% (5/6) of mice from a lethal dose of S. suis infection. Conclusions Overall, our results enhance the understanding and development of new strategies to combat both streptococci-induced mastitis and S. suis infection. [ABSTRACT FROM AUTHOR]

Although the synthesis of α‐tertiary amino acids (ATAAs) has been extensively studied, the development of an inexpensive and facile methodology to incorporate multifunctionality on ATAAs remains challenging. In this article, we present a single‐step radical approach for the modular synthesis of functionally diverse ATAAs. This synthesis takes place under mild conditions with an absence of metals, photocatalysts, and all other additives. We demonstrate the broad applications of this approach on a variety of aliphatic and aromatic carboxylic acids, alkenes, 1,3‐enynes, and oxazolones. The results prove that our method provides excellent functional group tolerance and late‐stage applicability, as well as gram‐scale synthesis via flow chemistry. Additionally, we include mechanistic studies which reveal that the excited state of oxazolone enolate upon light excitation is a key intermediate that acts as a radical precursor and an efficient reductant. [ABSTRACT FROM AUTHOR]

Although the synthesis of α‐tertiary amino acids (ATAAs) has been extensively studied, the development of an inexpensive and facile methodology to incorporate multifunctionality on ATAAs remains challenging. In this article, we present a single‐step radical approach for the modular synthesis of functionally diverse ATAAs. This synthesis takes place under mild conditions with an absence of metals, photocatalysts, and all other additives. We demonstrate the broad applications of this approach on a variety of aliphatic and aromatic carboxylic acids, alkenes, 1,3‐enynes, and oxazolones. The results prove that our method provides excellent functional group tolerance and late‐stage applicability, as well as gram‐scale synthesis via flow chemistry. Additionally, we include mechanistic studies which reveal that the excited state of oxazolone enolate upon light excitation is a key intermediate that acts as a radical precursor and an efficient reductant. [ABSTRACT FROM AUTHOR]

• We use centrifuge experiments and large deformation finite element simulations to investigate the capacity of vertically loaded spudcan foundations under sustained uplift. • The sustained threshold load of spudcans ranges from about 50 % to 70 % of their monotonic capacity. • The monotonic capacity after vertical sustained loading is investigated. • A step-by-step guide is provided to estimate the sustained capacity of spudcans for various operational durations. Spudcan extraction has long been a challenging issue in engineering, necessitating a thorough understanding of spudcan sustained capacity. Prior studies have predominantly focused on the monotonic capacity of spudcans, which is distinct from the engineering practice of sustained loading. This paper studies the capacity of spudcans deeply embedded in normally consolidated clay during and after vertical sustained loading through centrifuge tests and numerical simulations. The sustained threshold load of spudcans ranges from approximately 50 % to 70 % of their monotonic capacity, and it gradually decreases with increasing operation period. When the applied load exceeds the threshold load, the uplift displacement of the spudcan exhibits creep characteristics characterised by an initial rapid rate, followed by consistent growth and ultimately accelerated failure. The greater the sustained load is, the sooner the spudcan fails. When the sustained load is far lower than the threshold load, the undrained spudcan capacity after sustained loading closely aligns with the monotonic undrained capacity under long-term operation consolidation. However, this capacity diminishes considerably at sustained forces near the threshold load. A step-by-step guide is also included to estimate the sustained threshold load for various operational durations. [ABSTRACT FROM AUTHOR]

Recent epidemiological studies have discovered that a lot of cases of porcine epidemic diarrhea virus (PEDV) infection are frequently accompanied by porcine kobuvirus (PKV) infection, suggesting a potential relationship between the two viruses in the development of diarrhea. To investigate the impact of PKV on PEDV pathogenicity and the number of intestinal lymphocytes, piglets were infected with PKV or PEDV or co-infected with both viruses. Our findings demonstrate that co-infected piglets exhibit more severe symptoms, acute gastroenteritis, and higher PEDV replication compared to those infected with PEDV alone. Notably, PKV alone does not cause significant intestinal damage but enhances PEDV's pathogenicity and alters the number of intestinal lymphocytes. These results underscore the complexity of viral interactions in swine diseases and highlight the need for comprehensive diagnostic and treatment strategies addressing co-infections. • Co-infection with PKV synergistically aggravates the clinical symptoms and pathological damage of PEDV-infected piglets. • PKV promotes the replication of PEDV in the epithelial cells of the small intestine of the piglets. • PKV infection reduces CD3+ T lymphocytes , CD4+ T lymphocytes , and B lymphocytes in the small intestine of the piglets. [ABSTRACT FROM AUTHOR]

