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The emergence of 4D printing has become a pivotal tool to produce complex structures in biomedical applications such as tissue engineering and regenerative medicine. This chapter provides a concise overview of the current state of the field and its immense potential to better understand the involved technologies to build sophisticated 4D-printed structures. These structures have the capability to sense and respond to a diverse range of stimuli, which include changes in temperature, humidity, or electricity/magnetics. First, we describe 4D printing technologies, which include extrusion-based inkjet printing, and light-based and droplet-based methods including selective laser sintering (SLS). Several types of biomaterials for 4D printing, which can undergo structural changes in various external stimuli over time were also presented. These structures hold the promise of revolutionizing fields that require adaptable and intelligent materials. Moreover, biomedical applications of 4D-printed smart structures were highlighted, spanning a wide spectrum of intended applications from drug delivery to regenerative medicine. Finally, we address a number of challenges associated with current technologies, touching upon ethical and regulatory aspects of the technologies, along with the need for standardized protocols in both in vitro as well as in vivo testing of 4D-printed structures, which are crucial steps toward eventual clinical realization.

The recent developments in the replacement of bulk MOSFETs with high-performance semiconductor devices create new opportunities in attaining the best device configuration with drive current, leakage current, subthreshold swing, Drain-Induced Barrier Lowering (DIBL), and other short-channel effect (SCE) parameters. Now, multigate FETs (FinFET and tri-gate (TG)) are advanced methodologies to continue the scaling of devices. Also, strain technology is used to gain a higher current drive, which raises the device performance, and high-k dielectric material is used to minimize the subthreshold current. In this work, we used stacked high-k dielectric materials in a TG n-FinFET with three fins and a 10 nm channel length, incorporating a three-layered strained silicon channel to determine the short-channel effects. Here, we replaced the gate oxide (SiO 2 ) with a stacked gate oxide of 0.5 nm of SiO 2 with a 0.5 nm effective oxide thickness of different high-k dielectric materials like Si 3 N 4 , Al 2 O 3 , ZrO 2, and HfO 2 . It was found that the use of strained silicon and replacing only the SiO 2 device with the stacked SiO 2 and HfO 2 device was more beneficial to obtain an optimized device with the least leakage and improved drive currents.

Intra-articular injections are widely used for diagnostic and therapeutic purposes of joint pathologies throughout the body. These injections can be performed blind by utilizing anatomical landmarks or with the use of imaging modalities to directly visualize the joint space during injections. This review of the literature aims to comprehensively identify differences in the accuracy of intra-articular injections via palpation vs. image guidance in the most commonly injected joints in the upper and lower extremities. To our knowledge, there are no such comprehensive reviews available. A narrative literature review was performed using PubMed and Google Scholar databases to identify studies focusing on the accuracy of blind or image-guided intra-articular injections for each joint. A total of 75 articles was included in this review, with blind and image-guided strategies being discussed for the most commonly injected joints of the upper and lower extremities. Varying ranges of accuracy with blind and image-guided modalities were found throughout the literature, though an improvement in accuracy was seen in nearly all joints when using image guidance. Differences are pronounced, particularly in deep joints such as the hip or in the small joints such as those in the hand or foot. Image guidance is a useful adjunct for most intra-articular injections, if available. Though there is an increase in accuracy in nearly all joints, minor differences in accuracy seen in large, easily accessed joints, such as the knee, may not warrant image guidance.

Porous structured metallic implants are preferable as bone graft substitutes due to their faster tissue integration mediated by bone in-growth and vascularization. The porous scaffolds/implants should also mimic the graded structure of natural bone to ensure a match of mechanical properties. This article presents a method for designing a graded porous structured acetabular implant and identifies suitable parameters for manufacturing the model through additive manufacturing. The design method is based on slice-wise modification to ensure continuity of gradation. Modification of the slices was achieved through the binary image processing route. A geodesic dome-type design was adopted for developing the acetabular cup model from the graded porous structure. The model had a solid shell with the target porosity and pore size gradually changing from 65% and 950 µm, respectively, in the inner side to 75% and 650 µm, respectively, towards the periphery. The required dimensions of the unit structures and the combinations of pore structure and strut diameter necessary to obtain the target porosity and pore size were determined analytically. Suitable process parameters were identified to manufacture the model by Direct Metal Laser Sintering (DMLS) using Ti6Al4V powder after carrying out a detailed experimental study to minimize the variation of surface roughness and warping over different build angles of the strut structures. Dual-contour scanning was implemented to simplify the scan strategy. The minimum diameter of struts that could be manufactured using the selected scanning strategy and scanning parameters was found to be 375 µm. Finally, the model was built and from the micro-CT data, the porosities and pore sizes were found to be closely conforming to the designed values. The stiffness of the structures, as found from compression testing, was also found to match with that of human trabecular bone well. Further, the structure exhibited compliant bending-dominated behaviour under compressive loading.