Chalcogenide glasses (ChGs) excellent optical materials in the infrared range. ChG lens has important applications in the environmental detection and biochemical imaging field. In this paper, microlens arrays (MLA) with good optical quality were prepared by wet-etching assisted femtosecond laser direct writing technology and 2300 microlenses were prepared in the range of 1 mm2. By controlling the power of laser direct writing and the time of chemical etching, microlenses with diameters ranging from 15 to 70 μm could be prepared. An uniform dense stacked MLA with a small volume in the wavelength range of 0.6–12 μm was achieved. The fabricated MLA has a broad application scenario in cutting-edge mid-infrared fields, due to their tiny size, light weight, high integration, and excellent optical quality. [ABSTRACT FROM AUTHOR]

Foot-and-mouth disease virus (FMDV) is a highly contagious pathogen that has caused significant economic losses in the livestock industry. Peptide vaccines engineered with the protective epitopes of FMDV have provided a safer alternative for disease prevention than the traditional inactivated vaccines. However, the immunogenicity of the peptide is usually poor and therefore an adjuvant is required. Here, we showed that recombinant T4 phages displaying the B-cell epitope of the FMDV VP1 protein (VP1 130–158), without additional adjuvants, induced similar levels of antigen-specific IgG1 but higher levels of IgG2a compared to the peptide vaccine. Incorporation of a CD4+ T cell epitope, either 3A 21–35 of FMDV 3A protein or P2 830–844 of tetanus toxoid, further enhanced the immunogenicity of VP1-T4 phage nanoparticles. Interestingly, the extrinsic adjuvant cannot enhance the immunogenicity of the nanoparticles, indicating the intrinsic adjuvant activities of T4 phage. Furthermore, the recombinant T4 phage can be produced on a large scale within a short period of time at a relatively low-cost using Escherichia coli , heralding its potential in the development of a safe and effective FMDV vaccine. [ABSTRACT FROM AUTHOR]

Welding expulsion is a common problem in the resistance spot welding (RSW) process, which severely impacts weld quality and surrounding facilities. Existing expulsion control strategies are ineffective for complex and changeable welding conditions. This article studied the growth relationship between weld nugget and corona bond under two abnormal conditions: edge proximity (EP) and initial sheet gaps (IG). It is testified that expulsion would occur when the nugget size exceeds the corona bond size under EP and IG conditions. Reducing the welding current before the expulsion time can increase the size difference between the corona bond and the weld nugget, thereby delay and even eliminate the occurrence of expulsion. In this way, a novel online expulsion control strategy, named short-time current regulation (STCR), is proposed through the expulsion moment analysis of historical weld data. The effect of the new control strategy is verified with workpieces ranging from low carbon steel to ultra-high strength steel. Experimental results showed that STCR can effectively reduce the amount of expelled metal, decrease the indentation depth, and increase the nugget diameter. The method not only works well under one specific abnormal condition but also adapts to the transition between different welding conditions. This novel expulsion control strategy can help achieve the expulsion-free RSW process in mass production without frequent manual offline optimization of welding parameters. [ABSTRACT FROM AUTHOR]

Wheat is one of the most common and productive crops in the world, and the growth and production of wheat are sensitive to climate change. Climate change affects wheat phenology by influencing sowing/maturity dates and the duration of growing stages, and ultimately affects the grain yield. Reliable prediction of changes in wheat yield is significant for maintaining global food security. However, studies addressing the potential impact of crop phenology changes on grain yield are rarely reported, which is a big challenge. Using the CERES-Wheat model and first-order differential equation models, we quantified the impact of future climate change on wheat phenology and grain yield for two periods (P1: 2011-2040; P2: 2041-2070) under three representative concentration pathways (RCP2.6, RCP4.5, RCP8.5) in China's twomain wheat-growing areas (Northwest SpringWheat-Growing Area(NWSWA) and Huang-Huai-Hai Winter Wheat-Growing Area (HHWWA)); the baseline period was 1981-2010. Accumulated thermal time during thewhole growing period (WGP) tends to significantly increase in NWSWA and HHWWA under all RCPs and periods. This rising accumulated thermal time will reduce the time to anthesis and maturity and shorten the vegetative growing period (VGP), reproductive growing period (RGP), and theWGP. In P2, spring wheat grain yield is projected to diminish by a regional average of 2.67% for RCP2.6, 4.07% for RCP4.5, and 5.66% for RCP8.5, which is dominated by the lower accumulated solar radiation during the VGP in NWSWA. Additionally, for the winter wheat grain yield in HHWWA in P2, its grain yield reduction is projected to decline by 4.8% (RCP2.6), 7.9% (RCP4.5), and 9.8% (RCP8.5), which is caused by increasing accumulated thermal time in the VGP. These results suggest that breeding high-temperature-tolerant varieties with high calorie requirements is an adaptive strategy to mitigate the negative impact of climate change on wheat yield in the study areas. [ABSTRACT FROM AUTHOR]

Vaccines that trigger mucosal immune responses at the entry portals of pathogens are highly desired. Here, we showed that antigen-decorated nanoparticle generated through CRISPR engineering of T4 bacteriophage can serve as a universal platform for the rapid development of mucosal vaccines. Insertion of Flu viral M2e into phage T4 genome through fusion to Soc (Small Outer Capsid protein) generated a recombinant phage, and the Soc-M2e proteins self-assembled onto phage capsids to form 3M2e-T4 nanoparticles during propagation of T4 in E. coli. Intranasal administration of 3M2e-T4 nanoparticles maintains antigen persistence in the lungs, resulting in increased uptake and presentation by antigen-presenting cells. M2e-specific secretory IgA, effector (T EM), central (T CM), and tissue-resident memory CD4+ T cells (T RM) were efficiently induced in the local mucosal sites, which mediated protections against divergent influenza viruses. Our studies demonstrated the mechanisms of immune protection following 3M2e-T4 nanoparticles vaccination and provide a versatile T4 platform that can be customized to rapidly develop mucosal vaccines against future emerging epidemics. [Display omitted] • A CRISPR/Cas-engineered universal T4 phage platform for mucosal vaccine development. • Antigen-decorated T4 phage nanoparticles mediate antigen persistence in the lung. • Influenza viral M2e-T4 nanoparticles promote antigen presentation in the lung. • Intranasal delivery of M2e-T4 nanoparticles elicits robust mucosal immune responses. • A M2e-T4 mucosal vaccine confers mice full protection against divergent flu viruses. [ABSTRACT FROM AUTHOR]

• The optimal use of SCDA in fragmentating concrete blocks is systematically studied. • Hole diameter exerts a primary control on the cracking process. • The minimum hole diameter in broken concrete blocks of certain size is achieved. • The optimum hole spacing with respect to maximum cracked area is determined. • Empirical equations with hole and concrete parameters involved are proposed. For effective applications of a soundless chemical demolition agent (SCDA) in fragmenting concrete blocks, experimental and numerical investigations were conducted. Firstly, the maximum expansion pressures under varying water/SCDA ratio, water temperature, and hole diameter were determined via experimental tests. Then, cracking experiments were performed on lab-scale concrete blocks with two predrilled holes by using strain gouge and acoustic emission tool. It was observed hole diameter exerts a primary control on the cracking process. The cracking process is generally divided into three stages, named micro-cracking stage, macro-cracking stage, and failure stage. Furthermore, two-dimensional realistic failure process analysis (RFPA2D) code was applied to reproduce the failure process of laboratory concrete blocks. The verified model was employed to simulate the cracking process of meter-scale concrete specimens with multi-holes of staggered and square arrangements. Empirical equations were formulated to correlate the cracking area with the hole diameter, spacing, and tensile strengths of concrete. [ABSTRACT FROM AUTHOR]