The application of Trichoderma is a form of biological control that has been effective in combating Xanthomonas oryzae pv. oryzae , the causative agent of the devastating disease known as bacterial blight of rice. In this present study, four strains of Trichoderma, viz., T. paraviridescens (BDISOF67) , T. erinaceum (BDISOF91), T. asperellum (BDISOF08), and T. asperellum (BDISOF09), were collected from the rice rhizosphere and used to test their potentiality in reducing bacterial blight. The expression patterns of several core defense-related enzymes and genes related to SA and JA pathways were studied to explore the mechanism of induced resistance by those Trichoderma strains. The results primarily indicated that all Trichoderma were significantly efficient in reducing the lesion length of the leaf over rice check variety (IR24) through enhancing the expression of core defense-related enzymes, such as PAL, PPO, CAT, and POD activities by 4.27, 1.77, 3.53, and 1.57-fold, respectively, over control. Moreover, the results of qRT-PCR exhibited an upregulation of genes OsPR1 , OsPR10 , OsWRKY45 , OsWRKY62 , OsWRKY71 , OsHI-LOX , and OsACS2 after 24 h of inoculation with all tested Trichoderma strains. However, in the case of RT-PCR, no major changes in OsPR1 and OsPR10 expression were observed in plants treated with different Trichoderma strains during different courses of time. Collectively, Trichoderma induced resistance in rice against X. oryzae pv. oryzae by triggering these core defense-related enzymes and genes associated with SA and JA pathways.

Gut microbes and their metabolites are actively involved in the development and regulation of host immunity, which can influence disease susceptibility. Herein, we review the most recent research advancements in the gut microbiota-immune axis. We discuss in detail how the gut microbiota is a tipping point for neonatal immune development as indicated by newly uncovered phenomenon, such as maternal imprinting, in utero intestinal metabolome, and weaning reaction. We describe how the gut microbiota shapes both innate and adaptive immunity with emphasis on the metabolites short-chain fatty acids and secondary bile acids. We also comprehensively delineate how disruption in the microbiota-immune axis results in immune-mediated diseases, such as gastrointestinal infections, inflammatory bowel diseases, cardiometabolic disorders (e.g., cardiovascular diseases, diabetes, and hypertension), autoimmunity (e.g., rheumatoid arthritis), hypersensitivity (e.g., asthma and allergies), psychological disorders (e.g., anxiety), and cancer (e.g., colorectal and hepatic). We further encompass the role of fecal microbiota transplantation, probiotics, prebiotics, and dietary polyphenols in reshaping the gut microbiota and their therapeutic potential. Continuing, we examine how the gut microbiota modulates immune therapies, including immune checkpoint inhibitors, JAK inhibitors, and anti-TNF therapies. We lastly mention the current challenges in metagenomics, germ-free models, and microbiota recapitulation to a achieve fundamental understanding for how gut microbiota regulates immunity. Altogether, this review proposes improving immunotherapy efficacy from the perspective of microbiome-targeted interventions.

Magnetic hyperthermia (MH), proposed by R. K. Gilchrist in the middle of the last century as local hyperthermia, has nowadays become a recognized method for minimally invasive treatment of oncological diseases in combination with chemotherapy (ChT) and radiotherapy (RT). One type of MH is arterial embolization hyperthermia (AEH), intended for the presurgical treatment of primary inoperable and metastasized solid tumors of parenchymal organs. This method is based on hyperthermia after transcatheter arterial embolization of the tumor's vascular system with a mixture of magnetic particles and embolic agents. An important advantage of AEH lies in the double effect of embolotherapy, which blocks blood flow in the tumor, and MH, which eradicates cancer cells. Consequently, only the tumor undergoes thermal destruction. This review introduces the progress in the development of polymeric magnetic materials for application in AEH.

Herein, a three-dimensional (3D) Fe 3 O 4 @C composite with hollow porous structure is prepared by simple solution method and calcination treatment with biomass waste rape pollen (RP) as a carbon source, which is served as an anode of Li-ion capacitor (LIC). The 3D interconnected porous structure and conductive networks facilitate the transfer of ion/electron and accommodate the volume changes of Fe 3 O 4 during the electrochemical reaction process, which leads to the excellent performance of the Fe 3 O 4 @C composite electrode. The electrochemical analysis demonstrates that the hybrid LIC fabricated with Fe 3 O 4 @C as the anode and activated carbon (AC) as the cathode can operate at a voltage of 4.0 V and exhibit a high energy density of 140.6 Wh kg -1 at 200 W kg -1 (52.8 Wh kg -1 at 10 kW kg -1 ), along with excellent cycling stability, with a capacity retention of 83.3% over 6000 cycles. Hence, these encouraging results indicate that Fe 3 O 4 @C has great potential in developing advanced LICs electrode materials for the next generation of energy storage systems.

Extracellular nano vesicles and exosomes hold compelling evidence in intercellular communication. Exosomal intracellular signal transduction is mediated by the transfer of cargo proteins, lipids, micro (mi)RNAs, long noncoding (lnc)RNAs, small interfering (si)RNAs, DNA, and other functional molecules that play a pivotal role in regulating tumor growth and metastasis. However, emerging research trends indicate that exosomes may be used as a promising tool in anticancer treatment. This review features a majority of the bioengineering applications of fabricated exosomal cargoes. It also encompasses how the manipulation and delivery of specific cargoes-noncoding RNAs (ncRNAs), recombinant proteins, immune-modulators, chemotherapeutic drugs, and other small molecules-may serve as a precise therapeutic approach in cancer management.

Mucosal surfaces in the gastrointestinal tract are continually exposed to native, commensal antigens and susceptible to foreign, infectious antigens. Immunoglobulin A (IgA) provides dual humoral responses that create a symbiotic environment for the resident gut microbiota and prevent the invasion of enteric pathogens. This review features recent immunological and microbial studies that elucidate the underlying IgA and microbiota-dependent mechanisms for mutualism at physiological conditions. IgA derailment and concurrent microbiota instability in pathological diseases are also discussed in detail. Highlights of this review underscore that the source of IgA and its structural form can dictate microbiota reactivity to sustain a diverse niche where both host and bacteria benefit. Other important studies emphasize IgA insufficiency can result in the bloom of opportunistic pathogens that encroach the intestinal epithelia and disseminate into circulation. The continual growth of knowledge in these subjects can lead to the development of therapeutics targeting IgA and/or the microbiota to treat life threatening diseases.

A green synthesis of silver nanoparticles (AgNPs) was conducted using the stem extract of Piper chaba , which is a plant abundantly growing in South and Southeast Asia. The synthesis was carried out at different reaction conditions, i.e., reaction temperature, concentrations of the extract and silver nitrate, reaction time, and pH. The synthesized AgNPs were characterized by visual observation, ultraviolet-visible (UV-vis) spectroscopy, dynamic light scattering (DLS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), x-ray diffraction (XRD), energy dispersive x-ray (EDX), and Fourier transform infrared (FTIR) spectroscopy. The characterization results revealed that AgNPs were uniformly dispersed and exhibited a moderate size distribution. They were mostly spherical crystals with face-centered cubic structures and an average size of 19 nm. The FTIR spectroscopy and DLS analysis indicated that the phytochemicals capping the surface of AgNPs stabilize the dispersion through anionic repulsion. The synthesized AgNPs effectively catalyzed the reduction of 4-nitrophenol (4-NP) and degradation of methylene blue (MB) in the presence of sodium borohydride.

To improve Li storage capacity and the structural stability of Ti 3 C 2 MXene-based electrode materials for lithium-ion batteries (LIBs), a facile strategy is developed to construct three-dimensional (3D) hierarchical porous Ti 3 C 2 /bimetal-organic framework (NiCo-MOF) nanoarchitectures as anodes for high-performance LIBs. 2D Ti 3 C 2 nanosheets are coupled with NiCo-MOF nanoflakes induced by hydrogen bonds to form 3D Ti 3 C 2 /NiCo-MOF composite films through vacuum-assisted filtration technology. The morphology and electrochemical properties of Ti 3 C 2 /NiCo-MOF are influenced by the mass ratio of MOF to Ti 3 C 2 . Owing to the interconnected porous structures with a high specific surface area, rapid charge transfer process, and Li + diffusion rate, the Ti 3 C 2 /NiCo-MOF-0.4 electrode delivers a high reversible capacity of 402 mAh g -1 at 0.1 A g -1 after 300 cycles; excellent rate performance (256 mAh g -1 at 1 A g -1 ); and long-term stability with a capacity retention of 85.7% even after 400 cycles at a high current density, much higher than pristine Ti 3 C 2 MXene. The results highlight that Ti 3 C 2 /NiCo-MOF have great potential in the development of high-performance energy storage devices.

In this work, a facile two-step strategy is adopted to construct hierarchical polyaniline/NiCo-layered double hydroxide (PANI/NiCo-LDH) core-shell composite nanofiber networks on carbon cloth (CC). Three-dimensional (3D) porous PANI nanofiber networks are firstly uniformly anchored on CC by in-situ oxidative polymerization, followed by growth of NiCo-LDH nanoflakes on the crosslinked PANI framework via electrochemical deposition. The morphology and electrochemical properties of PANI/NiCo-LDH composites are controlled by the deposition time of LDH. Benefiting from rapid electron transport and ion diffusion, the well-defined PANI/NiCo-LDH hierarchical composite with 200 s deposition of LDH delivers a large capacitance of 1845 F g -1 at 0.5 A g -1 and excellent cycling stability of 82% capacitance retention after 5000 cycles at a very high current density of 10.0 A g -1 . Furthermore, an asymmetric supercapacitor (ASC) assembled with PANI/NiCo-LDH as a positive electrode and activated carbon (AC) as a negative electrode exhibits a high capacitance of 147.2 F g -1 in a potential range from 0 to 1.5 V and superior energy density of 46.0 Wh kg -1 at a power density of 351.6 W kg -1 .

Air pollution has become an emerging invisible killer in recent years and is a major cause of morbidity and mortality globally. More than 90% of the world's children breathe toxic air every day. India is among the top ten most highly polluted countries with an average PM 10 level of 134 μg/m³ per year. It is reported that 99% of India's population encounters air pollution levels that exceed the World Health Organization Air Quality Guideline, advising a PM 2.5 permissible level of 10 μg/m³. Maternal exposure to air pollution has serious health outcomes in offspring because it can affect embryonic phases of development during the gestation period. A fetus is more prone to effects from air pollution during embryonic developmental phases due to resulting oxidative stress as antioxidant mechanisms are lacking at that stage. Any injury during this vulnerable period (embryonic phase) will have a long-term impact on offspring health, both early and later in life. Epidemiological studies have revealed that maternal exposure to air pollution increases the risk of development of airway disease in the offspring due to impaired lung development in utero. In this review, we discuss cellular mechanisms involved in maternal exposure to air pollution and how it can impact airway disease development in offspring. A better understanding of these mechanisms in the context of maternal exposure to air pollution can offer a new avenue to prevent the development of airway disease in offspring.

Hierarchical copper oxide @ ternary nickel cobalt sulfide (CuO/Cu₂O@NiCo₂S₄) core-shell nanowire arrays on Cu foam have been successfully constructed by a facile two-step strategy. Vertically aligned CuO/Cu₂O nanowire arrays are firstly grown on Cu foam by one-step thermal oxidation of Cu foam, followed by electrodeposition of NiCo₂S₄ nanosheets on the surface of CuO/Cu₂O nanowires to form the CuO/Cu₂O@NiCo₂S₄ core-shell nanostructures. Structural and morphological characterizations indicate that the average thickness of the NiCo₂S₄ nanosheets is ~20 nm and the diameter of CuO/Cu₂O core is ~50 nm. Electrochemical properties of the hierarchical composites as integrated binder-free electrodes for supercapacitor were evaluated by various electrochemical methods. The hierarchical composite electrodes could achieve ultrahigh specific capacitance of 3.186 F cm -2 at 10 mA cm -2 , good rate capability (82.06% capacitance retention at the current density from 2 to 50 mA cm -2 ) and excellent cycling stability, with capacitance retention of 96.73% after 2000 cycles at 10 mA cm -2 . These results demonstrate the significance of optimized design and fabrication of electrode materials with more sufficient electrolyte-electrode interface, robust structural integrity and fast ion/electron transfer., Competing Interests: The authors declare no conflict of interest.

Extensins are members of the cell wall hydroxyproline-rich glycoprotein (HRGP) superfamily that form covalently cross-linked networks in primary cell walls. A knockout mutation in EXT3 (AT1G21310), the gene coding EXTENSIN 3 (EXT3) in Arabidopsis Landsberg erecta resulted in a lethal phenotype, although about 20% of the knockout plants have an apparently normal phenotype (ANP). In this study the root cell wall HRGP components of wild-type, ANP and the ext3 mutant seedlings were characterized by peptide fractionation of trypsin digested anhydrous hydrogen fluoride deglycosylated wall residues and by sequencing using LC-MS/MS. Several HRGPs, including EXT3, were identified in the wild-type root walls but not in walls of the ANP and lethal mutant. Indeed the ANP walls and walls of mutants displaying the lethal phenotype possessed HRGPs, but the profiles suggest that changes in the amount and perhaps type may account for the corresponding phenotypes.